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996ae0b0
RK		 1------------------------------------------------------------------------------
2-- --
3-- GNAT COMPILER COMPONENTS --
4-- --
5-- S E M _ R E S --
6-- --
7-- B o d y --
8-- --
67bdbf1e 9-- Copyright (C) 1992-2012, Free Software Foundation, Inc. --
996ae0b0
RK		 10-- --
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- --
b5c84c3c 13-- ware Foundation; either version 3, or (at your option) any later ver- --
996ae0b0
RK		 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 --
b5c84c3c
RD		 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. --
996ae0b0
RK		 20-- --
21-- GNAT was originally developed by the GNAT team at New York University. --
71ff80dc 22-- Extensive contributions were provided by Ada Core Technologies Inc. --
996ae0b0
RK		 23-- --
24------------------------------------------------------------------------------
25
26with Atree; use Atree;
27with Checks; use Checks;
28with Debug; use Debug;
29with Debug_A; use Debug_A;
30with Einfo; use Einfo;
31with Errout; use Errout;
32with Expander; use Expander;
758c442c 33with Exp_Disp; use Exp_Disp;
0669bebe 34with Exp_Ch6; use Exp_Ch6;
996ae0b0 35with Exp_Ch7; use Exp_Ch7;
fbf5a39b 36with Exp_Tss; use Exp_Tss;
996ae0b0 37with Exp_Util; use Exp_Util;
dae2b8ea 38with Fname; use Fname;
996ae0b0
RK		 39with Freeze; use Freeze;
40with Itypes; use Itypes;
41with Lib; use Lib;
42with Lib.Xref; use Lib.Xref;
43with Namet; use Namet;
44with Nmake; use Nmake;
45with Nlists; use Nlists;
46with Opt; use Opt;
47with Output; use Output;
48with Restrict; use Restrict;
6e937c1c 49with Rident; use Rident;
996ae0b0
RK		 50with Rtsfind; use Rtsfind;
51with Sem; use Sem;
a4100e55 52with Sem_Aux; use Sem_Aux;
996ae0b0
RK		 53with Sem_Aggr; use Sem_Aggr;
54with Sem_Attr; use Sem_Attr;
55with Sem_Cat; use Sem_Cat;
56with Sem_Ch4; use Sem_Ch4;
57with Sem_Ch6; use Sem_Ch6;
58with Sem_Ch8; use Sem_Ch8;
4b92fd3c 59with Sem_Ch13; use Sem_Ch13;
dec6faf1 60with Sem_Dim; use Sem_Dim;
996ae0b0
RK		 61with Sem_Disp; use Sem_Disp;
62with Sem_Dist; use Sem_Dist;
16212e89 63with Sem_Elim; use Sem_Elim;
996ae0b0
RK		 64with Sem_Elab; use Sem_Elab;
65with Sem_Eval; use Sem_Eval;
66with Sem_Intr; use Sem_Intr;
67with Sem_Util; use Sem_Util;
ce72a9a3 68with Targparm; use Targparm;
996ae0b0
RK		 69with Sem_Type; use Sem_Type;
70with Sem_Warn; use Sem_Warn;
71with Sinfo; use Sinfo;
f4b049db 72with Sinfo.CN; use Sinfo.CN;
fbf5a39b 73with Snames; use Snames;
996ae0b0
RK		 74with Stand; use Stand;
75with Stringt; use Stringt;
45fc7ddb 76with Style; use Style;
996ae0b0
RK		 77with Tbuild; use Tbuild;
78with Uintp; use Uintp;
79with Urealp; use Urealp;
80
81package body Sem_Res is
82
83 -----------------------
84 -- Local Subprograms --
85 -----------------------
86
87 -- Second pass (top-down) type checking and overload resolution procedures
5cc9353d
RD		 88 -- Typ is the type required by context. These procedures propagate the type
89 -- information recursively to the descendants of N. If the node is not
90 -- overloaded, its Etype is established in the first pass. If overloaded,
91 -- the Resolve routines set the correct type. For arith. operators, the
92 -- Etype is the base type of the context.
996ae0b0
RK		 93
94 -- Note that Resolve_Attribute is separated off in Sem_Attr
95
bd29d519
AC		 96 function Bad_Unordered_Enumeration_Reference
97 (N : Node_Id;
98 T : Entity_Id) return Boolean;
99 -- Node N contains a potentially dubious reference to type T, either an
100 -- explicit comparison, or an explicit range. This function returns True
101 -- if the type T is an enumeration type for which No pragma Order has been
102 -- given, and the reference N is not in the same extended source unit as
103 -- the declaration of T.
104
996ae0b0
RK		 105 procedure Check_Discriminant_Use (N : Node_Id);
106 -- Enforce the restrictions on the use of discriminants when constraining
107 -- a component of a discriminated type (record or concurrent type).
108
109 procedure Check_For_Visible_Operator (N : Node_Id; T : Entity_Id);
110 -- Given a node for an operator associated with type T, check that
111 -- the operator is visible. Operators all of whose operands are
112 -- universal must be checked for visibility during resolution
113 -- because their type is not determinable based on their operands.
114
c8ef728f
ES		 115 procedure Check_Fully_Declared_Prefix
116 (Typ : Entity_Id;
117 Pref : Node_Id);
118 -- Check that the type of the prefix of a dereference is not incomplete
119
996ae0b0
RK		 120 function Check_Infinite_Recursion (N : Node_Id) return Boolean;
121 -- Given a call node, N, which is known to occur immediately within the
122 -- subprogram being called, determines whether it is a detectable case of
123 -- an infinite recursion, and if so, outputs appropriate messages. Returns
124 -- True if an infinite recursion is detected, and False otherwise.
125
126 procedure Check_Initialization_Call (N : Entity_Id; Nam : Entity_Id);
127 -- If the type of the object being initialized uses the secondary stack
128 -- directly or indirectly, create a transient scope for the call to the
fbf5a39b
AC		 129 -- init proc. This is because we do not create transient scopes for the
130 -- initialization of individual components within the init proc itself.
996ae0b0
RK		 131 -- Could be optimized away perhaps?
132
f61580d4 133 procedure Check_No_Direct_Boolean_Operators (N : Node_Id);
6fb4cdde
AC		 134 -- N is the node for a logical operator. If the operator is predefined, and
135 -- the root type of the operands is Standard.Boolean, then a check is made
a36c1c3e
RD		 136 -- for restriction No_Direct_Boolean_Operators. This procedure also handles
137 -- the style check for Style_Check_Boolean_And_Or.
f61580d4 138
67ce0d7e 139 function Is_Definite_Access_Type (E : Entity_Id) return Boolean;
5cc9353d
RD		 140 -- Determine whether E is an access type declared by an access declaration,
141 -- and not an (anonymous) allocator type.
67ce0d7e 142
996ae0b0 143 function Is_Predefined_Op (Nam : Entity_Id) return Boolean;
6a497607
AC		 144 -- Utility to check whether the entity for an operator is a predefined
145 -- operator, in which case the expression is left as an operator in the
146 -- tree (else it is rewritten into a call). An instance of an intrinsic
147 -- conversion operation may be given an operator name, but is not treated
148 -- like an operator. Note that an operator that is an imported back-end
149 -- builtin has convention Intrinsic, but is expected to be rewritten into
150 -- a call, so such an operator is not treated as predefined by this
151 -- predicate.
996ae0b0
RK		 152
153 procedure Replace_Actual_Discriminants (N : Node_Id; Default : Node_Id);
154 -- If a default expression in entry call N depends on the discriminants
155 -- of the task, it must be replaced with a reference to the discriminant
156 -- of the task being called.
157
10303118
BD		 158 procedure Resolve_Op_Concat_Arg
159 (N : Node_Id;
160 Arg : Node_Id;
161 Typ : Entity_Id;
162 Is_Comp : Boolean);
163 -- Internal procedure for Resolve_Op_Concat to resolve one operand of
164 -- concatenation operator. The operand is either of the array type or of
165 -- the component type. If the operand is an aggregate, and the component
166 -- type is composite, this is ambiguous if component type has aggregates.
167
168 procedure Resolve_Op_Concat_First (N : Node_Id; Typ : Entity_Id);
169 -- Does the first part of the work of Resolve_Op_Concat
170
171 procedure Resolve_Op_Concat_Rest (N : Node_Id; Typ : Entity_Id);
172 -- Does the "rest" of the work of Resolve_Op_Concat, after the left operand
173 -- has been resolved. See Resolve_Op_Concat for details.
174
996ae0b0
RK		 175 procedure Resolve_Allocator (N : Node_Id; Typ : Entity_Id);
176 procedure Resolve_Arithmetic_Op (N : Node_Id; Typ : Entity_Id);
177 procedure Resolve_Call (N : Node_Id; Typ : Entity_Id);
19d846a0 178 procedure Resolve_Case_Expression (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 179 procedure Resolve_Character_Literal (N : Node_Id; Typ : Entity_Id);
180 procedure Resolve_Comparison_Op (N : Node_Id; Typ : Entity_Id);
181 procedure Resolve_Conditional_Expression (N : Node_Id; Typ : Entity_Id);
955871d3 182 procedure Resolve_Entity_Name (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 183 procedure Resolve_Equality_Op (N : Node_Id; Typ : Entity_Id);
184 procedure Resolve_Explicit_Dereference (N : Node_Id; Typ : Entity_Id);
955871d3 185 procedure Resolve_Expression_With_Actions (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 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_Range (N : Node_Id; Typ : Entity_Id);
197 procedure Resolve_Real_Literal (N : Node_Id; Typ : Entity_Id);
198 procedure Resolve_Reference (N : Node_Id; Typ : Entity_Id);
199 procedure Resolve_Selected_Component (N : Node_Id; Typ : Entity_Id);
200 procedure Resolve_Shift (N : Node_Id; Typ : Entity_Id);
201 procedure Resolve_Short_Circuit (N : Node_Id; Typ : Entity_Id);
202 procedure Resolve_Slice (N : Node_Id; Typ : Entity_Id);
203 procedure Resolve_String_Literal (N : Node_Id; Typ : Entity_Id);
204 procedure Resolve_Subprogram_Info (N : Node_Id; Typ : Entity_Id);
205 procedure Resolve_Type_Conversion (N : Node_Id; Typ : Entity_Id);
206 procedure Resolve_Unary_Op (N : Node_Id; Typ : Entity_Id);
207 procedure Resolve_Unchecked_Expression (N : Node_Id; Typ : Entity_Id);
208 procedure Resolve_Unchecked_Type_Conversion (N : Node_Id; Typ : Entity_Id);
209
210 function Operator_Kind
211 (Op_Name : Name_Id;
0ab80019 212 Is_Binary : Boolean) return Node_Kind;
996ae0b0
RK		 213 -- Utility to map the name of an operator into the corresponding Node. Used
214 -- by other node rewriting procedures.
215
216 procedure Resolve_Actuals (N : Node_Id; Nam : Entity_Id);
bc5f3720
RD		 217 -- Resolve actuals of call, and add default expressions for missing ones.
218 -- N is the Node_Id for the subprogram call, and Nam is the entity of the
219 -- called subprogram.
996ae0b0
RK		 220
221 procedure Resolve_Entry_Call (N : Node_Id; Typ : Entity_Id);
222 -- Called from Resolve_Call, when the prefix denotes an entry or element
223 -- of entry family. Actuals are resolved as for subprograms, and the node
224 -- is rebuilt as an entry call. Also called for protected operations. Typ
225 -- is the context type, which is used when the operation is a protected
226 -- function with no arguments, and the return value is indexed.
227
228 procedure Resolve_Intrinsic_Operator (N : Node_Id; Typ : Entity_Id);
5cc9353d
RD		 229 -- A call to a user-defined intrinsic operator is rewritten as a call to
230 -- the corresponding predefined operator, with suitable conversions. Note
231 -- that this applies only for intrinsic operators that denote predefined
232 -- operators, not ones that are intrinsic imports of back-end builtins.
996ae0b0 233
fbf5a39b 234 procedure Resolve_Intrinsic_Unary_Operator (N : Node_Id; Typ : Entity_Id);
305caf42
AC		 235 -- Ditto, for unary operators (arithmetic ones and "not" on signed
236 -- integer types for VMS).
fbf5a39b 237
996ae0b0
RK		 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.
241
242 procedure Make_Call_Into_Operator
243 (N : Node_Id;
244 Typ : Entity_Id;
245 Op_Id : Entity_Id);
246 -- Inverse transformation: if an operator is given in functional notation,
247 -- then after resolving the node, transform into an operator node, so
248 -- that operands are resolved properly. Recall that predefined operators
249 -- do not have a full signature and special resolution rules apply.
250
0ab80019
AC		 251 procedure Rewrite_Renamed_Operator
252 (N : Node_Id;
253 Op : Entity_Id;
254 Typ : Entity_Id);
996ae0b0 255 -- An operator can rename another, e.g. in an instantiation. In that
0ab80019 256 -- case, the proper operator node must be constructed and resolved.
996ae0b0
RK		 257
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
07fc65c4
GB		 260 -- operands of a static concatenation operation. If the argument is
261 -- not a N_String_Literal node, then the call has no effect.
996ae0b0
RK		 262
263 procedure Set_Slice_Subtype (N : Node_Id);
fbf5a39b 264 -- Build subtype of array type, with the range specified by the slice
996ae0b0 265
0669bebe
GB		 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 Truncation attribute.
270
996ae0b0 271 function Unique_Fixed_Point_Type (N : Node_Id) return Entity_Id;
5cc9353d
RD		 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).
996ae0b0 276
996ae0b0
RK		 277 -------------------------
278 -- Ambiguous_Character --
279 -------------------------
280
281 procedure Ambiguous_Character (C : Node_Id) is
282 E : Entity_Id;
283
284 begin
285 if Nkind (C) = N_Character_Literal then
ed2233dc 286 Error_Msg_N ("ambiguous character literal", C);
b7d1f17f
HK		 287
288 -- First the ones in Standard
289
ed2233dc
AC		 290 Error_Msg_N ("\\possible interpretation: Character!", C);
291 Error_Msg_N ("\\possible interpretation: Wide_Character!", C);
b7d1f17f
HK		 292
293 -- Include Wide_Wide_Character in Ada 2005 mode
294
0791fbe9 295 if Ada_Version >= Ada_2005 then
ed2233dc 296 Error_Msg_N ("\\possible interpretation: Wide_Wide_Character!", C);
b7d1f17f
HK		 297 end if;
298
299 -- Now any other types that match
996ae0b0
RK		 300
301 E := Current_Entity (C);
1420b484 302 while Present (E) loop
ed2233dc 303 Error_Msg_NE ("\\possible interpretation:}!", C, Etype (E));
1420b484
JM		 304 E := Homonym (E);
305 end loop;
996ae0b0
RK		 306 end if;
307 end Ambiguous_Character;
308
309 -------------------------
310 -- Analyze_And_Resolve --
311 -------------------------
312
313 procedure Analyze_And_Resolve (N : Node_Id) is
314 begin
315 Analyze (N);
fbf5a39b 316 Resolve (N);
996ae0b0
RK		 317 end Analyze_And_Resolve;
318
319 procedure Analyze_And_Resolve (N : Node_Id; Typ : Entity_Id) is
320 begin
321 Analyze (N);
322 Resolve (N, Typ);
323 end Analyze_And_Resolve;
324
325 -- Version withs check(s) suppressed
326
327 procedure Analyze_And_Resolve
328 (N : Node_Id;
329 Typ : Entity_Id;
330 Suppress : Check_Id)
331 is
fbf5a39b 332 Scop : constant Entity_Id := Current_Scope;
996ae0b0
RK		 333
334 begin
335 if Suppress = All_Checks then
336 declare
fbf5a39b 337 Svg : constant Suppress_Array := Scope_Suppress;
996ae0b0
RK		 338 begin
339 Scope_Suppress := (others => True);
340 Analyze_And_Resolve (N, Typ);
341 Scope_Suppress := Svg;
342 end;
343
344 else
345 declare
fbf5a39b 346 Svg : constant Boolean := Scope_Suppress (Suppress);
996ae0b0
RK		 347
348 begin
fbf5a39b 349 Scope_Suppress (Suppress) := True;
996ae0b0 350 Analyze_And_Resolve (N, Typ);
fbf5a39b 351 Scope_Suppress (Suppress) := Svg;
996ae0b0
RK		 352 end;
353 end if;
354
355 if Current_Scope /= Scop
356 and then Scope_Is_Transient
357 then
5cc9353d
RD		 358 -- This can only happen if a transient scope was created for an inner
359 -- expression, which will be removed upon completion of the analysis
360 -- of an enclosing construct. The transient scope must have the
361 -- suppress status of the enclosing environment, not of this Analyze
362 -- call.
996ae0b0
RK		 363
364 Scope_Stack.Table (Scope_Stack.Last).Save_Scope_Suppress :=
365 Scope_Suppress;
366 end if;
367 end Analyze_And_Resolve;
368
369 procedure Analyze_And_Resolve
370 (N : Node_Id;
371 Suppress : Check_Id)
372 is
fbf5a39b 373 Scop : constant Entity_Id := Current_Scope;
996ae0b0
RK		 374
375 begin
376 if Suppress = All_Checks then
377 declare
fbf5a39b 378 Svg : constant Suppress_Array := Scope_Suppress;
996ae0b0
RK		 379 begin
380 Scope_Suppress := (others => True);
381 Analyze_And_Resolve (N);
382 Scope_Suppress := Svg;
383 end;
384
385 else
386 declare
fbf5a39b 387 Svg : constant Boolean := Scope_Suppress (Suppress);
996ae0b0
RK		 388
389 begin
fbf5a39b 390 Scope_Suppress (Suppress) := True;
996ae0b0 391 Analyze_And_Resolve (N);
fbf5a39b 392 Scope_Suppress (Suppress) := Svg;
996ae0b0
RK		 393 end;
394 end if;
395
396 if Current_Scope /= Scop
397 and then Scope_Is_Transient
398 then
399 Scope_Stack.Table (Scope_Stack.Last).Save_Scope_Suppress :=
400 Scope_Suppress;
401 end if;
402 end Analyze_And_Resolve;
403
bd29d519
AC		 404 ----------------------------------------
405 -- Bad_Unordered_Enumeration_Reference --
406 ----------------------------------------
407
408 function Bad_Unordered_Enumeration_Reference
409 (N : Node_Id;
410 T : Entity_Id) return Boolean
411 is
412 begin
413 return Is_Enumeration_Type (T)
414 and then Comes_From_Source (N)
415 and then Warn_On_Unordered_Enumeration_Type
416 and then not Has_Pragma_Ordered (T)
417 and then not In_Same_Extended_Unit (N, T);
418 end Bad_Unordered_Enumeration_Reference;
419
996ae0b0
RK		 420 ----------------------------
421 -- Check_Discriminant_Use --
422 ----------------------------
423
424 procedure Check_Discriminant_Use (N : Node_Id) is
425 PN : constant Node_Id := Parent (N);
426 Disc : constant Entity_Id := Entity (N);
427 P : Node_Id;
428 D : Node_Id;
429
430 begin
f3d0f304 431 -- Any use in a spec-expression is legal
996ae0b0 432
45fc7ddb 433 if In_Spec_Expression then
996ae0b0
RK		 434 null;
435
436 elsif Nkind (PN) = N_Range then
437
a77842bd 438 -- Discriminant cannot be used to constrain a scalar type
996ae0b0
RK		 439
440 P := Parent (PN);
441
442 if Nkind (P) = N_Range_Constraint
443 and then Nkind (Parent (P)) = N_Subtype_Indication
a397db96 444 and then Nkind (Parent (Parent (P))) = N_Component_Definition
996ae0b0
RK		 445 then
446 Error_Msg_N ("discriminant cannot constrain scalar type", N);
447
448 elsif Nkind (P) = N_Index_Or_Discriminant_Constraint then
449
5cc9353d
RD		 450 -- The following check catches the unusual case where a
451 -- discriminant appears within an index constraint that is part of
452 -- a larger expression within a constraint on a component, e.g. "C
453 -- : Int range 1 .. F (new A(1 .. D))". For now we only check case
454 -- of record components, and note that a similar check should also
455 -- apply in the case of discriminant constraints below. ???
996ae0b0
RK		 456
457 -- Note that the check for N_Subtype_Declaration below is to
458 -- detect the valid use of discriminants in the constraints of a
459 -- subtype declaration when this subtype declaration appears
460 -- inside the scope of a record type (which is syntactically
461 -- illegal, but which may be created as part of derived type
462 -- processing for records). See Sem_Ch3.Build_Derived_Record_Type
463 -- for more info.
464
465 if Ekind (Current_Scope) = E_Record_Type
466 and then Scope (Disc) = Current_Scope
467 and then not
468 (Nkind (Parent (P)) = N_Subtype_Indication
45fc7ddb
HK		 469 and then
470 Nkind_In (Parent (Parent (P)), N_Component_Definition,
471 N_Subtype_Declaration)
996ae0b0
RK		 472 and then Paren_Count (N) = 0)
473 then
474 Error_Msg_N
475 ("discriminant must appear alone in component constraint", N);
476 return;
477 end if;
478
a0ac3932 479 -- Detect a common error:
9bc43c53 480
996ae0b0 481 -- type R (D : Positive := 100) is record
9bc43c53 482 -- Name : String (1 .. D);
996ae0b0
RK		 483 -- end record;
484
a0ac3932
RD		 485 -- The default value causes an object of type R to be allocated
486 -- with room for Positive'Last characters. The RM does not mandate
487 -- the allocation of the maximum size, but that is what GNAT does
488 -- so we should warn the programmer that there is a problem.
996ae0b0 489
a0ac3932 490 Check_Large : declare
996ae0b0
RK		 491 SI : Node_Id;
492 T : Entity_Id;
493 TB : Node_Id;
494 CB : Entity_Id;
495
496 function Large_Storage_Type (T : Entity_Id) return Boolean;
5cc9353d
RD		 497 -- Return True if type T has a large enough range that any
498 -- array whose index type covered the whole range of the type
499 -- would likely raise Storage_Error.
996ae0b0 500
fbf5a39b
AC		 501 ------------------------
502 -- Large_Storage_Type --
503 ------------------------
504
996ae0b0
RK		 505 function Large_Storage_Type (T : Entity_Id) return Boolean is
506 begin
4b92fd3c
ST		 507 -- The type is considered large if its bounds are known at
508 -- compile time and if it requires at least as many bits as
509 -- a Positive to store the possible values.
510
511 return Compile_Time_Known_Value (Type_Low_Bound (T))
512 and then Compile_Time_Known_Value (Type_High_Bound (T))
513 and then
514 Minimum_Size (T, Biased => True) >=
a0ac3932 515 RM_Size (Standard_Positive);
996ae0b0
RK		 516 end Large_Storage_Type;
517
a0ac3932
RD		 518 -- Start of processing for Check_Large
519
996ae0b0
RK		 520 begin
521 -- Check that the Disc has a large range
522
523 if not Large_Storage_Type (Etype (Disc)) then
524 goto No_Danger;
525 end if;
526
527 -- If the enclosing type is limited, we allocate only the
528 -- default value, not the maximum, and there is no need for
529 -- a warning.
530
531 if Is_Limited_Type (Scope (Disc)) then
532 goto No_Danger;
533 end if;
534
535 -- Check that it is the high bound
536
537 if N /= High_Bound (PN)
c8ef728f 538 or else No (Discriminant_Default_Value (Disc))
996ae0b0
RK		 539 then
540 goto No_Danger;
541 end if;
542
5cc9353d
RD		 543 -- Check the array allows a large range at this bound. First
544 -- find the array
996ae0b0
RK		 545
546 SI := Parent (P);
547
548 if Nkind (SI) /= N_Subtype_Indication then
549 goto No_Danger;
550 end if;
551
552 T := Entity (Subtype_Mark (SI));
553
554 if not Is_Array_Type (T) then
555 goto No_Danger;
556 end if;
557
558 -- Next, find the dimension
559
560 TB := First_Index (T);
561 CB := First (Constraints (P));
562 while True
563 and then Present (TB)
564 and then Present (CB)
565 and then CB /= PN
566 loop
567 Next_Index (TB);
568 Next (CB);
569 end loop;
570
571 if CB /= PN then
572 goto No_Danger;
573 end if;
574
575 -- Now, check the dimension has a large range
576
577 if not Large_Storage_Type (Etype (TB)) then
578 goto No_Danger;
579 end if;
580
581 -- Warn about the danger
582
583 Error_Msg_N
aa5147f0 584 ("?creation of & object may raise Storage_Error!",
fbf5a39b 585 Scope (Disc));
996ae0b0
RK		 586
587 <<No_Danger>>
588 null;
589
a0ac3932 590 end Check_Large;
996ae0b0
RK		 591 end if;
592
593 -- Legal case is in index or discriminant constraint
594
45fc7ddb
HK		 595 elsif Nkind_In (PN, N_Index_Or_Discriminant_Constraint,
596 N_Discriminant_Association)
996ae0b0
RK		 597 then
598 if Paren_Count (N) > 0 then
599 Error_Msg_N
600 ("discriminant in constraint must appear alone", N);
758c442c
GD		 601
602 elsif Nkind (N) = N_Expanded_Name
603 and then Comes_From_Source (N)
604 then
605 Error_Msg_N
606 ("discriminant must appear alone as a direct name", N);
996ae0b0
RK		 607 end if;
608
609 return;
610
5cc9353d
RD		 611 -- Otherwise, context is an expression. It should not be within (i.e. a
612 -- subexpression of) a constraint for a component.
996ae0b0
RK		 613
614 else
615 D := PN;
616 P := Parent (PN);
45fc7ddb
HK		 617 while not Nkind_In (P, N_Component_Declaration,
618 N_Subtype_Indication,
619 N_Entry_Declaration)
996ae0b0
RK		 620 loop
621 D := P;
622 P := Parent (P);
623 exit when No (P);
624 end loop;
625
5cc9353d
RD		 626 -- If the discriminant is used in an expression that is a bound of a
627 -- scalar type, an Itype is created and the bounds are attached to
628 -- its range, not to the original subtype indication. Such use is of
629 -- course a double fault.
996ae0b0
RK		 630
631 if (Nkind (P) = N_Subtype_Indication
45fc7ddb
HK		 632 and then Nkind_In (Parent (P), N_Component_Definition,
633 N_Derived_Type_Definition)
996ae0b0
RK		 634 and then D = Constraint (P))
635
19fb051c
AC		 636 -- The constraint itself may be given by a subtype indication,
637 -- rather than by a more common discrete range.
996ae0b0
RK		 638
639 or else (Nkind (P) = N_Subtype_Indication
fbf5a39b
AC		 640 and then
641 Nkind (Parent (P)) = N_Index_Or_Discriminant_Constraint)
996ae0b0
RK		 642 or else Nkind (P) = N_Entry_Declaration
643 or else Nkind (D) = N_Defining_Identifier
644 then
645 Error_Msg_N
646 ("discriminant in constraint must appear alone", N);
647 end if;
648 end if;
649 end Check_Discriminant_Use;
650
651 --------------------------------
652 -- Check_For_Visible_Operator --
653 --------------------------------
654
655 procedure Check_For_Visible_Operator (N : Node_Id; T : Entity_Id) is
996ae0b0 656 begin
fbf5a39b 657 if Is_Invisible_Operator (N, T) then
305caf42 658 Error_Msg_NE -- CODEFIX
996ae0b0 659 ("operator for} is not directly visible!", N, First_Subtype (T));
305caf42
AC		 660 Error_Msg_N -- CODEFIX
661 ("use clause would make operation legal!", N);
996ae0b0
RK		 662 end if;
663 end Check_For_Visible_Operator;
664
c8ef728f
ES		 665 ----------------------------------
666 -- Check_Fully_Declared_Prefix --
667 ----------------------------------
668
669 procedure Check_Fully_Declared_Prefix
670 (Typ : Entity_Id;
671 Pref : Node_Id)
672 is
673 begin
674 -- Check that the designated type of the prefix of a dereference is
675 -- not an incomplete type. This cannot be done unconditionally, because
676 -- dereferences of private types are legal in default expressions. This
677 -- case is taken care of in Check_Fully_Declared, called below. There
678 -- are also 2005 cases where it is legal for the prefix to be unfrozen.
679
680 -- This consideration also applies to similar checks for allocators,
681 -- qualified expressions, and type conversions.
682
683 -- An additional exception concerns other per-object expressions that
684 -- are not directly related to component declarations, in particular
685 -- representation pragmas for tasks. These will be per-object
686 -- expressions if they depend on discriminants or some global entity.
687 -- If the task has access discriminants, the designated type may be
688 -- incomplete at the point the expression is resolved. This resolution
689 -- takes place within the body of the initialization procedure, where
690 -- the discriminant is replaced by its discriminal.
691
692 if Is_Entity_Name (Pref)
693 and then Ekind (Entity (Pref)) = E_In_Parameter
694 then
695 null;
696
697 -- Ada 2005 (AI-326): Tagged incomplete types allowed. The wrong usages
698 -- are handled by Analyze_Access_Attribute, Analyze_Assignment,
699 -- Analyze_Object_Renaming, and Freeze_Entity.
700
0791fbe9 701 elsif Ada_Version >= Ada_2005
c8ef728f 702 and then Is_Entity_Name (Pref)
811c6a85 703 and then Is_Access_Type (Etype (Pref))
c8ef728f
ES		 704 and then Ekind (Directly_Designated_Type (Etype (Pref))) =
705 E_Incomplete_Type
706 and then Is_Tagged_Type (Directly_Designated_Type (Etype (Pref)))
707 then
708 null;
709 else
710 Check_Fully_Declared (Typ, Parent (Pref));
711 end if;
712 end Check_Fully_Declared_Prefix;
713
996ae0b0
RK		 714 ------------------------------
715 -- Check_Infinite_Recursion --
716 ------------------------------
717
718 function Check_Infinite_Recursion (N : Node_Id) return Boolean is
719 P : Node_Id;
720 C : Node_Id;
721
07fc65c4 722 function Same_Argument_List return Boolean;
5cc9353d
RD		 723 -- Check whether list of actuals is identical to list of formals of
724 -- called function (which is also the enclosing scope).
07fc65c4
GB		 725
726 ------------------------
727 -- Same_Argument_List --
728 ------------------------
729
730 function Same_Argument_List return Boolean is
731 A : Node_Id;
732 F : Entity_Id;
733 Subp : Entity_Id;
734
735 begin
736 if not Is_Entity_Name (Name (N)) then
737 return False;
738 else
739 Subp := Entity (Name (N));
740 end if;
741
742 F := First_Formal (Subp);
743 A := First_Actual (N);
07fc65c4
GB		 744 while Present (F) and then Present (A) loop
745 if not Is_Entity_Name (A)
746 or else Entity (A) /= F
747 then
748 return False;
749 end if;
750
751 Next_Actual (A);
752 Next_Formal (F);
753 end loop;
754
755 return True;
756 end Same_Argument_List;
757
758 -- Start of processing for Check_Infinite_Recursion
759
996ae0b0 760 begin
26570b21
RD		 761 -- Special case, if this is a procedure call and is a call to the
762 -- current procedure with the same argument list, then this is for
763 -- sure an infinite recursion and we insert a call to raise SE.
764
765 if Is_List_Member (N)
766 and then List_Length (List_Containing (N)) = 1
767 and then Same_Argument_List
768 then
769 declare
770 P : constant Node_Id := Parent (N);
771 begin
772 if Nkind (P) = N_Handled_Sequence_Of_Statements
773 and then Nkind (Parent (P)) = N_Subprogram_Body
774 and then Is_Empty_List (Declarations (Parent (P)))
775 then
776 Error_Msg_N ("!?infinite recursion", N);
777 Error_Msg_N ("\!?Storage_Error will be raised at run time", N);
778 Insert_Action (N,
779 Make_Raise_Storage_Error (Sloc (N),
780 Reason => SE_Infinite_Recursion));
781 return True;
782 end if;
783 end;
784 end if;
785
786 -- If not that special case, search up tree, quitting if we reach a
787 -- construct (e.g. a conditional) that tells us that this is not a
788 -- case for an infinite recursion warning.
996ae0b0
RK		 789
790 C := N;
791 loop
792 P := Parent (C);
9a7da240
RD		 793
794 -- If no parent, then we were not inside a subprogram, this can for
795 -- example happen when processing certain pragmas in a spec. Just
796 -- return False in this case.
797
798 if No (P) then
799 return False;
800 end if;
801
802 -- Done if we get to subprogram body, this is definitely an infinite
803 -- recursion case if we did not find anything to stop us.
804
996ae0b0 805 exit when Nkind (P) = N_Subprogram_Body;
9a7da240
RD		 806
807 -- If appearing in conditional, result is false
808
45fc7ddb
HK		 809 if Nkind_In (P, N_Or_Else,
810 N_And_Then,
d347f572
AC		 811 N_Case_Expression,
812 N_Case_Statement,
813 N_Conditional_Expression,
814 N_If_Statement)
996ae0b0
RK		 815 then
816 return False;
817
818 elsif Nkind (P) = N_Handled_Sequence_Of_Statements
819 and then C /= First (Statements (P))
820 then
26570b21
RD		 821 -- If the call is the expression of a return statement and the
822 -- actuals are identical to the formals, it's worth a warning.
823 -- However, we skip this if there is an immediately preceding
824 -- raise statement, since the call is never executed.
07fc65c4
GB		 825
826 -- Furthermore, this corresponds to a common idiom:
827
828 -- function F (L : Thing) return Boolean is
829 -- begin
830 -- raise Program_Error;
831 -- return F (L);
832 -- end F;
833
834 -- for generating a stub function
835
aa5147f0 836 if Nkind (Parent (N)) = N_Simple_Return_Statement
07fc65c4
GB		 837 and then Same_Argument_List
838 then
9ebe3743
HK		 839 exit when not Is_List_Member (Parent (N));
840
841 -- OK, return statement is in a statement list, look for raise
842
843 declare
844 Nod : Node_Id;
845
846 begin
847 -- Skip past N_Freeze_Entity nodes generated by expansion
848
849 Nod := Prev (Parent (N));
850 while Present (Nod)
851 and then Nkind (Nod) = N_Freeze_Entity
852 loop
853 Prev (Nod);
854 end loop;
855
3235dc87
AC		 856 -- If no raise statement, give warning. We look at the
857 -- original node, because in the case of "raise ... with
858 -- ...", the node has been transformed into a call.
9ebe3743 859
3235dc87 860 exit when Nkind (Original_Node (Nod)) /= N_Raise_Statement
9ebe3743
HK		 861 and then
862 (Nkind (Nod) not in N_Raise_xxx_Error
19fb051c 863 or else Present (Condition (Nod)));
9ebe3743 864 end;
07fc65c4
GB		 865 end if;
866
996ae0b0
RK		 867 return False;
868
869 else
870 C := P;
871 end if;
872 end loop;
873
aa5147f0
ES		 874 Error_Msg_N ("!?possible infinite recursion", N);
875 Error_Msg_N ("\!?Storage_Error may be raised at run time", N);
996ae0b0
RK		 876
877 return True;
878 end Check_Infinite_Recursion;
879
880 -------------------------------
881 -- Check_Initialization_Call --
882 -------------------------------
883
884 procedure Check_Initialization_Call (N : Entity_Id; Nam : Entity_Id) is
fbf5a39b 885 Typ : constant Entity_Id := Etype (First_Formal (Nam));
996ae0b0
RK		 886
887 function Uses_SS (T : Entity_Id) return Boolean;
07fc65c4
GB		 888 -- Check whether the creation of an object of the type will involve
889 -- use of the secondary stack. If T is a record type, this is true
f3d57416 890 -- if the expression for some component uses the secondary stack, e.g.
07fc65c4
GB		 891 -- through a call to a function that returns an unconstrained value.
892 -- False if T is controlled, because cleanups occur elsewhere.
893
894 -------------
895 -- Uses_SS --
896 -------------
996ae0b0
RK		 897
898 function Uses_SS (T : Entity_Id) return Boolean is
aa5147f0
ES		 899 Comp : Entity_Id;
900 Expr : Node_Id;
901 Full_Type : Entity_Id := Underlying_Type (T);
996ae0b0
RK		 902
903 begin
aa5147f0
ES		 904 -- Normally we want to use the underlying type, but if it's not set
905 -- then continue with T.
906
907 if not Present (Full_Type) then
908 Full_Type := T;
909 end if;
910
911 if Is_Controlled (Full_Type) then
996ae0b0
RK		 912 return False;
913
aa5147f0
ES		 914 elsif Is_Array_Type (Full_Type) then
915 return Uses_SS (Component_Type (Full_Type));
996ae0b0 916
aa5147f0
ES		 917 elsif Is_Record_Type (Full_Type) then
918 Comp := First_Component (Full_Type);
996ae0b0 919 while Present (Comp) loop
996ae0b0
RK		 920 if Ekind (Comp) = E_Component
921 and then Nkind (Parent (Comp)) = N_Component_Declaration
922 then
aa5147f0
ES		 923 -- The expression for a dynamic component may be rewritten
924 -- as a dereference, so retrieve original node.
925
926 Expr := Original_Node (Expression (Parent (Comp)));
996ae0b0 927
aa5147f0 928 -- Return True if the expression is a call to a function
1d57c04f
AC		 929 -- (including an attribute function such as Image, or a
930 -- user-defined operator) with a result that requires a
931 -- transient scope.
fbf5a39b 932
aa5147f0 933 if (Nkind (Expr) = N_Function_Call
1d57c04f 934 or else Nkind (Expr) in N_Op
aa5147f0
ES		 935 or else (Nkind (Expr) = N_Attribute_Reference
936 and then Present (Expressions (Expr))))
996ae0b0
RK		 937 and then Requires_Transient_Scope (Etype (Expr))
938 then
939 return True;
940
941 elsif Uses_SS (Etype (Comp)) then
942 return True;
943 end if;
944 end if;
945
946 Next_Component (Comp);
947 end loop;
948
949 return False;
950
951 else
952 return False;
953 end if;
954 end Uses_SS;
955
07fc65c4
GB		 956 -- Start of processing for Check_Initialization_Call
957
996ae0b0 958 begin
0669bebe 959 -- Establish a transient scope if the type needs it
07fc65c4 960
0669bebe 961 if Uses_SS (Typ) then
996ae0b0
RK		 962 Establish_Transient_Scope (First_Actual (N), Sec_Stack => True);
963 end if;
964 end Check_Initialization_Call;
965
f61580d4
AC		 966 ---------------------------------------
967 -- Check_No_Direct_Boolean_Operators --
968 ---------------------------------------
969
970 procedure Check_No_Direct_Boolean_Operators (N : Node_Id) is
971 begin
972 if Scope (Entity (N)) = Standard_Standard
973 and then Root_Type (Etype (Left_Opnd (N))) = Standard_Boolean
974 then
6fb4cdde 975 -- Restriction only applies to original source code
f61580d4 976
6fb4cdde 977 if Comes_From_Source (N) then
f61580d4
AC		 978 Check_Restriction (No_Direct_Boolean_Operators, N);
979 end if;
980 end if;
a36c1c3e
RD		 981
982 if Style_Check then
983 Check_Boolean_Operator (N);
984 end if;
f61580d4
AC		 985 end Check_No_Direct_Boolean_Operators;
986
996ae0b0
RK		 987 ------------------------------
988 -- Check_Parameterless_Call --
989 ------------------------------
990
991 procedure Check_Parameterless_Call (N : Node_Id) is
992 Nam : Node_Id;
993
bc5f3720
RD		 994 function Prefix_Is_Access_Subp return Boolean;
995 -- If the prefix is of an access_to_subprogram type, the node must be
996 -- rewritten as a call. Ditto if the prefix is overloaded and all its
997 -- interpretations are access to subprograms.
998
999 ---------------------------
1000 -- Prefix_Is_Access_Subp --
1001 ---------------------------
1002
1003 function Prefix_Is_Access_Subp return Boolean is
1004 I : Interp_Index;
1005 It : Interp;
1006
1007 begin
22b77f68 1008 -- If the context is an attribute reference that can apply to
b4a4936b 1009 -- functions, this is never a parameterless call (RM 4.1.4(6)).
96d2756f
AC		 1010
1011 if Nkind (Parent (N)) = N_Attribute_Reference
19fb051c
AC		 1012 and then (Attribute_Name (Parent (N)) = Name_Address or else
1013 Attribute_Name (Parent (N)) = Name_Code_Address or else
1014 Attribute_Name (Parent (N)) = Name_Access)
96d2756f
AC		 1015 then
1016 return False;
1017 end if;
1018
bc5f3720
RD		 1019 if not Is_Overloaded (N) then
1020 return
1021 Ekind (Etype (N)) = E_Subprogram_Type
1022 and then Base_Type (Etype (Etype (N))) /= Standard_Void_Type;
1023 else
1024 Get_First_Interp (N, I, It);
1025 while Present (It.Typ) loop
1026 if Ekind (It.Typ) /= E_Subprogram_Type
1027 or else Base_Type (Etype (It.Typ)) = Standard_Void_Type
1028 then
1029 return False;
1030 end if;
1031
1032 Get_Next_Interp (I, It);
1033 end loop;
1034
1035 return True;
1036 end if;
1037 end Prefix_Is_Access_Subp;
1038
1039 -- Start of processing for Check_Parameterless_Call
1040
996ae0b0 1041 begin
07fc65c4
GB		 1042 -- Defend against junk stuff if errors already detected
1043
1044 if Total_Errors_Detected /= 0 then
1045 if Nkind (N) in N_Has_Etype and then Etype (N) = Any_Type then
1046 return;
1047 elsif Nkind (N) in N_Has_Chars
1048 and then Chars (N) in Error_Name_Or_No_Name
1049 then
1050 return;
1051 end if;
fbf5a39b
AC		 1052
1053 Require_Entity (N);
996ae0b0
RK		 1054 end if;
1055
45fc7ddb
HK		 1056 -- If the context expects a value, and the name is a procedure, this is
1057 -- most likely a missing 'Access. Don't try to resolve the parameterless
1058 -- call, error will be caught when the outer call is analyzed.
18c0ecbe
AC		 1059
1060 if Is_Entity_Name (N)
1061 and then Ekind (Entity (N)) = E_Procedure
1062 and then not Is_Overloaded (N)
1063 and then
45fc7ddb
HK		 1064 Nkind_In (Parent (N), N_Parameter_Association,
1065 N_Function_Call,
1066 N_Procedure_Call_Statement)
18c0ecbe
AC		 1067 then
1068 return;
1069 end if;
1070
45fc7ddb
HK		 1071 -- Rewrite as call if overloadable entity that is (or could be, in the
1072 -- overloaded case) a function call. If we know for sure that the entity
1073 -- is an enumeration literal, we do not rewrite it.
f4b049db 1074
e1d9659d
AC		 1075 -- If the entity is the name of an operator, it cannot be a call because
1076 -- operators cannot have default parameters. In this case, this must be
1077 -- a string whose contents coincide with an operator name. Set the kind
96d2756f 1078 -- of the node appropriately.
996ae0b0
RK		 1079
1080 if (Is_Entity_Name (N)
e1d9659d 1081 and then Nkind (N) /= N_Operator_Symbol
996ae0b0
RK		 1082 and then Is_Overloadable (Entity (N))
1083 and then (Ekind (Entity (N)) /= E_Enumeration_Literal
964f13da 1084 or else Is_Overloaded (N)))
996ae0b0 1085
09494c32 1086 -- Rewrite as call if it is an explicit dereference of an expression of
f3d57416 1087 -- a subprogram access type, and the subprogram type is not that of a
996ae0b0
RK		 1088 -- procedure or entry.
1089
1090 or else
bc5f3720 1091 (Nkind (N) = N_Explicit_Dereference and then Prefix_Is_Access_Subp)
996ae0b0
RK		 1092
1093 -- Rewrite as call if it is a selected component which is a function,
1094 -- this is the case of a call to a protected function (which may be
1095 -- overloaded with other protected operations).
1096
1097 or else
1098 (Nkind (N) = N_Selected_Component
1099 and then (Ekind (Entity (Selector_Name (N))) = E_Function
964f13da
RD		 1100 or else
1101 (Ekind_In (Entity (Selector_Name (N)), E_Entry,
1102 E_Procedure)
1103 and then Is_Overloaded (Selector_Name (N)))))
996ae0b0 1104
5cc9353d
RD		 1105 -- If one of the above three conditions is met, rewrite as call. Apply
1106 -- the rewriting only once.
996ae0b0
RK		 1107
1108 then
1109 if Nkind (Parent (N)) /= N_Function_Call
1110 or else N /= Name (Parent (N))
1111 then
747de90b
AC		 1112
1113 -- This may be a prefixed call that was not fully analyzed, e.g.
1114 -- an actual in an instance.
1115
1116 if Ada_Version >= Ada_2005
1117 and then Nkind (N) = N_Selected_Component
1118 and then Is_Dispatching_Operation (Entity (Selector_Name (N)))
1119 then
1120 Analyze_Selected_Component (N);
996c8821 1121
747de90b
AC		 1122 if Nkind (N) /= N_Selected_Component then
1123 return;
1124 end if;
1125 end if;
1126
996ae0b0
RK		 1127 Nam := New_Copy (N);
1128
bc5f3720 1129 -- If overloaded, overload set belongs to new copy
996ae0b0
RK		 1130
1131 Save_Interps (N, Nam);
1132
1133 -- Change node to parameterless function call (note that the
1134 -- Parameter_Associations associations field is left set to Empty,
1135 -- its normal default value since there are no parameters)
1136
1137 Change_Node (N, N_Function_Call);
1138 Set_Name (N, Nam);
1139 Set_Sloc (N, Sloc (Nam));
1140 Analyze_Call (N);
1141 end if;
1142
1143 elsif Nkind (N) = N_Parameter_Association then
1144 Check_Parameterless_Call (Explicit_Actual_Parameter (N));
e1d9659d
AC		 1145
1146 elsif Nkind (N) = N_Operator_Symbol then
1147 Change_Operator_Symbol_To_String_Literal (N);
1148 Set_Is_Overloaded (N, False);
1149 Set_Etype (N, Any_String);
996ae0b0
RK		 1150 end if;
1151 end Check_Parameterless_Call;
1152
67ce0d7e
RD		 1153 -----------------------------
1154 -- Is_Definite_Access_Type --
1155 -----------------------------
1156
1157 function Is_Definite_Access_Type (E : Entity_Id) return Boolean is
1158 Btyp : constant Entity_Id := Base_Type (E);
1159 begin
1160 return Ekind (Btyp) = E_Access_Type
1161 or else (Ekind (Btyp) = E_Access_Subprogram_Type
72e9f2b9 1162 and then Comes_From_Source (Btyp));
67ce0d7e
RD		 1163 end Is_Definite_Access_Type;
1164
996ae0b0
RK		 1165 ----------------------
1166 -- Is_Predefined_Op --
1167 ----------------------
1168
1169 function Is_Predefined_Op (Nam : Entity_Id) return Boolean is
1170 begin
6a497607
AC		 1171 -- Predefined operators are intrinsic subprograms
1172
1173 if not Is_Intrinsic_Subprogram (Nam) then
1174 return False;
1175 end if;
1176
1177 -- A call to a back-end builtin is never a predefined operator
1178
1179 if Is_Imported (Nam) and then Present (Interface_Name (Nam)) then
1180 return False;
1181 end if;
1182
1183 return not Is_Generic_Instance (Nam)
996ae0b0 1184 and then Chars (Nam) in Any_Operator_Name
6a497607 1185 and then (No (Alias (Nam)) or else Is_Predefined_Op (Alias (Nam)));
996ae0b0
RK		 1186 end Is_Predefined_Op;
1187
1188 -----------------------------
1189 -- Make_Call_Into_Operator --
1190 -----------------------------
1191
1192 procedure Make_Call_Into_Operator
1193 (N : Node_Id;
1194 Typ : Entity_Id;
1195 Op_Id : Entity_Id)
1196 is
1197 Op_Name : constant Name_Id := Chars (Op_Id);
1198 Act1 : Node_Id := First_Actual (N);
1199 Act2 : Node_Id := Next_Actual (Act1);
1200 Error : Boolean := False;
2820d220
AC		 1201 Func : constant Entity_Id := Entity (Name (N));
1202 Is_Binary : constant Boolean := Present (Act2);
996ae0b0
RK		 1203 Op_Node : Node_Id;
1204 Opnd_Type : Entity_Id;
1205 Orig_Type : Entity_Id := Empty;
1206 Pack : Entity_Id;
1207
1208 type Kind_Test is access function (E : Entity_Id) return Boolean;
1209
996ae0b0 1210 function Operand_Type_In_Scope (S : Entity_Id) return Boolean;
b4a4936b
AC		 1211 -- If the operand is not universal, and the operator is given by an
1212 -- expanded name, verify that the operand has an interpretation with a
1213 -- type defined in the given scope of the operator.
996ae0b0
RK		 1214
1215 function Type_In_P (Test : Kind_Test) return Entity_Id;
b4a4936b
AC		 1216 -- Find a type of the given class in package Pack that contains the
1217 -- operator.
996ae0b0 1218
996ae0b0
RK		 1219 ---------------------------
1220 -- Operand_Type_In_Scope --
1221 ---------------------------
1222
1223 function Operand_Type_In_Scope (S : Entity_Id) return Boolean is
1224 Nod : constant Node_Id := Right_Opnd (Op_Node);
1225 I : Interp_Index;
1226 It : Interp;
1227
1228 begin
1229 if not Is_Overloaded (Nod) then
1230 return Scope (Base_Type (Etype (Nod))) = S;
1231
1232 else
1233 Get_First_Interp (Nod, I, It);
996ae0b0 1234 while Present (It.Typ) loop
996ae0b0
RK		 1235 if Scope (Base_Type (It.Typ)) = S then
1236 return True;
1237 end if;
1238
1239 Get_Next_Interp (I, It);
1240 end loop;
1241
1242 return False;
1243 end if;
1244 end Operand_Type_In_Scope;
1245
1246 ---------------
1247 -- Type_In_P --
1248 ---------------
1249
1250 function Type_In_P (Test : Kind_Test) return Entity_Id is
1251 E : Entity_Id;
1252
1253 function In_Decl return Boolean;
1254 -- Verify that node is not part of the type declaration for the
1255 -- candidate type, which would otherwise be invisible.
1256
1257 -------------
1258 -- In_Decl --
1259 -------------
1260
1261 function In_Decl return Boolean is
1262 Decl_Node : constant Node_Id := Parent (E);
1263 N2 : Node_Id;
1264
1265 begin
1266 N2 := N;
1267
1268 if Etype (E) = Any_Type then
1269 return True;
1270
1271 elsif No (Decl_Node) then
1272 return False;
1273
1274 else
1275 while Present (N2)
1276 and then Nkind (N2) /= N_Compilation_Unit
1277 loop
1278 if N2 = Decl_Node then
1279 return True;
1280 else
1281 N2 := Parent (N2);
1282 end if;
1283 end loop;
1284
1285 return False;
1286 end if;
1287 end In_Decl;
1288
1289 -- Start of processing for Type_In_P
1290
1291 begin
b4a4936b
AC		 1292 -- If the context type is declared in the prefix package, this is the
1293 -- desired base type.
996ae0b0 1294
b4a4936b 1295 if Scope (Base_Type (Typ)) = Pack and then Test (Typ) then
996ae0b0
RK		 1296 return Base_Type (Typ);
1297
1298 else
1299 E := First_Entity (Pack);
996ae0b0 1300 while Present (E) loop
996ae0b0
RK		 1301 if Test (E)
1302 and then not In_Decl
1303 then
1304 return E;
1305 end if;
1306
1307 Next_Entity (E);
1308 end loop;
1309
1310 return Empty;
1311 end if;
1312 end Type_In_P;
1313
996ae0b0
RK		 1314 -- Start of processing for Make_Call_Into_Operator
1315
1316 begin
1317 Op_Node := New_Node (Operator_Kind (Op_Name, Is_Binary), Sloc (N));
1318
1319 -- Binary operator
1320
1321 if Is_Binary then
1322 Set_Left_Opnd (Op_Node, Relocate_Node (Act1));
1323 Set_Right_Opnd (Op_Node, Relocate_Node (Act2));
1324 Save_Interps (Act1, Left_Opnd (Op_Node));
1325 Save_Interps (Act2, Right_Opnd (Op_Node));
1326 Act1 := Left_Opnd (Op_Node);
1327 Act2 := Right_Opnd (Op_Node);
1328
1329 -- Unary operator
1330
1331 else
1332 Set_Right_Opnd (Op_Node, Relocate_Node (Act1));
1333 Save_Interps (Act1, Right_Opnd (Op_Node));
1334 Act1 := Right_Opnd (Op_Node);
1335 end if;
1336
1337 -- If the operator is denoted by an expanded name, and the prefix is
1338 -- not Standard, but the operator is a predefined one whose scope is
1339 -- Standard, then this is an implicit_operator, inserted as an
1340 -- interpretation by the procedure of the same name. This procedure
1341 -- overestimates the presence of implicit operators, because it does
1342 -- not examine the type of the operands. Verify now that the operand
1343 -- type appears in the given scope. If right operand is universal,
1344 -- check the other operand. In the case of concatenation, either
1345 -- argument can be the component type, so check the type of the result.
1346 -- If both arguments are literals, look for a type of the right kind
1347 -- defined in the given scope. This elaborate nonsense is brought to
1348 -- you courtesy of b33302a. The type itself must be frozen, so we must
1349 -- find the type of the proper class in the given scope.
1350
06f2efd7
TQ		 1351 -- A final wrinkle is the multiplication operator for fixed point types,
1352 -- which is defined in Standard only, and not in the scope of the
b4a4936b 1353 -- fixed point type itself.
996ae0b0
RK		 1354
1355 if Nkind (Name (N)) = N_Expanded_Name then
1356 Pack := Entity (Prefix (Name (N)));
1357
06f2efd7
TQ		 1358 -- If the entity being called is defined in the given package, it is
1359 -- a renaming of a predefined operator, and known to be legal.
996ae0b0
RK		 1360
1361 if Scope (Entity (Name (N))) = Pack
1362 and then Pack /= Standard_Standard
1363 then
1364 null;
1365
9ebe3743
HK		 1366 -- Visibility does not need to be checked in an instance: if the
1367 -- operator was not visible in the generic it has been diagnosed
1368 -- already, else there is an implicit copy of it in the instance.
1369
1370 elsif In_Instance then
1371 null;
1372
12577815 1373 elsif (Op_Name = Name_Op_Multiply or else Op_Name = Name_Op_Divide)
996ae0b0
RK		 1374 and then Is_Fixed_Point_Type (Etype (Left_Opnd (Op_Node)))
1375 and then Is_Fixed_Point_Type (Etype (Right_Opnd (Op_Node)))
1376 then
1377 if Pack /= Standard_Standard then
1378 Error := True;
1379 end if;
1380
b4a4936b 1381 -- Ada 2005 AI-420: Predefined equality on Universal_Access is
06f2efd7 1382 -- available.
c8ef728f 1383
0791fbe9 1384 elsif Ada_Version >= Ada_2005
c8ef728f
ES		 1385 and then (Op_Name = Name_Op_Eq or else Op_Name = Name_Op_Ne)
1386 and then Ekind (Etype (Act1)) = E_Anonymous_Access_Type
1387 then
1388 null;
1389
996ae0b0
RK		 1390 else
1391 Opnd_Type := Base_Type (Etype (Right_Opnd (Op_Node)));
1392
1393 if Op_Name = Name_Op_Concat then
1394 Opnd_Type := Base_Type (Typ);
1395
1396 elsif (Scope (Opnd_Type) = Standard_Standard
1397 and then Is_Binary)
1398 or else (Nkind (Right_Opnd (Op_Node)) = N_Attribute_Reference
1399 and then Is_Binary
1400 and then not Comes_From_Source (Opnd_Type))
1401 then
1402 Opnd_Type := Base_Type (Etype (Left_Opnd (Op_Node)));
1403 end if;
1404
1405 if Scope (Opnd_Type) = Standard_Standard then
1406
1407 -- Verify that the scope contains a type that corresponds to
1408 -- the given literal. Optimize the case where Pack is Standard.
1409
1410 if Pack /= Standard_Standard then
1411
1412 if Opnd_Type = Universal_Integer then
06f2efd7 1413 Orig_Type := Type_In_P (Is_Integer_Type'Access);
996ae0b0
RK		 1414
1415 elsif Opnd_Type = Universal_Real then
1416 Orig_Type := Type_In_P (Is_Real_Type'Access);
1417
1418 elsif Opnd_Type = Any_String then
1419 Orig_Type := Type_In_P (Is_String_Type'Access);
1420
1421 elsif Opnd_Type = Any_Access then
06f2efd7 1422 Orig_Type := Type_In_P (Is_Definite_Access_Type'Access);
996ae0b0
RK		 1423
1424 elsif Opnd_Type = Any_Composite then
1425 Orig_Type := Type_In_P (Is_Composite_Type'Access);
1426
1427 if Present (Orig_Type) then
1428 if Has_Private_Component (Orig_Type) then
1429 Orig_Type := Empty;
1430 else
1431 Set_Etype (Act1, Orig_Type);
1432
1433 if Is_Binary then
1434 Set_Etype (Act2, Orig_Type);
1435 end if;
1436 end if;
1437 end if;
1438
1439 else
1440 Orig_Type := Empty;
1441 end if;
1442
1443 Error := No (Orig_Type);
1444 end if;
1445
1446 elsif Ekind (Opnd_Type) = E_Allocator_Type
1447 and then No (Type_In_P (Is_Definite_Access_Type'Access))
1448 then
1449 Error := True;
1450
1451 -- If the type is defined elsewhere, and the operator is not
1452 -- defined in the given scope (by a renaming declaration, e.g.)
1453 -- then this is an error as well. If an extension of System is
1454 -- present, and the type may be defined there, Pack must be
1455 -- System itself.
