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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-- --
7a71a7c4 9-- Copyright (C) 1992-2017, 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 39with Freeze; use Freeze;
8636f52f 40with Ghost; use Ghost;
ecad37f3 41with Inline; use Inline;
996ae0b0
RK		 42with Itypes; use Itypes;
43with Lib; use Lib;
44with Lib.Xref; use Lib.Xref;
45with Namet; use Namet;
46with Nmake; use Nmake;
47with Nlists; use Nlists;
48with Opt; use Opt;
49with Output; use Output;
0566484a 50with Par_SCO; use Par_SCO;
996ae0b0 51with Restrict; use Restrict;
6e937c1c 52with Rident; use Rident;
996ae0b0
RK		 53with Rtsfind; use Rtsfind;
54with Sem; use Sem;
a4100e55 55with Sem_Aux; use Sem_Aux;
996ae0b0
RK		 56with Sem_Aggr; use Sem_Aggr;
57with Sem_Attr; use Sem_Attr;
58with Sem_Cat; use Sem_Cat;
59with Sem_Ch4; use Sem_Ch4;
7f54dc83 60with Sem_Ch3; use Sem_Ch3;
996ae0b0
RK		 61with Sem_Ch6; use Sem_Ch6;
62with Sem_Ch8; use Sem_Ch8;
4b92fd3c 63with Sem_Ch13; use Sem_Ch13;
dec6faf1 64with Sem_Dim; use Sem_Dim;
996ae0b0
RK		 65with Sem_Disp; use Sem_Disp;
66with Sem_Dist; use Sem_Dist;
16212e89 67with Sem_Elim; use Sem_Elim;
996ae0b0
RK		 68with Sem_Elab; use Sem_Elab;
69with Sem_Eval; use Sem_Eval;
70with Sem_Intr; use Sem_Intr;
71with Sem_Util; use Sem_Util;
ce72a9a3 72with Targparm; use Targparm;
996ae0b0
RK		 73with Sem_Type; use Sem_Type;
74with Sem_Warn; use Sem_Warn;
75with Sinfo; use Sinfo;
f4b049db 76with Sinfo.CN; use Sinfo.CN;
fbf5a39b 77with Snames; use Snames;
996ae0b0
RK		 78with Stand; use Stand;
79with Stringt; use Stringt;
45fc7ddb 80with Style; use Style;
996ae0b0
RK		 81with Tbuild; use Tbuild;
82with Uintp; use Uintp;
83with Urealp; use Urealp;
84
85package body Sem_Res is
86
87 -----------------------
88 -- Local Subprograms --
89 -----------------------
90
91 -- Second pass (top-down) type checking and overload resolution procedures
ac16e74c
RD		 92 -- Typ is the type required by context. These procedures propagate the
93 -- type information recursively to the descendants of N. If the node is not
5cc9353d 94 -- overloaded, its Etype is established in the first pass. If overloaded,
ac16e74c 95 -- the Resolve routines set the correct type. For arithmetic operators, the
5cc9353d 96 -- Etype is the base type of the context.
996ae0b0
RK		 97
98 -- Note that Resolve_Attribute is separated off in Sem_Attr
99
996ae0b0
RK		 100 procedure Check_Discriminant_Use (N : Node_Id);
101 -- Enforce the restrictions on the use of discriminants when constraining
102 -- a component of a discriminated type (record or concurrent type).
103
104 procedure Check_For_Visible_Operator (N : Node_Id; T : Entity_Id);
966fc9c5
AC		 105 -- Given a node for an operator associated with type T, check that the
106 -- operator is visible. Operators all of whose operands are universal must
107 -- be checked for visibility during resolution because their type is not
108 -- determinable based on their operands.
996ae0b0 109
c8ef728f
ES		 110 procedure Check_Fully_Declared_Prefix
111 (Typ : Entity_Id;
112 Pref : Node_Id);
113 -- Check that the type of the prefix of a dereference is not incomplete
114
996ae0b0
RK		 115 function Check_Infinite_Recursion (N : Node_Id) return Boolean;
116 -- Given a call node, N, which is known to occur immediately within the
117 -- subprogram being called, determines whether it is a detectable case of
118 -- an infinite recursion, and if so, outputs appropriate messages. Returns
119 -- True if an infinite recursion is detected, and False otherwise.
120
121 procedure Check_Initialization_Call (N : Entity_Id; Nam : Entity_Id);
122 -- If the type of the object being initialized uses the secondary stack
123 -- directly or indirectly, create a transient scope for the call to the
fbf5a39b
AC		 124 -- init proc. This is because we do not create transient scopes for the
125 -- initialization of individual components within the init proc itself.
996ae0b0
RK		 126 -- Could be optimized away perhaps?
127
f61580d4 128 procedure Check_No_Direct_Boolean_Operators (N : Node_Id);
6fb4cdde
AC		 129 -- N is the node for a logical operator. If the operator is predefined, and
130 -- the root type of the operands is Standard.Boolean, then a check is made
a36c1c3e
RD		 131 -- for restriction No_Direct_Boolean_Operators. This procedure also handles
132 -- the style check for Style_Check_Boolean_And_Or.
f61580d4 133
c2a2dbcc
RD		 134 function Is_Atomic_Ref_With_Address (N : Node_Id) return Boolean;
135 -- N is either an indexed component or a selected component. This function
136 -- returns true if the prefix refers to an object that has an address
137 -- clause (the case in which we may want to issue a warning).
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);
955871d3 181 procedure Resolve_Entity_Name (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 182 procedure Resolve_Equality_Op (N : Node_Id; Typ : Entity_Id);
183 procedure Resolve_Explicit_Dereference (N : Node_Id; Typ : Entity_Id);
955871d3 184 procedure Resolve_Expression_With_Actions (N : Node_Id; Typ : Entity_Id);
9b16cb57 185 procedure Resolve_If_Expression (N : Node_Id; Typ : Entity_Id);
5f50020a 186 procedure Resolve_Generalized_Indexing (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 187 procedure Resolve_Indexed_Component (N : Node_Id; Typ : Entity_Id);
188 procedure Resolve_Integer_Literal (N : Node_Id; Typ : Entity_Id);
189 procedure Resolve_Logical_Op (N : Node_Id; Typ : Entity_Id);
190 procedure Resolve_Membership_Op (N : Node_Id; Typ : Entity_Id);
191 procedure Resolve_Null (N : Node_Id; Typ : Entity_Id);
192 procedure Resolve_Operator_Symbol (N : Node_Id; Typ : Entity_Id);
193 procedure Resolve_Op_Concat (N : Node_Id; Typ : Entity_Id);
194 procedure Resolve_Op_Expon (N : Node_Id; Typ : Entity_Id);
195 procedure Resolve_Op_Not (N : Node_Id; Typ : Entity_Id);
196 procedure Resolve_Qualified_Expression (N : Node_Id; Typ : Entity_Id);
7610fee8 197 procedure Resolve_Raise_Expression (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 198 procedure Resolve_Range (N : Node_Id; Typ : Entity_Id);
199 procedure Resolve_Real_Literal (N : Node_Id; Typ : Entity_Id);
200 procedure Resolve_Reference (N : Node_Id; Typ : Entity_Id);
201 procedure Resolve_Selected_Component (N : Node_Id; Typ : Entity_Id);
202 procedure Resolve_Shift (N : Node_Id; Typ : Entity_Id);
203 procedure Resolve_Short_Circuit (N : Node_Id; Typ : Entity_Id);
204 procedure Resolve_Slice (N : Node_Id; Typ : Entity_Id);
205 procedure Resolve_String_Literal (N : Node_Id; Typ : Entity_Id);
ae33543c 206 procedure Resolve_Target_Name (N : Node_Id; Typ : Entity_Id);
996ae0b0
RK		 207 procedure Resolve_Type_Conversion (N : Node_Id; Typ : Entity_Id);
208 procedure Resolve_Unary_Op (N : Node_Id; Typ : Entity_Id);
209 procedure Resolve_Unchecked_Expression (N : Node_Id; Typ : Entity_Id);
210 procedure Resolve_Unchecked_Type_Conversion (N : Node_Id; Typ : Entity_Id);
211
212 function Operator_Kind
213 (Op_Name : Name_Id;
0ab80019 214 Is_Binary : Boolean) return Node_Kind;
996ae0b0
RK		 215 -- Utility to map the name of an operator into the corresponding Node. Used
216 -- by other node rewriting procedures.
217
218 procedure Resolve_Actuals (N : Node_Id; Nam : Entity_Id);
bc5f3720
RD		 219 -- Resolve actuals of call, and add default expressions for missing ones.
220 -- N is the Node_Id for the subprogram call, and Nam is the entity of the
221 -- called subprogram.
996ae0b0
RK		 222
223 procedure Resolve_Entry_Call (N : Node_Id; Typ : Entity_Id);
224 -- Called from Resolve_Call, when the prefix denotes an entry or element
225 -- of entry family. Actuals are resolved as for subprograms, and the node
226 -- is rebuilt as an entry call. Also called for protected operations. Typ
227 -- is the context type, which is used when the operation is a protected
228 -- function with no arguments, and the return value is indexed.
229
230 procedure Resolve_Intrinsic_Operator (N : Node_Id; Typ : Entity_Id);
5cc9353d
RD		 231 -- A call to a user-defined intrinsic operator is rewritten as a call to
232 -- the corresponding predefined operator, with suitable conversions. Note
233 -- that this applies only for intrinsic operators that denote predefined
234 -- operators, not ones that are intrinsic imports of back-end builtins.
996ae0b0 235
fbf5a39b 236 procedure Resolve_Intrinsic_Unary_Operator (N : Node_Id; Typ : Entity_Id);
7a5b62b0 237 -- Ditto, for arithmetic unary operators
fbf5a39b 238
996ae0b0
RK		 239 procedure Rewrite_Operator_As_Call (N : Node_Id; Nam : Entity_Id);
240 -- If an operator node resolves to a call to a user-defined operator,
241 -- rewrite the node as a function call.
242
243 procedure Make_Call_Into_Operator
244 (N : Node_Id;
245 Typ : Entity_Id;
246 Op_Id : Entity_Id);
247 -- Inverse transformation: if an operator is given in functional notation,
ac16e74c
RD		 248 -- then after resolving the node, transform into an operator node, so that
249 -- operands are resolved properly. Recall that predefined operators do not
250 -- have a full signature and special resolution rules apply.
996ae0b0 251
0ab80019
AC		 252 procedure Rewrite_Renamed_Operator
253 (N : Node_Id;
254 Op : Entity_Id;
255 Typ : Entity_Id);
21d7ef70 256 -- An operator can rename another, e.g. in an instantiation. In that
0ab80019 257 -- case, the proper operator node must be constructed and resolved.
996ae0b0
RK		 258
259 procedure Set_String_Literal_Subtype (N : Node_Id; Typ : Entity_Id);
260 -- The String_Literal_Subtype is built for all strings that are not
966fc9c5
AC		 261 -- operands of a static concatenation operation. If the argument is not
262 -- a N_String_Literal node, then the call has no effect.
996ae0b0
RK		 263
264 procedure Set_Slice_Subtype (N : Node_Id);
fbf5a39b 265 -- Build subtype of array type, with the range specified by the slice
996ae0b0 266
0669bebe
GB		 267 procedure Simplify_Type_Conversion (N : Node_Id);
268 -- Called after N has been resolved and evaluated, but before range checks
269 -- have been applied. Currently simplifies a combination of floating-point
24228312 270 -- to integer conversion and Rounding or Truncation attribute.
0669bebe 271
996ae0b0 272 function Unique_Fixed_Point_Type (N : Node_Id) return Entity_Id;
5cc9353d
RD		 273 -- A universal_fixed expression in an universal context is unambiguous if
274 -- there is only one applicable fixed point type. Determining whether there
275 -- is only one requires a search over all visible entities, and happens
276 -- only in very pathological cases (see 6115-006).
996ae0b0 277
996ae0b0
RK		 278 -------------------------
279 -- Ambiguous_Character --
280 -------------------------
281
282 procedure Ambiguous_Character (C : Node_Id) is
283 E : Entity_Id;
284
285 begin
286 if Nkind (C) = N_Character_Literal then
ed2233dc 287 Error_Msg_N ("ambiguous character literal", C);
b7d1f17f
HK		 288
289 -- First the ones in Standard
290
ed2233dc
AC		 291 Error_Msg_N ("\\possible interpretation: Character!", C);
292 Error_Msg_N ("\\possible interpretation: Wide_Character!", C);
b7d1f17f
HK		 293
294 -- Include Wide_Wide_Character in Ada 2005 mode
295
0791fbe9 296 if Ada_Version >= Ada_2005 then
ed2233dc 297 Error_Msg_N ("\\possible interpretation: Wide_Wide_Character!", C);
b7d1f17f
HK		 298 end if;
299
300 -- Now any other types that match
996ae0b0
RK		 301
302 E := Current_Entity (C);
1420b484 303 while Present (E) loop
ed2233dc 304 Error_Msg_NE ("\\possible interpretation:}!", C, Etype (E));
1420b484
JM		 305 E := Homonym (E);
306 end loop;
996ae0b0
RK		 307 end if;
308 end Ambiguous_Character;
309
310 -------------------------
311 -- Analyze_And_Resolve --
312 -------------------------
313
314 procedure Analyze_And_Resolve (N : Node_Id) is
315 begin
316 Analyze (N);
fbf5a39b 317 Resolve (N);
996ae0b0
RK		 318 end Analyze_And_Resolve;
319
320 procedure Analyze_And_Resolve (N : Node_Id; Typ : Entity_Id) is
321 begin
322 Analyze (N);
323 Resolve (N, Typ);
324 end Analyze_And_Resolve;
325
a91e9ac7 326 -- Versions with check(s) suppressed
996ae0b0
RK		 327
328 procedure Analyze_And_Resolve
329 (N : Node_Id;
330 Typ : Entity_Id;
331 Suppress : Check_Id)
332 is
fbf5a39b 333 Scop : constant Entity_Id := Current_Scope;
996ae0b0
RK		 334
335 begin
336 if Suppress = All_Checks then
337 declare
a7f1b24f 338 Sva : constant Suppress_Array := Scope_Suppress.Suppress;
996ae0b0 339 begin
a7f1b24f 340 Scope_Suppress.Suppress := (others => True);
996ae0b0 341 Analyze_And_Resolve (N, Typ);
a7f1b24f 342 Scope_Suppress.Suppress := Sva;
a91e9ac7
AC		 343 end;
344
996ae0b0
RK		 345 else
346 declare
3217f71e 347 Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
996ae0b0 348 begin
3217f71e 349 Scope_Suppress.Suppress (Suppress) := True;
996ae0b0 350 Analyze_And_Resolve (N, Typ);
3217f71e 351 Scope_Suppress.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
a7f1b24f 378 Sva : constant Suppress_Array := Scope_Suppress.Suppress;
a91e9ac7 379 begin
a7f1b24f 380 Scope_Suppress.Suppress := (others => True);
a91e9ac7 381 Analyze_And_Resolve (N);
a7f1b24f 382 Scope_Suppress.Suppress := Sva;
a91e9ac7
AC		 383 end;
384
996ae0b0
RK		 385 else
386 declare
3217f71e 387 Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
996ae0b0 388 begin
3217f71e 389 Scope_Suppress.Suppress (Suppress) := True;
996ae0b0 390 Analyze_And_Resolve (N);
3217f71e 391 Scope_Suppress.Suppress (Suppress) := Svg;
996ae0b0
RK		 392 end;
393 end if;
394
3217f71e 395 if Current_Scope /= Scop and then Scope_Is_Transient then
996ae0b0
RK		 396 Scope_Stack.Table (Scope_Stack.Last).Save_Scope_Suppress :=
397 Scope_Suppress;
398 end if;
399 end Analyze_And_Resolve;
400
401 ----------------------------
402 -- Check_Discriminant_Use --
403 ----------------------------
404
405 procedure Check_Discriminant_Use (N : Node_Id) is
406 PN : constant Node_Id := Parent (N);
407 Disc : constant Entity_Id := Entity (N);
408 P : Node_Id;
409 D : Node_Id;
410
411 begin
f3d0f304 412 -- Any use in a spec-expression is legal
996ae0b0 413
45fc7ddb 414 if In_Spec_Expression then
996ae0b0
RK		 415 null;
416
417 elsif Nkind (PN) = N_Range then
418
a77842bd 419 -- Discriminant cannot be used to constrain a scalar type
996ae0b0
RK		 420
421 P := Parent (PN);
422
423 if Nkind (P) = N_Range_Constraint
424 and then Nkind (Parent (P)) = N_Subtype_Indication
a397db96 425 and then Nkind (Parent (Parent (P))) = N_Component_Definition
996ae0b0
RK		 426 then
427 Error_Msg_N ("discriminant cannot constrain scalar type", N);
428
429 elsif Nkind (P) = N_Index_Or_Discriminant_Constraint then
430
5cc9353d 431 -- The following check catches the unusual case where a
966fc9c5
AC		 432 -- discriminant appears within an index constraint that is part
433 -- of a larger expression within a constraint on a component,
434 -- e.g. "C : Int range 1 .. F (new A(1 .. D))". For now we only
435 -- check case of record components, and note that a similar check
436 -- should also apply in the case of discriminant constraints
437 -- below. ???
996ae0b0
RK		 438
439 -- Note that the check for N_Subtype_Declaration below is to
440 -- detect the valid use of discriminants in the constraints of a
441 -- subtype declaration when this subtype declaration appears
442 -- inside the scope of a record type (which is syntactically
443 -- illegal, but which may be created as part of derived type
444 -- processing for records). See Sem_Ch3.Build_Derived_Record_Type
445 -- for more info.
446
447 if Ekind (Current_Scope) = E_Record_Type
448 and then Scope (Disc) = Current_Scope
449 and then not
450 (Nkind (Parent (P)) = N_Subtype_Indication
45fc7ddb
HK		 451 and then
452 Nkind_In (Parent (Parent (P)), N_Component_Definition,
453 N_Subtype_Declaration)
996ae0b0
RK		 454 and then Paren_Count (N) = 0)
455 then
456 Error_Msg_N
457 ("discriminant must appear alone in component constraint", N);
458 return;
459 end if;
460
a0ac3932 461 -- Detect a common error:
9bc43c53 462
996ae0b0 463 -- type R (D : Positive := 100) is record
9bc43c53 464 -- Name : String (1 .. D);
996ae0b0
RK		 465 -- end record;
466
a0ac3932
RD		 467 -- The default value causes an object of type R to be allocated
468 -- with room for Positive'Last characters. The RM does not mandate
469 -- the allocation of the maximum size, but that is what GNAT does
470 -- so we should warn the programmer that there is a problem.
996ae0b0 471
a0ac3932 472 Check_Large : declare
996ae0b0
RK		 473 SI : Node_Id;
474 T : Entity_Id;
475 TB : Node_Id;
476 CB : Entity_Id;
477
478 function Large_Storage_Type (T : Entity_Id) return Boolean;
5cc9353d
RD		 479 -- Return True if type T has a large enough range that any
480 -- array whose index type covered the whole range of the type
481 -- would likely raise Storage_Error.
996ae0b0 482
fbf5a39b
AC		 483 ------------------------
484 -- Large_Storage_Type --
485 ------------------------
486
996ae0b0
RK		 487 function Large_Storage_Type (T : Entity_Id) return Boolean is
488 begin
4b92fd3c
ST		 489 -- The type is considered large if its bounds are known at
490 -- compile time and if it requires at least as many bits as
491 -- a Positive to store the possible values.
492
493 return Compile_Time_Known_Value (Type_Low_Bound (T))
494 and then Compile_Time_Known_Value (Type_High_Bound (T))
495 and then
496 Minimum_Size (T, Biased => True) >=
a0ac3932 497 RM_Size (Standard_Positive);
996ae0b0
RK		 498 end Large_Storage_Type;
499
a0ac3932
RD		 500 -- Start of processing for Check_Large
501
996ae0b0
RK		 502 begin
503 -- Check that the Disc has a large range
504
505 if not Large_Storage_Type (Etype (Disc)) then
506 goto No_Danger;
507 end if;
508
509 -- If the enclosing type is limited, we allocate only the
510 -- default value, not the maximum, and there is no need for
511 -- a warning.
512
513 if Is_Limited_Type (Scope (Disc)) then
514 goto No_Danger;
515 end if;
516
517 -- Check that it is the high bound
518
519 if N /= High_Bound (PN)
c8ef728f 520 or else No (Discriminant_Default_Value (Disc))
996ae0b0
RK		 521 then
522 goto No_Danger;
523 end if;
524
5cc9353d
RD		 525 -- Check the array allows a large range at this bound. First
526 -- find the array
996ae0b0
RK		 527
528 SI := Parent (P);
529
530 if Nkind (SI) /= N_Subtype_Indication then
531 goto No_Danger;
532 end if;
533
534 T := Entity (Subtype_Mark (SI));
535
536 if not Is_Array_Type (T) then
537 goto No_Danger;
538 end if;
539
540 -- Next, find the dimension
541
542 TB := First_Index (T);
543 CB := First (Constraints (P));
544 while True
545 and then Present (TB)
546 and then Present (CB)
547 and then CB /= PN
548 loop
549 Next_Index (TB);
550 Next (CB);
551 end loop;
552
553 if CB /= PN then
554 goto No_Danger;
555 end if;
556
557 -- Now, check the dimension has a large range
558
559 if not Large_Storage_Type (Etype (TB)) then
560 goto No_Danger;
561 end if;
562
563 -- Warn about the danger
564
565 Error_Msg_N
324ac540 566 ("??creation of & object may raise Storage_Error!",
fbf5a39b 567 Scope (Disc));
996ae0b0
RK		 568
569 <<No_Danger>>
570 null;
571
a0ac3932 572 end Check_Large;
996ae0b0
RK		 573 end if;
574
575 -- Legal case is in index or discriminant constraint
576
45fc7ddb
HK		 577 elsif Nkind_In (PN, N_Index_Or_Discriminant_Constraint,
578 N_Discriminant_Association)
996ae0b0
RK		 579 then
580 if Paren_Count (N) > 0 then
581 Error_Msg_N
582 ("discriminant in constraint must appear alone", N);
758c442c
GD		 583
584 elsif Nkind (N) = N_Expanded_Name
585 and then Comes_From_Source (N)
586 then
587 Error_Msg_N
588 ("discriminant must appear alone as a direct name", N);
996ae0b0
RK		 589 end if;
590
591 return;
592
5cc9353d
RD		 593 -- Otherwise, context is an expression. It should not be within (i.e. a
594 -- subexpression of) a constraint for a component.
996ae0b0
RK		 595
596 else
597 D := PN;
598 P := Parent (PN);
45fc7ddb
HK		 599 while not Nkind_In (P, N_Component_Declaration,
600 N_Subtype_Indication,
601 N_Entry_Declaration)
996ae0b0
RK		 602 loop
603 D := P;
604 P := Parent (P);
605 exit when No (P);
606 end loop;
607
5cc9353d
RD		 608 -- If the discriminant is used in an expression that is a bound of a
609 -- scalar type, an Itype is created and the bounds are attached to
610 -- its range, not to the original subtype indication. Such use is of
611 -- course a double fault.
996ae0b0
RK		 612
613 if (Nkind (P) = N_Subtype_Indication
45fc7ddb
HK		 614 and then Nkind_In (Parent (P), N_Component_Definition,
615 N_Derived_Type_Definition)
996ae0b0
RK		 616 and then D = Constraint (P))
617
19fb051c
AC		 618 -- The constraint itself may be given by a subtype indication,
619 -- rather than by a more common discrete range.
996ae0b0
RK		 620
621 or else (Nkind (P) = N_Subtype_Indication
fbf5a39b
AC		 622 and then
623 Nkind (Parent (P)) = N_Index_Or_Discriminant_Constraint)
996ae0b0
RK		 624 or else Nkind (P) = N_Entry_Declaration
625 or else Nkind (D) = N_Defining_Identifier
626 then
627 Error_Msg_N
628 ("discriminant in constraint must appear alone", N);
629 end if;
630 end if;
631 end Check_Discriminant_Use;
632
633 --------------------------------
634 -- Check_For_Visible_Operator --
635 --------------------------------
636
637 procedure Check_For_Visible_Operator (N : Node_Id; T : Entity_Id) is
996ae0b0 638 begin
fbf5a39b 639 if Is_Invisible_Operator (N, T) then
305caf42 640 Error_Msg_NE -- CODEFIX
996ae0b0 641 ("operator for} is not directly visible!", N, First_Subtype (T));
305caf42
AC		 642 Error_Msg_N -- CODEFIX
643 ("use clause would make operation legal!", N);
996ae0b0
RK		 644 end if;
645 end Check_For_Visible_Operator;
646
c8ef728f
ES		 647 ----------------------------------
648 -- Check_Fully_Declared_Prefix --
649 ----------------------------------
650
651 procedure Check_Fully_Declared_Prefix
652 (Typ : Entity_Id;
653 Pref : Node_Id)
654 is
655 begin
656 -- Check that the designated type of the prefix of a dereference is
657 -- not an incomplete type. This cannot be done unconditionally, because
658 -- dereferences of private types are legal in default expressions. This
659 -- case is taken care of in Check_Fully_Declared, called below. There
660 -- are also 2005 cases where it is legal for the prefix to be unfrozen.