1456
1457 elsif Scope (Opnd_Type) /= Pack
1458 and then Scope (Op_Id) /= Pack
1459 and then (No (System_Aux_Id)
1460 or else Scope (Opnd_Type) /= System_Aux_Id
1461 or else Pack /= Scope (System_Aux_Id))
1462 then
244e5a2c
AC		 1463 if not Is_Overloaded (Right_Opnd (Op_Node)) then
1464 Error := True;
1465 else
1466 Error := not Operand_Type_In_Scope (Pack);
1467 end if;
996ae0b0
RK		 1468
1469 elsif Pack = Standard_Standard
1470 and then not Operand_Type_In_Scope (Standard_Standard)
1471 then
1472 Error := True;
1473 end if;
1474 end if;
1475
1476 if Error then
1477 Error_Msg_Node_2 := Pack;
1478 Error_Msg_NE
1479 ("& not declared in&", N, Selector_Name (Name (N)));
1480 Set_Etype (N, Any_Type);
1481 return;
88b17d45
AC		 1482
1483 -- Detect a mismatch between the context type and the result type
1484 -- in the named package, which is otherwise not detected if the
1485 -- operands are universal. Check is only needed if source entity is
1486 -- an operator, not a function that renames an operator.
1487
1488 elsif Nkind (Parent (N)) /= N_Type_Conversion
1489 and then Ekind (Entity (Name (N))) = E_Operator
1490 and then Is_Numeric_Type (Typ)
1491 and then not Is_Universal_Numeric_Type (Typ)
1492 and then Scope (Base_Type (Typ)) /= Pack
1493 and then not In_Instance
1494 then
1495 if Is_Fixed_Point_Type (Typ)
1496 and then (Op_Name = Name_Op_Multiply
1497 or else
1498 Op_Name = Name_Op_Divide)
1499 then
1500 -- Already checked above
1501
1502 null;
1503
e86a3a7e 1504 -- Operator may be defined in an extension of System
80c3be7a
AC		 1505
1506 elsif Present (System_Aux_Id)
1507 and then Scope (Opnd_Type) = System_Aux_Id
1508 then
1509 null;
1510
88b17d45 1511 else
be5a1b93
TQ		 1512 -- Could we use Wrong_Type here??? (this would require setting
1513 -- Etype (N) to the actual type found where Typ was expected).
1514
e86a3a7e 1515 Error_Msg_NE ("expect }", N, Typ);
88b17d45 1516 end if;
996ae0b0
RK		 1517 end if;
1518 end if;
1519
1520 Set_Chars (Op_Node, Op_Name);
fbf5a39b
AC		 1521
1522 if not Is_Private_Type (Etype (N)) then
1523 Set_Etype (Op_Node, Base_Type (Etype (N)));
1524 else
1525 Set_Etype (Op_Node, Etype (N));
1526 end if;
1527
2820d220
AC		 1528 -- If this is a call to a function that renames a predefined equality,
1529 -- the renaming declaration provides a type that must be used to
1530 -- resolve the operands. This must be done now because resolution of
1531 -- the equality node will not resolve any remaining ambiguity, and it
1532 -- assumes that the first operand is not overloaded.
1533
1534 if (Op_Name = Name_Op_Eq or else Op_Name = Name_Op_Ne)
1535 and then Ekind (Func) = E_Function
1536 and then Is_Overloaded (Act1)
1537 then
1538 Resolve (Act1, Base_Type (Etype (First_Formal (Func))));
1539 Resolve (Act2, Base_Type (Etype (First_Formal (Func))));
1540 end if;
1541
996ae0b0
RK		 1542 Set_Entity (Op_Node, Op_Id);
1543 Generate_Reference (Op_Id, N, ' ');
45fc7ddb
HK		 1544
1545 -- Do rewrite setting Comes_From_Source on the result if the original
1546 -- call came from source. Although it is not strictly the case that the
1547 -- operator as such comes from the source, logically it corresponds
1548 -- exactly to the function call in the source, so it should be marked
1549 -- this way (e.g. to make sure that validity checks work fine).
1550
1551 declare
1552 CS : constant Boolean := Comes_From_Source (N);
1553 begin
1554 Rewrite (N, Op_Node);
1555 Set_Comes_From_Source (N, CS);
1556 end;
fbf5a39b
AC		 1557
1558 -- If this is an arithmetic operator and the result type is private,
1559 -- the operands and the result must be wrapped in conversion to
1560 -- expose the underlying numeric type and expand the proper checks,
1561 -- e.g. on division.
1562
1563 if Is_Private_Type (Typ) then
1564 case Nkind (N) is
5cc9353d
RD		 1565 when N_Op_Add | N_Op_Subtract | N_Op_Multiply | N_Op_Divide |
1566 N_Op_Expon | N_Op_Mod | N_Op_Rem =>
fbf5a39b
AC		 1567 Resolve_Intrinsic_Operator (N, Typ);
1568
5cc9353d 1569 when N_Op_Plus | N_Op_Minus | N_Op_Abs =>
fbf5a39b
AC		 1570 Resolve_Intrinsic_Unary_Operator (N, Typ);
1571
1572 when others =>
1573 Resolve (N, Typ);
1574 end case;
1575 else
1576 Resolve (N, Typ);
1577 end if;
996ae0b0
RK		 1578 end Make_Call_Into_Operator;
1579
1580 -------------------
1581 -- Operator_Kind --
1582 -------------------
1583
1584 function Operator_Kind
1585 (Op_Name : Name_Id;
0ab80019 1586 Is_Binary : Boolean) return Node_Kind
996ae0b0
RK		 1587 is
1588 Kind : Node_Kind;
1589
1590 begin
b0186f71
AC		 1591 -- Use CASE statement or array???
1592
996ae0b0 1593 if Is_Binary then
aa5147f0
ES		 1594 if Op_Name = Name_Op_And then
1595 Kind := N_Op_And;
1596 elsif Op_Name = Name_Op_Or then
1597 Kind := N_Op_Or;
1598 elsif Op_Name = Name_Op_Xor then
1599 Kind := N_Op_Xor;
1600 elsif Op_Name = Name_Op_Eq then
1601 Kind := N_Op_Eq;
1602 elsif Op_Name = Name_Op_Ne then
1603 Kind := N_Op_Ne;
1604 elsif Op_Name = Name_Op_Lt then
1605 Kind := N_Op_Lt;
1606 elsif Op_Name = Name_Op_Le then
1607 Kind := N_Op_Le;
1608 elsif Op_Name = Name_Op_Gt then
1609 Kind := N_Op_Gt;
1610 elsif Op_Name = Name_Op_Ge then
1611 Kind := N_Op_Ge;
1612 elsif Op_Name = Name_Op_Add then
1613 Kind := N_Op_Add;
1614 elsif Op_Name = Name_Op_Subtract then
1615 Kind := N_Op_Subtract;
1616 elsif Op_Name = Name_Op_Concat then
1617 Kind := N_Op_Concat;
1618 elsif Op_Name = Name_Op_Multiply then
1619 Kind := N_Op_Multiply;
1620 elsif Op_Name = Name_Op_Divide then
1621 Kind := N_Op_Divide;
1622 elsif Op_Name = Name_Op_Mod then
1623 Kind := N_Op_Mod;
1624 elsif Op_Name = Name_Op_Rem then
1625 Kind := N_Op_Rem;
1626 elsif Op_Name = Name_Op_Expon then
1627 Kind := N_Op_Expon;
996ae0b0
RK		 1628 else
1629 raise Program_Error;
1630 end if;
1631
1632 -- Unary operators
1633
1634 else
aa5147f0
ES		 1635 if Op_Name = Name_Op_Add then
1636 Kind := N_Op_Plus;
1637 elsif Op_Name = Name_Op_Subtract then
1638 Kind := N_Op_Minus;
1639 elsif Op_Name = Name_Op_Abs then
1640 Kind := N_Op_Abs;
1641 elsif Op_Name = Name_Op_Not then
1642 Kind := N_Op_Not;
996ae0b0
RK		 1643 else
1644 raise Program_Error;
1645 end if;
1646 end if;
1647
1648 return Kind;
1649 end Operator_Kind;
1650
45fc7ddb
HK		 1651 ----------------------------
1652 -- Preanalyze_And_Resolve --
1653 ----------------------------
996ae0b0 1654
45fc7ddb 1655 procedure Preanalyze_And_Resolve (N : Node_Id; T : Entity_Id) is
996ae0b0
RK		 1656 Save_Full_Analysis : constant Boolean := Full_Analysis;
1657
1658 begin
1659 Full_Analysis := False;
1660 Expander_Mode_Save_And_Set (False);
1661
1662 -- We suppress all checks for this analysis, since the checks will
1663 -- be applied properly, and in the right location, when the default
1664 -- expression is reanalyzed and reexpanded later on.
1665
1666 Analyze_And_Resolve (N, T, Suppress => All_Checks);
1667
1668 Expander_Mode_Restore;
1669 Full_Analysis := Save_Full_Analysis;
45fc7ddb 1670 end Preanalyze_And_Resolve;
996ae0b0 1671
a77842bd 1672 -- Version without context type
996ae0b0 1673
45fc7ddb 1674 procedure Preanalyze_And_Resolve (N : Node_Id) is
996ae0b0
RK		 1675 Save_Full_Analysis : constant Boolean := Full_Analysis;
1676
1677 begin
1678 Full_Analysis := False;
1679 Expander_Mode_Save_And_Set (False);
1680
1681 Analyze (N);
1682 Resolve (N, Etype (N), Suppress => All_Checks);
1683
1684 Expander_Mode_Restore;
1685 Full_Analysis := Save_Full_Analysis;
45fc7ddb 1686 end Preanalyze_And_Resolve;
996ae0b0
RK		 1687
1688 ----------------------------------
1689 -- Replace_Actual_Discriminants --
1690 ----------------------------------
1691
1692 procedure Replace_Actual_Discriminants (N : Node_Id; Default : Node_Id) is
1693 Loc : constant Source_Ptr := Sloc (N);
1694 Tsk : Node_Id := Empty;
1695
1696 function Process_Discr (Nod : Node_Id) return Traverse_Result;
e0296583 1697 -- Comment needed???
996ae0b0
RK		 1698
1699 -------------------
1700 -- Process_Discr --
1701 -------------------
1702
1703 function Process_Discr (Nod : Node_Id) return Traverse_Result is
1704 Ent : Entity_Id;
1705
1706 begin
1707 if Nkind (Nod) = N_Identifier then
1708 Ent := Entity (Nod);
1709
1710 if Present (Ent)
1711 and then Ekind (Ent) = E_Discriminant
1712 then
1713 Rewrite (Nod,
1714 Make_Selected_Component (Loc,
1715 Prefix => New_Copy_Tree (Tsk, New_Sloc => Loc),
1716 Selector_Name => Make_Identifier (Loc, Chars (Ent))));
1717
1718 Set_Etype (Nod, Etype (Ent));
1719 end if;
1720
1721 end if;
1722
1723 return OK;
1724 end Process_Discr;
1725
1726 procedure Replace_Discrs is new Traverse_Proc (Process_Discr);
1727
1728 -- Start of processing for Replace_Actual_Discriminants
1729
1730 begin
11fa950b 1731 if not Full_Expander_Active then
996ae0b0
RK		 1732 return;
1733 end if;
1734
1735 if Nkind (Name (N)) = N_Selected_Component then
1736 Tsk := Prefix (Name (N));
1737
1738 elsif Nkind (Name (N)) = N_Indexed_Component then
1739 Tsk := Prefix (Prefix (Name (N)));
1740 end if;
1741
1742 if No (Tsk) then
1743 return;
1744 else
1745 Replace_Discrs (Default);
1746 end if;
1747 end Replace_Actual_Discriminants;
1748
1749 -------------
1750 -- Resolve --
1751 -------------
1752
1753 procedure Resolve (N : Node_Id; Typ : Entity_Id) is
dae2b8ea
HK		 1754 Ambiguous : Boolean := False;
1755 Ctx_Type : Entity_Id := Typ;
1756 Expr_Type : Entity_Id := Empty; -- prevent junk warning
1757 Err_Type : Entity_Id := Empty;
1758 Found : Boolean := False;
1759 From_Lib : Boolean;
996ae0b0 1760 I : Interp_Index;
dae2b8ea 1761 I1 : Interp_Index := 0; -- prevent junk warning
996ae0b0
RK		 1762 It : Interp;
1763 It1 : Interp;
996ae0b0 1764 Seen : Entity_Id := Empty; -- prevent junk warning
dae2b8ea
HK		 1765
1766 function Comes_From_Predefined_Lib_Unit (Nod : Node_Id) return Boolean;
1767 -- Determine whether a node comes from a predefined library unit or
1768 -- Standard.
996ae0b0
RK		 1769
1770 procedure Patch_Up_Value (N : Node_Id; Typ : Entity_Id);
1771 -- Try and fix up a literal so that it matches its expected type. New
1772 -- literals are manufactured if necessary to avoid cascaded errors.
1773
804670f1
AC		 1774 function Proper_Current_Scope return Entity_Id;
1775 -- Return the current scope. Skip loop scopes created for the purpose of
1776 -- quantified expression analysis since those do not appear in the tree.
1777
7415029d
AC		 1778 procedure Report_Ambiguous_Argument;
1779 -- Additional diagnostics when an ambiguous call has an ambiguous
1780 -- argument (typically a controlling actual).
1781
996ae0b0
RK		 1782 procedure Resolution_Failed;
1783 -- Called when attempt at resolving current expression fails
1784
dae2b8ea
HK		 1785 ------------------------------------
1786 -- Comes_From_Predefined_Lib_Unit --
1787 -------------------------------------
1788
1789 function Comes_From_Predefined_Lib_Unit (Nod : Node_Id) return Boolean is
1790 begin
1791 return
1792 Sloc (Nod) = Standard_Location
5cc9353d
RD		 1793 or else Is_Predefined_File_Name
1794 (Unit_File_Name (Get_Source_Unit (Sloc (Nod))));
dae2b8ea
HK		 1795 end Comes_From_Predefined_Lib_Unit;
1796
996ae0b0
RK		 1797 --------------------
1798 -- Patch_Up_Value --
1799 --------------------
1800
1801 procedure Patch_Up_Value (N : Node_Id; Typ : Entity_Id) is
1802 begin
e0296583 1803 if Nkind (N) = N_Integer_Literal and then Is_Real_Type (Typ) then
996ae0b0
RK		 1804 Rewrite (N,
1805 Make_Real_Literal (Sloc (N),
1806 Realval => UR_From_Uint (Intval (N))));
1807 Set_Etype (N, Universal_Real);
1808 Set_Is_Static_Expression (N);
1809
e0296583 1810 elsif Nkind (N) = N_Real_Literal and then Is_Integer_Type (Typ) then
996ae0b0
RK		 1811 Rewrite (N,
1812 Make_Integer_Literal (Sloc (N),
1813 Intval => UR_To_Uint (Realval (N))));
1814 Set_Etype (N, Universal_Integer);
1815 Set_Is_Static_Expression (N);
45fc7ddb 1816
996ae0b0 1817 elsif Nkind (N) = N_String_Literal
e0296583 1818 and then Is_Character_Type (Typ)
996ae0b0
RK		 1819 then
1820 Set_Character_Literal_Name (Char_Code (Character'Pos ('A')));
1821 Rewrite (N,
1822 Make_Character_Literal (Sloc (N),
1823 Chars => Name_Find,
82c80734
RD		 1824 Char_Literal_Value =>
1825 UI_From_Int (Character'Pos ('A'))));
996ae0b0
RK		 1826 Set_Etype (N, Any_Character);
1827 Set_Is_Static_Expression (N);
1828
e0296583 1829 elsif Nkind (N) /= N_String_Literal and then Is_String_Type (Typ) then
996ae0b0
RK		 1830 Rewrite (N,
1831 Make_String_Literal (Sloc (N),
1832 Strval => End_String));
1833
1834 elsif Nkind (N) = N_Range then
e0296583 1835 Patch_Up_Value (Low_Bound (N), Typ);
996ae0b0
RK		 1836 Patch_Up_Value (High_Bound (N), Typ);
1837 end if;
1838 end Patch_Up_Value;
1839
804670f1
AC		 1840 --------------------------
1841 -- Proper_Current_Scope --
1842 --------------------------
1843
1844 function Proper_Current_Scope return Entity_Id is
1845 S : Entity_Id := Current_Scope;
1846
1847 begin
1848 while Present (S) loop
1849
1850 -- Skip a loop scope created for quantified expression analysis
1851
1852 if Ekind (S) = E_Loop
1853 and then Nkind (Parent (S)) = N_Quantified_Expression
1854 then
1855 S := Scope (S);
1856 else
1857 exit;
1858 end if;
1859 end loop;
1860
1861 return S;
1862 end Proper_Current_Scope;
1863
7415029d
AC		 1864 -------------------------------
1865 -- Report_Ambiguous_Argument --
1866 -------------------------------
1867
1868 procedure Report_Ambiguous_Argument is
1869 Arg : constant Node_Id := First (Parameter_Associations (N));
1870 I : Interp_Index;
1871 It : Interp;
1872
1873 begin
1874 if Nkind (Arg) = N_Function_Call
1875 and then Is_Entity_Name (Name (Arg))
1876 and then Is_Overloaded (Name (Arg))
1877 then
ed2233dc 1878 Error_Msg_NE ("ambiguous call to&", Arg, Name (Arg));
7415029d 1879
e0296583 1880 -- Could use comments on what is going on here???
bfc07071 1881
7415029d
AC		 1882 Get_First_Interp (Name (Arg), I, It);
1883 while Present (It.Nam) loop
1884 Error_Msg_Sloc := Sloc (It.Nam);
1885
1886 if Nkind (Parent (It.Nam)) = N_Full_Type_Declaration then
ed2233dc 1887 Error_Msg_N ("interpretation (inherited) #!", Arg);
7415029d 1888 else
ed2233dc 1889 Error_Msg_N ("interpretation #!", Arg);
7415029d
AC		 1890 end if;
1891
1892 Get_Next_Interp (I, It);
1893 end loop;
1894 end if;
1895 end Report_Ambiguous_Argument;
1896
996ae0b0
RK		 1897 -----------------------
1898 -- Resolution_Failed --
1899 -----------------------
1900
1901 procedure Resolution_Failed is
1902 begin
1903 Patch_Up_Value (N, Typ);
1904 Set_Etype (N, Typ);
1905 Debug_A_Exit ("resolving ", N, " (done, resolution failed)");
1906 Set_Is_Overloaded (N, False);
1907
1908 -- The caller will return without calling the expander, so we need
1909 -- to set the analyzed flag. Note that it is fine to set Analyzed
1910 -- to True even if we are in the middle of a shallow analysis,
1911 -- (see the spec of sem for more details) since this is an error
1912 -- situation anyway, and there is no point in repeating the
1913 -- analysis later (indeed it won't work to repeat it later, since
1914 -- we haven't got a clear resolution of which entity is being
1915 -- referenced.)
1916
1917 Set_Analyzed (N, True);
1918 return;
1919 end Resolution_Failed;
1920
1921 -- Start of processing for Resolve
1922
1923 begin
5c736541
RD		 1924 if N = Error then
1925 return;
1926 end if;
1927
e0296583
AC		 1928 -- Access attribute on remote subprogram cannot be used for a non-remote
1929 -- access-to-subprogram type.
996ae0b0
RK		 1930
1931 if Nkind (N) = N_Attribute_Reference
19fb051c
AC		 1932 and then (Attribute_Name (N) = Name_Access or else
1933 Attribute_Name (N) = Name_Unrestricted_Access or else
1934 Attribute_Name (N) = Name_Unchecked_Access)
996ae0b0
RK		 1935 and then Comes_From_Source (N)
1936 and then Is_Entity_Name (Prefix (N))
1937 and then Is_Subprogram (Entity (Prefix (N)))
1938 and then Is_Remote_Call_Interface (Entity (Prefix (N)))
1939 and then not Is_Remote_Access_To_Subprogram_Type (Typ)
1940 then
1941 Error_Msg_N
1942 ("prefix must statically denote a non-remote subprogram", N);
1943 end if;
1944
dae2b8ea
HK		 1945 From_Lib := Comes_From_Predefined_Lib_Unit (N);
1946
996ae0b0
RK		 1947 -- If the context is a Remote_Access_To_Subprogram, access attributes
1948 -- must be resolved with the corresponding fat pointer. There is no need
1949 -- to check for the attribute name since the return type of an
1950 -- attribute is never a remote type.
1951
1952 if Nkind (N) = N_Attribute_Reference
1953 and then Comes_From_Source (N)
19fb051c 1954 and then (Is_Remote_Call_Interface (Typ) or else Is_Remote_Types (Typ))
996ae0b0
RK		 1955 then
1956 declare
1957 Attr : constant Attribute_Id :=
1958 Get_Attribute_Id (Attribute_Name (N));
1959 Pref : constant Node_Id := Prefix (N);
1960 Decl : Node_Id;
1961 Spec : Node_Id;
1962 Is_Remote : Boolean := True;
1963
1964 begin
a77842bd 1965 -- Check that Typ is a remote access-to-subprogram type
996ae0b0 1966
a77842bd 1967 if Is_Remote_Access_To_Subprogram_Type (Typ) then
955871d3 1968
996ae0b0
RK		 1969 -- Prefix (N) must statically denote a remote subprogram
1970 -- declared in a package specification.
1971
799d0e05
AC		 1972 if Attr = Attribute_Access or else
1973 Attr = Attribute_Unchecked_Access or else
1974 Attr = Attribute_Unrestricted_Access
1975 then
996ae0b0
RK		 1976 Decl := Unit_Declaration_Node (Entity (Pref));
1977
1978 if Nkind (Decl) = N_Subprogram_Body then
1979 Spec := Corresponding_Spec (Decl);
1980
1981 if not No (Spec) then
1982 Decl := Unit_Declaration_Node (Spec);
1983 end if;
1984 end if;
1985
1986 Spec := Parent (Decl);
1987
1988 if not Is_Entity_Name (Prefix (N))
1989 or else Nkind (Spec) /= N_Package_Specification
1990 or else
1991 not Is_Remote_Call_Interface (Defining_Entity (Spec))
1992 then
1993 Is_Remote := False;
1994 Error_Msg_N
1995 ("prefix must statically denote a remote subprogram ",
1996 N);
1997 end if;
996ae0b0 1998
799d0e05
AC		 1999 -- If we are generating code in distributed mode, perform
2000 -- semantic checks against corresponding remote entities.
fbf5a39b 2001
799d0e05
AC		 2002 if Full_Expander_Active
2003 and then Get_PCS_Name /= Name_No_DSA
2004 then
2005 Check_Subtype_Conformant
2006 (New_Id => Entity (Prefix (N)),
2007 Old_Id => Designated_Type
2008 (Corresponding_Remote_Type (Typ)),
2009 Err_Loc => N);
2010
2011 if Is_Remote then
2012 Process_Remote_AST_Attribute (N, Typ);
2013 end if;
996ae0b0
RK		 2014 end if;
2015 end if;
2016 end if;
2017 end;
2018 end if;
2019
2020 Debug_A_Entry ("resolving ", N);
fe58fea7 2021
ee1a7572
AC		 2022 if Debug_Flag_V then
2023 Write_Overloads (N);
2024 end if;
996ae0b0 2025
07fc65c4
GB		 2026 if Comes_From_Source (N) then
2027 if Is_Fixed_Point_Type (Typ) then
2028 Check_Restriction (No_Fixed_Point, N);
996ae0b0 2029
07fc65c4
GB		 2030 elsif Is_Floating_Point_Type (Typ)
2031 and then Typ /= Universal_Real
2032 and then Typ /= Any_Real
2033 then
2034 Check_Restriction (No_Floating_Point, N);
2035 end if;
996ae0b0
RK		 2036 end if;
2037
2038 -- Return if already analyzed
2039
2040 if Analyzed (N) then
2041 Debug_A_Exit ("resolving ", N, " (done, already analyzed)");
dec6faf1 2042 Analyze_Dimension (N);
996ae0b0
RK		 2043 return;
2044
2045 -- Return if type = Any_Type (previous error encountered)
2046
2047 elsif Etype (N) = Any_Type then
2048 Debug_A_Exit ("resolving ", N, " (done, Etype = Any_Type)");
2049 return;
2050 end if;
2051
2052 Check_Parameterless_Call (N);
2053
2054 -- If not overloaded, then we know the type, and all that needs doing
2055 -- is to check that this type is compatible with the context.
2056
2057 if not Is_Overloaded (N) then
2058 Found := Covers (Typ, Etype (N));
2059 Expr_Type := Etype (N);
2060
2061 -- In the overloaded case, we must select the interpretation that
2062 -- is compatible with the context (i.e. the type passed to Resolve)
2063
2064 else
996ae0b0
RK		 2065 -- Loop through possible interpretations
2066
1420b484 2067 Get_First_Interp (N, I, It);
996ae0b0
RK		 2068 Interp_Loop : while Present (It.Typ) loop
2069
ee1a7572
AC		 2070 if Debug_Flag_V then
2071 Write_Str ("Interp: ");
2072 Write_Interp (It);
2073 end if;
2074
996ae0b0 2075 -- We are only interested in interpretations that are compatible
aa5147f0 2076 -- with the expected type, any other interpretations are ignored.
996ae0b0 2077
fbf5a39b
AC		 2078 if not Covers (Typ, It.Typ) then
2079 if Debug_Flag_V then
2080 Write_Str (" interpretation incompatible with context");
2081 Write_Eol;
2082 end if;
996ae0b0 2083
fbf5a39b 2084 else
aa5147f0
ES		 2085 -- Skip the current interpretation if it is disabled by an
2086 -- abstract operator. This action is performed only when the
2087 -- type against which we are resolving is the same as the
2088 -- type of the interpretation.
2089
0791fbe9 2090 if Ada_Version >= Ada_2005
aa5147f0
ES		 2091 and then It.Typ = Typ
2092 and then Typ /= Universal_Integer
2093 and then Typ /= Universal_Real
2094 and then Present (It.Abstract_Op)
2095 then
ee1a7572
AC		 2096 if Debug_Flag_V then
2097 Write_Line ("Skip.");
2098 end if;
2099
aa5147f0
ES		 2100 goto Continue;
2101 end if;
2102
996ae0b0
RK		 2103 -- First matching interpretation
2104
2105 if not Found then
2106 Found := True;
2107 I1 := I;
2108 Seen := It.Nam;
2109 Expr_Type := It.Typ;
2110
fbf5a39b 2111 -- Matching interpretation that is not the first, maybe an
996ae0b0
RK		 2112 -- error, but there are some cases where preference rules are
2113 -- used to choose between the two possibilities. These and
2114 -- some more obscure cases are handled in Disambiguate.
2115
2116 else
dae2b8ea
HK		 2117 -- If the current statement is part of a predefined library
2118 -- unit, then all interpretations which come from user level
2119 -- packages should not be considered.
2120
2121 if From_Lib
2122 and then not Comes_From_Predefined_Lib_Unit (It.Nam)
2123 then
2124 goto Continue;
2125 end if;
2126
996ae0b0
RK		 2127 Error_Msg_Sloc := Sloc (Seen);
2128 It1 := Disambiguate (N, I1, I, Typ);
2129
fbf5a39b
AC		 2130 -- Disambiguation has succeeded. Skip the remaining
2131 -- interpretations.
996ae0b0 2132
fbf5a39b
AC		 2133 if It1 /= No_Interp then
2134 Seen := It1.Nam;
2135 Expr_Type := It1.Typ;
2136
2137 while Present (It.Typ) loop
2138 Get_Next_Interp (I, It);
2139 end loop;
2140
2141 else
996ae0b0
RK		 2142 -- Before we issue an ambiguity complaint, check for
2143 -- the case of a subprogram call where at least one
2144 -- of the arguments is Any_Type, and if so, suppress
2145 -- the message, since it is a cascaded error.
2146
d3b00ce3 2147 if Nkind (N) in N_Subprogram_Call then
996ae0b0 2148 declare
1420b484 2149 A : Node_Id;
996ae0b0
RK		 2150 E : Node_Id;
2151
2152 begin
1420b484 2153 A := First_Actual (N);
996ae0b0
RK		 2154 while Present (A) loop
2155 E := A;
2156
2157 if Nkind (E) = N_Parameter_Association then
2158 E := Explicit_Actual_Parameter (E);
2159 end if;
2160
2161 if Etype (E) = Any_Type then
2162 if Debug_Flag_V then
2163 Write_Str ("Any_Type in call");
2164 Write_Eol;
2165 end if;
2166
2167 exit Interp_Loop;
2168 end if;
2169
2170 Next_Actual (A);
2171 end loop;
2172 end;
2173
aa5147f0 2174 elsif Nkind (N) in N_Binary_Op
996ae0b0
RK		 2175 and then (Etype (Left_Opnd (N)) = Any_Type
2176 or else Etype (Right_Opnd (N)) = Any_Type)
2177 then
2178 exit Interp_Loop;
2179
2180 elsif Nkind (N) in N_Unary_Op
2181 and then Etype (Right_Opnd (N)) = Any_Type
2182 then
2183 exit Interp_Loop;
2184 end if;
2185
2186 -- Not that special case, so issue message using the
2187 -- flag Ambiguous to control printing of the header
2188 -- message only at the start of an ambiguous set.
2189
2190 if not Ambiguous then
aa180613
RD		 2191 if Nkind (N) = N_Function_Call
2192 and then Nkind (Name (N)) = N_Explicit_Dereference
2193 then
ed2233dc 2194 Error_Msg_N
aa180613
RD		 2195 ("ambiguous expression "
2196 & "(cannot resolve indirect call)!", N);
2197 else
483c78cb 2198 Error_Msg_NE -- CODEFIX
aa180613
RD		 2199 ("ambiguous expression (cannot resolve&)!",
2200 N, It.Nam);
2201 end if;
fbf5a39b 2202
996ae0b0 2203 Ambiguous := True;
0669bebe
GB		 2204
2205 if Nkind (Parent (Seen)) = N_Full_Type_Declaration then
ed2233dc 2206 Error_Msg_N
0669bebe
GB		 2207 ("\\possible interpretation (inherited)#!", N);
2208 else
4e7a4f6e
AC		 2209 Error_Msg_N -- CODEFIX
2210 ("\\possible interpretation#!", N);
0669bebe 2211 end if;
7415029d 2212
d3b00ce3 2213 if Nkind (N) in N_Subprogram_Call
7415029d
AC		 2214 and then Present (Parameter_Associations (N))
2215 then
2216 Report_Ambiguous_Argument;
2217 end if;
996ae0b0
RK		 2218 end if;
2219
2220 Error_Msg_Sloc := Sloc (It.Nam);
996ae0b0 2221
fbf5a39b 2222 -- By default, the error message refers to the candidate
0669bebe
GB		 2223 -- interpretation. But if it is a predefined operator, it
2224 -- is implicitly declared at the declaration of the type
2225 -- of the operand. Recover the sloc of that declaration
2226 -- for the error message.
fbf5a39b
AC		 2227
2228 if Nkind (N) in N_Op
2229 and then Scope (It.Nam) = Standard_Standard
2230 and then not Is_Overloaded (Right_Opnd (N))
0669bebe
GB		 2231 and then Scope (Base_Type (Etype (Right_Opnd (N)))) /=
2232 Standard_Standard
fbf5a39b
AC		 2233 then
2234 Err_Type := First_Subtype (Etype (Right_Opnd (N)));
2235
2236 if Comes_From_Source (Err_Type)
2237 and then Present (Parent (Err_Type))
2238 then
2239 Error_Msg_Sloc := Sloc (Parent (Err_Type));
2240 end if;
2241
2242 elsif Nkind (N) in N_Binary_Op
2243 and then Scope (It.Nam) = Standard_Standard
2244 and then not Is_Overloaded (Left_Opnd (N))
0669bebe
GB		 2245 and then Scope (Base_Type (Etype (Left_Opnd (N)))) /=
2246 Standard_Standard
fbf5a39b
AC		 2247 then
2248 Err_Type := First_Subtype (Etype (Left_Opnd (N)));
2249
2250 if Comes_From_Source (Err_Type)
2251 and then Present (Parent (Err_Type))
2252 then
2253 Error_Msg_Sloc := Sloc (Parent (Err_Type));
2254 end if;
aa180613
RD		 2255
2256 -- If this is an indirect call, use the subprogram_type
5cc9353d
RD		 2257 -- in the message, to have a meaningful location. Also
2258 -- indicate if this is an inherited operation, created
2259 -- by a type declaration.
aa180613
RD		 2260
2261 elsif Nkind (N) = N_Function_Call
2262 and then Nkind (Name (N)) = N_Explicit_Dereference
2263 and then Is_Type (It.Nam)
2264 then
2265 Err_Type := It.Nam;
2266 Error_Msg_Sloc :=
2267 Sloc (Associated_Node_For_Itype (Err_Type));
fbf5a39b
AC		 2268 else
2269 Err_Type := Empty;
2270 end if;
2271
2272 if Nkind (N) in N_Op
2273 and then Scope (It.Nam) = Standard_Standard
2274 and then Present (Err_Type)
2275 then
aa5147f0
ES		 2276 -- Special-case the message for universal_fixed
2277 -- operators, which are not declared with the type
2278 -- of the operand, but appear forever in Standard.
2279
2280 if It.Typ = Universal_Fixed
2281 and then Scope (It.Nam) = Standard_Standard
2282 then
ed2233dc 2283 Error_Msg_N
aa5147f0
ES		 2284 ("\\possible interpretation as " &
2285 "universal_fixed operation " &
2286 "(RM 4.5.5 (19))", N);
2287 else
ed2233dc 2288 Error_Msg_N
aa5147f0
ES		 2289 ("\\possible interpretation (predefined)#!", N);
2290 end if;
aa180613
RD		 2291
2292 elsif
2293 Nkind (Parent (It.Nam)) = N_Full_Type_Declaration
2294 then
ed2233dc 2295 Error_Msg_N
aa180613 2296 ("\\possible interpretation (inherited)#!", N);
fbf5a39b 2297 else
4e7a4f6e
AC		 2298 Error_Msg_N -- CODEFIX
2299 ("\\possible interpretation#!", N);
fbf5a39b 2300 end if;
996ae0b0 2301
996ae0b0
RK		 2302 end if;
2303 end if;
2304
0669bebe
GB		 2305 -- We have a matching interpretation, Expr_Type is the type
2306 -- from this interpretation, and Seen is the entity.
996ae0b0 2307
0669bebe
GB		 2308 -- For an operator, just set the entity name. The type will be
2309 -- set by the specific operator resolution routine.
996ae0b0
RK		 2310
2311 if Nkind (N) in N_Op then
2312 Set_Entity (N, Seen);
2313 Generate_Reference (Seen, N);
2314
19d846a0
RD		 2315 elsif Nkind (N) = N_Case_Expression then
2316 Set_Etype (N, Expr_Type);
2317
996ae0b0
RK		 2318 elsif Nkind (N) = N_Character_Literal then
2319 Set_Etype (N, Expr_Type);
2320
e0ba1bfd
ES		 2321 elsif Nkind (N) = N_Conditional_Expression then
2322 Set_Etype (N, Expr_Type);
2323
dedac3eb
RD		 2324 -- AI05-0139-2: Expression is overloaded because type has
2325 -- implicit dereference. If type matches context, no implicit
2326 -- dereference is involved.
44a10091
AC		 2327
2328 elsif Has_Implicit_Dereference (Expr_Type) then
2329 Set_Etype (N, Expr_Type);
2330 Set_Is_Overloaded (N, False);
2331 exit Interp_Loop;
2332
2333 elsif Is_Overloaded (N)
2334 and then Present (It.Nam)
2335 and then Ekind (It.Nam) = E_Discriminant
2336 and then Has_Implicit_Dereference (It.Nam)
2337 then
2338 Build_Explicit_Dereference (N, It.Nam);
2339
996ae0b0 2340 -- For an explicit dereference, attribute reference, range,
0669bebe
GB		 2341 -- short-circuit form (which is not an operator node), or call
2342 -- with a name that is an explicit dereference, there is
2343 -- nothing to be done at this point.
996ae0b0 2344
45fc7ddb
HK		 2345 elsif Nkind_In (N, N_Explicit_Dereference,
2346 N_Attribute_Reference,
2347 N_And_Then,
2348 N_Indexed_Component,
2349 N_Or_Else,
2350 N_Range,
2351 N_Selected_Component,
2352 N_Slice)
996ae0b0
RK		 2353 or else Nkind (Name (N)) = N_Explicit_Dereference
2354 then
2355 null;
2356
0669bebe 2357 -- For procedure or function calls, set the type of the name,
4519314c 2358 -- and also the entity pointer for the prefix.
996ae0b0 2359
d3b00ce3 2360 elsif Nkind (N) in N_Subprogram_Call
a3f2babd 2361 and then Is_Entity_Name (Name (N))
996ae0b0
RK		 2362 then
2363 Set_Etype (Name (N), Expr_Type);
2364 Set_Entity (Name (N), Seen);
2365 Generate_Reference (Seen, Name (N));
2366
2367 elsif Nkind (N) = N_Function_Call
2368 and then Nkind (Name (N)) = N_Selected_Component
2369 then
2370 Set_Etype (Name (N), Expr_Type);
2371 Set_Entity (Selector_Name (Name (N)), Seen);
2372 Generate_Reference (Seen, Selector_Name (Name (N)));
2373
2374 -- For all other cases, just set the type of the Name
2375
2376 else
2377 Set_Etype (Name (N), Expr_Type);
2378 end if;
2379
996ae0b0
RK		 2380 end if;
2381
aa5147f0
ES		 2382 <<Continue>>
2383
996ae0b0
RK		 2384 -- Move to next interpretation
2385
c8ef728f 2386 exit Interp_Loop when No (It.Typ);
996ae0b0
RK		 2387
2388 Get_Next_Interp (I, It);
2389 end loop Interp_Loop;
2390 end if;
2391
2392 -- At this stage Found indicates whether or not an acceptable
4519314c
AC		 2393 -- interpretation exists. If not, then we have an error, except that if
2394 -- the context is Any_Type as a result of some other error, then we
2395 -- suppress the error report.
996ae0b0
RK		 2396
2397 if not Found then
2398 if Typ /= Any_Type then
2399
0669bebe
GB		 2400 -- If type we are looking for is Void, then this is the procedure
2401 -- call case, and the error is simply that what we gave is not a
2402 -- procedure name (we think of procedure calls as expressions with
2403 -- types internally, but the user doesn't think of them this way!)
996ae0b0
RK		 2404
2405 if Typ = Standard_Void_Type then
91b1417d
AC		 2406
2407 -- Special case message if function used as a procedure
2408
2409 if Nkind (N) = N_Procedure_Call_Statement
2410 and then Is_Entity_Name (Name (N))
2411 and then Ekind (Entity (Name (N))) = E_Function
2412 then
2413 Error_Msg_NE
2414 ("cannot use function & in a procedure call",
2415 Name (N), Entity (Name (N)));
2416
0669bebe
GB		 2417 -- Otherwise give general message (not clear what cases this
2418 -- covers, but no harm in providing for them!)
91b1417d
AC		 2419
2420 else
2421 Error_Msg_N ("expect procedure name in procedure call", N);
2422 end if;
2423
996ae0b0
RK		 2424 Found := True;
2425
2426 -- Otherwise we do have a subexpression with the wrong type
2427
0669bebe
GB		 2428 -- Check for the case of an allocator which uses an access type
2429 -- instead of the designated type. This is a common error and we
2430 -- specialize the message, posting an error on the operand of the
2431 -- allocator, complaining that we expected the designated type of
2432 -- the allocator.
996ae0b0
RK		 2433
2434 elsif Nkind (N) = N_Allocator
2435 and then Ekind (Typ) in Access_Kind
2436 and then Ekind (Etype (N)) in Access_Kind
2437 and then Designated_Type (Etype (N)) = Typ
2438 then
2439 Wrong_Type (Expression (N), Designated_Type (Typ));
2440 Found := True;
2441
0669bebe
GB		 2442 -- Check for view mismatch on Null in instances, for which the
2443 -- view-swapping mechanism has no identifier.
17be0cdf
ES		 2444
2445 elsif (In_Instance or else In_Inlined_Body)
2446 and then (Nkind (N) = N_Null)
2447 and then Is_Private_Type (Typ)
2448 and then Is_Access_Type (Full_View (Typ))
2449 then
2450 Resolve (N, Full_View (Typ));
2451 Set_Etype (N, Typ);
2452 return;
2453
aa180613
RD		 2454 -- Check for an aggregate. Sometimes we can get bogus aggregates
2455 -- from misuse of parentheses, and we are about to complain about
2456 -- the aggregate without even looking inside it.
996ae0b0 2457
aa180613
RD		 2458 -- Instead, if we have an aggregate of type Any_Composite, then
2459 -- analyze and resolve the component fields, and then only issue
2460 -- another message if we get no errors doing this (otherwise
2461 -- assume that the errors in the aggregate caused the problem).
996ae0b0
RK		 2462
2463 elsif Nkind (N) = N_Aggregate
2464 and then Etype (N) = Any_Composite
2465 then
996ae0b0
RK		 2466 -- Disable expansion in any case. If there is a type mismatch
2467 -- it may be fatal to try to expand the aggregate. The flag
2468 -- would otherwise be set to false when the error is posted.
2469
2470 Expander_Active := False;
2471
2472 declare
2473 procedure Check_Aggr (Aggr : Node_Id);
aa180613
RD		 2474 -- Check one aggregate, and set Found to True if we have a
2475 -- definite error in any of its elements
996ae0b0
RK		 2476
2477 procedure Check_Elmt (Aelmt : Node_Id);
aa180613
RD		 2478 -- Check one element of aggregate and set Found to True if
2479 -- we definitely have an error in the element.
2480
2481 ----------------
2482 -- Check_Aggr --
2483 ----------------
996ae0b0
RK		 2484
2485 procedure Check_Aggr (Aggr : Node_Id) is
2486 Elmt : Node_Id;
2487
2488 begin
2489 if Present (Expressions (Aggr)) then
2490 Elmt := First (Expressions (Aggr));
2491 while Present (Elmt) loop
2492 Check_Elmt (Elmt);
2493 Next (Elmt);
2494 end loop;
2495 end if;
2496
2497 if Present (Component_Associations (Aggr)) then
2498 Elmt := First (Component_Associations (Aggr));
2499 while Present (Elmt) loop
aa180613 2500
0669bebe
GB		 2501 -- If this is a default-initialized component, then
2502 -- there is nothing to check. The box will be
2503 -- replaced by the appropriate call during late
2504 -- expansion.
aa180613
RD		 2505
2506 if not Box_Present (Elmt) then
2507 Check_Elmt (Expression (Elmt));
2508 end if;
2509
996ae0b0
RK		 2510 Next (Elmt);
2511 end loop;
2512 end if;
2513 end Check_Aggr;
2514
fbf5a39b
AC		 2515 ----------------
2516 -- Check_Elmt --
2517 ----------------
2518
996ae0b0
RK		 2519 procedure Check_Elmt (Aelmt : Node_Id) is
2520 begin
2521 -- If we have a nested aggregate, go inside it (to
5cc9353d
RD		 2522 -- attempt a naked analyze-resolve of the aggregate can
2523 -- cause undesirable cascaded errors). Do not resolve
2524 -- expression if it needs a type from context, as for
2525 -- integer * fixed expression.
996ae0b0
RK		 2526
2527 if Nkind (Aelmt) = N_Aggregate then
2528 Check_Aggr (Aelmt);
2529
2530 else
2531 Analyze (Aelmt);
2532
2533 if not Is_Overloaded (Aelmt)
2534 and then Etype (Aelmt) /= Any_Fixed
2535 then
fbf5a39b 2536 Resolve (Aelmt);
996ae0b0
RK		 2537 end if;
2538
2539 if Etype (Aelmt) = Any_Type then
2540 Found := True;
2541 end if;
2542 end if;
2543 end Check_Elmt;
2544
2545 begin
2546 Check_Aggr (N);
2547 end;
2548 end if;
2549
5cc9353d
RD		 2550 -- If an error message was issued already, Found got reset to
2551 -- True, so if it is still False, issue standard Wrong_Type msg.
996ae0b0
RK		 2552
2553 if not Found then
2554 if Is_Overloaded (N)
2555 and then Nkind (N) = N_Function_Call
2556 then
65356e64
AC		 2557 declare
2558 Subp_Name : Node_Id;
2559 begin
2560 if Is_Entity_Name (Name (N)) then
2561 Subp_Name := Name (N);
2562
2563 elsif Nkind (Name (N)) = N_Selected_Component then
2564
a77842bd 2565 -- Protected operation: retrieve operation name
65356e64
AC		 2566
2567 Subp_Name := Selector_Name (Name (N));
19fb051c 2568
65356e64
AC		 2569 else
2570 raise Program_Error;
2571 end if;
2572
2573 Error_Msg_Node_2 := Typ;
2574 Error_Msg_NE ("no visible interpretation of&" &
2575 " matches expected type&", N, Subp_Name);
2576 end;
996ae0b0
RK		 2577
2578 if All_Errors_Mode then
2579 declare
2580 Index : Interp_Index;
2581 It : Interp;
2582
2583 begin
aa180613 2584 Error_Msg_N ("\\possible interpretations:", N);
996ae0b0 2585
1420b484 2586 Get_First_Interp (Name (N), Index, It);
996ae0b0 2587 while Present (It.Nam) loop
ea985d95 2588 Error_Msg_Sloc := Sloc (It.Nam);
aa5147f0
ES		 2589 Error_Msg_Node_2 := It.Nam;
2590 Error_Msg_NE
2591 ("\\ type& for & declared#", N, It.Typ);
996ae0b0
RK		 2592 Get_Next_Interp (Index, It);
2593 end loop;
2594 end;
aa5147f0 2595
996ae0b0
RK		 2596 else
2597 Error_Msg_N ("\use -gnatf for details", N);
2598 end if;
19fb051c 2599
996ae0b0
RK		 2600 else
2601 Wrong_Type (N, Typ);
2602 end if;
2603 end if;
2604 end if;
2605
2606 Resolution_Failed;
2607 return;
2608
2609 -- Test if we have more than one interpretation for the context
2610
2611 elsif Ambiguous then
2612 Resolution_Failed;
2613 return;
2614
fe58fea7
AC		 2615 -- Only one intepretation
2616
996ae0b0 2617 else
ee1a7572
AC		 2618 -- In Ada 2005, if we have something like "X : T := 2 + 2;", where
2619 -- the "+" on T is abstract, and the operands are of universal type,
2620 -- the above code will have (incorrectly) resolved the "+" to the
fe58fea7
AC		 2621 -- universal one in Standard. Therefore check for this case and give
2622 -- an error. We can't do this earlier, because it would cause legal
2623 -- cases to get errors (when some other type has an abstract "+").
ee1a7572 2624
36504e5f
AC		 2625 if Ada_Version >= Ada_2005
2626 and then Nkind (N) in N_Op
2627 and then Is_Overloaded (N)
2628 and then Is_Universal_Numeric_Type (Etype (Entity (N)))
ee1a7572
AC		 2629 then
2630 Get_First_Interp (N, I, It);
2631 while Present (It.Typ) loop
2632 if Present (It.Abstract_Op) and then
2633 Etype (It.Abstract_Op) = Typ
2634 then
2635 Error_Msg_NE
2636 ("cannot call abstract subprogram &!", N, It.Abstract_Op);
2637 return;
2638 end if;
2639
2640 Get_Next_Interp (I, It);
2641 end loop;
2642 end if;
2643
2644 -- Here we have an acceptable interpretation for the context
2645
996ae0b0
RK		 2646 -- Propagate type information and normalize tree for various
2647 -- predefined operations. If the context only imposes a class of
2648 -- types, rather than a specific type, propagate the actual type
2649 -- downward.
2650
19fb051c
AC		 2651 if Typ = Any_Integer or else
2652 Typ = Any_Boolean or else
2653 Typ = Any_Modular or else
2654 Typ = Any_Real or else
2655 Typ = Any_Discrete
996ae0b0
RK		 2656 then
2657 Ctx_Type := Expr_Type;
2658
5cc9353d
RD		 2659 -- Any_Fixed is legal in a real context only if a specific fixed-
2660 -- point type is imposed. If Norman Cohen can be confused by this,
2661 -- it deserves a separate message.
996ae0b0
RK		 2662
2663 if Typ = Any_Real
2664 and then Expr_Type = Any_Fixed
2665 then
758c442c 2666 Error_Msg_N ("illegal context for mixed mode operation", N);
996ae0b0
RK		 2667 Set_Etype (N, Universal_Real);
2668 Ctx_Type := Universal_Real;
2669 end if;
2670 end if;
2671
f3d57416 2672 -- A user-defined operator is transformed into a function call at
0ab80019
AC		 2673 -- this point, so that further processing knows that operators are
2674 -- really operators (i.e. are predefined operators). User-defined
2675 -- operators that are intrinsic are just renamings of the predefined
2676 -- ones, and need not be turned into calls either, but if they rename
2677 -- a different operator, we must transform the node accordingly.
2678 -- Instantiations of Unchecked_Conversion are intrinsic but are
2679 -- treated as functions, even if given an operator designator.
2680
2681 if Nkind (N) in N_Op
2682 and then Present (Entity (N))
2683 and then Ekind (Entity (N)) /= E_Operator
2684 then
2685
2686 if not Is_Predefined_Op (Entity (N)) then
2687 Rewrite_Operator_As_Call (N, Entity (N));
2688
615cbd95
AC		 2689 elsif Present (Alias (Entity (N)))
2690 and then
45fc7ddb
HK		 2691 Nkind (Parent (Parent (Entity (N)))) =
2692 N_Subprogram_Renaming_Declaration
615cbd95 2693 then
0ab80019
AC		 2694 Rewrite_Renamed_Operator (N, Alias (Entity (N)), Typ);
2695
2696 -- If the node is rewritten, it will be fully resolved in
2697 -- Rewrite_Renamed_Operator.
2698
2699 if Analyzed (N) then
2700 return;
2701 end if;
2702 end if;
2703 end if;
2704
996ae0b0
RK		 2705 case N_Subexpr'(Nkind (N)) is
2706
2707 when N_Aggregate => Resolve_Aggregate (N, Ctx_Type);
2708
2709 when N_Allocator => Resolve_Allocator (N, Ctx_Type);
2710
514d0fc5 2711 when N_Short_Circuit
996ae0b0
RK		 2712 => Resolve_Short_Circuit (N, Ctx_Type);
2713
2714 when N_Attribute_Reference
2715 => Resolve_Attribute (N, Ctx_Type);
2716
19d846a0
RD		 2717 when N_Case_Expression
2718 => Resolve_Case_Expression (N, Ctx_Type);
2719
996ae0b0
RK		 2720 when N_Character_Literal
2721 => Resolve_Character_Literal (N, Ctx_Type);
2722
2723 when N_Conditional_Expression
2724 => Resolve_Conditional_Expression (N, Ctx_Type);
2725
2726 when N_Expanded_Name
2727 => Resolve_Entity_Name (N, Ctx_Type);
2728
996ae0b0
RK		 2729 when N_Explicit_Dereference
2730 => Resolve_Explicit_Dereference (N, Ctx_Type);
2731
955871d3
AC		 2732 when N_Expression_With_Actions
2733 => Resolve_Expression_With_Actions (N, Ctx_Type);
2734
2735 when N_Extension_Aggregate
2736 => Resolve_Extension_Aggregate (N, Ctx_Type);
2737
996ae0b0
RK		 2738 when N_Function_Call
2739 => Resolve_Call (N, Ctx_Type);
2740
2741 when N_Identifier
2742 => Resolve_Entity_Name (N, Ctx_Type);
2743
996ae0b0
RK		 2744 when N_Indexed_Component
2745 => Resolve_Indexed_Component (N, Ctx_Type);
2746
2747 when N_Integer_Literal
2748 => Resolve_Integer_Literal (N, Ctx_Type);
2749
0669bebe
GB		 2750 when N_Membership_Test
2751 => Resolve_Membership_Op (N, Ctx_Type);
2752
996ae0b0
RK		 2753 when N_Null => Resolve_Null (N, Ctx_Type);
2754
2755 when N_Op_And | N_Op_Or | N_Op_Xor
2756 => Resolve_Logical_Op (N, Ctx_Type);
2757
2758 when N_Op_Eq | N_Op_Ne
2759 => Resolve_Equality_Op (N, Ctx_Type);
2760
2761 when N_Op_Lt | N_Op_Le | N_Op_Gt | N_Op_Ge
2762 => Resolve_Comparison_Op (N, Ctx_Type);
2763
2764 when N_Op_Not => Resolve_Op_Not (N, Ctx_Type);
2765
2766 when N_Op_Add | N_Op_Subtract | N_Op_Multiply |
2767 N_Op_Divide | N_Op_Mod | N_Op_Rem
2768
2769 => Resolve_Arithmetic_Op (N, Ctx_Type);
2770
2771 when N_Op_Concat => Resolve_Op_Concat (N, Ctx_Type);
2772
2773 when N_Op_Expon => Resolve_Op_Expon (N, Ctx_Type);
2774
2775 when N_Op_Plus | N_Op_Minus | N_Op_Abs
2776 => Resolve_Unary_Op (N, Ctx_Type);
2777
2778 when N_Op_Shift => Resolve_Shift (N, Ctx_Type);
2779
2780 when N_Procedure_Call_Statement
2781 => Resolve_Call (N, Ctx_Type);
2782
2783 when N_Operator_Symbol
2784 => Resolve_Operator_Symbol (N, Ctx_Type);
2785
2786 when N_Qualified_Expression
2787 => Resolve_Qualified_Expression (N, Ctx_Type);
2788
804670f1 2789 when N_Quantified_Expression => null;
a961aa79 2790
996ae0b0
RK		 2791 when N_Raise_xxx_Error
2792 => Set_Etype (N, Ctx_Type);
2793
2794 when N_Range => Resolve_Range (N, Ctx_Type);
2795
2796 when N_Real_Literal
2797 => Resolve_Real_Literal (N, Ctx_Type);
2798
2799 when N_Reference => Resolve_Reference (N, Ctx_Type);
2800
2801 when N_Selected_Component
2802 => Resolve_Selected_Component (N, Ctx_Type);
2803
2804 when N_Slice => Resolve_Slice (N, Ctx_Type);
2805
2806 when N_String_Literal
2807 => Resolve_String_Literal (N, Ctx_Type);
2808
2809 when N_Subprogram_Info
2810 => Resolve_Subprogram_Info (N, Ctx_Type);
2811
2812 when N_Type_Conversion
2813 => Resolve_Type_Conversion (N, Ctx_Type);
2814
2815 when N_Unchecked_Expression =>
2816 Resolve_Unchecked_Expression (N, Ctx_Type);
2817
2818 when N_Unchecked_Type_Conversion =>
2819 Resolve_Unchecked_Type_Conversion (N, Ctx_Type);
996ae0b0
RK		 2820 end case;
2821
6cce2156
GD		 2822 -- Ada 2012 (AI05-0149): Apply an (implicit) conversion to an
2823 -- expression of an anonymous access type that occurs in the context
2824 -- of a named general access type, except when the expression is that
2825 -- of a membership test. This ensures proper legality checking in
2826 -- terms of allowed conversions (expressions that would be illegal to
2827 -- convert implicitly are allowed in membership tests).
2828
2829 if Ada_Version >= Ada_2012
2830 and then Ekind (Ctx_Type) = E_General_Access_Type
2831 and then Ekind (Etype (N)) = E_Anonymous_Access_Type
2832 and then Nkind (Parent (N)) not in N_Membership_Test
2833 then
2834 Rewrite (N, Convert_To (Ctx_Type, Relocate_Node (N)));
2835 Analyze_And_Resolve (N, Ctx_Type);
2836 end if;
2837
996ae0b0
RK		 2838 -- If the subexpression was replaced by a non-subexpression, then
2839 -- all we do is to expand it. The only legitimate case we know of
2840 -- is converting procedure call statement to entry call statements,
2841 -- but there may be others, so we are making this test general.
2842
2843 if Nkind (N) not in N_Subexpr then
2844 Debug_A_Exit ("resolving ", N, " (done)");
2845 Expand (N);
2846 return;
2847 end if;
2848
1e194575
AC		 2849 -- AI05-144-2: Check dangerous order dependence within an expression
2850 -- that is not a subexpression. Exclude RHS of an assignment, because
2851 -- both sides may have side-effects and the check must be performed
2852 -- over the statement.
2853
2854 if Nkind (Parent (N)) not in N_Subexpr
2855 and then Nkind (Parent (N)) /= N_Assignment_Statement
2856 and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
2857 then
2858 Check_Order_Dependence;
2859 end if;
2860
996ae0b0
RK		 2861 -- The expression is definitely NOT overloaded at this point, so
2862 -- we reset the Is_Overloaded flag to avoid any confusion when
2863 -- reanalyzing the node.
2864
2865 Set_Is_Overloaded (N, False);
2866
2867 -- Freeze expression type, entity if it is a name, and designated
fbf5a39b 2868 -- type if it is an allocator (RM 13.14(10,11,13)).
996ae0b0 2869
5cc9353d
RD		 2870 -- Now that the resolution of the type of the node is complete, and
2871 -- we did not detect an error, we can expand this node. We skip the
2872 -- expand call if we are in a default expression, see section
2873 -- "Handling of Default Expressions" in Sem spec.
996ae0b0
RK		 2874
2875 Debug_A_Exit ("resolving ", N, " (done)");
2876
2877 -- We unconditionally freeze the expression, even if we are in
5cc9353d
RD		 2878 -- default expression mode (the Freeze_Expression routine tests this
2879 -- flag and only freezes static types if it is set).
996ae0b0 2880
95160516 2881 -- Ada 2012 (AI05-177): Expression functions do not freeze. Only
08f8a983
AC		 2882 -- their use (in an expanded call) freezes.
2883
804670f1
AC		 2884 if Ekind (Proper_Current_Scope) /= E_Function
2885 or else Nkind (Original_Node (Unit_Declaration_Node
2886 (Proper_Current_Scope))) /= N_Expression_Function
08f8a983
AC		 2887 then
2888 Freeze_Expression (N);
2889 end if;
996ae0b0
RK		 2890
2891 -- Now we can do the expansion
2892
2893 Expand (N);
2894 end if;
996ae0b0
RK		 2895 end Resolve;
2896
fbf5a39b
AC		 2897 -------------
2898 -- Resolve --
2899 -------------
2900
996ae0b0
RK		 2901 -- Version with check(s) suppressed
2902
2903 procedure Resolve (N : Node_Id; Typ : Entity_Id; Suppress : Check_Id) is
2904 begin
2905 if Suppress = All_Checks then
2906 declare
fbf5a39b 2907 Svg : constant Suppress_Array := Scope_Suppress;
996ae0b0
RK		 2908 begin
2909 Scope_Suppress := (others => True);
2910 Resolve (N, Typ);
2911 Scope_Suppress := Svg;
2912 end;
2913
2914 else
2915 declare
fbf5a39b 2916 Svg : constant Boolean := Scope_Suppress (Suppress);
996ae0b0 2917 begin
fbf5a39b 2918 Scope_Suppress (Suppress) := True;
996ae0b0 2919 Resolve (N, Typ);
fbf5a39b 2920 Scope_Suppress (Suppress) := Svg;
996ae0b0
RK		 2921 end;
2922 end if;
2923 end Resolve;
2924
fbf5a39b
AC		 2925 -------------
2926 -- Resolve --
2927 -------------
2928
2929 -- Version with implicit type
2930
2931 procedure Resolve (N : Node_Id) is
2932 begin
2933 Resolve (N, Etype (N));
2934 end Resolve;
2935
996ae0b0
RK		 2936 ---------------------
2937 -- Resolve_Actuals --
2938 ---------------------
2939
2940 procedure Resolve_Actuals (N : Node_Id; Nam : Entity_Id) is
2941 Loc : constant Source_Ptr := Sloc (N);
2942 A : Node_Id;
2943 F : Entity_Id;
2944 A_Typ : Entity_Id;
2945 F_Typ : Entity_Id;
2946 Prev : Node_Id := Empty;
67ce0d7e 2947 Orig_A : Node_Id;
996ae0b0 2948
45fc7ddb
HK		 2949 procedure Check_Argument_Order;
2950 -- Performs a check for the case where the actuals are all simple
2951 -- identifiers that correspond to the formal names, but in the wrong
2952 -- order, which is considered suspicious and cause for a warning.
2953
b7d1f17f
HK		 2954 procedure Check_Prefixed_Call;
2955 -- If the original node is an overloaded call in prefix notation,
2956 -- insert an 'Access or a dereference as needed over the first actual.
2957 -- Try_Object_Operation has already verified that there is a valid
2958 -- interpretation, but the form of the actual can only be determined
2959 -- once the primitive operation is identified.
2960
996ae0b0
RK		 2961 procedure Insert_Default;
2962 -- If the actual is missing in a call, insert in the actuals list
2963 -- an instance of the default expression. The insertion is always
2964 -- a named association.
2965
fbf5a39b
AC		 2966 function Same_Ancestor (T1, T2 : Entity_Id) return Boolean;
2967 -- Check whether T1 and T2, or their full views, are derived from a
2968 -- common type. Used to enforce the restrictions on array conversions
2969 -- of AI95-00246.
2970
a7a3cf5c
AC		 2971 function Static_Concatenation (N : Node_Id) return Boolean;
2972 -- Predicate to determine whether an actual that is a concatenation
2973 -- will be evaluated statically and does not need a transient scope.
2974 -- This must be determined before the actual is resolved and expanded
2975 -- because if needed the transient scope must be introduced earlier.
2976
45fc7ddb
HK		 2977 --------------------------
2978 -- Check_Argument_Order --
2979 --------------------------
2980
2981 procedure Check_Argument_Order is
2982 begin
2983 -- Nothing to do if no parameters, or original node is neither a
2984 -- function call nor a procedure call statement (happens in the
2985 -- operator-transformed-to-function call case), or the call does
2986 -- not come from source, or this warning is off.
2987
2988 if not Warn_On_Parameter_Order
19fb051c 2989 or else No (Parameter_Associations (N))
d3b00ce3 2990 or else Nkind (Original_Node (N)) not in N_Subprogram_Call
19fb051c 2991 or else not Comes_From_Source (N)
45fc7ddb
HK		 2992 then
2993 return;
2994 end if;
2995
2996 declare
2997 Nargs : constant Nat := List_Length (Parameter_Associations (N));
2998
2999 begin
3000 -- Nothing to do if only one parameter
3001
3002 if Nargs < 2 then
3003 return;
3004 end if;
3005
3006 -- Here if at least two arguments
3007
3008 declare
3009 Actuals : array (1 .. Nargs) of Node_Id;
3010 Actual : Node_Id;
3011 Formal : Node_Id;
3012
3013 Wrong_Order : Boolean := False;
3014 -- Set True if an out of order case is found
3015
3016 begin
3017 -- Collect identifier names of actuals, fail if any actual is
3018 -- not a simple identifier, and record max length of name.
3019
3020 Actual := First (Parameter_Associations (N));
3021 for J in Actuals'Range loop
3022 if Nkind (Actual) /= N_Identifier then
3023 return;
3024 else
3025 Actuals (J) := Actual;
3026 Next (Actual);
3027 end if;
3028 end loop;
3029
3030 -- If we got this far, all actuals are identifiers and the list
3031 -- of their names is stored in the Actuals array.
3032
3033 Formal := First_Formal (Nam);
3034 for J in Actuals'Range loop
3035
3036 -- If we ran out of formals, that's odd, probably an error
3037 -- which will be detected elsewhere, but abandon the search.
3038
3039 if No (Formal) then
3040 return;
3041 end if;
3042
3043 -- If name matches and is in order OK
3044
3045 if Chars (Formal) = Chars (Actuals (J)) then
3046 null;
3047
3048 else
3049 -- If no match, see if it is elsewhere in list and if so
3050 -- flag potential wrong order if type is compatible.
3051
3052 for K in Actuals'Range loop
3053 if Chars (Formal) = Chars (Actuals (K))
3054 and then
3055 Has_Compatible_Type (Actuals (K), Etype (Formal))
3056 then
3057 Wrong_Order := True;
3058 goto Continue;
3059 end if;
3060 end loop;
3061
3062 -- No match
3063
3064 return;
3065 end if;
3066
3067 <<Continue>> Next_Formal (Formal);
3068 end loop;
3069
3070 -- If Formals left over, also probably an error, skip warning
3071
3072 if Present (Formal) then
3073 return;
3074 end if;
3075
3076 -- Here we give the warning if something was out of order
3077
3078 if Wrong_Order then
3079 Error_Msg_N
3080 ("actuals for this call may be in wrong order?", N);
3081 end if;
3082 end;
3083 end;
3084 end Check_Argument_Order;
3085
b7d1f17f
HK		 3086 -------------------------
3087 -- Check_Prefixed_Call --
3088 -------------------------
3089
3090 procedure Check_Prefixed_Call is
3091 Act : constant Node_Id := First_Actual (N);
3092 A_Type : constant Entity_Id := Etype (Act);
3093 F_Type : constant Entity_Id := Etype (First_Formal (Nam));
3094 Orig : constant Node_Id := Original_Node (N);
3095 New_A : Node_Id;
3096
3097 begin
3098 -- Check whether the call is a prefixed call, with or without
3099 -- additional actuals.
3100
3101 if Nkind (Orig) = N_Selected_Component
3102 or else
3103 (Nkind (Orig) = N_Indexed_Component
3104 and then Nkind (Prefix (Orig)) = N_Selected_Component
3105 and then Is_Entity_Name (Prefix (Prefix (Orig)))
3106 and then Is_Entity_Name (Act)
3107 and then Chars (Act) = Chars (Prefix (Prefix (Orig))))
3108 then
3109 if Is_Access_Type (A_Type)
3110 and then not Is_Access_Type (F_Type)
3111 then
3112 -- Introduce dereference on object in prefix
3113
3114 New_A :=
3115 Make_Explicit_Dereference (Sloc (Act),
3116 Prefix => Relocate_Node (Act));
3117 Rewrite (Act, New_A);
3118 Analyze (Act);
3119
3120 elsif Is_Access_Type (F_Type)
3121 and then not Is_Access_Type (A_Type)
3122 then
3123 -- Introduce an implicit 'Access in prefix
3124
3125 if not Is_Aliased_View (Act) then
ed2233dc 3126 Error_Msg_NE
b7d1f17f 3127 ("object in prefixed call to& must be aliased"
aa5147f0 3128 & " (RM-2005 4.3.1 (13))",
b7d1f17f
HK		 3129 Prefix (Act), Nam);
3130 end if;
3131
3132 Rewrite (Act,
3133 Make_Attribute_Reference (Loc,
3134 Attribute_Name => Name_Access,
3135 Prefix => Relocate_Node (Act)));
3136 end if;
3137
3138 Analyze (Act);
3139 end if;
3140 end Check_Prefixed_Call;
3141
996ae0b0
RK		 3142 --------------------
3143 -- Insert_Default --
3144 --------------------
3145
3146 procedure Insert_Default is
3147 Actval : Node_Id;
3148 Assoc : Node_Id;
3149
3150 begin
fbf5a39b 3151 -- Missing argument in call, nothing to insert
996ae0b0 3152
fbf5a39b
AC		 3153 if No (Default_Value (F)) then
3154 return;
3155
3156 else
3157 -- Note that we do a full New_Copy_Tree, so that any associated
3158 -- Itypes are properly copied. This may not be needed any more,
3159 -- but it does no harm as a safety measure! Defaults of a generic
3160 -- formal may be out of bounds of the corresponding actual (see
3161 -- cc1311b) and an additional check may be required.
996ae0b0 3162
b7d1f17f
HK		 3163 Actval :=
3164 New_Copy_Tree
3165 (Default_Value (F),
3166 New_Scope => Current_Scope,
3167 New_Sloc => Loc);
996ae0b0
RK		 3168
3169 if Is_Concurrent_Type (Scope (Nam))
3170 and then Has_Discriminants (Scope (Nam))
3171 then
3172 Replace_Actual_Discriminants (N, Actval);
3173 end if;
3174
3175 if Is_Overloadable (Nam)
3176 and then Present (Alias (Nam))
3177 then
3178 if Base_Type (Etype (F)) /= Base_Type (Etype (Actval))
3179 and then not Is_Tagged_Type (Etype (F))
3180 then
3181 -- If default is a real literal, do not introduce a
3182 -- conversion whose effect may depend on the run-time
3183 -- size of universal real.
3184
3185 if Nkind (Actval) = N_Real_Literal then
3186 Set_Etype (Actval, Base_Type (Etype (F)));
3187 else
3188 Actval := Unchecked_Convert_To (Etype (F), Actval);
3189 end if;
3190 end if;
3191
3192 if Is_Scalar_Type (Etype (F)) then
3193 Enable_Range_Check (Actval);
3194 end if;
3195
996ae0b0
RK		 3196 Set_Parent (Actval, N);
3197
3198 -- Resolve aggregates with their base type, to avoid scope
f3d57416 3199 -- anomalies: the subtype was first built in the subprogram
996ae0b0
RK		 3200 -- declaration, and the current call may be nested.
3201
76b84bf0
AC		 3202 if Nkind (Actval) = N_Aggregate then
3203 Analyze_And_Resolve (Actval, Etype (F));
996ae0b0
RK		 3204 else
3205 Analyze_And_Resolve (Actval, Etype (Actval));
3206 end if;
fbf5a39b
AC		 3207
3208 else
3209 Set_Parent (Actval, N);
3210
a77842bd 3211 -- See note above concerning aggregates
fbf5a39b
AC		 3212
3213 if Nkind (Actval) = N_Aggregate
3214 and then Has_Discriminants (Etype (Actval))
3215 then
3216 Analyze_And_Resolve (Actval, Base_Type (Etype (Actval)));
3217
5cc9353d
RD		 3218 -- Resolve entities with their own type, which may differ from
3219 -- the type of a reference in a generic context (the view
3220 -- swapping mechanism did not anticipate the re-analysis of
3221 -- default values in calls).
fbf5a39b
AC		 3222
3223 elsif Is_Entity_Name (Actval) then
3224 Analyze_And_Resolve (Actval, Etype (Entity (Actval)));
3225
3226 else
3227 Analyze_And_Resolve (Actval, Etype (Actval));
3228 end if;
996ae0b0
RK		 3229 end if;
3230
5cc9353d
RD		 3231 -- If default is a tag indeterminate function call, propagate tag
3232 -- to obtain proper dispatching.
996ae0b0
RK		 3233
3234 if Is_Controlling_Formal (F)
3235 and then Nkind (Default_Value (F)) = N_Function_Call
3236 then
3237 Set_Is_Controlling_Actual (Actval);
3238 end if;
3239
996ae0b0
RK		 3240 end if;
3241
3242 -- If the default expression raises constraint error, then just
5cc9353d
RD		 3243 -- silently replace it with an N_Raise_Constraint_Error node, since
3244 -- we already gave the warning on the subprogram spec. If node is
3245 -- already a Raise_Constraint_Error leave as is, to prevent loops in
3246 -- the warnings removal machinery.
996ae0b0 3247
2604ec03
AC		 3248 if Raises_Constraint_Error (Actval)
3249 and then Nkind (Actval) /= N_Raise_Constraint_Error
3250 then
996ae0b0 3251 Rewrite (Actval,
07fc65c4
GB		 3252 Make_Raise_Constraint_Error (Loc,
3253 Reason => CE_Range_Check_Failed));
996ae0b0
RK		 3254 Set_Raises_Constraint_Error (Actval);
3255 Set_Etype (Actval, Etype (F));
3256 end if;
3257
3258 Assoc :=
3259 Make_Parameter_Association (Loc,
3260 Explicit_Actual_Parameter => Actval,
3261 Selector_Name => Make_Identifier (Loc, Chars (F)));
3262
3263 -- Case of insertion is first named actual
3264
3265 if No (Prev) or else
3266 Nkind (Parent (Prev)) /= N_Parameter_Association
3267 then
3268 Set_Next_Named_Actual (Assoc, First_Named_Actual (N));
3269 Set_First_Named_Actual (N, Actval);
3270
3271 if No (Prev) then
c8ef728f 3272 if No (Parameter_Associations (N)) then
996ae0b0
RK		 3273 Set_Parameter_Associations (N, New_List (Assoc));
3274 else
3275 Append (Assoc, Parameter_Associations (N));
3276 end if;
3277
3278 else
3279 Insert_After (Prev, Assoc);
3280 end if;
3281
3282 -- Case of insertion is not first named actual
3283
3284 else
3285 Set_Next_Named_Actual
3286 (Assoc, Next_Named_Actual (Parent (Prev)));
3287 Set_Next_Named_Actual (Parent (Prev), Actval);
3288 Append (Assoc, Parameter_Associations (N));
3289 end if;
3290
3291 Mark_Rewrite_Insertion (Assoc);
3292 Mark_Rewrite_Insertion (Actval);
3293
3294 Prev := Actval;
3295 end Insert_Default;
3296
fbf5a39b
AC		 3297 -------------------
3298 -- Same_Ancestor --
3299 -------------------
3300
3301 function Same_Ancestor (T1, T2 : Entity_Id) return Boolean is
3302 FT1 : Entity_Id := T1;
3303 FT2 : Entity_Id := T2;
3304
3305 begin
3306 if Is_Private_Type (T1)
3307 and then Present (Full_View (T1))
3308 then
3309 FT1 := Full_View (T1);
3310 end if;
3311
3312 if Is_Private_Type (T2)
3313 and then Present (Full_View (T2))
3314 then
3315 FT2 := Full_View (T2);
3316 end if;
3317
3318 return Root_Type (Base_Type (FT1)) = Root_Type (Base_Type (FT2));
3319 end Same_Ancestor;
3320
a7a3cf5c
AC		 3321 --------------------------
3322 -- Static_Concatenation --
3323 --------------------------
3324
3325 function Static_Concatenation (N : Node_Id) return Boolean is
3326 begin
c72a85f2
TQ		 3327 case Nkind (N) is
3328 when N_String_Literal =>
3329 return True;
a7a3cf5c 3330
d81b4bfe
TQ		 3331 when N_Op_Concat =>
3332
5cc9353d
RD		 3333 -- Concatenation is static when both operands are static and
3334 -- the concatenation operator is a predefined one.
4342eda9
TQ		 3335
3336 return Scope (Entity (N)) = Standard_Standard
3337 and then
3338 Static_Concatenation (Left_Opnd (N))
c72a85f2
TQ		 3339 and then
3340 Static_Concatenation (Right_Opnd (N));
3341
3342 when others =>
3343 if Is_Entity_Name (N) then
3344 declare
3345 Ent : constant Entity_Id := Entity (N);
3346 begin
3347 return Ekind (Ent) = E_Constant
3348 and then Present (Constant_Value (Ent))
d81b4bfe
TQ		 3349 and then
3350 Is_Static_Expression (Constant_Value (Ent));
c72a85f2 3351 end;
a7a3cf5c 3352
a7a3cf5c
AC		 3353 else
3354 return False;
3355 end if;
c72a85f2 3356 end case;
a7a3cf5c
AC		 3357 end Static_Concatenation;
3358
996ae0b0
RK		 3359 -- Start of processing for Resolve_Actuals
3360
3361 begin
45fc7ddb
HK		 3362 Check_Argument_Order;
3363
b7d1f17f
HK		 3364 if Present (First_Actual (N)) then
3365 Check_Prefixed_Call;
3366 end if;
3367
996ae0b0
RK		 3368 A := First_Actual (N);
3369 F := First_Formal (Nam);
996ae0b0 3370 while Present (F) loop
fbf5a39b
AC		 3371 if No (A) and then Needs_No_Actuals (Nam) then
3372 null;
996ae0b0 3373
d81b4bfe
TQ		 3374 -- If we have an error in any actual or formal, indicated by a type
3375 -- of Any_Type, then abandon resolution attempt, and set result type
3376 -- to Any_Type.
07fc65c4 3377
fbf5a39b
AC		 3378 elsif (Present (A) and then Etype (A) = Any_Type)
3379 or else Etype (F) = Any_Type
07fc65c4
GB		 3380 then
3381 Set_Etype (N, Any_Type);
3382 return;
3383 end if;
3384
e65f50ec
ES		 3385 -- Case where actual is present
3386
45fc7ddb 3387 -- If the actual is an entity, generate a reference to it now. We
36fcf362
RD		 3388 -- do this before the actual is resolved, because a formal of some
3389 -- protected subprogram, or a task discriminant, will be rewritten
5cc9353d 3390 -- during expansion, and the source entity reference may be lost.
36fcf362
RD		 3391
3392 if Present (A)
3393 and then Is_Entity_Name (A)
3394 and then Comes_From_Source (N)
3395 then
3396 Orig_A := Entity (A);
3397
3398 if Present (Orig_A) then
3399 if Is_Formal (Orig_A)
3400 and then Ekind (F) /= E_In_Parameter
3401 then
3402 Generate_Reference (Orig_A, A, 'm');
19fb051c 3403
36fcf362
RD		 3404 elsif not Is_Overloaded (A) then
3405 Generate_Reference (Orig_A, A);
3406 end if;
3407 end if;
3408 end if;
3409
996ae0b0
RK		 3410 if Present (A)
3411 and then (Nkind (Parent (A)) /= N_Parameter_Association
19fb051c 3412 or else Chars (Selector_Name (Parent (A))) = Chars (F))
996ae0b0 3413 then
45fc7ddb
HK		 3414 -- If style checking mode on, check match of formal name
3415
3416 if Style_Check then
3417 if Nkind (Parent (A)) = N_Parameter_Association then
3418 Check_Identifier (Selector_Name (Parent (A)), F);
3419 end if;
3420 end if;
3421
996ae0b0
RK		 3422 -- If the formal is Out or In_Out, do not resolve and expand the
3423 -- conversion, because it is subsequently expanded into explicit
3424 -- temporaries and assignments. However, the object of the
ea985d95
RD		 3425 -- conversion can be resolved. An exception is the case of tagged
3426 -- type conversion with a class-wide actual. In that case we want
3427 -- the tag check to occur and no temporary will be needed (no
3428 -- representation change can occur) and the parameter is passed by
3429 -- reference, so we go ahead and resolve the type conversion.
c8ef728f 3430 -- Another exception is the case of reference to component or
ea985d95
RD		 3431 -- subcomponent of a bit-packed array, in which case we want to
3432 -- defer expansion to the point the in and out assignments are
3433 -- performed.
996ae0b0
RK		 3434
3435 if Ekind (F) /= E_In_Parameter
3436 and then Nkind (A) = N_Type_Conversion
3437 and then not Is_Class_Wide_Type (Etype (Expression (A)))
3438 then
07fc65c4
GB		 3439 if Ekind (F) = E_In_Out_Parameter
3440 and then Is_Array_Type (Etype (F))
07fc65c4 3441 then
038140ed
AC		 3442 -- In a view conversion, the conversion must be legal in
3443 -- both directions, and thus both component types must be
3444 -- aliased, or neither (4.6 (8)).
758c442c 3445
038140ed
AC		 3446 -- The extra rule in 4.6 (24.9.2) seems unduly restrictive:
3447 -- the privacy requirement should not apply to generic
3448 -- types, and should be checked in an instance. ARG query
3449 -- is in order ???
45fc7ddb 3450
038140ed
AC		 3451 if Has_Aliased_Components (Etype (Expression (A))) /=
3452 Has_Aliased_Components (Etype (F))
3453 then
45fc7ddb
HK		 3454 Error_Msg_N
3455 ("both component types in a view conversion must be"
3456 & " aliased, or neither", A);
3457
038140ed
AC		 3458 -- Comment here??? what set of cases???
3459
45fc7ddb
HK		 3460 elsif
3461 not Same_Ancestor (Etype (F), Etype (Expression (A)))
3462 then
038140ed
AC		 3463 -- Check view conv between unrelated by ref array types
3464
45fc7ddb
HK		 3465 if Is_By_Reference_Type (Etype (F))
3466 or else Is_By_Reference_Type (Etype (Expression (A)))
758c442c
GD		 3467 then
3468 Error_Msg_N
45fc7ddb
HK		 3469 ("view conversion between unrelated by reference " &
3470 "array types not allowed (\'A'I-00246)", A);
038140ed
AC		 3471
3472 -- In Ada 2005 mode, check view conversion component
3473 -- type cannot be private, tagged, or volatile. Note
3474 -- that we only apply this to source conversions. The
3475 -- generated code can contain conversions which are
3476 -- not subject to this test, and we cannot extract the
3477 -- component type in such cases since it is not present.
3478
3479 elsif Comes_From_Source (A)
3480 and then Ada_Version >= Ada_2005
3481 then
45fc7ddb
HK		 3482 declare
3483 Comp_Type : constant Entity_Id :=
3484 Component_Type
3485 (Etype (Expression (A)));
3486 begin
038140ed
AC		 3487 if (Is_Private_Type (Comp_Type)
3488 and then not Is_Generic_Type (Comp_Type))
3489 or else Is_Tagged_Type (Comp_Type)
3490 or else Is_Volatile (Comp_Type)
45fc7ddb
HK		 3491 then
3492 Error_Msg_N
3493 ("component type of a view conversion cannot"
3494 & " be private, tagged, or volatile"
3495 & " (RM 4.6 (24))",
3496 Expression (A));
3497 end if;
3498 end;
758c442c 3499 end if;
fbf5a39b 3500 end if;
07fc65c4
GB		 3501 end if;
3502
038140ed
AC		 3503 -- Resolve expression if conversion is all OK
3504
16397eff 3505 if (Conversion_OK (A)
038140ed 3506 or else Valid_Conversion (A, Etype (A), Expression (A)))
16397eff 3507 and then not Is_Ref_To_Bit_Packed_Array (Expression (A))
996ae0b0 3508 then
fbf5a39b 3509 Resolve (Expression (A));
996ae0b0
RK		 3510 end if;
3511
b7d1f17f
HK		 3512 -- If the actual is a function call that returns a limited
3513 -- unconstrained object that needs finalization, create a
3514 -- transient scope for it, so that it can receive the proper
3515 -- finalization list.
3516
3517 elsif Nkind (A) = N_Function_Call
3518 and then Is_Limited_Record (Etype (F))
3519 and then not Is_Constrained (Etype (F))
da94696d 3520 and then Full_Expander_Active
19fb051c 3521 and then (Is_Controlled (Etype (F)) or else Has_Task (Etype (F)))
b7d1f17f
HK		 3522 then
3523 Establish_Transient_Scope (A, False);
24a120ac 3524 Resolve (A, Etype (F));
b7d1f17f 3525
a52fefe6
AC		 3526 -- A small optimization: if one of the actuals is a concatenation
3527 -- create a block around a procedure call to recover stack space.
3528 -- This alleviates stack usage when several procedure calls in
76e776e5
AC		 3529 -- the same statement list use concatenation. We do not perform
3530 -- this wrapping for code statements, where the argument is a
3531 -- static string, and we want to preserve warnings involving
3532 -- sequences of such statements.
a52fefe6
AC		 3533
3534 elsif Nkind (A) = N_Op_Concat
3535 and then Nkind (N) = N_Procedure_Call_Statement
da94696d 3536 and then Full_Expander_Active
76e776e5
AC		 3537 and then
3538 not (Is_Intrinsic_Subprogram (Nam)
3539 and then Chars (Nam) = Name_Asm)
a7a3cf5c 3540 and then not Static_Concatenation (A)
a52fefe6
AC		 3541 then
3542 Establish_Transient_Scope (A, False);
3543 Resolve (A, Etype (F));
3544
996ae0b0 3545 else
fbf5a39b
AC		 3546 if Nkind (A) = N_Type_Conversion
3547 and then Is_Array_Type (Etype (F))
3548 and then not Same_Ancestor (Etype (F), Etype (Expression (A)))
3549 and then
3550 (Is_Limited_Type (Etype (F))
3551 or else Is_Limited_Type (Etype (Expression (A))))
3552 then
3553 Error_Msg_N
758c442c
GD		 3554 ("conversion between unrelated limited array types " &
3555 "not allowed (\A\I-00246)", A);
fbf5a39b 3556
758c442c
GD		 3557 if Is_Limited_Type (Etype (F)) then
3558 Explain_Limited_Type (Etype (F), A);
3559 end if;
fbf5a39b 3560
758c442c
GD		 3561 if Is_Limited_Type (Etype (Expression (A))) then
3562 Explain_Limited_Type (Etype (Expression (A)), A);
3563 end if;
fbf5a39b
AC		 3564 end if;
3565
c8ef728f
ES		 3566 -- (Ada 2005: AI-251): If the actual is an allocator whose
3567 -- directly designated type is a class-wide interface, we build
3568 -- an anonymous access type to use it as the type of the
3569 -- allocator. Later, when the subprogram call is expanded, if
3570 -- the interface has a secondary dispatch table the expander
3571 -- will add a type conversion to force the correct displacement
3572 -- of the pointer.
3573
3574 if Nkind (A) = N_Allocator then
3575 declare
3576 DDT : constant Entity_Id :=
3577 Directly_Designated_Type (Base_Type (Etype (F)));
45fc7ddb 3578
c8ef728f 3579 New_Itype : Entity_Id;
45fc7ddb 3580
c8ef728f
ES		 3581 begin
3582 if Is_Class_Wide_Type (DDT)
3583 and then Is_Interface (DDT)
3584 then
3585 New_Itype := Create_Itype (E_Anonymous_Access_Type, A);
45fc7ddb 3586 Set_Etype (New_Itype, Etype (A));
c8ef728f
ES		 3587 Set_Directly_Designated_Type (New_Itype,
3588 Directly_Designated_Type (Etype (A)));
3589 Set_Etype (A, New_Itype);
3590 end if;
0669bebe
GB		 3591
3592 -- Ada 2005, AI-162:If the actual is an allocator, the
3593 -- innermost enclosing statement is the master of the
b7d1f17f
HK		 3594 -- created object. This needs to be done with expansion
3595 -- enabled only, otherwise the transient scope will not
3596 -- be removed in the expansion of the wrapped construct.
0669bebe 3597
45fc7ddb 3598 if (Is_Controlled (DDT) or else Has_Task (DDT))
da94696d 3599 and then Full_Expander_Active
0669bebe
GB		 3600 then
3601 Establish_Transient_Scope (A, False);
3602 end if;
c8ef728f
ES		 3603 end;
3604 end if;
3605
b7d1f17f
HK		 3606 -- (Ada 2005): The call may be to a primitive operation of
3607 -- a tagged synchronized type, declared outside of the type.
3608 -- In this case the controlling actual must be converted to
3609 -- its corresponding record type, which is the formal type.
45fc7ddb
HK		 3610 -- The actual may be a subtype, either because of a constraint
3611 -- or because it is a generic actual, so use base type to
3612 -- locate concurrent type.
b7d1f17f 3613
15e4986c
JM		 3614 F_Typ := Base_Type (Etype (F));
3615
cb7fa356
AC		 3616 if Is_Tagged_Type (F_Typ)
3617 and then (Is_Concurrent_Type (F_Typ)
3618 or else Is_Concurrent_Record_Type (F_Typ))
3619 then
3620 -- If the actual is overloaded, look for an interpretation
3621 -- that has a synchronized type.
3622
3623 if not Is_Overloaded (A) then
3624 A_Typ := Base_Type (Etype (A));
15e4986c 3625
15e4986c 3626 else
cb7fa356
AC		 3627 declare
3628 Index : Interp_Index;
3629 It : Interp;
218e6dee 3630
cb7fa356
AC		 3631 begin
3632 Get_First_Interp (A, Index, It);
3633 while Present (It.Typ) loop
3634 if Is_Concurrent_Type (It.Typ)
3635 or else Is_Concurrent_Record_Type (It.Typ)
3636 then
3637 A_Typ := Base_Type (It.Typ);
3638 exit;
3639 end if;
3640
3641 Get_Next_Interp (Index, It);
3642 end loop;
3643 end;
15e4986c 3644 end if;
b7d1f17f 3645
cb7fa356
AC		 3646 declare
3647 Full_A_Typ : Entity_Id;
15e4986c 3648
cb7fa356
AC		 3649 begin
3650 if Present (Full_View (A_Typ)) then
3651 Full_A_Typ := Base_Type (Full_View (A_Typ));
3652 else
3653 Full_A_Typ := A_Typ;
3654 end if;
3655
3656 -- Tagged synchronized type (case 1): the actual is a
3657 -- concurrent type.
3658
3659 if Is_Concurrent_Type (A_Typ)
3660 and then Corresponding_Record_Type (A_Typ) = F_Typ
3661 then
3662 Rewrite (A,
3663 Unchecked_Convert_To
3664 (Corresponding_Record_Type (A_Typ), A));
3665 Resolve (A, Etype (F));
15e4986c 3666
cb7fa356
AC		 3667 -- Tagged synchronized type (case 2): the formal is a
3668 -- concurrent type.
15e4986c 3669
cb7fa356
AC		 3670 elsif Ekind (Full_A_Typ) = E_Record_Type
3671 and then Present
15e4986c 3672 (Corresponding_Concurrent_Type (Full_A_Typ))
cb7fa356
AC		 3673 and then Is_Concurrent_Type (F_Typ)
3674 and then Present (Corresponding_Record_Type (F_Typ))
3675 and then Full_A_Typ = Corresponding_Record_Type (F_Typ)
3676 then
3677 Resolve (A, Corresponding_Record_Type (F_Typ));
15e4986c 3678
cb7fa356 3679 -- Common case
15e4986c 3680
cb7fa356
AC		 3681 else
3682 Resolve (A, Etype (F));
3683 end if;
3684 end;
3685 else
3686
3687 -- not a synchronized operation.
3688
3689 Resolve (A, Etype (F));
3690 end if;
996ae0b0
RK		 3691 end if;
3692
3693 A_Typ := Etype (A);
3694 F_Typ := Etype (F);
3695
e24329cd 3696 if Comes_From_Source (Original_Node (N))
6320f5e1
AC		 3697 and then Nkind_In (Original_Node (N), N_Function_Call,
3698 N_Procedure_Call_Statement)
b0186f71 3699 then
e24329cd
YM		 3700 -- In formal mode, check that actual parameters matching
3701 -- formals of tagged types are objects (or ancestor type
3702 -- conversions of objects), not general expressions.
780d052e 3703
e24329cd
YM		 3704 if Is_Actual_Tagged_Parameter (A) then
3705 if Is_SPARK_Object_Reference (A) then
3706 null;
3707
3708 elsif Nkind (A) = N_Type_Conversion then
3709 declare
3710 Operand : constant Node_Id := Expression (A);
3711 Operand_Typ : constant Entity_Id := Etype (Operand);
3712 Target_Typ : constant Entity_Id := A_Typ;
3713
3714 begin
3715 if not Is_SPARK_Object_Reference (Operand) then
2ba431e5 3716 Check_SPARK_Restriction
e24329cd
YM		 3717 ("object required", Operand);
3718
3719 -- In formal mode, the only view conversions are those
3720 -- involving ancestor conversion of an extended type.
3721
3722 elsif not
3723 (Is_Tagged_Type (Target_Typ)
780d052e
RD		 3724 and then not Is_Class_Wide_Type (Target_Typ)
3725 and then Is_Tagged_Type (Operand_Typ)
3726 and then not Is_Class_Wide_Type (Operand_Typ)
3727 and then Is_Ancestor (Target_Typ, Operand_Typ))
e24329cd
YM		 3728 then
3729 if Ekind_In
3730 (F, E_Out_Parameter, E_In_Out_Parameter)
3731 then
2ba431e5 3732 Check_SPARK_Restriction
e24329cd
YM		 3733 ("ancestor conversion is the only permitted "
3734 & "view conversion", A);
3735 else
2ba431e5 3736 Check_SPARK_Restriction
e24329cd
YM		 3737 ("ancestor conversion required", A);
3738 end if;
3739
3740 else
3741 null;
3742 end if;
3743 end;
3744
3745 else
2ba431e5 3746 Check_SPARK_Restriction ("object required", A);
b0186f71 3747 end if;
e24329cd
YM		 3748
3749 -- In formal mode, the only view conversions are those
3750 -- involving ancestor conversion of an extended type.
3751
3752 elsif Nkind (A) = N_Type_Conversion
3753 and then Ekind_In (F, E_Out_Parameter, E_In_Out_Parameter)
3754 then
2ba431e5 3755 Check_SPARK_Restriction
e24329cd
YM		 3756 ("ancestor conversion is the only permitted view "
3757 & "conversion", A);
3758 end if;
b0186f71
AC		 3759 end if;
3760
1e194575
AC		 3761 -- Save actual for subsequent check on order dependence, and
3762 -- indicate whether actual is modifiable. For AI05-0144-2.
bb481772 3763
67bdbf1e
AC		 3764 -- If this is a call to a reference function that is the result
3765 -- of expansion, as in element iterator loops, this does not lead
3766 -- to a dangerous order dependence: only subsequent use of the
3767 -- denoted element might, in some enclosing call.
3768
3769 if not Has_Implicit_Dereference (Etype (Nam))
3770 or else Comes_From_Source (N)
3771 then
3772 Save_Actual (A, Ekind (F) /= E_In_Parameter);
3773 end if;
bb481772 3774
26570b21
RD		 3775 -- For mode IN, if actual is an entity, and the type of the formal
3776 -- has warnings suppressed, then we reset Never_Set_In_Source for
3777 -- the calling entity. The reason for this is to catch cases like
3778 -- GNAT.Spitbol.Patterns.Vstring_Var where the called subprogram
3779 -- uses trickery to modify an IN parameter.
3780
3781 if Ekind (F) = E_In_Parameter
3782 and then Is_Entity_Name (A)
3783 and then Present (Entity (A))
3784 and then Ekind (Entity (A)) = E_Variable
3785 and then Has_Warnings_Off (F_Typ)
3786 then
3787 Set_Never_Set_In_Source (Entity (A), False);
3788 end if;
3789
fbf5a39b
AC		 3790 -- Perform error checks for IN and IN OUT parameters
3791
3792 if Ekind (F) /= E_Out_Parameter then
3793
3794 -- Check unset reference. For scalar parameters, it is clearly
3795 -- wrong to pass an uninitialized value as either an IN or
3796 -- IN-OUT parameter. For composites, it is also clearly an
3797 -- error to pass a completely uninitialized value as an IN
3798 -- parameter, but the case of IN OUT is trickier. We prefer
3799 -- not to give a warning here. For example, suppose there is
3800 -- a routine that sets some component of a record to False.
3801 -- It is perfectly reasonable to make this IN-OUT and allow
3802 -- either initialized or uninitialized records to be passed
3803 -- in this case.
3804
3805 -- For partially initialized composite values, we also avoid
3806 -- warnings, since it is quite likely that we are passing a
3807 -- partially initialized value and only the initialized fields
3808 -- will in fact be read in the subprogram.
3809
3810 if Is_Scalar_Type (A_Typ)
3811 or else (Ekind (F) = E_In_Parameter
19fb051c 3812 and then not Is_Partially_Initialized_Type (A_Typ))
996ae0b0 3813 then
fbf5a39b 3814 Check_Unset_Reference (A);
996ae0b0 3815 end if;
996ae0b0 3816
758c442c
GD		 3817 -- In Ada 83 we cannot pass an OUT parameter as an IN or IN OUT
3818 -- actual to a nested call, since this is case of reading an
3819 -- out parameter, which is not allowed.
996ae0b0 3820
0ab80019 3821 if Ada_Version = Ada_83
996ae0b0
RK		 3822 and then Is_Entity_Name (A)
3823 and then Ekind (Entity (A)) = E_Out_Parameter
3824 then
3825 Error_Msg_N ("(Ada 83) illegal reading of out parameter", A);
3826 end if;
3827 end if;
3828
67ce0d7e
RD		 3829 -- Case of OUT or IN OUT parameter
3830
36fcf362 3831 if Ekind (F) /= E_In_Parameter then
67ce0d7e
RD		 3832
3833 -- For an Out parameter, check for useless assignment. Note
45fc7ddb
HK		 3834 -- that we can't set Last_Assignment this early, because we may
3835 -- kill current values in Resolve_Call, and that call would
3836 -- clobber the Last_Assignment field.
67ce0d7e 3837
45fc7ddb
HK		 3838 -- Note: call Warn_On_Useless_Assignment before doing the check
3839 -- below for Is_OK_Variable_For_Out_Formal so that the setting
3840 -- of Referenced_As_LHS/Referenced_As_Out_Formal properly
3841 -- reflects the last assignment, not this one!
36fcf362 3842
67ce0d7e 3843 if Ekind (F) = E_Out_Parameter then
36fcf362 3844 if Warn_On_Modified_As_Out_Parameter (F)
67ce0d7e
RD		 3845 and then Is_Entity_Name (A)
3846 and then Present (Entity (A))
36fcf362 3847 and then Comes_From_Source (N)
67ce0d7e 3848 then
36fcf362 3849 Warn_On_Useless_Assignment (Entity (A), A);
67ce0d7e
RD		 3850 end if;
3851 end if;
3852
36fcf362
RD		 3853 -- Validate the form of the actual. Note that the call to
3854 -- Is_OK_Variable_For_Out_Formal generates the required
3855 -- reference in this case.
3856
0180fd26
AC		 3857 -- A call to an initialization procedure for an aggregate
3858 -- component may initialize a nested component of a constant
3859 -- designated object. In this context the object is variable.
3860
3861 if not Is_OK_Variable_For_Out_Formal (A)
3862 and then not Is_Init_Proc (Nam)
3863 then
36fcf362
RD		 3864 Error_Msg_NE ("actual for& must be a variable", A, F);
3865 end if;
3866
67ce0d7e 3867 -- What's the following about???
fbf5a39b
AC		 3868
3869 if Is_Entity_Name (A) then
3870 Kill_Checks (Entity (A));
3871 else
3872 Kill_All_Checks;
3873 end if;
3874 end if;
3875
3876 if Etype (A) = Any_Type then
3877 Set_Etype (N, Any_Type);
3878 return;
3879 end if;
3880
996ae0b0
RK		 3881 -- Apply appropriate range checks for in, out, and in-out
3882 -- parameters. Out and in-out parameters also need a separate
3883 -- check, if there is a type conversion, to make sure the return
3884 -- value meets the constraints of the variable before the
3885 -- conversion.
3886
3887 -- Gigi looks at the check flag and uses the appropriate types.
3888 -- For now since one flag is used there is an optimization which
3889 -- might not be done in the In Out case since Gigi does not do
3890 -- any analysis. More thought required about this ???
3891
8a95f4e8 3892 if Ekind_In (F, E_In_Parameter, E_In_Out_Parameter) then
48f91b44
RD		 3893
3894 -- Apply predicate checks, unless this is a call to the
3895 -- predicate check function itself, which would cause an
3896 -- infinite recursion.
3897
3898 if not (Ekind (Nam) = E_Function
3899 and then Has_Predicates (Nam))
3900 then
3901 Apply_Predicate_Check (A, F_Typ);
3902 end if;
3903
3904 -- Apply required constraint checks
3905
996ae0b0
RK		 3906 if Is_Scalar_Type (Etype (A)) then
3907 Apply_Scalar_Range_Check (A, F_Typ);
3908
3909 elsif Is_Array_Type (Etype (A)) then
3910 Apply_Length_Check (A, F_Typ);
3911
3912 elsif Is_Record_Type (F_Typ)
3913 and then Has_Discriminants (F_Typ)
3914 and then Is_Constrained (F_Typ)
3915 and then (not Is_Derived_Type (F_Typ)
19fb051c 3916 or else Comes_From_Source (Nam))
996ae0b0
RK		 3917 then
3918 Apply_Discriminant_Check (A, F_Typ);
3919
3920 elsif Is_Access_Type (F_Typ)
3921 and then Is_Array_Type (Designated_Type (F_Typ))
3922 and then Is_Constrained (Designated_Type (F_Typ))
3923 then
3924 Apply_Length_Check (A, F_Typ);
3925
3926 elsif Is_Access_Type (F_Typ)
3927 and then Has_Discriminants (Designated_Type (F_Typ))
3928 and then Is_Constrained (Designated_Type (F_Typ))
3929 then
3930 Apply_Discriminant_Check (A, F_Typ);
3931
3932 else
3933 Apply_Range_Check (A, F_Typ);
3934 end if;
2820d220 3935
0f1a6a0b
AC		 3936 -- Ada 2005 (AI-231): Note that the controlling parameter case
3937 -- already existed in Ada 95, which is partially checked
3938 -- elsewhere (see Checks), and we don't want the warning
3939 -- message to differ.
2820d220 3940
0f1a6a0b 3941 if Is_Access_Type (F_Typ)
1420b484 3942 and then Can_Never_Be_Null (F_Typ)
aa5147f0 3943 and then Known_Null (A)
2820d220 3944 then
0f1a6a0b
AC		 3945 if Is_Controlling_Formal (F) then
3946 Apply_Compile_Time_Constraint_Error
3947 (N => A,
3948 Msg => "null value not allowed here?",
3949 Reason => CE_Access_Check_Failed);
3950
3951 elsif Ada_Version >= Ada_2005 then
3952 Apply_Compile_Time_Constraint_Error
3953 (N => A,
3954 Msg => "(Ada 2005) null not allowed in "
3955 & "null-excluding formal?",
3956 Reason => CE_Null_Not_Allowed);
3957 end if;
2820d220 3958 end if;
996ae0b0
RK		 3959 end if;
3960
8a95f4e8 3961 if Ekind_In (F, E_Out_Parameter, E_In_Out_Parameter) then
996ae0b0
RK		 3962 if Nkind (A) = N_Type_Conversion then
3963 if Is_Scalar_Type (A_Typ) then
3964 Apply_Scalar_Range_Check
3965 (Expression (A), Etype (Expression (A)), A_Typ);
3966 else
3967 Apply_Range_Check
3968 (Expression (A), Etype (Expression (A)), A_Typ);
3969 end if;
3970
3971 else
3972 if Is_Scalar_Type (F_Typ) then
3973 Apply_Scalar_Range_Check (A, A_Typ, F_Typ);
996ae0b0
RK		 3974 elsif Is_Array_Type (F_Typ)
3975 and then Ekind (F) = E_Out_Parameter
3976 then
3977 Apply_Length_Check (A, F_Typ);
996ae0b0
RK		 3978 else
3979 Apply_Range_Check (A, A_Typ, F_Typ);
3980 end if;
3981 end if;
3982 end if;
3983
3984 -- An actual associated with an access parameter is implicitly
45fc7ddb
HK		 3985 -- converted to the anonymous access type of the formal and must
3986 -- satisfy the legality checks for access conversions.
996ae0b0
RK		 3987
3988 if Ekind (F_Typ) = E_Anonymous_Access_Type then
3989 if not Valid_Conversion (A, F_Typ, A) then
3990 Error_Msg_N
3991 ("invalid implicit conversion for access parameter", A);
3992 end if;
de94a7e7
AC		 3993
3994 -- If the actual is an access selected component of a variable,
3995 -- the call may modify its designated object. It is reasonable
3996 -- to treat this as a potential modification of the enclosing
3997 -- record, to prevent spurious warnings that it should be
3998 -- declared as a constant, because intuitively programmers
3999 -- regard the designated subcomponent as part of the record.
4000
4001 if Nkind (A) = N_Selected_Component
4002 and then Is_Entity_Name (Prefix (A))
4003 and then not Is_Constant_Object (Entity (Prefix (A)))
4004 then
4005 Note_Possible_Modification (A, Sure => False);
4006 end if;
996ae0b0
RK		 4007 end if;
4008
4009 -- Check bad case of atomic/volatile argument (RM C.6(12))
4010
4011 if Is_By_Reference_Type (Etype (F))
4012 and then Comes_From_Source (N)
4013 then
4014 if Is_Atomic_Object (A)
4015 and then not Is_Atomic (Etype (F))
4016 then
b5bf3335
AC		 4017 Error_Msg_NE
4018 ("cannot pass atomic argument to non-atomic formal&",
4019 A, F);
996ae0b0
RK		 4020
4021 elsif Is_Volatile_Object (A)
4022 and then not Is_Volatile (Etype (F))
4023 then
b5bf3335
AC		 4024 Error_Msg_NE
4025 ("cannot pass volatile argument to non-volatile formal&",
4026 A, F);
996ae0b0
RK		 4027 end if;
4028 end if;
4029
4030 -- Check that subprograms don't have improper controlling
d81b4bfe 4031 -- arguments (RM 3.9.2 (9)).
996ae0b0 4032
0669bebe
GB		 4033 -- A primitive operation may have an access parameter of an
4034 -- incomplete tagged type, but a dispatching call is illegal
4035 -- if the type is still incomplete.
4036
996ae0b0
RK		 4037 if Is_Controlling_Formal (F) then
4038 Set_Is_Controlling_Actual (A);
0669bebe
GB		 4039
4040 if Ekind (Etype (F)) = E_Anonymous_Access_Type then
4041 declare
4042 Desig : constant Entity_Id := Designated_Type (Etype (F));
4043 begin
4044 if Ekind (Desig) = E_Incomplete_Type
4045 and then No (Full_View (Desig))
4046 and then No (Non_Limited_View (Desig))
4047 then
4048 Error_Msg_NE
4049 ("premature use of incomplete type& " &
4050 "in dispatching call", A, Desig);
4051 end if;
4052 end;
4053 end if;
4054
996ae0b0
RK		 4055 elsif Nkind (A) = N_Explicit_Dereference then
4056 Validate_Remote_Access_To_Class_Wide_Type (A);
4057 end if;
4058
4059 if (Is_Class_Wide_Type (A_Typ) or else Is_Dynamically_Tagged (A))
4060 and then not Is_Class_Wide_Type (F_Typ)
4061 and then not Is_Controlling_Formal (F)
4062 then
4063 Error_Msg_N ("class-wide argument not allowed here!", A);
07fc65c4
GB		 4064
4065 if Is_Subprogram (Nam)
4066 and then Comes_From_Source (Nam)
4067 then
996ae0b0
RK		 4068 Error_Msg_Node_2 := F_Typ;
4069 Error_Msg_NE
82c80734 4070 ("& is not a dispatching operation of &!", A, Nam);
996ae0b0
RK		 4071 end if;
4072
97216ca8
ES		 4073 -- Apply the checks described in 3.10.2(27): if the context is a
4074 -- specific access-to-object, the actual cannot be class-wide.
4075 -- Use base type to exclude access_to_subprogram cases.
4076
996ae0b0
RK		 4077 elsif Is_Access_Type (A_Typ)
4078 and then Is_Access_Type (F_Typ)
97216ca8 4079 and then not Is_Access_Subprogram_Type (Base_Type (F_Typ))
996ae0b0 4080 and then (Is_Class_Wide_Type (Designated_Type (A_Typ))
07fc65c4
GB		 4081 or else (Nkind (A) = N_Attribute_Reference
4082 and then
97216ca8 4083 Is_Class_Wide_Type (Etype (Prefix (A)))))
996ae0b0
RK		 4084 and then not Is_Class_Wide_Type (Designated_Type (F_Typ))
4085 and then not Is_Controlling_Formal (F)
ae65d635 4086
46fe0142 4087 -- Disable these checks for call to imported C++ subprograms
ae65d635 4088
46fe0142
AC		 4089 and then not
4090 (Is_Entity_Name (Name (N))
4091 and then Is_Imported (Entity (Name (N)))
4092 and then Convention (Entity (Name (N))) = Convention_CPP)
996ae0b0
RK		 4093 then
4094 Error_Msg_N
4095 ("access to class-wide argument not allowed here!", A);
07fc65c4 4096
97216ca8 4097 if Is_Subprogram (Nam) and then Comes_From_Source (Nam) then
996ae0b0
RK		 4098 Error_Msg_Node_2 := Designated_Type (F_Typ);
4099 Error_Msg_NE
82c80734 4100 ("& is not a dispatching operation of &!", A, Nam);
996ae0b0
RK		 4101 end if;
4102 end if;
4103
4104 Eval_Actual (A);
4105
8e4dac80 4106 -- If it is a named association, treat the selector_name as a
1f9939b5 4107 -- proper identifier, and mark the corresponding entity. Ignore
56812278 4108 -- this reference in Alfa mode, as it refers to an entity not in
1f9939b5
AC		 4109 -- scope at the point of reference, so the reference should be
4110 -- ignored for computing effects of subprograms.
996ae0b0 4111
1f9939b5 4112 if Nkind (Parent (A)) = N_Parameter_Association
56812278 4113 and then not Alfa_Mode
1f9939b5 4114 then
996ae0b0
RK		 4115 Set_Entity (Selector_Name (Parent (A)), F);
4116 Generate_Reference (F, Selector_Name (Parent (A)));
4117 Set_Etype (Selector_Name (Parent (A)), F_Typ);
4118 Generate_Reference (F_Typ, N, ' ');
4119 end if;
4120
4121 Prev := A;
fbf5a39b
AC		 4122
4123 if Ekind (F) /= E_Out_Parameter then
4124 Check_Unset_Reference (A);
4125 end if;
4126
996ae0b0
RK		 4127 Next_Actual (A);
4128
fbf5a39b
AC		 4129 -- Case where actual is not present
4130
996ae0b0
RK		 4131 else
4132 Insert_Default;
4133 end if;
4134
4135 Next_Formal (F);
4136 end loop;
996ae0b0
RK		 4137 end Resolve_Actuals;
4138
4139 -----------------------
4140 -- Resolve_Allocator --
4141 -----------------------
4142
4143 procedure Resolve_Allocator (N : Node_Id; Typ : Entity_Id) is
949a18cc 4144 Desig_T : constant Entity_Id := Designated_Type (Typ);
ee2e3f6b 4145 E : constant Node_Id := Expression (N);
996ae0b0
RK		 4146 Subtyp : Entity_Id;
4147 Discrim : Entity_Id;
4148 Constr : Node_Id;
b7d1f17f
HK		 4149 Aggr : Node_Id;
4150 Assoc : Node_Id := Empty;
996ae0b0
RK		 4151 Disc_Exp : Node_Id;
4152
b7d1f17f
HK		 4153 procedure Check_Allocator_Discrim_Accessibility
4154 (Disc_Exp : Node_Id;
4155 Alloc_Typ : Entity_Id);
4156 -- Check that accessibility level associated with an access discriminant
4157 -- initialized in an allocator by the expression Disc_Exp is not deeper
4158 -- than the level of the allocator type Alloc_Typ. An error message is
4159 -- issued if this condition is violated. Specialized checks are done for
4160 -- the cases of a constraint expression which is an access attribute or
4161 -- an access discriminant.
4162
07fc65c4 4163 function In_Dispatching_Context return Boolean;
b7d1f17f
HK		 4164 -- If the allocator is an actual in a call, it is allowed to be class-
4165 -- wide when the context is not because it is a controlling actual.
4166
b7d1f17f
HK		 4167 -------------------------------------------
4168 -- Check_Allocator_Discrim_Accessibility --
4169 -------------------------------------------
4170
4171 procedure Check_Allocator_Discrim_Accessibility
4172 (Disc_Exp : Node_Id;
4173 Alloc_Typ : Entity_Id)
4174 is
4175 begin
4176 if Type_Access_Level (Etype (Disc_Exp)) >
f460d8f3 4177 Deepest_Type_Access_Level (Alloc_Typ)
b7d1f17f
HK		 4178 then
4179 Error_Msg_N
4180 ("operand type has deeper level than allocator type", Disc_Exp);
4181
4182 -- When the expression is an Access attribute the level of the prefix
4183 -- object must not be deeper than that of the allocator's type.
4184
4185 elsif Nkind (Disc_Exp) = N_Attribute_Reference
83e5da69
AC		 4186 and then Get_Attribute_Id (Attribute_Name (Disc_Exp)) =
4187 Attribute_Access
4188 and then Object_Access_Level (Prefix (Disc_Exp)) >
4189 Deepest_Type_Access_Level (Alloc_Typ)
b7d1f17f
HK		 4190 then
4191 Error_Msg_N
4192 ("prefix of attribute has deeper level than allocator type",
4193 Disc_Exp);
4194
4195 -- When the expression is an access discriminant the check is against
4196 -- the level of the prefix object.
4197
4198 elsif Ekind (Etype (Disc_Exp)) = E_Anonymous_Access_Type
4199 and then Nkind (Disc_Exp) = N_Selected_Component
83e5da69
AC		 4200 and then Object_Access_Level (Prefix (Disc_Exp)) >
4201 Deepest_Type_Access_Level (Alloc_Typ)
b7d1f17f
HK		 4202 then
4203 Error_Msg_N
4204 ("access discriminant has deeper level than allocator type",
4205 Disc_Exp);
4206
4207 -- All other cases are legal
4208
4209 else
4210 null;
4211 end if;
4212 end Check_Allocator_Discrim_Accessibility;
07fc65c4
GB		 4213
4214 ----------------------------
4215 -- In_Dispatching_Context --
4216 ----------------------------
4217
4218 function In_Dispatching_Context return Boolean is
4219 Par : constant Node_Id := Parent (N);
b7d1f17f
HK		 4220
4221 begin
d3b00ce3
AC		 4222 return Nkind (Par) in N_Subprogram_Call
4223 and then Is_Entity_Name (Name (Par))
4224 and then Is_Dispatching_Operation (Entity (Name (Par)));
df3e68b1 4225 end In_Dispatching_Context;
b7d1f17f 4226
07fc65c4
GB		 4227 -- Start of processing for Resolve_Allocator
4228
996ae0b0
RK		 4229 begin
4230 -- Replace general access with specific type
4231
4232 if Ekind (Etype (N)) = E_Allocator_Type then
4233 Set_Etype (N, Base_Type (Typ));
4234 end if;
4235
0669bebe 4236 if Is_Abstract_Type (Typ) then
996ae0b0
RK		 4237 Error_Msg_N ("type of allocator cannot be abstract", N);
4238 end if;
4239
4240 -- For qualified expression, resolve the expression using the
4241 -- given subtype (nothing to do for type mark, subtype indication)
4242
4243 if Nkind (E) = N_Qualified_Expression then
4244 if Is_Class_Wide_Type (Etype (E))
949a18cc 4245 and then not Is_Class_Wide_Type (Desig_T)
07fc65c4 4246 and then not In_Dispatching_Context
996ae0b0
RK		 4247 then
4248 Error_Msg_N
4249 ("class-wide allocator not allowed for this access type", N);
4250 end if;
4251
4252 Resolve (Expression (E), Etype (E));
4253 Check_Unset_Reference (Expression (E));
4254
fbf5a39b 4255 -- A qualified expression requires an exact match of the type,
7b4db06c 4256 -- class-wide matching is not allowed.
fbf5a39b 4257
7b4db06c 4258 if (Is_Class_Wide_Type (Etype (Expression (E)))
19fb051c 4259 or else Is_Class_Wide_Type (Etype (E)))
fbf5a39b
AC		 4260 and then Base_Type (Etype (Expression (E))) /= Base_Type (Etype (E))
4261 then
4262 Wrong_Type (Expression (E), Etype (E));
4263 end if;
4264
a8551b5f
AC		 4265 -- Calls to build-in-place functions are not currently supported in
4266 -- allocators for access types associated with a simple storage pool.
4267 -- Supporting such allocators may require passing additional implicit
4268 -- parameters to build-in-place functions (or a significant revision
4269 -- of the current b-i-p implementation to unify the handling for
4270 -- multiple kinds of storage pools). ???
4271
4272 if Is_Immutably_Limited_Type (Desig_T)
4273 and then Nkind (Expression (E)) = N_Function_Call
4274 then
4275 declare
260359e3
AC		 4276 Pool : constant Entity_Id :=
4277 Associated_Storage_Pool (Root_Type (Typ));
a8551b5f
AC		 4278 begin
4279 if Present (Pool)
f6205414
AC		 4280 and then
4281 Present (Get_Rep_Pragma
4282 (Etype (Pool), Name_Simple_Storage_Pool_Type))
a8551b5f
AC		 4283 then
4284 Error_Msg_N
4285 ("limited function calls not yet supported in simple " &
4286 "storage pool allocators", Expression (E));
4287 end if;
4288 end;
4289 end if;
4290
b7d1f17f
HK		 4291 -- A special accessibility check is needed for allocators that
4292 -- constrain access discriminants. The level of the type of the
4293 -- expression used to constrain an access discriminant cannot be
f3d57416 4294 -- deeper than the type of the allocator (in contrast to access
b7d1f17f
HK		 4295 -- parameters, where the level of the actual can be arbitrary).
4296
4297 -- We can't use Valid_Conversion to perform this check because
4298 -- in general the type of the allocator is unrelated to the type
4299 -- of the access discriminant.