661
662 -- This consideration also applies to similar checks for allocators,
663 -- qualified expressions, and type conversions.
664
665 -- An additional exception concerns other per-object expressions that
666 -- are not directly related to component declarations, in particular
667 -- representation pragmas for tasks. These will be per-object
668 -- expressions if they depend on discriminants or some global entity.
669 -- If the task has access discriminants, the designated type may be
670 -- incomplete at the point the expression is resolved. This resolution
671 -- takes place within the body of the initialization procedure, where
672 -- the discriminant is replaced by its discriminal.
673
674 if Is_Entity_Name (Pref)
675 and then Ekind (Entity (Pref)) = E_In_Parameter
676 then
677 null;
678
679 -- Ada 2005 (AI-326): Tagged incomplete types allowed. The wrong usages
680 -- are handled by Analyze_Access_Attribute, Analyze_Assignment,
681 -- Analyze_Object_Renaming, and Freeze_Entity.
682
0791fbe9 683 elsif Ada_Version >= Ada_2005
c8ef728f 684 and then Is_Entity_Name (Pref)
811c6a85 685 and then Is_Access_Type (Etype (Pref))
c8ef728f
ES		 686 and then Ekind (Directly_Designated_Type (Etype (Pref))) =
687 E_Incomplete_Type
688 and then Is_Tagged_Type (Directly_Designated_Type (Etype (Pref)))
689 then
690 null;
691 else
692 Check_Fully_Declared (Typ, Parent (Pref));
693 end if;
694 end Check_Fully_Declared_Prefix;
695
996ae0b0
RK		 696 ------------------------------
697 -- Check_Infinite_Recursion --
698 ------------------------------
699
700 function Check_Infinite_Recursion (N : Node_Id) return Boolean is
701 P : Node_Id;
702 C : Node_Id;
703
07fc65c4 704 function Same_Argument_List return Boolean;
5cc9353d
RD		 705 -- Check whether list of actuals is identical to list of formals of
706 -- called function (which is also the enclosing scope).
07fc65c4
GB		 707
708 ------------------------
709 -- Same_Argument_List --
710 ------------------------
711
712 function Same_Argument_List return Boolean is
713 A : Node_Id;
714 F : Entity_Id;
715 Subp : Entity_Id;
716
717 begin
718 if not Is_Entity_Name (Name (N)) then
719 return False;
720 else
721 Subp := Entity (Name (N));
722 end if;
723
724 F := First_Formal (Subp);
725 A := First_Actual (N);
07fc65c4 726 while Present (F) and then Present (A) loop
445e5888 727 if not Is_Entity_Name (A) or else Entity (A) /= F then
07fc65c4
GB		 728 return False;
729 end if;
730
731 Next_Actual (A);
732 Next_Formal (F);
733 end loop;
734
735 return True;
736 end Same_Argument_List;
737
738 -- Start of processing for Check_Infinite_Recursion
739
996ae0b0 740 begin
26570b21
RD		 741 -- Special case, if this is a procedure call and is a call to the
742 -- current procedure with the same argument list, then this is for
743 -- sure an infinite recursion and we insert a call to raise SE.
744
745 if Is_List_Member (N)
746 and then List_Length (List_Containing (N)) = 1
747 and then Same_Argument_List
748 then
749 declare
750 P : constant Node_Id := Parent (N);
751 begin
752 if Nkind (P) = N_Handled_Sequence_Of_Statements
753 and then Nkind (Parent (P)) = N_Subprogram_Body
754 and then Is_Empty_List (Declarations (Parent (P)))
755 then
43417b90 756 Error_Msg_Warn := SPARK_Mode /= On;
4a28b181
AC		 757 Error_Msg_N ("!infinite recursion<<", N);
758 Error_Msg_N ("\!Storage_Error [<<", N);
26570b21
RD		 759 Insert_Action (N,
760 Make_Raise_Storage_Error (Sloc (N),
761 Reason => SE_Infinite_Recursion));
762 return True;
763 end if;
764 end;
765 end if;
766
767 -- If not that special case, search up tree, quitting if we reach a
768 -- construct (e.g. a conditional) that tells us that this is not a
769 -- case for an infinite recursion warning.
996ae0b0
RK		 770
771 C := N;
772 loop
773 P := Parent (C);
9a7da240
RD		 774
775 -- If no parent, then we were not inside a subprogram, this can for
776 -- example happen when processing certain pragmas in a spec. Just
777 -- return False in this case.
778
779 if No (P) then
780 return False;
781 end if;
782
783 -- Done if we get to subprogram body, this is definitely an infinite
784 -- recursion case if we did not find anything to stop us.
785
996ae0b0 786 exit when Nkind (P) = N_Subprogram_Body;
9a7da240
RD		 787
788 -- If appearing in conditional, result is false
789
45fc7ddb
HK		 790 if Nkind_In (P, N_Or_Else,
791 N_And_Then,
d347f572
AC		 792 N_Case_Expression,
793 N_Case_Statement,
9b16cb57 794 N_If_Expression,
d347f572 795 N_If_Statement)
996ae0b0
RK		 796 then
797 return False;
798
799 elsif Nkind (P) = N_Handled_Sequence_Of_Statements
800 and then C /= First (Statements (P))
801 then
26570b21
RD		 802 -- If the call is the expression of a return statement and the
803 -- actuals are identical to the formals, it's worth a warning.
804 -- However, we skip this if there is an immediately preceding
805 -- raise statement, since the call is never executed.
07fc65c4
GB		 806
807 -- Furthermore, this corresponds to a common idiom:
808
809 -- function F (L : Thing) return Boolean is
810 -- begin
811 -- raise Program_Error;
812 -- return F (L);
813 -- end F;
814
815 -- for generating a stub function
816
aa5147f0 817 if Nkind (Parent (N)) = N_Simple_Return_Statement
07fc65c4
GB		 818 and then Same_Argument_List
819 then
9ebe3743
HK		 820 exit when not Is_List_Member (Parent (N));
821
822 -- OK, return statement is in a statement list, look for raise
823
824 declare
825 Nod : Node_Id;
826
827 begin
828 -- Skip past N_Freeze_Entity nodes generated by expansion
829
830 Nod := Prev (Parent (N));
831 while Present (Nod)
832 and then Nkind (Nod) = N_Freeze_Entity
833 loop
834 Prev (Nod);
835 end loop;
836
3235dc87
AC		 837 -- If no raise statement, give warning. We look at the
838 -- original node, because in the case of "raise ... with
839 -- ...", the node has been transformed into a call.
9ebe3743 840
3235dc87 841 exit when Nkind (Original_Node (Nod)) /= N_Raise_Statement
9ebe3743
HK		 842 and then
843 (Nkind (Nod) not in N_Raise_xxx_Error
19fb051c 844 or else Present (Condition (Nod)));
9ebe3743 845 end;
07fc65c4
GB		 846 end if;
847
996ae0b0
RK		 848 return False;
849
850 else
851 C := P;
852 end if;
853 end loop;
854
43417b90 855 Error_Msg_Warn := SPARK_Mode /= On;
4a28b181
AC		 856 Error_Msg_N ("!possible infinite recursion<<", N);
857 Error_Msg_N ("\!??Storage_Error ]<<", N);
996ae0b0
RK		 858
859 return True;
860 end Check_Infinite_Recursion;
861
862 -------------------------------
863 -- Check_Initialization_Call --
864 -------------------------------
865
866 procedure Check_Initialization_Call (N : Entity_Id; Nam : Entity_Id) is
fbf5a39b 867 Typ : constant Entity_Id := Etype (First_Formal (Nam));
996ae0b0
RK		 868
869 function Uses_SS (T : Entity_Id) return Boolean;
07fc65c4
GB		 870 -- Check whether the creation of an object of the type will involve
871 -- use of the secondary stack. If T is a record type, this is true
f3d57416 872 -- if the expression for some component uses the secondary stack, e.g.
07fc65c4
GB		 873 -- through a call to a function that returns an unconstrained value.
874 -- False if T is controlled, because cleanups occur elsewhere.
875
876 -------------
877 -- Uses_SS --
878 -------------
996ae0b0
RK		 879
880 function Uses_SS (T : Entity_Id) return Boolean is
aa5147f0
ES		 881 Comp : Entity_Id;
882 Expr : Node_Id;
883 Full_Type : Entity_Id := Underlying_Type (T);
996ae0b0
RK		 884
885 begin
aa5147f0
ES		 886 -- Normally we want to use the underlying type, but if it's not set
887 -- then continue with T.
888
889 if not Present (Full_Type) then
890 Full_Type := T;
891 end if;
892
893 if Is_Controlled (Full_Type) then
996ae0b0
RK		 894 return False;
895
aa5147f0
ES		 896 elsif Is_Array_Type (Full_Type) then
897 return Uses_SS (Component_Type (Full_Type));
996ae0b0 898
aa5147f0
ES		 899 elsif Is_Record_Type (Full_Type) then
900 Comp := First_Component (Full_Type);
996ae0b0 901 while Present (Comp) loop
996ae0b0
RK		 902 if Ekind (Comp) = E_Component
903 and then Nkind (Parent (Comp)) = N_Component_Declaration
904 then
aa5147f0
ES		 905 -- The expression for a dynamic component may be rewritten
906 -- as a dereference, so retrieve original node.
907
908 Expr := Original_Node (Expression (Parent (Comp)));
996ae0b0 909
aa5147f0 910 -- Return True if the expression is a call to a function
1d57c04f
AC		 911 -- (including an attribute function such as Image, or a
912 -- user-defined operator) with a result that requires a
913 -- transient scope.
fbf5a39b 914
aa5147f0 915 if (Nkind (Expr) = N_Function_Call
1d57c04f 916 or else Nkind (Expr) in N_Op
aa5147f0
ES		 917 or else (Nkind (Expr) = N_Attribute_Reference
918 and then Present (Expressions (Expr))))
996ae0b0
RK		 919 and then Requires_Transient_Scope (Etype (Expr))
920 then
921 return True;
922
923 elsif Uses_SS (Etype (Comp)) then
924 return True;
925 end if;
926 end if;
927
928 Next_Component (Comp);
929 end loop;
930
931 return False;
932
933 else
934 return False;
935 end if;
936 end Uses_SS;
937
07fc65c4
GB		 938 -- Start of processing for Check_Initialization_Call
939
996ae0b0 940 begin
0669bebe 941 -- Establish a transient scope if the type needs it
07fc65c4 942
0669bebe 943 if Uses_SS (Typ) then
996ae0b0
RK		 944 Establish_Transient_Scope (First_Actual (N), Sec_Stack => True);
945 end if;
946 end Check_Initialization_Call;
947
f61580d4
AC		 948 ---------------------------------------
949 -- Check_No_Direct_Boolean_Operators --
950 ---------------------------------------
951
952 procedure Check_No_Direct_Boolean_Operators (N : Node_Id) is
953 begin
954 if Scope (Entity (N)) = Standard_Standard
955 and then Root_Type (Etype (Left_Opnd (N))) = Standard_Boolean
956 then
6fb4cdde 957 -- Restriction only applies to original source code
f61580d4 958
6fb4cdde 959 if Comes_From_Source (N) then
f61580d4
AC		 960 Check_Restriction (No_Direct_Boolean_Operators, N);
961 end if;
962 end if;
a36c1c3e 963
545d3e65
RD		 964 -- Do style check (but skip if in instance, error is on template)
965
a36c1c3e 966 if Style_Check then
545d3e65
RD		 967 if not In_Instance then
968 Check_Boolean_Operator (N);
969 end if;
a36c1c3e 970 end if;
f61580d4
AC		 971 end Check_No_Direct_Boolean_Operators;
972
996ae0b0
RK		 973 ------------------------------
974 -- Check_Parameterless_Call --
975 ------------------------------
976
977 procedure Check_Parameterless_Call (N : Node_Id) is
978 Nam : Node_Id;
979
bc5f3720
RD		 980 function Prefix_Is_Access_Subp return Boolean;
981 -- If the prefix is of an access_to_subprogram type, the node must be
982 -- rewritten as a call. Ditto if the prefix is overloaded and all its
983 -- interpretations are access to subprograms.
984
985 ---------------------------
986 -- Prefix_Is_Access_Subp --
987 ---------------------------
988
989 function Prefix_Is_Access_Subp return Boolean is
990 I : Interp_Index;
991 It : Interp;
992
993 begin
22b77f68 994 -- If the context is an attribute reference that can apply to
b4a4936b 995 -- functions, this is never a parameterless call (RM 4.1.4(6)).
96d2756f
AC		 996
997 if Nkind (Parent (N)) = N_Attribute_Reference
b69cd36a
AC		 998 and then Nam_In (Attribute_Name (Parent (N)), Name_Address,
999 Name_Code_Address,
1000 Name_Access)
96d2756f
AC		 1001 then
1002 return False;
1003 end if;
1004
bc5f3720
RD		 1005 if not Is_Overloaded (N) then
1006 return
1007 Ekind (Etype (N)) = E_Subprogram_Type
1008 and then Base_Type (Etype (Etype (N))) /= Standard_Void_Type;
1009 else
1010 Get_First_Interp (N, I, It);
1011 while Present (It.Typ) loop
1012 if Ekind (It.Typ) /= E_Subprogram_Type
1013 or else Base_Type (Etype (It.Typ)) = Standard_Void_Type
1014 then
1015 return False;
1016 end if;
1017
1018 Get_Next_Interp (I, It);
1019 end loop;
1020
1021 return True;
1022 end if;
1023 end Prefix_Is_Access_Subp;
1024
1025 -- Start of processing for Check_Parameterless_Call
1026
996ae0b0 1027 begin
07fc65c4
GB		 1028 -- Defend against junk stuff if errors already detected
1029
1030 if Total_Errors_Detected /= 0 then
1031 if Nkind (N) in N_Has_Etype and then Etype (N) = Any_Type then
1032 return;
1033 elsif Nkind (N) in N_Has_Chars
1034 and then Chars (N) in Error_Name_Or_No_Name
1035 then
1036 return;
1037 end if;
fbf5a39b
AC		 1038
1039 Require_Entity (N);
996ae0b0
RK		 1040 end if;
1041
45fc7ddb
HK		 1042 -- If the context expects a value, and the name is a procedure, this is
1043 -- most likely a missing 'Access. Don't try to resolve the parameterless
1044 -- call, error will be caught when the outer call is analyzed.
18c0ecbe
AC		 1045
1046 if Is_Entity_Name (N)
1047 and then Ekind (Entity (N)) = E_Procedure
1048 and then not Is_Overloaded (N)
1049 and then
45fc7ddb
HK		 1050 Nkind_In (Parent (N), N_Parameter_Association,
1051 N_Function_Call,
1052 N_Procedure_Call_Statement)
18c0ecbe
AC		 1053 then
1054 return;
1055 end if;
1056
45fc7ddb
HK		 1057 -- Rewrite as call if overloadable entity that is (or could be, in the
1058 -- overloaded case) a function call. If we know for sure that the entity
1059 -- is an enumeration literal, we do not rewrite it.
f4b049db 1060
e1d9659d
AC		 1061 -- If the entity is the name of an operator, it cannot be a call because
1062 -- operators cannot have default parameters. In this case, this must be
1063 -- a string whose contents coincide with an operator name. Set the kind
96d2756f 1064 -- of the node appropriately.
996ae0b0
RK		 1065
1066 if (Is_Entity_Name (N)
e1d9659d 1067 and then Nkind (N) /= N_Operator_Symbol
996ae0b0
RK		 1068 and then Is_Overloadable (Entity (N))
1069 and then (Ekind (Entity (N)) /= E_Enumeration_Literal
964f13da 1070 or else Is_Overloaded (N)))
996ae0b0 1071
09494c32 1072 -- Rewrite as call if it is an explicit dereference of an expression of
f3d57416 1073 -- a subprogram access type, and the subprogram type is not that of a
996ae0b0
RK		 1074 -- procedure or entry.
1075
1076 or else
bc5f3720 1077 (Nkind (N) = N_Explicit_Dereference and then Prefix_Is_Access_Subp)
996ae0b0
RK		 1078
1079 -- Rewrite as call if it is a selected component which is a function,
1080 -- this is the case of a call to a protected function (which may be
1081 -- overloaded with other protected operations).
1082
1083 or else
1084 (Nkind (N) = N_Selected_Component
1085 and then (Ekind (Entity (Selector_Name (N))) = E_Function
964f13da
RD		 1086 or else
1087 (Ekind_In (Entity (Selector_Name (N)), E_Entry,
1088 E_Procedure)
1089 and then Is_Overloaded (Selector_Name (N)))))
996ae0b0 1090
5cc9353d
RD		 1091 -- If one of the above three conditions is met, rewrite as call. Apply
1092 -- the rewriting only once.
996ae0b0
RK		 1093
1094 then
1095 if Nkind (Parent (N)) /= N_Function_Call
1096 or else N /= Name (Parent (N))
1097 then
747de90b
AC		 1098
1099 -- This may be a prefixed call that was not fully analyzed, e.g.
1100 -- an actual in an instance.
1101
1102 if Ada_Version >= Ada_2005
1103 and then Nkind (N) = N_Selected_Component
1104 and then Is_Dispatching_Operation (Entity (Selector_Name (N)))
1105 then
1106 Analyze_Selected_Component (N);
996c8821 1107
747de90b
AC		 1108 if Nkind (N) /= N_Selected_Component then
1109 return;
1110 end if;
1111 end if;
1112
b80a2b4b
AC		 1113 -- The node is the name of the parameterless call. Preserve its
1114 -- descendants, which may be complex expressions.
1115
1116 Nam := Relocate_Node (N);
996ae0b0 1117
bc5f3720 1118 -- If overloaded, overload set belongs to new copy
996ae0b0
RK		 1119
1120 Save_Interps (N, Nam);
1121
1122 -- Change node to parameterless function call (note that the
1123 -- Parameter_Associations associations field is left set to Empty,
1124 -- its normal default value since there are no parameters)
1125
1126 Change_Node (N, N_Function_Call);
1127 Set_Name (N, Nam);
1128 Set_Sloc (N, Sloc (Nam));
1129 Analyze_Call (N);
1130 end if;
1131
1132 elsif Nkind (N) = N_Parameter_Association then
1133 Check_Parameterless_Call (Explicit_Actual_Parameter (N));
e1d9659d
AC		 1134
1135 elsif Nkind (N) = N_Operator_Symbol then
1136 Change_Operator_Symbol_To_String_Literal (N);
1137 Set_Is_Overloaded (N, False);
1138 Set_Etype (N, Any_String);
996ae0b0
RK		 1139 end if;
1140 end Check_Parameterless_Call;
1141
c2a2dbcc
RD		 1142 --------------------------------
1143 -- Is_Atomic_Ref_With_Address --
1144 --------------------------------
1145
1146 function Is_Atomic_Ref_With_Address (N : Node_Id) return Boolean is
1147 Pref : constant Node_Id := Prefix (N);
1148
1149 begin
1150 if not Is_Entity_Name (Pref) then
1151 return False;
1152
1153 else
1154 declare
1155 Pent : constant Entity_Id := Entity (Pref);
1156 Ptyp : constant Entity_Id := Etype (Pent);
1157 begin
1158 return not Is_Access_Type (Ptyp)
1159 and then (Is_Atomic (Ptyp) or else Is_Atomic (Pent))
1160 and then Present (Address_Clause (Pent));
1161 end;
1162 end if;
1163 end Is_Atomic_Ref_With_Address;
1164
67ce0d7e
RD		 1165 -----------------------------
1166 -- Is_Definite_Access_Type --
1167 -----------------------------
1168
1169 function Is_Definite_Access_Type (E : Entity_Id) return Boolean is
1170 Btyp : constant Entity_Id := Base_Type (E);
1171 begin
1172 return Ekind (Btyp) = E_Access_Type
1173 or else (Ekind (Btyp) = E_Access_Subprogram_Type
72e9f2b9 1174 and then Comes_From_Source (Btyp));
67ce0d7e
RD		 1175 end Is_Definite_Access_Type;
1176
996ae0b0
RK		 1177 ----------------------
1178 -- Is_Predefined_Op --
1179 ----------------------
1180
1181 function Is_Predefined_Op (Nam : Entity_Id) return Boolean is
1182 begin
6a497607
AC		 1183 -- Predefined operators are intrinsic subprograms
1184
1185 if not Is_Intrinsic_Subprogram (Nam) then
1186 return False;
1187 end if;
1188
1189 -- A call to a back-end builtin is never a predefined operator
1190
1191 if Is_Imported (Nam) and then Present (Interface_Name (Nam)) then
1192 return False;
1193 end if;
1194
1195 return not Is_Generic_Instance (Nam)
996ae0b0 1196 and then Chars (Nam) in Any_Operator_Name
6a497607 1197 and then (No (Alias (Nam)) or else Is_Predefined_Op (Alias (Nam)));
996ae0b0
RK		 1198 end Is_Predefined_Op;
1199
1200 -----------------------------
1201 -- Make_Call_Into_Operator --
1202 -----------------------------
1203
1204 procedure Make_Call_Into_Operator
1205 (N : Node_Id;
1206 Typ : Entity_Id;
1207 Op_Id : Entity_Id)
1208 is
1209 Op_Name : constant Name_Id := Chars (Op_Id);
1210 Act1 : Node_Id := First_Actual (N);
1211 Act2 : Node_Id := Next_Actual (Act1);
1212 Error : Boolean := False;
2820d220
AC		 1213 Func : constant Entity_Id := Entity (Name (N));
1214 Is_Binary : constant Boolean := Present (Act2);
996ae0b0
RK		 1215 Op_Node : Node_Id;
1216 Opnd_Type : Entity_Id;
1217 Orig_Type : Entity_Id := Empty;
1218 Pack : Entity_Id;
1219
1220 type Kind_Test is access function (E : Entity_Id) return Boolean;
1221
996ae0b0 1222 function Operand_Type_In_Scope (S : Entity_Id) return Boolean;
b4a4936b
AC		 1223 -- If the operand is not universal, and the operator is given by an
1224 -- expanded name, verify that the operand has an interpretation with a
1225 -- type defined in the given scope of the operator.
996ae0b0
RK		 1226
1227 function Type_In_P (Test : Kind_Test) return Entity_Id;
b4a4936b
AC		 1228 -- Find a type of the given class in package Pack that contains the
1229 -- operator.
996ae0b0 1230
996ae0b0
RK		 1231 ---------------------------
1232 -- Operand_Type_In_Scope --
1233 ---------------------------
1234
1235 function Operand_Type_In_Scope (S : Entity_Id) return Boolean is
1236 Nod : constant Node_Id := Right_Opnd (Op_Node);
1237 I : Interp_Index;
1238 It : Interp;
1239
1240 begin
1241 if not Is_Overloaded (Nod) then
1242 return Scope (Base_Type (Etype (Nod))) = S;
1243
1244 else
1245 Get_First_Interp (Nod, I, It);
996ae0b0 1246 while Present (It.Typ) loop
996ae0b0
RK		 1247 if Scope (Base_Type (It.Typ)) = S then
1248 return True;
1249 end if;
1250
1251 Get_Next_Interp (I, It);
1252 end loop;
1253
1254 return False;
1255 end if;
1256 end Operand_Type_In_Scope;
1257
1258 ---------------
1259 -- Type_In_P --
1260 ---------------
1261
1262 function Type_In_P (Test : Kind_Test) return Entity_Id is
1263 E : Entity_Id;
1264
1265 function In_Decl return Boolean;
1266 -- Verify that node is not part of the type declaration for the
1267 -- candidate type, which would otherwise be invisible.
1268
1269 -------------
1270 -- In_Decl --
1271 -------------
1272
1273 function In_Decl return Boolean is
1274 Decl_Node : constant Node_Id := Parent (E);
1275 N2 : Node_Id;
1276
1277 begin
1278 N2 := N;
1279
1280 if Etype (E) = Any_Type then
1281 return True;
1282
1283 elsif No (Decl_Node) then
1284 return False;
1285
1286 else
1287 while Present (N2)
1288 and then Nkind (N2) /= N_Compilation_Unit
1289 loop
1290 if N2 = Decl_Node then
1291 return True;
1292 else
1293 N2 := Parent (N2);
1294 end if;
1295 end loop;
1296
1297 return False;
1298 end if;
1299 end In_Decl;
1300
1301 -- Start of processing for Type_In_P
1302
1303 begin
b4a4936b
AC		 1304 -- If the context type is declared in the prefix package, this is the
1305 -- desired base type.