4300
4301 if Ekind (Typ) /= E_Anonymous_Access_Type
4302 or else Is_Local_Anonymous_Access (Typ)
4303 then
4304 Subtyp := Entity (Subtype_Mark (E));
4305
4306 Aggr := Original_Node (Expression (E));
4307
4308 if Has_Discriminants (Subtyp)
45fc7ddb 4309 and then Nkind_In (Aggr, N_Aggregate, N_Extension_Aggregate)
b7d1f17f
HK		 4310 then
4311 Discrim := First_Discriminant (Base_Type (Subtyp));
4312
4313 -- Get the first component expression of the aggregate
4314
4315 if Present (Expressions (Aggr)) then
4316 Disc_Exp := First (Expressions (Aggr));
4317
4318 elsif Present (Component_Associations (Aggr)) then
4319 Assoc := First (Component_Associations (Aggr));
4320
4321 if Present (Assoc) then
4322 Disc_Exp := Expression (Assoc);
4323 else
4324 Disc_Exp := Empty;
4325 end if;
4326
4327 else
4328 Disc_Exp := Empty;
4329 end if;
4330
4331 while Present (Discrim) and then Present (Disc_Exp) loop
4332 if Ekind (Etype (Discrim)) = E_Anonymous_Access_Type then
4333 Check_Allocator_Discrim_Accessibility (Disc_Exp, Typ);
4334 end if;
4335
4336 Next_Discriminant (Discrim);
4337
4338 if Present (Discrim) then
4339 if Present (Assoc) then
4340 Next (Assoc);
4341 Disc_Exp := Expression (Assoc);
4342
4343 elsif Present (Next (Disc_Exp)) then
4344 Next (Disc_Exp);
4345
4346 else
4347 Assoc := First (Component_Associations (Aggr));
4348
4349 if Present (Assoc) then
4350 Disc_Exp := Expression (Assoc);
4351 else
4352 Disc_Exp := Empty;
4353 end if;
4354 end if;
4355 end if;
4356 end loop;
4357 end if;
4358 end if;
4359
996ae0b0
RK		 4360 -- For a subtype mark or subtype indication, freeze the subtype
4361
4362 else
4363 Freeze_Expression (E);
4364
4365 if Is_Access_Constant (Typ) and then not No_Initialization (N) then
4366 Error_Msg_N
4367 ("initialization required for access-to-constant allocator", N);
4368 end if;
4369
4370 -- A special accessibility check is needed for allocators that
4371 -- constrain access discriminants. The level of the type of the
b7d1f17f 4372 -- expression used to constrain an access discriminant cannot be
f3d57416 4373 -- deeper than the type of the allocator (in contrast to access
996ae0b0
RK		 4374 -- parameters, where the level of the actual can be arbitrary).
4375 -- We can't use Valid_Conversion to perform this check because
4376 -- in general the type of the allocator is unrelated to the type
b7d1f17f 4377 -- of the access discriminant.
996ae0b0
RK		 4378
4379 if Nkind (Original_Node (E)) = N_Subtype_Indication
b7d1f17f
HK		 4380 and then (Ekind (Typ) /= E_Anonymous_Access_Type
4381 or else Is_Local_Anonymous_Access (Typ))
996ae0b0
RK		 4382 then
4383 Subtyp := Entity (Subtype_Mark (Original_Node (E)));
4384
4385 if Has_Discriminants (Subtyp) then
4386 Discrim := First_Discriminant (Base_Type (Subtyp));
4387 Constr := First (Constraints (Constraint (Original_Node (E))));
996ae0b0
RK		 4388 while Present (Discrim) and then Present (Constr) loop
4389 if Ekind (Etype (Discrim)) = E_Anonymous_Access_Type then
4390 if Nkind (Constr) = N_Discriminant_Association then
4391 Disc_Exp := Original_Node (Expression (Constr));
4392 else
4393 Disc_Exp := Original_Node (Constr);
4394 end if;
4395
b7d1f17f 4396 Check_Allocator_Discrim_Accessibility (Disc_Exp, Typ);
996ae0b0 4397 end if;
b7d1f17f 4398
996ae0b0
RK		 4399 Next_Discriminant (Discrim);
4400 Next (Constr);
4401 end loop;
4402 end if;
4403 end if;
4404 end if;
4405
758c442c
GD		 4406 -- Ada 2005 (AI-344): A class-wide allocator requires an accessibility
4407 -- check that the level of the type of the created object is not deeper
4408 -- than the level of the allocator's access type, since extensions can
4409 -- now occur at deeper levels than their ancestor types. This is a
4410 -- static accessibility level check; a run-time check is also needed in
4411 -- the case of an initialized allocator with a class-wide argument (see
4412 -- Expand_Allocator_Expression).
4413
0791fbe9 4414 if Ada_Version >= Ada_2005
949a18cc 4415 and then Is_Class_Wide_Type (Desig_T)
758c442c
GD		 4416 then
4417 declare
b7d1f17f 4418 Exp_Typ : Entity_Id;
758c442c
GD		 4419
4420 begin
4421 if Nkind (E) = N_Qualified_Expression then
4422 Exp_Typ := Etype (E);
4423 elsif Nkind (E) = N_Subtype_Indication then
4424 Exp_Typ := Entity (Subtype_Mark (Original_Node (E)));
4425 else
4426 Exp_Typ := Entity (E);
4427 end if;
4428
f460d8f3 4429 if Type_Access_Level (Exp_Typ) >
83e5da69
AC		 4430 Deepest_Type_Access_Level (Typ)
4431 then
758c442c
GD		 4432 if In_Instance_Body then
4433 Error_Msg_N ("?type in allocator has deeper level than" &
4434 " designated class-wide type", E);
c8ef728f
ES		 4435 Error_Msg_N ("\?Program_Error will be raised at run time",
4436 E);
758c442c
GD		 4437 Rewrite (N,
4438 Make_Raise_Program_Error (Sloc (N),
4439 Reason => PE_Accessibility_Check_Failed));
4440 Set_Etype (N, Typ);
aa180613
RD		 4441
4442 -- Do not apply Ada 2005 accessibility checks on a class-wide
4443 -- allocator if the type given in the allocator is a formal
4444 -- type. A run-time check will be performed in the instance.
4445
4446 elsif not Is_Generic_Type (Exp_Typ) then
758c442c
GD		 4447 Error_Msg_N ("type in allocator has deeper level than" &
4448 " designated class-wide type", E);
4449 end if;
4450 end if;
4451 end;
4452 end if;
4453
996ae0b0
RK		 4454 -- Check for allocation from an empty storage pool
4455
4456 if No_Pool_Assigned (Typ) then
8da337c5 4457 Error_Msg_N ("allocation from empty storage pool!", N);
1420b484 4458
5cc9353d
RD		 4459 -- If the context is an unchecked conversion, as may happen within an
4460 -- inlined subprogram, the allocator is being resolved with its own
4461 -- anonymous type. In that case, if the target type has a specific
1420b484
JM		 4462 -- storage pool, it must be inherited explicitly by the allocator type.
4463
4464 elsif Nkind (Parent (N)) = N_Unchecked_Type_Conversion
4465 and then No (Associated_Storage_Pool (Typ))
4466 then
4467 Set_Associated_Storage_Pool
4468 (Typ, Associated_Storage_Pool (Etype (Parent (N))));
996ae0b0 4469 end if;
b7d1f17f 4470
e57ab550
AC		 4471 if Ekind (Etype (N)) = E_Anonymous_Access_Type then
4472 Check_Restriction (No_Anonymous_Allocators, N);
4473 end if;
4474
6aaa0587
ES		 4475 -- Check that an allocator with task parts isn't for a nested access
4476 -- type when restriction No_Task_Hierarchy applies.
4477
4478 if not Is_Library_Level_Entity (Base_Type (Typ))
949a18cc 4479 and then Has_Task (Base_Type (Desig_T))
6aaa0587
ES		 4480 then
4481 Check_Restriction (No_Task_Hierarchy, N);
4482 end if;
4483
b7d1f17f
HK		 4484 -- An erroneous allocator may be rewritten as a raise Program_Error
4485 -- statement.
4486
4487 if Nkind (N) = N_Allocator then
4488
4489 -- An anonymous access discriminant is the definition of a
aa5147f0 4490 -- coextension.
b7d1f17f
HK		 4491
4492 if Ekind (Typ) = E_Anonymous_Access_Type
4493 and then Nkind (Associated_Node_For_Itype (Typ)) =
4494 N_Discriminant_Specification
4495 then
949a18cc
AC		 4496 declare
4497 Discr : constant Entity_Id :=
4498 Defining_Identifier (Associated_Node_For_Itype (Typ));
ee2e3f6b 4499
949a18cc 4500 begin
5d59eef2
AC		 4501 -- Ada 2012 AI05-0052: If the designated type of the allocator
4502 -- is limited, then the allocator shall not be used to define
4503 -- the value of an access discriminant unless the discriminated
949a18cc
AC		 4504 -- type is immutably limited.
4505
4506 if Ada_Version >= Ada_2012
4507 and then Is_Limited_Type (Desig_T)
4508 and then not Is_Immutably_Limited_Type (Scope (Discr))
4509 then
4510 Error_Msg_N
5d59eef2
AC		 4511 ("only immutably limited types can have anonymous "
4512 & "access discriminants designating a limited type", N);
949a18cc
AC		 4513 end if;
4514 end;
4515
b7d1f17f 4516 -- Avoid marking an allocator as a dynamic coextension if it is
aa5147f0 4517 -- within a static construct.
b7d1f17f
HK		 4518
4519 if not Is_Static_Coextension (N) then
aa5147f0 4520 Set_Is_Dynamic_Coextension (N);
b7d1f17f
HK		 4521 end if;
4522
4523 -- Cleanup for potential static coextensions
4524
4525 else
aa5147f0
ES		 4526 Set_Is_Dynamic_Coextension (N, False);
4527 Set_Is_Static_Coextension (N, False);
b7d1f17f 4528 end if;
b7d1f17f 4529 end if;
d9b056ea 4530
833eaa8a 4531 -- Report a simple error: if the designated object is a local task,
14848f57
AC		 4532 -- its body has not been seen yet, and its activation will fail an
4533 -- elaboration check.
d9b056ea 4534
949a18cc
AC		 4535 if Is_Task_Type (Desig_T)
4536 and then Scope (Base_Type (Desig_T)) = Current_Scope
d9b056ea
AC		 4537 and then Is_Compilation_Unit (Current_Scope)
4538 and then Ekind (Current_Scope) = E_Package
4539 and then not In_Package_Body (Current_Scope)
4540 then
7b2aafc9
HK		 4541 Error_Msg_N ("?cannot activate task before body seen", N);
4542 Error_Msg_N ("\?Program_Error will be raised at run time", N);
d9b056ea 4543 end if;
14848f57 4544
7b2aafc9
HK		 4545 -- Ada 2012 (AI05-0111-3): Detect an attempt to allocate a task or a
4546 -- type with a task component on a subpool. This action must raise
4547 -- Program_Error at runtime.
14848f57
AC		 4548
4549 if Ada_Version >= Ada_2012
dfbcb149 4550 and then Nkind (N) = N_Allocator
14848f57
AC		 4551 and then Present (Subpool_Handle_Name (N))
4552 and then Has_Task (Desig_T)
4553 then
7b2aafc9
HK		 4554 Error_Msg_N ("?cannot allocate task on subpool", N);
4555 Error_Msg_N ("\?Program_Error will be raised at run time", N);
4556
4557 Rewrite (N,
4558 Make_Raise_Program_Error (Sloc (N),
4559 Reason => PE_Explicit_Raise));
4560 Set_Etype (N, Typ);
14848f57 4561 end if;
996ae0b0
RK		 4562 end Resolve_Allocator;
4563
4564 ---------------------------
4565 -- Resolve_Arithmetic_Op --
4566 ---------------------------
4567
4568 -- Used for resolving all arithmetic operators except exponentiation
4569
4570 procedure Resolve_Arithmetic_Op (N : Node_Id; Typ : Entity_Id) is
fbf5a39b
AC		 4571 L : constant Node_Id := Left_Opnd (N);
4572 R : constant Node_Id := Right_Opnd (N);
4573 TL : constant Entity_Id := Base_Type (Etype (L));
4574 TR : constant Entity_Id := Base_Type (Etype (R));
4575 T : Entity_Id;
4576 Rop : Node_Id;
996ae0b0
RK		 4577
4578 B_Typ : constant Entity_Id := Base_Type (Typ);
4579 -- We do the resolution using the base type, because intermediate values
4580 -- in expressions always are of the base type, not a subtype of it.
4581
aa180613
RD		 4582 function Expected_Type_Is_Any_Real (N : Node_Id) return Boolean;
4583 -- Returns True if N is in a context that expects "any real type"
4584
996ae0b0
RK		 4585 function Is_Integer_Or_Universal (N : Node_Id) return Boolean;
4586 -- Return True iff given type is Integer or universal real/integer
4587
4588 procedure Set_Mixed_Mode_Operand (N : Node_Id; T : Entity_Id);
4589 -- Choose type of integer literal in fixed-point operation to conform
4590 -- to available fixed-point type. T is the type of the other operand,
4591 -- which is needed to determine the expected type of N.
4592
4593 procedure Set_Operand_Type (N : Node_Id);
4594 -- Set operand type to T if universal
4595
aa180613
RD		 4596 -------------------------------
4597 -- Expected_Type_Is_Any_Real --
4598 -------------------------------
4599
4600 function Expected_Type_Is_Any_Real (N : Node_Id) return Boolean is
4601 begin
4602 -- N is the expression after "delta" in a fixed_point_definition;
4603 -- see RM-3.5.9(6):
4604
45fc7ddb
HK		 4605 return Nkind_In (Parent (N), N_Ordinary_Fixed_Point_Definition,
4606 N_Decimal_Fixed_Point_Definition,
aa180613
RD		 4607
4608 -- N is one of the bounds in a real_range_specification;
4609 -- see RM-3.5.7(5):
4610
45fc7ddb 4611 N_Real_Range_Specification,
aa180613
RD		 4612
4613 -- N is the expression of a delta_constraint;
4614 -- see RM-J.3(3):
4615
45fc7ddb 4616 N_Delta_Constraint);
aa180613
RD		 4617 end Expected_Type_Is_Any_Real;
4618
996ae0b0
RK		 4619 -----------------------------
4620 -- Is_Integer_Or_Universal --
4621 -----------------------------
4622
4623 function Is_Integer_Or_Universal (N : Node_Id) return Boolean is
4624 T : Entity_Id;
4625 Index : Interp_Index;
4626 It : Interp;
4627
4628 begin
4629 if not Is_Overloaded (N) then
4630 T := Etype (N);
4631 return Base_Type (T) = Base_Type (Standard_Integer)
4632 or else T = Universal_Integer
4633 or else T = Universal_Real;
4634 else
4635 Get_First_Interp (N, Index, It);
996ae0b0 4636 while Present (It.Typ) loop
996ae0b0
RK		 4637 if Base_Type (It.Typ) = Base_Type (Standard_Integer)
4638 or else It.Typ = Universal_Integer
4639 or else It.Typ = Universal_Real
4640 then
4641 return True;
4642 end if;
4643
4644 Get_Next_Interp (Index, It);
4645 end loop;
4646 end if;
4647
4648 return False;
4649 end Is_Integer_Or_Universal;
4650
4651 ----------------------------
4652 -- Set_Mixed_Mode_Operand --
4653 ----------------------------
4654
4655 procedure Set_Mixed_Mode_Operand (N : Node_Id; T : Entity_Id) is
4656 Index : Interp_Index;
4657 It : Interp;
4658
4659 begin
4660 if Universal_Interpretation (N) = Universal_Integer then
4661
4662 -- A universal integer literal is resolved as standard integer
758c442c
GD		 4663 -- except in the case of a fixed-point result, where we leave it
4664 -- as universal (to be handled by Exp_Fixd later on)
996ae0b0
RK		 4665
4666 if Is_Fixed_Point_Type (T) then
4667 Resolve (N, Universal_Integer);
4668 else
4669 Resolve (N, Standard_Integer);
4670 end if;
4671
4672 elsif Universal_Interpretation (N) = Universal_Real
4673 and then (T = Base_Type (Standard_Integer)
4674 or else T = Universal_Integer
4675 or else T = Universal_Real)
4676 then
4677 -- A universal real can appear in a fixed-type context. We resolve
4678 -- the literal with that context, even though this might raise an
4679 -- exception prematurely (the other operand may be zero).
4680
4681 Resolve (N, B_Typ);
4682
4683 elsif Etype (N) = Base_Type (Standard_Integer)
4684 and then T = Universal_Real
4685 and then Is_Overloaded (N)
4686 then
4687 -- Integer arg in mixed-mode operation. Resolve with universal
4688 -- type, in case preference rule must be applied.
4689
4690 Resolve (N, Universal_Integer);
4691
4692 elsif Etype (N) = T
4693 and then B_Typ /= Universal_Fixed
4694 then
a77842bd 4695 -- Not a mixed-mode operation, resolve with context
996ae0b0
RK		 4696
4697 Resolve (N, B_Typ);
4698
4699 elsif Etype (N) = Any_Fixed then
4700
a77842bd 4701 -- N may itself be a mixed-mode operation, so use context type
996ae0b0
RK		 4702
4703 Resolve (N, B_Typ);
4704
4705 elsif Is_Fixed_Point_Type (T)
4706 and then B_Typ = Universal_Fixed
4707 and then Is_Overloaded (N)
4708 then
4709 -- Must be (fixed * fixed) operation, operand must have one
4710 -- compatible interpretation.
4711
4712 Resolve (N, Any_Fixed);
4713
4714 elsif Is_Fixed_Point_Type (B_Typ)
4715 and then (T = Universal_Real
4716 or else Is_Fixed_Point_Type (T))
4717 and then Is_Overloaded (N)
4718 then
4719 -- C * F(X) in a fixed context, where C is a real literal or a
4720 -- fixed-point expression. F must have either a fixed type
4721 -- interpretation or an integer interpretation, but not both.
4722
4723 Get_First_Interp (N, Index, It);
996ae0b0 4724 while Present (It.Typ) loop
996ae0b0 4725 if Base_Type (It.Typ) = Base_Type (Standard_Integer) then
996ae0b0
RK		 4726 if Analyzed (N) then
4727 Error_Msg_N ("ambiguous operand in fixed operation", N);
4728 else
4729 Resolve (N, Standard_Integer);
4730 end if;
4731
4732 elsif Is_Fixed_Point_Type (It.Typ) then
996ae0b0
RK		 4733 if Analyzed (N) then
4734 Error_Msg_N ("ambiguous operand in fixed operation", N);
4735 else
4736 Resolve (N, It.Typ);
4737 end if;
4738 end if;
4739
4740 Get_Next_Interp (Index, It);
4741 end loop;
4742
758c442c
GD		 4743 -- Reanalyze the literal with the fixed type of the context. If
4744 -- context is Universal_Fixed, we are within a conversion, leave
4745 -- the literal as a universal real because there is no usable
4746 -- fixed type, and the target of the conversion plays no role in
4747 -- the resolution.
996ae0b0 4748
0ab80019
AC		 4749 declare
4750 Op2 : Node_Id;
4751 T2 : Entity_Id;
4752
4753 begin
4754 if N = L then
4755 Op2 := R;
4756 else
4757 Op2 := L;
4758 end if;
4759
4760 if B_Typ = Universal_Fixed
4761 and then Nkind (Op2) = N_Real_Literal
4762 then
4763 T2 := Universal_Real;
4764 else
4765 T2 := B_Typ;
4766 end if;
4767
4768 Set_Analyzed (Op2, False);
4769 Resolve (Op2, T2);
4770 end;
996ae0b0
RK		 4771
4772 else
fbf5a39b 4773 Resolve (N);
996ae0b0
RK		 4774 end if;
4775 end Set_Mixed_Mode_Operand;
4776
4777 ----------------------
4778 -- Set_Operand_Type --
4779 ----------------------
4780
4781 procedure Set_Operand_Type (N : Node_Id) is
4782 begin
4783 if Etype (N) = Universal_Integer
4784 or else Etype (N) = Universal_Real
4785 then
4786 Set_Etype (N, T);
4787 end if;
4788 end Set_Operand_Type;
4789
996ae0b0
RK		 4790 -- Start of processing for Resolve_Arithmetic_Op
4791
4792 begin
4793 if Comes_From_Source (N)
4794 and then Ekind (Entity (N)) = E_Function
4795 and then Is_Imported (Entity (N))
fbf5a39b 4796 and then Is_Intrinsic_Subprogram (Entity (N))
996ae0b0
RK		 4797 then
4798 Resolve_Intrinsic_Operator (N, Typ);
4799 return;
4800
5cc9353d
RD		 4801 -- Special-case for mixed-mode universal expressions or fixed point type
4802 -- operation: each argument is resolved separately. The same treatment
4803 -- is required if one of the operands of a fixed point operation is
4804 -- universal real, since in this case we don't do a conversion to a
4805 -- specific fixed-point type (instead the expander handles the case).
996ae0b0 4806
ddf67a1d
AC		 4807 -- Set the type of the node to its universal interpretation because
4808 -- legality checks on an exponentiation operand need the context.
4809
45fc7ddb 4810 elsif (B_Typ = Universal_Integer or else B_Typ = Universal_Real)
996ae0b0
RK		 4811 and then Present (Universal_Interpretation (L))
4812 and then Present (Universal_Interpretation (R))
4813 then
ddf67a1d 4814 Set_Etype (N, B_Typ);
996ae0b0
RK		 4815 Resolve (L, Universal_Interpretation (L));
4816 Resolve (R, Universal_Interpretation (R));
996ae0b0
RK		 4817
4818 elsif (B_Typ = Universal_Real
45fc7ddb
HK		 4819 or else Etype (N) = Universal_Fixed
4820 or else (Etype (N) = Any_Fixed
4821 and then Is_Fixed_Point_Type (B_Typ))
4822 or else (Is_Fixed_Point_Type (B_Typ)
4823 and then (Is_Integer_Or_Universal (L)
4824 or else
4825 Is_Integer_Or_Universal (R))))
4826 and then Nkind_In (N, N_Op_Multiply, N_Op_Divide)
996ae0b0
RK		 4827 then
4828 if TL = Universal_Integer or else TR = Universal_Integer then
4829 Check_For_Visible_Operator (N, B_Typ);
4830 end if;
4831
5cc9353d
RD		 4832 -- If context is a fixed type and one operand is integer, the other
4833 -- is resolved with the type of the context.
996ae0b0
RK		 4834
4835 if Is_Fixed_Point_Type (B_Typ)
4836 and then (Base_Type (TL) = Base_Type (Standard_Integer)
4837 or else TL = Universal_Integer)
4838 then
4839 Resolve (R, B_Typ);
4840 Resolve (L, TL);
4841
4842 elsif Is_Fixed_Point_Type (B_Typ)
4843 and then (Base_Type (TR) = Base_Type (Standard_Integer)
4844 or else TR = Universal_Integer)
4845 then
4846 Resolve (L, B_Typ);
4847 Resolve (R, TR);
4848
4849 else
4850 Set_Mixed_Mode_Operand (L, TR);
4851 Set_Mixed_Mode_Operand (R, TL);
4852 end if;
4853
45fc7ddb
HK		 4854 -- Check the rule in RM05-4.5.5(19.1/2) disallowing universal_fixed
4855 -- multiplying operators from being used when the expected type is
4856 -- also universal_fixed. Note that B_Typ will be Universal_Fixed in
4857 -- some cases where the expected type is actually Any_Real;
4858 -- Expected_Type_Is_Any_Real takes care of that case.
aa180613 4859
996ae0b0
RK		 4860 if Etype (N) = Universal_Fixed
4861 or else Etype (N) = Any_Fixed
4862 then
4863 if B_Typ = Universal_Fixed
aa180613 4864 and then not Expected_Type_Is_Any_Real (N)
45fc7ddb
HK		 4865 and then not Nkind_In (Parent (N), N_Type_Conversion,
4866 N_Unchecked_Type_Conversion)
996ae0b0 4867 then
45fc7ddb
HK		 4868 Error_Msg_N ("type cannot be determined from context!", N);
4869 Error_Msg_N ("\explicit conversion to result type required", N);
996ae0b0
RK		 4870
4871 Set_Etype (L, Any_Type);
4872 Set_Etype (R, Any_Type);
4873
4874 else
0ab80019 4875 if Ada_Version = Ada_83
45fc7ddb
HK		 4876 and then Etype (N) = Universal_Fixed
4877 and then not
4878 Nkind_In (Parent (N), N_Type_Conversion,
4879 N_Unchecked_Type_Conversion)
996ae0b0
RK		 4880 then
4881 Error_Msg_N
45fc7ddb
HK		 4882 ("(Ada 83) fixed-point operation "
4883 & "needs explicit conversion", N);
996ae0b0
RK		 4884 end if;
4885
aa180613 4886 -- The expected type is "any real type" in contexts like
5cc9353d 4887
aa180613 4888 -- type T is delta <universal_fixed-expression> ...
5cc9353d 4889
aa180613
RD		 4890 -- in which case we need to set the type to Universal_Real
4891 -- so that static expression evaluation will work properly.
4892
4893 if Expected_Type_Is_Any_Real (N) then
4894 Set_Etype (N, Universal_Real);
4895 else
4896 Set_Etype (N, B_Typ);
4897 end if;
996ae0b0
RK		 4898 end if;
4899
4900 elsif Is_Fixed_Point_Type (B_Typ)
4901 and then (Is_Integer_Or_Universal (L)
4902 or else Nkind (L) = N_Real_Literal
4903 or else Nkind (R) = N_Real_Literal
45fc7ddb 4904 or else Is_Integer_Or_Universal (R))
996ae0b0
RK		 4905 then
4906 Set_Etype (N, B_Typ);
4907
4908 elsif Etype (N) = Any_Fixed then
4909
5cc9353d
RD		 4910 -- If no previous errors, this is only possible if one operand is
4911 -- overloaded and the context is universal. Resolve as such.
996ae0b0
RK		 4912
4913 Set_Etype (N, B_Typ);
4914 end if;
4915
4916 else
4917 if (TL = Universal_Integer or else TL = Universal_Real)
45fc7ddb
HK		 4918 and then
4919 (TR = Universal_Integer or else TR = Universal_Real)
996ae0b0
RK		 4920 then
4921 Check_For_Visible_Operator (N, B_Typ);
4922 end if;
4923
4924 -- If the context is Universal_Fixed and the operands are also
4925 -- universal fixed, this is an error, unless there is only one
841dd0f5 4926 -- applicable fixed_point type (usually Duration).
996ae0b0 4927
45fc7ddb 4928 if B_Typ = Universal_Fixed and then Etype (L) = Universal_Fixed then
996ae0b0
RK		 4929 T := Unique_Fixed_Point_Type (N);
4930
4931 if T = Any_Type then
4932 Set_Etype (N, T);
4933 return;
4934 else
4935 Resolve (L, T);
4936 Resolve (R, T);
4937 end if;
4938
4939 else
4940 Resolve (L, B_Typ);
4941 Resolve (R, B_Typ);
4942 end if;
4943
4944 -- If one of the arguments was resolved to a non-universal type.
4945 -- label the result of the operation itself with the same type.
4946 -- Do the same for the universal argument, if any.
4947
4948 T := Intersect_Types (L, R);
4949 Set_Etype (N, Base_Type (T));
4950 Set_Operand_Type (L);
4951 Set_Operand_Type (R);
4952 end if;
4953
fbf5a39b 4954 Generate_Operator_Reference (N, Typ);
dec6faf1 4955 Analyze_Dimension (N);
996ae0b0
RK		 4956 Eval_Arithmetic_Op (N);
4957
2ba431e5
YM		 4958 -- In SPARK, a multiplication or division with operands of fixed point
4959 -- types shall be qualified or explicitly converted to identify the
4960 -- result type.
b0186f71 4961
fe5d3068
YM		 4962 if (Is_Fixed_Point_Type (Etype (L))
4963 or else Is_Fixed_Point_Type (Etype (R)))
b0186f71
AC		 4964 and then Nkind_In (N, N_Op_Multiply, N_Op_Divide)
4965 and then
4966 not Nkind_In (Parent (N), N_Qualified_Expression, N_Type_Conversion)
4967 then
2ba431e5 4968 Check_SPARK_Restriction
fe5d3068 4969 ("operation should be qualified or explicitly converted", N);
b0186f71
AC		 4970 end if;
4971
996ae0b0
RK		 4972 -- Set overflow and division checking bit. Much cleverer code needed
4973 -- here eventually and perhaps the Resolve routines should be separated
4974 -- for the various arithmetic operations, since they will need
4975 -- different processing. ???
4976
4977 if Nkind (N) in N_Op then
4978 if not Overflow_Checks_Suppressed (Etype (N)) then
fbf5a39b 4979 Enable_Overflow_Check (N);
996ae0b0
RK		 4980 end if;
4981
fbf5a39b
AC		 4982 -- Give warning if explicit division by zero
4983
45fc7ddb 4984 if Nkind_In (N, N_Op_Divide, N_Op_Rem, N_Op_Mod)
996ae0b0
RK		 4985 and then not Division_Checks_Suppressed (Etype (N))
4986 then
fbf5a39b
AC		 4987 Rop := Right_Opnd (N);
4988
4989 if Compile_Time_Known_Value (Rop)
4990 and then ((Is_Integer_Type (Etype (Rop))
780d052e
RD		 4991 and then Expr_Value (Rop) = Uint_0)
4992 or else
4993 (Is_Real_Type (Etype (Rop))
4994 and then Expr_Value_R (Rop) = Ureal_0))
fbf5a39b 4995 then
ce72a9a3
AC		 4996 -- Specialize the warning message according to the operation.
4997 -- The following warnings are for the case
aa180613
RD		 4998
4999 case Nkind (N) is
5000 when N_Op_Divide =>
ce72a9a3
AC		 5001
5002 -- For division, we have two cases, for float division
5003 -- of an unconstrained float type, on a machine where
5004 -- Machine_Overflows is false, we don't get an exception
5005 -- at run-time, but rather an infinity or Nan. The Nan
5006 -- case is pretty obscure, so just warn about infinities.
5007
5008 if Is_Floating_Point_Type (Typ)
5009 and then not Is_Constrained (Typ)
5010 and then not Machine_Overflows_On_Target
5011 then
5012 Error_Msg_N
5013 ("float division by zero, " &
5014 "may generate '+'/'- infinity?", Right_Opnd (N));
5015
5016 -- For all other cases, we get a Constraint_Error
5017
5018 else
5019 Apply_Compile_Time_Constraint_Error
5020 (N, "division by zero?", CE_Divide_By_Zero,
5021 Loc => Sloc (Right_Opnd (N)));
5022 end if;
aa180613
RD		 5023
5024 when N_Op_Rem =>
5025 Apply_Compile_Time_Constraint_Error
5026 (N, "rem with zero divisor?", CE_Divide_By_Zero,
5027 Loc => Sloc (Right_Opnd (N)));
5028
5029 when N_Op_Mod =>
5030 Apply_Compile_Time_Constraint_Error
5031 (N, "mod with zero divisor?", CE_Divide_By_Zero,
5032 Loc => Sloc (Right_Opnd (N)));
5033
5034 -- Division by zero can only happen with division, rem,
5035 -- and mod operations.
5036
5037 when others =>
5038 raise Program_Error;
5039 end case;
fbf5a39b
AC		 5040
5041 -- Otherwise just set the flag to check at run time
5042
5043 else
b7d1f17f 5044 Activate_Division_Check (N);
fbf5a39b 5045 end if;
996ae0b0 5046 end if;
45fc7ddb
HK		 5047
5048 -- If Restriction No_Implicit_Conditionals is active, then it is
5049 -- violated if either operand can be negative for mod, or for rem
5050 -- if both operands can be negative.
5051
7a963087 5052 if Restriction_Check_Required (No_Implicit_Conditionals)
45fc7ddb
HK		 5053 and then Nkind_In (N, N_Op_Rem, N_Op_Mod)
5054 then
5055 declare
5056 Lo : Uint;
5057 Hi : Uint;
5058 OK : Boolean;
5059
5060 LNeg : Boolean;
5061 RNeg : Boolean;
5062 -- Set if corresponding operand might be negative
5063
5064 begin
5d5e9775
AC		 5065 Determine_Range
5066 (Left_Opnd (N), OK, Lo, Hi, Assume_Valid => True);
45fc7ddb
HK		 5067 LNeg := (not OK) or else Lo < 0;
5068
5d5e9775
AC		 5069 Determine_Range
5070 (Right_Opnd (N), OK, Lo, Hi, Assume_Valid => True);
45fc7ddb
HK		 5071 RNeg := (not OK) or else Lo < 0;
5072
5d5e9775
AC		 5073 -- Check if we will be generating conditionals. There are two
5074 -- cases where that can happen, first for REM, the only case
5075 -- is largest negative integer mod -1, where the division can
5076 -- overflow, but we still have to give the right result. The
5077 -- front end generates a test for this annoying case. Here we
5078 -- just test if both operands can be negative (that's what the
5079 -- expander does, so we match its logic here).
5080
5081 -- The second case is mod where either operand can be negative.
308e6f3a 5082 -- In this case, the back end has to generate additional tests.
5d5e9775 5083
45fc7ddb
HK		 5084 if (Nkind (N) = N_Op_Rem and then (LNeg and RNeg))
5085 or else
5086 (Nkind (N) = N_Op_Mod and then (LNeg or RNeg))
5087 then
5088 Check_Restriction (No_Implicit_Conditionals, N);
5089 end if;
5090 end;
5091 end if;
996ae0b0
RK		 5092 end if;
5093
5094 Check_Unset_Reference (L);
5095 Check_Unset_Reference (R);
996ae0b0
RK		 5096 end Resolve_Arithmetic_Op;
5097
5098 ------------------
5099 -- Resolve_Call --
5100 ------------------
5101
5102 procedure Resolve_Call (N : Node_Id; Typ : Entity_Id) is
5103 Loc : constant Source_Ptr := Sloc (N);
5104 Subp : constant Node_Id := Name (N);
5105 Nam : Entity_Id;
5106 I : Interp_Index;
5107 It : Interp;
5108 Norm_OK : Boolean;
5109 Scop : Entity_Id;
aa180613 5110 Rtype : Entity_Id;
996ae0b0 5111
ee81cbe9
AC		 5112 function Same_Or_Aliased_Subprograms
5113 (S : Entity_Id;
5114 E : Entity_Id) return Boolean;
5115 -- Returns True if the subprogram entity S is the same as E or else
5116 -- S is an alias of E.
5117
001c7783
AC		 5118 ---------------------------------
5119 -- Same_Or_Aliased_Subprograms --
5120 ---------------------------------
5121
ee81cbe9
AC		 5122 function Same_Or_Aliased_Subprograms
5123 (S : Entity_Id;
5124 E : Entity_Id) return Boolean
5125 is
5126 Subp_Alias : constant Entity_Id := Alias (S);
ee81cbe9
AC		 5127 begin
5128 return S = E
5129 or else (Present (Subp_Alias) and then Subp_Alias = E);
5130 end Same_Or_Aliased_Subprograms;
5131
5132 -- Start of processing for Resolve_Call
5133
996ae0b0 5134 begin
758c442c
GD		 5135 -- The context imposes a unique interpretation with type Typ on a
5136 -- procedure or function call. Find the entity of the subprogram that
5137 -- yields the expected type, and propagate the corresponding formal
5138 -- constraints on the actuals. The caller has established that an
5139 -- interpretation exists, and emitted an error if not unique.
996ae0b0
RK		 5140
5141 -- First deal with the case of a call to an access-to-subprogram,
5142 -- dereference made explicit in Analyze_Call.
5143
5144 if Ekind (Etype (Subp)) = E_Subprogram_Type then
996ae0b0
RK		 5145 if not Is_Overloaded (Subp) then
5146 Nam := Etype (Subp);
5147
5148 else
758c442c
GD		 5149 -- Find the interpretation whose type (a subprogram type) has a
5150 -- return type that is compatible with the context. Analysis of
5151 -- the node has established that one exists.
996ae0b0 5152
996ae0b0
RK		 5153 Nam := Empty;
5154
1420b484 5155 Get_First_Interp (Subp, I, It);
996ae0b0 5156 while Present (It.Typ) loop
996ae0b0
RK		 5157 if Covers (Typ, Etype (It.Typ)) then
5158 Nam := It.Typ;
5159 exit;
5160 end if;
5161
5162 Get_Next_Interp (I, It);
5163 end loop;
5164
5165 if No (Nam) then
5166 raise Program_Error;
5167 end if;
5168 end if;
5169
5170 -- If the prefix is not an entity, then resolve it
5171
5172 if not Is_Entity_Name (Subp) then
5173 Resolve (Subp, Nam);
5174 end if;
5175
758c442c
GD		 5176 -- For an indirect call, we always invalidate checks, since we do not
5177 -- know whether the subprogram is local or global. Yes we could do
5178 -- better here, e.g. by knowing that there are no local subprograms,
aa180613 5179 -- but it does not seem worth the effort. Similarly, we kill all
758c442c 5180 -- knowledge of current constant values.
fbf5a39b
AC		 5181
5182 Kill_Current_Values;
5183
b7d1f17f
HK		 5184 -- If this is a procedure call which is really an entry call, do
5185 -- the conversion of the procedure call to an entry call. Protected
5186 -- operations use the same circuitry because the name in the call
5187 -- can be an arbitrary expression with special resolution rules.
996ae0b0 5188
45fc7ddb 5189 elsif Nkind_In (Subp, N_Selected_Component, N_Indexed_Component)
996ae0b0
RK		 5190 or else (Is_Entity_Name (Subp)
5191 and then Ekind (Entity (Subp)) = E_Entry)
5192 then
5193 Resolve_Entry_Call (N, Typ);
5194 Check_Elab_Call (N);
fbf5a39b
AC		 5195
5196 -- Kill checks and constant values, as above for indirect case
5197 -- Who knows what happens when another task is activated?
5198
5199 Kill_Current_Values;
996ae0b0
RK		 5200 return;
5201
5202 -- Normal subprogram call with name established in Resolve
5203
5204 elsif not (Is_Type (Entity (Subp))) then
5205 Nam := Entity (Subp);
5206 Set_Entity_With_Style_Check (Subp, Nam);
996ae0b0
RK		 5207
5208 -- Otherwise we must have the case of an overloaded call
5209
5210 else
5211 pragma Assert (Is_Overloaded (Subp));
d81b4bfe
TQ		 5212
5213 -- Initialize Nam to prevent warning (we know it will be assigned
5214 -- in the loop below, but the compiler does not know that).
5215
5216 Nam := Empty;
996ae0b0
RK		 5217
5218 Get_First_Interp (Subp, I, It);
996ae0b0
RK		 5219 while Present (It.Typ) loop
5220 if Covers (Typ, It.Typ) then
5221 Nam := It.Nam;
5222 Set_Entity_With_Style_Check (Subp, Nam);
996ae0b0
RK		 5223 exit;
5224 end if;
5225
5226 Get_Next_Interp (I, It);
5227 end loop;
5228 end if;
5229
c9b99571
ES		 5230 if Is_Access_Subprogram_Type (Base_Type (Etype (Nam)))
5231 and then not Is_Access_Subprogram_Type (Base_Type (Typ))
53cf4600
ES		 5232 and then Nkind (Subp) /= N_Explicit_Dereference
5233 and then Present (Parameter_Associations (N))
5234 then
66aa7643
TQ		 5235 -- The prefix is a parameterless function call that returns an access
5236 -- to subprogram. If parameters are present in the current call, add
5237 -- add an explicit dereference. We use the base type here because
5238 -- within an instance these may be subtypes.
53cf4600
ES		 5239
5240 -- The dereference is added either in Analyze_Call or here. Should
5241 -- be consolidated ???
5242
5243 Set_Is_Overloaded (Subp, False);
5244 Set_Etype (Subp, Etype (Nam));
5245 Insert_Explicit_Dereference (Subp);
5246 Nam := Designated_Type (Etype (Nam));
5247 Resolve (Subp, Nam);
5248 end if;
5249
996ae0b0
RK		 5250 -- Check that a call to Current_Task does not occur in an entry body
5251
5252 if Is_RTE (Nam, RE_Current_Task) then
5253 declare
5254 P : Node_Id;
5255
5256 begin
5257 P := N;
5258 loop
5259 P := Parent (P);
45fc7ddb
HK		 5260
5261 -- Exclude calls that occur within the default of a formal
5262 -- parameter of the entry, since those are evaluated outside
5263 -- of the body.
5264
5265 exit when No (P) or else Nkind (P) = N_Parameter_Specification;
996ae0b0 5266
aa180613
RD		 5267 if Nkind (P) = N_Entry_Body
5268 or else (Nkind (P) = N_Subprogram_Body
45fc7ddb 5269 and then Is_Entry_Barrier_Function (P))
aa180613
RD		 5270 then
5271 Rtype := Etype (N);
996ae0b0 5272 Error_Msg_NE
aa5147f0 5273 ("?& should not be used in entry body (RM C.7(17))",
996ae0b0 5274 N, Nam);
aa180613
RD		 5275 Error_Msg_NE
5276 ("\Program_Error will be raised at run time?", N, Nam);
5277 Rewrite (N,
5278 Make_Raise_Program_Error (Loc,
5279 Reason => PE_Current_Task_In_Entry_Body));
5280 Set_Etype (N, Rtype);
e65f50ec 5281 return;
996ae0b0
RK		 5282 end if;
5283 end loop;
5284 end;
5285 end if;
5286
758c442c
GD		 5287 -- Check that a procedure call does not occur in the context of the
5288 -- entry call statement of a conditional or timed entry call. Note that
5289 -- the case of a call to a subprogram renaming of an entry will also be
5290 -- rejected. The test for N not being an N_Entry_Call_Statement is
5291 -- defensive, covering the possibility that the processing of entry
5292 -- calls might reach this point due to later modifications of the code
5293 -- above.
996ae0b0
RK		 5294
5295 if Nkind (Parent (N)) = N_Entry_Call_Alternative
5296 and then Nkind (N) /= N_Entry_Call_Statement
5297 and then Entry_Call_Statement (Parent (N)) = N
5298 then
0791fbe9 5299 if Ada_Version < Ada_2005 then
1420b484
JM		 5300 Error_Msg_N ("entry call required in select statement", N);
5301
5302 -- Ada 2005 (AI-345): If a procedure_call_statement is used
66aa7643
TQ		 5303 -- for a procedure_or_entry_call, the procedure_name or
5304 -- procedure_prefix of the procedure_call_statement shall denote
1420b484
JM		 5305 -- an entry renamed by a procedure, or (a view of) a primitive
5306 -- subprogram of a limited interface whose first parameter is
5307 -- a controlling parameter.
5308
5309 elsif Nkind (N) = N_Procedure_Call_Statement
5310 and then not Is_Renamed_Entry (Nam)
5311 and then not Is_Controlling_Limited_Procedure (Nam)
5312 then
5313 Error_Msg_N
c8ef728f 5314 ("entry call or dispatching primitive of interface required", N);
1420b484 5315 end if;
996ae0b0
RK		 5316 end if;
5317
66aa7643
TQ		 5318 -- Check that this is not a call to a protected procedure or entry from
5319 -- within a protected function.
fbf5a39b
AC		 5320
5321 if Ekind (Current_Scope) = E_Function
5322 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
5323 and then Ekind (Nam) /= E_Function
5324 and then Scope (Nam) = Scope (Current_Scope)
5325 then
5326 Error_Msg_N ("within protected function, protected " &
5327 "object is constant", N);
5328 Error_Msg_N ("\cannot call operation that may modify it", N);
5329 end if;
5330
45fc7ddb 5331 -- Freeze the subprogram name if not in a spec-expression. Note that we
758c442c
GD		 5332 -- freeze procedure calls as well as function calls. Procedure calls are
5333 -- not frozen according to the rules (RM 13.14(14)) because it is
5334 -- impossible to have a procedure call to a non-frozen procedure in pure
5335 -- Ada, but in the code that we generate in the expander, this rule
5336 -- needs extending because we can generate procedure calls that need
5337 -- freezing.
996ae0b0 5338
a429e6b3
AC		 5339 -- In Ada 2012, expression functions may be called within pre/post
5340 -- conditions of subsequent functions or expression functions. Such
5341 -- calls do not freeze when they appear within generated bodies, which
5342 -- would place the freeze node in the wrong scope. An expression
5343 -- function is frozen in the usual fashion, by the appearance of a real
5344 -- body, or at the end of a declarative part.
5345
5346 if Is_Entity_Name (Subp) and then not In_Spec_Expression
5347 and then
5348 (not Is_Expression_Function (Entity (Subp))
5349 or else Scope (Entity (Subp)) = Current_Scope)
5350 then
996ae0b0
RK		 5351 Freeze_Expression (Subp);
5352 end if;
5353
758c442c
GD		 5354 -- For a predefined operator, the type of the result is the type imposed
5355 -- by context, except for a predefined operation on universal fixed.
5356 -- Otherwise The type of the call is the type returned by the subprogram
5357 -- being called.
996ae0b0
RK		 5358
5359 if Is_Predefined_Op (Nam) then
996ae0b0
RK		 5360 if Etype (N) /= Universal_Fixed then
5361 Set_Etype (N, Typ);
5362 end if;
5363
758c442c
GD		 5364 -- If the subprogram returns an array type, and the context requires the
5365 -- component type of that array type, the node is really an indexing of
5366 -- the parameterless call. Resolve as such. A pathological case occurs
5367 -- when the type of the component is an access to the array type. In
5368 -- this case the call is truly ambiguous.
996ae0b0 5369
0669bebe 5370 elsif (Needs_No_Actuals (Nam) or else Needs_One_Actual (Nam))
996ae0b0
RK		 5371 and then
5372 ((Is_Array_Type (Etype (Nam))
19fb051c 5373 and then Covers (Typ, Component_Type (Etype (Nam))))
996ae0b0 5374 or else (Is_Access_Type (Etype (Nam))
19fb051c
AC		 5375 and then Is_Array_Type (Designated_Type (Etype (Nam)))
5376 and then
5377 Covers
5378 (Typ,
5379 Component_Type (Designated_Type (Etype (Nam))))))
996ae0b0
RK		 5380 then
5381 declare
5382 Index_Node : Node_Id;
fbf5a39b
AC		 5383 New_Subp : Node_Id;
5384 Ret_Type : constant Entity_Id := Etype (Nam);
996ae0b0
RK		 5385
5386 begin
fbf5a39b
AC		 5387 if Is_Access_Type (Ret_Type)
5388 and then Ret_Type = Component_Type (Designated_Type (Ret_Type))
5389 then
5390 Error_Msg_N
5391 ("cannot disambiguate function call and indexing", N);
5392 else
5393 New_Subp := Relocate_Node (Subp);
5394 Set_Entity (Subp, Nam);
5395
7205254b 5396 if (Is_Array_Type (Ret_Type)
5d5e9775 5397 and then Component_Type (Ret_Type) /= Any_Type)
7205254b
JM		 5398 or else
5399 (Is_Access_Type (Ret_Type)
5d5e9775
AC		 5400 and then
5401 Component_Type (Designated_Type (Ret_Type)) /= Any_Type)
7205254b 5402 then
0669bebe
GB		 5403 if Needs_No_Actuals (Nam) then
5404
5405 -- Indexed call to a parameterless function
5406
5407 Index_Node :=
5408 Make_Indexed_Component (Loc,
5409 Prefix =>
5410 Make_Function_Call (Loc,
5411 Name => New_Subp),
5412 Expressions => Parameter_Associations (N));
5413 else
5414 -- An Ada 2005 prefixed call to a primitive operation
5415 -- whose first parameter is the prefix. This prefix was
5416 -- prepended to the parameter list, which is actually a
3b42c566 5417 -- list of indexes. Remove the prefix in order to build
0669bebe
GB		 5418 -- the proper indexed component.
5419
5420 Index_Node :=
5421 Make_Indexed_Component (Loc,
5422 Prefix =>
5423 Make_Function_Call (Loc,
5424 Name => New_Subp,
5425 Parameter_Associations =>
5426 New_List
5427 (Remove_Head (Parameter_Associations (N)))),
5428 Expressions => Parameter_Associations (N));
5429 end if;
fbf5a39b 5430
74e7891f
RD		 5431 -- Preserve the parenthesis count of the node
5432
5433 Set_Paren_Count (Index_Node, Paren_Count (N));
5434
fbf5a39b
AC		 5435 -- Since we are correcting a node classification error made
5436 -- by the parser, we call Replace rather than Rewrite.
5437
5438 Replace (N, Index_Node);
74e7891f 5439
fbf5a39b
AC		 5440 Set_Etype (Prefix (N), Ret_Type);
5441 Set_Etype (N, Typ);
5442 Resolve_Indexed_Component (N, Typ);
5443 Check_Elab_Call (Prefix (N));
5444 end if;
996ae0b0
RK		 5445 end if;
5446
5447 return;
5448 end;
5449
5450 else
5451 Set_Etype (N, Etype (Nam));
5452 end if;
5453
5454 -- In the case where the call is to an overloaded subprogram, Analyze
5455 -- calls Normalize_Actuals once per overloaded subprogram. Therefore in
5456 -- such a case Normalize_Actuals needs to be called once more to order
5457 -- the actuals correctly. Otherwise the call will have the ordering
5458 -- given by the last overloaded subprogram whether this is the correct
5459 -- one being called or not.
5460
5461 if Is_Overloaded (Subp) then
5462 Normalize_Actuals (N, Nam, False, Norm_OK);
5463 pragma Assert (Norm_OK);
5464 end if;
5465
5466 -- In any case, call is fully resolved now. Reset Overload flag, to
5467 -- prevent subsequent overload resolution if node is analyzed again
5468
5469 Set_Is_Overloaded (Subp, False);
5470 Set_Is_Overloaded (N, False);
5471
758c442c
GD		 5472 -- If we are calling the current subprogram from immediately within its
5473 -- body, then that is the case where we can sometimes detect cases of
5474 -- infinite recursion statically. Do not try this in case restriction
b7d1f17f 5475 -- No_Recursion is in effect anyway, and do it only for source calls.
996ae0b0 5476
b7d1f17f
HK		 5477 if Comes_From_Source (N) then
5478 Scop := Current_Scope;
996ae0b0 5479
26570b21
RD		 5480 -- Issue warning for possible infinite recursion in the absence
5481 -- of the No_Recursion restriction.
5482
ee81cbe9 5483 if Same_Or_Aliased_Subprograms (Nam, Scop)
b7d1f17f
HK		 5484 and then not Restriction_Active (No_Recursion)
5485 and then Check_Infinite_Recursion (N)
5486 then
5487 -- Here we detected and flagged an infinite recursion, so we do
da20aa43
RD		 5488 -- not need to test the case below for further warnings. Also we
5489 -- are all done if we now have a raise SE node.
996ae0b0 5490
26570b21
RD		 5491 if Nkind (N) = N_Raise_Storage_Error then
5492 return;
5493 end if;
996ae0b0 5494
26570b21
RD		 5495 -- If call is to immediately containing subprogram, then check for
5496 -- the case of a possible run-time detectable infinite recursion.
996ae0b0 5497
b7d1f17f
HK		 5498 else
5499 Scope_Loop : while Scop /= Standard_Standard loop
ee81cbe9 5500 if Same_Or_Aliased_Subprograms (Nam, Scop) then
b7d1f17f
HK		 5501
5502 -- Although in general case, recursion is not statically
5503 -- checkable, the case of calling an immediately containing
5504 -- subprogram is easy to catch.
5505
5506 Check_Restriction (No_Recursion, N);
5507
5508 -- If the recursive call is to a parameterless subprogram,
5509 -- then even if we can't statically detect infinite
5510 -- recursion, this is pretty suspicious, and we output a
5511 -- warning. Furthermore, we will try later to detect some
5512 -- cases here at run time by expanding checking code (see
5513 -- Detect_Infinite_Recursion in package Exp_Ch6).
5514
5515 -- If the recursive call is within a handler, do not emit a
5516 -- warning, because this is a common idiom: loop until input
5517 -- is correct, catch illegal input in handler and restart.
5518
5519 if No (First_Formal (Nam))
5520 and then Etype (Nam) = Standard_Void_Type
5521 and then not Error_Posted (N)
5522 and then Nkind (Parent (N)) /= N_Exception_Handler
aa180613 5523 then
b7d1f17f
HK		 5524 -- For the case of a procedure call. We give the message
5525 -- only if the call is the first statement in a sequence
5526 -- of statements, or if all previous statements are
5527 -- simple assignments. This is simply a heuristic to
5528 -- decrease false positives, without losing too many good
5529 -- warnings. The idea is that these previous statements
5530 -- may affect global variables the procedure depends on.
78efd712
AC		 5531 -- We also exclude raise statements, that may arise from
5532 -- constraint checks and are probably unrelated to the
5533 -- intended control flow.
b7d1f17f
HK		 5534
5535 if Nkind (N) = N_Procedure_Call_Statement
5536 and then Is_List_Member (N)
5537 then
5538 declare
5539 P : Node_Id;
5540 begin
5541 P := Prev (N);
5542 while Present (P) loop
78efd712
AC		 5543 if not Nkind_In (P,
5544 N_Assignment_Statement,
5545 N_Raise_Constraint_Error)
5546 then
b7d1f17f
HK		 5547 exit Scope_Loop;
5548 end if;
5549
5550 Prev (P);
5551 end loop;
5552 end;
5553 end if;
5554
5555 -- Do not give warning if we are in a conditional context
5556
aa180613 5557 declare
b7d1f17f 5558 K : constant Node_Kind := Nkind (Parent (N));
aa180613 5559 begin
b7d1f17f 5560 if (K = N_Loop_Statement
b5c739f9 5561 and then Present (Iteration_Scheme (Parent (N))))
b7d1f17f
HK		 5562 or else K = N_If_Statement
5563 or else K = N_Elsif_Part
5564 or else K = N_Case_Statement_Alternative
5565 then
5566 exit Scope_Loop;
5567 end if;
aa180613 5568 end;
aa180613 5569
b7d1f17f 5570 -- Here warning is to be issued
aa180613 5571
b7d1f17f
HK		 5572 Set_Has_Recursive_Call (Nam);
5573 Error_Msg_N
aa5147f0 5574 ("?possible infinite recursion!", N);
b7d1f17f 5575 Error_Msg_N
aa5147f0 5576 ("\?Storage_Error may be raised at run time!", N);
b7d1f17f 5577 end if;
aa180613 5578
b7d1f17f 5579 exit Scope_Loop;
996ae0b0
RK		 5580 end if;
5581
b7d1f17f
HK		 5582 Scop := Scope (Scop);
5583 end loop Scope_Loop;
5584 end if;
996ae0b0
RK		 5585 end if;
5586
b5c739f9
RD		 5587 -- Check obsolescent reference to Ada.Characters.Handling subprogram
5588
5589 Check_Obsolescent_2005_Entity (Nam, Subp);
5590
996ae0b0
RK		 5591 -- If subprogram name is a predefined operator, it was given in
5592 -- functional notation. Replace call node with operator node, so
5593 -- that actuals can be resolved appropriately.
5594
5595 if Is_Predefined_Op (Nam) or else Ekind (Nam) = E_Operator then
5596 Make_Call_Into_Operator (N, Typ, Entity (Name (N)));
5597 return;
5598
5599 elsif Present (Alias (Nam))
5600 and then Is_Predefined_Op (Alias (Nam))
5601 then
5602 Resolve_Actuals (N, Nam);
5603 Make_Call_Into_Operator (N, Typ, Alias (Nam));
5604 return;
5605 end if;
5606
fbf5a39b
AC		 5607 -- Create a transient scope if the resulting type requires it
5608
4017021b
AC		 5609 -- There are several notable exceptions:
5610
4d2907fd 5611 -- a) In init procs, the transient scope overhead is not needed, and is
4017021b
AC		 5612 -- even incorrect when the call is a nested initialization call for a
5613 -- component whose expansion may generate adjust calls. However, if the
5614 -- call is some other procedure call within an initialization procedure
5615 -- (for example a call to Create_Task in the init_proc of the task
5616 -- run-time record) a transient scope must be created around this call.
5617
4d2907fd 5618 -- b) Enumeration literal pseudo-calls need no transient scope
4017021b 5619
4d2907fd 5620 -- c) Intrinsic subprograms (Unchecked_Conversion and source info
4017021b 5621 -- functions) do not use the secondary stack even though the return
4d2907fd 5622 -- type may be unconstrained.
4017021b 5623
4d2907fd 5624 -- d) Calls to a build-in-place function, since such functions may
4017021b
AC		 5625 -- allocate their result directly in a target object, and cases where
5626 -- the result does get allocated in the secondary stack are checked for
5627 -- within the specialized Exp_Ch6 procedures for expanding those
5628 -- build-in-place calls.
5629
5630 -- e) If the subprogram is marked Inline_Always, then even if it returns
c8ef728f 5631 -- an unconstrained type the call does not require use of the secondary
45fc7ddb
HK		 5632 -- stack. However, inlining will only take place if the body to inline
5633 -- is already present. It may not be available if e.g. the subprogram is
5634 -- declared in a child instance.
c8ef728f 5635
4017021b
AC		 5636 -- If this is an initialization call for a type whose construction
5637 -- uses the secondary stack, and it is not a nested call to initialize
5638 -- a component, we do need to create a transient scope for it. We
5639 -- check for this by traversing the type in Check_Initialization_Call.
5640
c8ef728f 5641 if Is_Inlined (Nam)
45fc7ddb
HK		 5642 and then Has_Pragma_Inline_Always (Nam)
5643 and then Nkind (Unit_Declaration_Node (Nam)) = N_Subprogram_Declaration
5644 and then Present (Body_To_Inline (Unit_Declaration_Node (Nam)))
84f4072a
JM		 5645 and then not Debug_Flag_Dot_K
5646 then
5647 null;
5648
5649 elsif Is_Inlined (Nam)
5650 and then Has_Pragma_Inline (Nam)
5651 and then Nkind (Unit_Declaration_Node (Nam)) = N_Subprogram_Declaration
5652 and then Present (Body_To_Inline (Unit_Declaration_Node (Nam)))
5653 and then Debug_Flag_Dot_K
c8ef728f
ES		 5654 then
5655 null;
5656
4017021b
AC		 5657 elsif Ekind (Nam) = E_Enumeration_Literal
5658 or else Is_Build_In_Place_Function (Nam)
5659 or else Is_Intrinsic_Subprogram (Nam)
5660 then
5661 null;
5662
da94696d 5663 elsif Full_Expander_Active
996ae0b0
RK		 5664 and then Is_Type (Etype (Nam))
5665 and then Requires_Transient_Scope (Etype (Nam))
4017021b
AC		 5666 and then
5667 (not Within_Init_Proc
5668 or else
5669 (not Is_Init_Proc (Nam) and then Ekind (Nam) /= E_Function))
996ae0b0 5670 then
0669bebe 5671 Establish_Transient_Scope (N, Sec_Stack => True);
996ae0b0 5672
a9f4e3d2
AC		 5673 -- If the call appears within the bounds of a loop, it will
5674 -- be rewritten and reanalyzed, nothing left to do here.