996ae0b0 1306
b4a4936b 1307 if Scope (Base_Type (Typ)) = Pack and then Test (Typ) then
996ae0b0
RK		 1308 return Base_Type (Typ);
1309
1310 else
1311 E := First_Entity (Pack);
996ae0b0 1312 while Present (E) loop
445e5888 1313 if Test (E) and then not In_Decl then
996ae0b0
RK		 1314 return E;
1315 end if;
1316
1317 Next_Entity (E);
1318 end loop;
1319
1320 return Empty;
1321 end if;
1322 end Type_In_P;
1323
996ae0b0
RK		 1324 -- Start of processing for Make_Call_Into_Operator
1325
1326 begin
1327 Op_Node := New_Node (Operator_Kind (Op_Name, Is_Binary), Sloc (N));
1328
1329 -- Binary operator
1330
1331 if Is_Binary then
1332 Set_Left_Opnd (Op_Node, Relocate_Node (Act1));
1333 Set_Right_Opnd (Op_Node, Relocate_Node (Act2));
1334 Save_Interps (Act1, Left_Opnd (Op_Node));
1335 Save_Interps (Act2, Right_Opnd (Op_Node));
1336 Act1 := Left_Opnd (Op_Node);
1337 Act2 := Right_Opnd (Op_Node);
1338
1339 -- Unary operator
1340
1341 else
1342 Set_Right_Opnd (Op_Node, Relocate_Node (Act1));
1343 Save_Interps (Act1, Right_Opnd (Op_Node));
1344 Act1 := Right_Opnd (Op_Node);
1345 end if;
1346
1347 -- If the operator is denoted by an expanded name, and the prefix is
1348 -- not Standard, but the operator is a predefined one whose scope is
1349 -- Standard, then this is an implicit_operator, inserted as an
1350 -- interpretation by the procedure of the same name. This procedure
1351 -- overestimates the presence of implicit operators, because it does
1352 -- not examine the type of the operands. Verify now that the operand
1353 -- type appears in the given scope. If right operand is universal,
1354 -- check the other operand. In the case of concatenation, either
1355 -- argument can be the component type, so check the type of the result.
1356 -- If both arguments are literals, look for a type of the right kind
1357 -- defined in the given scope. This elaborate nonsense is brought to
1358 -- you courtesy of b33302a. The type itself must be frozen, so we must
1359 -- find the type of the proper class in the given scope.
1360
06f2efd7
TQ		 1361 -- A final wrinkle is the multiplication operator for fixed point types,
1362 -- which is defined in Standard only, and not in the scope of the
b4a4936b 1363 -- fixed point type itself.
996ae0b0
RK		 1364
1365 if Nkind (Name (N)) = N_Expanded_Name then
1366 Pack := Entity (Prefix (Name (N)));
1367
1115dd7e
ES		 1368 -- If this is a package renaming, get renamed entity, which will be
1369 -- the scope of the operands if operaton is type-correct.
1370
1371 if Present (Renamed_Entity (Pack)) then
1372 Pack := Renamed_Entity (Pack);
1373 end if;
1374
06f2efd7
TQ		 1375 -- If the entity being called is defined in the given package, it is
1376 -- a renaming of a predefined operator, and known to be legal.
996ae0b0
RK		 1377
1378 if Scope (Entity (Name (N))) = Pack
1379 and then Pack /= Standard_Standard
1380 then
1381 null;
1382
9ebe3743
HK		 1383 -- Visibility does not need to be checked in an instance: if the
1384 -- operator was not visible in the generic it has been diagnosed
1385 -- already, else there is an implicit copy of it in the instance.
1386
1387 elsif In_Instance then
1388 null;
1389
b69cd36a 1390 elsif Nam_In (Op_Name, Name_Op_Multiply, Name_Op_Divide)
996ae0b0
RK		 1391 and then Is_Fixed_Point_Type (Etype (Left_Opnd (Op_Node)))
1392 and then Is_Fixed_Point_Type (Etype (Right_Opnd (Op_Node)))
1393 then
1394 if Pack /= Standard_Standard then
1395 Error := True;
1396 end if;
1397
b4a4936b 1398 -- Ada 2005 AI-420: Predefined equality on Universal_Access is
06f2efd7 1399 -- available.
c8ef728f 1400
0791fbe9 1401 elsif Ada_Version >= Ada_2005
b69cd36a 1402 and then Nam_In (Op_Name, Name_Op_Eq, Name_Op_Ne)
c8ef728f
ES		 1403 and then Ekind (Etype (Act1)) = E_Anonymous_Access_Type
1404 then
1405 null;
1406
996ae0b0
RK		 1407 else
1408 Opnd_Type := Base_Type (Etype (Right_Opnd (Op_Node)));
1409
1410 if Op_Name = Name_Op_Concat then
1411 Opnd_Type := Base_Type (Typ);
1412
1413 elsif (Scope (Opnd_Type) = Standard_Standard
d8f43ee6 1414 and then Is_Binary)
996ae0b0
RK		 1415 or else (Nkind (Right_Opnd (Op_Node)) = N_Attribute_Reference
1416 and then Is_Binary
1417 and then not Comes_From_Source (Opnd_Type))
1418 then
1419 Opnd_Type := Base_Type (Etype (Left_Opnd (Op_Node)));
1420 end if;
1421
1422 if Scope (Opnd_Type) = Standard_Standard then
1423
1424 -- Verify that the scope contains a type that corresponds to
1425 -- the given literal. Optimize the case where Pack is Standard.
1426
1427 if Pack /= Standard_Standard then
996ae0b0 1428 if Opnd_Type = Universal_Integer then
06f2efd7 1429 Orig_Type := Type_In_P (Is_Integer_Type'Access);
996ae0b0
RK		 1430
1431 elsif Opnd_Type = Universal_Real then
1432 Orig_Type := Type_In_P (Is_Real_Type'Access);
1433
1434 elsif Opnd_Type = Any_String then
1435 Orig_Type := Type_In_P (Is_String_Type'Access);
1436
1437 elsif Opnd_Type = Any_Access then
06f2efd7 1438 Orig_Type := Type_In_P (Is_Definite_Access_Type'Access);
996ae0b0
RK		 1439
1440 elsif Opnd_Type = Any_Composite then
1441 Orig_Type := Type_In_P (Is_Composite_Type'Access);
1442
1443 if Present (Orig_Type) then
1444 if Has_Private_Component (Orig_Type) then
1445 Orig_Type := Empty;
1446 else
1447 Set_Etype (Act1, Orig_Type);
1448
1449 if Is_Binary then
1450 Set_Etype (Act2, Orig_Type);
1451 end if;
1452 end if;
1453 end if;
1454
1455 else
1456 Orig_Type := Empty;
1457 end if;
1458
1459 Error := No (Orig_Type);
1460 end if;
1461
1462 elsif Ekind (Opnd_Type) = E_Allocator_Type
1463 and then No (Type_In_P (Is_Definite_Access_Type'Access))
1464 then
1465 Error := True;
1466
1467 -- If the type is defined elsewhere, and the operator is not
1468 -- defined in the given scope (by a renaming declaration, e.g.)
1469 -- then this is an error as well. If an extension of System is
1470 -- present, and the type may be defined there, Pack must be
1471 -- System itself.
1472
1473 elsif Scope (Opnd_Type) /= Pack
1474 and then Scope (Op_Id) /= Pack
1475 and then (No (System_Aux_Id)
1476 or else Scope (Opnd_Type) /= System_Aux_Id
1477 or else Pack /= Scope (System_Aux_Id))
1478 then
244e5a2c
AC		 1479 if not Is_Overloaded (Right_Opnd (Op_Node)) then
1480 Error := True;
1481 else
1482 Error := not Operand_Type_In_Scope (Pack);
1483 end if;
996ae0b0
RK		 1484
1485 elsif Pack = Standard_Standard
1486 and then not Operand_Type_In_Scope (Standard_Standard)
1487 then
1488 Error := True;
1489 end if;
1490 end if;
1491
1492 if Error then
1493 Error_Msg_Node_2 := Pack;
1494 Error_Msg_NE
1495 ("& not declared in&", N, Selector_Name (Name (N)));
1496 Set_Etype (N, Any_Type);
1497 return;
88b17d45
AC		 1498
1499 -- Detect a mismatch between the context type and the result type
1500 -- in the named package, which is otherwise not detected if the
1501 -- operands are universal. Check is only needed if source entity is
1502 -- an operator, not a function that renames an operator.
1503
1504 elsif Nkind (Parent (N)) /= N_Type_Conversion
1505 and then Ekind (Entity (Name (N))) = E_Operator
1506 and then Is_Numeric_Type (Typ)
1507 and then not Is_Universal_Numeric_Type (Typ)
1508 and then Scope (Base_Type (Typ)) /= Pack
1509 and then not In_Instance
1510 then
1511 if Is_Fixed_Point_Type (Typ)
b69cd36a 1512 and then Nam_In (Op_Name, Name_Op_Multiply, Name_Op_Divide)
88b17d45
AC		 1513 then
1514 -- Already checked above
1515
1516 null;
1517
e86a3a7e 1518 -- Operator may be defined in an extension of System
80c3be7a
AC		 1519
1520 elsif Present (System_Aux_Id)
1521 and then Scope (Opnd_Type) = System_Aux_Id
1522 then
1523 null;
1524
88b17d45 1525 else
be5a1b93
TQ		 1526 -- Could we use Wrong_Type here??? (this would require setting
1527 -- Etype (N) to the actual type found where Typ was expected).
1528
e86a3a7e 1529 Error_Msg_NE ("expect }", N, Typ);
88b17d45 1530 end if;
996ae0b0
RK		 1531 end if;
1532 end if;
1533
1534 Set_Chars (Op_Node, Op_Name);
fbf5a39b
AC		 1535
1536 if not Is_Private_Type (Etype (N)) then
1537 Set_Etype (Op_Node, Base_Type (Etype (N)));
1538 else
1539 Set_Etype (Op_Node, Etype (N));
1540 end if;
1541
2820d220
AC		 1542 -- If this is a call to a function that renames a predefined equality,
1543 -- the renaming declaration provides a type that must be used to
1544 -- resolve the operands. This must be done now because resolution of
1545 -- the equality node will not resolve any remaining ambiguity, and it
1546 -- assumes that the first operand is not overloaded.
1547
b69cd36a 1548 if Nam_In (Op_Name, Name_Op_Eq, Name_Op_Ne)
2820d220
AC		 1549 and then Ekind (Func) = E_Function
1550 and then Is_Overloaded (Act1)
1551 then
1552 Resolve (Act1, Base_Type (Etype (First_Formal (Func))));
1553 Resolve (Act2, Base_Type (Etype (First_Formal (Func))));
1554 end if;
1555
996ae0b0
RK		 1556 Set_Entity (Op_Node, Op_Id);
1557 Generate_Reference (Op_Id, N, ' ');
45fc7ddb
HK		 1558
1559 -- Do rewrite setting Comes_From_Source on the result if the original
1560 -- call came from source. Although it is not strictly the case that the
1561 -- operator as such comes from the source, logically it corresponds
1562 -- exactly to the function call in the source, so it should be marked
1563 -- this way (e.g. to make sure that validity checks work fine).
1564
1565 declare
1566 CS : constant Boolean := Comes_From_Source (N);
1567 begin
1568 Rewrite (N, Op_Node);
1569 Set_Comes_From_Source (N, CS);
1570 end;
fbf5a39b
AC		 1571
1572 -- If this is an arithmetic operator and the result type is private,
1573 -- the operands and the result must be wrapped in conversion to
1574 -- expose the underlying numeric type and expand the proper checks,
1575 -- e.g. on division.
1576
1577 if Is_Private_Type (Typ) then
1578 case Nkind (N) is
d8f43ee6
HK		 1579 when N_Op_Add
1580 | N_Op_Divide
1581 | N_Op_Expon
1582 | N_Op_Mod
1583 | N_Op_Multiply
1584 | N_Op_Rem
1585 | N_Op_Subtract
1586 =>
fbf5a39b
AC		 1587 Resolve_Intrinsic_Operator (N, Typ);
1588
d8f43ee6
HK		 1589 when N_Op_Abs
1590 | N_Op_Minus
1591 | N_Op_Plus
1592 =>
fbf5a39b
AC		 1593 Resolve_Intrinsic_Unary_Operator (N, Typ);
1594
1595 when others =>
1596 Resolve (N, Typ);
1597 end case;
1598 else
1599 Resolve (N, Typ);
1600 end if;
466c2127
AC		 1601
1602 -- If in ASIS_Mode, propagate operand types to original actuals of
d7a3e18c 1603 -- function call, which would otherwise not be fully resolved. If
00ba7be8
AC		 1604 -- the call has already been constant-folded, nothing to do. We
1605 -- relocate the operand nodes rather than copy them, to preserve
1606 -- original_node pointers, given that the operands themselves may
c61ef416
AC		 1607 -- have been rewritten. If the call was itself a rewriting of an
1608 -- operator node, nothing to do.
466c2127 1609
c61ef416
AC		 1610 if ASIS_Mode
1611 and then Nkind (N) in N_Op
1612 and then Nkind (Original_Node (N)) = N_Function_Call
1613 then
c05ba1f1 1614 declare
5fde9688 1615 L : Node_Id;
c05ba1f1
AC		 1616 R : constant Node_Id := Right_Opnd (N);
1617
1618 Old_First : constant Node_Id :=
1619 First (Parameter_Associations (Original_Node (N)));
1620 Old_Sec : Node_Id;
1621
1622 begin
1623 if Is_Binary then
5fde9688
AC		 1624 L := Left_Opnd (N);
1625 Old_Sec := Next (Old_First);
c05ba1f1
AC		 1626
1627 -- If the original call has named associations, replace the
1628 -- explicit actual parameter in the association with the proper
1629 -- resolved operand.
1630
1631 if Nkind (Old_First) = N_Parameter_Association then
1632 if Chars (Selector_Name (Old_First)) =
1633 Chars (First_Entity (Op_Id))
1634 then
1635 Rewrite (Explicit_Actual_Parameter (Old_First),
1636 Relocate_Node (L));
1637 else
1638 Rewrite (Explicit_Actual_Parameter (Old_First),
1639 Relocate_Node (R));
1640 end if;
1641
1642 else
1643 Rewrite (Old_First, Relocate_Node (L));
1644 end if;
1645
1646 if Nkind (Old_Sec) = N_Parameter_Association then
7dae9ca0 1647 if Chars (Selector_Name (Old_Sec)) =
c05ba1f1
AC		 1648 Chars (First_Entity (Op_Id))
1649 then
1650 Rewrite (Explicit_Actual_Parameter (Old_Sec),
1651 Relocate_Node (L));
1652 else
1653 Rewrite (Explicit_Actual_Parameter (Old_Sec),
1654 Relocate_Node (R));
1655 end if;
1656
1657 else
1658 Rewrite (Old_Sec, Relocate_Node (R));
1659 end if;
1660
1661 else
1662 if Nkind (Old_First) = N_Parameter_Association then
1663 Rewrite (Explicit_Actual_Parameter (Old_First),
1664 Relocate_Node (R));
1665 else
1666 Rewrite (Old_First, Relocate_Node (R));
1667 end if;
1668 end if;
1669 end;
3699edc4
AC		 1670
1671 Set_Parent (Original_Node (N), Parent (N));
466c2127 1672 end if;
996ae0b0
RK		 1673 end Make_Call_Into_Operator;
1674
1675 -------------------
1676 -- Operator_Kind --
1677 -------------------
1678
1679 function Operator_Kind
1680 (Op_Name : Name_Id;
0ab80019 1681 Is_Binary : Boolean) return Node_Kind
996ae0b0
RK		 1682 is
1683 Kind : Node_Kind;
1684
1685 begin
b0186f71
AC		 1686 -- Use CASE statement or array???
1687
996ae0b0 1688 if Is_Binary then
1b1d88b1 1689 if Op_Name = Name_Op_And then
aa5147f0 1690 Kind := N_Op_And;
1b1d88b1 1691 elsif Op_Name = Name_Op_Or then
aa5147f0 1692 Kind := N_Op_Or;
1b1d88b1 1693 elsif Op_Name = Name_Op_Xor then
aa5147f0 1694 Kind := N_Op_Xor;
1b1d88b1 1695 elsif Op_Name = Name_Op_Eq then
aa5147f0 1696 Kind := N_Op_Eq;
1b1d88b1 1697 elsif Op_Name = Name_Op_Ne then
aa5147f0 1698 Kind := N_Op_Ne;
1b1d88b1 1699 elsif Op_Name = Name_Op_Lt then
aa5147f0 1700 Kind := N_Op_Lt;
1b1d88b1 1701 elsif Op_Name = Name_Op_Le then
aa5147f0 1702 Kind := N_Op_Le;
1b1d88b1 1703 elsif Op_Name = Name_Op_Gt then
aa5147f0 1704 Kind := N_Op_Gt;
1b1d88b1 1705 elsif Op_Name = Name_Op_Ge then
aa5147f0 1706 Kind := N_Op_Ge;
1b1d88b1 1707 elsif Op_Name = Name_Op_Add then
aa5147f0 1708 Kind := N_Op_Add;
1b1d88b1 1709 elsif Op_Name = Name_Op_Subtract then
aa5147f0 1710 Kind := N_Op_Subtract;
1b1d88b1 1711 elsif Op_Name = Name_Op_Concat then
aa5147f0 1712 Kind := N_Op_Concat;
1b1d88b1 1713 elsif Op_Name = Name_Op_Multiply then
aa5147f0 1714 Kind := N_Op_Multiply;
1b1d88b1 1715 elsif Op_Name = Name_Op_Divide then
aa5147f0 1716 Kind := N_Op_Divide;
1b1d88b1 1717 elsif Op_Name = Name_Op_Mod then
aa5147f0 1718 Kind := N_Op_Mod;
1b1d88b1 1719 elsif Op_Name = Name_Op_Rem then
aa5147f0 1720 Kind := N_Op_Rem;
1b1d88b1 1721 elsif Op_Name = Name_Op_Expon then
aa5147f0 1722 Kind := N_Op_Expon;
996ae0b0
RK		 1723 else
1724 raise Program_Error;
1725 end if;
1726
1727 -- Unary operators
1728
1729 else
1b1d88b1 1730 if Op_Name = Name_Op_Add then
aa5147f0 1731 Kind := N_Op_Plus;
1b1d88b1 1732 elsif Op_Name = Name_Op_Subtract then
aa5147f0 1733 Kind := N_Op_Minus;
1b1d88b1 1734 elsif Op_Name = Name_Op_Abs then
aa5147f0 1735 Kind := N_Op_Abs;
1b1d88b1 1736 elsif Op_Name = Name_Op_Not then
aa5147f0 1737 Kind := N_Op_Not;
996ae0b0
RK		 1738 else
1739 raise Program_Error;
1740 end if;
1741 end if;
1742
1743 return Kind;
1744 end Operator_Kind;
1745
45fc7ddb
HK		 1746 ----------------------------
1747 -- Preanalyze_And_Resolve --
1748 ----------------------------
996ae0b0 1749
45fc7ddb 1750 procedure Preanalyze_And_Resolve (N : Node_Id; T : Entity_Id) is
996ae0b0
RK		 1751 Save_Full_Analysis : constant Boolean := Full_Analysis;
1752
1753 begin
1754 Full_Analysis := False;
1755 Expander_Mode_Save_And_Set (False);
1756
a7f1b24f
RD		 1757 -- Normally, we suppress all checks for this preanalysis. There is no
1758 -- point in processing them now, since they will be applied properly
1759 -- and in the proper location when the default expressions reanalyzed
1760 -- and reexpanded later on. We will also have more information at that
1761 -- point for possible suppression of individual checks.
1115dd7e 1762
06b599fd
YM		 1763 -- However, in SPARK mode, most expansion is suppressed, and this
1764 -- later reanalysis and reexpansion may not occur. SPARK mode does
a7f1b24f 1765 -- require the setting of checking flags for proof purposes, so we
06b599fd 1766 -- do the SPARK preanalysis without suppressing checks.
a7f1b24f 1767
06b599fd 1768 -- This special handling for SPARK mode is required for example in the
a7f1b24f
RD		 1769 -- case of Ada 2012 constructs such as quantified expressions, which are
1770 -- expanded in two separate steps.
996ae0b0 1771
f5da7a97 1772 if GNATprove_Mode then
1115dd7e 1773 Analyze_And_Resolve (N, T);
1115dd7e
ES		 1774 else
1775 Analyze_And_Resolve (N, T, Suppress => All_Checks);
1776 end if;
996ae0b0
RK		 1777
1778 Expander_Mode_Restore;
1779 Full_Analysis := Save_Full_Analysis;
45fc7ddb 1780 end Preanalyze_And_Resolve;
996ae0b0 1781
a77842bd 1782 -- Version without context type
996ae0b0 1783
45fc7ddb 1784 procedure Preanalyze_And_Resolve (N : Node_Id) is
996ae0b0
RK		 1785 Save_Full_Analysis : constant Boolean := Full_Analysis;
1786
1787 begin
1788 Full_Analysis := False;
1789 Expander_Mode_Save_And_Set (False);
1790
1791 Analyze (N);
1792 Resolve (N, Etype (N), Suppress => All_Checks);
1793
1794 Expander_Mode_Restore;
1795 Full_Analysis := Save_Full_Analysis;
45fc7ddb 1796 end Preanalyze_And_Resolve;
996ae0b0
RK		 1797
1798 ----------------------------------
1799 -- Replace_Actual_Discriminants --
1800 ----------------------------------
1801
1802 procedure Replace_Actual_Discriminants (N : Node_Id; Default : Node_Id) is
1803 Loc : constant Source_Ptr := Sloc (N);
1804 Tsk : Node_Id := Empty;
1805
1806 function Process_Discr (Nod : Node_Id) return Traverse_Result;
e0296583 1807 -- Comment needed???
996ae0b0
RK		 1808
1809 -------------------
1810 -- Process_Discr --
1811 -------------------
1812
1813 function Process_Discr (Nod : Node_Id) return Traverse_Result is
1814 Ent : Entity_Id;
1815
1816 begin
1817 if Nkind (Nod) = N_Identifier then
1818 Ent := Entity (Nod);
1819
1820 if Present (Ent)
1821 and then Ekind (Ent) = E_Discriminant
1822 then
1823 Rewrite (Nod,
1824 Make_Selected_Component (Loc,
1825 Prefix => New_Copy_Tree (Tsk, New_Sloc => Loc),
1826 Selector_Name => Make_Identifier (Loc, Chars (Ent))));
1827
1828 Set_Etype (Nod, Etype (Ent));
1829 end if;
1830
1831 end if;
1832
1833 return OK;
1834 end Process_Discr;
1835
1836 procedure Replace_Discrs is new Traverse_Proc (Process_Discr);
1837
1838 -- Start of processing for Replace_Actual_Discriminants
1839
1840 begin
4460a9bc 1841 if not Expander_Active then
996ae0b0
RK		 1842 return;
1843 end if;
1844
1845 if Nkind (Name (N)) = N_Selected_Component then
1846 Tsk := Prefix (Name (N));
1847
1848 elsif Nkind (Name (N)) = N_Indexed_Component then
1849 Tsk := Prefix (Prefix (Name (N)));
1850 end if;
1851
1852 if No (Tsk) then
1853 return;
1854 else
1855 Replace_Discrs (Default);
1856 end if;
1857 end Replace_Actual_Discriminants;
1858
1859 -------------
1860 -- Resolve --
1861 -------------
1862
1863 procedure Resolve (N : Node_Id; Typ : Entity_Id) is
dae2b8ea
HK		 1864 Ambiguous : Boolean := False;
1865 Ctx_Type : Entity_Id := Typ;
1866 Expr_Type : Entity_Id := Empty; -- prevent junk warning
1867 Err_Type : Entity_Id := Empty;
1868 Found : Boolean := False;
1869 From_Lib : Boolean;
996ae0b0 1870 I : Interp_Index;
dae2b8ea 1871 I1 : Interp_Index := 0; -- prevent junk warning
996ae0b0
RK		 1872 It : Interp;
1873 It1 : Interp;
996ae0b0 1874 Seen : Entity_Id := Empty; -- prevent junk warning
dae2b8ea
HK		 1875
1876 function Comes_From_Predefined_Lib_Unit (Nod : Node_Id) return Boolean;
1877 -- Determine whether a node comes from a predefined library unit or
1878 -- Standard.
996ae0b0
RK		 1879
1880 procedure Patch_Up_Value (N : Node_Id; Typ : Entity_Id);
1881 -- Try and fix up a literal so that it matches its expected type. New
1882 -- literals are manufactured if necessary to avoid cascaded errors.
1883
7415029d
AC		 1884 procedure Report_Ambiguous_Argument;
1885 -- Additional diagnostics when an ambiguous call has an ambiguous
1886 -- argument (typically a controlling actual).