5675
5676 if Nkind (N) /= N_Function_Call then
5677 return;
5678 end if;
5679
fbf5a39b 5680 elsif Is_Init_Proc (Nam)
996ae0b0
RK		 5681 and then not Within_Init_Proc
5682 then
5683 Check_Initialization_Call (N, Nam);
5684 end if;
5685
5686 -- A protected function cannot be called within the definition of the
5687 -- enclosing protected type.
5688
5689 if Is_Protected_Type (Scope (Nam))
5690 and then In_Open_Scopes (Scope (Nam))
5691 and then not Has_Completion (Scope (Nam))
5692 then
5693 Error_Msg_NE
5694 ("& cannot be called before end of protected definition", N, Nam);
5695 end if;
5696
5697 -- Propagate interpretation to actuals, and add default expressions
5698 -- where needed.
5699
5700 if Present (First_Formal (Nam)) then
5701 Resolve_Actuals (N, Nam);
5702
d81b4bfe
TQ		 5703 -- Overloaded literals are rewritten as function calls, for purpose of
5704 -- resolution. After resolution, we can replace the call with the
5705 -- literal itself.
996ae0b0
RK		 5706
5707 elsif Ekind (Nam) = E_Enumeration_Literal then
5708 Copy_Node (Subp, N);
5709 Resolve_Entity_Name (N, Typ);
5710
fbf5a39b 5711 -- Avoid validation, since it is a static function call
996ae0b0 5712
e65f50ec 5713 Generate_Reference (Nam, Subp);
996ae0b0
RK		 5714 return;
5715 end if;
5716
b7d1f17f
HK		 5717 -- If the subprogram is not global, then kill all saved values and
5718 -- checks. This is a bit conservative, since in many cases we could do
5719 -- better, but it is not worth the effort. Similarly, we kill constant
5720 -- values. However we do not need to do this for internal entities
5721 -- (unless they are inherited user-defined subprograms), since they
5722 -- are not in the business of molesting local values.
5723
5724 -- If the flag Suppress_Value_Tracking_On_Calls is set, then we also
5725 -- kill all checks and values for calls to global subprograms. This
5726 -- takes care of the case where an access to a local subprogram is
5727 -- taken, and could be passed directly or indirectly and then called
5728 -- from almost any context.
aa180613
RD		 5729
5730 -- Note: we do not do this step till after resolving the actuals. That
5731 -- way we still take advantage of the current value information while
5732 -- scanning the actuals.
5733
45fc7ddb
HK		 5734 -- We suppress killing values if we are processing the nodes associated
5735 -- with N_Freeze_Entity nodes. Otherwise the declaration of a tagged
5736 -- type kills all the values as part of analyzing the code that
5737 -- initializes the dispatch tables.
5738
5739 if Inside_Freezing_Actions = 0
5740 and then (not Is_Library_Level_Entity (Nam)
24357840
RD		 5741 or else Suppress_Value_Tracking_On_Call
5742 (Nearest_Dynamic_Scope (Current_Scope)))
aa180613
RD		 5743 and then (Comes_From_Source (Nam)
5744 or else (Present (Alias (Nam))
5745 and then Comes_From_Source (Alias (Nam))))
5746 then
5747 Kill_Current_Values;
5748 end if;
5749
36fcf362
RD		 5750 -- If we are warning about unread OUT parameters, this is the place to
5751 -- set Last_Assignment for OUT and IN OUT parameters. We have to do this
5752 -- after the above call to Kill_Current_Values (since that call clears
5753 -- the Last_Assignment field of all local variables).
67ce0d7e 5754
36fcf362 5755 if (Warn_On_Modified_Unread or Warn_On_All_Unread_Out_Parameters)
67ce0d7e
RD		 5756 and then Comes_From_Source (N)
5757 and then In_Extended_Main_Source_Unit (N)
5758 then
5759 declare
5760 F : Entity_Id;
5761 A : Node_Id;
5762
5763 begin
5764 F := First_Formal (Nam);
5765 A := First_Actual (N);
5766 while Present (F) and then Present (A) loop
964f13da 5767 if Ekind_In (F, E_Out_Parameter, E_In_Out_Parameter)
36fcf362 5768 and then Warn_On_Modified_As_Out_Parameter (F)
67ce0d7e
RD		 5769 and then Is_Entity_Name (A)
5770 and then Present (Entity (A))
36fcf362 5771 and then Comes_From_Source (N)
67ce0d7e
RD		 5772 and then Safe_To_Capture_Value (N, Entity (A))
5773 then
5774 Set_Last_Assignment (Entity (A), A);
5775 end if;
5776
5777 Next_Formal (F);
5778 Next_Actual (A);
5779 end loop;
5780 end;
5781 end if;
5782
996ae0b0
RK		 5783 -- If the subprogram is a primitive operation, check whether or not
5784 -- it is a correct dispatching call.
5785
5786 if Is_Overloadable (Nam)
5787 and then Is_Dispatching_Operation (Nam)
5788 then
5789 Check_Dispatching_Call (N);
5790
0669bebe
GB		 5791 elsif Ekind (Nam) /= E_Subprogram_Type
5792 and then Is_Abstract_Subprogram (Nam)
996ae0b0
RK		 5793 and then not In_Instance
5794 then
5795 Error_Msg_NE ("cannot call abstract subprogram &!", N, Nam);
5796 end if;
5797
e65f50ec
ES		 5798 -- If this is a dispatching call, generate the appropriate reference,
5799 -- for better source navigation in GPS.
5800
5801 if Is_Overloadable (Nam)
5802 and then Present (Controlling_Argument (N))
5803 then
5804 Generate_Reference (Nam, Subp, 'R');
c5d91669 5805
5cc9353d 5806 -- Normal case, not a dispatching call: generate a call reference
c5d91669 5807
e65f50ec 5808 else
9c870c90 5809 Generate_Reference (Nam, Subp, 's');
e65f50ec
ES		 5810 end if;
5811
996ae0b0
RK		 5812 if Is_Intrinsic_Subprogram (Nam) then
5813 Check_Intrinsic_Call (N);
5814 end if;
5815
5b2217f8 5816 -- Check for violation of restriction No_Specific_Termination_Handlers
dce86910 5817 -- and warn on a potentially blocking call to Abort_Task.
5b2217f8 5818
273adcdf
AC		 5819 if Restriction_Check_Required (No_Specific_Termination_Handlers)
5820 and then (Is_RTE (Nam, RE_Set_Specific_Handler)
5821 or else
5822 Is_RTE (Nam, RE_Specific_Handler))
5b2217f8
RD		 5823 then
5824 Check_Restriction (No_Specific_Termination_Handlers, N);
dce86910
AC		 5825
5826 elsif Is_RTE (Nam, RE_Abort_Task) then
5827 Check_Potentially_Blocking_Operation (N);
5b2217f8
RD		 5828 end if;
5829
806f6d37
AC		 5830 -- A call to Ada.Real_Time.Timing_Events.Set_Handler to set a relative
5831 -- timing event violates restriction No_Relative_Delay (AI-0211). We
5832 -- need to check the second argument to determine whether it is an
5833 -- absolute or relative timing event.
afbcdf5e 5834
273adcdf
AC		 5835 if Restriction_Check_Required (No_Relative_Delay)
5836 and then Is_RTE (Nam, RE_Set_Handler)
806f6d37
AC		 5837 and then Is_RTE (Etype (Next_Actual (First_Actual (N))), RE_Time_Span)
5838 then
afbcdf5e
AC		 5839 Check_Restriction (No_Relative_Delay, N);
5840 end if;
5841
21791d97
AC		 5842 -- Issue an error for a call to an eliminated subprogram. This routine
5843 -- will not perform the check if the call appears within a default
5844 -- expression.
16212e89 5845
df378148 5846 Check_For_Eliminated_Subprogram (Subp, Nam);
16212e89 5847
12f0c50c
AC		 5848 -- In formal mode, the primitive operations of a tagged type or type
5849 -- extension do not include functions that return the tagged type.
5850
5851 -- Commented out as the call to Is_Inherited_Operation_For_Type may
5852 -- cause an error because the type entity of the parent node of
ded8909b
AC		 5853 -- Entity (Name (N) may not be set. ???
5854 -- So why not just add a guard ???
12f0c50c
AC		 5855
5856-- if Nkind (N) = N_Function_Call
5857-- and then Is_Tagged_Type (Etype (N))
5858-- and then Is_Entity_Name (Name (N))
5859-- and then Is_Inherited_Operation_For_Type
ded8909b 5860-- (Entity (Name (N)), Etype (N))
12f0c50c 5861-- then
c4d67e2d 5862-- Check_SPARK_Restriction ("function not inherited", N);
12f0c50c
AC		 5863-- end if;
5864
e8374e7a
AC		 5865 -- Implement rule in 12.5.1 (23.3/2): In an instance, if the actual is
5866 -- class-wide and the call dispatches on result in a context that does
5867 -- not provide a tag, the call raises Program_Error.
1f6439e3
AC		 5868
5869 if Nkind (N) = N_Function_Call
5870 and then In_Instance
5871 and then Is_Generic_Actual_Type (Typ)
5872 and then Is_Class_Wide_Type (Typ)
5873 and then Has_Controlling_Result (Nam)
5874 and then Nkind (Parent (N)) = N_Object_Declaration
5875 then
e8374e7a 5876 -- Verify that none of the formals are controlling
1f6439e3
AC		 5877
5878 declare
e8374e7a 5879 Call_OK : Boolean := False;
1f6439e3
AC		 5880 F : Entity_Id;
5881
5882 begin
5883 F := First_Formal (Nam);
5884 while Present (F) loop
5885 if Is_Controlling_Formal (F) then
5886 Call_OK := True;
5887 exit;
5888 end if;
e8374e7a 5889
1f6439e3
AC		 5890 Next_Formal (F);
5891 end loop;
5892
5893 if not Call_OK then
5894 Error_Msg_N ("!? cannot determine tag of result", N);
5895 Error_Msg_N ("!? Program_Error will be raised", N);
5896 Insert_Action (N,
5897 Make_Raise_Program_Error (Sloc (N),
5898 Reason => PE_Explicit_Raise));
5899 end if;
5900 end;
5901 end if;
5902
dec6faf1
AC		 5903 Analyze_Dimension (N);
5904
67ce0d7e
RD		 5905 -- All done, evaluate call and deal with elaboration issues
5906
c01a9391 5907 Eval_Call (N);
996ae0b0 5908 Check_Elab_Call (N);
76b84bf0 5909 Warn_On_Overlapping_Actuals (Nam, N);
996ae0b0
RK		 5910 end Resolve_Call;
5911
19d846a0
RD		 5912 -----------------------------
5913 -- Resolve_Case_Expression --
5914 -----------------------------
5915
5916 procedure Resolve_Case_Expression (N : Node_Id; Typ : Entity_Id) is
5917 Alt : Node_Id;
5918
5919 begin
5920 Alt := First (Alternatives (N));
5921 while Present (Alt) loop
5922 Resolve (Expression (Alt), Typ);
5923 Next (Alt);
5924 end loop;
5925
5926 Set_Etype (N, Typ);
5927 Eval_Case_Expression (N);
5928 end Resolve_Case_Expression;
5929
996ae0b0
RK		 5930 -------------------------------
5931 -- Resolve_Character_Literal --
5932 -------------------------------
5933
5934 procedure Resolve_Character_Literal (N : Node_Id; Typ : Entity_Id) is
5935 B_Typ : constant Entity_Id := Base_Type (Typ);
5936 C : Entity_Id;
5937
5938 begin
5939 -- Verify that the character does belong to the type of the context
5940
5941 Set_Etype (N, B_Typ);
5942 Eval_Character_Literal (N);
5943
82c80734
RD		 5944 -- Wide_Wide_Character literals must always be defined, since the set
5945 -- of wide wide character literals is complete, i.e. if a character
5946 -- literal is accepted by the parser, then it is OK for wide wide
5947 -- character (out of range character literals are rejected).
996ae0b0 5948
82c80734 5949 if Root_Type (B_Typ) = Standard_Wide_Wide_Character then
996ae0b0
RK		 5950 return;
5951
5952 -- Always accept character literal for type Any_Character, which
5953 -- occurs in error situations and in comparisons of literals, both
5954 -- of which should accept all literals.
5955
5956 elsif B_Typ = Any_Character then
5957 return;
5958
5cc9353d
RD		 5959 -- For Standard.Character or a type derived from it, check that the
5960 -- literal is in range.
996ae0b0
RK		 5961
5962 elsif Root_Type (B_Typ) = Standard_Character then
82c80734
RD		 5963 if In_Character_Range (UI_To_CC (Char_Literal_Value (N))) then
5964 return;
5965 end if;
5966
5cc9353d
RD		 5967 -- For Standard.Wide_Character or a type derived from it, check that the
5968 -- literal is in range.
82c80734
RD		 5969
5970 elsif Root_Type (B_Typ) = Standard_Wide_Character then
5971 if In_Wide_Character_Range (UI_To_CC (Char_Literal_Value (N))) then
996ae0b0
RK		 5972 return;
5973 end if;
5974
82c80734
RD		 5975 -- For Standard.Wide_Wide_Character or a type derived from it, we
5976 -- know the literal is in range, since the parser checked!
5977
5978 elsif Root_Type (B_Typ) = Standard_Wide_Wide_Character then
5979 return;
5980
d81b4bfe
TQ		 5981 -- If the entity is already set, this has already been resolved in a
5982 -- generic context, or comes from expansion. Nothing else to do.
996ae0b0
RK		 5983
5984 elsif Present (Entity (N)) then
5985 return;
5986
d81b4bfe
TQ		 5987 -- Otherwise we have a user defined character type, and we can use the
5988 -- standard visibility mechanisms to locate the referenced entity.
996ae0b0
RK		 5989
5990 else
5991 C := Current_Entity (N);
996ae0b0
RK		 5992 while Present (C) loop
5993 if Etype (C) = B_Typ then
5994 Set_Entity_With_Style_Check (N, C);
5995 Generate_Reference (C, N);
5996 return;
5997 end if;
5998
5999 C := Homonym (C);
6000 end loop;
6001 end if;
6002
6003 -- If we fall through, then the literal does not match any of the
5cc9353d
RD		 6004 -- entries of the enumeration type. This isn't just a constraint error
6005 -- situation, it is an illegality (see RM 4.2).
996ae0b0
RK		 6006
6007 Error_Msg_NE
6008 ("character not defined for }", N, First_Subtype (B_Typ));
996ae0b0
RK		 6009 end Resolve_Character_Literal;
6010
6011 ---------------------------
6012 -- Resolve_Comparison_Op --
6013 ---------------------------
6014
6015 -- Context requires a boolean type, and plays no role in resolution.
5cc9353d
RD		 6016 -- Processing identical to that for equality operators. The result type is
6017 -- the base type, which matters when pathological subtypes of booleans with
6018 -- limited ranges are used.
996ae0b0
RK		 6019
6020 procedure Resolve_Comparison_Op (N : Node_Id; Typ : Entity_Id) is
6021 L : constant Node_Id := Left_Opnd (N);
6022 R : constant Node_Id := Right_Opnd (N);
6023 T : Entity_Id;
6024
6025 begin
d81b4bfe
TQ		 6026 -- If this is an intrinsic operation which is not predefined, use the
6027 -- types of its declared arguments to resolve the possibly overloaded
6028 -- operands. Otherwise the operands are unambiguous and specify the
6029 -- expected type.
996ae0b0
RK		 6030
6031 if Scope (Entity (N)) /= Standard_Standard then
6032 T := Etype (First_Entity (Entity (N)));
1420b484 6033
996ae0b0
RK		 6034 else
6035 T := Find_Unique_Type (L, R);
6036
6037 if T = Any_Fixed then
6038 T := Unique_Fixed_Point_Type (L);
6039 end if;
6040 end if;
6041
fbf5a39b 6042 Set_Etype (N, Base_Type (Typ));
996ae0b0
RK		 6043 Generate_Reference (T, N, ' ');
6044
bd29d519 6045 -- Skip remaining processing if already set to Any_Type
996ae0b0 6046
bd29d519
AC		 6047 if T = Any_Type then
6048 return;
6049 end if;
6050
6051 -- Deal with other error cases
996ae0b0 6052
bd29d519
AC		 6053 if T = Any_String or else
6054 T = Any_Composite or else
6055 T = Any_Character
6056 then
6057 if T = Any_Character then
6058 Ambiguous_Character (L);
996ae0b0 6059 else
bd29d519 6060 Error_Msg_N ("ambiguous operands for comparison", N);
996ae0b0 6061 end if;
bd29d519
AC		 6062
6063 Set_Etype (N, Any_Type);
6064 return;
996ae0b0 6065 end if;
bd29d519
AC		 6066
6067 -- Resolve the operands if types OK
6068
6069 Resolve (L, T);
6070 Resolve (R, T);
6071 Check_Unset_Reference (L);
6072 Check_Unset_Reference (R);
6073 Generate_Operator_Reference (N, T);
6074 Check_Low_Bound_Tested (N);
6075
2ba431e5
YM		 6076 -- In SPARK, ordering operators <, <=, >, >= are not defined for Boolean
6077 -- types or array types except String.
b0186f71 6078
fe5d3068 6079 if Is_Boolean_Type (T) then
2ba431e5 6080 Check_SPARK_Restriction
fe5d3068 6081 ("comparison is not defined on Boolean type", N);
975c6896 6082
ad05f2e9
AC		 6083 elsif Is_Array_Type (T)
6084 and then Base_Type (T) /= Standard_String
6085 then
6086 Check_SPARK_Restriction
6087 ("comparison is not defined on array types other than String", N);
b0186f71
AC		 6088 end if;
6089
bd29d519
AC		 6090 -- Check comparison on unordered enumeration
6091
6092 if Comes_From_Source (N)
6093 and then Bad_Unordered_Enumeration_Reference (N, Etype (L))
6094 then
6095 Error_Msg_N ("comparison on unordered enumeration type?", N);
6096 end if;
6097
5cc9353d
RD		 6098 -- Evaluate the relation (note we do this after the above check since
6099 -- this Eval call may change N to True/False.
bd29d519 6100
dec6faf1 6101 Analyze_Dimension (N);
bd29d519 6102 Eval_Relational_Op (N);
996ae0b0
RK		 6103 end Resolve_Comparison_Op;
6104
6105 ------------------------------------
6106 -- Resolve_Conditional_Expression --
6107 ------------------------------------
6108
6109 procedure Resolve_Conditional_Expression (N : Node_Id; Typ : Entity_Id) is
6110 Condition : constant Node_Id := First (Expressions (N));
6111 Then_Expr : constant Node_Id := Next (Condition);
19fb051c 6112 Else_Expr : Node_Id := Next (Then_Expr);
36504e5f
AC		 6113 Else_Typ : Entity_Id;
6114 Then_Typ : Entity_Id;
b46be8a2 6115
996ae0b0 6116 begin
b46be8a2 6117 Resolve (Condition, Any_Boolean);
996ae0b0 6118 Resolve (Then_Expr, Typ);
36504e5f
AC		 6119 Then_Typ := Etype (Then_Expr);
6120
6121 -- When the "then" and "else" expressions are of a scalar type, insert
6122 -- a conversion to ensure the generation of a constraint check.
6123
6124 if Is_Scalar_Type (Then_Typ)
6125 and then Then_Typ /= Typ
6126 then
6127 Rewrite (Then_Expr, Convert_To (Typ, Then_Expr));
6128 Analyze_And_Resolve (Then_Expr, Typ);
6129 end if;
b46be8a2
RD		 6130
6131 -- If ELSE expression present, just resolve using the determined type
6132
6133 if Present (Else_Expr) then
6134 Resolve (Else_Expr, Typ);
36504e5f
AC		 6135 Else_Typ := Etype (Else_Expr);
6136
6137 if Is_Scalar_Type (Else_Typ)
6138 and then Else_Typ /= Typ
6139 then
6140 Rewrite (Else_Expr, Convert_To (Typ, Else_Expr));
6141 Analyze_And_Resolve (Else_Expr, Typ);
6142 end if;
b46be8a2
RD		 6143
6144 -- If no ELSE expression is present, root type must be Standard.Boolean
6145 -- and we provide a Standard.True result converted to the appropriate
6146 -- Boolean type (in case it is a derived boolean type).
6147
6148 elsif Root_Type (Typ) = Standard_Boolean then
6149 Else_Expr :=
6150 Convert_To (Typ, New_Occurrence_Of (Standard_True, Sloc (N)));
6151 Analyze_And_Resolve (Else_Expr, Typ);
6152 Append_To (Expressions (N), Else_Expr);
6153
6154 else
6155 Error_Msg_N ("can only omit ELSE expression in Boolean case", N);
6156 Append_To (Expressions (N), Error);
6157 end if;
6158
996ae0b0
RK		 6159 Set_Etype (N, Typ);
6160 Eval_Conditional_Expression (N);
6161 end Resolve_Conditional_Expression;
6162
6163 -----------------------------------------
6164 -- Resolve_Discrete_Subtype_Indication --
6165 -----------------------------------------
6166
6167 procedure Resolve_Discrete_Subtype_Indication
6168 (N : Node_Id;
6169 Typ : Entity_Id)
6170 is
6171 R : Node_Id;
6172 S : Entity_Id;
6173
6174 begin
6175 Analyze (Subtype_Mark (N));
6176 S := Entity (Subtype_Mark (N));
6177
6178 if Nkind (Constraint (N)) /= N_Range_Constraint then
6179 Error_Msg_N ("expect range constraint for discrete type", N);
6180 Set_Etype (N, Any_Type);
6181
6182 else
6183 R := Range_Expression (Constraint (N));
5c736541
RD		 6184
6185 if R = Error then
6186 return;
6187 end if;
6188
996ae0b0
RK		 6189 Analyze (R);
6190
6191 if Base_Type (S) /= Base_Type (Typ) then
6192 Error_Msg_NE
6193 ("expect subtype of }", N, First_Subtype (Typ));
6194
6195 -- Rewrite the constraint as a range of Typ
6196 -- to allow compilation to proceed further.
6197
6198 Set_Etype (N, Typ);
6199 Rewrite (Low_Bound (R),
6200 Make_Attribute_Reference (Sloc (Low_Bound (R)),
5cc9353d 6201 Prefix => New_Occurrence_Of (Typ, Sloc (R)),
996ae0b0
RK		 6202 Attribute_Name => Name_First));
6203 Rewrite (High_Bound (R),
6204 Make_Attribute_Reference (Sloc (High_Bound (R)),
5cc9353d 6205 Prefix => New_Occurrence_Of (Typ, Sloc (R)),
996ae0b0
RK		 6206 Attribute_Name => Name_First));
6207
6208 else
6209 Resolve (R, Typ);
6210 Set_Etype (N, Etype (R));
6211
6212 -- Additionally, we must check that the bounds are compatible
6213 -- with the given subtype, which might be different from the
6214 -- type of the context.
6215
6216 Apply_Range_Check (R, S);
6217
6218 -- ??? If the above check statically detects a Constraint_Error
6219 -- it replaces the offending bound(s) of the range R with a
6220 -- Constraint_Error node. When the itype which uses these bounds
6221 -- is frozen the resulting call to Duplicate_Subexpr generates
6222 -- a new temporary for the bounds.
6223
6224 -- Unfortunately there are other itypes that are also made depend
6225 -- on these bounds, so when Duplicate_Subexpr is called they get
6226 -- a forward reference to the newly created temporaries and Gigi
6227 -- aborts on such forward references. This is probably sign of a
6228 -- more fundamental problem somewhere else in either the order of
6229 -- itype freezing or the way certain itypes are constructed.
6230
6231 -- To get around this problem we call Remove_Side_Effects right
6232 -- away if either bounds of R are a Constraint_Error.
6233
6234 declare
fbf5a39b
AC		 6235 L : constant Node_Id := Low_Bound (R);
6236 H : constant Node_Id := High_Bound (R);
996ae0b0
RK		 6237
6238 begin
6239 if Nkind (L) = N_Raise_Constraint_Error then
6240 Remove_Side_Effects (L);
6241 end if;
6242
6243 if Nkind (H) = N_Raise_Constraint_Error then
6244 Remove_Side_Effects (H);
6245 end if;
6246 end;
6247
6248 Check_Unset_Reference (Low_Bound (R));
6249 Check_Unset_Reference (High_Bound (R));
6250 end if;
6251 end if;
6252 end Resolve_Discrete_Subtype_Indication;
6253
6254 -------------------------
6255 -- Resolve_Entity_Name --
6256 -------------------------
6257
6258 -- Used to resolve identifiers and expanded names
6259
6260 procedure Resolve_Entity_Name (N : Node_Id; Typ : Entity_Id) is
6261 E : constant Entity_Id := Entity (N);
6262
6263 begin
07fc65c4
GB		 6264 -- If garbage from errors, set to Any_Type and return
6265
6266 if No (E) and then Total_Errors_Detected /= 0 then
6267 Set_Etype (N, Any_Type);
6268 return;
6269 end if;
6270
996ae0b0
RK		 6271 -- Replace named numbers by corresponding literals. Note that this is
6272 -- the one case where Resolve_Entity_Name must reset the Etype, since
6273 -- it is currently marked as universal.
6274
6275 if Ekind (E) = E_Named_Integer then
6276 Set_Etype (N, Typ);
6277 Eval_Named_Integer (N);
6278
6279 elsif Ekind (E) = E_Named_Real then
6280 Set_Etype (N, Typ);
6281 Eval_Named_Real (N);
6282
6989bc1f
AC		 6283 -- For enumeration literals, we need to make sure that a proper style
6284 -- check is done, since such literals are overloaded, and thus we did
6285 -- not do a style check during the first phase of analysis.
6286
6287 elsif Ekind (E) = E_Enumeration_Literal then
6288 Set_Entity_With_Style_Check (N, E);
6289 Eval_Entity_Name (N);
6290
e606088a 6291 -- Case of subtype name appearing as an operand in expression
996ae0b0
RK		 6292
6293 elsif Is_Type (E) then
e606088a
AC		 6294
6295 -- Allow use of subtype if it is a concurrent type where we are
6296 -- currently inside the body. This will eventually be expanded into a
6297 -- call to Self (for tasks) or _object (for protected objects). Any
6298 -- other use of a subtype is invalid.
6299
996ae0b0
RK		 6300 if Is_Concurrent_Type (E)
6301 and then In_Open_Scopes (E)
6302 then
6303 null;
e606088a 6304
308e6f3a 6305 -- Any other use is an error
e606088a 6306
996ae0b0
RK		 6307 else
6308 Error_Msg_N
758c442c 6309 ("invalid use of subtype mark in expression or call", N);
996ae0b0
RK		 6310 end if;
6311
6312 -- Check discriminant use if entity is discriminant in current scope,
6313 -- i.e. discriminant of record or concurrent type currently being
6314 -- analyzed. Uses in corresponding body are unrestricted.
6315
6316 elsif Ekind (E) = E_Discriminant
6317 and then Scope (E) = Current_Scope
6318 and then not Has_Completion (Current_Scope)
6319 then
6320 Check_Discriminant_Use (N);
6321
6322 -- A parameterless generic function cannot appear in a context that
6323 -- requires resolution.
6324
6325 elsif Ekind (E) = E_Generic_Function then
6326 Error_Msg_N ("illegal use of generic function", N);
6327
6328 elsif Ekind (E) = E_Out_Parameter
0ab80019 6329 and then Ada_Version = Ada_83
996ae0b0 6330 and then (Nkind (Parent (N)) in N_Op
19fb051c
AC		 6331 or else (Nkind (Parent (N)) = N_Assignment_Statement
6332 and then N = Expression (Parent (N)))
6333 or else Nkind (Parent (N)) = N_Explicit_Dereference)
996ae0b0
RK		 6334 then
6335 Error_Msg_N ("(Ada 83) illegal reading of out parameter", N);
6336
6337 -- In all other cases, just do the possible static evaluation
6338
6339 else
d81b4bfe
TQ		 6340 -- A deferred constant that appears in an expression must have a
6341 -- completion, unless it has been removed by in-place expansion of
6342 -- an aggregate.
996ae0b0
RK		 6343
6344 if Ekind (E) = E_Constant
6345 and then Comes_From_Source (E)
6346 and then No (Constant_Value (E))
6347 and then Is_Frozen (Etype (E))
45fc7ddb 6348 and then not In_Spec_Expression
996ae0b0
RK		 6349 and then not Is_Imported (E)
6350 then
996ae0b0
RK		 6351 if No_Initialization (Parent (E))
6352 or else (Present (Full_View (E))
6353 and then No_Initialization (Parent (Full_View (E))))
6354 then
6355 null;
6356 else
6357 Error_Msg_N (
6358 "deferred constant is frozen before completion", N);
6359 end if;
6360 end if;
6361
6362 Eval_Entity_Name (N);
6363 end if;
6364 end Resolve_Entity_Name;
6365
6366 -------------------
6367 -- Resolve_Entry --
6368 -------------------
6369
6370 procedure Resolve_Entry (Entry_Name : Node_Id) is
6371 Loc : constant Source_Ptr := Sloc (Entry_Name);
6372 Nam : Entity_Id;
6373 New_N : Node_Id;
6374 S : Entity_Id;
6375 Tsk : Entity_Id;
6376 E_Name : Node_Id;
6377 Index : Node_Id;
6378
6379 function Actual_Index_Type (E : Entity_Id) return Entity_Id;
6380 -- If the bounds of the entry family being called depend on task
6381 -- discriminants, build a new index subtype where a discriminant is
6382 -- replaced with the value of the discriminant of the target task.
6383 -- The target task is the prefix of the entry name in the call.
6384
6385 -----------------------
6386 -- Actual_Index_Type --
6387 -----------------------
6388
6389 function Actual_Index_Type (E : Entity_Id) return Entity_Id is
fbf5a39b
AC		 6390 Typ : constant Entity_Id := Entry_Index_Type (E);
6391 Tsk : constant Entity_Id := Scope (E);
6392 Lo : constant Node_Id := Type_Low_Bound (Typ);
6393 Hi : constant Node_Id := Type_High_Bound (Typ);
996ae0b0
RK		 6394 New_T : Entity_Id;
6395
6396 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id;
6397 -- If the bound is given by a discriminant, replace with a reference
d81b4bfe
TQ		 6398 -- to the discriminant of the same name in the target task. If the
6399 -- entry name is the target of a requeue statement and the entry is
6400 -- in the current protected object, the bound to be used is the
008f6fd3 6401 -- discriminal of the object (see Apply_Range_Checks for details of
d81b4bfe 6402 -- the transformation).
996ae0b0
RK		 6403
6404 -----------------------------
6405 -- Actual_Discriminant_Ref --
6406 -----------------------------
6407
6408 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
fbf5a39b 6409 Typ : constant Entity_Id := Etype (Bound);
996ae0b0
RK		 6410 Ref : Node_Id;
6411
6412 begin
6413 Remove_Side_Effects (Bound);
6414
6415 if not Is_Entity_Name (Bound)
6416 or else Ekind (Entity (Bound)) /= E_Discriminant
6417 then
6418 return Bound;
6419
6420 elsif Is_Protected_Type (Tsk)
6421 and then In_Open_Scopes (Tsk)
6422 and then Nkind (Parent (Entry_Name)) = N_Requeue_Statement
6423 then
6ca9ec9c
AC		 6424 -- Note: here Bound denotes a discriminant of the corresponding
6425 -- record type tskV, whose discriminal is a formal of the
6426 -- init-proc tskVIP. What we want is the body discriminal,
6427 -- which is associated to the discriminant of the original
6428 -- concurrent type tsk.
6429
5a153b27
AC		 6430 return New_Occurrence_Of
6431 (Find_Body_Discriminal (Entity (Bound)), Loc);
996ae0b0
RK		 6432
6433 else
6434 Ref :=
6435 Make_Selected_Component (Loc,
6436 Prefix => New_Copy_Tree (Prefix (Prefix (Entry_Name))),
6437 Selector_Name => New_Occurrence_Of (Entity (Bound), Loc));
6438 Analyze (Ref);
6439 Resolve (Ref, Typ);
6440 return Ref;
6441 end if;
6442 end Actual_Discriminant_Ref;
6443
6444 -- Start of processing for Actual_Index_Type
6445
6446 begin
6447 if not Has_Discriminants (Tsk)
19fb051c 6448 or else (not Is_Entity_Name (Lo) and then not Is_Entity_Name (Hi))
996ae0b0
RK		 6449 then
6450 return Entry_Index_Type (E);
6451
6452 else
6453 New_T := Create_Itype (Ekind (Typ), Parent (Entry_Name));
6454 Set_Etype (New_T, Base_Type (Typ));
6455 Set_Size_Info (New_T, Typ);
6456 Set_RM_Size (New_T, RM_Size (Typ));
6457 Set_Scalar_Range (New_T,
6458 Make_Range (Sloc (Entry_Name),
6459 Low_Bound => Actual_Discriminant_Ref (Lo),
6460 High_Bound => Actual_Discriminant_Ref (Hi)));
6461
6462 return New_T;
6463 end if;
6464 end Actual_Index_Type;
6465
6466 -- Start of processing of Resolve_Entry
6467
6468 begin
5cc9353d
RD		 6469 -- Find name of entry being called, and resolve prefix of name with its
6470 -- own type. The prefix can be overloaded, and the name and signature of
6471 -- the entry must be taken into account.
996ae0b0
RK		 6472
6473 if Nkind (Entry_Name) = N_Indexed_Component then
6474
6475 -- Case of dealing with entry family within the current tasks
6476
6477 E_Name := Prefix (Entry_Name);
6478
6479 else
6480 E_Name := Entry_Name;
6481 end if;
6482
6483 if Is_Entity_Name (E_Name) then
996ae0b0 6484
d81b4bfe
TQ		 6485 -- Entry call to an entry (or entry family) in the current task. This
6486 -- is legal even though the task will deadlock. Rewrite as call to
6487 -- current task.
996ae0b0 6488
d81b4bfe
TQ		 6489 -- This can also be a call to an entry in an enclosing task. If this
6490 -- is a single task, we have to retrieve its name, because the scope
6491 -- of the entry is the task type, not the object. If the enclosing
6492 -- task is a task type, the identity of the task is given by its own
6493 -- self variable.
6494
6495 -- Finally this can be a requeue on an entry of the same task or
6496 -- protected object.
996ae0b0
RK		 6497
6498 S := Scope (Entity (E_Name));
6499
6500 for J in reverse 0 .. Scope_Stack.Last loop
996ae0b0
RK		 6501 if Is_Task_Type (Scope_Stack.Table (J).Entity)
6502 and then not Comes_From_Source (S)
6503 then
6504 -- S is an enclosing task or protected object. The concurrent
6505 -- declaration has been converted into a type declaration, and
6506 -- the object itself has an object declaration that follows
6507 -- the type in the same declarative part.
6508
6509 Tsk := Next_Entity (S);
996ae0b0
RK		 6510 while Etype (Tsk) /= S loop
6511 Next_Entity (Tsk);
6512 end loop;
6513
6514 S := Tsk;
6515 exit;
6516
6517 elsif S = Scope_Stack.Table (J).Entity then
6518
6519 -- Call to current task. Will be transformed into call to Self
6520
6521 exit;
6522
6523 end if;
6524 end loop;
6525
6526 New_N :=
6527 Make_Selected_Component (Loc,
6528 Prefix => New_Occurrence_Of (S, Loc),
6529 Selector_Name =>
6530 New_Occurrence_Of (Entity (E_Name), Loc));
6531 Rewrite (E_Name, New_N);
6532 Analyze (E_Name);
6533
6534 elsif Nkind (Entry_Name) = N_Selected_Component
6535 and then Is_Overloaded (Prefix (Entry_Name))
6536 then
d81b4bfe 6537 -- Use the entry name (which must be unique at this point) to find
5cc9353d 6538 -- the prefix that returns the corresponding task/protected type.
996ae0b0
RK		 6539
6540 declare
fbf5a39b
AC		 6541 Pref : constant Node_Id := Prefix (Entry_Name);
6542 Ent : constant Entity_Id := Entity (Selector_Name (Entry_Name));
996ae0b0
RK		 6543 I : Interp_Index;
6544 It : Interp;
996ae0b0
RK		 6545
6546 begin
6547 Get_First_Interp (Pref, I, It);
996ae0b0 6548 while Present (It.Typ) loop
996ae0b0
RK		 6549 if Scope (Ent) = It.Typ then
6550 Set_Etype (Pref, It.Typ);
6551 exit;
6552 end if;
6553
6554 Get_Next_Interp (I, It);
6555 end loop;
6556 end;
6557 end if;
6558
6559 if Nkind (Entry_Name) = N_Selected_Component then
fbf5a39b 6560 Resolve (Prefix (Entry_Name));
996ae0b0
RK		 6561
6562 else pragma Assert (Nkind (Entry_Name) = N_Indexed_Component);
6563 Nam := Entity (Selector_Name (Prefix (Entry_Name)));
fbf5a39b 6564 Resolve (Prefix (Prefix (Entry_Name)));
996ae0b0
RK		 6565 Index := First (Expressions (Entry_Name));
6566 Resolve (Index, Entry_Index_Type (Nam));
6567
d81b4bfe
TQ		 6568 -- Up to this point the expression could have been the actual in a
6569 -- simple entry call, and be given by a named association.
996ae0b0
RK		 6570
6571 if Nkind (Index) = N_Parameter_Association then
6572 Error_Msg_N ("expect expression for entry index", Index);
6573 else
6574 Apply_Range_Check (Index, Actual_Index_Type (Nam));
6575 end if;
6576 end if;
996ae0b0
RK		 6577 end Resolve_Entry;
6578
6579 ------------------------
6580 -- Resolve_Entry_Call --
6581 ------------------------
6582
6583 procedure Resolve_Entry_Call (N : Node_Id; Typ : Entity_Id) is
6584 Entry_Name : constant Node_Id := Name (N);
6585 Loc : constant Source_Ptr := Sloc (Entry_Name);
6586 Actuals : List_Id;
6587 First_Named : Node_Id;
6588 Nam : Entity_Id;
6589 Norm_OK : Boolean;
6590 Obj : Node_Id;
6591 Was_Over : Boolean;
6592
6593 begin
d81b4bfe
TQ		 6594 -- We kill all checks here, because it does not seem worth the effort to
6595 -- do anything better, an entry call is a big operation.
fbf5a39b
AC		 6596
6597 Kill_All_Checks;
6598
996ae0b0
RK		 6599 -- Processing of the name is similar for entry calls and protected
6600 -- operation calls. Once the entity is determined, we can complete
6601 -- the resolution of the actuals.
6602
6603 -- The selector may be overloaded, in the case of a protected object
6604 -- with overloaded functions. The type of the context is used for
6605 -- resolution.
6606
6607 if Nkind (Entry_Name) = N_Selected_Component
6608 and then Is_Overloaded (Selector_Name (Entry_Name))
6609 and then Typ /= Standard_Void_Type
6610 then
6611 declare
6612 I : Interp_Index;
6613 It : Interp;
6614
6615 begin
6616 Get_First_Interp (Selector_Name (Entry_Name), I, It);
996ae0b0 6617 while Present (It.Typ) loop
996ae0b0
RK		 6618 if Covers (Typ, It.Typ) then
6619 Set_Entity (Selector_Name (Entry_Name), It.Nam);
6620 Set_Etype (Entry_Name, It.Typ);
6621
6622 Generate_Reference (It.Typ, N, ' ');
6623 end if;
6624
6625 Get_Next_Interp (I, It);
6626 end loop;
6627 end;
6628 end if;
6629
6630 Resolve_Entry (Entry_Name);
6631
6632 if Nkind (Entry_Name) = N_Selected_Component then
6633
a77842bd 6634 -- Simple entry call
996ae0b0
RK		 6635
6636 Nam := Entity (Selector_Name (Entry_Name));
6637 Obj := Prefix (Entry_Name);
6638 Was_Over := Is_Overloaded (Selector_Name (Entry_Name));
6639
6640 else pragma Assert (Nkind (Entry_Name) = N_Indexed_Component);
6641
a77842bd 6642 -- Call to member of entry family
996ae0b0
RK		 6643
6644 Nam := Entity (Selector_Name (Prefix (Entry_Name)));
6645 Obj := Prefix (Prefix (Entry_Name));
6646 Was_Over := Is_Overloaded (Selector_Name (Prefix (Entry_Name)));
6647 end if;
6648
5cc9353d
RD		 6649 -- We cannot in general check the maximum depth of protected entry calls
6650 -- at compile time. But we can tell that any protected entry call at all
6651 -- violates a specified nesting depth of zero.
fbf5a39b
AC		 6652
6653 if Is_Protected_Type (Scope (Nam)) then
9f4fd324 6654 Check_Restriction (Max_Entry_Queue_Length, N);
fbf5a39b
AC		 6655 end if;
6656
996ae0b0 6657 -- Use context type to disambiguate a protected function that can be
5cc9353d
RD		 6658 -- called without actuals and that returns an array type, and where the
6659 -- argument list may be an indexing of the returned value.
996ae0b0
RK		 6660
6661 if Ekind (Nam) = E_Function
6662 and then Needs_No_Actuals (Nam)
6663 and then Present (Parameter_Associations (N))
6664 and then
6665 ((Is_Array_Type (Etype (Nam))
6666 and then Covers (Typ, Component_Type (Etype (Nam))))
6667
6668 or else (Is_Access_Type (Etype (Nam))
6669 and then Is_Array_Type (Designated_Type (Etype (Nam)))
19fb051c
AC		 6670 and then
6671 Covers
6672 (Typ,
6673 Component_Type (Designated_Type (Etype (Nam))))))
996ae0b0
RK		 6674 then
6675 declare
6676 Index_Node : Node_Id;
6677
6678 begin
6679 Index_Node :=
6680 Make_Indexed_Component (Loc,
6681 Prefix =>
19fb051c 6682 Make_Function_Call (Loc, Name => Relocate_Node (Entry_Name)),
996ae0b0
RK		 6683 Expressions => Parameter_Associations (N));
6684
5cc9353d
RD		 6685 -- Since we are correcting a node classification error made by the
6686 -- parser, we call Replace rather than Rewrite.
996ae0b0
RK		 6687
6688 Replace (N, Index_Node);
6689 Set_Etype (Prefix (N), Etype (Nam));
6690 Set_Etype (N, Typ);
6691 Resolve_Indexed_Component (N, Typ);
6692 return;
6693 end;
6694 end if;
6695
b7f17b20
ES		 6696 if Ekind_In (Nam, E_Entry, E_Entry_Family)
6697 and then Present (PPC_Wrapper (Nam))
6698 and then Current_Scope /= PPC_Wrapper (Nam)
6699 then
468ee96a 6700 -- Rewrite as call to the precondition wrapper, adding the task
5cc9353d
RD		 6701 -- object to the list of actuals. If the call is to a member of an
6702 -- entry family, include the index as well.
b7f17b20
ES		 6703
6704 declare
468ee96a 6705 New_Call : Node_Id;
b7f17b20 6706 New_Actuals : List_Id;
19fb051c 6707
b7f17b20
ES		 6708 begin
6709 New_Actuals := New_List (Obj);
3fd9f17c
AC		 6710
6711 if Nkind (Entry_Name) = N_Indexed_Component then
6712 Append_To (New_Actuals,
6713 New_Copy_Tree (First (Expressions (Entry_Name))));
6714 end if;
6715
b7f17b20 6716 Append_List (Parameter_Associations (N), New_Actuals);
468ee96a
AC		 6717 New_Call :=
6718 Make_Procedure_Call_Statement (Loc,
6719 Name =>
6720 New_Occurrence_Of (PPC_Wrapper (Nam), Loc),
6721 Parameter_Associations => New_Actuals);
b7f17b20
ES		 6722 Rewrite (N, New_Call);
6723 Analyze_And_Resolve (N);
6724 return;
6725 end;
6726 end if;
6727
996ae0b0 6728 -- The operation name may have been overloaded. Order the actuals
5cc9353d
RD		 6729 -- according to the formals of the resolved entity, and set the return
6730 -- type to that of the operation.
996ae0b0
RK		 6731
6732 if Was_Over then
6733 Normalize_Actuals (N, Nam, False, Norm_OK);
6734 pragma Assert (Norm_OK);
fbf5a39b 6735 Set_Etype (N, Etype (Nam));
996ae0b0
RK		 6736 end if;
6737
6738 Resolve_Actuals (N, Nam);
ae6ede77
AC		 6739
6740 -- Create a call reference to the entry
6741
6742 Generate_Reference (Nam, Entry_Name, 's');
996ae0b0 6743
8a95f4e8 6744 if Ekind_In (Nam, E_Entry, E_Entry_Family) then
996ae0b0
RK		 6745 Check_Potentially_Blocking_Operation (N);
6746 end if;
6747
6748 -- Verify that a procedure call cannot masquerade as an entry
6749 -- call where an entry call is expected.
6750
6751 if Ekind (Nam) = E_Procedure then
996ae0b0
RK		 6752 if Nkind (Parent (N)) = N_Entry_Call_Alternative
6753 and then N = Entry_Call_Statement (Parent (N))
6754 then
6755 Error_Msg_N ("entry call required in select statement", N);
6756
6757 elsif Nkind (Parent (N)) = N_Triggering_Alternative
6758 and then N = Triggering_Statement (Parent (N))
6759 then
6760 Error_Msg_N ("triggering statement cannot be procedure call", N);
6761
6762 elsif Ekind (Scope (Nam)) = E_Task_Type
6763 and then not In_Open_Scopes (Scope (Nam))
6764 then
758c442c 6765 Error_Msg_N ("task has no entry with this name", Entry_Name);
996ae0b0
RK		 6766 end if;
6767 end if;
6768
d81b4bfe
TQ		 6769 -- After resolution, entry calls and protected procedure calls are
6770 -- changed into entry calls, for expansion. The structure of the node
6771 -- does not change, so it can safely be done in place. Protected
6772 -- function calls must keep their structure because they are
6773 -- subexpressions.
996ae0b0
RK		 6774
6775 if Ekind (Nam) /= E_Function then
6776
6777 -- A protected operation that is not a function may modify the
d81b4bfe
TQ		 6778 -- corresponding object, and cannot apply to a constant. If this
6779 -- is an internal call, the prefix is the type itself.
996ae0b0
RK		 6780
6781 if Is_Protected_Type (Scope (Nam))
6782 and then not Is_Variable (Obj)
6783 and then (not Is_Entity_Name (Obj)
6784 or else not Is_Type (Entity (Obj)))
6785 then
6786 Error_Msg_N
6787 ("prefix of protected procedure or entry call must be variable",
6788 Entry_Name);
6789 end if;
6790
6791 Actuals := Parameter_Associations (N);
6792 First_Named := First_Named_Actual (N);
6793
6794 Rewrite (N,
6795 Make_Entry_Call_Statement (Loc,
6796 Name => Entry_Name,
6797 Parameter_Associations => Actuals));
6798
6799 Set_First_Named_Actual (N, First_Named);
6800 Set_Analyzed (N, True);
6801
6802 -- Protected functions can return on the secondary stack, in which
1420b484 6803 -- case we must trigger the transient scope mechanism.
996ae0b0 6804
da94696d 6805 elsif Full_Expander_Active
996ae0b0
RK		 6806 and then Requires_Transient_Scope (Etype (Nam))
6807 then
0669bebe 6808 Establish_Transient_Scope (N, Sec_Stack => True);
996ae0b0 6809 end if;
996ae0b0
RK		 6810 end Resolve_Entry_Call;
6811
6812 -------------------------
6813 -- Resolve_Equality_Op --
6814 -------------------------
6815
d81b4bfe
TQ		 6816 -- Both arguments must have the same type, and the boolean context does
6817 -- not participate in the resolution. The first pass verifies that the
6818 -- interpretation is not ambiguous, and the type of the left argument is
6819 -- correctly set, or is Any_Type in case of ambiguity. If both arguments
6820 -- are strings or aggregates, allocators, or Null, they are ambiguous even
6821 -- though they carry a single (universal) type. Diagnose this case here.
996ae0b0
RK		 6822
6823 procedure Resolve_Equality_Op (N : Node_Id; Typ : Entity_Id) is
6824 L : constant Node_Id := Left_Opnd (N);
6825 R : constant Node_Id := Right_Opnd (N);
6826 T : Entity_Id := Find_Unique_Type (L, R);
6827
a8930b80
AC		 6828 procedure Check_Conditional_Expression (Cond : Node_Id);
6829 -- The resolution rule for conditional expressions requires that each
6830 -- such must have a unique type. This means that if several dependent
6831 -- expressions are of a non-null anonymous access type, and the context
6832 -- does not impose an expected type (as can be the case in an equality
6833 -- operation) the expression must be rejected.
6834
996ae0b0
RK		 6835 function Find_Unique_Access_Type return Entity_Id;
6836 -- In the case of allocators, make a last-ditch attempt to find a single
6837 -- access type with the right designated type. This is semantically
6838 -- dubious, and of no interest to any real code, but c48008a makes it
6839 -- all worthwhile.
6840
a8930b80
AC		 6841 ----------------------------------
6842 -- Check_Conditional_Expression --
6843 ----------------------------------
6844
6845 procedure Check_Conditional_Expression (Cond : Node_Id) is
6846 Then_Expr : Node_Id;
6847 Else_Expr : Node_Id;
6848
6849 begin
6850 if Nkind (Cond) = N_Conditional_Expression then
6851 Then_Expr := Next (First (Expressions (Cond)));
6852 Else_Expr := Next (Then_Expr);
6853
6854 if Nkind (Then_Expr) /= N_Null
6855 and then Nkind (Else_Expr) /= N_Null
6856 then
6857 Error_Msg_N
6858 ("cannot determine type of conditional expression", Cond);
6859 end if;
6860 end if;
6861 end Check_Conditional_Expression;
6862
996ae0b0
RK		 6863 -----------------------------
6864 -- Find_Unique_Access_Type --
6865 -----------------------------
6866
6867 function Find_Unique_Access_Type return Entity_Id is
6868 Acc : Entity_Id;
6869 E : Entity_Id;
1420b484 6870 S : Entity_Id;
996ae0b0
RK		 6871
6872 begin
6873 if Ekind (Etype (R)) = E_Allocator_Type then
6874 Acc := Designated_Type (Etype (R));
996ae0b0
RK		 6875 elsif Ekind (Etype (L)) = E_Allocator_Type then
6876 Acc := Designated_Type (Etype (L));
996ae0b0
RK		 6877 else
6878 return Empty;
6879 end if;
6880
1420b484 6881 S := Current_Scope;
996ae0b0
RK		 6882 while S /= Standard_Standard loop
6883 E := First_Entity (S);
996ae0b0 6884 while Present (E) loop
996ae0b0
RK		 6885 if Is_Type (E)
6886 and then Is_Access_Type (E)
6887 and then Ekind (E) /= E_Allocator_Type
6888 and then Designated_Type (E) = Base_Type (Acc)
6889 then
6890 return E;
6891 end if;
6892
6893 Next_Entity (E);
6894 end loop;
6895
6896 S := Scope (S);
6897 end loop;
6898
6899 return Empty;
6900 end Find_Unique_Access_Type;
6901
6902 -- Start of processing for Resolve_Equality_Op
6903
6904 begin
6905 Set_Etype (N, Base_Type (Typ));
6906 Generate_Reference (T, N, ' ');
6907
6908 if T = Any_Fixed then
6909 T := Unique_Fixed_Point_Type (L);
6910 end if;
6911
6912 if T /= Any_Type then
19fb051c
AC		 6913 if T = Any_String or else
6914 T = Any_Composite or else
6915 T = Any_Character
996ae0b0 6916 then
996ae0b0
RK		 6917 if T = Any_Character then
6918 Ambiguous_Character (L);
6919 else
6920 Error_Msg_N ("ambiguous operands for equality", N);
6921 end if;
6922
6923 Set_Etype (N, Any_Type);
6924 return;
6925
6926 elsif T = Any_Access
964f13da 6927 or else Ekind_In (T, E_Allocator_Type, E_Access_Attribute_Type)
996ae0b0
RK		 6928 then
6929 T := Find_Unique_Access_Type;
6930
6931 if No (T) then
6932 Error_Msg_N ("ambiguous operands for equality", N);
6933 Set_Etype (N, Any_Type);
6934 return;
6935 end if;
a8930b80
AC		 6936
6937 -- Conditional expressions must have a single type, and if the
6938 -- context does not impose one the dependent expressions cannot
6939 -- be anonymous access types.
6940
6941 elsif Ada_Version >= Ada_2012
ae2aa109
AC		 6942 and then Ekind_In (Etype (L), E_Anonymous_Access_Type,
6943 E_Anonymous_Access_Subprogram_Type)
6944 and then Ekind_In (Etype (R), E_Anonymous_Access_Type,
6945 E_Anonymous_Access_Subprogram_Type)
a8930b80
AC		 6946 then
6947 Check_Conditional_Expression (L);
6948 Check_Conditional_Expression (R);
996ae0b0
RK		 6949 end if;
6950
996ae0b0
RK		 6951 Resolve (L, T);
6952 Resolve (R, T);
fbf5a39b 6953
2ba431e5
YM		 6954 -- In SPARK, equality operators = and /= for array types other than
6955 -- String are only defined when, for each index position, the
6956 -- operands have equal static bounds.
b0186f71 6957
975c6896 6958 if Is_Array_Type (T) then
7b98672f
YM		 6959 -- Protect call to Matching_Static_Array_Bounds to avoid costly
6960 -- operation if not needed.
6961
6962 if Restriction_Check_Required (SPARK)
6963 and then Base_Type (T) /= Standard_String
975c6896
YM		 6964 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
6965 and then Etype (L) /= Any_Composite -- or else L in error
6966 and then Etype (R) /= Any_Composite -- or else R in error
6967 and then not Matching_Static_Array_Bounds (Etype (L), Etype (R))
6968 then
6969 Check_SPARK_Restriction
6970 ("array types should have matching static bounds", N);
6971 end if;
b0186f71
AC		 6972 end if;
6973
0669bebe
GB		 6974 -- If the unique type is a class-wide type then it will be expanded
6975 -- into a dispatching call to the predefined primitive. Therefore we
6976 -- check here for potential violation of such restriction.
6977
6978 if Is_Class_Wide_Type (T) then
6979 Check_Restriction (No_Dispatching_Calls, N);
6980 end if;
6981
fbf5a39b
AC		 6982 if Warn_On_Redundant_Constructs
6983 and then Comes_From_Source (N)
6984 and then Is_Entity_Name (R)
6985 and then Entity (R) = Standard_True
6986 and then Comes_From_Source (R)
6987 then
305caf42
AC		 6988 Error_Msg_N -- CODEFIX
6989 ("?comparison with True is redundant!", R);
fbf5a39b
AC		 6990 end if;
6991
996ae0b0
RK		 6992 Check_Unset_Reference (L);
6993 Check_Unset_Reference (R);
fbf5a39b 6994 Generate_Operator_Reference (N, T);
fad0600d 6995 Check_Low_Bound_Tested (N);
996ae0b0
RK		 6996
6997 -- If this is an inequality, it may be the implicit inequality
6998 -- created for a user-defined operation, in which case the corres-
6999 -- ponding equality operation is not intrinsic, and the operation
7000 -- cannot be constant-folded. Else fold.
7001
7002 if Nkind (N) = N_Op_Eq
7003 or else Comes_From_Source (Entity (N))
7004 or else Ekind (Entity (N)) = E_Operator
7005 or else Is_Intrinsic_Subprogram
19fb051c 7006 (Corresponding_Equality (Entity (N)))
996ae0b0 7007 then
dec6faf1 7008 Analyze_Dimension (N);
996ae0b0 7009 Eval_Relational_Op (N);
45fc7ddb 7010
996ae0b0 7011 elsif Nkind (N) = N_Op_Ne
0669bebe 7012 and then Is_Abstract_Subprogram (Entity (N))
996ae0b0
RK		 7013 then
7014 Error_Msg_NE ("cannot call abstract subprogram &!", N, Entity (N));
7015 end if;
758c442c 7016
d81b4bfe
TQ		 7017 -- Ada 2005: If one operand is an anonymous access type, convert the
7018 -- other operand to it, to ensure that the underlying types match in
7019 -- the back-end. Same for access_to_subprogram, and the conversion
7020 -- verifies that the types are subtype conformant.
b7d1f17f 7021
d81b4bfe
TQ		 7022 -- We apply the same conversion in the case one of the operands is a
7023 -- private subtype of the type of the other.
c8ef728f 7024
b7d1f17f
HK		 7025 -- Why the Expander_Active test here ???
7026
11fa950b 7027 if Full_Expander_Active
b7d1f17f 7028 and then
964f13da
RD		 7029 (Ekind_In (T, E_Anonymous_Access_Type,
7030 E_Anonymous_Access_Subprogram_Type)
b7d1f17f 7031 or else Is_Private_Type (T))
c8ef728f
ES		 7032 then
7033 if Etype (L) /= T then
7034 Rewrite (L,
7035 Make_Unchecked_Type_Conversion (Sloc (L),
7036 Subtype_Mark => New_Occurrence_Of (T, Sloc (L)),
7037 Expression => Relocate_Node (L)));
7038 Analyze_And_Resolve (L, T);
7039 end if;
7040
7041 if (Etype (R)) /= T then
7042 Rewrite (R,
7043 Make_Unchecked_Type_Conversion (Sloc (R),
7044 Subtype_Mark => New_Occurrence_Of (Etype (L), Sloc (R)),
7045 Expression => Relocate_Node (R)));
7046 Analyze_And_Resolve (R, T);
7047 end if;
7048 end if;
996ae0b0
RK		 7049 end if;
7050 end Resolve_Equality_Op;
7051
7052 ----------------------------------
7053 -- Resolve_Explicit_Dereference --
7054 ----------------------------------
7055
7056 procedure Resolve_Explicit_Dereference (N : Node_Id; Typ : Entity_Id) is
bc5f3720
RD		 7057 Loc : constant Source_Ptr := Sloc (N);
7058 New_N : Node_Id;
7059 P : constant Node_Id := Prefix (N);
7060 I : Interp_Index;
7061 It : Interp;
996ae0b0
RK		 7062
7063 begin
c8ef728f 7064 Check_Fully_Declared_Prefix (Typ, P);
996ae0b0
RK		 7065
7066 if Is_Overloaded (P) then
7067
758c442c
GD		 7068 -- Use the context type to select the prefix that has the correct
7069 -- designated type.