1887
996ae0b0
RK		 1888 procedure Resolution_Failed;
1889 -- Called when attempt at resolving current expression fails
1890
dae2b8ea
HK		 1891 ------------------------------------
1892 -- Comes_From_Predefined_Lib_Unit --
1893 -------------------------------------
1894
1895 function Comes_From_Predefined_Lib_Unit (Nod : Node_Id) return Boolean is
1896 begin
1897 return
1898 Sloc (Nod) = Standard_Location
5cc9353d
RD		 1899 or else Is_Predefined_File_Name
1900 (Unit_File_Name (Get_Source_Unit (Sloc (Nod))));
dae2b8ea
HK		 1901 end Comes_From_Predefined_Lib_Unit;
1902
996ae0b0
RK		 1903 --------------------
1904 -- Patch_Up_Value --
1905 --------------------
1906
1907 procedure Patch_Up_Value (N : Node_Id; Typ : Entity_Id) is
1908 begin
e0296583 1909 if Nkind (N) = N_Integer_Literal and then Is_Real_Type (Typ) then
996ae0b0
RK		 1910 Rewrite (N,
1911 Make_Real_Literal (Sloc (N),
1912 Realval => UR_From_Uint (Intval (N))));
1913 Set_Etype (N, Universal_Real);
1914 Set_Is_Static_Expression (N);
1915
e0296583 1916 elsif Nkind (N) = N_Real_Literal and then Is_Integer_Type (Typ) then
996ae0b0
RK		 1917 Rewrite (N,
1918 Make_Integer_Literal (Sloc (N),
1919 Intval => UR_To_Uint (Realval (N))));
1920 Set_Etype (N, Universal_Integer);
1921 Set_Is_Static_Expression (N);
45fc7ddb 1922
996ae0b0 1923 elsif Nkind (N) = N_String_Literal
e0296583 1924 and then Is_Character_Type (Typ)
996ae0b0
RK		 1925 then
1926 Set_Character_Literal_Name (Char_Code (Character'Pos ('A')));
1927 Rewrite (N,
1928 Make_Character_Literal (Sloc (N),
1929 Chars => Name_Find,
82c80734
RD		 1930 Char_Literal_Value =>
1931 UI_From_Int (Character'Pos ('A'))));
996ae0b0
RK		 1932 Set_Etype (N, Any_Character);
1933 Set_Is_Static_Expression (N);
1934
e0296583 1935 elsif Nkind (N) /= N_String_Literal and then Is_String_Type (Typ) then
996ae0b0
RK		 1936 Rewrite (N,
1937 Make_String_Literal (Sloc (N),
1938 Strval => End_String));
1939
1940 elsif Nkind (N) = N_Range then
e0296583 1941 Patch_Up_Value (Low_Bound (N), Typ);
996ae0b0
RK		 1942 Patch_Up_Value (High_Bound (N), Typ);
1943 end if;
1944 end Patch_Up_Value;
1945
7415029d
AC		 1946 -------------------------------
1947 -- Report_Ambiguous_Argument --
1948 -------------------------------
1949
1950 procedure Report_Ambiguous_Argument is
1951 Arg : constant Node_Id := First (Parameter_Associations (N));
1952 I : Interp_Index;
1953 It : Interp;
1954
1955 begin
1956 if Nkind (Arg) = N_Function_Call
1957 and then Is_Entity_Name (Name (Arg))
1958 and then Is_Overloaded (Name (Arg))
1959 then
ed2233dc 1960 Error_Msg_NE ("ambiguous call to&", Arg, Name (Arg));
7415029d 1961
e0296583 1962 -- Could use comments on what is going on here???
bfc07071 1963
7415029d
AC		 1964 Get_First_Interp (Name (Arg), I, It);
1965 while Present (It.Nam) loop
1966 Error_Msg_Sloc := Sloc (It.Nam);
1967
1968 if Nkind (Parent (It.Nam)) = N_Full_Type_Declaration then
ed2233dc 1969 Error_Msg_N ("interpretation (inherited) #!", Arg);
7415029d 1970 else
ed2233dc 1971 Error_Msg_N ("interpretation #!", Arg);
7415029d
AC		 1972 end if;
1973
1974 Get_Next_Interp (I, It);
1975 end loop;
1976 end if;
1977 end Report_Ambiguous_Argument;
1978
996ae0b0
RK		 1979 -----------------------
1980 -- Resolution_Failed --
1981 -----------------------
1982
1983 procedure Resolution_Failed is
1984 begin
1985 Patch_Up_Value (N, Typ);
405b907c
AC		 1986
1987 -- Set the type to the desired one to minimize cascaded errors. Note
1988 -- that this is an approximation and does not work in all cases.
1989
996ae0b0 1990 Set_Etype (N, Typ);
405b907c 1991
996ae0b0
RK		 1992 Debug_A_Exit ("resolving ", N, " (done, resolution failed)");
1993 Set_Is_Overloaded (N, False);
1994
1995 -- The caller will return without calling the expander, so we need
1996 -- to set the analyzed flag. Note that it is fine to set Analyzed
1997 -- to True even if we are in the middle of a shallow analysis,
1998 -- (see the spec of sem for more details) since this is an error
1999 -- situation anyway, and there is no point in repeating the
2000 -- analysis later (indeed it won't work to repeat it later, since
2001 -- we haven't got a clear resolution of which entity is being
2002 -- referenced.)
2003
2004 Set_Analyzed (N, True);
2005 return;
2006 end Resolution_Failed;
2007
2008 -- Start of processing for Resolve
2009
2010 begin
5c736541
RD		 2011 if N = Error then
2012 return;
2013 end if;
2014
e0296583
AC		 2015 -- Access attribute on remote subprogram cannot be used for a non-remote
2016 -- access-to-subprogram type.
996ae0b0
RK		 2017
2018 if Nkind (N) = N_Attribute_Reference
b69cd36a
AC		 2019 and then Nam_In (Attribute_Name (N), Name_Access,
2020 Name_Unrestricted_Access,
2021 Name_Unchecked_Access)
996ae0b0
RK		 2022 and then Comes_From_Source (N)
2023 and then Is_Entity_Name (Prefix (N))
2024 and then Is_Subprogram (Entity (Prefix (N)))
2025 and then Is_Remote_Call_Interface (Entity (Prefix (N)))
2026 and then not Is_Remote_Access_To_Subprogram_Type (Typ)
2027 then
2028 Error_Msg_N
2029 ("prefix must statically denote a non-remote subprogram", N);
2030 end if;
2031
dae2b8ea
HK		 2032 From_Lib := Comes_From_Predefined_Lib_Unit (N);
2033
996ae0b0
RK		 2034 -- If the context is a Remote_Access_To_Subprogram, access attributes
2035 -- must be resolved with the corresponding fat pointer. There is no need
2036 -- to check for the attribute name since the return type of an
2037 -- attribute is never a remote type.
2038
2039 if Nkind (N) = N_Attribute_Reference
2040 and then Comes_From_Source (N)
19fb051c 2041 and then (Is_Remote_Call_Interface (Typ) or else Is_Remote_Types (Typ))
996ae0b0
RK		 2042 then
2043 declare
2044 Attr : constant Attribute_Id :=
2045 Get_Attribute_Id (Attribute_Name (N));
2046 Pref : constant Node_Id := Prefix (N);
2047 Decl : Node_Id;
2048 Spec : Node_Id;
2049 Is_Remote : Boolean := True;
2050
2051 begin
a77842bd 2052 -- Check that Typ is a remote access-to-subprogram type
996ae0b0 2053
a77842bd 2054 if Is_Remote_Access_To_Subprogram_Type (Typ) then
955871d3 2055
996ae0b0
RK		 2056 -- Prefix (N) must statically denote a remote subprogram
2057 -- declared in a package specification.
2058
799d0e05
AC		 2059 if Attr = Attribute_Access or else
2060 Attr = Attribute_Unchecked_Access or else
2061 Attr = Attribute_Unrestricted_Access
2062 then
996ae0b0
RK		 2063 Decl := Unit_Declaration_Node (Entity (Pref));
2064
2065 if Nkind (Decl) = N_Subprogram_Body then
2066 Spec := Corresponding_Spec (Decl);
2067
b8e6830b 2068 if Present (Spec) then
996ae0b0
RK		 2069 Decl := Unit_Declaration_Node (Spec);
2070 end if;
2071 end if;
2072
2073 Spec := Parent (Decl);
2074
2075 if not Is_Entity_Name (Prefix (N))
2076 or else Nkind (Spec) /= N_Package_Specification
2077 or else
2078 not Is_Remote_Call_Interface (Defining_Entity (Spec))
2079 then
2080 Is_Remote := False;
2081 Error_Msg_N
2082 ("prefix must statically denote a remote subprogram ",
2083 N);
2084 end if;
996ae0b0 2085
799d0e05
AC		 2086 -- If we are generating code in distributed mode, perform
2087 -- semantic checks against corresponding remote entities.
fbf5a39b 2088
4460a9bc 2089 if Expander_Active
799d0e05
AC		 2090 and then Get_PCS_Name /= Name_No_DSA
2091 then
2092 Check_Subtype_Conformant
2093 (New_Id => Entity (Prefix (N)),
2094 Old_Id => Designated_Type
2095 (Corresponding_Remote_Type (Typ)),
2096 Err_Loc => N);
2097
2098 if Is_Remote then
2099 Process_Remote_AST_Attribute (N, Typ);
2100 end if;
996ae0b0
RK		 2101 end if;
2102 end if;
2103 end if;
2104 end;
2105 end if;
2106
2107 Debug_A_Entry ("resolving ", N);
fe58fea7 2108
ee1a7572
AC		 2109 if Debug_Flag_V then
2110 Write_Overloads (N);
2111 end if;
996ae0b0 2112
07fc65c4
GB		 2113 if Comes_From_Source (N) then
2114 if Is_Fixed_Point_Type (Typ) then
2115 Check_Restriction (No_Fixed_Point, N);
996ae0b0 2116
07fc65c4
GB		 2117 elsif Is_Floating_Point_Type (Typ)
2118 and then Typ /= Universal_Real
2119 and then Typ /= Any_Real
2120 then
2121 Check_Restriction (No_Floating_Point, N);
2122 end if;
996ae0b0
RK		 2123 end if;
2124
2125 -- Return if already analyzed
2126
2127 if Analyzed (N) then
2128 Debug_A_Exit ("resolving ", N, " (done, already analyzed)");
dec6faf1 2129 Analyze_Dimension (N);
996ae0b0
RK		 2130 return;
2131
3e586e10
AC		 2132 -- Any case of Any_Type as the Etype value means that we had a
2133 -- previous error.
1486a00e
AC		 2134
2135 elsif Etype (N) = Any_Type then
996ae0b0
RK		 2136 Debug_A_Exit ("resolving ", N, " (done, Etype = Any_Type)");
2137 return;
2138 end if;
2139
2140 Check_Parameterless_Call (N);
2141
064f4527
TQ		 2142 -- The resolution of an Expression_With_Actions is determined by
2143 -- its Expression.
2144
2145 if Nkind (N) = N_Expression_With_Actions then
2146 Resolve (Expression (N), Typ);
2147
2148 Found := True;
2149 Expr_Type := Etype (Expression (N));
2150
996ae0b0
RK		 2151 -- If not overloaded, then we know the type, and all that needs doing
2152 -- is to check that this type is compatible with the context.
2153
064f4527 2154 elsif not Is_Overloaded (N) then
996ae0b0
RK		 2155 Found := Covers (Typ, Etype (N));
2156 Expr_Type := Etype (N);
2157
2158 -- In the overloaded case, we must select the interpretation that
2159 -- is compatible with the context (i.e. the type passed to Resolve)
2160
2161 else
996ae0b0
RK		 2162 -- Loop through possible interpretations
2163
1420b484 2164 Get_First_Interp (N, I, It);
996ae0b0 2165 Interp_Loop : while Present (It.Typ) loop
ee1a7572
AC		 2166 if Debug_Flag_V then
2167 Write_Str ("Interp: ");
2168 Write_Interp (It);
2169 end if;
2170
996ae0b0 2171 -- We are only interested in interpretations that are compatible
aa5147f0 2172 -- with the expected type, any other interpretations are ignored.
996ae0b0 2173
fbf5a39b
AC		 2174 if not Covers (Typ, It.Typ) then
2175 if Debug_Flag_V then
2176 Write_Str (" interpretation incompatible with context");
2177 Write_Eol;
2178 end if;
996ae0b0 2179
fbf5a39b 2180 else
aa5147f0
ES		 2181 -- Skip the current interpretation if it is disabled by an
2182 -- abstract operator. This action is performed only when the
2183 -- type against which we are resolving is the same as the
2184 -- type of the interpretation.
2185
0791fbe9 2186 if Ada_Version >= Ada_2005
aa5147f0
ES		 2187 and then It.Typ = Typ
2188 and then Typ /= Universal_Integer
2189 and then Typ /= Universal_Real
2190 and then Present (It.Abstract_Op)
2191 then
ee1a7572
AC		 2192 if Debug_Flag_V then
2193 Write_Line ("Skip.");
2194 end if;
2195
aa5147f0
ES		 2196 goto Continue;
2197 end if;
2198
996ae0b0
RK		 2199 -- First matching interpretation
2200
2201 if not Found then
2202 Found := True;
2203 I1 := I;
2204 Seen := It.Nam;
2205 Expr_Type := It.Typ;
2206
fbf5a39b 2207 -- Matching interpretation that is not the first, maybe an
996ae0b0
RK		 2208 -- error, but there are some cases where preference rules are
2209 -- used to choose between the two possibilities. These and
2210 -- some more obscure cases are handled in Disambiguate.
2211
2212 else
90b51aaf
AC		 2213 -- If the current statement is part of a predefined library
2214 -- unit, then all interpretations which come from user level
2215 -- packages should not be considered. Check previous and
2216 -- current one.
2217
2218 if From_Lib then
2219 if not Comes_From_Predefined_Lib_Unit (It.Nam) then
2220 goto Continue;
2221
2222 elsif not Comes_From_Predefined_Lib_Unit (Seen) then
2223
c2e54001 2224 -- Previous interpretation must be discarded
90b51aaf 2225
c2e54001
AC		 2226 I1 := I;
2227 Seen := It.Nam;
90b51aaf
AC		 2228 Expr_Type := It.Typ;
2229 Set_Entity (N, Seen);
2230 goto Continue;
2231 end if;
dae2b8ea
HK		 2232 end if;
2233
c2e54001 2234 -- Otherwise apply further disambiguation steps
90b51aaf 2235
996ae0b0
RK		 2236 Error_Msg_Sloc := Sloc (Seen);
2237 It1 := Disambiguate (N, I1, I, Typ);
2238
fbf5a39b
AC		 2239 -- Disambiguation has succeeded. Skip the remaining
2240 -- interpretations.
996ae0b0 2241
fbf5a39b
AC		 2242 if It1 /= No_Interp then
2243 Seen := It1.Nam;
2244 Expr_Type := It1.Typ;
2245
2246 while Present (It.Typ) loop
2247 Get_Next_Interp (I, It);
2248 end loop;
2249
2250 else
0310af44
AC		 2251 -- Before we issue an ambiguity complaint, check for the
2252 -- case of a subprogram call where at least one of the
2253 -- arguments is Any_Type, and if so suppress the message,
2254 -- since it is a cascaded error. This can also happen for
2255 -- a generalized indexing operation.
2256
2257 if Nkind (N) in N_Subprogram_Call
2258 or else (Nkind (N) = N_Indexed_Component
2259 and then Present (Generalized_Indexing (N)))
2260 then
996ae0b0 2261 declare
1420b484 2262 A : Node_Id;
996ae0b0
RK		 2263 E : Node_Id;
2264
2265 begin
0310af44
AC		 2266 if Nkind (N) = N_Indexed_Component then
2267 Rewrite (N, Generalized_Indexing (N));
2268 end if;
2269
1420b484 2270 A := First_Actual (N);
996ae0b0
RK		 2271 while Present (A) loop
2272 E := A;
2273
2274 if Nkind (E) = N_Parameter_Association then
2275 E := Explicit_Actual_Parameter (E);
2276 end if;
2277
2278 if Etype (E) = Any_Type then
2279 if Debug_Flag_V then
2280 Write_Str ("Any_Type in call");
2281 Write_Eol;
2282 end if;
2283
2284 exit Interp_Loop;
2285 end if;
2286
2287 Next_Actual (A);
2288 end loop;
2289 end;
2290
aa5147f0 2291 elsif Nkind (N) in N_Binary_Op
996ae0b0
RK		 2292 and then (Etype (Left_Opnd (N)) = Any_Type
2293 or else Etype (Right_Opnd (N)) = Any_Type)
2294 then
2295 exit Interp_Loop;
2296
21d7ef70 2297 elsif Nkind (N) in N_Unary_Op
996ae0b0
RK		 2298 and then Etype (Right_Opnd (N)) = Any_Type
2299 then
2300 exit Interp_Loop;
2301 end if;
2302
0310af44
AC		 2303 -- Not that special case, so issue message using the flag
2304 -- Ambiguous to control printing of the header message
2305 -- only at the start of an ambiguous set.
996ae0b0
RK		 2306
2307 if not Ambiguous then
aa180613
RD		 2308 if Nkind (N) = N_Function_Call
2309 and then Nkind (Name (N)) = N_Explicit_Dereference
2310 then
ed2233dc 2311 Error_Msg_N
0310af44
AC		 2312 ("ambiguous expression (cannot resolve indirect "
2313 & "call)!", N);
aa180613 2314 else
483c78cb 2315 Error_Msg_NE -- CODEFIX
aa180613
RD		 2316 ("ambiguous expression (cannot resolve&)!",
2317 N, It.Nam);
2318 end if;
fbf5a39b 2319
996ae0b0 2320 Ambiguous := True;
0669bebe
GB		 2321
2322 if Nkind (Parent (Seen)) = N_Full_Type_Declaration then
ed2233dc 2323 Error_Msg_N
0669bebe
GB		 2324 ("\\possible interpretation (inherited)#!", N);
2325 else
4e7a4f6e
AC		 2326 Error_Msg_N -- CODEFIX
2327 ("\\possible interpretation#!", N);
0669bebe 2328 end if;
7415029d 2329
d3b00ce3 2330 if Nkind (N) in N_Subprogram_Call
7415029d
AC		 2331 and then Present (Parameter_Associations (N))
2332 then
2333 Report_Ambiguous_Argument;
2334 end if;
996ae0b0
RK		 2335 end if;
2336
2337 Error_Msg_Sloc := Sloc (It.Nam);
996ae0b0 2338
fbf5a39b 2339 -- By default, the error message refers to the candidate
0669bebe
GB		 2340 -- interpretation. But if it is a predefined operator, it
2341 -- is implicitly declared at the declaration of the type
2342 -- of the operand. Recover the sloc of that declaration
2343 -- for the error message.
fbf5a39b
AC		 2344
2345 if Nkind (N) in N_Op
2346 and then Scope (It.Nam) = Standard_Standard
2347 and then not Is_Overloaded (Right_Opnd (N))
0669bebe
GB		 2348 and then Scope (Base_Type (Etype (Right_Opnd (N)))) /=
2349 Standard_Standard
fbf5a39b
AC		 2350 then
2351 Err_Type := First_Subtype (Etype (Right_Opnd (N)));
2352
2353 if Comes_From_Source (Err_Type)
2354 and then Present (Parent (Err_Type))
2355 then
2356 Error_Msg_Sloc := Sloc (Parent (Err_Type));
2357 end if;
2358
2359 elsif Nkind (N) in N_Binary_Op
2360 and then Scope (It.Nam) = Standard_Standard
2361 and then not Is_Overloaded (Left_Opnd (N))
0669bebe
GB		 2362 and then Scope (Base_Type (Etype (Left_Opnd (N)))) /=
2363 Standard_Standard
fbf5a39b
AC		 2364 then
2365 Err_Type := First_Subtype (Etype (Left_Opnd (N)));
2366
2367 if Comes_From_Source (Err_Type)
2368 and then Present (Parent (Err_Type))
2369 then
2370 Error_Msg_Sloc := Sloc (Parent (Err_Type));
2371 end if;
aa180613
RD		 2372
2373 -- If this is an indirect call, use the subprogram_type
5cc9353d
RD		 2374 -- in the message, to have a meaningful location. Also
2375 -- indicate if this is an inherited operation, created
2376 -- by a type declaration.
aa180613
RD		 2377
2378 elsif Nkind (N) = N_Function_Call
2379 and then Nkind (Name (N)) = N_Explicit_Dereference
2380 and then Is_Type (It.Nam)
2381 then
2382 Err_Type := It.Nam;
2383 Error_Msg_Sloc :=
2384 Sloc (Associated_Node_For_Itype (Err_Type));
fbf5a39b
AC		 2385 else
2386 Err_Type := Empty;
2387 end if;
2388
2389 if Nkind (N) in N_Op
2390 and then Scope (It.Nam) = Standard_Standard
2391 and then Present (Err_Type)
2392 then
aa5147f0
ES		 2393 -- Special-case the message for universal_fixed
2394 -- operators, which are not declared with the type
2395 -- of the operand, but appear forever in Standard.
2396
9fe696a3 2397 if It.Typ = Universal_Fixed
aa5147f0
ES		 2398 and then Scope (It.Nam) = Standard_Standard
2399 then
ed2233dc 2400 Error_Msg_N
1486a00e
AC		 2401 ("\\possible interpretation as universal_fixed "
2402 & "operation (RM 4.5.5 (19))", N);
aa5147f0 2403 else
ed2233dc 2404 Error_Msg_N
aa5147f0
ES		 2405 ("\\possible interpretation (predefined)#!", N);
2406 end if;
aa180613
RD		 2407
2408 elsif
2409 Nkind (Parent (It.Nam)) = N_Full_Type_Declaration
2410 then
ed2233dc 2411 Error_Msg_N
aa180613 2412 ("\\possible interpretation (inherited)#!", N);
fbf5a39b 2413 else
4e7a4f6e
AC		 2414 Error_Msg_N -- CODEFIX
2415 ("\\possible interpretation#!", N);
fbf5a39b 2416 end if;
996ae0b0 2417
996ae0b0
RK		 2418 end if;
2419 end if;
2420
0669bebe
GB		 2421 -- We have a matching interpretation, Expr_Type is the type
2422 -- from this interpretation, and Seen is the entity.
996ae0b0 2423
0669bebe
GB		 2424 -- For an operator, just set the entity name. The type will be
2425 -- set by the specific operator resolution routine.
996ae0b0
RK		 2426
2427 if Nkind (N) in N_Op then
2428 Set_Entity (N, Seen);
2429 Generate_Reference (Seen, N);
2430
19d846a0
RD		 2431 elsif Nkind (N) = N_Case_Expression then
2432 Set_Etype (N, Expr_Type);
2433
996ae0b0
RK		 2434 elsif Nkind (N) = N_Character_Literal then
2435 Set_Etype (N, Expr_Type);
2436
9b16cb57 2437 elsif Nkind (N) = N_If_Expression then
e0ba1bfd
ES		 2438 Set_Etype (N, Expr_Type);
2439
dedac3eb
RD		 2440 -- AI05-0139-2: Expression is overloaded because type has
2441 -- implicit dereference. If type matches context, no implicit
2442 -- dereference is involved.
44a10091
AC		 2443
2444 elsif Has_Implicit_Dereference (Expr_Type) then
2445 Set_Etype (N, Expr_Type);
2446 Set_Is_Overloaded (N, False);
2447 exit Interp_Loop;
2448
2449 elsif Is_Overloaded (N)
2450 and then Present (It.Nam)
2451 and then Ekind (It.Nam) = E_Discriminant
2452 and then Has_Implicit_Dereference (It.Nam)
2453 then
5f50020a
ES		 2454 -- If the node is a general indexing, the dereference is
2455 -- is inserted when resolving the rewritten form, else
2456 -- insert it now.
2457
2458 if Nkind (N) /= N_Indexed_Component
2459 or else No (Generalized_Indexing (N))
2460 then
2461 Build_Explicit_Dereference (N, It.Nam);
2462 end if;
44a10091 2463
996ae0b0 2464 -- For an explicit dereference, attribute reference, range,
0669bebe
GB		 2465 -- short-circuit form (which is not an operator node), or call
2466 -- with a name that is an explicit dereference, there is
2467 -- nothing to be done at this point.
996ae0b0 2468
4f324de2 2469 elsif Nkind_In (N, N_Attribute_Reference,
45fc7ddb 2470 N_And_Then,
4f324de2 2471 N_Explicit_Dereference,
f4ef7b06 2472 N_Identifier,
4f324de2 2473 N_Indexed_Component,
45fc7ddb
HK		 2474 N_Or_Else,
2475 N_Range,
2476 N_Selected_Component,
2477 N_Slice)
996ae0b0
RK		 2478 or else Nkind (Name (N)) = N_Explicit_Dereference
2479 then
2480 null;
2481
0669bebe 2482 -- For procedure or function calls, set the type of the name,
4519314c 2483 -- and also the entity pointer for the prefix.
996ae0b0 2484
d3b00ce3 2485 elsif Nkind (N) in N_Subprogram_Call
a3f2babd 2486 and then Is_Entity_Name (Name (N))
996ae0b0
RK		 2487 then
2488 Set_Etype (Name (N), Expr_Type);
2489 Set_Entity (Name (N), Seen);
2490 Generate_Reference (Seen, Name (N));
2491
2492 elsif Nkind (N) = N_Function_Call
2493 and then Nkind (Name (N)) = N_Selected_Component
2494 then
2495 Set_Etype (Name (N), Expr_Type);
2496 Set_Entity (Selector_Name (Name (N)), Seen);
2497 Generate_Reference (Seen, Selector_Name (Name (N)));
2498
2499 -- For all other cases, just set the type of the Name
2500
2501 else
2502 Set_Etype (Name (N), Expr_Type);
2503 end if;
2504
996ae0b0
RK		 2505 end if;
2506
aa5147f0
ES		 2507 <<Continue>>
2508
996ae0b0
RK		 2509 -- Move to next interpretation
2510
c8ef728f 2511 exit Interp_Loop when No (It.Typ);
996ae0b0
RK		 2512
2513 Get_Next_Interp (I, It);
2514 end loop Interp_Loop;
2515 end if;
2516
2517 -- At this stage Found indicates whether or not an acceptable
4519314c
AC		 2518 -- interpretation exists. If not, then we have an error, except that if
2519 -- the context is Any_Type as a result of some other error, then we
2520 -- suppress the error report.
996ae0b0
RK		 2521
2522 if not Found then
2523 if Typ /= Any_Type then
2524
0669bebe
GB		 2525 -- If type we are looking for is Void, then this is the procedure
2526 -- call case, and the error is simply that what we gave is not a
2527 -- procedure name (we think of procedure calls as expressions with
159a5104 2528 -- types internally, but the user doesn't think of them this way).
996ae0b0
RK		 2529
2530 if Typ = Standard_Void_Type then
91b1417d
AC		 2531
2532 -- Special case message if function used as a procedure
2533
2534 if Nkind (N) = N_Procedure_Call_Statement
2535 and then Is_Entity_Name (Name (N))
2536 and then Ekind (Entity (Name (N))) = E_Function
2537 then
2538 Error_Msg_NE
2539 ("cannot use function & in a procedure call",
2540 Name (N), Entity (Name (N)));
2541
0669bebe 2542 -- Otherwise give general message (not clear what cases this
a90bd866 2543 -- covers, but no harm in providing for them).
91b1417d
AC		 2544
2545 else
2546 Error_Msg_N ("expect procedure name in procedure call", N);
2547 end if;
2548
996ae0b0
RK		 2549 Found := True;
2550
2551 -- Otherwise we do have a subexpression with the wrong type
2552
0669bebe
GB		 2553 -- Check for the case of an allocator which uses an access type
2554 -- instead of the designated type. This is a common error and we
2555 -- specialize the message, posting an error on the operand of the
2556 -- allocator, complaining that we expected the designated type of
2557 -- the allocator.
996ae0b0
RK		 2558
2559 elsif Nkind (N) = N_Allocator
3f1bc2cf
AC		 2560 and then Is_Access_Type (Typ)
2561 and then Is_Access_Type (Etype (N))
996ae0b0
RK		 2562 and then Designated_Type (Etype (N)) = Typ
2563 then
2564 Wrong_Type (Expression (N), Designated_Type (Typ));
2565 Found := True;
2566
0669bebe
GB		 2567 -- Check for view mismatch on Null in instances, for which the
2568 -- view-swapping mechanism has no identifier.
17be0cdf
ES		 2569
2570 elsif (In_Instance or else In_Inlined_Body)
2571 and then (Nkind (N) = N_Null)
2572 and then Is_Private_Type (Typ)
2573 and then Is_Access_Type (Full_View (Typ))
2574 then
2575 Resolve (N, Full_View (Typ));
2576 Set_Etype (N, Typ);
2577 return;
2578
aa180613
RD		 2579 -- Check for an aggregate. Sometimes we can get bogus aggregates
2580 -- from misuse of parentheses, and we are about to complain about
2581 -- the aggregate without even looking inside it.
996ae0b0 2582
aa180613
RD		 2583 -- Instead, if we have an aggregate of type Any_Composite, then
2584 -- analyze and resolve the component fields, and then only issue
2585 -- another message if we get no errors doing this (otherwise
2586 -- assume that the errors in the aggregate caused the problem).
996ae0b0
RK		 2587
2588 elsif Nkind (N) = N_Aggregate
2589 and then Etype (N) = Any_Composite
2590 then
996ae0b0
RK		 2591 -- Disable expansion in any case. If there is a type mismatch
2592 -- it may be fatal to try to expand the aggregate. The flag
2593 -- would otherwise be set to false when the error is posted.
2594
2595 Expander_Active := False;
2596
2597 declare
2598 procedure Check_Aggr (Aggr : Node_Id);
aa180613
RD		 2599 -- Check one aggregate, and set Found to True if we have a
2600 -- definite error in any of its elements
996ae0b0
RK		 2601
2602 procedure Check_Elmt (Aelmt : Node_Id);
aa180613
RD		 2603 -- Check one element of aggregate and set Found to True if
2604 -- we definitely have an error in the element.
2605
2606 ----------------
2607 -- Check_Aggr --
2608 ----------------
996ae0b0
RK		 2609
2610 procedure Check_Aggr (Aggr : Node_Id) is
2611 Elmt : Node_Id;
2612
2613 begin
2614 if Present (Expressions (Aggr)) then
2615 Elmt := First (Expressions (Aggr));
2616 while Present (Elmt) loop
2617 Check_Elmt (Elmt);
2618 Next (Elmt);
2619 end loop;
2620 end if;
2621
2622 if Present (Component_Associations (Aggr)) then
2623 Elmt := First (Component_Associations (Aggr));
2624 while Present (Elmt) loop
aa180613 2625
0669bebe
GB		 2626 -- If this is a default-initialized component, then
2627 -- there is nothing to check. The box will be
2628 -- replaced by the appropriate call during late
2629 -- expansion.
aa180613 2630
f4ef7b06
AC		 2631 if Nkind (Elmt) /= N_Iterated_Component_Association
2632 and then not Box_Present (Elmt)
2633 then
aa180613
RD		 2634 Check_Elmt (Expression (Elmt));
2635 end if;
2636
996ae0b0
RK		 2637 Next (Elmt);
2638 end loop;
2639 end if;
2640 end Check_Aggr;
2641
fbf5a39b
AC		 2642 ----------------
2643 -- Check_Elmt --
2644 ----------------
2645
996ae0b0
RK		 2646 procedure Check_Elmt (Aelmt : Node_Id) is
2647 begin
2648 -- If we have a nested aggregate, go inside it (to
5cc9353d
RD		 2649 -- attempt a naked analyze-resolve of the aggregate can
2650 -- cause undesirable cascaded errors). Do not resolve
2651 -- expression if it needs a type from context, as for
2652 -- integer * fixed expression.
996ae0b0
RK		 2653
2654 if Nkind (Aelmt) = N_Aggregate then
2655 Check_Aggr (Aelmt);
2656
2657 else
2658 Analyze (Aelmt);
2659
2660 if not Is_Overloaded (Aelmt)
2661 and then Etype (Aelmt) /= Any_Fixed
2662 then
fbf5a39b 2663 Resolve (Aelmt);
996ae0b0
RK		 2664 end if;
2665
2666 if Etype (Aelmt) = Any_Type then
2667 Found := True;
2668 end if;
2669 end if;
2670 end Check_Elmt;
2671
2672 begin
2673 Check_Aggr (N);
2674 end;
2675 end if;
2676
6fd0a72a
AC		 2677 -- Looks like we have a type error, but check for special case
2678 -- of Address wanted, integer found, with the configuration pragma
2679 -- Allow_Integer_Address active. If we have this case, introduce
2680 -- an unchecked conversion to allow the integer expression to be
2681 -- treated as an Address. The reverse case of integer wanted,
2682 -- Address found, is treated in an analogous manner.
2683
061828e3
AC		 2684 if Address_Integer_Convert_OK (Typ, Etype (N)) then
2685 Rewrite (N, Unchecked_Convert_To (Typ, Relocate_Node (N)));
2686 Analyze_And_Resolve (N, Typ);
2687 return;
a8a42b93
AC		 2688
2689 -- Under relaxed RM semantics silently replace occurrences of null
3ab53b0d 2690 -- by System.Address_Null.
a8a42b93
AC		 2691
2692 elsif Null_To_Null_Address_Convert_OK (N, Typ) then
2693 Replace_Null_By_Null_Address (N);
2694 Analyze_And_Resolve (N, Typ);
2695 return;
6fd0a72a 2696 end if;
818b578d 2697
3ab53b0d 2698 -- That special Allow_Integer_Address check did not apply, so we
6fd0a72a
AC		 2699 -- have a real type error. If an error message was issued already,
2700 -- Found got reset to True, so if it's still False, issue standard
2701 -- Wrong_Type message.
818b578d 2702
6fd0a72a
AC		 2703 if not Found then
2704 if Is_Overloaded (N) and then Nkind (N) = N_Function_Call then
65356e64
AC		 2705 declare
2706 Subp_Name : Node_Id;
6fd0a72a 2707
65356e64
AC		 2708 begin
2709 if Is_Entity_Name (Name (N)) then
2710 Subp_Name := Name (N);
2711
2712 elsif Nkind (Name (N)) = N_Selected_Component then
2713
a77842bd 2714 -- Protected operation: retrieve operation name
65356e64
AC		 2715
2716 Subp_Name := Selector_Name (Name (N));
19fb051c 2717
65356e64
AC		 2718 else
2719 raise Program_Error;
2720 end if;
2721
2722 Error_Msg_Node_2 := Typ;
1486a00e 2723 Error_Msg_NE
d65a80fd
HK		 2724 ("no visible interpretation of& matches expected type&",
2725 N, Subp_Name);
65356e64 2726 end;
996ae0b0
RK		 2727
2728 if All_Errors_Mode then
2729 declare
2730 Index : Interp_Index;
2731 It : Interp;
2732
2733 begin
aa180613 2734 Error_Msg_N ("\\possible interpretations:", N);
996ae0b0 2735
1420b484 2736 Get_First_Interp (Name (N), Index, It);
996ae0b0 2737 while Present (It.Nam) loop
ea985d95 2738 Error_Msg_Sloc := Sloc (It.Nam);
aa5147f0
ES		 2739 Error_Msg_Node_2 := It.Nam;
2740 Error_Msg_NE
2741 ("\\ type& for & declared#", N, It.Typ);
996ae0b0
RK		 2742 Get_Next_Interp (Index, It);
2743 end loop;
2744 end;
aa5147f0 2745
996ae0b0
RK		 2746 else
2747 Error_Msg_N ("\use -gnatf for details", N);
2748 end if;
19fb051c 2749
996ae0b0
RK		 2750 else
2751 Wrong_Type (N, Typ);
2752 end if;
2753 end if;
2754 end if;
2755
2756 Resolution_Failed;
2757 return;
2758
2759 -- Test if we have more than one interpretation for the context
2760
2761 elsif Ambiguous then
2762 Resolution_Failed;
2763 return;
2764
fe58fea7
AC		 2765 -- Only one intepretation
2766
996ae0b0 2767 else
ee1a7572
AC		 2768 -- In Ada 2005, if we have something like "X : T := 2 + 2;", where
2769 -- the "+" on T is abstract, and the operands are of universal type,
2770 -- the above code will have (incorrectly) resolved the "+" to the
fe58fea7
AC		 2771 -- universal one in Standard. Therefore check for this case and give
2772 -- an error. We can't do this earlier, because it would cause legal
2773 -- cases to get errors (when some other type has an abstract "+").
ee1a7572 2774
36504e5f
AC		 2775 if Ada_Version >= Ada_2005
2776 and then Nkind (N) in N_Op
2777 and then Is_Overloaded (N)
2778 and then Is_Universal_Numeric_Type (Etype (Entity (N)))
ee1a7572
AC		 2779 then
2780 Get_First_Interp (N, I, It);
2781 while Present (It.Typ) loop
2782 if Present (It.Abstract_Op) and then
2783 Etype (It.Abstract_Op) = Typ
2784 then
2785 Error_Msg_NE
2786 ("cannot call abstract subprogram &!", N, It.Abstract_Op);
2787 return;
2788 end if;
2789
2790 Get_Next_Interp (I, It);
2791 end loop;
2792 end if;
2793
2794 -- Here we have an acceptable interpretation for the context
2795
996ae0b0
RK		 2796 -- Propagate type information and normalize tree for various
2797 -- predefined operations. If the context only imposes a class of
2798 -- types, rather than a specific type, propagate the actual type
2799 -- downward.
2800
19fb051c
AC		 2801 if Typ = Any_Integer or else
2802 Typ = Any_Boolean or else
2803 Typ = Any_Modular or else
2804 Typ = Any_Real or else
2805 Typ = Any_Discrete
996ae0b0
RK		 2806 then
2807 Ctx_Type := Expr_Type;
2808
5cc9353d
RD		 2809 -- Any_Fixed is legal in a real context only if a specific fixed-
2810 -- point type is imposed. If Norman Cohen can be confused by this,
2811 -- it deserves a separate message.
996ae0b0
RK		 2812
2813 if Typ = Any_Real
2814 and then Expr_Type = Any_Fixed
2815 then
758c442c 2816 Error_Msg_N ("illegal context for mixed mode operation", N);
996ae0b0
RK		 2817 Set_Etype (N, Universal_Real);
2818 Ctx_Type := Universal_Real;
2819 end if;
2820 end if;
2821
f3d57416 2822 -- A user-defined operator is transformed into a function call at
0ab80019
AC		 2823 -- this point, so that further processing knows that operators are
2824 -- really operators (i.e. are predefined operators). User-defined
2825 -- operators that are intrinsic are just renamings of the predefined
2826 -- ones, and need not be turned into calls either, but if they rename
2827 -- a different operator, we must transform the node accordingly.
2828 -- Instantiations of Unchecked_Conversion are intrinsic but are
2829 -- treated as functions, even if given an operator designator.
2830
2831 if Nkind (N) in N_Op
2832 and then Present (Entity (N))
2833 and then Ekind (Entity (N)) /= E_Operator
2834 then
0ab80019
AC		 2835 if not Is_Predefined_Op (Entity (N)) then
2836 Rewrite_Operator_As_Call (N, Entity (N));
2837
615cbd95
AC		 2838 elsif Present (Alias (Entity (N)))
2839 and then
45fc7ddb
HK		 2840 Nkind (Parent (Parent (Entity (N)))) =
2841 N_Subprogram_Renaming_Declaration
615cbd95 2842 then
0ab80019
AC		 2843 Rewrite_Renamed_Operator (N, Alias (Entity (N)), Typ);
2844
2845 -- If the node is rewritten, it will be fully resolved in
2846 -- Rewrite_Renamed_Operator.
2847
2848 if Analyzed (N) then
2849 return;
2850 end if;
2851 end if;
2852 end if;
2853
996ae0b0 2854 case N_Subexpr'(Nkind (N)) is
d8f43ee6
HK		 2855 when N_Aggregate =>
2856 Resolve_Aggregate (N, Ctx_Type);
996ae0b0 2857
d8f43ee6
HK		 2858 when N_Allocator =>
2859 Resolve_Allocator (N, Ctx_Type);
996ae0b0 2860
d8f43ee6
HK		 2861 when N_Short_Circuit =>
2862 Resolve_Short_Circuit (N, Ctx_Type);
996ae0b0 2863
d8f43ee6
HK		 2864 when N_Attribute_Reference =>
2865 Resolve_Attribute (N, Ctx_Type);
19d846a0 2866
d8f43ee6
HK		 2867 when N_Case_Expression =>
2868 Resolve_Case_Expression (N, Ctx_Type);
996ae0b0 2869
d8f43ee6
HK		 2870 when N_Character_Literal =>
2871 Resolve_Character_Literal (N, Ctx_Type);
996ae0b0 2872
9eb8d5b4
AC		 2873 when N_Delta_Aggregate =>
2874 Resolve_Delta_Aggregate (N, Ctx_Type);
2875
d8f43ee6
HK		 2876 when N_Expanded_Name =>
2877 Resolve_Entity_Name (N, Ctx_Type);
996ae0b0 2878
d8f43ee6
HK		 2879 when N_Explicit_Dereference =>
2880 Resolve_Explicit_Dereference (N, Ctx_Type);
955871d3 2881
d8f43ee6
HK		 2882 when N_Expression_With_Actions =>
2883 Resolve_Expression_With_Actions (N, Ctx_Type);
955871d3 2884
d8f43ee6
HK		 2885 when N_Extension_Aggregate =>
2886 Resolve_Extension_Aggregate (N, Ctx_Type);
996ae0b0 2887
d8f43ee6
HK		 2888 when N_Function_Call =>
2889 Resolve_Call (N, Ctx_Type);
996ae0b0 2890
d8f43ee6
HK		 2891 when N_Identifier =>
2892 Resolve_Entity_Name (N, Ctx_Type);
9b16cb57 2893
d8f43ee6
HK		 2894 when N_If_Expression =>
2895 Resolve_If_Expression (N, Ctx_Type);
996ae0b0 2896
d8f43ee6
HK		 2897 when N_Indexed_Component =>
2898 Resolve_Indexed_Component (N, Ctx_Type);
996ae0b0 2899
d8f43ee6
HK		 2900 when N_Integer_Literal =>
2901 Resolve_Integer_Literal (N, Ctx_Type);
0669bebe 2902
d8f43ee6
HK		 2903 when N_Membership_Test =>
2904 Resolve_Membership_Op (N, Ctx_Type);
996ae0b0 2905
d8f43ee6
HK		 2906 when N_Null =>
2907 Resolve_Null (N, Ctx_Type);
996ae0b0 2908
d8f43ee6
HK		 2909 when N_Op_And
2910 | N_Op_Or
2911 | N_Op_Xor
2912 =>
2913 Resolve_Logical_Op (N, Ctx_Type);
996ae0b0 2914
d8f43ee6
HK		 2915 when N_Op_Eq
2916 | N_Op_Ne
2917 =>
2918 Resolve_Equality_Op (N, Ctx_Type);
996ae0b0 2919
d8f43ee6
HK		 2920 when N_Op_Ge
2921 | N_Op_Gt
2922 | N_Op_Le
2923 | N_Op_Lt
2924 =>
2925 Resolve_Comparison_Op (N, Ctx_Type);
996ae0b0 2926
d8f43ee6
HK		 2927 when N_Op_Not =>
2928 Resolve_Op_Not (N, Ctx_Type);
996ae0b0 2929
d8f43ee6
HK		 2930 when N_Op_Add
2931 | N_Op_Divide
2932 | N_Op_Mod
2933 | N_Op_Multiply
2934 | N_Op_Rem
2935 | N_Op_Subtract
2936 =>
2937 Resolve_Arithmetic_Op (N, Ctx_Type);
996ae0b0 2938
d8f43ee6
HK		 2939 when N_Op_Concat =>
2940 Resolve_Op_Concat (N, Ctx_Type);
996ae0b0 2941
d8f43ee6
HK		 2942 when N_Op_Expon =>
2943 Resolve_Op_Expon (N, Ctx_Type);
996ae0b0 2944
d8f43ee6
HK		 2945 when N_Op_Abs
2946 | N_Op_Minus
2947 | N_Op_Plus
2948 =>
2949 Resolve_Unary_Op (N, Ctx_Type);
996ae0b0 2950
d8f43ee6
HK		 2951 when N_Op_Shift =>
2952 Resolve_Shift (N, Ctx_Type);
996ae0b0 2953
d8f43ee6
HK		 2954 when N_Procedure_Call_Statement =>
2955 Resolve_Call (N, Ctx_Type);
996ae0b0 2956
d8f43ee6
HK		 2957 when N_Operator_Symbol =>
2958 Resolve_Operator_Symbol (N, Ctx_Type);
996ae0b0 2959
d8f43ee6
HK		 2960 when N_Qualified_Expression =>
2961 Resolve_Qualified_Expression (N, Ctx_Type);
996ae0b0 2962
c8d63650
RD		 2963 -- Why is the following null, needs a comment ???
2964
d8f43ee6
HK		 2965 when N_Quantified_Expression =>
2966 null;
983a3d80 2967
d8f43ee6
HK		 2968 when N_Raise_Expression =>
2969 Resolve_Raise_Expression (N, Ctx_Type);
c8d63650 2970
d8f43ee6
HK		 2971 when N_Raise_xxx_Error =>
2972 Set_Etype (N, Ctx_Type);
996ae0b0 2973
d8f43ee6
HK		 2974 when N_Range =>
2975 Resolve_Range (N, Ctx_Type);
996ae0b0 2976
d8f43ee6
HK		 2977 when N_Real_Literal =>
2978 Resolve_Real_Literal (N, Ctx_Type);
996ae0b0 2979
d8f43ee6
HK		 2980 when N_Reference =>
2981 Resolve_Reference (N, Ctx_Type);
996ae0b0 2982
d8f43ee6
HK		 2983 when N_Selected_Component =>
2984 Resolve_Selected_Component (N, Ctx_Type);
996ae0b0 2985
d8f43ee6
HK		 2986 when N_Slice =>
2987 Resolve_Slice (N, Ctx_Type);
996ae0b0 2988
d8f43ee6
HK		 2989 when N_String_Literal =>
2990 Resolve_String_Literal (N, Ctx_Type);
996ae0b0 2991
ae33543c
ES		 2992 when N_Target_Name =>
2993 Resolve_Target_Name (N, Ctx_Type);
2994
d8f43ee6
HK		 2995 when N_Type_Conversion =>
2996 Resolve_Type_Conversion (N, Ctx_Type);
996ae0b0
RK		 2997
2998 when N_Unchecked_Expression =>
d8f43ee6 2999 Resolve_Unchecked_Expression (N, Ctx_Type);
996ae0b0
RK		 3000
3001 when N_Unchecked_Type_Conversion =>
d8f43ee6 3002 Resolve_Unchecked_Type_Conversion (N, Ctx_Type);
996ae0b0
RK		 3003 end case;
3004
6cce2156
GD		 3005 -- Ada 2012 (AI05-0149): Apply an (implicit) conversion to an
3006 -- expression of an anonymous access type that occurs in the context
3007 -- of a named general access type, except when the expression is that
3008 -- of a membership test. This ensures proper legality checking in
3009 -- terms of allowed conversions (expressions that would be illegal to
3010 -- convert implicitly are allowed in membership tests).
3011
3012 if Ada_Version >= Ada_2012
3013 and then Ekind (Ctx_Type) = E_General_Access_Type
3014 and then Ekind (Etype (N)) = E_Anonymous_Access_Type
3015 and then Nkind (Parent (N)) not in N_Membership_Test
3016 then
3017 Rewrite (N, Convert_To (Ctx_Type, Relocate_Node (N)));
3018 Analyze_And_Resolve (N, Ctx_Type);
3019 end if;
3020
996ae0b0
RK		 3021 -- If the subexpression was replaced by a non-subexpression, then
3022 -- all we do is to expand it. The only legitimate case we know of
3023 -- is converting procedure call statement to entry call statements,
3024 -- but there may be others, so we are making this test general.
3025
3026 if Nkind (N) not in N_Subexpr then
3027 Debug_A_Exit ("resolving ", N, " (done)");
3028 Expand (N);
3029 return;
3030 end if;
3031
3032 -- The expression is definitely NOT overloaded at this point, so
3033 -- we reset the Is_Overloaded flag to avoid any confusion when
3034 -- reanalyzing the node.
3035
3036 Set_Is_Overloaded (N, False);
3037
3038 -- Freeze expression type, entity if it is a name, and designated
fbf5a39b 3039 -- type if it is an allocator (RM 13.14(10,11,13)).
996ae0b0 3040
5cc9353d
RD		 3041 -- Now that the resolution of the type of the node is complete, and
3042 -- we did not detect an error, we can expand this node. We skip the
3043 -- expand call if we are in a default expression, see section
3044 -- "Handling of Default Expressions" in Sem spec.
996ae0b0
RK		 3045
3046 Debug_A_Exit ("resolving ", N, " (done)");
3047
3048 -- We unconditionally freeze the expression, even if we are in
5cc9353d
RD		 3049 -- default expression mode (the Freeze_Expression routine tests this
3050 -- flag and only freezes static types if it is set).
996ae0b0 3051
3e65bfab
AC		 3052 -- Ada 2012 (AI05-177): The declaration of an expression function
3053 -- does not cause freezing, but we never reach here in that case.
3054 -- Here we are resolving the corresponding expanded body, so we do
3055 -- need to perform normal freezing.