996ae0b0
RK		 7070
7071 Get_First_Interp (P, I, It);
7072 while Present (It.Typ) loop
7073 exit when Is_Access_Type (It.Typ)
7074 and then Covers (Typ, Designated_Type (It.Typ));
996ae0b0
RK		 7075 Get_Next_Interp (I, It);
7076 end loop;
7077
bc5f3720
RD		 7078 if Present (It.Typ) then
7079 Resolve (P, It.Typ);
7080 else
758c442c
GD		 7081 -- If no interpretation covers the designated type of the prefix,
7082 -- this is the pathological case where not all implementations of
7083 -- the prefix allow the interpretation of the node as a call. Now
7084 -- that the expected type is known, Remove other interpretations
7085 -- from prefix, rewrite it as a call, and resolve again, so that
7086 -- the proper call node is generated.
bc5f3720
RD		 7087
7088 Get_First_Interp (P, I, It);
7089 while Present (It.Typ) loop
7090 if Ekind (It.Typ) /= E_Access_Subprogram_Type then
7091 Remove_Interp (I);
7092 end if;
7093
7094 Get_Next_Interp (I, It);
7095 end loop;
7096
7097 New_N :=
7098 Make_Function_Call (Loc,
7099 Name =>
7100 Make_Explicit_Dereference (Loc,
7101 Prefix => P),
7102 Parameter_Associations => New_List);
7103
7104 Save_Interps (N, New_N);
7105 Rewrite (N, New_N);
7106 Analyze_And_Resolve (N, Typ);
7107 return;
7108 end if;
7109
996ae0b0
RK		 7110 Set_Etype (N, Designated_Type (It.Typ));
7111
7112 else
fbf5a39b 7113 Resolve (P);
996ae0b0
RK		 7114 end if;
7115
7116 if Is_Access_Type (Etype (P)) then
7117 Apply_Access_Check (N);
7118 end if;
7119
758c442c
GD		 7120 -- If the designated type is a packed unconstrained array type, and the
7121 -- explicit dereference is not in the context of an attribute reference,
7122 -- then we must compute and set the actual subtype, since it is needed
7123 -- by Gigi. The reason we exclude the attribute case is that this is
7124 -- handled fine by Gigi, and in fact we use such attributes to build the
7125 -- actual subtype. We also exclude generated code (which builds actual
7126 -- subtypes directly if they are needed).
996ae0b0
RK		 7127
7128 if Is_Array_Type (Etype (N))
7129 and then Is_Packed (Etype (N))
7130 and then not Is_Constrained (Etype (N))
7131 and then Nkind (Parent (N)) /= N_Attribute_Reference
7132 and then Comes_From_Source (N)
7133 then
7134 Set_Etype (N, Get_Actual_Subtype (N));
7135 end if;
7136
09494c32
AC		 7137 -- Note: No Eval processing is required for an explicit dereference,
7138 -- because such a name can never be static.
996ae0b0
RK		 7139
7140 end Resolve_Explicit_Dereference;
7141
955871d3
AC		 7142 -------------------------------------
7143 -- Resolve_Expression_With_Actions --
7144 -------------------------------------
7145
7146 procedure Resolve_Expression_With_Actions (N : Node_Id; Typ : Entity_Id) is
7147 begin
7148 Set_Etype (N, Typ);
7149 end Resolve_Expression_With_Actions;
7150
996ae0b0
RK		 7151 -------------------------------
7152 -- Resolve_Indexed_Component --
7153 -------------------------------
7154
7155 procedure Resolve_Indexed_Component (N : Node_Id; Typ : Entity_Id) is
7156 Name : constant Node_Id := Prefix (N);
7157 Expr : Node_Id;
7158 Array_Type : Entity_Id := Empty; -- to prevent junk warning
7159 Index : Node_Id;
7160
7161 begin
7162 if Is_Overloaded (Name) then
7163
758c442c
GD		 7164 -- Use the context type to select the prefix that yields the correct
7165 -- component type.
996ae0b0
RK		 7166
7167 declare
7168 I : Interp_Index;
7169 It : Interp;
7170 I1 : Interp_Index := 0;
7171 P : constant Node_Id := Prefix (N);
7172 Found : Boolean := False;
7173
7174 begin
7175 Get_First_Interp (P, I, It);
996ae0b0 7176 while Present (It.Typ) loop
996ae0b0
RK		 7177 if (Is_Array_Type (It.Typ)
7178 and then Covers (Typ, Component_Type (It.Typ)))
7179 or else (Is_Access_Type (It.Typ)
7180 and then Is_Array_Type (Designated_Type (It.Typ))
19fb051c
AC		 7181 and then
7182 Covers
7183 (Typ,
7184 Component_Type (Designated_Type (It.Typ))))
996ae0b0
RK		 7185 then
7186 if Found then
7187 It := Disambiguate (P, I1, I, Any_Type);
7188
7189 if It = No_Interp then
7190 Error_Msg_N ("ambiguous prefix for indexing", N);
7191 Set_Etype (N, Typ);
7192 return;
7193
7194 else
7195 Found := True;
7196 Array_Type := It.Typ;
7197 I1 := I;
7198 end if;
7199
7200 else
7201 Found := True;
7202 Array_Type := It.Typ;
7203 I1 := I;
7204 end if;
7205 end if;
7206
7207 Get_Next_Interp (I, It);
7208 end loop;
7209 end;
7210
7211 else
7212 Array_Type := Etype (Name);
7213 end if;
7214
7215 Resolve (Name, Array_Type);
7216 Array_Type := Get_Actual_Subtype_If_Available (Name);
7217
7218 -- If prefix is access type, dereference to get real array type.
7219 -- Note: we do not apply an access check because the expander always
7220 -- introduces an explicit dereference, and the check will happen there.
7221
7222 if Is_Access_Type (Array_Type) then
7223 Array_Type := Designated_Type (Array_Type);
7224 end if;
7225
a77842bd 7226 -- If name was overloaded, set component type correctly now
f3d57416 7227 -- If a misplaced call to an entry family (which has no index types)
b7d1f17f 7228 -- return. Error will be diagnosed from calling context.
996ae0b0 7229
b7d1f17f
HK		 7230 if Is_Array_Type (Array_Type) then
7231 Set_Etype (N, Component_Type (Array_Type));
7232 else
7233 return;
7234 end if;
996ae0b0
RK		 7235
7236 Index := First_Index (Array_Type);
7237 Expr := First (Expressions (N));
7238
758c442c
GD		 7239 -- The prefix may have resolved to a string literal, in which case its
7240 -- etype has a special representation. This is only possible currently
7241 -- if the prefix is a static concatenation, written in functional
7242 -- notation.
996ae0b0
RK		 7243
7244 if Ekind (Array_Type) = E_String_Literal_Subtype then
7245 Resolve (Expr, Standard_Positive);
7246
7247 else
7248 while Present (Index) and Present (Expr) loop
7249 Resolve (Expr, Etype (Index));
7250 Check_Unset_Reference (Expr);
7251
7252 if Is_Scalar_Type (Etype (Expr)) then
7253 Apply_Scalar_Range_Check (Expr, Etype (Index));
7254 else
7255 Apply_Range_Check (Expr, Get_Actual_Subtype (Index));
7256 end if;
7257
7258 Next_Index (Index);
7259 Next (Expr);
7260 end loop;
7261 end if;
7262
dec6faf1
AC		 7263 Analyze_Dimension (N);
7264
0669bebe
GB		 7265 -- Do not generate the warning on suspicious index if we are analyzing
7266 -- package Ada.Tags; otherwise we will report the warning with the
7267 -- Prims_Ptr field of the dispatch table.
7268
7269 if Scope (Etype (Prefix (N))) = Standard_Standard
7270 or else not
7271 Is_RTU (Cunit_Entity (Get_Source_Unit (Etype (Prefix (N)))),
7272 Ada_Tags)
7273 then
7274 Warn_On_Suspicious_Index (Name, First (Expressions (N)));
7275 Eval_Indexed_Component (N);
7276 end if;
c28408b7
RD		 7277
7278 -- If the array type is atomic, and is packed, and we are in a left side
7279 -- context, then this is worth a warning, since we have a situation
7280 -- where the access to the component may cause extra read/writes of
7281 -- the atomic array object, which could be considered unexpected.
7282
7283 if Nkind (N) = N_Indexed_Component
7284 and then (Is_Atomic (Array_Type)
7285 or else (Is_Entity_Name (Prefix (N))
7286 and then Is_Atomic (Entity (Prefix (N)))))
7287 and then Is_Bit_Packed_Array (Array_Type)
7288 and then Is_LHS (N)
7289 then
7290 Error_Msg_N ("?assignment to component of packed atomic array",
7291 Prefix (N));
7292 Error_Msg_N ("?\may cause unexpected accesses to atomic object",
7293 Prefix (N));
7294 end if;
996ae0b0
RK		 7295 end Resolve_Indexed_Component;
7296
7297 -----------------------------
7298 -- Resolve_Integer_Literal --
7299 -----------------------------
7300
7301 procedure Resolve_Integer_Literal (N : Node_Id; Typ : Entity_Id) is
7302 begin
7303 Set_Etype (N, Typ);
7304 Eval_Integer_Literal (N);
7305 end Resolve_Integer_Literal;
7306
15ce9ca2
AC		 7307 --------------------------------
7308 -- Resolve_Intrinsic_Operator --
7309 --------------------------------
996ae0b0
RK		 7310
7311 procedure Resolve_Intrinsic_Operator (N : Node_Id; Typ : Entity_Id) is
bb481772
AC		 7312 Btyp : constant Entity_Id := Base_Type (Underlying_Type (Typ));
7313 Op : Entity_Id;
7314 Orig_Op : constant Entity_Id := Entity (N);
7315 Arg1 : Node_Id;
7316 Arg2 : Node_Id;
996ae0b0 7317
78efd712
AC		 7318 function Convert_Operand (Opnd : Node_Id) return Node_Id;
7319 -- If the operand is a literal, it cannot be the expression in a
7320 -- conversion. Use a qualified expression instead.
7321
7322 function Convert_Operand (Opnd : Node_Id) return Node_Id is
7323 Loc : constant Source_Ptr := Sloc (Opnd);
7324 Res : Node_Id;
7325 begin
7326 if Nkind_In (Opnd, N_Integer_Literal, N_Real_Literal) then
7327 Res :=
7328 Make_Qualified_Expression (Loc,
7329 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
7330 Expression => Relocate_Node (Opnd));
7331 Analyze (Res);
7332
7333 else
7334 Res := Unchecked_Convert_To (Btyp, Opnd);
7335 end if;
7336
7337 return Res;
7338 end Convert_Operand;
7339
d72e7628 7340 -- Start of processing for Resolve_Intrinsic_Operator
7109f4f5 7341
996ae0b0 7342 begin
305caf42
AC		 7343 -- We must preserve the original entity in a generic setting, so that
7344 -- the legality of the operation can be verified in an instance.
7345
11fa950b 7346 if not Full_Expander_Active then
305caf42
AC		 7347 return;
7348 end if;
7349
996ae0b0 7350 Op := Entity (N);
996ae0b0
RK		 7351 while Scope (Op) /= Standard_Standard loop
7352 Op := Homonym (Op);
7353 pragma Assert (Present (Op));
7354 end loop;
7355
7356 Set_Entity (N, Op);
af152989 7357 Set_Is_Overloaded (N, False);
996ae0b0 7358
7109f4f5
AC		 7359 -- If the result or operand types are private, rewrite with unchecked
7360 -- conversions on the operands and the result, to expose the proper
7361 -- underlying numeric type.
996ae0b0 7362
7109f4f5
AC		 7363 if Is_Private_Type (Typ)
7364 or else Is_Private_Type (Etype (Left_Opnd (N)))
7365 or else Is_Private_Type (Etype (Right_Opnd (N)))
7366 then
78efd712
AC		 7367 Arg1 := Convert_Operand (Left_Opnd (N));
7368 -- Unchecked_Convert_To (Btyp, Left_Opnd (N));
aeae67ed 7369 -- What on earth is this commented out fragment of code???
fbf5a39b
AC		 7370
7371 if Nkind (N) = N_Op_Expon then
7372 Arg2 := Unchecked_Convert_To (Standard_Integer, Right_Opnd (N));
7373 else
78efd712 7374 Arg2 := Convert_Operand (Right_Opnd (N));
fbf5a39b
AC		 7375 end if;
7376
bb481772
AC		 7377 if Nkind (Arg1) = N_Type_Conversion then
7378 Save_Interps (Left_Opnd (N), Expression (Arg1));
7379 end if;
7380
7381 if Nkind (Arg2) = N_Type_Conversion then
7382 Save_Interps (Right_Opnd (N), Expression (Arg2));
7383 end if;
996ae0b0 7384
fbf5a39b
AC		 7385 Set_Left_Opnd (N, Arg1);
7386 Set_Right_Opnd (N, Arg2);
7387
7388 Set_Etype (N, Btyp);
7389 Rewrite (N, Unchecked_Convert_To (Typ, N));
7390 Resolve (N, Typ);
7391
7392 elsif Typ /= Etype (Left_Opnd (N))
7393 or else Typ /= Etype (Right_Opnd (N))
7394 then
d81b4bfe 7395 -- Add explicit conversion where needed, and save interpretations in
bb481772
AC		 7396 -- case operands are overloaded. If the context is a VMS operation,
7397 -- assert that the conversion is legal (the operands have the proper
7398 -- types to select the VMS intrinsic). Note that in rare cases the
7399 -- VMS operators may be visible, but the default System is being used
7400 -- and Address is a private type.
fbf5a39b 7401
af152989 7402 Arg1 := Convert_To (Typ, Left_Opnd (N));
fbf5a39b
AC		 7403 Arg2 := Convert_To (Typ, Right_Opnd (N));
7404
7405 if Nkind (Arg1) = N_Type_Conversion then
7406 Save_Interps (Left_Opnd (N), Expression (Arg1));
bb481772
AC		 7407
7408 if Is_VMS_Operator (Orig_Op) then
7409 Set_Conversion_OK (Arg1);
7410 end if;
af152989
AC		 7411 else
7412 Save_Interps (Left_Opnd (N), Arg1);
fbf5a39b
AC		 7413 end if;
7414
7415 if Nkind (Arg2) = N_Type_Conversion then
7416 Save_Interps (Right_Opnd (N), Expression (Arg2));
bb481772
AC		 7417
7418 if Is_VMS_Operator (Orig_Op) then
7419 Set_Conversion_OK (Arg2);
7420 end if;
af152989 7421 else
0ab80019 7422 Save_Interps (Right_Opnd (N), Arg2);
fbf5a39b
AC		 7423 end if;
7424
7425 Rewrite (Left_Opnd (N), Arg1);
7426 Rewrite (Right_Opnd (N), Arg2);
7427 Analyze (Arg1);
7428 Analyze (Arg2);
7429 Resolve_Arithmetic_Op (N, Typ);
7430
7431 else
7432 Resolve_Arithmetic_Op (N, Typ);
7433 end if;
996ae0b0
RK		 7434 end Resolve_Intrinsic_Operator;
7435
fbf5a39b
AC		 7436 --------------------------------------
7437 -- Resolve_Intrinsic_Unary_Operator --
7438 --------------------------------------
7439
7440 procedure Resolve_Intrinsic_Unary_Operator
7441 (N : Node_Id;
7442 Typ : Entity_Id)
7443 is
7444 Btyp : constant Entity_Id := Base_Type (Underlying_Type (Typ));
7445 Op : Entity_Id;
7446 Arg2 : Node_Id;
7447
7448 begin
7449 Op := Entity (N);
fbf5a39b
AC		 7450 while Scope (Op) /= Standard_Standard loop
7451 Op := Homonym (Op);
7452 pragma Assert (Present (Op));
7453 end loop;
7454
7455 Set_Entity (N, Op);
7456
7457 if Is_Private_Type (Typ) then
7458 Arg2 := Unchecked_Convert_To (Btyp, Right_Opnd (N));
7459 Save_Interps (Right_Opnd (N), Expression (Arg2));
7460
7461 Set_Right_Opnd (N, Arg2);
7462
7463 Set_Etype (N, Btyp);
7464 Rewrite (N, Unchecked_Convert_To (Typ, N));
7465 Resolve (N, Typ);
7466
7467 else
7468 Resolve_Unary_Op (N, Typ);
7469 end if;
7470 end Resolve_Intrinsic_Unary_Operator;
7471
996ae0b0
RK		 7472 ------------------------
7473 -- Resolve_Logical_Op --
7474 ------------------------
7475
7476 procedure Resolve_Logical_Op (N : Node_Id; Typ : Entity_Id) is
7477 B_Typ : Entity_Id;
7478
7479 begin
f61580d4
AC		 7480 Check_No_Direct_Boolean_Operators (N);
7481
758c442c
GD		 7482 -- Predefined operations on scalar types yield the base type. On the
7483 -- other hand, logical operations on arrays yield the type of the
7484 -- arguments (and the context).
996ae0b0
RK		 7485
7486 if Is_Array_Type (Typ) then
7487 B_Typ := Typ;
7488 else
7489 B_Typ := Base_Type (Typ);
7490 end if;
7491
001c7783
AC		 7492 -- OK if this is a VMS-specific intrinsic operation
7493
7494 if Is_VMS_Operator (Entity (N)) then
7495 null;
7496
996ae0b0
RK		 7497 -- The following test is required because the operands of the operation
7498 -- may be literals, in which case the resulting type appears to be
7499 -- compatible with a signed integer type, when in fact it is compatible
7500 -- only with modular types. If the context itself is universal, the
7501 -- operation is illegal.
7502
001c7783 7503 elsif not Valid_Boolean_Arg (Typ) then
996ae0b0
RK		 7504 Error_Msg_N ("invalid context for logical operation", N);
7505 Set_Etype (N, Any_Type);
7506 return;
7507
7508 elsif Typ = Any_Modular then
7509 Error_Msg_N
7510 ("no modular type available in this context", N);
7511 Set_Etype (N, Any_Type);
7512 return;
19fb051c 7513
07fc65c4
GB		 7514 elsif Is_Modular_Integer_Type (Typ)
7515 and then Etype (Left_Opnd (N)) = Universal_Integer
7516 and then Etype (Right_Opnd (N)) = Universal_Integer
7517 then
7518 Check_For_Visible_Operator (N, B_Typ);
996ae0b0
RK		 7519 end if;
7520
f2d10a02
AC		 7521 -- Replace AND by AND THEN, or OR by OR ELSE, if Short_Circuit_And_Or
7522 -- is active and the result type is standard Boolean (do not mess with
7523 -- ops that return a nonstandard Boolean type, because something strange
7524 -- is going on).
7525
7526 -- Note: you might expect this replacement to be done during expansion,
7527 -- but that doesn't work, because when the pragma Short_Circuit_And_Or
7528 -- is used, no part of the right operand of an "and" or "or" operator
7529 -- should be executed if the left operand would short-circuit the
7530 -- evaluation of the corresponding "and then" or "or else". If we left
7531 -- the replacement to expansion time, then run-time checks associated
7532 -- with such operands would be evaluated unconditionally, due to being
af89615f 7533 -- before the condition prior to the rewriting as short-circuit forms
f2d10a02
AC		 7534 -- during expansion.
7535
7536 if Short_Circuit_And_Or
7537 and then B_Typ = Standard_Boolean
7538 and then Nkind_In (N, N_Op_And, N_Op_Or)
7539 then
7540 if Nkind (N) = N_Op_And then
7541 Rewrite (N,
7542 Make_And_Then (Sloc (N),
7543 Left_Opnd => Relocate_Node (Left_Opnd (N)),
7544 Right_Opnd => Relocate_Node (Right_Opnd (N))));
7545 Analyze_And_Resolve (N, B_Typ);
7546
7547 -- Case of OR changed to OR ELSE
7548
7549 else
7550 Rewrite (N,
7551 Make_Or_Else (Sloc (N),
7552 Left_Opnd => Relocate_Node (Left_Opnd (N)),
7553 Right_Opnd => Relocate_Node (Right_Opnd (N))));
7554 Analyze_And_Resolve (N, B_Typ);
7555 end if;
7556
7557 -- Return now, since analysis of the rewritten ops will take care of
7558 -- other reference bookkeeping and expression folding.
7559
7560 return;
7561 end if;
7562
996ae0b0
RK		 7563 Resolve (Left_Opnd (N), B_Typ);
7564 Resolve (Right_Opnd (N), B_Typ);
7565
7566 Check_Unset_Reference (Left_Opnd (N));
7567 Check_Unset_Reference (Right_Opnd (N));
7568
7569 Set_Etype (N, B_Typ);
fbf5a39b 7570 Generate_Operator_Reference (N, B_Typ);
996ae0b0 7571 Eval_Logical_Op (N);
9f90d123 7572
2ba431e5
YM		 7573 -- In SPARK, logical operations AND, OR and XOR for arrays are defined
7574 -- only when both operands have same static lower and higher bounds. Of
7575 -- course the types have to match, so only check if operands are
7576 -- compatible and the node itself has no errors.
9f90d123 7577
f5afb270
AC		 7578 if Is_Array_Type (B_Typ)
7579 and then Nkind (N) in N_Binary_Op
7580 then
7581 declare
7582 Left_Typ : constant Node_Id := Etype (Left_Opnd (N));
7583 Right_Typ : constant Node_Id := Etype (Right_Opnd (N));
2598ee6d 7584
f5afb270 7585 begin
7b98672f
YM		 7586 -- Protect call to Matching_Static_Array_Bounds to avoid costly
7587 -- operation if not needed.
7588
7589 if Restriction_Check_Required (SPARK)
7590 and then Base_Type (Left_Typ) = Base_Type (Right_Typ)
f5afb270
AC		 7591 and then Left_Typ /= Any_Composite -- or Left_Opnd in error
7592 and then Right_Typ /= Any_Composite -- or Right_Opnd in error
7593 and then not Matching_Static_Array_Bounds (Left_Typ, Right_Typ)
7594 then
2ba431e5 7595 Check_SPARK_Restriction
f5afb270
AC		 7596 ("array types should have matching static bounds", N);
7597 end if;
7598 end;
7599 end if;
996ae0b0
RK		 7600 end Resolve_Logical_Op;
7601
7602 ---------------------------
7603 -- Resolve_Membership_Op --
7604 ---------------------------
7605
5cc9353d
RD		 7606 -- The context can only be a boolean type, and does not determine the
7607 -- arguments. Arguments should be unambiguous, but the preference rule for
7608 -- universal types applies.
996ae0b0
RK		 7609
7610 procedure Resolve_Membership_Op (N : Node_Id; Typ : Entity_Id) is
07fc65c4
GB		 7611 pragma Warnings (Off, Typ);
7612
197e4514 7613 L : constant Node_Id := Left_Opnd (N);
b1c11e0e 7614 R : constant Node_Id := Right_Opnd (N);
996ae0b0
RK		 7615 T : Entity_Id;
7616
197e4514 7617 procedure Resolve_Set_Membership;
5cc9353d
RD		 7618 -- Analysis has determined a unique type for the left operand. Use it to
7619 -- resolve the disjuncts.
197e4514
AC		 7620
7621 ----------------------------
7622 -- Resolve_Set_Membership --
7623 ----------------------------
7624
7625 procedure Resolve_Set_Membership is
7626 Alt : Node_Id;
7627
7628 begin
7629 Resolve (L, Etype (L));
7630
7631 Alt := First (Alternatives (N));
7632 while Present (Alt) loop
7633
7634 -- Alternative is an expression, a range
7635 -- or a subtype mark.
7636
7637 if not Is_Entity_Name (Alt)
7638 or else not Is_Type (Entity (Alt))
7639 then
7640 Resolve (Alt, Etype (L));
7641 end if;
7642
7643 Next (Alt);
7644 end loop;
7645 end Resolve_Set_Membership;
7646
442c0581 7647 -- Start of processing for Resolve_Membership_Op
197e4514 7648
996ae0b0
RK		 7649 begin
7650 if L = Error or else R = Error then
7651 return;
7652 end if;
7653
197e4514
AC		 7654 if Present (Alternatives (N)) then
7655 Resolve_Set_Membership;
7656 return;
7657
7658 elsif not Is_Overloaded (R)
996ae0b0 7659 and then
19fb051c
AC		 7660 (Etype (R) = Universal_Integer
7661 or else
996ae0b0
RK		 7662 Etype (R) = Universal_Real)
7663 and then Is_Overloaded (L)
7664 then
7665 T := Etype (R);
1420b484 7666
d81b4bfe 7667 -- Ada 2005 (AI-251): Support the following case:
1420b484
JM		 7668
7669 -- type I is interface;
7670 -- type T is tagged ...
7671
c8ef728f 7672 -- function Test (O : I'Class) is
1420b484
JM		 7673 -- begin
7674 -- return O in T'Class.
7675 -- end Test;
7676
d81b4bfe 7677 -- In this case we have nothing else to do. The membership test will be
e7c0dd39 7678 -- done at run time.
1420b484 7679
0791fbe9 7680 elsif Ada_Version >= Ada_2005
1420b484
JM		 7681 and then Is_Class_Wide_Type (Etype (L))
7682 and then Is_Interface (Etype (L))
7683 and then Is_Class_Wide_Type (Etype (R))
7684 and then not Is_Interface (Etype (R))
7685 then
7686 return;
996ae0b0
RK		 7687 else
7688 T := Intersect_Types (L, R);
7689 end if;
7690
9a0ddeee
AC		 7691 -- If mixed-mode operations are present and operands are all literal,
7692 -- the only interpretation involves Duration, which is probably not
7693 -- the intention of the programmer.
7694
7695 if T = Any_Fixed then
7696 T := Unique_Fixed_Point_Type (N);
7697
7698 if T = Any_Type then
7699 return;
7700 end if;
7701 end if;
7702
996ae0b0
RK		 7703 Resolve (L, T);
7704 Check_Unset_Reference (L);
7705
7706 if Nkind (R) = N_Range
7707 and then not Is_Scalar_Type (T)
7708 then
7709 Error_Msg_N ("scalar type required for range", R);
7710 end if;
7711
7712 if Is_Entity_Name (R) then
7713 Freeze_Expression (R);
7714 else
7715 Resolve (R, T);
7716 Check_Unset_Reference (R);
7717 end if;
7718
7719 Eval_Membership_Op (N);
7720 end Resolve_Membership_Op;
7721
7722 ------------------
7723 -- Resolve_Null --
7724 ------------------
7725
7726 procedure Resolve_Null (N : Node_Id; Typ : Entity_Id) is
b1c11e0e
JM		 7727 Loc : constant Source_Ptr := Sloc (N);
7728
996ae0b0 7729 begin
758c442c 7730 -- Handle restriction against anonymous null access values This
6ba6b1e3 7731 -- restriction can be turned off using -gnatdj.
996ae0b0 7732
0ab80019 7733 -- Ada 2005 (AI-231): Remove restriction
2820d220 7734
0791fbe9 7735 if Ada_Version < Ada_2005
2820d220 7736 and then not Debug_Flag_J
996ae0b0
RK		 7737 and then Ekind (Typ) = E_Anonymous_Access_Type
7738 and then Comes_From_Source (N)
7739 then
d81b4bfe
TQ		 7740 -- In the common case of a call which uses an explicitly null value
7741 -- for an access parameter, give specialized error message.
996ae0b0 7742
d3b00ce3 7743 if Nkind (Parent (N)) in N_Subprogram_Call then
996ae0b0
RK		 7744 Error_Msg_N
7745 ("null is not allowed as argument for an access parameter", N);
7746
7747 -- Standard message for all other cases (are there any?)
7748
7749 else
7750 Error_Msg_N
7751 ("null cannot be of an anonymous access type", N);
7752 end if;
7753 end if;
7754
b1c11e0e
JM		 7755 -- Ada 2005 (AI-231): Generate the null-excluding check in case of
7756 -- assignment to a null-excluding object
7757
0791fbe9 7758 if Ada_Version >= Ada_2005
b1c11e0e
JM		 7759 and then Can_Never_Be_Null (Typ)
7760 and then Nkind (Parent (N)) = N_Assignment_Statement
7761 then
7762 if not Inside_Init_Proc then
7763 Insert_Action
7764 (Compile_Time_Constraint_Error (N,
7765 "(Ada 2005) null not allowed in null-excluding objects?"),
7766 Make_Raise_Constraint_Error (Loc,
7767 Reason => CE_Access_Check_Failed));
7768 else
7769 Insert_Action (N,
7770 Make_Raise_Constraint_Error (Loc,
7771 Reason => CE_Access_Check_Failed));
7772 end if;
7773 end if;
7774
d81b4bfe
TQ		 7775 -- In a distributed context, null for a remote access to subprogram may
7776 -- need to be replaced with a special record aggregate. In this case,
7777 -- return after having done the transformation.
996ae0b0
RK		 7778
7779 if (Ekind (Typ) = E_Record_Type
7780 or else Is_Remote_Access_To_Subprogram_Type (Typ))
7781 and then Remote_AST_Null_Value (N, Typ)
7782 then
7783 return;
7784 end if;
7785
a77842bd 7786 -- The null literal takes its type from the context
996ae0b0
RK		 7787
7788 Set_Etype (N, Typ);
7789 end Resolve_Null;
7790
7791 -----------------------
7792 -- Resolve_Op_Concat --
7793 -----------------------
7794
7795 procedure Resolve_Op_Concat (N : Node_Id; Typ : Entity_Id) is
996ae0b0 7796
10303118
BD		 7797 -- We wish to avoid deep recursion, because concatenations are often
7798 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
7799 -- operands nonrecursively until we find something that is not a simple
7800 -- concatenation (A in this case). We resolve that, and then walk back
7801 -- up the tree following Parent pointers, calling Resolve_Op_Concat_Rest
7802 -- to do the rest of the work at each level. The Parent pointers allow
7803 -- us to avoid recursion, and thus avoid running out of memory. See also
d81b4bfe 7804 -- Sem_Ch4.Analyze_Concatenation, where a similar approach is used.
996ae0b0 7805
10303118
BD		 7806 NN : Node_Id := N;
7807 Op1 : Node_Id;
996ae0b0 7808
10303118
BD		 7809 begin
7810 -- The following code is equivalent to:
996ae0b0 7811
10303118
BD		 7812 -- Resolve_Op_Concat_First (NN, Typ);
7813 -- Resolve_Op_Concat_Arg (N, ...);
7814 -- Resolve_Op_Concat_Rest (N, Typ);
996ae0b0 7815
10303118
BD		 7816 -- where the Resolve_Op_Concat_Arg call recurses back here if the left
7817 -- operand is a concatenation.
996ae0b0 7818
10303118 7819 -- Walk down left operands
996ae0b0 7820
10303118
BD		 7821 loop
7822 Resolve_Op_Concat_First (NN, Typ);
7823 Op1 := Left_Opnd (NN);
7824 exit when not (Nkind (Op1) = N_Op_Concat
7825 and then not Is_Array_Type (Component_Type (Typ))
7826 and then Entity (Op1) = Entity (NN));
7827 NN := Op1;
7828 end loop;
996ae0b0 7829
10303118 7830 -- Now (given the above example) NN is A&B and Op1 is A
996ae0b0 7831
10303118 7832 -- First resolve Op1 ...
9ebe3743 7833
10303118 7834 Resolve_Op_Concat_Arg (NN, Op1, Typ, Is_Component_Left_Opnd (NN));
9ebe3743 7835
10303118
BD		 7836 -- ... then walk NN back up until we reach N (where we started), calling
7837 -- Resolve_Op_Concat_Rest along the way.
9ebe3743 7838
10303118
BD		 7839 loop
7840 Resolve_Op_Concat_Rest (NN, Typ);
7841 exit when NN = N;
7842 NN := Parent (NN);
7843 end loop;
2933b16c 7844
fe5d3068 7845 if Base_Type (Etype (N)) /= Standard_String then
2ba431e5 7846 Check_SPARK_Restriction
fe5d3068 7847 ("result of concatenation should have type String", N);
2933b16c 7848 end if;
10303118 7849 end Resolve_Op_Concat;
9ebe3743 7850
10303118
BD		 7851 ---------------------------
7852 -- Resolve_Op_Concat_Arg --
7853 ---------------------------
996ae0b0 7854
10303118
BD		 7855 procedure Resolve_Op_Concat_Arg
7856 (N : Node_Id;
7857 Arg : Node_Id;
7858 Typ : Entity_Id;
7859 Is_Comp : Boolean)
7860 is
7861 Btyp : constant Entity_Id := Base_Type (Typ);
668a19bc 7862 Ctyp : constant Entity_Id := Component_Type (Typ);
996ae0b0 7863
10303118
BD		 7864 begin
7865 if In_Instance then
7866 if Is_Comp
7867 or else (not Is_Overloaded (Arg)
7868 and then Etype (Arg) /= Any_Composite
668a19bc 7869 and then Covers (Ctyp, Etype (Arg)))
10303118 7870 then
668a19bc 7871 Resolve (Arg, Ctyp);
10303118
BD		 7872 else
7873 Resolve (Arg, Btyp);
7874 end if;
fbf5a39b 7875
668a19bc
ES		 7876 -- If both Array & Array and Array & Component are visible, there is a
7877 -- potential ambiguity that must be reported.
7878
7879 elsif Has_Compatible_Type (Arg, Ctyp) then
10303118 7880 if Nkind (Arg) = N_Aggregate
668a19bc 7881 and then Is_Composite_Type (Ctyp)
10303118 7882 then
668a19bc 7883 if Is_Private_Type (Ctyp) then
10303118 7884 Resolve (Arg, Btyp);
668a19bc
ES		 7885
7886 -- If the operation is user-defined and not overloaded use its
7887 -- profile. The operation may be a renaming, in which case it has
7888 -- been rewritten, and we want the original profile.
7889
7890 elsif not Is_Overloaded (N)
7891 and then Comes_From_Source (Entity (Original_Node (N)))
7892 and then Ekind (Entity (Original_Node (N))) = E_Function
7893 then
7894 Resolve (Arg,
7895 Etype
7896 (Next_Formal (First_Formal (Entity (Original_Node (N))))));
7897 return;
7898
7899 -- Otherwise an aggregate may match both the array type and the
7900 -- component type.
7901
10303118
BD		 7902 else
7903 Error_Msg_N ("ambiguous aggregate must be qualified", Arg);
7904 Set_Etype (Arg, Any_Type);
996ae0b0
RK		 7905 end if;
7906
7907 else
10303118
BD		 7908 if Is_Overloaded (Arg)
7909 and then Has_Compatible_Type (Arg, Typ)
7910 and then Etype (Arg) /= Any_Type
7911 then
7912 declare
7913 I : Interp_Index;
7914 It : Interp;
7915 Func : Entity_Id;
7916
7917 begin
7918 Get_First_Interp (Arg, I, It);
7919 Func := It.Nam;
7920 Get_Next_Interp (I, It);
7921
7922 -- Special-case the error message when the overloading is
7923 -- caused by a function that yields an array and can be
7924 -- called without parameters.
7925
7926 if It.Nam = Func then
7927 Error_Msg_Sloc := Sloc (Func);
7928 Error_Msg_N ("ambiguous call to function#", Arg);
7929 Error_Msg_NE
7930 ("\\interpretation as call yields&", Arg, Typ);
7931 Error_Msg_NE
7932 ("\\interpretation as indexing of call yields&",
7933 Arg, Component_Type (Typ));
7934
7935 else
668a19bc 7936 Error_Msg_N ("ambiguous operand for concatenation!", Arg);
19fb051c 7937
10303118
BD		 7938 Get_First_Interp (Arg, I, It);
7939 while Present (It.Nam) loop
7940 Error_Msg_Sloc := Sloc (It.Nam);
7941
668a19bc
ES		 7942 if Base_Type (It.Typ) = Btyp
7943 or else
7944 Base_Type (It.Typ) = Base_Type (Ctyp)
10303118 7945 then
4e7a4f6e
AC		 7946 Error_Msg_N -- CODEFIX
7947 ("\\possible interpretation#", Arg);
10303118
BD		 7948 end if;
7949
7950 Get_Next_Interp (I, It);
7951 end loop;
7952 end if;
7953 end;
7954 end if;
7955
7956 Resolve (Arg, Component_Type (Typ));
7957
7958 if Nkind (Arg) = N_String_Literal then
7959 Set_Etype (Arg, Component_Type (Typ));
7960 end if;
7961
7962 if Arg = Left_Opnd (N) then
7963 Set_Is_Component_Left_Opnd (N);
7964 else
7965 Set_Is_Component_Right_Opnd (N);
7966 end if;
996ae0b0
RK		 7967 end if;
7968
10303118
BD		 7969 else
7970 Resolve (Arg, Btyp);
7971 end if;
7972
2ba431e5 7973 -- Concatenation is restricted in SPARK: each operand must be either a
92e77027
AC		 7974 -- string literal, the name of a string constant, a static character or
7975 -- string expression, or another concatenation. Arg cannot be a
7976 -- concatenation here as callers of Resolve_Op_Concat_Arg call it
7977 -- separately on each final operand, past concatenation operations.
2933b16c 7978
fe5d3068
YM		 7979 if Is_Character_Type (Etype (Arg)) then
7980 if not Is_Static_Expression (Arg) then
2ba431e5 7981 Check_SPARK_Restriction
5b5588dd 7982 ("character operand for concatenation should be static", Arg);
fe5d3068 7983 end if;
2933b16c 7984
fe5d3068 7985 elsif Is_String_Type (Etype (Arg)) then
92e77027
AC		 7986 if not (Nkind_In (Arg, N_Identifier, N_Expanded_Name)
7987 and then Is_Constant_Object (Entity (Arg)))
7988 and then not Is_Static_Expression (Arg)
7989 then
2ba431e5 7990 Check_SPARK_Restriction
5b5588dd 7991 ("string operand for concatenation should be static", Arg);
fe5d3068 7992 end if;
2933b16c 7993
b9e48541
AC		 7994 -- Do not issue error on an operand that is neither a character nor a
7995 -- string, as the error is issued in Resolve_Op_Concat.
2933b16c 7996
fe5d3068
YM		 7997 else
7998 null;
2933b16c
RD		 7999 end if;
8000
10303118
BD		 8001 Check_Unset_Reference (Arg);
8002 end Resolve_Op_Concat_Arg;
996ae0b0 8003
10303118
BD		 8004 -----------------------------
8005 -- Resolve_Op_Concat_First --
8006 -----------------------------
8007
8008 procedure Resolve_Op_Concat_First (N : Node_Id; Typ : Entity_Id) is
8009 Btyp : constant Entity_Id := Base_Type (Typ);
8010 Op1 : constant Node_Id := Left_Opnd (N);
8011 Op2 : constant Node_Id := Right_Opnd (N);
996ae0b0
RK		 8012
8013 begin
dae2b8ea
HK		 8014 -- The parser folds an enormous sequence of concatenations of string
8015 -- literals into "" & "...", where the Is_Folded_In_Parser flag is set
4fc26524 8016 -- in the right operand. If the expression resolves to a predefined "&"
dae2b8ea
HK		 8017 -- operator, all is well. Otherwise, the parser's folding is wrong, so
8018 -- we give an error. See P_Simple_Expression in Par.Ch4.
8019
8020 if Nkind (Op2) = N_String_Literal
8021 and then Is_Folded_In_Parser (Op2)
8022 and then Ekind (Entity (N)) = E_Function
8023 then
8024 pragma Assert (Nkind (Op1) = N_String_Literal -- should be ""
8025 and then String_Length (Strval (Op1)) = 0);
8026 Error_Msg_N ("too many user-defined concatenations", N);
8027 return;
8028 end if;
8029
996ae0b0
RK		 8030 Set_Etype (N, Btyp);
8031
8032 if Is_Limited_Composite (Btyp) then
8033 Error_Msg_N ("concatenation not available for limited array", N);
fbf5a39b 8034 Explain_Limited_Type (Btyp, N);
996ae0b0 8035 end if;
10303118 8036 end Resolve_Op_Concat_First;
996ae0b0 8037
10303118
BD		 8038 ----------------------------
8039 -- Resolve_Op_Concat_Rest --
8040 ----------------------------
996ae0b0 8041
10303118
BD		 8042 procedure Resolve_Op_Concat_Rest (N : Node_Id; Typ : Entity_Id) is
8043 Op1 : constant Node_Id := Left_Opnd (N);
8044 Op2 : constant Node_Id := Right_Opnd (N);
996ae0b0 8045
10303118
BD		 8046 begin
8047 Resolve_Op_Concat_Arg (N, Op2, Typ, Is_Component_Right_Opnd (N));
996ae0b0 8048
fbf5a39b 8049 Generate_Operator_Reference (N, Typ);
996ae0b0
RK		 8050
8051 if Is_String_Type (Typ) then
8052 Eval_Concatenation (N);
8053 end if;
8054
d81b4bfe
TQ		 8055 -- If this is not a static concatenation, but the result is a string
8056 -- type (and not an array of strings) ensure that static string operands
8057 -- have their subtypes properly constructed.
996ae0b0
RK		 8058
8059 if Nkind (N) /= N_String_Literal
8060 and then Is_Character_Type (Component_Type (Typ))
8061 then
8062 Set_String_Literal_Subtype (Op1, Typ);
8063 Set_String_Literal_Subtype (Op2, Typ);
8064 end if;
10303118 8065 end Resolve_Op_Concat_Rest;
996ae0b0
RK		 8066
8067 ----------------------
8068 -- Resolve_Op_Expon --
8069 ----------------------
8070
8071 procedure Resolve_Op_Expon (N : Node_Id; Typ : Entity_Id) is
8072 B_Typ : constant Entity_Id := Base_Type (Typ);
8073
8074 begin
f3d57416 8075 -- Catch attempts to do fixed-point exponentiation with universal
758c442c
GD		 8076 -- operands, which is a case where the illegality is not caught during
8077 -- normal operator analysis.
996ae0b0
RK		 8078
8079 if Is_Fixed_Point_Type (Typ) and then Comes_From_Source (N) then
8080 Error_Msg_N ("exponentiation not available for fixed point", N);
4d792549
AC		 8081 return;
8082
8083 elsif Nkind (Parent (N)) in N_Op
8084 and then Is_Fixed_Point_Type (Etype (Parent (N)))
8085 and then Etype (N) = Universal_Real
8086 and then Comes_From_Source (N)
8087 then
8088 Error_Msg_N ("exponentiation not available for fixed point", N);
996ae0b0
RK		 8089 return;
8090 end if;
8091
fbf5a39b
AC		 8092 if Comes_From_Source (N)
8093 and then Ekind (Entity (N)) = E_Function
8094 and then Is_Imported (Entity (N))
8095 and then Is_Intrinsic_Subprogram (Entity (N))
8096 then
8097 Resolve_Intrinsic_Operator (N, Typ);
8098 return;
8099 end if;
8100
996ae0b0
RK		 8101 if Etype (Left_Opnd (N)) = Universal_Integer
8102 or else Etype (Left_Opnd (N)) = Universal_Real
8103 then
8104 Check_For_Visible_Operator (N, B_Typ);
8105 end if;
8106
8107 -- We do the resolution using the base type, because intermediate values
8108 -- in expressions always are of the base type, not a subtype of it.
8109
8110 Resolve (Left_Opnd (N), B_Typ);
8111 Resolve (Right_Opnd (N), Standard_Integer);
8112
8113 Check_Unset_Reference (Left_Opnd (N));
8114 Check_Unset_Reference (Right_Opnd (N));
8115
8116 Set_Etype (N, B_Typ);
fbf5a39b 8117 Generate_Operator_Reference (N, B_Typ);
dec6faf1
AC		 8118
8119 Analyze_Dimension (N);
8120
15954beb 8121 if Ada_Version >= Ada_2012 and then Has_Dimension_System (B_Typ) then
6c57023b 8122 -- Evaluate the exponentiation operator for dimensioned type
dec6faf1 8123
6c57023b
AC		 8124 Eval_Op_Expon_For_Dimensioned_Type (N, B_Typ);
8125 else
8126 Eval_Op_Expon (N);
dec6faf1
AC		 8127 end if;
8128
996ae0b0
RK		 8129 -- Set overflow checking bit. Much cleverer code needed here eventually
8130 -- and perhaps the Resolve routines should be separated for the various
8131 -- arithmetic operations, since they will need different processing. ???
8132
8133 if Nkind (N) in N_Op then
8134 if not Overflow_Checks_Suppressed (Etype (N)) then
fbf5a39b 8135 Enable_Overflow_Check (N);
996ae0b0
RK		 8136 end if;
8137 end if;
996ae0b0
RK		 8138 end Resolve_Op_Expon;
8139
8140 --------------------
8141 -- Resolve_Op_Not --
8142 --------------------
8143
8144 procedure Resolve_Op_Not (N : Node_Id; Typ : Entity_Id) is
8145 B_Typ : Entity_Id;
8146
8147 function Parent_Is_Boolean return Boolean;
5cc9353d
RD		 8148 -- This function determines if the parent node is a boolean operator or
8149 -- operation (comparison op, membership test, or short circuit form) and
8150 -- the not in question is the left operand of this operation. Note that
8151 -- if the not is in parens, then false is returned.
996ae0b0 8152
aa180613
RD		 8153 -----------------------
8154 -- Parent_Is_Boolean --
8155 -----------------------
8156
996ae0b0
RK		 8157 function Parent_Is_Boolean return Boolean is
8158 begin
8159 if Paren_Count (N) /= 0 then
8160 return False;
8161
8162 else
8163 case Nkind (Parent (N)) is
8164 when N_Op_And |
8165 N_Op_Eq |
8166 N_Op_Ge |
8167 N_Op_Gt |
8168 N_Op_Le |
8169 N_Op_Lt |
8170 N_Op_Ne |
8171 N_Op_Or |
8172 N_Op_Xor |
8173 N_In |
8174 N_Not_In |
8175 N_And_Then |
aa180613 8176 N_Or_Else =>
996ae0b0
RK		 8177
8178 return Left_Opnd (Parent (N)) = N;
8179
8180 when others =>
8181 return False;
8182 end case;
8183 end if;
8184 end Parent_Is_Boolean;
8185
8186 -- Start of processing for Resolve_Op_Not
8187
8188 begin
758c442c
GD		 8189 -- Predefined operations on scalar types yield the base type. On the
8190 -- other hand, logical operations on arrays yield the type of the
8191 -- arguments (and the context).
996ae0b0
RK		 8192
8193 if Is_Array_Type (Typ) then
8194 B_Typ := Typ;
8195 else
8196 B_Typ := Base_Type (Typ);
8197 end if;
8198
001c7783
AC		 8199 if Is_VMS_Operator (Entity (N)) then
8200 null;
8201
f3d57416 8202 -- Straightforward case of incorrect arguments
aa180613 8203
001c7783 8204 elsif not Valid_Boolean_Arg (Typ) then
996ae0b0
RK		 8205 Error_Msg_N ("invalid operand type for operator&", N);
8206 Set_Etype (N, Any_Type);
8207 return;
8208
aa180613
RD		 8209 -- Special case of probable missing parens
8210
fbf5a39b 8211 elsif Typ = Universal_Integer or else Typ = Any_Modular then
996ae0b0 8212 if Parent_Is_Boolean then
ed2233dc 8213 Error_Msg_N
996ae0b0
RK		 8214 ("operand of not must be enclosed in parentheses",
8215 Right_Opnd (N));
8216 else
8217 Error_Msg_N
8218 ("no modular type available in this context", N);
8219 end if;
8220
8221 Set_Etype (N, Any_Type);
8222 return;
8223
5cc9353d 8224 -- OK resolution of NOT
aa180613 8225
996ae0b0 8226 else
aa180613
RD		 8227 -- Warn if non-boolean types involved. This is a case like not a < b
8228 -- where a and b are modular, where we will get (not a) < b and most
8229 -- likely not (a < b) was intended.
8230
8231 if Warn_On_Questionable_Missing_Parens
8232 and then not Is_Boolean_Type (Typ)
996ae0b0
RK		 8233 and then Parent_Is_Boolean
8234 then
ed2233dc 8235 Error_Msg_N ("?not expression should be parenthesized here!", N);
996ae0b0
RK		 8236 end if;
8237
09bc9ab6
RD		 8238 -- Warn on double negation if checking redundant constructs
8239
8240 if Warn_On_Redundant_Constructs
8241 and then Comes_From_Source (N)
8242 and then Comes_From_Source (Right_Opnd (N))
8243 and then Root_Type (Typ) = Standard_Boolean
8244 and then Nkind (Right_Opnd (N)) = N_Op_Not
8245 then
ed2233dc 8246 Error_Msg_N ("redundant double negation?", N);
09bc9ab6
RD		 8247 end if;
8248
8249 -- Complete resolution and evaluation of NOT
8250
996ae0b0
RK		 8251 Resolve (Right_Opnd (N), B_Typ);
8252 Check_Unset_Reference (Right_Opnd (N));
8253 Set_Etype (N, B_Typ);
fbf5a39b 8254 Generate_Operator_Reference (N, B_Typ);
996ae0b0
RK		 8255 Eval_Op_Not (N);
8256 end if;
8257 end Resolve_Op_Not;
8258
8259 -----------------------------
8260 -- Resolve_Operator_Symbol --
8261 -----------------------------
8262
8263 -- Nothing to be done, all resolved already
8264
8265 procedure Resolve_Operator_Symbol (N : Node_Id; Typ : Entity_Id) is
07fc65c4
GB		 8266 pragma Warnings (Off, N);
8267 pragma Warnings (Off, Typ);
8268
996ae0b0
RK		 8269 begin
8270 null;
8271 end Resolve_Operator_Symbol;
8272
8273 ----------------------------------
8274 -- Resolve_Qualified_Expression --
8275 ----------------------------------
8276
8277 procedure Resolve_Qualified_Expression (N : Node_Id; Typ : Entity_Id) is
07fc65c4
GB		 8278 pragma Warnings (Off, Typ);
8279
996ae0b0
RK		 8280 Target_Typ : constant Entity_Id := Entity (Subtype_Mark (N));
8281 Expr : constant Node_Id := Expression (N);
8282
8283 begin
8284 Resolve (Expr, Target_Typ);
8285
7b98672f
YM		 8286 -- Protect call to Matching_Static_Array_Bounds to avoid costly
8287 -- operation if not needed.
8288
8289 if Restriction_Check_Required (SPARK)
8290 and then Is_Array_Type (Target_Typ)
b0186f71 8291 and then Is_Array_Type (Etype (Expr))
db72f10a 8292 and then Etype (Expr) /= Any_Composite -- or else Expr in error
b0186f71
AC		 8293 and then not Matching_Static_Array_Bounds (Target_Typ, Etype (Expr))
8294 then
2ba431e5 8295 Check_SPARK_Restriction
fe5d3068 8296 ("array types should have matching static bounds", N);
b0186f71
AC		 8297 end if;
8298
5cc9353d
RD		 8299 -- A qualified expression requires an exact match of the type, class-
8300 -- wide matching is not allowed. However, if the qualifying type is
8301 -- specific and the expression has a class-wide type, it may still be
8302 -- okay, since it can be the result of the expansion of a call to a
8303 -- dispatching function, so we also have to check class-wideness of the
8304 -- type of the expression's original node.
1420b484
JM		 8305
8306 if (Is_Class_Wide_Type (Target_Typ)
8307 or else
8308 (Is_Class_Wide_Type (Etype (Expr))
8309 and then Is_Class_Wide_Type (Etype (Original_Node (Expr)))))
996ae0b0
RK		 8310 and then Base_Type (Etype (Expr)) /= Base_Type (Target_Typ)
8311 then
8312 Wrong_Type (Expr, Target_Typ);
8313 end if;
8314
90c63b09
AC		 8315 -- If the target type is unconstrained, then we reset the type of the
8316 -- result from the type of the expression. For other cases, the actual
8317 -- subtype of the expression is the target type.
996ae0b0
RK		 8318
8319 if Is_Composite_Type (Target_Typ)
8320 and then not Is_Constrained (Target_Typ)
8321 then
8322 Set_Etype (N, Etype (Expr));
8323 end if;
8324
dec6faf1 8325 Analyze_Dimension (N);
996ae0b0
RK		 8326 Eval_Qualified_Expression (N);
8327 end Resolve_Qualified_Expression;
8328
8329 -------------------
8330 -- Resolve_Range --
8331 -------------------
8332
8333 procedure Resolve_Range (N : Node_Id; Typ : Entity_Id) is
8334 L : constant Node_Id := Low_Bound (N);
8335 H : constant Node_Id := High_Bound (N);
8336
bd29d519
AC		 8337 function First_Last_Ref return Boolean;
8338 -- Returns True if N is of the form X'First .. X'Last where X is the
8339 -- same entity for both attributes.
8340
8341 --------------------
8342 -- First_Last_Ref --
8343 --------------------
8344
8345 function First_Last_Ref return Boolean is
8346 Lorig : constant Node_Id := Original_Node (L);
8347 Horig : constant Node_Id := Original_Node (H);
8348
8349 begin
8350 if Nkind (Lorig) = N_Attribute_Reference
8351 and then Nkind (Horig) = N_Attribute_Reference
8352 and then Attribute_Name (Lorig) = Name_First
8353 and then Attribute_Name (Horig) = Name_Last
8354 then
8355 declare
8356 PL : constant Node_Id := Prefix (Lorig);
8357 PH : constant Node_Id := Prefix (Horig);
8358 begin
8359 if Is_Entity_Name (PL)
8360 and then Is_Entity_Name (PH)
8361 and then Entity (PL) = Entity (PH)
8362 then
8363 return True;
8364 end if;
8365 end;
8366 end if;
8367
8368 return False;
8369 end First_Last_Ref;
8370
8371 -- Start of processing for Resolve_Range
8372
996ae0b0
RK		 8373 begin
8374 Set_Etype (N, Typ);
8375 Resolve (L, Typ);
8376 Resolve (H, Typ);
8377
bd29d519
AC		 8378 -- Check for inappropriate range on unordered enumeration type
8379
8380 if Bad_Unordered_Enumeration_Reference (N, Typ)
8381
8382 -- Exclude X'First .. X'Last if X is the same entity for both
8383
8384 and then not First_Last_Ref
8385 then
8386 Error_Msg ("subrange of unordered enumeration type?", Sloc (N));
498d1b80
AC		 8387 end if;
8388
996ae0b0
RK		 8389 Check_Unset_Reference (L);
8390 Check_Unset_Reference (H);
8391
8392 -- We have to check the bounds for being within the base range as
758c442c
GD		 8393 -- required for a non-static context. Normally this is automatic and
8394 -- done as part of evaluating expressions, but the N_Range node is an
8395 -- exception, since in GNAT we consider this node to be a subexpression,
8396 -- even though in Ada it is not. The circuit in Sem_Eval could check for
8397 -- this, but that would put the test on the main evaluation path for
8398 -- expressions.
996ae0b0
RK		 8399
8400 Check_Non_Static_Context (L);
8401 Check_Non_Static_Context (H);
8402
b7d1f17f
HK		 8403 -- Check for an ambiguous range over character literals. This will
8404 -- happen with a membership test involving only literals.
8405
8406 if Typ = Any_Character then
8407 Ambiguous_Character (L);
8408 Set_Etype (N, Any_Type);
8409 return;
8410 end if;
8411
5cc9353d
RD		 8412 -- If bounds are static, constant-fold them, so size computations are
8413 -- identical between front-end and back-end. Do not perform this
fbf5a39b 8414 -- transformation while analyzing generic units, as type information
5cc9353d 8415 -- would be lost when reanalyzing the constant node in the instance.
fbf5a39b 8416
11fa950b 8417 if Is_Discrete_Type (Typ) and then Full_Expander_Active then
fbf5a39b
AC		 8418 if Is_OK_Static_Expression (L) then
8419 Fold_Uint (L, Expr_Value (L), Is_Static_Expression (L));
8420 end if;
8421
8422 if Is_OK_Static_Expression (H) then
8423 Fold_Uint (H, Expr_Value (H), Is_Static_Expression (H));
8424 end if;
8425 end if;
996ae0b0
RK		 8426 end Resolve_Range;
8427
8428 --------------------------
8429 -- Resolve_Real_Literal --
8430 --------------------------
8431
8432 procedure Resolve_Real_Literal (N : Node_Id; Typ : Entity_Id) is
8433 Actual_Typ : constant Entity_Id := Etype (N);
8434
8435 begin
8436 -- Special processing for fixed-point literals to make sure that the
5cc9353d
RD		 8437 -- value is an exact multiple of small where this is required. We skip
8438 -- this for the universal real case, and also for generic types.
996ae0b0
RK		 8439
8440 if Is_Fixed_Point_Type (Typ)
8441 and then Typ /= Universal_Fixed
8442 and then Typ /= Any_Fixed
8443 and then not Is_Generic_Type (Typ)
8444 then
8445 declare
8446 Val : constant Ureal := Realval (N);
8447 Cintr : constant Ureal := Val / Small_Value (Typ);
8448 Cint : constant Uint := UR_Trunc (Cintr);
8449 Den : constant Uint := Norm_Den (Cintr);
8450 Stat : Boolean;
8451
8452 begin
8453 -- Case of literal is not an exact multiple of the Small
8454
8455 if Den /= 1 then
8456
5cc9353d
RD		 8457 -- For a source program literal for a decimal fixed-point type,
8458 -- this is statically illegal (RM 4.9(36)).
996ae0b0
RK		 8459
8460 if Is_Decimal_Fixed_Point_Type (Typ)
8461 and then Actual_Typ = Universal_Real
8462 and then Comes_From_Source (N)
8463 then
8464 Error_Msg_N ("value has extraneous low order digits", N);
8465 end if;
8466
bc5f3720
RD		 8467 -- Generate a warning if literal from source
8468
8469 if Is_Static_Expression (N)
8470 and then Warn_On_Bad_Fixed_Value
8471 then
8472 Error_Msg_N
aa5147f0 8473 ("?static fixed-point value is not a multiple of Small!",
bc5f3720
RD		 8474 N);
8475 end if;
8476
996ae0b0
RK		 8477 -- Replace literal by a value that is the exact representation
8478 -- of a value of the type, i.e. a multiple of the small value,
8479 -- by truncation, since Machine_Rounds is false for all GNAT
8480 -- fixed-point types (RM 4.9(38)).