08f8a983 3056
3e65bfab 3057 Freeze_Expression (N);
996ae0b0
RK		 3058
3059 -- Now we can do the expansion
3060
3061 Expand (N);
3062 end if;
996ae0b0
RK		 3063 end Resolve;
3064
fbf5a39b
AC		 3065 -------------
3066 -- Resolve --
3067 -------------
3068
996ae0b0
RK		 3069 -- Version with check(s) suppressed
3070
3071 procedure Resolve (N : Node_Id; Typ : Entity_Id; Suppress : Check_Id) is
3072 begin
3073 if Suppress = All_Checks then
3074 declare
a7f1b24f 3075 Sva : constant Suppress_Array := Scope_Suppress.Suppress;
996ae0b0 3076 begin
a7f1b24f 3077 Scope_Suppress.Suppress := (others => True);
996ae0b0 3078 Resolve (N, Typ);
a7f1b24f 3079 Scope_Suppress.Suppress := Sva;
996ae0b0
RK		 3080 end;
3081
3082 else
3083 declare
3217f71e 3084 Svg : constant Boolean := Scope_Suppress.Suppress (Suppress);
996ae0b0 3085 begin
3217f71e 3086 Scope_Suppress.Suppress (Suppress) := True;
996ae0b0 3087 Resolve (N, Typ);
3217f71e 3088 Scope_Suppress.Suppress (Suppress) := Svg;
996ae0b0
RK		 3089 end;
3090 end if;
3091 end Resolve;
3092
fbf5a39b
AC		 3093 -------------
3094 -- Resolve --
3095 -------------
3096
3097 -- Version with implicit type
3098
3099 procedure Resolve (N : Node_Id) is
3100 begin
3101 Resolve (N, Etype (N));
3102 end Resolve;
3103
996ae0b0
RK		 3104 ---------------------
3105 -- Resolve_Actuals --
3106 ---------------------
3107
3108 procedure Resolve_Actuals (N : Node_Id; Nam : Entity_Id) is
3109 Loc : constant Source_Ptr := Sloc (N);
3110 A : Node_Id;
97779c34 3111 A_Id : Entity_Id;
996ae0b0 3112 A_Typ : Entity_Id;
97779c34 3113 F : Entity_Id;
996ae0b0
RK		 3114 F_Typ : Entity_Id;
3115 Prev : Node_Id := Empty;
67ce0d7e 3116 Orig_A : Node_Id;
e6b3f5ba
ES		 3117 Real_F : Entity_Id;
3118
3119 Real_Subp : Entity_Id;
4d6a38a5
ES		 3120 -- If the subprogram being called is an inherited operation for
3121 -- a formal derived type in an instance, Real_Subp is the subprogram
3122 -- that will be called. It may have different formal names than the
3123 -- operation of the formal in the generic, so after actual is resolved
3124 -- the name of the actual in a named association must carry the name
3125 -- of the actual of the subprogram being called.
996ae0b0 3126
f3691f46
ES		 3127 procedure Check_Aliased_Parameter;
3128 -- Check rules on aliased parameters and related accessibility rules
fc27e20e 3129 -- in (RM 3.10.2 (10.2-10.4)).
f3691f46 3130
45fc7ddb
HK		 3131 procedure Check_Argument_Order;
3132 -- Performs a check for the case where the actuals are all simple
3133 -- identifiers that correspond to the formal names, but in the wrong
3134 -- order, which is considered suspicious and cause for a warning.
3135
b7d1f17f
HK		 3136 procedure Check_Prefixed_Call;
3137 -- If the original node is an overloaded call in prefix notation,
3138 -- insert an 'Access or a dereference as needed over the first actual.
3139 -- Try_Object_Operation has already verified that there is a valid
3140 -- interpretation, but the form of the actual can only be determined
3141 -- once the primitive operation is identified.
3142
888be6b1
AC		 3143 procedure Flag_Effectively_Volatile_Objects (Expr : Node_Id);
3144 -- Emit an error concerning the illegal usage of an effectively volatile
3145 -- object in interfering context (SPARK RM 7.13(12)).
3146
996ae0b0
RK		 3147 procedure Insert_Default;
3148 -- If the actual is missing in a call, insert in the actuals list
3149 -- an instance of the default expression. The insertion is always
3150 -- a named association.
3151
97779c34
AC		 3152 procedure Property_Error
3153 (Var : Node_Id;
3154 Var_Id : Entity_Id;
3155 Prop_Nam : Name_Id);
3156 -- Emit an error concerning variable Var with entity Var_Id that has
3157 -- enabled property Prop_Nam when it acts as an actual parameter in a
3158 -- call and the corresponding formal parameter is of mode IN.
3159
fbf5a39b
AC		 3160 function Same_Ancestor (T1, T2 : Entity_Id) return Boolean;
3161 -- Check whether T1 and T2, or their full views, are derived from a
3162 -- common type. Used to enforce the restrictions on array conversions
3163 -- of AI95-00246.
3164
a7a3cf5c
AC		 3165 function Static_Concatenation (N : Node_Id) return Boolean;
3166 -- Predicate to determine whether an actual that is a concatenation
3167 -- will be evaluated statically and does not need a transient scope.
3168 -- This must be determined before the actual is resolved and expanded
3169 -- because if needed the transient scope must be introduced earlier.
3170
07a64c02
AC		 3171 -----------------------------
3172 -- Check_Aliased_Parameter --
3173 -----------------------------
f3691f46
ES		 3174
3175 procedure Check_Aliased_Parameter is
3176 Nominal_Subt : Entity_Id;
3177
3178 begin
3179 if Is_Aliased (F) then
3180 if Is_Tagged_Type (A_Typ) then
3181 null;
3182
3183 elsif Is_Aliased_View (A) then
3184 if Is_Constr_Subt_For_U_Nominal (A_Typ) then
3185 Nominal_Subt := Base_Type (A_Typ);
3186 else
3187 Nominal_Subt := A_Typ;
3188 end if;
3189
3190 if Subtypes_Statically_Match (F_Typ, Nominal_Subt) then
3191 null;
3192
3193 -- In a generic body assume the worst for generic formals:
3194 -- they can have a constrained partial view (AI05-041).
3195
3196 elsif Has_Discriminants (F_Typ)
3197 and then not Is_Constrained (F_Typ)
3198 and then not Has_Constrained_Partial_View (F_Typ)
3199 and then not Is_Generic_Type (F_Typ)
3200 then
3201 null;
3202
3203 else
3204 Error_Msg_NE ("untagged actual does not match "
fc27e20e 3205 & "aliased formal&", A, F);
f3691f46
ES		 3206 end if;
3207
3208 else
3209 Error_Msg_NE ("actual for aliased formal& must be "
fc27e20e 3210 & "aliased object", A, F);
f3691f46
ES		 3211 end if;
3212
3213 if Ekind (Nam) = E_Procedure then
3214 null;
3215
3216 elsif Ekind (Etype (Nam)) = E_Anonymous_Access_Type then
3217 if Nkind (Parent (N)) = N_Type_Conversion
fc27e20e
RD		 3218 and then Type_Access_Level (Etype (Parent (N))) <
3219 Object_Access_Level (A)
f3691f46
ES		 3220 then
3221 Error_Msg_N ("aliased actual has wrong accessibility", A);
3222 end if;
3223
3224 elsif Nkind (Parent (N)) = N_Qualified_Expression
3225 and then Nkind (Parent (Parent (N))) = N_Allocator
fc27e20e
RD		 3226 and then Type_Access_Level (Etype (Parent (Parent (N)))) <
3227 Object_Access_Level (A)
f3691f46
ES		 3228 then
3229 Error_Msg_N
fc27e20e 3230 ("aliased actual in allocator has wrong accessibility", A);
f3691f46
ES		 3231 end if;
3232 end if;
3233 end Check_Aliased_Parameter;
3234
45fc7ddb
HK		 3235 --------------------------
3236 -- Check_Argument_Order --
3237 --------------------------
3238
3239 procedure Check_Argument_Order is
3240 begin
3241 -- Nothing to do if no parameters, or original node is neither a
3242 -- function call nor a procedure call statement (happens in the
3243 -- operator-transformed-to-function call case), or the call does
3244 -- not come from source, or this warning is off.
3245
3246 if not Warn_On_Parameter_Order
19fb051c 3247 or else No (Parameter_Associations (N))
d3b00ce3 3248 or else Nkind (Original_Node (N)) not in N_Subprogram_Call
19fb051c 3249 or else not Comes_From_Source (N)
45fc7ddb
HK		 3250 then
3251 return;
3252 end if;
3253
3254 declare
3255 Nargs : constant Nat := List_Length (Parameter_Associations (N));
3256
3257 begin
3258 -- Nothing to do if only one parameter
3259
3260 if Nargs < 2 then
3261 return;
3262 end if;
3263
3264 -- Here if at least two arguments
3265
3266 declare
3267 Actuals : array (1 .. Nargs) of Node_Id;
3268 Actual : Node_Id;
3269 Formal : Node_Id;
3270
3271 Wrong_Order : Boolean := False;
3272 -- Set True if an out of order case is found
3273
3274 begin
3275 -- Collect identifier names of actuals, fail if any actual is
3276 -- not a simple identifier, and record max length of name.
3277
3278 Actual := First (Parameter_Associations (N));
3279 for J in Actuals'Range loop
3280 if Nkind (Actual) /= N_Identifier then
3281 return;
3282 else
3283 Actuals (J) := Actual;
3284 Next (Actual);
3285 end if;
3286 end loop;
3287
3288 -- If we got this far, all actuals are identifiers and the list
3289 -- of their names is stored in the Actuals array.
3290
3291 Formal := First_Formal (Nam);
3292 for J in Actuals'Range loop
3293
3294 -- If we ran out of formals, that's odd, probably an error
3295 -- which will be detected elsewhere, but abandon the search.
3296
3297 if No (Formal) then
3298 return;
3299 end if;
3300
3301 -- If name matches and is in order OK
3302
3303 if Chars (Formal) = Chars (Actuals (J)) then
3304 null;
3305
3306 else
3307 -- If no match, see if it is elsewhere in list and if so
3308 -- flag potential wrong order if type is compatible.
3309
3310 for K in Actuals'Range loop
3311 if Chars (Formal) = Chars (Actuals (K))
3312 and then
3313 Has_Compatible_Type (Actuals (K), Etype (Formal))
3314 then
3315 Wrong_Order := True;
3316 goto Continue;
3317 end if;
3318 end loop;
3319
3320 -- No match
3321
3322 return;
3323 end if;
3324
3325 <<Continue>> Next_Formal (Formal);
3326 end loop;
3327
3328 -- If Formals left over, also probably an error, skip warning
3329
3330 if Present (Formal) then
3331 return;
3332 end if;
3333
3334 -- Here we give the warning if something was out of order
3335
3336 if Wrong_Order then
3337 Error_Msg_N
a3633438 3338 ("?P?actuals for this call may be in wrong order", N);
45fc7ddb
HK		 3339 end if;
3340 end;
3341 end;
3342 end Check_Argument_Order;
3343
b7d1f17f
HK		 3344 -------------------------
3345 -- Check_Prefixed_Call --
3346 -------------------------
3347
3348 procedure Check_Prefixed_Call is
3349 Act : constant Node_Id := First_Actual (N);
3350 A_Type : constant Entity_Id := Etype (Act);
3351 F_Type : constant Entity_Id := Etype (First_Formal (Nam));
3352 Orig : constant Node_Id := Original_Node (N);
3353 New_A : Node_Id;
3354
3355 begin
3356 -- Check whether the call is a prefixed call, with or without
3357 -- additional actuals.
3358
3359 if Nkind (Orig) = N_Selected_Component
3360 or else
3361 (Nkind (Orig) = N_Indexed_Component
3362 and then Nkind (Prefix (Orig)) = N_Selected_Component
3363 and then Is_Entity_Name (Prefix (Prefix (Orig)))
3364 and then Is_Entity_Name (Act)
3365 and then Chars (Act) = Chars (Prefix (Prefix (Orig))))
3366 then
3367 if Is_Access_Type (A_Type)
3368 and then not Is_Access_Type (F_Type)
3369 then
3370 -- Introduce dereference on object in prefix
3371
3372 New_A :=
3373 Make_Explicit_Dereference (Sloc (Act),
3374 Prefix => Relocate_Node (Act));
3375 Rewrite (Act, New_A);
3376 Analyze (Act);
3377
3378 elsif Is_Access_Type (F_Type)
3379 and then not Is_Access_Type (A_Type)
3380 then
3381 -- Introduce an implicit 'Access in prefix
3382
3383 if not Is_Aliased_View (Act) then
ed2233dc 3384 Error_Msg_NE
039538bc 3385 ("object in prefixed call to& must be aliased "
715e529d 3386 & "(RM 4.1.3 (13 1/2))",
b7d1f17f
HK		 3387 Prefix (Act), Nam);
3388 end if;
3389
3390 Rewrite (Act,
3391 Make_Attribute_Reference (Loc,
3392 Attribute_Name => Name_Access,
3393 Prefix => Relocate_Node (Act)));
3394 end if;
3395
3396 Analyze (Act);
3397 end if;
3398 end Check_Prefixed_Call;
3399
888be6b1
AC		 3400 ---------------------------------------
3401 -- Flag_Effectively_Volatile_Objects --
3402 ---------------------------------------
3403
3404 procedure Flag_Effectively_Volatile_Objects (Expr : Node_Id) is
3405 function Flag_Object (N : Node_Id) return Traverse_Result;
3406 -- Determine whether arbitrary node N denotes an effectively volatile
3407 -- object and if it does, emit an error.
3408
3409 -----------------
3410 -- Flag_Object --
3411 -----------------
3412
3413 function Flag_Object (N : Node_Id) return Traverse_Result is
3414 Id : Entity_Id;
3415
3416 begin
3417 -- Do not consider nested function calls because they have already
3418 -- been processed during their own resolution.
3419
3420 if Nkind (N) = N_Function_Call then
3421 return Skip;
3422
3423 elsif Is_Entity_Name (N) and then Present (Entity (N)) then
3424 Id := Entity (N);
3425
3426 if Is_Object (Id)
3427 and then Is_Effectively_Volatile (Id)
3428 and then (Async_Writers_Enabled (Id)
3429 or else Effective_Reads_Enabled (Id))
3430 then
3431 Error_Msg_N
3432 ("volatile object cannot appear in this context (SPARK "
3433 & "RM 7.1.3(11))", N);
3434 return Skip;
3435 end if;
3436 end if;
3437
3438 return OK;
3439 end Flag_Object;
3440
3441 procedure Flag_Objects is new Traverse_Proc (Flag_Object);
3442
3443 -- Start of processing for Flag_Effectively_Volatile_Objects
3444
3445 begin
3446 Flag_Objects (Expr);
3447 end Flag_Effectively_Volatile_Objects;
3448
996ae0b0
RK		 3449 --------------------
3450 -- Insert_Default --
3451 --------------------
3452
3453 procedure Insert_Default is
3454 Actval : Node_Id;
3455 Assoc : Node_Id;
3456
3457 begin
fbf5a39b 3458 -- Missing argument in call, nothing to insert
996ae0b0 3459
fbf5a39b
AC		 3460 if No (Default_Value (F)) then
3461 return;
3462
3463 else
3464 -- Note that we do a full New_Copy_Tree, so that any associated
3465 -- Itypes are properly copied. This may not be needed any more,
a90bd866 3466 -- but it does no harm as a safety measure. Defaults of a generic
fbf5a39b
AC		 3467 -- formal may be out of bounds of the corresponding actual (see
3468 -- cc1311b) and an additional check may be required.
996ae0b0 3469
b7d1f17f
HK		 3470 Actval :=
3471 New_Copy_Tree
3472 (Default_Value (F),
3473 New_Scope => Current_Scope,
3474 New_Sloc => Loc);
996ae0b0 3475
e90e9503
AC		 3476 -- Propagate dimension information, if any.
3477
3478 Copy_Dimensions (Default_Value (F), Actval);
3479
996ae0b0
RK		 3480 if Is_Concurrent_Type (Scope (Nam))
3481 and then Has_Discriminants (Scope (Nam))
3482 then
3483 Replace_Actual_Discriminants (N, Actval);
3484 end if;
3485
3486 if Is_Overloadable (Nam)
3487 and then Present (Alias (Nam))
3488 then
3489 if Base_Type (Etype (F)) /= Base_Type (Etype (Actval))
3490 and then not Is_Tagged_Type (Etype (F))
3491 then
3492 -- If default is a real literal, do not introduce a
3493 -- conversion whose effect may depend on the run-time
3494 -- size of universal real.
3495
3496 if Nkind (Actval) = N_Real_Literal then
3497 Set_Etype (Actval, Base_Type (Etype (F)));
3498 else
3499 Actval := Unchecked_Convert_To (Etype (F), Actval);
3500 end if;
3501 end if;
3502
3503 if Is_Scalar_Type (Etype (F)) then
3504 Enable_Range_Check (Actval);
3505 end if;
3506
996ae0b0
RK		 3507 Set_Parent (Actval, N);
3508
3509 -- Resolve aggregates with their base type, to avoid scope
f3d57416 3510 -- anomalies: the subtype was first built in the subprogram
996ae0b0
RK		 3511 -- declaration, and the current call may be nested.
3512
76b84bf0
AC		 3513 if Nkind (Actval) = N_Aggregate then
3514 Analyze_And_Resolve (Actval, Etype (F));
996ae0b0
RK		 3515 else
3516 Analyze_And_Resolve (Actval, Etype (Actval));
3517 end if;
fbf5a39b
AC		 3518
3519 else
3520 Set_Parent (Actval, N);
3521
a77842bd 3522 -- See note above concerning aggregates
fbf5a39b
AC		 3523
3524 if Nkind (Actval) = N_Aggregate
3525 and then Has_Discriminants (Etype (Actval))
3526 then
3527 Analyze_And_Resolve (Actval, Base_Type (Etype (Actval)));
3528
5cc9353d
RD		 3529 -- Resolve entities with their own type, which may differ from
3530 -- the type of a reference in a generic context (the view
3531 -- swapping mechanism did not anticipate the re-analysis of
3532 -- default values in calls).
fbf5a39b
AC		 3533
3534 elsif Is_Entity_Name (Actval) then
3535 Analyze_And_Resolve (Actval, Etype (Entity (Actval)));
3536
3537 else
3538 Analyze_And_Resolve (Actval, Etype (Actval));
3539 end if;
996ae0b0
RK		 3540 end if;
3541
5cc9353d
RD		 3542 -- If default is a tag indeterminate function call, propagate tag
3543 -- to obtain proper dispatching.
996ae0b0
RK		 3544
3545 if Is_Controlling_Formal (F)
3546 and then Nkind (Default_Value (F)) = N_Function_Call
3547 then
3548 Set_Is_Controlling_Actual (Actval);
3549 end if;
996ae0b0
RK		 3550 end if;
3551
3552 -- If the default expression raises constraint error, then just
5cc9353d
RD		 3553 -- silently replace it with an N_Raise_Constraint_Error node, since
3554 -- we already gave the warning on the subprogram spec. If node is
3555 -- already a Raise_Constraint_Error leave as is, to prevent loops in
3556 -- the warnings removal machinery.
996ae0b0 3557
2604ec03
AC		 3558 if Raises_Constraint_Error (Actval)
3559 and then Nkind (Actval) /= N_Raise_Constraint_Error
3560 then
996ae0b0 3561 Rewrite (Actval,
07fc65c4
GB		 3562 Make_Raise_Constraint_Error (Loc,
3563 Reason => CE_Range_Check_Failed));
996ae0b0
RK		 3564 Set_Raises_Constraint_Error (Actval);
3565 Set_Etype (Actval, Etype (F));
3566 end if;
3567
3568 Assoc :=
3569 Make_Parameter_Association (Loc,
3570 Explicit_Actual_Parameter => Actval,
3571 Selector_Name => Make_Identifier (Loc, Chars (F)));
3572
3573 -- Case of insertion is first named actual
3574
3575 if No (Prev) or else
3576 Nkind (Parent (Prev)) /= N_Parameter_Association
3577 then
3578 Set_Next_Named_Actual (Assoc, First_Named_Actual (N));
3579 Set_First_Named_Actual (N, Actval);
3580
3581 if No (Prev) then
c8ef728f 3582 if No (Parameter_Associations (N)) then
996ae0b0
RK		 3583 Set_Parameter_Associations (N, New_List (Assoc));
3584 else
3585 Append (Assoc, Parameter_Associations (N));
3586 end if;
3587
3588 else
3589 Insert_After (Prev, Assoc);
3590 end if;
3591
3592 -- Case of insertion is not first named actual
3593
3594 else
3595 Set_Next_Named_Actual
3596 (Assoc, Next_Named_Actual (Parent (Prev)));
3597 Set_Next_Named_Actual (Parent (Prev), Actval);
3598 Append (Assoc, Parameter_Associations (N));
3599 end if;
3600
3601 Mark_Rewrite_Insertion (Assoc);
3602 Mark_Rewrite_Insertion (Actval);
3603
3604 Prev := Actval;
3605 end Insert_Default;
3606
97779c34
AC		 3607 --------------------
3608 -- Property_Error --
3609 --------------------
3610
3611 procedure Property_Error
3612 (Var : Node_Id;
3613 Var_Id : Entity_Id;
3614 Prop_Nam : Name_Id)
3615 is
3616 begin
3617 Error_Msg_Name_1 := Prop_Nam;
3618 Error_Msg_NE
3619 ("external variable & with enabled property % cannot appear as "
db7e3721 3620 & "actual in procedure call (SPARK RM 7.1.3(10))", Var, Var_Id);
97779c34
AC		 3621 Error_Msg_N ("\\corresponding formal parameter has mode In", Var);
3622 end Property_Error;
3623
fbf5a39b
AC		 3624 -------------------
3625 -- Same_Ancestor --
3626 -------------------
3627
3628 function Same_Ancestor (T1, T2 : Entity_Id) return Boolean is
3629 FT1 : Entity_Id := T1;
3630 FT2 : Entity_Id := T2;
3631
3632 begin
3633 if Is_Private_Type (T1)
3634 and then Present (Full_View (T1))
3635 then
3636 FT1 := Full_View (T1);
3637 end if;
3638
3639 if Is_Private_Type (T2)
3640 and then Present (Full_View (T2))
3641 then
3642 FT2 := Full_View (T2);
3643 end if;
3644
3645 return Root_Type (Base_Type (FT1)) = Root_Type (Base_Type (FT2));
3646 end Same_Ancestor;
3647
a7a3cf5c
AC		 3648 --------------------------
3649 -- Static_Concatenation --
3650 --------------------------
3651
3652 function Static_Concatenation (N : Node_Id) return Boolean is
3653 begin
c72a85f2
TQ		 3654 case Nkind (N) is
3655 when N_String_Literal =>
3656 return True;
a7a3cf5c 3657
d81b4bfe
TQ		 3658 when N_Op_Concat =>
3659
5cc9353d
RD		 3660 -- Concatenation is static when both operands are static and
3661 -- the concatenation operator is a predefined one.
4342eda9
TQ		 3662
3663 return Scope (Entity (N)) = Standard_Standard
3664 and then
3665 Static_Concatenation (Left_Opnd (N))
c72a85f2
TQ		 3666 and then
3667 Static_Concatenation (Right_Opnd (N));
3668
3669 when others =>
3670 if Is_Entity_Name (N) then
3671 declare
3672 Ent : constant Entity_Id := Entity (N);
3673 begin
3674 return Ekind (Ent) = E_Constant
3675 and then Present (Constant_Value (Ent))
d81b4bfe 3676 and then
edab6088 3677 Is_OK_Static_Expression (Constant_Value (Ent));
c72a85f2 3678 end;
a7a3cf5c 3679
a7a3cf5c
AC		 3680 else
3681 return False;
3682 end if;
c72a85f2 3683 end case;
a7a3cf5c
AC		 3684 end Static_Concatenation;
3685
996ae0b0
RK		 3686 -- Start of processing for Resolve_Actuals
3687
3688 begin
45fc7ddb
HK		 3689 Check_Argument_Order;
3690
e6b3f5ba
ES		 3691 if Is_Overloadable (Nam)
3692 and then Is_Inherited_Operation (Nam)
4d6a38a5 3693 and then In_Instance
e6b3f5ba
ES		 3694 and then Present (Alias (Nam))
3695 and then Present (Overridden_Operation (Alias (Nam)))
3696 then
3697 Real_Subp := Alias (Nam);
3698 else
3699 Real_Subp := Empty;
3700 end if;
3701
b7d1f17f
HK		 3702 if Present (First_Actual (N)) then
3703 Check_Prefixed_Call;
3704 end if;
3705
996ae0b0
RK		 3706 A := First_Actual (N);
3707 F := First_Formal (Nam);
e6b3f5ba
ES		 3708
3709 if Present (Real_Subp) then
3710 Real_F := First_Formal (Real_Subp);
3711 end if;
3712
996ae0b0 3713 while Present (F) loop
fbf5a39b
AC		 3714 if No (A) and then Needs_No_Actuals (Nam) then
3715 null;
996ae0b0 3716
d81b4bfe
TQ		 3717 -- If we have an error in any actual or formal, indicated by a type
3718 -- of Any_Type, then abandon resolution attempt, and set result type
7610fee8
AC		 3719 -- to Any_Type. Skip this if the actual is a Raise_Expression, whose
3720 -- type is imposed from context.
07fc65c4 3721
fbf5a39b
AC		 3722 elsif (Present (A) and then Etype (A) = Any_Type)
3723 or else Etype (F) = Any_Type
07fc65c4 3724 then
7610fee8
AC		 3725 if Nkind (A) /= N_Raise_Expression then
3726 Set_Etype (N, Any_Type);
3727 return;
3728 end if;
07fc65c4
GB		 3729 end if;
3730
e65f50ec
ES		 3731 -- Case where actual is present
3732
45fc7ddb 3733 -- If the actual is an entity, generate a reference to it now. We
36fcf362
RD		 3734 -- do this before the actual is resolved, because a formal of some
3735 -- protected subprogram, or a task discriminant, will be rewritten
5cc9353d 3736 -- during expansion, and the source entity reference may be lost.
36fcf362
RD		 3737
3738 if Present (A)
3739 and then Is_Entity_Name (A)
0da343bc 3740 and then Comes_From_Source (A)
36fcf362
RD		 3741 then
3742 Orig_A := Entity (A);
3743
3744 if Present (Orig_A) then
3745 if Is_Formal (Orig_A)
3746 and then Ekind (F) /= E_In_Parameter
3747 then
3748 Generate_Reference (Orig_A, A, 'm');
19fb051c 3749
36fcf362 3750 elsif not Is_Overloaded (A) then
ba08ba84
AC		 3751 if Ekind (F) /= E_Out_Parameter then
3752 Generate_Reference (Orig_A, A);
3753
3754 -- RM 6.4.1(12): For an out parameter that is passed by
3755 -- copy, the formal parameter object is created, and:
3756
3757 -- * For an access type, the formal parameter is initialized
3758 -- from the value of the actual, without checking that the
3759 -- value satisfies any constraint, any predicate, or any
3760 -- exclusion of the null value.
3761
3762 -- * For a scalar type that has the Default_Value aspect
3763 -- specified, the formal parameter is initialized from the
3764 -- value of the actual, without checking that the value
c91dbd18
AC		 3765 -- satisfies any constraint or any predicate.
3766 -- I do not understand why this case is included??? this is
3767 -- not a case where an OUT parameter is treated as IN OUT.
ba08ba84
AC		 3768
3769 -- * For a composite type with discriminants or that has
3770 -- implicit initial values for any subcomponents, the
3771 -- behavior is as for an in out parameter passed by copy.
3772
3773 -- Hence for these cases we generate the read reference now
3774 -- (the write reference will be generated later by
3775 -- Note_Possible_Modification).
3776
3777 elsif Is_By_Copy_Type (Etype (F))
3778 and then
3779 (Is_Access_Type (Etype (F))
3780 or else
3781 (Is_Scalar_Type (Etype (F))
3782 and then
3783 Present (Default_Aspect_Value (Etype (F))))
3784 or else
3785 (Is_Composite_Type (Etype (F))
c91dbd18
AC		 3786 and then (Has_Discriminants (Etype (F))
3787 or else Is_Partially_Initialized_Type
3788 (Etype (F)))))
ba08ba84
AC		 3789 then
3790 Generate_Reference (Orig_A, A);
3791 end if;
36fcf362
RD		 3792 end if;
3793 end if;
3794 end if;
3795
996ae0b0
RK		 3796 if Present (A)
3797 and then (Nkind (Parent (A)) /= N_Parameter_Association
19fb051c 3798 or else Chars (Selector_Name (Parent (A))) = Chars (F))
996ae0b0 3799 then
45fc7ddb
HK		 3800 -- If style checking mode on, check match of formal name
3801
3802 if Style_Check then
3803 if Nkind (Parent (A)) = N_Parameter_Association then
3804 Check_Identifier (Selector_Name (Parent (A)), F);
3805 end if;
3806 end if;
3807
996ae0b0
RK		 3808 -- If the formal is Out or In_Out, do not resolve and expand the
3809 -- conversion, because it is subsequently expanded into explicit
3810 -- temporaries and assignments. However, the object of the
ea985d95
RD		 3811 -- conversion can be resolved. An exception is the case of tagged
3812 -- type conversion with a class-wide actual. In that case we want
3813 -- the tag check to occur and no temporary will be needed (no
3814 -- representation change can occur) and the parameter is passed by
3815 -- reference, so we go ahead and resolve the type conversion.
c8ef728f 3816 -- Another exception is the case of reference to component or
ea985d95
RD		 3817 -- subcomponent of a bit-packed array, in which case we want to
3818 -- defer expansion to the point the in and out assignments are
3819 -- performed.
996ae0b0
RK		 3820
3821 if Ekind (F) /= E_In_Parameter
3822 and then Nkind (A) = N_Type_Conversion
3823 and then not Is_Class_Wide_Type (Etype (Expression (A)))
3824 then
07fc65c4
GB		 3825 if Ekind (F) = E_In_Out_Parameter
3826 and then Is_Array_Type (Etype (F))
07fc65c4 3827 then
038140ed
AC		 3828 -- In a view conversion, the conversion must be legal in
3829 -- both directions, and thus both component types must be
3830 -- aliased, or neither (4.6 (8)).
758c442c 3831
038140ed
AC		 3832 -- The extra rule in 4.6 (24.9.2) seems unduly restrictive:
3833 -- the privacy requirement should not apply to generic
3834 -- types, and should be checked in an instance. ARG query
3835 -- is in order ???
45fc7ddb 3836
038140ed
AC		 3837 if Has_Aliased_Components (Etype (Expression (A))) /=
3838 Has_Aliased_Components (Etype (F))
3839 then
45fc7ddb
HK		 3840 Error_Msg_N
3841 ("both component types in a view conversion must be"
3842 & " aliased, or neither", A);
3843
038140ed
AC		 3844 -- Comment here??? what set of cases???
3845
45fc7ddb
HK		 3846 elsif
3847 not Same_Ancestor (Etype (F), Etype (Expression (A)))
3848 then
038140ed
AC		 3849 -- Check view conv between unrelated by ref array types
3850
45fc7ddb
HK		 3851 if Is_By_Reference_Type (Etype (F))
3852 or else Is_By_Reference_Type (Etype (Expression (A)))
758c442c
GD		 3853 then
3854 Error_Msg_N
1486a00e
AC		 3855 ("view conversion between unrelated by reference "
3856 & "array types not allowed (\'A'I-00246)", A);
038140ed
AC		 3857
3858 -- In Ada 2005 mode, check view conversion component
3859 -- type cannot be private, tagged, or volatile. Note
3860 -- that we only apply this to source conversions. The
3861 -- generated code can contain conversions which are
3862 -- not subject to this test, and we cannot extract the
3863 -- component type in such cases since it is not present.
3864
3865 elsif Comes_From_Source (A)
3866 and then Ada_Version >= Ada_2005
3867 then
45fc7ddb
HK		 3868 declare
3869 Comp_Type : constant Entity_Id :=
3870 Component_Type
3871 (Etype (Expression (A)));
3872 begin
038140ed
AC		 3873 if (Is_Private_Type (Comp_Type)
3874 and then not Is_Generic_Type (Comp_Type))
3875 or else Is_Tagged_Type (Comp_Type)
3876 or else Is_Volatile (Comp_Type)
45fc7ddb
HK		 3877 then
3878 Error_Msg_N
3879 ("component type of a view conversion cannot"
3880 & " be private, tagged, or volatile"
3881 & " (RM 4.6 (24))",
3882 Expression (A));
3883 end if;
3884 end;
758c442c 3885 end if;
fbf5a39b 3886 end if;
07fc65c4
GB		 3887 end if;
3888
038140ed
AC		 3889 -- Resolve expression if conversion is all OK
3890
16397eff 3891 if (Conversion_OK (A)
038140ed 3892 or else Valid_Conversion (A, Etype (A), Expression (A)))
16397eff 3893 and then not Is_Ref_To_Bit_Packed_Array (Expression (A))
996ae0b0 3894 then
fbf5a39b 3895 Resolve (Expression (A));
996ae0b0
RK		 3896 end if;
3897
b7d1f17f
HK		 3898 -- If the actual is a function call that returns a limited
3899 -- unconstrained object that needs finalization, create a
3900 -- transient scope for it, so that it can receive the proper
3901 -- finalization list.
3902
3903 elsif Nkind (A) = N_Function_Call
3904 and then Is_Limited_Record (Etype (F))
3905 and then not Is_Constrained (Etype (F))
4460a9bc 3906 and then Expander_Active
19fb051c 3907 and then (Is_Controlled (Etype (F)) or else Has_Task (Etype (F)))
b7d1f17f 3908 then
13b2f7fd 3909 Establish_Transient_Scope (A, Sec_Stack => False);
24a120ac 3910 Resolve (A, Etype (F));
b7d1f17f 3911
a52fefe6
AC		 3912 -- A small optimization: if one of the actuals is a concatenation
3913 -- create a block around a procedure call to recover stack space.
3914 -- This alleviates stack usage when several procedure calls in
76e776e5
AC		 3915 -- the same statement list use concatenation. We do not perform
3916 -- this wrapping for code statements, where the argument is a
3917 -- static string, and we want to preserve warnings involving
3918 -- sequences of such statements.
a52fefe6
AC		 3919
3920 elsif Nkind (A) = N_Op_Concat
3921 and then Nkind (N) = N_Procedure_Call_Statement
4460a9bc 3922 and then Expander_Active
76e776e5
AC		 3923 and then
3924 not (Is_Intrinsic_Subprogram (Nam)
3925 and then Chars (Nam) = Name_Asm)
a7a3cf5c 3926 and then not Static_Concatenation (A)
a52fefe6 3927 then
13b2f7fd 3928 Establish_Transient_Scope (A, Sec_Stack => False);
a52fefe6
AC		 3929 Resolve (A, Etype (F));
3930
996ae0b0 3931 else
fbf5a39b
AC		 3932 if Nkind (A) = N_Type_Conversion
3933 and then Is_Array_Type (Etype (F))
3934 and then not Same_Ancestor (Etype (F), Etype (Expression (A)))
3935 and then
3936 (Is_Limited_Type (Etype (F))
2e86f679 3937 or else Is_Limited_Type (Etype (Expression (A))))
fbf5a39b
AC		 3938 then
3939 Error_Msg_N
1486a00e 3940 ("conversion between unrelated limited array types "
2590ef12 3941 & "not allowed ('A'I-00246)", A);
fbf5a39b 3942
758c442c
GD		 3943 if Is_Limited_Type (Etype (F)) then
3944 Explain_Limited_Type (Etype (F), A);
3945 end if;
fbf5a39b 3946
758c442c
GD		 3947 if Is_Limited_Type (Etype (Expression (A))) then
3948 Explain_Limited_Type (Etype (Expression (A)), A);
3949 end if;
fbf5a39b
AC		 3950 end if;
3951
c8ef728f
ES		 3952 -- (Ada 2005: AI-251): If the actual is an allocator whose
3953 -- directly designated type is a class-wide interface, we build
3954 -- an anonymous access type to use it as the type of the
3955 -- allocator. Later, when the subprogram call is expanded, if
3956 -- the interface has a secondary dispatch table the expander
3957 -- will add a type conversion to force the correct displacement
3958 -- of the pointer.
3959
3960 if Nkind (A) = N_Allocator then
3961 declare
3962 DDT : constant Entity_Id :=
3963 Directly_Designated_Type (Base_Type (Etype (F)));
45fc7ddb 3964
c8ef728f 3965 New_Itype : Entity_Id;
45fc7ddb 3966
c8ef728f
ES		 3967 begin
3968 if Is_Class_Wide_Type (DDT)
3969 and then Is_Interface (DDT)
3970 then
3971 New_Itype := Create_Itype (E_Anonymous_Access_Type, A);
45fc7ddb 3972 Set_Etype (New_Itype, Etype (A));
2590ef12
RD		 3973 Set_Directly_Designated_Type
3974 (New_Itype, Directly_Designated_Type (Etype (A)));
c8ef728f
ES		 3975 Set_Etype (A, New_Itype);
3976 end if;
0669bebe
GB		 3977
3978 -- Ada 2005, AI-162:If the actual is an allocator, the
3979 -- innermost enclosing statement is the master of the
b7d1f17f
HK		 3980 -- created object. This needs to be done with expansion
3981 -- enabled only, otherwise the transient scope will not
3982 -- be removed in the expansion of the wrapped construct.
0669bebe 3983
45fc7ddb 3984 if (Is_Controlled (DDT) or else Has_Task (DDT))
4460a9bc 3985 and then Expander_Active
0669bebe 3986 then
13b2f7fd 3987 Establish_Transient_Scope (A, Sec_Stack => False);
0669bebe 3988 end if;
c8ef728f 3989 end;
57f4c288
ES		 3990
3991 if Ekind (Etype (F)) = E_Anonymous_Access_Type then
3992 Check_Restriction (No_Access_Parameter_Allocators, A);
3993 end if;
c8ef728f
ES		 3994 end if;
3995
2e86f679
RD		 3996 -- (Ada 2005): The call may be to a primitive operation of a
3997 -- tagged synchronized type, declared outside of the type. In
3998 -- this case the controlling actual must be converted to its
3999 -- corresponding record type, which is the formal type. The
4000 -- actual may be a subtype, either because of a constraint or
4001 -- because it is a generic actual, so use base type to locate
4002 -- concurrent type.
b7d1f17f 4003
15e4986c
JM		 4004 F_Typ := Base_Type (Etype (F));
4005
cb7fa356
AC		 4006 if Is_Tagged_Type (F_Typ)
4007 and then (Is_Concurrent_Type (F_Typ)
2590ef12 4008 or else Is_Concurrent_Record_Type (F_Typ))
cb7fa356
AC		 4009 then
4010 -- If the actual is overloaded, look for an interpretation
4011 -- that has a synchronized type.
4012
4013 if not Is_Overloaded (A) then
4014 A_Typ := Base_Type (Etype (A));
15e4986c 4015
15e4986c 4016 else
cb7fa356
AC		 4017 declare
4018 Index : Interp_Index;
4019 It : Interp;
218e6dee 4020
cb7fa356
AC		 4021 begin
4022 Get_First_Interp (A, Index, It);
4023 while Present (It.Typ) loop
4024 if Is_Concurrent_Type (It.Typ)
4025 or else Is_Concurrent_Record_Type (It.Typ)
4026 then
4027 A_Typ := Base_Type (It.Typ);
4028 exit;
4029 end if;
4030
4031 Get_Next_Interp (Index, It);
4032 end loop;
4033 end;
15e4986c 4034 end if;
b7d1f17f 4035
cb7fa356
AC		 4036 declare
4037 Full_A_Typ : Entity_Id;
15e4986c 4038
cb7fa356
AC		 4039 begin
4040 if Present (Full_View (A_Typ)) then
4041 Full_A_Typ := Base_Type (Full_View (A_Typ));
4042 else
4043 Full_A_Typ := A_Typ;
4044 end if;
4045
4046 -- Tagged synchronized type (case 1): the actual is a
4047 -- concurrent type.
4048
4049 if Is_Concurrent_Type (A_Typ)
4050 and then Corresponding_Record_Type (A_Typ) = F_Typ
4051 then
4052 Rewrite (A,
4053 Unchecked_Convert_To
4054 (Corresponding_Record_Type (A_Typ), A));
4055 Resolve (A, Etype (F));
15e4986c 4056
cb7fa356
AC		 4057 -- Tagged synchronized type (case 2): the formal is a
4058 -- concurrent type.
15e4986c 4059
cb7fa356
AC		 4060 elsif Ekind (Full_A_Typ) = E_Record_Type
4061 and then Present
15e4986c 4062 (Corresponding_Concurrent_Type (Full_A_Typ))
cb7fa356
AC		 4063 and then Is_Concurrent_Type (F_Typ)
4064 and then Present (Corresponding_Record_Type (F_Typ))
4065 and then Full_A_Typ = Corresponding_Record_Type (F_Typ)
4066 then
4067 Resolve (A, Corresponding_Record_Type (F_Typ));
15e4986c 4068
cb7fa356 4069 -- Common case
15e4986c 4070
cb7fa356
AC		 4071 else
4072 Resolve (A, Etype (F));
4073 end if;
4074 end;
cb7fa356 4075
2590ef12 4076 -- Not a synchronized operation
cb7fa356 4077
2590ef12 4078 else
cb7fa356
AC		 4079 Resolve (A, Etype (F));
4080 end if;
996ae0b0
RK		 4081 end if;
4082
4083 A_Typ := Etype (A);
4084 F_Typ := Etype (F);
4085
1ebc2612
AC		 4086 -- An actual cannot be an untagged formal incomplete type
4087
4088 if Ekind (A_Typ) = E_Incomplete_Type
4089 and then not Is_Tagged_Type (A_Typ)
4090 and then Is_Generic_Type (A_Typ)
4091 then
4092 Error_Msg_N
4093 ("invalid use of untagged formal incomplete type", A);
4094 end if;
4095
e24329cd 4096 if Comes_From_Source (Original_Node (N))
6320f5e1
AC		 4097 and then Nkind_In (Original_Node (N), N_Function_Call,
4098 N_Procedure_Call_Statement)
b0186f71 4099 then
e24329cd
YM		 4100 -- In formal mode, check that actual parameters matching
4101 -- formals of tagged types are objects (or ancestor type
4102 -- conversions of objects), not general expressions.
780d052e 4103
e24329cd 4104 if Is_Actual_Tagged_Parameter (A) then
ce5ba43a 4105 if Is_SPARK_05_Object_Reference (A) then
e24329cd
YM		 4106 null;
4107
4108 elsif Nkind (A) = N_Type_Conversion then
4109 declare
4110 Operand : constant Node_Id := Expression (A);
4111 Operand_Typ : constant Entity_Id := Etype (Operand);
4112 Target_Typ : constant Entity_Id := A_Typ;
4113
4114 begin
ce5ba43a
AC		 4115 if not Is_SPARK_05_Object_Reference (Operand) then
4116 Check_SPARK_05_Restriction
e24329cd
YM		 4117 ("object required", Operand);
4118
4119 -- In formal mode, the only view conversions are those
4120 -- involving ancestor conversion of an extended type.
4121
4122 elsif not
4123 (Is_Tagged_Type (Target_Typ)
780d052e
RD		 4124 and then not Is_Class_Wide_Type (Target_Typ)
4125 and then Is_Tagged_Type (Operand_Typ)
4126 and then not Is_Class_Wide_Type (Operand_Typ)
4127 and then Is_Ancestor (Target_Typ, Operand_Typ))
e24329cd
YM		 4128 then
4129 if Ekind_In
4130 (F, E_Out_Parameter, E_In_Out_Parameter)
4131 then
ce5ba43a 4132 Check_SPARK_05_Restriction
e24329cd
YM		 4133 ("ancestor conversion is the only permitted "
4134 & "view conversion", A);
4135 else
ce5ba43a 4136 Check_SPARK_05_Restriction
e24329cd
YM		 4137 ("ancestor conversion required", A);
4138 end if;
4139
4140 else
4141 null;
4142 end if;
4143 end;
4144
4145 else
ce5ba43a 4146 Check_SPARK_05_Restriction ("object required", A);
b0186f71 4147 end if;
e24329cd
YM		 4148
4149 -- In formal mode, the only view conversions are those
4150 -- involving ancestor conversion of an extended type.
4151
4152 elsif Nkind (A) = N_Type_Conversion
4153 and then Ekind_In (F, E_Out_Parameter, E_In_Out_Parameter)
4154 then
ce5ba43a 4155 Check_SPARK_05_Restriction
e24329cd
YM		 4156 ("ancestor conversion is the only permitted view "
4157 & "conversion", A);
4158 end if;
b0186f71
AC		 4159 end if;
4160
26570b21
RD		 4161 -- has warnings suppressed, then we reset Never_Set_In_Source for
4162 -- the calling entity. The reason for this is to catch cases like
4163 -- GNAT.Spitbol.Patterns.Vstring_Var where the called subprogram
4164 -- uses trickery to modify an IN parameter.
4165
4166 if Ekind (F) = E_In_Parameter
4167 and then Is_Entity_Name (A)
4168 and then Present (Entity (A))
4169 and then Ekind (Entity (A)) = E_Variable
4170 and then Has_Warnings_Off (F_Typ)
4171 then
4172 Set_Never_Set_In_Source (Entity (A), False);
4173 end if;
4174
fbf5a39b
AC		 4175 -- Perform error checks for IN and IN OUT parameters
4176
4177 if Ekind (F) /= E_Out_Parameter then
4178
4179 -- Check unset reference. For scalar parameters, it is clearly
4180 -- wrong to pass an uninitialized value as either an IN or
4181 -- IN-OUT parameter. For composites, it is also clearly an
4182 -- error to pass a completely uninitialized value as an IN
4183 -- parameter, but the case of IN OUT is trickier. We prefer
4184 -- not to give a warning here. For example, suppose there is
4185 -- a routine that sets some component of a record to False.
4186 -- It is perfectly reasonable to make this IN-OUT and allow
4187 -- either initialized or uninitialized records to be passed
4188 -- in this case.
4189
4190 -- For partially initialized composite values, we also avoid
4191 -- warnings, since it is quite likely that we are passing a
4192 -- partially initialized value and only the initialized fields
4193 -- will in fact be read in the subprogram.
4194
4195 if Is_Scalar_Type (A_Typ)
4196 or else (Ekind (F) = E_In_Parameter
19fb051c 4197 and then not Is_Partially_Initialized_Type (A_Typ))
996ae0b0 4198 then
fbf5a39b 4199 Check_Unset_Reference (A);
996ae0b0 4200 end if;
996ae0b0 4201
758c442c 4202 -- In Ada 83 we cannot pass an OUT parameter as an IN or IN OUT
a921e83c
AC		 4203 -- actual to a nested call, since this constitutes a reading of
4204 -- the parameter, which is not allowed.
996ae0b0 4205
847d950d
HK		 4206 if Ada_Version = Ada_83
4207 and then Is_Entity_Name (A)
996ae0b0
RK		 4208 and then Ekind (Entity (A)) = E_Out_Parameter
4209 then
847d950d 4210 Error_Msg_N ("(Ada 83) illegal reading of out parameter", A);
996ae0b0
RK		 4211 end if;
4212 end if;
4213
a267d8cc
AC		 4214 -- In -gnatd.q mode, forget that a given array is constant when
4215 -- it is passed as an IN parameter to a foreign-convention
4216 -- subprogram. This is in case the subprogram evilly modifies the
4217 -- object. Of course, correct code would use IN OUT.
4218
4219 if Debug_Flag_Dot_Q
4220 and then Ekind (F) = E_In_Parameter
4221 and then Has_Foreign_Convention (Nam)
4222 and then Is_Array_Type (F_Typ)
4223 and then Nkind (A) in N_Has_Entity
4224 and then Present (Entity (A))
4225 then
4226 Set_Is_True_Constant (Entity (A), False);
4227 end if;
4228
67ce0d7e
RD		 4229 -- Case of OUT or IN OUT parameter
4230
36fcf362 4231 if Ekind (F) /= E_In_Parameter then
67ce0d7e
RD		 4232
4233 -- For an Out parameter, check for useless assignment. Note
45fc7ddb
HK		 4234 -- that we can't set Last_Assignment this early, because we may
4235 -- kill current values in Resolve_Call, and that call would
4236 -- clobber the Last_Assignment field.
67ce0d7e 4237
45fc7ddb
HK		 4238 -- Note: call Warn_On_Useless_Assignment before doing the check
4239 -- below for Is_OK_Variable_For_Out_Formal so that the setting
4240 -- of Referenced_As_LHS/Referenced_As_Out_Formal properly
a90bd866 4241 -- reflects the last assignment, not this one.
36fcf362 4242
67ce0d7e 4243 if Ekind (F) = E_Out_Parameter then
36fcf362 4244 if Warn_On_Modified_As_Out_Parameter (F)
67ce0d7e
RD		 4245 and then Is_Entity_Name (A)
4246 and then Present (Entity (A))
36fcf362 4247 and then Comes_From_Source (N)
67ce0d7e 4248 then
36fcf362 4249 Warn_On_Useless_Assignment (Entity (A), A);
67ce0d7e
RD		 4250 end if;
4251 end if;
4252
36fcf362
RD		 4253 -- Validate the form of the actual. Note that the call to
4254 -- Is_OK_Variable_For_Out_Formal generates the required
4255 -- reference in this case.