8481
8482 Stat := Is_Static_Expression (N);
8483 Rewrite (N,
8484 Make_Real_Literal (Sloc (N),
8485 Realval => Small_Value (Typ) * Cint));
8486
8487 Set_Is_Static_Expression (N, Stat);
8488 end if;
8489
8490 -- In all cases, set the corresponding integer field
8491
8492 Set_Corresponding_Integer_Value (N, Cint);
8493 end;
8494 end if;
8495
8496 -- Now replace the actual type by the expected type as usual
8497
8498 Set_Etype (N, Typ);
8499 Eval_Real_Literal (N);
8500 end Resolve_Real_Literal;
8501
8502 -----------------------
8503 -- Resolve_Reference --
8504 -----------------------
8505
8506 procedure Resolve_Reference (N : Node_Id; Typ : Entity_Id) is
8507 P : constant Node_Id := Prefix (N);
8508
8509 begin
8510 -- Replace general access with specific type
8511
8512 if Ekind (Etype (N)) = E_Allocator_Type then
8513 Set_Etype (N, Base_Type (Typ));
8514 end if;
8515
8516 Resolve (P, Designated_Type (Etype (N)));
8517
5cc9353d
RD		 8518 -- If we are taking the reference of a volatile entity, then treat it as
8519 -- a potential modification of this entity. This is too conservative,
8520 -- but necessary because remove side effects can cause transformations
8521 -- of normal assignments into reference sequences that otherwise fail to
8522 -- notice the modification.
996ae0b0 8523
fbf5a39b 8524 if Is_Entity_Name (P) and then Treat_As_Volatile (Entity (P)) then
45fc7ddb 8525 Note_Possible_Modification (P, Sure => False);
996ae0b0
RK		 8526 end if;
8527 end Resolve_Reference;
8528
8529 --------------------------------
8530 -- Resolve_Selected_Component --
8531 --------------------------------
8532
8533 procedure Resolve_Selected_Component (N : Node_Id; Typ : Entity_Id) is
8534 Comp : Entity_Id;
8535 Comp1 : Entity_Id := Empty; -- prevent junk warning
8536 P : constant Node_Id := Prefix (N);
8537 S : constant Node_Id := Selector_Name (N);
8538 T : Entity_Id := Etype (P);
8539 I : Interp_Index;
8540 I1 : Interp_Index := 0; -- prevent junk warning
8541 It : Interp;
8542 It1 : Interp;
8543 Found : Boolean;
8544
6510f4c9
GB		 8545 function Init_Component return Boolean;
8546 -- Check whether this is the initialization of a component within an
fbf5a39b 8547 -- init proc (by assignment or call to another init proc). If true,
6510f4c9
GB		 8548 -- there is no need for a discriminant check.
8549
8550 --------------------
8551 -- Init_Component --
8552 --------------------
8553
8554 function Init_Component return Boolean is
8555 begin
8556 return Inside_Init_Proc
8557 and then Nkind (Prefix (N)) = N_Identifier
8558 and then Chars (Prefix (N)) = Name_uInit
8559 and then Nkind (Parent (Parent (N))) = N_Case_Statement_Alternative;
8560 end Init_Component;
8561
8562 -- Start of processing for Resolve_Selected_Component
8563
996ae0b0
RK		 8564 begin
8565 if Is_Overloaded (P) then
8566
8567 -- Use the context type to select the prefix that has a selector
8568 -- of the correct name and type.
8569
8570 Found := False;
8571 Get_First_Interp (P, I, It);
8572
8573 Search : while Present (It.Typ) loop
8574 if Is_Access_Type (It.Typ) then
8575 T := Designated_Type (It.Typ);
8576 else
8577 T := It.Typ;
8578 end if;
8579
95eb8b69
AC		 8580 -- Locate selected component. For a private prefix the selector
8581 -- can denote a discriminant.
8582
8583 if Is_Record_Type (T) or else Is_Private_Type (T) then
36fcf362
RD		 8584
8585 -- The visible components of a class-wide type are those of
8586 -- the root type.
8587
8588 if Is_Class_Wide_Type (T) then
8589 T := Etype (T);
8590 end if;
8591
996ae0b0 8592 Comp := First_Entity (T);
996ae0b0 8593 while Present (Comp) loop
996ae0b0
RK		 8594 if Chars (Comp) = Chars (S)
8595 and then Covers (Etype (Comp), Typ)
8596 then
8597 if not Found then
8598 Found := True;
8599 I1 := I;
8600 It1 := It;
8601 Comp1 := Comp;
8602
8603 else
8604 It := Disambiguate (P, I1, I, Any_Type);
8605
8606 if It = No_Interp then
8607 Error_Msg_N
8608 ("ambiguous prefix for selected component", N);
8609 Set_Etype (N, Typ);
8610 return;
8611
8612 else
8613 It1 := It;
8614
c8ef728f
ES		 8615 -- There may be an implicit dereference. Retrieve
8616 -- designated record type.
8617
8618 if Is_Access_Type (It1.Typ) then
8619 T := Designated_Type (It1.Typ);
8620 else
8621 T := It1.Typ;
8622 end if;
8623
8624 if Scope (Comp1) /= T then
996ae0b0
RK		 8625
8626 -- Resolution chooses the new interpretation.
8627 -- Find the component with the right name.
8628
c8ef728f 8629 Comp1 := First_Entity (T);
996ae0b0
RK		 8630 while Present (Comp1)
8631 and then Chars (Comp1) /= Chars (S)
8632 loop
8633 Comp1 := Next_Entity (Comp1);
8634 end loop;
8635 end if;
8636
8637 exit Search;
8638 end if;
8639 end if;
8640 end if;
8641
8642 Comp := Next_Entity (Comp);
8643 end loop;
996ae0b0
RK		 8644 end if;
8645
8646 Get_Next_Interp (I, It);
996ae0b0
RK		 8647 end loop Search;
8648
8649 Resolve (P, It1.Typ);
8650 Set_Etype (N, Typ);
aa180613 8651 Set_Entity_With_Style_Check (S, Comp1);
996ae0b0
RK		 8652
8653 else
fbf5a39b 8654 -- Resolve prefix with its type
996ae0b0
RK		 8655
8656 Resolve (P, T);
8657 end if;
8658
aa180613
RD		 8659 -- Generate cross-reference. We needed to wait until full overloading
8660 -- resolution was complete to do this, since otherwise we can't tell if
01e17342 8661 -- we are an lvalue or not.
aa180613
RD		 8662
8663 if May_Be_Lvalue (N) then
8664 Generate_Reference (Entity (S), S, 'm');
8665 else
8666 Generate_Reference (Entity (S), S, 'r');
8667 end if;
8668
c8ef728f
ES		 8669 -- If prefix is an access type, the node will be transformed into an
8670 -- explicit dereference during expansion. The type of the node is the
8671 -- designated type of that of the prefix.
996ae0b0
RK		 8672
8673 if Is_Access_Type (Etype (P)) then
996ae0b0 8674 T := Designated_Type (Etype (P));
c8ef728f 8675 Check_Fully_Declared_Prefix (T, P);
996ae0b0
RK		 8676 else
8677 T := Etype (P);
8678 end if;
8679
8680 if Has_Discriminants (T)
964f13da 8681 and then Ekind_In (Entity (S), E_Component, E_Discriminant)
996ae0b0
RK		 8682 and then Present (Original_Record_Component (Entity (S)))
8683 and then Ekind (Original_Record_Component (Entity (S))) = E_Component
8684 and then Present (Discriminant_Checking_Func
8685 (Original_Record_Component (Entity (S))))
8686 and then not Discriminant_Checks_Suppressed (T)
6510f4c9 8687 and then not Init_Component
996ae0b0
RK		 8688 then
8689 Set_Do_Discriminant_Check (N);
8690 end if;
8691
8692 if Ekind (Entity (S)) = E_Void then
8693 Error_Msg_N ("premature use of component", S);
8694 end if;
8695
8696 -- If the prefix is a record conversion, this may be a renamed
8697 -- discriminant whose bounds differ from those of the original
8698 -- one, so we must ensure that a range check is performed.
8699
8700 if Nkind (P) = N_Type_Conversion
8701 and then Ekind (Entity (S)) = E_Discriminant
fbf5a39b 8702 and then Is_Discrete_Type (Typ)
996ae0b0
RK		 8703 then
8704 Set_Etype (N, Base_Type (Typ));
8705 end if;
8706
8707 -- Note: No Eval processing is required, because the prefix is of a
8708 -- record type, or protected type, and neither can possibly be static.
8709
c28408b7
RD		 8710 -- If the array type is atomic, and is packed, and we are in a left side
8711 -- context, then this is worth a warning, since we have a situation
5cc9353d
RD		 8712 -- where the access to the component may cause extra read/writes of the
8713 -- atomic array object, which could be considered unexpected.
c28408b7
RD		 8714
8715 if Nkind (N) = N_Selected_Component
8716 and then (Is_Atomic (T)
8717 or else (Is_Entity_Name (Prefix (N))
8718 and then Is_Atomic (Entity (Prefix (N)))))
8719 and then Is_Packed (T)
8720 and then Is_LHS (N)
8721 then
54c04d6c
AC		 8722 Error_Msg_N
8723 ("?assignment to component of packed atomic record", Prefix (N));
8724 Error_Msg_N
8725 ("?\may cause unexpected accesses to atomic object", Prefix (N));
c28408b7 8726 end if;
54c04d6c 8727
dec6faf1 8728 Analyze_Dimension (N);
996ae0b0
RK		 8729 end Resolve_Selected_Component;
8730
8731 -------------------
8732 -- Resolve_Shift --
8733 -------------------
8734
8735 procedure Resolve_Shift (N : Node_Id; Typ : Entity_Id) is
8736 B_Typ : constant Entity_Id := Base_Type (Typ);
8737 L : constant Node_Id := Left_Opnd (N);
8738 R : constant Node_Id := Right_Opnd (N);
8739
8740 begin
8741 -- We do the resolution using the base type, because intermediate values
8742 -- in expressions always are of the base type, not a subtype of it.
8743
8744 Resolve (L, B_Typ);
8745 Resolve (R, Standard_Natural);
8746
8747 Check_Unset_Reference (L);
8748 Check_Unset_Reference (R);
8749
8750 Set_Etype (N, B_Typ);
fbf5a39b 8751 Generate_Operator_Reference (N, B_Typ);
996ae0b0
RK		 8752 Eval_Shift (N);
8753 end Resolve_Shift;
8754
8755 ---------------------------
8756 -- Resolve_Short_Circuit --
8757 ---------------------------
8758
8759 procedure Resolve_Short_Circuit (N : Node_Id; Typ : Entity_Id) is
8760 B_Typ : constant Entity_Id := Base_Type (Typ);
8761 L : constant Node_Id := Left_Opnd (N);
8762 R : constant Node_Id := Right_Opnd (N);
8763
8764 begin
8765 Resolve (L, B_Typ);
8766 Resolve (R, B_Typ);
8767
45fc7ddb
HK		 8768 -- Check for issuing warning for always False assert/check, this happens
8769 -- when assertions are turned off, in which case the pragma Assert/Check
36fcf362
RD		 8770 -- was transformed into:
8771
8772 -- if False and then <condition> then ...
8773
8774 -- and we detect this pattern
8775
8776 if Warn_On_Assertion_Failure
8777 and then Is_Entity_Name (R)
8778 and then Entity (R) = Standard_False
8779 and then Nkind (Parent (N)) = N_If_Statement
8780 and then Nkind (N) = N_And_Then
8781 and then Is_Entity_Name (L)
8782 and then Entity (L) = Standard_False
8783 then
8784 declare
8785 Orig : constant Node_Id := Original_Node (Parent (N));
45fc7ddb 8786
36fcf362
RD		 8787 begin
8788 if Nkind (Orig) = N_Pragma
26570b21 8789 and then Pragma_Name (Orig) = Name_Assert
36fcf362
RD		 8790 then
8791 -- Don't want to warn if original condition is explicit False
8792
8793 declare
8794 Expr : constant Node_Id :=
8795 Original_Node
8796 (Expression
8797 (First (Pragma_Argument_Associations (Orig))));
8798 begin
8799 if Is_Entity_Name (Expr)
8800 and then Entity (Expr) = Standard_False
8801 then
8802 null;
8803 else
51bf9bdf
AC		 8804 -- Issue warning. We do not want the deletion of the
8805 -- IF/AND-THEN to take this message with it. We achieve
8806 -- this by making sure that the expanded code points to
8807 -- the Sloc of the expression, not the original pragma.
8808
8a06151a
RD		 8809 -- Note: Use Error_Msg_F here rather than Error_Msg_N.
8810 -- The source location of the expression is not usually
8811 -- the best choice here. For example, it gets located on
8812 -- the last AND keyword in a chain of boolean expressiond
8813 -- AND'ed together. It is best to put the message on the
8814 -- first character of the assertion, which is the effect
8815 -- of the First_Node call here.
8816
ca20a08e 8817 Error_Msg_F
e7c0dd39 8818 ("?assertion would fail at run time!",
51bf9bdf
AC		 8819 Expression
8820 (First (Pragma_Argument_Associations (Orig))));
36fcf362
RD		 8821 end if;
8822 end;
45fc7ddb
HK		 8823
8824 -- Similar processing for Check pragma
8825
8826 elsif Nkind (Orig) = N_Pragma
8827 and then Pragma_Name (Orig) = Name_Check
8828 then
8829 -- Don't want to warn if original condition is explicit False
8830
8831 declare
8832 Expr : constant Node_Id :=
8833 Original_Node
8834 (Expression
8835 (Next (First
8836 (Pragma_Argument_Associations (Orig)))));
8837 begin
8838 if Is_Entity_Name (Expr)
8839 and then Entity (Expr) = Standard_False
8840 then
8841 null;
8a06151a
RD		 8842
8843 -- Post warning
8844
45fc7ddb 8845 else
8a06151a
RD		 8846 -- Again use Error_Msg_F rather than Error_Msg_N, see
8847 -- comment above for an explanation of why we do this.
8848
ca20a08e 8849 Error_Msg_F
e7c0dd39 8850 ("?check would fail at run time!",
51bf9bdf
AC		 8851 Expression
8852 (Last (Pragma_Argument_Associations (Orig))));
45fc7ddb
HK		 8853 end if;
8854 end;
36fcf362
RD		 8855 end if;
8856 end;
8857 end if;
8858
8859 -- Continue with processing of short circuit
8860
996ae0b0
RK		 8861 Check_Unset_Reference (L);
8862 Check_Unset_Reference (R);
8863
8864 Set_Etype (N, B_Typ);
8865 Eval_Short_Circuit (N);
8866 end Resolve_Short_Circuit;
8867
8868 -------------------
8869 -- Resolve_Slice --
8870 -------------------
8871
8872 procedure Resolve_Slice (N : Node_Id; Typ : Entity_Id) is
996ae0b0 8873 Drange : constant Node_Id := Discrete_Range (N);
5f44f0d4 8874 Name : constant Node_Id := Prefix (N);
996ae0b0 8875 Array_Type : Entity_Id := Empty;
5f44f0d4 8876 Index_Type : Entity_Id;
996ae0b0
RK		 8877
8878 begin
8879 if Is_Overloaded (Name) then
8880
d81b4bfe
TQ		 8881 -- Use the context type to select the prefix that yields the correct
8882 -- array type.
996ae0b0
RK		 8883
8884 declare
8885 I : Interp_Index;
8886 I1 : Interp_Index := 0;
8887 It : Interp;
8888 P : constant Node_Id := Prefix (N);
8889 Found : Boolean := False;
8890
8891 begin
8892 Get_First_Interp (P, I, It);
996ae0b0 8893 while Present (It.Typ) loop
996ae0b0
RK		 8894 if (Is_Array_Type (It.Typ)
8895 and then Covers (Typ, It.Typ))
8896 or else (Is_Access_Type (It.Typ)
8897 and then Is_Array_Type (Designated_Type (It.Typ))
8898 and then Covers (Typ, Designated_Type (It.Typ)))
8899 then
8900 if Found then
8901 It := Disambiguate (P, I1, I, Any_Type);
8902
8903 if It = No_Interp then
8904 Error_Msg_N ("ambiguous prefix for slicing", N);
8905 Set_Etype (N, Typ);
8906 return;
8907 else
8908 Found := True;
8909 Array_Type := It.Typ;
8910 I1 := I;
8911 end if;
8912 else
8913 Found := True;
8914 Array_Type := It.Typ;
8915 I1 := I;
8916 end if;
8917 end if;
8918
8919 Get_Next_Interp (I, It);
8920 end loop;
8921 end;
8922
8923 else
8924 Array_Type := Etype (Name);
8925 end if;
8926
8927 Resolve (Name, Array_Type);
8928
8929 if Is_Access_Type (Array_Type) then
8930 Apply_Access_Check (N);
8931 Array_Type := Designated_Type (Array_Type);
8932
c8ef728f
ES		 8933 -- If the prefix is an access to an unconstrained array, we must use
8934 -- the actual subtype of the object to perform the index checks. The
8935 -- object denoted by the prefix is implicit in the node, so we build
8936 -- an explicit representation for it in order to compute the actual
8937 -- subtype.
82c80734
RD		 8938
8939 if not Is_Constrained (Array_Type) then
8940 Remove_Side_Effects (Prefix (N));
8941
8942 declare
8943 Obj : constant Node_Id :=
8944 Make_Explicit_Dereference (Sloc (N),
8945 Prefix => New_Copy_Tree (Prefix (N)));
8946 begin
8947 Set_Etype (Obj, Array_Type);
8948 Set_Parent (Obj, Parent (N));
8949 Array_Type := Get_Actual_Subtype (Obj);
8950 end;
8951 end if;
8952
996ae0b0 8953 elsif Is_Entity_Name (Name)
6c994759 8954 or else Nkind (Name) = N_Explicit_Dereference
996ae0b0
RK		 8955 or else (Nkind (Name) = N_Function_Call
8956 and then not Is_Constrained (Etype (Name)))
8957 then
8958 Array_Type := Get_Actual_Subtype (Name);
aa5147f0
ES		 8959
8960 -- If the name is a selected component that depends on discriminants,
8961 -- build an actual subtype for it. This can happen only when the name
8962 -- itself is overloaded; otherwise the actual subtype is created when
8963 -- the selected component is analyzed.
8964
8965 elsif Nkind (Name) = N_Selected_Component
8966 and then Full_Analysis
8967 and then Depends_On_Discriminant (First_Index (Array_Type))
8968 then
8969 declare
8970 Act_Decl : constant Node_Id :=
8971 Build_Actual_Subtype_Of_Component (Array_Type, Name);
8972 begin
8973 Insert_Action (N, Act_Decl);
8974 Array_Type := Defining_Identifier (Act_Decl);
8975 end;
d79e621a
GD		 8976
8977 -- Maybe this should just be "else", instead of checking for the
5cc9353d
RD		 8978 -- specific case of slice??? This is needed for the case where the
8979 -- prefix is an Image attribute, which gets expanded to a slice, and so
8980 -- has a constrained subtype which we want to use for the slice range
8981 -- check applied below (the range check won't get done if the
8982 -- unconstrained subtype of the 'Image is used).
d79e621a
GD		 8983
8984 elsif Nkind (Name) = N_Slice then
8985 Array_Type := Etype (Name);
996ae0b0
RK		 8986 end if;
8987
8988 -- If name was overloaded, set slice type correctly now
8989
8990 Set_Etype (N, Array_Type);
8991
c8ef728f
ES		 8992 -- If the range is specified by a subtype mark, no resolution is
8993 -- necessary. Else resolve the bounds, and apply needed checks.
996ae0b0
RK		 8994
8995 if not Is_Entity_Name (Drange) then
5f44f0d4
AC		 8996 if Ekind (Array_Type) = E_String_Literal_Subtype then
8997 Index_Type := Etype (String_Literal_Low_Bound (Array_Type));
8998 else
8999 Index_Type := Etype (First_Index (Array_Type));
9000 end if;
9001
9002 Resolve (Drange, Base_Type (Index_Type));
996ae0b0 9003
dbe945f1
AC		 9004 if Nkind (Drange) = N_Range then
9005
9006 -- Ensure that side effects in the bounds are properly handled
9007
cae81f17
JM		 9008 Force_Evaluation (Low_Bound (Drange));
9009 Force_Evaluation (High_Bound (Drange));
0669bebe
GB		 9010
9011 -- Do not apply the range check to nodes associated with the
9012 -- frontend expansion of the dispatch table. We first check
dbe945f1 9013 -- if Ada.Tags is already loaded to avoid the addition of an
0669bebe
GB		 9014 -- undesired dependence on such run-time unit.
9015
dbe945f1
AC		 9016 if not Tagged_Type_Expansion
9017 or else not
9018 (RTU_Loaded (Ada_Tags)
cead616d
AC		 9019 and then Nkind (Prefix (N)) = N_Selected_Component
9020 and then Present (Entity (Selector_Name (Prefix (N))))
9021 and then Entity (Selector_Name (Prefix (N))) =
dbe945f1
AC		 9022 RTE_Record_Component (RE_Prims_Ptr))
9023 then
5f44f0d4 9024 Apply_Range_Check (Drange, Index_Type);
dbe945f1 9025 end if;
996ae0b0
RK		 9026 end if;
9027 end if;
9028
9029 Set_Slice_Subtype (N);
aa180613 9030
ea034236
AC		 9031 -- Check bad use of type with predicates
9032
9033 if Has_Predicates (Etype (Drange)) then
ed00f472 9034 Bad_Predicated_Subtype_Use
ea034236
AC		 9035 ("subtype& has predicate, not allowed in slice",
9036 Drange, Etype (Drange));
9037
9038 -- Otherwise here is where we check suspicious indexes
9039
9040 elsif Nkind (Drange) = N_Range then
aa180613
RD		 9041 Warn_On_Suspicious_Index (Name, Low_Bound (Drange));
9042 Warn_On_Suspicious_Index (Name, High_Bound (Drange));
9043 end if;
9044
dec6faf1 9045 Analyze_Dimension (N);
996ae0b0 9046 Eval_Slice (N);
996ae0b0
RK		 9047 end Resolve_Slice;
9048
9049 ----------------------------
9050 -- Resolve_String_Literal --
9051 ----------------------------
9052
9053 procedure Resolve_String_Literal (N : Node_Id; Typ : Entity_Id) is
9054 C_Typ : constant Entity_Id := Component_Type (Typ);
9055 R_Typ : constant Entity_Id := Root_Type (C_Typ);
9056 Loc : constant Source_Ptr := Sloc (N);
9057 Str : constant String_Id := Strval (N);
9058 Strlen : constant Nat := String_Length (Str);
9059 Subtype_Id : Entity_Id;
9060 Need_Check : Boolean;
9061
9062 begin
9063 -- For a string appearing in a concatenation, defer creation of the
9064 -- string_literal_subtype until the end of the resolution of the
c8ef728f
ES		 9065 -- concatenation, because the literal may be constant-folded away. This
9066 -- is a useful optimization for long concatenation expressions.
996ae0b0 9067
c8ef728f 9068 -- If the string is an aggregate built for a single character (which
996ae0b0 9069 -- happens in a non-static context) or a is null string to which special
c8ef728f
ES		 9070 -- checks may apply, we build the subtype. Wide strings must also get a
9071 -- string subtype if they come from a one character aggregate. Strings
996ae0b0
RK		 9072 -- generated by attributes might be static, but it is often hard to
9073 -- determine whether the enclosing context is static, so we generate
9074 -- subtypes for them as well, thus losing some rarer optimizations ???
9075 -- Same for strings that come from a static conversion.
9076
9077 Need_Check :=
9078 (Strlen = 0 and then Typ /= Standard_String)
9079 or else Nkind (Parent (N)) /= N_Op_Concat
9080 or else (N /= Left_Opnd (Parent (N))
9081 and then N /= Right_Opnd (Parent (N)))
82c80734
RD		 9082 or else ((Typ = Standard_Wide_String
9083 or else Typ = Standard_Wide_Wide_String)
996ae0b0
RK		 9084 and then Nkind (Original_Node (N)) /= N_String_Literal);
9085
d81b4bfe
TQ		 9086 -- If the resolving type is itself a string literal subtype, we can just
9087 -- reuse it, since there is no point in creating another.
996ae0b0
RK		 9088
9089 if Ekind (Typ) = E_String_Literal_Subtype then
9090 Subtype_Id := Typ;
9091
9092 elsif Nkind (Parent (N)) = N_Op_Concat
9093 and then not Need_Check
45fc7ddb
HK		 9094 and then not Nkind_In (Original_Node (N), N_Character_Literal,
9095 N_Attribute_Reference,
9096 N_Qualified_Expression,
9097 N_Type_Conversion)
996ae0b0
RK		 9098 then
9099 Subtype_Id := Typ;
9100
9101 -- Otherwise we must create a string literal subtype. Note that the
9102 -- whole idea of string literal subtypes is simply to avoid the need
9103 -- for building a full fledged array subtype for each literal.
45fc7ddb 9104
996ae0b0
RK		 9105 else
9106 Set_String_Literal_Subtype (N, Typ);
9107 Subtype_Id := Etype (N);
9108 end if;
9109
9110 if Nkind (Parent (N)) /= N_Op_Concat
9111 or else Need_Check
9112 then
9113 Set_Etype (N, Subtype_Id);
9114 Eval_String_Literal (N);
9115 end if;
9116
9117 if Is_Limited_Composite (Typ)
9118 or else Is_Private_Composite (Typ)
9119 then
9120 Error_Msg_N ("string literal not available for private array", N);
9121 Set_Etype (N, Any_Type);
9122 return;
9123 end if;
9124
d81b4bfe
TQ		 9125 -- The validity of a null string has been checked in the call to
9126 -- Eval_String_Literal.
996ae0b0
RK		 9127
9128 if Strlen = 0 then
9129 return;
9130
c8ef728f
ES		 9131 -- Always accept string literal with component type Any_Character, which
9132 -- occurs in error situations and in comparisons of literals, both of
9133 -- which should accept all literals.
996ae0b0
RK		 9134
9135 elsif R_Typ = Any_Character then
9136 return;
9137
f3d57416
RW		 9138 -- If the type is bit-packed, then we always transform the string
9139 -- literal into a full fledged aggregate.
996ae0b0
RK		 9140
9141 elsif Is_Bit_Packed_Array (Typ) then
9142 null;
9143
82c80734 9144 -- Deal with cases of Wide_Wide_String, Wide_String, and String
996ae0b0
RK		 9145
9146 else
82c80734
RD		 9147 -- For Standard.Wide_Wide_String, or any other type whose component
9148 -- type is Standard.Wide_Wide_Character, we know that all the
996ae0b0
RK		 9149 -- characters in the string must be acceptable, since the parser
9150 -- accepted the characters as valid character literals.
9151
82c80734 9152 if R_Typ = Standard_Wide_Wide_Character then
996ae0b0
RK		 9153 null;
9154
c8ef728f
ES		 9155 -- For the case of Standard.String, or any other type whose component
9156 -- type is Standard.Character, we must make sure that there are no
9157 -- wide characters in the string, i.e. that it is entirely composed
9158 -- of characters in range of type Character.
996ae0b0 9159
c8ef728f
ES		 9160 -- If the string literal is the result of a static concatenation, the
9161 -- test has already been performed on the components, and need not be
9162 -- repeated.
996ae0b0
RK		 9163
9164 elsif R_Typ = Standard_Character
9165 and then Nkind (Original_Node (N)) /= N_Op_Concat
9166 then
9167 for J in 1 .. Strlen loop
9168 if not In_Character_Range (Get_String_Char (Str, J)) then
9169
9170 -- If we are out of range, post error. This is one of the
9171 -- very few places that we place the flag in the middle of
d81b4bfe
TQ		 9172 -- a token, right under the offending wide character. Not
9173 -- quite clear if this is right wrt wide character encoding
9174 -- sequences, but it's only an error message!
996ae0b0
RK		 9175
9176 Error_Msg
82c80734
RD		 9177 ("literal out of range of type Standard.Character",
9178 Source_Ptr (Int (Loc) + J));
9179 return;
9180 end if;
9181 end loop;
9182
9183 -- For the case of Standard.Wide_String, or any other type whose
9184 -- component type is Standard.Wide_Character, we must make sure that
9185 -- there are no wide characters in the string, i.e. that it is
9186 -- entirely composed of characters in range of type Wide_Character.
9187
9188 -- If the string literal is the result of a static concatenation,
9189 -- the test has already been performed on the components, and need
9190 -- not be repeated.
9191
9192 elsif R_Typ = Standard_Wide_Character
9193 and then Nkind (Original_Node (N)) /= N_Op_Concat
9194 then
9195 for J in 1 .. Strlen loop
9196 if not In_Wide_Character_Range (Get_String_Char (Str, J)) then
9197
9198 -- If we are out of range, post error. This is one of the
9199 -- very few places that we place the flag in the middle of
9200 -- a token, right under the offending wide character.
9201
9202 -- This is not quite right, because characters in general
9203 -- will take more than one character position ???
9204
9205 Error_Msg
9206 ("literal out of range of type Standard.Wide_Character",
996ae0b0
RK		 9207 Source_Ptr (Int (Loc) + J));
9208 return;
9209 end if;
9210 end loop;
9211
9212 -- If the root type is not a standard character, then we will convert
9213 -- the string into an aggregate and will let the aggregate code do
82c80734 9214 -- the checking. Standard Wide_Wide_Character is also OK here.
996ae0b0
RK		 9215
9216 else
9217 null;
996ae0b0
RK		 9218 end if;
9219
c8ef728f
ES		 9220 -- See if the component type of the array corresponding to the string
9221 -- has compile time known bounds. If yes we can directly check
9222 -- whether the evaluation of the string will raise constraint error.
9223 -- Otherwise we need to transform the string literal into the
5cc9353d
RD		 9224 -- corresponding character aggregate and let the aggregate code do
9225 -- the checking.
996ae0b0 9226
45fc7ddb
HK		 9227 if Is_Standard_Character_Type (R_Typ) then
9228
996ae0b0
RK		 9229 -- Check for the case of full range, where we are definitely OK
9230
9231 if Component_Type (Typ) = Base_Type (Component_Type (Typ)) then
9232 return;
9233 end if;
9234
9235 -- Here the range is not the complete base type range, so check
9236
9237 declare
9238 Comp_Typ_Lo : constant Node_Id :=
9239 Type_Low_Bound (Component_Type (Typ));
9240 Comp_Typ_Hi : constant Node_Id :=
9241 Type_High_Bound (Component_Type (Typ));
9242
9243 Char_Val : Uint;
9244
9245 begin
9246 if Compile_Time_Known_Value (Comp_Typ_Lo)
9247 and then Compile_Time_Known_Value (Comp_Typ_Hi)
9248 then
9249 for J in 1 .. Strlen loop
9250 Char_Val := UI_From_Int (Int (Get_String_Char (Str, J)));
9251
9252 if Char_Val < Expr_Value (Comp_Typ_Lo)
9253 or else Char_Val > Expr_Value (Comp_Typ_Hi)
9254 then
9255 Apply_Compile_Time_Constraint_Error
07fc65c4 9256 (N, "character out of range?", CE_Range_Check_Failed,
996ae0b0
RK		 9257 Loc => Source_Ptr (Int (Loc) + J));
9258 end if;
9259 end loop;
9260
9261 return;
9262 end if;
9263 end;
9264 end if;
9265 end if;
9266
9267 -- If we got here we meed to transform the string literal into the
9268 -- equivalent qualified positional array aggregate. This is rather
9269 -- heavy artillery for this situation, but it is hard work to avoid.
9270
9271 declare
fbf5a39b 9272 Lits : constant List_Id := New_List;
996ae0b0
RK		 9273 P : Source_Ptr := Loc + 1;
9274 C : Char_Code;
9275
9276 begin
c8ef728f
ES		 9277 -- Build the character literals, we give them source locations that
9278 -- correspond to the string positions, which is a bit tricky given
9279 -- the possible presence of wide character escape sequences.
996ae0b0
RK		 9280
9281 for J in 1 .. Strlen loop
9282 C := Get_String_Char (Str, J);
9283 Set_Character_Literal_Name (C);
9284
9285 Append_To (Lits,
82c80734
RD		 9286 Make_Character_Literal (P,
9287 Chars => Name_Find,
9288 Char_Literal_Value => UI_From_CC (C)));
996ae0b0
RK		 9289
9290 if In_Character_Range (C) then
9291 P := P + 1;
9292
9293 -- Should we have a call to Skip_Wide here ???
5cc9353d 9294
996ae0b0
RK		 9295 -- ??? else
9296 -- Skip_Wide (P);
9297
9298 end if;
9299 end loop;
9300
9301 Rewrite (N,
9302 Make_Qualified_Expression (Loc,
9303 Subtype_Mark => New_Reference_To (Typ, Loc),
9304 Expression =>
9305 Make_Aggregate (Loc, Expressions => Lits)));
9306
9307 Analyze_And_Resolve (N, Typ);
9308 end;
9309 end Resolve_String_Literal;
9310
9311 -----------------------------
9312 -- Resolve_Subprogram_Info --
9313 -----------------------------
9314
9315 procedure Resolve_Subprogram_Info (N : Node_Id; Typ : Entity_Id) is
9316 begin
9317 Set_Etype (N, Typ);
9318 end Resolve_Subprogram_Info;
9319
9320 -----------------------------
9321 -- Resolve_Type_Conversion --
9322 -----------------------------
9323
9324 procedure Resolve_Type_Conversion (N : Node_Id; Typ : Entity_Id) is
4b2d2c13
AC		 9325 Conv_OK : constant Boolean := Conversion_OK (N);
9326 Operand : constant Node_Id := Expression (N);
b7d1f17f
HK		 9327 Operand_Typ : constant Entity_Id := Etype (Operand);
9328 Target_Typ : constant Entity_Id := Etype (N);
996ae0b0 9329 Rop : Node_Id;
fbf5a39b
AC		 9330 Orig_N : Node_Id;
9331 Orig_T : Node_Id;
996ae0b0 9332
ae2aa109
AC		 9333 Test_Redundant : Boolean := Warn_On_Redundant_Constructs;
9334 -- Set to False to suppress cases where we want to suppress the test
9335 -- for redundancy to avoid possible false positives on this warning.
9336
996ae0b0 9337 begin
996ae0b0 9338 if not Conv_OK
b7d1f17f 9339 and then not Valid_Conversion (N, Target_Typ, Operand)
996ae0b0
RK		 9340 then
9341 return;
9342 end if;
9343
ae2aa109
AC		 9344 -- If the Operand Etype is Universal_Fixed, then the conversion is
9345 -- never redundant. We need this check because by the time we have
9346 -- finished the rather complex transformation, the conversion looks
9347 -- redundant when it is not.
9348
9349 if Operand_Typ = Universal_Fixed then
9350 Test_Redundant := False;
9351
9352 -- If the operand is marked as Any_Fixed, then special processing is
9353 -- required. This is also a case where we suppress the test for a
9354 -- redundant conversion, since most certainly it is not redundant.
9355
9356 elsif Operand_Typ = Any_Fixed then
9357 Test_Redundant := False;
996ae0b0
RK		 9358
9359 -- Mixed-mode operation involving a literal. Context must be a fixed
9360 -- type which is applied to the literal subsequently.
9361
9362 if Is_Fixed_Point_Type (Typ) then
9363 Set_Etype (Operand, Universal_Real);
9364
9365 elsif Is_Numeric_Type (Typ)
45fc7ddb 9366 and then Nkind_In (Operand, N_Op_Multiply, N_Op_Divide)
996ae0b0 9367 and then (Etype (Right_Opnd (Operand)) = Universal_Real
45fc7ddb
HK		 9368 or else
9369 Etype (Left_Opnd (Operand)) = Universal_Real)
996ae0b0 9370 then
a77842bd
TQ		 9371 -- Return if expression is ambiguous
9372
996ae0b0 9373 if Unique_Fixed_Point_Type (N) = Any_Type then
a77842bd 9374 return;
82c80734 9375
a77842bd
TQ		 9376 -- If nothing else, the available fixed type is Duration
9377
9378 else
996ae0b0
RK		 9379 Set_Etype (Operand, Standard_Duration);
9380 end if;
9381
bc5f3720 9382 -- Resolve the real operand with largest available precision
9ebe3743 9383
996ae0b0
RK		 9384 if Etype (Right_Opnd (Operand)) = Universal_Real then
9385 Rop := New_Copy_Tree (Right_Opnd (Operand));
9386 else
9387 Rop := New_Copy_Tree (Left_Opnd (Operand));
9388 end if;
9389
9ebe3743 9390 Resolve (Rop, Universal_Real);
996ae0b0 9391
82c80734
RD		 9392 -- If the operand is a literal (it could be a non-static and
9393 -- illegal exponentiation) check whether the use of Duration
9394 -- is potentially inaccurate.
9395
9396 if Nkind (Rop) = N_Real_Literal
9397 and then Realval (Rop) /= Ureal_0
996ae0b0
RK		 9398 and then abs (Realval (Rop)) < Delta_Value (Standard_Duration)
9399 then
aa180613 9400 Error_Msg_N
aa5147f0
ES		 9401 ("?universal real operand can only " &
9402 "be interpreted as Duration!",
aa180613
RD		 9403 Rop);
9404 Error_Msg_N
aa5147f0 9405 ("\?precision will be lost in the conversion!", Rop);
996ae0b0
RK		 9406 end if;
9407
891a6e79
AC		 9408 elsif Is_Numeric_Type (Typ)
9409 and then Nkind (Operand) in N_Op
9410 and then Unique_Fixed_Point_Type (N) /= Any_Type
9411 then
9412 Set_Etype (Operand, Standard_Duration);
9413
996ae0b0
RK		 9414 else
9415 Error_Msg_N ("invalid context for mixed mode operation", N);
9416 Set_Etype (Operand, Any_Type);
9417 return;
9418 end if;
9419 end if;
9420
fbf5a39b 9421 Resolve (Operand);
996ae0b0 9422
2ba431e5
YM		 9423 -- In SPARK, a type conversion between array types should be restricted
9424 -- to types which have matching static bounds.
b0186f71 9425
7b98672f
YM		 9426 -- Protect call to Matching_Static_Array_Bounds to avoid costly
9427 -- operation if not needed.
9428
9429 if Restriction_Check_Required (SPARK)
9430 and then Is_Array_Type (Target_Typ)
b0186f71 9431 and then Is_Array_Type (Operand_Typ)
db72f10a 9432 and then Operand_Typ /= Any_Composite -- or else Operand in error
b0186f71
AC		 9433 and then not Matching_Static_Array_Bounds (Target_Typ, Operand_Typ)
9434 then
2ba431e5 9435 Check_SPARK_Restriction
fe5d3068 9436 ("array types should have matching static bounds", N);
b0186f71
AC		 9437 end if;
9438
e24329cd
YM		 9439 -- In formal mode, the operand of an ancestor type conversion must be an
9440 -- object (not an expression).
9441
9442 if Is_Tagged_Type (Target_Typ)
9443 and then not Is_Class_Wide_Type (Target_Typ)
9444 and then Is_Tagged_Type (Operand_Typ)
9445 and then not Is_Class_Wide_Type (Operand_Typ)
9446 and then Is_Ancestor (Target_Typ, Operand_Typ)
9447 and then not Is_SPARK_Object_Reference (Operand)
9448 then
2ba431e5 9449 Check_SPARK_Restriction ("object required", Operand);
e24329cd
YM		 9450 end if;
9451
dec6faf1
AC		 9452 Analyze_Dimension (N);
9453
996ae0b0 9454 -- Note: we do the Eval_Type_Conversion call before applying the
d81b4bfe
TQ		 9455 -- required checks for a subtype conversion. This is important, since
9456 -- both are prepared under certain circumstances to change the type
9457 -- conversion to a constraint error node, but in the case of
9458 -- Eval_Type_Conversion this may reflect an illegality in the static
9459 -- case, and we would miss the illegality (getting only a warning
9460 -- message), if we applied the type conversion checks first.
996ae0b0
RK		 9461
9462 Eval_Type_Conversion (N);
9463
d81b4bfe
TQ		 9464 -- Even when evaluation is not possible, we may be able to simplify the
9465 -- conversion or its expression. This needs to be done before applying
9466 -- checks, since otherwise the checks may use the original expression
9467 -- and defeat the simplifications. This is specifically the case for
9468 -- elimination of the floating-point Truncation attribute in
9469 -- float-to-int conversions.
0669bebe
GB		 9470
9471 Simplify_Type_Conversion (N);
9472
d81b4bfe
TQ		 9473 -- If after evaluation we still have a type conversion, then we may need
9474 -- to apply checks required for a subtype conversion.
996ae0b0
RK		 9475
9476 -- Skip these type conversion checks if universal fixed operands
9477 -- operands involved, since range checks are handled separately for
9478 -- these cases (in the appropriate Expand routines in unit Exp_Fixd).
9479
9480 if Nkind (N) = N_Type_Conversion
b7d1f17f
HK		 9481 and then not Is_Generic_Type (Root_Type (Target_Typ))
9482 and then Target_Typ /= Universal_Fixed
9483 and then Operand_Typ /= Universal_Fixed
996ae0b0
RK		 9484 then
9485 Apply_Type_Conversion_Checks (N);
9486 end if;
9487
d81b4bfe
TQ		 9488 -- Issue warning for conversion of simple object to its own type. We
9489 -- have to test the original nodes, since they may have been rewritten
9490 -- by various optimizations.
fbf5a39b
AC		 9491
9492 Orig_N := Original_Node (N);
996ae0b0 9493
ae2aa109
AC		 9494 -- Here we test for a redundant conversion if the warning mode is
9495 -- active (and was not locally reset), and we have a type conversion
9496 -- from source not appearing in a generic instance.
9497
9498 if Test_Redundant
fbf5a39b 9499 and then Nkind (Orig_N) = N_Type_Conversion
ae2aa109 9500 and then Comes_From_Source (Orig_N)
5453d5bd 9501 and then not In_Instance
996ae0b0 9502 then
fbf5a39b 9503 Orig_N := Original_Node (Expression (Orig_N));
b7d1f17f 9504 Orig_T := Target_Typ;
fbf5a39b
AC		 9505
9506 -- If the node is part of a larger expression, the Target_Type
9507 -- may not be the original type of the node if the context is a
9508 -- condition. Recover original type to see if conversion is needed.
9509
9510 if Is_Boolean_Type (Orig_T)
9511 and then Nkind (Parent (N)) in N_Op
9512 then
9513 Orig_T := Etype (Parent (N));
9514 end if;
9515
4adf3c50 9516 -- If we have an entity name, then give the warning if the entity
ae2aa109
AC		 9517 -- is the right type, or if it is a loop parameter covered by the
9518 -- original type (that's needed because loop parameters have an
9519 -- odd subtype coming from the bounds).
9520
9521 if (Is_Entity_Name (Orig_N)
9522 and then
9523 (Etype (Entity (Orig_N)) = Orig_T
9524 or else
9525 (Ekind (Entity (Orig_N)) = E_Loop_Parameter
477bd732 9526 and then Covers (Orig_T, Etype (Entity (Orig_N))))))
ae2aa109 9527
477bd732 9528 -- If not an entity, then type of expression must match
ae2aa109
AC		 9529
9530 or else Etype (Orig_N) = Orig_T
fbf5a39b 9531 then
4b2d2c13
AC		 9532 -- One more check, do not give warning if the analyzed conversion
9533 -- has an expression with non-static bounds, and the bounds of the
9534 -- target are static. This avoids junk warnings in cases where the
9535 -- conversion is necessary to establish staticness, for example in
9536 -- a case statement.
9537
9538 if not Is_OK_Static_Subtype (Operand_Typ)
9539 and then Is_OK_Static_Subtype (Target_Typ)
9540 then
9541 null;
9542
5cc9353d
RD		 9543 -- Finally, if this type conversion occurs in a context requiring
9544 -- a prefix, and the expression is a qualified expression then the
9545 -- type conversion is not redundant, since a qualified expression
9546 -- is not a prefix, whereas a type conversion is. For example, "X
9547 -- := T'(Funx(...)).Y;" is illegal because a selected component
9548 -- requires a prefix, but a type conversion makes it legal: "X :=
9549 -- T(T'(Funx(...))).Y;"
4adf3c50 9550
9db0b232
AC		 9551 -- In Ada 2012, a qualified expression is a name, so this idiom is
9552 -- no longer needed, but we still suppress the warning because it
9553 -- seems unfriendly for warnings to pop up when you switch to the
9554 -- newer language version.
be257e99
AC		 9555
9556 elsif Nkind (Orig_N) = N_Qualified_Expression
f5d96d00
AC		 9557 and then Nkind_In (Parent (N), N_Attribute_Reference,
9558 N_Indexed_Component,
9559 N_Selected_Component,
9560 N_Slice,
9561 N_Explicit_Dereference)
be257e99
AC		 9562 then
9563 null;
9564
ae2aa109
AC		 9565 -- Here we give the redundant conversion warning. If it is an
9566 -- entity, give the name of the entity in the message. If not,
9567 -- just mention the expression.
4b2d2c13
AC		 9568
9569 else
ae2aa109
AC		 9570 if Is_Entity_Name (Orig_N) then
9571 Error_Msg_Node_2 := Orig_T;
9572 Error_Msg_NE -- CODEFIX
9573 ("?redundant conversion, & is of type &!",
9574 N, Entity (Orig_N));
9575 else
9576 Error_Msg_NE
9577 ("?redundant conversion, expression is of type&!",
9578 N, Orig_T);
9579 end if;
4b2d2c13 9580 end if;
fbf5a39b 9581 end if;
996ae0b0 9582 end if;
758c442c 9583
b7d1f17f 9584 -- Ada 2005 (AI-251): Handle class-wide interface type conversions.
0669bebe
GB		 9585 -- No need to perform any interface conversion if the type of the
9586 -- expression coincides with the target type.
758c442c 9587
0791fbe9 9588 if Ada_Version >= Ada_2005
11fa950b 9589 and then Full_Expander_Active
b7d1f17f 9590 and then Operand_Typ /= Target_Typ
0669bebe 9591 then
b7d1f17f
HK		 9592 declare
9593 Opnd : Entity_Id := Operand_Typ;
9594 Target : Entity_Id := Target_Typ;
758c442c 9595
b7d1f17f
HK		 9596 begin
9597 if Is_Access_Type (Opnd) then
841dd0f5 9598 Opnd := Designated_Type (Opnd);
1420b484
JM		 9599 end if;
9600
b7d1f17f 9601 if Is_Access_Type (Target_Typ) then
841dd0f5 9602 Target := Designated_Type (Target);
4197ae1e 9603 end if;
c8ef728f 9604
b7d1f17f
HK		 9605 if Opnd = Target then
9606 null;
c8ef728f 9607
b7d1f17f 9608 -- Conversion from interface type
ea985d95 9609
b7d1f17f 9610 elsif Is_Interface (Opnd) then
ea985d95 9611
b7d1f17f 9612 -- Ada 2005 (AI-217): Handle entities from limited views
aa180613 9613
b7d1f17f
HK		 9614 if From_With_Type (Opnd) then
9615 Error_Msg_Qual_Level := 99;
305caf42
AC		 9616 Error_Msg_NE -- CODEFIX
9617 ("missing WITH clause on package &", N,
b7d1f17f
HK		 9618 Cunit_Entity (Get_Source_Unit (Base_Type (Opnd))));
9619 Error_Msg_N
9620 ("type conversions require visibility of the full view",
9621 N);
aa180613 9622
aa5147f0
ES		 9623 elsif From_With_Type (Target)
9624 and then not
9625 (Is_Access_Type (Target_Typ)
9626 and then Present (Non_Limited_View (Etype (Target))))
9627 then
b7d1f17f 9628 Error_Msg_Qual_Level := 99;
305caf42
AC		 9629 Error_Msg_NE -- CODEFIX
9630 ("missing WITH clause on package &", N,
b7d1f17f
HK		 9631 Cunit_Entity (Get_Source_Unit (Base_Type (Target))));
9632 Error_Msg_N
9633 ("type conversions require visibility of the full view",
9634 N);
aa180613 9635
b7d1f17f
HK		 9636 else
9637 Expand_Interface_Conversion (N, Is_Static => False);
9638 end if;
9639
9640 -- Conversion to interface type
9641
9642 elsif Is_Interface (Target) then
9643
9644 -- Handle subtypes
9645
8a95f4e8 9646 if Ekind_In (Opnd, E_Protected_Subtype, E_Task_Subtype) then
b7d1f17f
HK		 9647 Opnd := Etype (Opnd);
9648 end if;
9649
9650 if not Interface_Present_In_Ancestor
9651 (Typ => Opnd,
9652 Iface => Target)
9653 then
9654 if Is_Class_Wide_Type (Opnd) then
9655
9656 -- The static analysis is not enough to know if the
9657 -- interface is implemented or not. Hence we must pass
9658 -- the work to the expander to generate code to evaluate
e7c0dd39 9659 -- the conversion at run time.
b7d1f17f
HK		 9660
9661 Expand_Interface_Conversion (N, Is_Static => False);
9662
9663 else
9664 Error_Msg_Name_1 := Chars (Etype (Target));
9665 Error_Msg_Name_2 := Chars (Opnd);
9666 Error_Msg_N
9667 ("wrong interface conversion (% is not a progenitor " &
9668 "of %)", N);
9669 end if;
9670
9671 else
9672 Expand_Interface_Conversion (N);
9673 end if;
9674 end if;
9675 end;
758c442c 9676 end if;
996ae0b0
RK		 9677 end Resolve_Type_Conversion;
9678
9679 ----------------------
9680 -- Resolve_Unary_Op --
9681 ----------------------
9682
9683 procedure Resolve_Unary_Op (N : Node_Id; Typ : Entity_Id) is
fbf5a39b
AC		 9684 B_Typ : constant Entity_Id := Base_Type (Typ);
9685 R : constant Node_Id := Right_Opnd (N);
9686 OK : Boolean;
9687 Lo : Uint;
9688 Hi : Uint;
996ae0b0
RK		 9689
9690 begin
7a489a2b
AC		 9691 if Is_Modular_Integer_Type (Typ) and then Nkind (N) /= N_Op_Not then
9692 Error_Msg_Name_1 := Chars (Typ);
2ba431e5 9693 Check_SPARK_Restriction
7a489a2b
AC		 9694 ("unary operator not defined for modular type%", N);
9695 end if;
9696
b7d1f17f 9697 -- Deal with intrinsic unary operators
996ae0b0 9698
fbf5a39b
AC		 9699 if Comes_From_Source (N)
9700 and then Ekind (Entity (N)) = E_Function
9701 and then Is_Imported (Entity (N))
9702 and then Is_Intrinsic_Subprogram (Entity (N))
9703 then
9704 Resolve_Intrinsic_Unary_Operator (N, Typ);
9705 return;
9706 end if;
9707
0669bebe
GB		 9708 -- Deal with universal cases
9709
996ae0b0 9710 if Etype (R) = Universal_Integer
0669bebe
GB		 9711 or else
9712 Etype (R) = Universal_Real
996ae0b0
RK		 9713 then
9714 Check_For_Visible_Operator (N, B_Typ);
9715 end if;
9716
9717 Set_Etype (N, B_Typ);
9718 Resolve (R, B_Typ);
fbf5a39b 9719
9ebe3743
HK		 9720 -- Generate warning for expressions like abs (x mod 2)
9721
9722 if Warn_On_Redundant_Constructs
9723 and then Nkind (N) = N_Op_Abs
9724 then
9725 Determine_Range (Right_Opnd (N), OK, Lo, Hi);
9726
9727 if OK and then Hi >= Lo and then Lo >= 0 then
305caf42 9728 Error_Msg_N -- CODEFIX
9ebe3743
HK		 9729 ("?abs applied to known non-negative value has no effect", N);
9730 end if;
9731 end if;
9732
0669bebe
GB		 9733 -- Deal with reference generation
9734
996ae0b0 9735 Check_Unset_Reference (R);
fbf5a39b 9736 Generate_Operator_Reference (N, B_Typ);
dec6faf1 9737 Analyze_Dimension (N);
996ae0b0
RK		 9738 Eval_Unary_Op (N);
9739
9740 -- Set overflow checking bit. Much cleverer code needed here eventually
9741 -- and perhaps the Resolve routines should be separated for the various
9742 -- arithmetic operations, since they will need different processing ???
9743
9744 if Nkind (N) in N_Op then
9745 if not Overflow_Checks_Suppressed (Etype (N)) then
fbf5a39b 9746 Enable_Overflow_Check (N);
996ae0b0
RK		 9747 end if;
9748 end if;
0669bebe 9749
d81b4bfe
TQ		 9750 -- Generate warning for expressions like -5 mod 3 for integers. No need
9751 -- to worry in the floating-point case, since parens do not affect the
9752 -- result so there is no point in giving in a warning.
0669bebe
GB		 9753
9754 declare
9755 Norig : constant Node_Id := Original_Node (N);
9756 Rorig : Node_Id;
9757 Val : Uint;
9758 HB : Uint;
9759 LB : Uint;
9760 Lval : Uint;
9761 Opnd : Node_Id;
9762
9763 begin
9764 if Warn_On_Questionable_Missing_Parens
9765 and then Comes_From_Source (Norig)
9766 and then Is_Integer_Type (Typ)
9767 and then Nkind (Norig) = N_Op_Minus
9768 then
9769 Rorig := Original_Node (Right_Opnd (Norig));
9770
9771 -- We are looking for cases where the right operand is not
f3d57416 9772 -- parenthesized, and is a binary operator, multiply, divide, or
0669bebe
GB		 9773 -- mod. These are the cases where the grouping can affect results.
9774
9775 if Paren_Count (Rorig) = 0
45fc7ddb 9776 and then Nkind_In (Rorig, N_Op_Mod, N_Op_Multiply, N_Op_Divide)
0669bebe
GB		 9777 then
9778 -- For mod, we always give the warning, since the value is
9779 -- affected by the parenthesization (e.g. (-5) mod 315 /=
d81b4bfe 9780 -- -(5 mod 315)). But for the other cases, the only concern is
0669bebe
GB		 9781 -- overflow, e.g. for the case of 8 big signed (-(2 * 64)
9782 -- overflows, but (-2) * 64 does not). So we try to give the
9783 -- message only when overflow is possible.
9784
9785 if Nkind (Rorig) /= N_Op_Mod
9786 and then Compile_Time_Known_Value (R)
9787 then
9788 Val := Expr_Value (R);
9789
9790 if Compile_Time_Known_Value (Type_High_Bound (Typ)) then
9791 HB := Expr_Value (Type_High_Bound (Typ));
9792 else
9793 HB := Expr_Value (Type_High_Bound (Base_Type (Typ)));
9794 end if;
9795
9796 if Compile_Time_Known_Value (Type_Low_Bound (Typ)) then
9797 LB := Expr_Value (Type_Low_Bound (Typ));
9798 else
9799 LB := Expr_Value (Type_Low_Bound (Base_Type (Typ)));
9800 end if;
9801
d81b4bfe
TQ		 9802 -- Note that the test below is deliberately excluding the
9803 -- largest negative number, since that is a potentially
0669bebe
GB		 9804 -- troublesome case (e.g. -2 * x, where the result is the
9805 -- largest negative integer has an overflow with 2 * x).
9806
9807 if Val > LB and then Val <= HB then
9808 return;
9809 end if;
9810 end if;
9811
9812 -- For the multiplication case, the only case we have to worry
9813 -- about is when (-a)*b is exactly the largest negative number
9814 -- so that -(a*b) can cause overflow. This can only happen if
9815 -- a is a power of 2, and more generally if any operand is a
9816 -- constant that is not a power of 2, then the parentheses
9817 -- cannot affect whether overflow occurs. We only bother to
9818 -- test the left most operand
9819
9820 -- Loop looking at left operands for one that has known value
9821
9822 Opnd := Rorig;
9823 Opnd_Loop : while Nkind (Opnd) = N_Op_Multiply loop
9824 if Compile_Time_Known_Value (Left_Opnd (Opnd)) then
9825 Lval := UI_Abs (Expr_Value (Left_Opnd (Opnd)));
9826
9827 -- Operand value of 0 or 1 skips warning
9828
9829 if Lval <= 1 then
9830 return;
9831
9832 -- Otherwise check power of 2, if power of 2, warn, if
9833 -- anything else, skip warning.
9834
9835 else
9836 while Lval /= 2 loop
9837 if Lval mod 2 = 1 then
9838 return;
9839 else
9840 Lval := Lval / 2;
9841 end if;
9842 end loop;
9843
9844 exit Opnd_Loop;
9845 end if;
9846 end if;
9847
9848 -- Keep looking at left operands
9849
9850 Opnd := Left_Opnd (Opnd);
9851 end loop Opnd_Loop;
9852
9853 -- For rem or "/" we can only have a problematic situation
9854 -- if the divisor has a value of minus one or one. Otherwise
9855 -- overflow is impossible (divisor > 1) or we have a case of
9856 -- division by zero in any case.
9857
45fc7ddb 9858 if Nkind_In (Rorig, N_Op_Divide, N_Op_Rem)
0669bebe
GB		 9859 and then Compile_Time_Known_Value (Right_Opnd (Rorig))
9860 and then UI_Abs (Expr_Value (Right_Opnd (Rorig))) /= 1
9861 then
9862 return;
9863 end if;
9864
9865 -- If we fall through warning should be issued
9866
ed2233dc 9867 Error_Msg_N
aa5147f0 9868 ("?unary minus expression should be parenthesized here!", N);
0669bebe
GB		 9869 end if;
9870 end if;
9871 end;
996ae0b0
RK		 9872 end Resolve_Unary_Op;
9873
9874 ----------------------------------
9875 -- Resolve_Unchecked_Expression --
9876 ----------------------------------
9877
9878 procedure Resolve_Unchecked_Expression
9879 (N : Node_Id;
9880 Typ : Entity_Id)
9881 is
9882 begin
9883 Resolve (Expression (N), Typ, Suppress => All_Checks);
9884 Set_Etype (N, Typ);
9885 end Resolve_Unchecked_Expression;
9886
9887 ---------------------------------------
9888 -- Resolve_Unchecked_Type_Conversion --
9889 ---------------------------------------
9890
9891 procedure Resolve_Unchecked_Type_Conversion
9892 (N : Node_Id;
9893 Typ : Entity_Id)
9894 is
07fc65c4
GB		 9895 pragma Warnings (Off, Typ);
9896
996ae0b0
RK		 9897 Operand : constant Node_Id := Expression (N);
9898 Opnd_Type : constant Entity_Id := Etype (Operand);
9899
9900 begin
a77842bd 9901 -- Resolve operand using its own type
996ae0b0
RK		 9902
9903 Resolve (Operand, Opnd_Type);
dec6faf1 9904 Analyze_Dimension (N);
996ae0b0 9905 Eval_Unchecked_Conversion (N);
996ae0b0
RK		 9906 end Resolve_Unchecked_Type_Conversion;
9907
9908 ------------------------------
9909 -- Rewrite_Operator_As_Call --
9910 ------------------------------
9911
9912 procedure Rewrite_Operator_As_Call (N : Node_Id; Nam : Entity_Id) is
fbf5a39b
AC		 9913 Loc : constant Source_Ptr := Sloc (N);
9914 Actuals : constant List_Id := New_List;
996ae0b0
RK		 9915 New_N : Node_Id;
9916
9917 begin
9918 if Nkind (N) in N_Binary_Op then
9919 Append (Left_Opnd (N), Actuals);
9920 end if;
9921
9922 Append (Right_Opnd (N), Actuals);
9923
9924 New_N :=
9925 Make_Function_Call (Sloc => Loc,
9926 Name => New_Occurrence_Of (Nam, Loc),
9927 Parameter_Associations => Actuals);
9928
9929 Preserve_Comes_From_Source (New_N, N);
9930 Preserve_Comes_From_Source (Name (New_N), N);
9931 Rewrite (N, New_N);
9932 Set_Etype (N, Etype (Nam));
9933 end Rewrite_Operator_As_Call;
9934
9935 ------------------------------
9936 -- Rewrite_Renamed_Operator --
9937 ------------------------------
9938
0ab80019
AC		 9939 procedure Rewrite_Renamed_Operator
9940 (N : Node_Id;
9941 Op : Entity_Id;
9942 Typ : Entity_Id)
9943 is
996ae0b0
RK		 9944 Nam : constant Name_Id := Chars (Op);
9945 Is_Binary : constant Boolean := Nkind (N) in N_Binary_Op;
9946 Op_Node : Node_Id;
9947
9948 begin
d81b4bfe
TQ		 9949 -- Rewrite the operator node using the real operator, not its renaming.
9950 -- Exclude user-defined intrinsic operations of the same name, which are
9951 -- treated separately and rewritten as calls.
996ae0b0 9952
964f13da 9953 if Ekind (Op) /= E_Function or else Chars (N) /= Nam then
996ae0b0
RK		 9954 Op_Node := New_Node (Operator_Kind (Nam, Is_Binary), Sloc (N));
9955 Set_Chars (Op_Node, Nam);
9956 Set_Etype (Op_Node, Etype (N));
9957 Set_Entity (Op_Node, Op);
9958 Set_Right_Opnd (Op_Node, Right_Opnd (N));
9959
b7d1f17f
HK		 9960 -- Indicate that both the original entity and its renaming are
9961 -- referenced at this point.
fbf5a39b
AC		 9962
9963 Generate_Reference (Entity (N), N);
996ae0b0
RK		 9964 Generate_Reference (Op, N);
9965
9966 if Is_Binary then
9967 Set_Left_Opnd (Op_Node, Left_Opnd (N));
9968 end if;
9969
9970 Rewrite (N, Op_Node);
0ab80019 9971
1366997b
AC		 9972 -- If the context type is private, add the appropriate conversions so
9973 -- that the operator is applied to the full view. This is done in the
9974 -- routines that resolve intrinsic operators.
0ab80019
AC		 9975
9976 if Is_Intrinsic_Subprogram (Op)
9977 and then Is_Private_Type (Typ)
9978 then
9979 case Nkind (N) is
9980 when N_Op_Add | N_Op_Subtract | N_Op_Multiply | N_Op_Divide |
9981 N_Op_Expon | N_Op_Mod | N_Op_Rem =>
9982 Resolve_Intrinsic_Operator (N, Typ);
9983
d81b4bfe 9984 when N_Op_Plus | N_Op_Minus | N_Op_Abs =>
0ab80019
AC		 9985 Resolve_Intrinsic_Unary_Operator (N, Typ);
9986
9987 when others =>
9988 Resolve (N, Typ);
9989 end case;
9990 end if;
9991
964f13da
RD		 9992 elsif Ekind (Op) = E_Function and then Is_Intrinsic_Subprogram (Op) then
9993
1366997b
AC		 9994 -- Operator renames a user-defined operator of the same name. Use the
9995 -- original operator in the node, which is the one Gigi knows about.
0ab80019
AC		 9996
9997 Set_Entity (N, Op);
9998 Set_Is_Overloaded (N, False);
996ae0b0
RK		 9999 end if;
10000 end Rewrite_Renamed_Operator;
10001
10002 -----------------------
10003 -- Set_Slice_Subtype --
10004 -----------------------
10005
1366997b
AC		 10006 -- Build an implicit subtype declaration to represent the type delivered by
10007 -- the slice. This is an abbreviated version of an array subtype. We define
10008 -- an index subtype for the slice, using either the subtype name or the
10009 -- discrete range of the slice. To be consistent with index usage elsewhere
10010 -- we create a list header to hold the single index. This list is not
10011 -- otherwise attached to the syntax tree.
996ae0b0
RK		 10012
10013 procedure Set_Slice_Subtype (N : Node_Id) is
10014 Loc : constant Source_Ptr := Sloc (N);
fbf5a39b 10015 Index_List : constant List_Id := New_List;
996ae0b0 10016 Index : Node_Id;
996ae0b0
RK		 10017 Index_Subtype : Entity_Id;
10018 Index_Type : Entity_Id;
10019 Slice_Subtype : Entity_Id;
10020 Drange : constant Node_Id := Discrete_Range (N);
10021
10022 begin
10023 if Is_Entity_Name (Drange) then
10024 Index_Subtype := Entity (Drange);
10025
10026 else
10027 -- We force the evaluation of a range. This is definitely needed in
10028 -- the renamed case, and seems safer to do unconditionally. Note in
10029 -- any case that since we will create and insert an Itype referring
10030 -- to this range, we must make sure any side effect removal actions
10031 -- are inserted before the Itype definition.
10032
10033 if Nkind (Drange) = N_Range then
10034 Force_Evaluation (Low_Bound (Drange));
10035 Force_Evaluation (High_Bound (Drange));
10036 end if;
10037
10038 Index_Type := Base_Type (Etype (Drange));
10039
10040 Index_Subtype := Create_Itype (Subtype_Kind (Ekind (Index_Type)), N);
10041
8a95f4e8 10042 -- Take a new copy of Drange (where bounds have been rewritten to
3c1ecd7e
AC		 10043 -- reference side-effect-free names). Using a separate tree ensures
10044 -- that further expansion (e.g. while rewriting a slice assignment
8a95f4e8
RD		 10045 -- into a FOR loop) does not attempt to remove side effects on the
10046 -- bounds again (which would cause the bounds in the index subtype
10047 -- definition to refer to temporaries before they are defined) (the
10048 -- reason is that some names are considered side effect free here
10049 -- for the subtype, but not in the context of a loop iteration
10050 -- scheme).
10051
10052 Set_Scalar_Range (Index_Subtype, New_Copy_Tree (Drange));
4230bdb7 10053 Set_Parent (Scalar_Range (Index_Subtype), Index_Subtype);
996ae0b0
RK		 10054 Set_Etype (Index_Subtype, Index_Type);
10055 Set_Size_Info (Index_Subtype, Index_Type);
10056 Set_RM_Size (Index_Subtype, RM_Size (Index_Type));
10057 end if;
10058
10059 Slice_Subtype := Create_Itype (E_Array_Subtype, N);
10060
10061 Index := New_Occurrence_Of (Index_Subtype, Loc);
10062 Set_Etype (Index, Index_Subtype);
10063 Append (Index, Index_List);
10064
996ae0b0
RK		 10065 Set_First_Index (Slice_Subtype, Index);
10066 Set_Etype (Slice_Subtype, Base_Type (Etype (N)));
10067 Set_Is_Constrained (Slice_Subtype, True);
996ae0b0 10068
8a95f4e8
RD		 10069 Check_Compile_Time_Size (Slice_Subtype);
10070
b7d1f17f
HK		 10071 -- The Etype of the existing Slice node is reset to this slice subtype.
10072 -- Its bounds are obtained from its first index.
996ae0b0
RK		 10073
10074 Set_Etype (N, Slice_Subtype);
10075
5cc9353d
RD		 10076 -- For packed slice subtypes, freeze immediately (except in the case of
10077 -- being in a "spec expression" where we never freeze when we first see
10078 -- the expression).
8a95f4e8
RD		 10079
10080 if Is_Packed (Slice_Subtype) and not In_Spec_Expression then
10081 Freeze_Itype (Slice_Subtype, N);
996ae0b0 10082
cfab0c49
AC		 10083 -- For all other cases insert an itype reference in the slice's actions
10084 -- so that the itype is frozen at the proper place in the tree (i.e. at
10085 -- the point where actions for the slice are analyzed). Note that this
10086 -- is different from freezing the itype immediately, which might be
6ff6152d
ES		 10087 -- premature (e.g. if the slice is within a transient scope). This needs
10088 -- to be done only if expansion is enabled.
cfab0c49 10089
11fa950b 10090 elsif Full_Expander_Active then
8a95f4e8
RD		 10091 Ensure_Defined (Typ => Slice_Subtype, N => N);
10092 end if;
996ae0b0
RK		 10093 end Set_Slice_Subtype;
10094
10095 --------------------------------
10096 -- Set_String_Literal_Subtype --
10097 --------------------------------
10098
10099 procedure Set_String_Literal_Subtype (N : Node_Id; Typ : Entity_Id) is
c8ef728f
ES		 10100 Loc : constant Source_Ptr := Sloc (N);
10101 Low_Bound : constant Node_Id :=
d81b4bfe 10102 Type_Low_Bound (Etype (First_Index (Typ)));
996ae0b0
RK		 10103 Subtype_Id : Entity_Id;
10104
10105 begin
10106 if Nkind (N) /= N_String_Literal then
10107 return;
996ae0b0
RK		 10108 end if;
10109
c8ef728f 10110 Subtype_Id := Create_Itype (E_String_Literal_Subtype, N);
91b1417d
AC		 10111 Set_String_Literal_Length (Subtype_Id, UI_From_Int
10112 (String_Length (Strval (N))));
c8ef728f
ES		 10113 Set_Etype (Subtype_Id, Base_Type (Typ));
10114 Set_Is_Constrained (Subtype_Id);
10115 Set_Etype (N, Subtype_Id);
10116
1366997b
AC		 10117 -- The low bound is set from the low bound of the corresponding index
10118 -- type. Note that we do not store the high bound in the string literal
10119 -- subtype, but it can be deduced if necessary from the length and the
10120 -- low bound.
996ae0b0 10121
5f44f0d4 10122 if Is_OK_Static_Expression (Low_Bound) then
c8ef728f 10123 Set_String_Literal_Low_Bound (Subtype_Id, Low_Bound);
996ae0b0 10124
5f44f0d4
AC		 10125 -- If the lower bound is not static we create a range for the string
10126 -- literal, using the index type and the known length of the literal.
10127 -- The index type is not necessarily Positive, so the upper bound is
10128 -- computed as T'Val (T'Pos (Low_Bound) + L - 1).
c8ef728f 10129
5f44f0d4 10130 else
c8ef728f 10131 declare
5f44f0d4
AC		 10132 Index_List : constant List_Id := New_List;
10133 Index_Type : constant Entity_Id := Etype (First_Index (Typ));
10134 High_Bound : constant Node_Id :=
53f29d4f
AC		 10135 Make_Attribute_Reference (Loc,
10136 Attribute_Name => Name_Val,
10137 Prefix =>
10138 New_Occurrence_Of (Index_Type, Loc),
10139 Expressions => New_List (
10140 Make_Op_Add (Loc,
10141 Left_Opnd =>
10142 Make_Attribute_Reference (Loc,
10143 Attribute_Name => Name_Pos,
10144 Prefix =>
10145 New_Occurrence_Of (Index_Type, Loc),
10146 Expressions =>
10147 New_List (New_Copy_Tree (Low_Bound))),
10148 Right_Opnd =>
10149 Make_Integer_Literal (Loc,
10150 String_Length (Strval (N)) - 1))));
c0b11850 10151
c8ef728f 10152 Array_Subtype : Entity_Id;
c8ef728f
ES		 10153 Drange : Node_Id;
10154 Index : Node_Id;
5f44f0d4 10155 Index_Subtype : Entity_Id;
c8ef728f
ES		 10156
10157 begin
56e94186
AC		 10158 if Is_Integer_Type (Index_Type) then
10159 Set_String_Literal_Low_Bound
10160 (Subtype_Id, Make_Integer_Literal (Loc, 1));
10161
10162 else
10163 -- If the index type is an enumeration type, build bounds
10164 -- expression with attributes.
10165
10166 Set_String_Literal_Low_Bound
10167 (Subtype_Id,
10168 Make_Attribute_Reference (Loc,
10169 Attribute_Name => Name_First,
10170 Prefix =>
10171 New_Occurrence_Of (Base_Type (Index_Type), Loc)));
10172 Set_Etype (String_Literal_Low_Bound (Subtype_Id), Index_Type);
10173 end if;
10174
c0b11850
AC		 10175 Analyze_And_Resolve (String_Literal_Low_Bound (Subtype_Id));
10176
10177 -- Build bona fide subtype for the string, and wrap it in an
10178 -- unchecked conversion, because the backend expects the
10179 -- String_Literal_Subtype to have a static lower bound.
10180
c8ef728f
ES		 10181 Index_Subtype :=
10182 Create_Itype (Subtype_Kind (Ekind (Index_Type)), N);
0669bebe 10183 Drange := Make_Range (Loc, New_Copy_Tree (Low_Bound), High_Bound);
c8ef728f
ES		 10184 Set_Scalar_Range (Index_Subtype, Drange);
10185 Set_Parent (Drange, N);
10186 Analyze_And_Resolve (Drange, Index_Type);
10187
36fcf362
RD		 10188 -- In the context, the Index_Type may already have a constraint,
10189 -- so use common base type on string subtype. The base type may
10190 -- be used when generating attributes of the string, for example
10191 -- in the context of a slice assignment.
10192
4adf3c50
AC		 10193 Set_Etype (Index_Subtype, Base_Type (Index_Type));
10194 Set_Size_Info (Index_Subtype, Index_Type);
10195 Set_RM_Size (Index_Subtype, RM_Size (Index_Type));
c8ef728f
ES		 10196
10197 Array_Subtype := Create_Itype (E_Array_Subtype, N);
10198
10199 Index := New_Occurrence_Of (Index_Subtype, Loc);
10200 Set_Etype (Index, Index_Subtype);
10201 Append (Index, Index_List);
10202
10203 Set_First_Index (Array_Subtype, Index);
10204 Set_Etype (Array_Subtype, Base_Type (Typ));
10205 Set_Is_Constrained (Array_Subtype, True);
c8ef728f
ES		 10206
10207 Rewrite (N,
10208 Make_Unchecked_Type_Conversion (Loc,
10209 Subtype_Mark => New_Occurrence_Of (Array_Subtype, Loc),
5f44f0d4 10210 Expression => Relocate_Node (N)));
c8ef728f
ES		 10211 Set_Etype (N, Array_Subtype);
10212 end;
10213 end if;
996ae0b0
RK		 10214 end Set_String_Literal_Subtype;
10215
0669bebe
GB		 10216 ------------------------------
10217 -- Simplify_Type_Conversion --
10218 ------------------------------
10219
10220 procedure Simplify_Type_Conversion (N : Node_Id) is
10221 begin
10222 if Nkind (N) = N_Type_Conversion then
10223 declare
10224 Operand : constant Node_Id := Expression (N);
10225 Target_Typ : constant Entity_Id := Etype (N);
10226 Opnd_Typ : constant Entity_Id := Etype (Operand);
10227
10228 begin
10229 if Is_Floating_Point_Type (Opnd_Typ)
10230 and then
10231 (Is_Integer_Type (Target_Typ)
10232 or else (Is_Fixed_Point_Type (Target_Typ)
10233 and then Conversion_OK (N)))
10234 and then Nkind (Operand) = N_Attribute_Reference
10235 and then Attribute_Name (Operand) = Name_Truncation
10236
10237 -- Special processing required if the conversion is the expression
10238 -- of a Truncation attribute reference. In this case we replace:
10239
10240 -- ityp (ftyp'Truncation (x))
10241
10242 -- by
10243
10244 -- ityp (x)
10245
4adf3c50 10246 -- with the Float_Truncate flag set, which is more efficient.
0669bebe
GB		 10247
10248 then
10249 Rewrite (Operand,
10250 Relocate_Node (First (Expressions (Operand))));
10251 Set_Float_Truncate (N, True);
10252 end if;
10253 end;
10254 end if;
10255 end Simplify_Type_Conversion;
10256
996ae0b0
RK		 10257 -----------------------------
10258 -- Unique_Fixed_Point_Type --
10259 -----------------------------
10260
10261 function Unique_Fixed_Point_Type (N : Node_Id) return Entity_Id is
10262 T1 : Entity_Id := Empty;
10263 T2 : Entity_Id;
10264 Item : Node_Id;
10265 Scop : Entity_Id;
10266
10267 procedure Fixed_Point_Error;
d81b4bfe
TQ		 10268 -- Give error messages for true ambiguity. Messages are posted on node
10269 -- N, and entities T1, T2 are the possible interpretations.
a77842bd
TQ		 10270
10271 -----------------------
10272 -- Fixed_Point_Error --
10273 -----------------------
996ae0b0
RK		 10274
10275 procedure Fixed_Point_Error is
10276 begin
ed2233dc
AC		 10277 Error_Msg_N ("ambiguous universal_fixed_expression", N);
10278 Error_Msg_NE ("\\possible interpretation as}", N, T1);
10279 Error_Msg_NE ("\\possible interpretation as}", N, T2);
996ae0b0
RK		 10280 end Fixed_Point_Error;
10281
a77842bd
TQ		 10282 -- Start of processing for Unique_Fixed_Point_Type
10283
996ae0b0
RK		 10284 begin
10285 -- The operations on Duration are visible, so Duration is always a
10286 -- possible interpretation.
10287
10288 T1 := Standard_Duration;
10289
bc5f3720 10290 -- Look for fixed-point types in enclosing scopes
996ae0b0 10291
fbf5a39b 10292 Scop := Current_Scope;
996ae0b0
RK		 10293 while Scop /= Standard_Standard loop
10294 T2 := First_Entity (Scop);
996ae0b0
RK		 10295 while Present (T2) loop
10296 if Is_Fixed_Point_Type (T2)
10297 and then Current_Entity (T2) = T2
10298 and then Scope (Base_Type (T2)) = Scop
10299 then
10300 if Present (T1) then
10301 Fixed_Point_Error;
10302 return Any_Type;
10303 else
10304 T1 := T2;
10305 end if;
10306 end if;
10307
10308 Next_Entity (T2);
10309 end loop;
10310
10311 Scop := Scope (Scop);
10312 end loop;
10313
a77842bd 10314 -- Look for visible fixed type declarations in the context
996ae0b0
RK		 10315
10316 Item := First (Context_Items (Cunit (Current_Sem_Unit)));
996ae0b0 10317 while Present (Item) loop
996ae0b0
RK		 10318 if Nkind (Item) = N_With_Clause then
10319 Scop := Entity (Name (Item));
10320 T2 := First_Entity (Scop);
996ae0b0
RK		 10321 while Present (T2) loop
10322 if Is_Fixed_Point_Type (T2)
10323 and then Scope (Base_Type (T2)) = Scop
19fb051c 10324 and then (Is_Potentially_Use_Visible (T2) or else In_Use (T2))
996ae0b0
RK		 10325 then
10326 if Present (T1) then
10327 Fixed_Point_Error;
10328 return Any_Type;
10329 else
10330 T1 := T2;
10331 end if;
10332 end if;
10333
10334 Next_Entity (T2);
10335 end loop;
10336 end if;
10337
10338 Next (Item);
10339 end loop;
10340
10341 if Nkind (N) = N_Real_Literal then
aa5147f0 10342 Error_Msg_NE ("?real literal interpreted as }!", N, T1);
996ae0b0 10343 else
aa5147f0 10344 Error_Msg_NE ("?universal_fixed expression interpreted as }!", N, T1);
996ae0b0
RK		 10345 end if;
10346
10347 return T1;
10348 end Unique_Fixed_Point_Type;
10349
10350 ----------------------
10351 -- Valid_Conversion --
10352 ----------------------
10353
10354 function Valid_Conversion
6cce2156
GD		 10355 (N : Node_Id;
10356 Target : Entity_Id;
10357 Operand : Node_Id;
10358 Report_Errs : Boolean := True) return Boolean
996ae0b0 10359 is
fbf5a39b 10360 Target_Type : constant Entity_Id := Base_Type (Target);
996c8821 10361 Opnd_Type : Entity_Id := Etype (Operand);
996ae0b0
RK		 10362
10363 function Conversion_Check
10364 (Valid : Boolean;
0ab80019 10365 Msg : String) return Boolean;
996ae0b0
RK		 10366 -- Little routine to post Msg if Valid is False, returns Valid value
10367
996c8821
RD		 10368 -- The following are badly named, this kind of overloading is actively
10369 -- confusing in reading code, please rename to something like
10370 -- Error_Msg_N_If_Reporting ???
10371
6cce2156
GD		 10372 procedure Error_Msg_N (Msg : String; N : Node_Or_Entity_Id);
10373 -- If Report_Errs, then calls Errout.Error_Msg_N with its arguments
10374
10375 procedure Error_Msg_NE
10376 (Msg : String;
10377 N : Node_Or_Entity_Id;
10378 E : Node_Or_Entity_Id);
10379 -- If Report_Errs, then calls Errout.Error_Msg_NE with its arguments
10380
996ae0b0
RK		 10381 function Valid_Tagged_Conversion
10382 (Target_Type : Entity_Id;
0ab80019 10383 Opnd_Type : Entity_Id) return Boolean;
996ae0b0
RK		 10384 -- Specifically test for validity of tagged conversions
10385
aa180613 10386 function Valid_Array_Conversion return Boolean;
4adf3c50
AC		 10387 -- Check index and component conformance, and accessibility levels if
10388 -- the component types are anonymous access types (Ada 2005).
aa180613 10389
996ae0b0
RK		 10390 ----------------------
10391 -- Conversion_Check --
10392 ----------------------
10393
10394 function Conversion_Check
10395 (Valid : Boolean;
0ab80019 10396 Msg : String) return Boolean
996ae0b0
RK		 10397 is
10398 begin
0a190dfd
AC		 10399 if not Valid
10400
10401 -- A generic unit has already been analyzed and we have verified
10402 -- that a particular conversion is OK in that context. Since the
10403 -- instance is reanalyzed without relying on the relationships
10404 -- established during the analysis of the generic, it is possible
10405 -- to end up with inconsistent views of private types. Do not emit
10406 -- the error message in such cases. The rest of the machinery in
10407 -- Valid_Conversion still ensures the proper compatibility of
10408 -- target and operand types.
10409
10410 and then not In_Instance
10411 then
996ae0b0
RK		 10412 Error_Msg_N (Msg, Operand);
10413 end if;
10414
10415 return Valid;
10416 end Conversion_Check;
10417
6cce2156
GD		 10418 -----------------
10419 -- Error_Msg_N --
10420 -----------------
10421
10422 procedure Error_Msg_N (Msg : String; N : Node_Or_Entity_Id) is
10423 begin
10424 if Report_Errs then
10425 Errout.Error_Msg_N (Msg, N);
10426 end if;
10427 end Error_Msg_N;
10428
10429 ------------------
10430 -- Error_Msg_NE --
10431 ------------------
10432
10433 procedure Error_Msg_NE
10434 (Msg : String;
10435 N : Node_Or_Entity_Id;
10436 E : Node_Or_Entity_Id)
10437 is
10438 begin
10439 if Report_Errs then
10440 Errout.Error_Msg_NE (Msg, N, E);
10441 end if;
10442 end Error_Msg_NE;
10443
aa180613
RD		 10444 ----------------------------
10445 -- Valid_Array_Conversion --
10446 ----------------------------
10447
10448 function Valid_Array_Conversion return Boolean
10449 is
10450 Opnd_Comp_Type : constant Entity_Id := Component_Type (Opnd_Type);
10451 Opnd_Comp_Base : constant Entity_Id := Base_Type (Opnd_Comp_Type);
10452
10453 Opnd_Index : Node_Id;
10454 Opnd_Index_Type : Entity_Id;
10455
10456 Target_Comp_Type : constant Entity_Id :=
10457 Component_Type (Target_Type);
10458 Target_Comp_Base : constant Entity_Id :=
10459 Base_Type (Target_Comp_Type);
10460
10461 Target_Index : Node_Id;
10462 Target_Index_Type : Entity_Id;
10463
10464 begin
10465 -- Error if wrong number of dimensions
10466
10467 if
10468 Number_Dimensions (Target_Type) /= Number_Dimensions (Opnd_Type)
10469 then
10470 Error_Msg_N
10471 ("incompatible number of dimensions for conversion", Operand);
10472 return False;
10473
10474 -- Number of dimensions matches
10475
10476 else
10477 -- Loop through indexes of the two arrays
10478
10479 Target_Index := First_Index (Target_Type);
10480 Opnd_Index := First_Index (Opnd_Type);
10481 while Present (Target_Index) and then Present (Opnd_Index) loop
10482 Target_Index_Type := Etype (Target_Index);
10483 Opnd_Index_Type := Etype (Opnd_Index);
10484
10485 -- Error if index types are incompatible
10486
10487 if not (Is_Integer_Type (Target_Index_Type)
10488 and then Is_Integer_Type (Opnd_Index_Type))
10489 and then (Root_Type (Target_Index_Type)
10490 /= Root_Type (Opnd_Index_Type))
10491 then
10492 Error_Msg_N
10493 ("incompatible index types for array conversion",
10494 Operand);
10495 return False;
10496 end if;
10497
10498 Next_Index (Target_Index);
10499 Next_Index (Opnd_Index);
10500 end loop;
10501
10502 -- If component types have same base type, all set
10503
10504 if Target_Comp_Base = Opnd_Comp_Base then
10505 null;
10506
10507 -- Here if base types of components are not the same. The only
10508 -- time this is allowed is if we have anonymous access types.
10509
10510 -- The conversion of arrays of anonymous access types can lead
10511 -- to dangling pointers. AI-392 formalizes the accessibility
10512 -- checks that must be applied to such conversions to prevent
10513 -- out-of-scope references.
10514
19fb051c
AC		 10515 elsif Ekind_In
10516 (Target_Comp_Base, E_Anonymous_Access_Type,
10517 E_Anonymous_Access_Subprogram_Type)
aa180613
RD		 10518 and then Ekind (Opnd_Comp_Base) = Ekind (Target_Comp_Base)
10519 and then
10520 Subtypes_Statically_Match (Target_Comp_Type, Opnd_Comp_Type)
10521 then
10522 if Type_Access_Level (Target_Type) <
83e5da69 10523 Deepest_Type_Access_Level (Opnd_Type)
aa180613
RD		 10524 then
10525 if In_Instance_Body then
83e5da69
AC		 10526 Error_Msg_N
10527 ("?source array type has " &
10528 "deeper accessibility level than target", Operand);
10529 Error_Msg_N
10530 ("\?Program_Error will be raised at run time",
10531 Operand);
aa180613
RD		 10532 Rewrite (N,
10533 Make_Raise_Program_Error (Sloc (N),
10534 Reason => PE_Accessibility_Check_Failed));
10535 Set_Etype (N, Target_Type);
10536 return False;
10537
10538 -- Conversion not allowed because of accessibility levels
10539
10540 else
83e5da69
AC		 10541 Error_Msg_N
10542 ("source array type has " &
10543 "deeper accessibility level than target", Operand);
aa180613
RD		 10544 return False;
10545 end if;
19fb051c 10546
aa180613
RD		 10547 else
10548 null;
10549 end if;
10550
10551 -- All other cases where component base types do not match
10552
10553 else
10554 Error_Msg_N
10555 ("incompatible component types for array conversion",
10556 Operand);
10557 return False;
10558 end if;
10559
45fc7ddb
HK		 10560 -- Check that component subtypes statically match. For numeric
10561 -- types this means that both must be either constrained or
10562 -- unconstrained. For enumeration types the bounds must match.
10563 -- All of this is checked in Subtypes_Statically_Match.
aa180613 10564
45fc7ddb 10565 if not Subtypes_Statically_Match
83e5da69 10566 (Target_Comp_Type, Opnd_Comp_Type)
aa180613
RD		 10567 then
10568 Error_Msg_N
10569 ("component subtypes must statically match", Operand);
10570 return False;
10571 end if;
10572 end if;
10573
10574 return True;
10575 end Valid_Array_Conversion;
10576
996ae0b0
RK		 10577 -----------------------------
10578 -- Valid_Tagged_Conversion --
10579 -----------------------------
10580
10581 function Valid_Tagged_Conversion
10582 (Target_Type : Entity_Id;
0ab80019 10583 Opnd_Type : Entity_Id) return Boolean
996ae0b0
RK		 10584 is
10585 begin
a77842bd 10586 -- Upward conversions are allowed (RM 4.6(22))
996ae0b0
RK		 10587
10588 if Covers (Target_Type, Opnd_Type)
10589 or else Is_Ancestor (Target_Type, Opnd_Type)
10590 then
10591 return True;
10592
a77842bd
TQ		 10593 -- Downward conversion are allowed if the operand is class-wide
10594 -- (RM 4.6(23)).
996ae0b0
RK		 10595
10596 elsif Is_Class_Wide_Type (Opnd_Type)
b7d1f17f 10597 and then Covers (Opnd_Type, Target_Type)
996ae0b0
RK		 10598 then
10599 return True;
10600
10601 elsif Covers (Opnd_Type, Target_Type)
10602 or else Is_Ancestor (Opnd_Type, Target_Type)
10603 then
10604 return
10605 Conversion_Check (False,
10606 "downward conversion of tagged objects not allowed");
758c442c 10607
0669bebe
GB		 10608 -- Ada 2005 (AI-251): The conversion to/from interface types is
10609 -- always valid
758c442c 10610
0669bebe 10611 elsif Is_Interface (Target_Type) or else Is_Interface (Opnd_Type) then
758c442c
GD		 10612 return True;
10613
b7d1f17f
HK		 10614 -- If the operand is a class-wide type obtained through a limited_
10615 -- with clause, and the context includes the non-limited view, use
10616 -- it to determine whether the conversion is legal.
10617
10618 elsif Is_Class_Wide_Type (Opnd_Type)
10619 and then From_With_Type (Opnd_Type)
10620 and then Present (Non_Limited_View (Etype (Opnd_Type)))
10621 and then Is_Interface (Non_Limited_View (Etype (Opnd_Type)))
10622 then
10623 return True;
10624
aa180613
RD		 10625 elsif Is_Access_Type (Opnd_Type)
10626 and then Is_Interface (Directly_Designated_Type (Opnd_Type))
10627 then
10628 return True;
10629
996ae0b0
RK		 10630 else
10631 Error_Msg_NE
10632 ("invalid tagged conversion, not compatible with}",
10633 N, First_Subtype (Opnd_Type));
10634 return False;
10635 end if;
10636 end Valid_Tagged_Conversion;
10637
10638 -- Start of processing for Valid_Conversion
10639
10640 begin
10641 Check_Parameterless_Call (Operand);
10642
10643 if Is_Overloaded (Operand) then
10644 declare
10645 I : Interp_Index;
10646 I1 : Interp_Index;
10647 It : Interp;
10648 It1 : Interp;
10649 N1 : Entity_Id;
f0d10385 10650 T1 : Entity_Id;
996ae0b0
RK		 10651
10652 begin
d81b4bfe
TQ		 10653 -- Remove procedure calls, which syntactically cannot appear in
10654 -- this context, but which cannot be removed by type checking,
996ae0b0
RK		 10655 -- because the context does not impose a type.
10656
1420b484
JM		 10657 -- When compiling for VMS, spurious ambiguities can be produced
10658 -- when arithmetic operations have a literal operand and return
10659 -- System.Address or a descendant of it. These ambiguities are
10660 -- otherwise resolved by the context, but for conversions there
10661 -- is no context type and the removal of the spurious operations
10662 -- must be done explicitly here.
10663
4adf3c50
AC		 10664 -- The node may be labelled overloaded, but still contain only one
10665 -- interpretation because others were discarded earlier. If this
10666 -- is the case, retain the single interpretation if legal.
9ebe3743 10667
996ae0b0 10668 Get_First_Interp (Operand, I, It);
9ebe3743
HK		 10669 Opnd_Type := It.Typ;
10670 Get_Next_Interp (I, It);
996ae0b0 10671
9ebe3743
HK		 10672 if Present (It.Typ)
10673 and then Opnd_Type /= Standard_Void_Type
10674 then
10675 -- More than one candidate interpretation is available
996ae0b0 10676
9ebe3743
HK		 10677 Get_First_Interp (Operand, I, It);
10678 while Present (It.Typ) loop
10679 if It.Typ = Standard_Void_Type then
10680 Remove_Interp (I);
10681 end if;
1420b484 10682
9ebe3743
HK		 10683 if Present (System_Aux_Id)
10684 and then Is_Descendent_Of_Address (It.Typ)
10685 then
10686 Remove_Interp (I);
10687 end if;
10688
10689 Get_Next_Interp (I, It);
10690 end loop;
10691 end if;
996ae0b0
RK		 10692
10693 Get_First_Interp (Operand, I, It);
10694 I1 := I;
10695 It1 := It;
10696
10697 if No (It.Typ) then
10698 Error_Msg_N ("illegal operand in conversion", Operand);
10699 return False;
10700 end if;
10701
10702 Get_Next_Interp (I, It);
10703
10704 if Present (It.Typ) then
10705 N1 := It1.Nam;
f0d10385 10706 T1 := It1.Typ;
996ae0b0
RK		 10707 It1 := Disambiguate (Operand, I1, I, Any_Type);
10708
10709 if It1 = No_Interp then
10710 Error_Msg_N ("ambiguous operand in conversion", Operand);
10711
f0d10385
AC		 10712 -- If the interpretation involves a standard operator, use
10713 -- the location of the type, which may be user-defined.
10714
10715 if Sloc (It.Nam) = Standard_Location then
10716 Error_Msg_Sloc := Sloc (It.Typ);
10717 else
10718 Error_Msg_Sloc := Sloc (It.Nam);
10719 end if;
10720
4e7a4f6e
AC		 10721 Error_Msg_N -- CODEFIX
10722 ("\\possible interpretation#!", Operand);
996ae0b0 10723
f0d10385
AC		 10724 if Sloc (N1) = Standard_Location then
10725 Error_Msg_Sloc := Sloc (T1);
10726 else
10727 Error_Msg_Sloc := Sloc (N1);
10728 end if;
10729
4e7a4f6e
AC		 10730 Error_Msg_N -- CODEFIX
10731 ("\\possible interpretation#!", Operand);
996ae0b0
RK		 10732
10733 return False;
10734 end if;
10735 end if;
10736
10737 Set_Etype (Operand, It1.Typ);
10738 Opnd_Type := It1.Typ;
10739 end;
10740 end if;
10741
aa180613 10742 -- Numeric types
996ae0b0 10743
aa180613 10744 if Is_Numeric_Type (Target_Type) then
996ae0b0 10745
aa180613 10746 -- A universal fixed expression can be converted to any numeric type
996ae0b0 10747
996ae0b0
RK		 10748 if Opnd_Type = Universal_Fixed then
10749 return True;
7324bf49 10750
aa180613
RD		 10751 -- Also no need to check when in an instance or inlined body, because
10752 -- the legality has been established when the template was analyzed.
10753 -- Furthermore, numeric conversions may occur where only a private
f3d57416 10754 -- view of the operand type is visible at the instantiation point.
aa180613
RD		 10755 -- This results in a spurious error if we check that the operand type
10756 -- is a numeric type.
10757
10758 -- Note: in a previous version of this unit, the following tests were
10759 -- applied only for generated code (Comes_From_Source set to False),
10760 -- but in fact the test is required for source code as well, since
10761 -- this situation can arise in source code.
10762
10763 elsif In_Instance or else In_Inlined_Body then
d347f572 10764 return True;
aa180613
RD		 10765
10766 -- Otherwise we need the conversion check
7324bf49 10767
996ae0b0 10768 else
aa180613
RD		 10769 return Conversion_Check
10770 (Is_Numeric_Type (Opnd_Type),
10771 "illegal operand for numeric conversion");
996ae0b0
RK		 10772 end if;
10773
aa180613
RD		 10774 -- Array types
10775
996ae0b0
RK		 10776 elsif Is_Array_Type (Target_Type) then
10777 if not Is_Array_Type (Opnd_Type)
10778 or else Opnd_Type = Any_Composite
10779 or else Opnd_Type = Any_String
10780 then
4adf3c50 10781 Error_Msg_N ("illegal operand for array conversion", Operand);
996ae0b0 10782 return False;
996ae0b0 10783 else
aa180613 10784 return Valid_Array_Conversion;
996ae0b0
RK		 10785 end if;
10786
e65f50ec
ES		 10787 -- Ada 2005 (AI-251): Anonymous access types where target references an
10788 -- interface type.
758c442c 10789
964f13da
RD		 10790 elsif Ekind_In (Target_Type, E_General_Access_Type,
10791 E_Anonymous_Access_Type)
758c442c
GD		 10792 and then Is_Interface (Directly_Designated_Type (Target_Type))
10793 then
10794 -- Check the static accessibility rule of 4.6(17). Note that the
d81b4bfe
TQ		 10795 -- check is not enforced when within an instance body, since the
10796 -- RM requires such cases to be caught at run time.
758c442c 10797
4172a8e3
AC		 10798 -- If the operand is a rewriting of an allocator no check is needed
10799 -- because there are no accessibility issues.
10800
10801 if Nkind (Original_Node (N)) = N_Allocator then
10802 null;
10803
10804 elsif Ekind (Target_Type) /= E_Anonymous_Access_Type then
758c442c 10805 if Type_Access_Level (Opnd_Type) >
996c8821 10806 Deepest_Type_Access_Level (Target_Type)
758c442c
GD		 10807 then
10808 -- In an instance, this is a run-time check, but one we know
10809 -- will fail, so generate an appropriate warning. The raise
10810 -- will be generated by Expand_N_Type_Conversion.
10811
10812 if In_Instance_Body then
10813 Error_Msg_N
10814 ("?cannot convert local pointer to non-local access type",
10815 Operand);
10816 Error_Msg_N
c8ef728f 10817 ("\?Program_Error will be raised at run time", Operand);
996c8821 10818
758c442c
GD		 10819 else
10820 Error_Msg_N
10821 ("cannot convert local pointer to non-local access type",
10822 Operand);
10823 return False;
10824 end if;
10825
10826 -- Special accessibility checks are needed in the case of access
10827 -- discriminants declared for a limited type.
10828
10829 elsif Ekind (Opnd_Type) = E_Anonymous_Access_Type
10830 and then not Is_Local_Anonymous_Access (Opnd_Type)
10831 then
10832 -- When the operand is a selected access discriminant the check
10833 -- needs to be made against the level of the object denoted by
d81b4bfe
TQ		 10834 -- the prefix of the selected name (Object_Access_Level handles
10835 -- checking the prefix of the operand for this case).
758c442c
GD		 10836
10837 if Nkind (Operand) = N_Selected_Component
c8ef728f 10838 and then Object_Access_Level (Operand) >
d15f9422 10839 Deepest_Type_Access_Level (Target_Type)
758c442c 10840 then
d81b4bfe
TQ		 10841 -- In an instance, this is a run-time check, but one we know
10842 -- will fail, so generate an appropriate warning. The raise
10843 -- will be generated by Expand_N_Type_Conversion.
758c442c
GD		 10844
10845 if In_Instance_Body then
10846 Error_Msg_N
10847 ("?cannot convert access discriminant to non-local" &
10848 " access type", Operand);
10849 Error_Msg_N
c8ef728f 10850 ("\?Program_Error will be raised at run time", Operand);
758c442c
GD		 10851 else
10852 Error_Msg_N
10853 ("cannot convert access discriminant to non-local" &
10854 " access type", Operand);
10855 return False;
10856 end if;
10857 end if;
10858
10859 -- The case of a reference to an access discriminant from
10860 -- within a limited type declaration (which will appear as
10861 -- a discriminal) is always illegal because the level of the
f3d57416 10862 -- discriminant is considered to be deeper than any (nameable)
758c442c
GD		 10863 -- access type.
10864
10865 if Is_Entity_Name (Operand)
10866 and then not Is_Local_Anonymous_Access (Opnd_Type)
964f13da
RD		 10867 and then
10868 Ekind_In (Entity (Operand), E_In_Parameter, E_Constant)
758c442c
GD		 10869 and then Present (Discriminal_Link (Entity (Operand)))
10870 then
10871 Error_Msg_N
10872 ("discriminant has deeper accessibility level than target",
10873 Operand);
10874 return False;
10875 end if;
10876 end if;
10877 end if;
10878
10879 return True;
10880
aa180613
RD		 10881 -- General and anonymous access types
10882
964f13da
RD		 10883 elsif Ekind_In (Target_Type, E_General_Access_Type,
10884 E_Anonymous_Access_Type)
996ae0b0
RK		 10885 and then
10886 Conversion_Check
10887 (Is_Access_Type (Opnd_Type)
964f13da
RD		 10888 and then not
10889 Ekind_In (Opnd_Type, E_Access_Subprogram_Type,
10890 E_Access_Protected_Subprogram_Type),
996ae0b0
RK		 10891 "must be an access-to-object type")
10892 then
10893 if Is_Access_Constant (Opnd_Type)
10894 and then not Is_Access_Constant (Target_Type)
10895 then
10896 Error_Msg_N
10897 ("access-to-constant operand type not allowed", Operand);
10898 return False;
10899 end if;
10900
758c442c
GD		 10901 -- Check the static accessibility rule of 4.6(17). Note that the
10902 -- check is not enforced when within an instance body, since the RM
10903 -- requires such cases to be caught at run time.
996ae0b0 10904
758c442c
GD		 10905 if Ekind (Target_Type) /= E_Anonymous_Access_Type
10906 or else Is_Local_Anonymous_Access (Target_Type)
d15f9422 10907 or else Nkind (Associated_Node_For_Itype (Target_Type)) =
996c8821 10908 N_Object_Declaration
758c442c 10909 then
6cce2156
GD		 10910 -- Ada 2012 (AI05-0149): Perform legality checking on implicit
10911 -- conversions from an anonymous access type to a named general
10912 -- access type. Such conversions are not allowed in the case of
10913 -- access parameters and stand-alone objects of an anonymous
c199ccf7
AC		 10914 -- access type. The implicit conversion case is recognized by
10915 -- testing that Comes_From_Source is False and that it's been
10916 -- rewritten. The Comes_From_Source test isn't sufficient because
10917 -- nodes in inlined calls to predefined library routines can have
10918 -- Comes_From_Source set to False. (Is there a better way to test
10919 -- for implicit conversions???)
6cce2156
GD		 10920
10921 if Ada_Version >= Ada_2012
10922 and then not Comes_From_Source (N)
c199ccf7 10923 and then N /= Original_Node (N)
6cce2156
GD		 10924 and then Ekind (Target_Type) = E_General_Access_Type
10925 and then Ekind (Opnd_Type) = E_Anonymous_Access_Type
996ae0b0 10926 then
6cce2156
GD		 10927 if Is_Itype (Opnd_Type) then
10928
10929 -- Implicit conversions aren't allowed for objects of an
10930 -- anonymous access type, since such objects have nonstatic
10931 -- levels in Ada 2012.
10932
10933 if Nkind (Associated_Node_For_Itype (Opnd_Type)) =
10934 N_Object_Declaration
10935 then
10936 Error_Msg_N
10937 ("implicit conversion of stand-alone anonymous " &
10938 "access object not allowed", Operand);
10939 return False;
10940
10941 -- Implicit conversions aren't allowed for anonymous access
10942 -- parameters. The "not Is_Local_Anonymous_Access_Type" test
10943 -- is done to exclude anonymous access results.
10944
10945 elsif not Is_Local_Anonymous_Access (Opnd_Type)
10946 and then Nkind_In (Associated_Node_For_Itype (Opnd_Type),
10947 N_Function_Specification,
10948 N_Procedure_Specification)
10949 then
10950 Error_Msg_N
10951 ("implicit conversion of anonymous access formal " &
10952 "not allowed", Operand);
10953 return False;
10954
10955 -- This is a case where there's an enclosing object whose
10956 -- to which the "statically deeper than" relationship does
10957 -- not apply (such as an access discriminant selected from
10958 -- a dereference of an access parameter).
10959
10960 elsif Object_Access_Level (Operand)
10961 = Scope_Depth (Standard_Standard)
10962 then
10963 Error_Msg_N
10964 ("implicit conversion of anonymous access value " &
10965 "not allowed", Operand);
10966 return False;
10967
10968 -- In other cases, the level of the operand's type must be
10969 -- statically less deep than that of the target type, else
10970 -- implicit conversion is disallowed (by RM12-8.6(27.1/3)).
10971
d15f9422 10972 elsif Type_Access_Level (Opnd_Type) >
996c8821 10973 Deepest_Type_Access_Level (Target_Type)
6cce2156
GD		 10974 then
10975 Error_Msg_N
10976 ("implicit conversion of anonymous access value " &
10977 "violates accessibility", Operand);
10978 return False;
10979 end if;
10980 end if;
10981
d15f9422 10982 elsif Type_Access_Level (Opnd_Type) >
996c8821 10983 Deepest_Type_Access_Level (Target_Type)
6cce2156 10984 then
d81b4bfe
TQ		 10985 -- In an instance, this is a run-time check, but one we know
10986 -- will fail, so generate an appropriate warning. The raise
10987 -- will be generated by Expand_N_Type_Conversion.
996ae0b0
RK		 10988
10989 if In_Instance_Body then
10990 Error_Msg_N
10991 ("?cannot convert local pointer to non-local access type",
10992 Operand);
10993 Error_Msg_N
c8ef728f 10994 ("\?Program_Error will be raised at run time", Operand);
996ae0b0
RK		 10995
10996 else
b90cfacd
HK		 10997 -- Avoid generation of spurious error message
10998
10999 if not Error_Posted (N) then
11000 Error_Msg_N
11001 ("cannot convert local pointer to non-local access type",
11002 Operand);
11003 end if;
11004
996ae0b0
RK		 11005 return False;
11006 end if;
11007
758c442c
GD		 11008 -- Special accessibility checks are needed in the case of access
11009 -- discriminants declared for a limited type.
11010
11011 elsif Ekind (Opnd_Type) = E_Anonymous_Access_Type
11012 and then not Is_Local_Anonymous_Access (Opnd_Type)
11013 then
758c442c
GD		 11014 -- When the operand is a selected access discriminant the check
11015 -- needs to be made against the level of the object denoted by
d81b4bfe
TQ		 11016 -- the prefix of the selected name (Object_Access_Level handles
11017 -- checking the prefix of the operand for this case).
996ae0b0
RK		 11018
11019 if Nkind (Operand) = N_Selected_Component
45fc7ddb 11020 and then Object_Access_Level (Operand) >
996c8821 11021 Deepest_Type_Access_Level (Target_Type)
996ae0b0 11022 then
d81b4bfe
TQ		 11023 -- In an instance, this is a run-time check, but one we know
11024 -- will fail, so generate an appropriate warning. The raise
11025 -- will be generated by Expand_N_Type_Conversion.
996ae0b0
RK		 11026
11027 if In_Instance_Body then
11028 Error_Msg_N
11029 ("?cannot convert access discriminant to non-local" &
11030 " access type", Operand);
11031 Error_Msg_N
c8ef728f
ES		 11032 ("\?Program_Error will be raised at run time",
11033 Operand);
996ae0b0
RK		 11034
11035 else
11036 Error_Msg_N
11037 ("cannot convert access discriminant to non-local" &
11038 " access type", Operand);
11039 return False;
11040 end if;
11041 end if;
11042
758c442c
GD		 11043 -- The case of a reference to an access discriminant from
11044 -- within a limited type declaration (which will appear as
11045 -- a discriminal) is always illegal because the level of the
f3d57416 11046 -- discriminant is considered to be deeper than any (nameable)
758c442c 11047 -- access type.
996ae0b0
RK		 11048
11049 if Is_Entity_Name (Operand)
964f13da
RD		 11050 and then
11051 Ekind_In (Entity (Operand), E_In_Parameter, E_Constant)
996ae0b0
RK		 11052 and then Present (Discriminal_Link (Entity (Operand)))
11053 then
11054 Error_Msg_N
11055 ("discriminant has deeper accessibility level than target",
11056 Operand);
11057 return False;
11058 end if;
11059 end if;
11060 end if;
11061
14e33999
AC		 11062 -- In the presence of limited_with clauses we have to use non-limited
11063 -- views, if available.
d81b4bfe 11064
14e33999 11065 Check_Limited : declare
0669bebe
GB		 11066 function Full_Designated_Type (T : Entity_Id) return Entity_Id;
11067 -- Helper function to handle limited views
11068
11069 --------------------------
11070 -- Full_Designated_Type --
11071 --------------------------
11072
11073 function Full_Designated_Type (T : Entity_Id) return Entity_Id is
950d217a 11074 Desig : constant Entity_Id := Designated_Type (T);
c0985d4e 11075
0669bebe 11076 begin
950d217a
AC		 11077 -- Handle the limited view of a type
11078
c0985d4e
HK		 11079 if Is_Incomplete_Type (Desig)
11080 and then From_With_Type (Desig)
0669bebe
GB		 11081 and then Present (Non_Limited_View (Desig))
11082 then
950d217a
AC		 11083 return Available_View (Desig);
11084 else
11085 return Desig;
0669bebe
GB		 11086 end if;
11087 end Full_Designated_Type;
11088
d81b4bfe
TQ		 11089 -- Local Declarations
11090
0669bebe
GB		 11091 Target : constant Entity_Id := Full_Designated_Type (Target_Type);
11092 Opnd : constant Entity_Id := Full_Designated_Type (Opnd_Type);
11093
11094 Same_Base : constant Boolean :=
11095 Base_Type (Target) = Base_Type (Opnd);
996ae0b0 11096
14e33999 11097 -- Start of processing for Check_Limited
d81b4bfe 11098
996ae0b0
RK		 11099 begin
11100 if Is_Tagged_Type (Target) then
11101 return Valid_Tagged_Conversion (Target, Opnd);
11102
11103 else
0669bebe 11104 if not Same_Base then
996ae0b0
RK		 11105 Error_Msg_NE
11106 ("target designated type not compatible with }",
11107 N, Base_Type (Opnd));
11108 return False;
11109
da709d08
AC		 11110 -- Ada 2005 AI-384: legality rule is symmetric in both
11111 -- designated types. The conversion is legal (with possible
11112 -- constraint check) if either designated type is
11113 -- unconstrained.
11114
11115 elsif Subtypes_Statically_Match (Target, Opnd)
11116 or else
11117 (Has_Discriminants (Target)
11118 and then
11119 (not Is_Constrained (Opnd)
11120 or else not Is_Constrained (Target)))
996ae0b0 11121 then
9fa33291
RD		 11122 -- Special case, if Value_Size has been used to make the
11123 -- sizes different, the conversion is not allowed even
11124 -- though the subtypes statically match.
11125
11126 if Known_Static_RM_Size (Target)
11127 and then Known_Static_RM_Size (Opnd)
11128 and then RM_Size (Target) /= RM_Size (Opnd)
11129 then
11130 Error_Msg_NE
11131 ("target designated subtype not compatible with }",
11132 N, Opnd);
11133 Error_Msg_NE
11134 ("\because sizes of the two designated subtypes differ",
11135 N, Opnd);
11136 return False;
11137
11138 -- Normal case where conversion is allowed
11139
11140 else
11141 return True;
11142 end if;
da709d08
AC		 11143
11144 else
996ae0b0
RK		 11145 Error_Msg_NE
11146 ("target designated subtype not compatible with }",
11147 N, Opnd);
11148 return False;
996ae0b0
RK		 11149 end if;
11150 end if;
14e33999 11151 end Check_Limited;
996ae0b0 11152
cdbf04c0 11153 -- Access to subprogram types. If the operand is an access parameter,
4adf3c50
AC		 11154 -- the type has a deeper accessibility that any master, and cannot be
11155 -- assigned. We must make an exception if the conversion is part of an
11156 -- assignment and the target is the return object of an extended return
11157 -- statement, because in that case the accessibility check takes place
11158 -- after the return.
aa180613 11159
dce86910 11160 elsif Is_Access_Subprogram_Type (Target_Type)
bc5f3720 11161 and then No (Corresponding_Remote_Type (Opnd_Type))
996ae0b0 11162 then
cdbf04c0
AC		 11163 if Ekind (Base_Type (Opnd_Type)) = E_Anonymous_Access_Subprogram_Type
11164 and then Is_Entity_Name (Operand)
11165 and then Ekind (Entity (Operand)) = E_In_Parameter
53cf4600
ES		 11166 and then
11167 (Nkind (Parent (N)) /= N_Assignment_Statement
11168 or else not Is_Entity_Name (Name (Parent (N)))
11169 or else not Is_Return_Object (Entity (Name (Parent (N)))))
0669bebe
GB		 11170 then
11171 Error_Msg_N
11172 ("illegal attempt to store anonymous access to subprogram",
11173 Operand);
11174 Error_Msg_N
11175 ("\value has deeper accessibility than any master " &
aa5147f0 11176 "(RM 3.10.2 (13))",
0669bebe
GB		 11177 Operand);
11178
c147ac26
ES		 11179 Error_Msg_NE
11180 ("\use named access type for& instead of access parameter",
11181 Operand, Entity (Operand));
0669bebe
GB		 11182 end if;
11183
996ae0b0
RK		 11184 -- Check that the designated types are subtype conformant
11185
bc5f3720
RD		 11186 Check_Subtype_Conformant (New_Id => Designated_Type (Target_Type),
11187 Old_Id => Designated_Type (Opnd_Type),
11188 Err_Loc => N);
996ae0b0
RK		 11189
11190 -- Check the static accessibility rule of 4.6(20)
11191
11192 if Type_Access_Level (Opnd_Type) >
996c8821 11193 Deepest_Type_Access_Level (Target_Type)
996ae0b0
RK		 11194 then
11195 Error_Msg_N
11196 ("operand type has deeper accessibility level than target",
11197 Operand);
11198
11199 -- Check that if the operand type is declared in a generic body,
11200 -- then the target type must be declared within that same body
11201 -- (enforces last sentence of 4.6(20)).
11202
11203 elsif Present (Enclosing_Generic_Body (Opnd_Type)) then
11204 declare
11205 O_Gen : constant Node_Id :=
11206 Enclosing_Generic_Body (Opnd_Type);
11207
1420b484 11208 T_Gen : Node_Id;
996ae0b0
RK		 11209
11210 begin
1420b484 11211 T_Gen := Enclosing_Generic_Body (Target_Type);
996ae0b0
RK		 11212 while Present (T_Gen) and then T_Gen /= O_Gen loop
11213 T_Gen := Enclosing_Generic_Body (T_Gen);
11214 end loop;
11215
11216 if T_Gen /= O_Gen then
11217 Error_Msg_N
11218 ("target type must be declared in same generic body"
11219 & " as operand type", N);
11220 end if;
11221 end;
11222 end if;
11223
11224 return True;
11225
aa180613
RD		 11226 -- Remote subprogram access types
11227
996ae0b0
RK		 11228 elsif Is_Remote_Access_To_Subprogram_Type (Target_Type)
11229 and then Is_Remote_Access_To_Subprogram_Type (Opnd_Type)
11230 then
11231 -- It is valid to convert from one RAS type to another provided
11232 -- that their specification statically match.
11233
11234 Check_Subtype_Conformant
11235 (New_Id =>
11236 Designated_Type (Corresponding_Remote_Type (Target_Type)),
11237 Old_Id =>
11238 Designated_Type (Corresponding_Remote_Type (Opnd_Type)),
11239 Err_Loc =>
11240 N);
11241 return True;
aa180613 11242
be482a8c
AC		 11243 -- If it was legal in the generic, it's legal in the instance
11244
11245 elsif In_Instance_Body then
11246 return True;
11247
e65f50ec 11248 -- If both are tagged types, check legality of view conversions
996ae0b0 11249
e65f50ec 11250 elsif Is_Tagged_Type (Target_Type)
4adf3c50
AC		 11251 and then
11252 Is_Tagged_Type (Opnd_Type)
e65f50ec 11253 then
996ae0b0
RK		 11254 return Valid_Tagged_Conversion (Target_Type, Opnd_Type);
11255
a77842bd 11256 -- Types derived from the same root type are convertible
996ae0b0
RK		 11257
11258 elsif Root_Type (Target_Type) = Root_Type (Opnd_Type) then
11259 return True;
11260
4adf3c50
AC		 11261 -- In an instance or an inlined body, there may be inconsistent views of
11262 -- the same type, or of types derived from a common root.
996ae0b0 11263
aa5147f0
ES		 11264 elsif (In_Instance or In_Inlined_Body)
11265 and then
d81b4bfe
TQ		 11266 Root_Type (Underlying_Type (Target_Type)) =
11267 Root_Type (Underlying_Type (Opnd_Type))
996ae0b0
RK		 11268 then
11269 return True;
11270
11271 -- Special check for common access type error case
11272
11273 elsif Ekind (Target_Type) = E_Access_Type
11274 and then Is_Access_Type (Opnd_Type)
11275 then
11276 Error_Msg_N ("target type must be general access type!", N);
305caf42
AC		 11277 Error_Msg_NE -- CODEFIX
11278 ("add ALL to }!", N, Target_Type);
996ae0b0
RK		 11279 return False;
11280
11281 else
11282 Error_Msg_NE ("invalid conversion, not compatible with }",
11283 N, Opnd_Type);
996ae0b0
RK		 11284 return False;
11285 end if;
11286 end Valid_Conversion;
11287
11288end Sem_Res;
GNU Compiler Collection
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