4256
0180fd26
AC		 4257 -- A call to an initialization procedure for an aggregate
4258 -- component may initialize a nested component of a constant
4259 -- designated object. In this context the object is variable.
4260
4261 if not Is_OK_Variable_For_Out_Formal (A)
4262 and then not Is_Init_Proc (Nam)
4263 then
36fcf362 4264 Error_Msg_NE ("actual for& must be a variable", A, F);
43dbd3e3 4265
3ddfabe3
AC		 4266 if Is_Subprogram (Current_Scope) then
4267 if Is_Invariant_Procedure (Current_Scope)
4268 or else Is_Partial_Invariant_Procedure (Current_Scope)
4269 then
4270 Error_Msg_N
4271 ("function used in invariant cannot modify its "
4272 & "argument", F);
4273
4274 elsif Is_Predicate_Function (Current_Scope) then
4275 Error_Msg_N
4276 ("function used in predicate cannot modify its "
4277 & "argument", F);
4278 end if;
43dbd3e3 4279 end if;
36fcf362
RD		 4280 end if;
4281
67ce0d7e 4282 -- What's the following about???
fbf5a39b
AC		 4283
4284 if Is_Entity_Name (A) then
4285 Kill_Checks (Entity (A));
4286 else
4287 Kill_All_Checks;
4288 end if;
4289 end if;
4290
4291 if Etype (A) = Any_Type then
4292 Set_Etype (N, Any_Type);
4293 return;
4294 end if;
4295
5f6fb720 4296 -- Apply appropriate constraint/predicate checks for IN [OUT] case
996ae0b0 4297
8a95f4e8 4298 if Ekind_In (F, E_In_Parameter, E_In_Out_Parameter) then
48f91b44 4299
5f6fb720
AC		 4300 -- Apply predicate tests except in certain special cases. Note
4301 -- that it might be more consistent to apply these only when
4302 -- expansion is active (in Exp_Ch6.Expand_Actuals), as we do
6eca51ce
ES		 4303 -- for the outbound predicate tests ??? In any case indicate
4304 -- the function being called, for better warnings if the call
4305 -- leads to an infinite recursion.
48f91b44 4306
b8e6830b 4307 if Predicate_Tests_On_Arguments (Nam) then
6eca51ce 4308 Apply_Predicate_Check (A, F_Typ, Nam);
48f91b44
RD		 4309 end if;
4310
4311 -- Apply required constraint checks
4312
5f6fb720
AC		 4313 -- Gigi looks at the check flag and uses the appropriate types.
4314 -- For now since one flag is used there is an optimization
4315 -- which might not be done in the IN OUT case since Gigi does
4316 -- not do any analysis. More thought required about this ???
4317
4318 -- In fact is this comment obsolete??? doesn't the expander now
4319 -- generate all these tests anyway???
4320
996ae0b0
RK		 4321 if Is_Scalar_Type (Etype (A)) then
4322 Apply_Scalar_Range_Check (A, F_Typ);
4323
4324 elsif Is_Array_Type (Etype (A)) then
4325 Apply_Length_Check (A, F_Typ);
4326
4327 elsif Is_Record_Type (F_Typ)
4328 and then Has_Discriminants (F_Typ)
4329 and then Is_Constrained (F_Typ)
4330 and then (not Is_Derived_Type (F_Typ)
19fb051c 4331 or else Comes_From_Source (Nam))
996ae0b0
RK		 4332 then
4333 Apply_Discriminant_Check (A, F_Typ);
4334
f1bd0415
AC		 4335 -- For view conversions of a discriminated object, apply
4336 -- check to object itself, the conversion alreay has the
4337 -- proper type.
4338
4339 if Nkind (A) = N_Type_Conversion
4340 and then Is_Constrained (Etype (Expression (A)))
4341 then
4342 Apply_Discriminant_Check (Expression (A), F_Typ);
4343 end if;
4344
996ae0b0
RK		 4345 elsif Is_Access_Type (F_Typ)
4346 and then Is_Array_Type (Designated_Type (F_Typ))
4347 and then Is_Constrained (Designated_Type (F_Typ))
4348 then
4349 Apply_Length_Check (A, F_Typ);
4350
4351 elsif Is_Access_Type (F_Typ)
4352 and then Has_Discriminants (Designated_Type (F_Typ))
4353 and then Is_Constrained (Designated_Type (F_Typ))
4354 then
4355 Apply_Discriminant_Check (A, F_Typ);
4356
4357 else
4358 Apply_Range_Check (A, F_Typ);
4359 end if;
2820d220 4360
0f1a6a0b
AC		 4361 -- Ada 2005 (AI-231): Note that the controlling parameter case
4362 -- already existed in Ada 95, which is partially checked
4363 -- elsewhere (see Checks), and we don't want the warning
4364 -- message to differ.
2820d220 4365
0f1a6a0b 4366 if Is_Access_Type (F_Typ)
1420b484 4367 and then Can_Never_Be_Null (F_Typ)
aa5147f0 4368 and then Known_Null (A)
2820d220 4369 then
0f1a6a0b
AC		 4370 if Is_Controlling_Formal (F) then
4371 Apply_Compile_Time_Constraint_Error
4372 (N => A,
324ac540 4373 Msg => "null value not allowed here??",
0f1a6a0b
AC		 4374 Reason => CE_Access_Check_Failed);
4375
4376 elsif Ada_Version >= Ada_2005 then
4377 Apply_Compile_Time_Constraint_Error
4378 (N => A,
4379 Msg => "(Ada 2005) null not allowed in "
324ac540 4380 & "null-excluding formal??",
0f1a6a0b
AC		 4381 Reason => CE_Null_Not_Allowed);
4382 end if;
2820d220 4383 end if;
996ae0b0
RK		 4384 end if;
4385
5f6fb720
AC		 4386 -- Checks for OUT parameters and IN OUT parameters
4387
8a95f4e8 4388 if Ekind_In (F, E_Out_Parameter, E_In_Out_Parameter) then
5f6fb720 4389
27bb7941 4390 -- If there is a type conversion, make sure the return value
5f6fb720
AC		 4391 -- meets the constraints of the variable before the conversion.
4392
996ae0b0
RK		 4393 if Nkind (A) = N_Type_Conversion then
4394 if Is_Scalar_Type (A_Typ) then
4395 Apply_Scalar_Range_Check
4396 (Expression (A), Etype (Expression (A)), A_Typ);
27bb7941 4397
e4d04166
AC		 4398 -- In addition, the returned value of the parameter must
4399 -- satisfy the bounds of the object type (see comment
4400 -- below).
27bb7941
AC		 4401
4402 Apply_Scalar_Range_Check (A, A_Typ, F_Typ);
4403
996ae0b0
RK		 4404 else
4405 Apply_Range_Check
4406 (Expression (A), Etype (Expression (A)), A_Typ);
4407 end if;
4408
27bb7941
AC		 4409 -- If no conversion, apply scalar range checks and length check
4410 -- based on the subtype of the actual (NOT that of the formal).
4411 -- This indicates that the check takes place on return from the
4412 -- call. During expansion the required constraint checks are
4413 -- inserted. In GNATprove mode, in the absence of expansion,
4414 -- the flag indicates that the returned value is valid.
5f6fb720 4415
996ae0b0
RK		 4416 else
4417 if Is_Scalar_Type (F_Typ) then
4418 Apply_Scalar_Range_Check (A, A_Typ, F_Typ);
27bb7941 4419
996ae0b0
RK		 4420 elsif Is_Array_Type (F_Typ)
4421 and then Ekind (F) = E_Out_Parameter
4422 then
4423 Apply_Length_Check (A, F_Typ);
996ae0b0
RK		 4424 else
4425 Apply_Range_Check (A, A_Typ, F_Typ);
4426 end if;
4427 end if;
5f6fb720
AC		 4428
4429 -- Note: we do not apply the predicate checks for the case of
4430 -- OUT and IN OUT parameters. They are instead applied in the
4431 -- Expand_Actuals routine in Exp_Ch6.
996ae0b0
RK		 4432 end if;
4433
4434 -- An actual associated with an access parameter is implicitly
45fc7ddb
HK		 4435 -- converted to the anonymous access type of the formal and must
4436 -- satisfy the legality checks for access conversions.
996ae0b0
RK		 4437
4438 if Ekind (F_Typ) = E_Anonymous_Access_Type then
4439 if not Valid_Conversion (A, F_Typ, A) then
4440 Error_Msg_N
4441 ("invalid implicit conversion for access parameter", A);
4442 end if;
de94a7e7
AC		 4443
4444 -- If the actual is an access selected component of a variable,
4445 -- the call may modify its designated object. It is reasonable
4446 -- to treat this as a potential modification of the enclosing
4447 -- record, to prevent spurious warnings that it should be
4448 -- declared as a constant, because intuitively programmers
4449 -- regard the designated subcomponent as part of the record.
4450
4451 if Nkind (A) = N_Selected_Component
4452 and then Is_Entity_Name (Prefix (A))
4453 and then not Is_Constant_Object (Entity (Prefix (A)))
4454 then
4455 Note_Possible_Modification (A, Sure => False);
4456 end if;
996ae0b0
RK		 4457 end if;
4458
4459 -- Check bad case of atomic/volatile argument (RM C.6(12))
4460
4461 if Is_By_Reference_Type (Etype (F))
4462 and then Comes_From_Source (N)
4463 then
4464 if Is_Atomic_Object (A)
4465 and then not Is_Atomic (Etype (F))
4466 then
b5bf3335
AC		 4467 Error_Msg_NE
4468 ("cannot pass atomic argument to non-atomic formal&",
4469 A, F);
996ae0b0
RK		 4470
4471 elsif Is_Volatile_Object (A)
4472 and then not Is_Volatile (Etype (F))
4473 then
b5bf3335
AC		 4474 Error_Msg_NE
4475 ("cannot pass volatile argument to non-volatile formal&",
4476 A, F);
996ae0b0
RK		 4477 end if;
4478 end if;
4479
4480 -- Check that subprograms don't have improper controlling
d81b4bfe 4481 -- arguments (RM 3.9.2 (9)).
996ae0b0 4482
0669bebe
GB		 4483 -- A primitive operation may have an access parameter of an
4484 -- incomplete tagged type, but a dispatching call is illegal
4485 -- if the type is still incomplete.
4486
996ae0b0
RK		 4487 if Is_Controlling_Formal (F) then
4488 Set_Is_Controlling_Actual (A);
0669bebe
GB		 4489
4490 if Ekind (Etype (F)) = E_Anonymous_Access_Type then
4491 declare
4492 Desig : constant Entity_Id := Designated_Type (Etype (F));
4493 begin
4494 if Ekind (Desig) = E_Incomplete_Type
4495 and then No (Full_View (Desig))
4496 and then No (Non_Limited_View (Desig))
4497 then
4498 Error_Msg_NE
1486a00e
AC		 4499 ("premature use of incomplete type& "
4500 & "in dispatching call", A, Desig);
0669bebe
GB		 4501 end if;
4502 end;
4503 end if;
4504
996ae0b0
RK		 4505 elsif Nkind (A) = N_Explicit_Dereference then
4506 Validate_Remote_Access_To_Class_Wide_Type (A);
4507 end if;
4508
6c802906
AC		 4509 -- Apply legality rule 3.9.2 (9/1)
4510
996ae0b0
RK		 4511 if (Is_Class_Wide_Type (A_Typ) or else Is_Dynamically_Tagged (A))
4512 and then not Is_Class_Wide_Type (F_Typ)
4513 and then not Is_Controlling_Formal (F)
6c802906 4514 and then not In_Instance
996ae0b0
RK		 4515 then
4516 Error_Msg_N ("class-wide argument not allowed here!", A);
07fc65c4 4517
b9696ffb 4518 if Is_Subprogram (Nam) and then Comes_From_Source (Nam) then
996ae0b0
RK		 4519 Error_Msg_Node_2 := F_Typ;
4520 Error_Msg_NE
82c80734 4521 ("& is not a dispatching operation of &!", A, Nam);
996ae0b0
RK		 4522 end if;
4523
97216ca8
ES		 4524 -- Apply the checks described in 3.10.2(27): if the context is a
4525 -- specific access-to-object, the actual cannot be class-wide.
4526 -- Use base type to exclude access_to_subprogram cases.
4527
996ae0b0
RK		 4528 elsif Is_Access_Type (A_Typ)
4529 and then Is_Access_Type (F_Typ)
97216ca8 4530 and then not Is_Access_Subprogram_Type (Base_Type (F_Typ))
996ae0b0 4531 and then (Is_Class_Wide_Type (Designated_Type (A_Typ))
07fc65c4
GB		 4532 or else (Nkind (A) = N_Attribute_Reference
4533 and then
2590ef12 4534 Is_Class_Wide_Type (Etype (Prefix (A)))))
996ae0b0
RK		 4535 and then not Is_Class_Wide_Type (Designated_Type (F_Typ))
4536 and then not Is_Controlling_Formal (F)
ae65d635 4537
46fe0142 4538 -- Disable these checks for call to imported C++ subprograms
ae65d635 4539
46fe0142
AC		 4540 and then not
4541 (Is_Entity_Name (Name (N))
4542 and then Is_Imported (Entity (Name (N)))
4543 and then Convention (Entity (Name (N))) = Convention_CPP)
996ae0b0
RK		 4544 then
4545 Error_Msg_N
4546 ("access to class-wide argument not allowed here!", A);
07fc65c4 4547
97216ca8 4548 if Is_Subprogram (Nam) and then Comes_From_Source (Nam) then
996ae0b0
RK		 4549 Error_Msg_Node_2 := Designated_Type (F_Typ);
4550 Error_Msg_NE
82c80734 4551 ("& is not a dispatching operation of &!", A, Nam);
996ae0b0
RK		 4552 end if;
4553 end if;
4554
f3691f46
ES		 4555 Check_Aliased_Parameter;
4556
996ae0b0
RK		 4557 Eval_Actual (A);
4558
8e4dac80 4559 -- If it is a named association, treat the selector_name as a
2590ef12 4560 -- proper identifier, and mark the corresponding entity.
996ae0b0 4561
1f9939b5 4562 if Nkind (Parent (A)) = N_Parameter_Association
2590ef12
RD		 4563
4564 -- Ignore reference in SPARK mode, as it refers to an entity not
4565 -- in scope at the point of reference, so the reference should
4566 -- be ignored for computing effects of subprograms.
4567
f5da7a97 4568 and then not GNATprove_Mode
1f9939b5 4569 then
e6b3f5ba
ES		 4570 -- If subprogram is overridden, use name of formal that
4571 -- is being called.
4572
4573 if Present (Real_Subp) then
4574 Set_Entity (Selector_Name (Parent (A)), Real_F);
4575 Set_Etype (Selector_Name (Parent (A)), Etype (Real_F));
4576
4577 else
4578 Set_Entity (Selector_Name (Parent (A)), F);
4579 Generate_Reference (F, Selector_Name (Parent (A)));
4580 Set_Etype (Selector_Name (Parent (A)), F_Typ);
4581 Generate_Reference (F_Typ, N, ' ');
4582 end if;
996ae0b0
RK		 4583 end if;
4584
4585 Prev := A;
fbf5a39b
AC		 4586
4587 if Ekind (F) /= E_Out_Parameter then
4588 Check_Unset_Reference (A);
4589 end if;
4590
fb1fdf7d 4591 -- The following checks are only relevant when SPARK_Mode is on as
7b4ebba5
AC		 4592 -- they are not standard Ada legality rule. Internally generated
4593 -- temporaries are ignored.
6c3c671e 4594
888be6b1
AC		 4595 if SPARK_Mode = On and then Comes_From_Source (A) then
4596
ed962eda 4597 -- An effectively volatile object may act as an actual when the
aafc151a 4598 -- corresponding formal is of a non-scalar effectively volatile
db7e3721 4599 -- type (SPARK RM 7.1.3(11)).
6c3c671e 4600
aafc151a
AC		 4601 if not Is_Scalar_Type (Etype (F))
4602 and then Is_Effectively_Volatile (Etype (F))
6c3c671e
AC		 4603 then
4604 null;
4605
ed962eda
AC		 4606 -- An effectively volatile object may act as an actual in a
4607 -- call to an instance of Unchecked_Conversion.
db7e3721 4608 -- (SPARK RM 7.1.3(11)).
6c3c671e
AC		 4609
4610 elsif Is_Unchecked_Conversion_Instance (Nam) then
4611 null;
4612
888be6b1
AC		 4613 -- The actual denotes an object
4614
4615 elsif Is_Effectively_Volatile_Object (A) then
6c3c671e 4616 Error_Msg_N
fb1fdf7d 4617 ("volatile object cannot act as actual in a call (SPARK "
db7e3721 4618 & "RM 7.1.3(11))", A);
888be6b1
AC		 4619
4620 -- Otherwise the actual denotes an expression. Inspect the
4621 -- expression and flag each effectively volatile object with
4622 -- enabled property Async_Writers or Effective_Reads as illegal
4623 -- because it apprears within an interfering context. Note that
4624 -- this is usually done in Resolve_Entity_Name, but when the
4625 -- effectively volatile object appears as an actual in a call,
4626 -- the call must be resolved first.
4627
4628 else
4629 Flag_Effectively_Volatile_Objects (A);
6c3c671e 4630 end if;
97779c34
AC		 4631
4632 -- Detect an external variable with an enabled property that
4633 -- does not match the mode of the corresponding formal in a
7b4ebba5
AC		 4634 -- procedure call. Functions are not considered because they
4635 -- cannot have effectively volatile formal parameters in the
4636 -- first place.
97779c34
AC		 4637
4638 if Ekind (Nam) = E_Procedure
de4ac038 4639 and then Ekind (F) = E_In_Parameter
97779c34
AC		 4640 and then Is_Entity_Name (A)
4641 and then Present (Entity (A))
4642 and then Ekind (Entity (A)) = E_Variable
4643 then
4644 A_Id := Entity (A);
4645
de4ac038
AC		 4646 if Async_Readers_Enabled (A_Id) then
4647 Property_Error (A, A_Id, Name_Async_Readers);
4648 elsif Effective_Reads_Enabled (A_Id) then
4649 Property_Error (A, A_Id, Name_Effective_Reads);
4650 elsif Effective_Writes_Enabled (A_Id) then
4651 Property_Error (A, A_Id, Name_Effective_Writes);
97779c34
AC		 4652 end if;
4653 end if;
6c3c671e
AC		 4654 end if;
4655
039538bc
AC		 4656 -- A formal parameter of a specific tagged type whose related
4657 -- subprogram is subject to pragma Extensions_Visible with value
4658 -- "False" cannot act as an actual in a subprogram with value
b3407ce0 4659 -- "True" (SPARK RM 6.1.7(3)).
039538bc
AC		 4660
4661 if Is_EVF_Expression (A)
4662 and then Extensions_Visible_Status (Nam) =
4663 Extensions_Visible_True
4664 then
4665 Error_Msg_N
44900051
AC		 4666 ("formal parameter cannot act as actual parameter when "
4667 & "Extensions_Visible is False", A);
039538bc
AC		 4668 Error_Msg_NE
4669 ("\subprogram & has Extensions_Visible True", A, Nam);
4670 end if;
4671
3c756b76 4672 -- The actual parameter of a Ghost subprogram whose formal is of
4179af27 4673 -- mode IN OUT or OUT must be a Ghost variable (SPARK RM 6.9(12)).
3c756b76 4674
95fef24f
AC		 4675 if Comes_From_Source (Nam)
4676 and then Is_Ghost_Entity (Nam)
3c756b76
AC		 4677 and then Ekind_In (F, E_In_Out_Parameter, E_Out_Parameter)
4678 and then Is_Entity_Name (A)
4679 and then Present (Entity (A))
4680 and then not Is_Ghost_Entity (Entity (A))
4681 then
4682 Error_Msg_NE
4683 ("non-ghost variable & cannot appear as actual in call to "
4684 & "ghost procedure", A, Entity (A));
4685
4686 if Ekind (F) = E_In_Out_Parameter then
4687 Error_Msg_N ("\corresponding formal has mode `IN OUT`", A);
4688 else
4689 Error_Msg_N ("\corresponding formal has mode OUT", A);
4690 end if;
4691 end if;
4692
996ae0b0
RK		 4693 Next_Actual (A);
4694
fbf5a39b
AC		 4695 -- Case where actual is not present
4696
996ae0b0
RK		 4697 else
4698 Insert_Default;
4699 end if;
4700
4701 Next_Formal (F);
4d6a38a5
ES		 4702
4703 if Present (Real_Subp) then
4704 Next_Formal (Real_F);
4705 end if;
996ae0b0 4706 end loop;
996ae0b0
RK		 4707 end Resolve_Actuals;
4708
4709 -----------------------
4710 -- Resolve_Allocator --
4711 -----------------------
4712
4713 procedure Resolve_Allocator (N : Node_Id; Typ : Entity_Id) is
949a18cc 4714 Desig_T : constant Entity_Id := Designated_Type (Typ);
ee2e3f6b 4715 E : constant Node_Id := Expression (N);
996ae0b0
RK		 4716 Subtyp : Entity_Id;
4717 Discrim : Entity_Id;
4718 Constr : Node_Id;
b7d1f17f
HK		 4719 Aggr : Node_Id;
4720 Assoc : Node_Id := Empty;
996ae0b0
RK		 4721 Disc_Exp : Node_Id;
4722
b7d1f17f
HK		 4723 procedure Check_Allocator_Discrim_Accessibility
4724 (Disc_Exp : Node_Id;
4725 Alloc_Typ : Entity_Id);
4726 -- Check that accessibility level associated with an access discriminant
4727 -- initialized in an allocator by the expression Disc_Exp is not deeper
4728 -- than the level of the allocator type Alloc_Typ. An error message is
4729 -- issued if this condition is violated. Specialized checks are done for
4730 -- the cases of a constraint expression which is an access attribute or
4731 -- an access discriminant.
4732
07fc65c4 4733 function In_Dispatching_Context return Boolean;
b7d1f17f
HK		 4734 -- If the allocator is an actual in a call, it is allowed to be class-
4735 -- wide when the context is not because it is a controlling actual.
4736
b7d1f17f
HK		 4737 -------------------------------------------
4738 -- Check_Allocator_Discrim_Accessibility --
4739 -------------------------------------------
4740
4741 procedure Check_Allocator_Discrim_Accessibility
4742 (Disc_Exp : Node_Id;
4743 Alloc_Typ : Entity_Id)
4744 is
4745 begin
4746 if Type_Access_Level (Etype (Disc_Exp)) >
f460d8f3 4747 Deepest_Type_Access_Level (Alloc_Typ)
b7d1f17f
HK		 4748 then
4749 Error_Msg_N
4750 ("operand type has deeper level than allocator type", Disc_Exp);
4751
4752 -- When the expression is an Access attribute the level of the prefix
4753 -- object must not be deeper than that of the allocator's type.
4754
4755 elsif Nkind (Disc_Exp) = N_Attribute_Reference
83e5da69
AC		 4756 and then Get_Attribute_Id (Attribute_Name (Disc_Exp)) =
4757 Attribute_Access
4758 and then Object_Access_Level (Prefix (Disc_Exp)) >
4759 Deepest_Type_Access_Level (Alloc_Typ)
b7d1f17f
HK		 4760 then
4761 Error_Msg_N
4762 ("prefix of attribute has deeper level than allocator type",
4763 Disc_Exp);
4764
4765 -- When the expression is an access discriminant the check is against
4766 -- the level of the prefix object.
4767
4768 elsif Ekind (Etype (Disc_Exp)) = E_Anonymous_Access_Type
4769 and then Nkind (Disc_Exp) = N_Selected_Component
83e5da69
AC		 4770 and then Object_Access_Level (Prefix (Disc_Exp)) >
4771 Deepest_Type_Access_Level (Alloc_Typ)
b7d1f17f
HK		 4772 then
4773 Error_Msg_N
4774 ("access discriminant has deeper level than allocator type",
4775 Disc_Exp);
4776
4777 -- All other cases are legal
4778
4779 else
4780 null;
4781 end if;
4782 end Check_Allocator_Discrim_Accessibility;
07fc65c4
GB		 4783
4784 ----------------------------
4785 -- In_Dispatching_Context --
4786 ----------------------------
4787
4788 function In_Dispatching_Context return Boolean is
4789 Par : constant Node_Id := Parent (N);
b7d1f17f
HK		 4790
4791 begin
d3b00ce3
AC		 4792 return Nkind (Par) in N_Subprogram_Call
4793 and then Is_Entity_Name (Name (Par))
4794 and then Is_Dispatching_Operation (Entity (Name (Par)));
df3e68b1 4795 end In_Dispatching_Context;
b7d1f17f 4796
07fc65c4
GB		 4797 -- Start of processing for Resolve_Allocator
4798
996ae0b0
RK		 4799 begin
4800 -- Replace general access with specific type
4801
4802 if Ekind (Etype (N)) = E_Allocator_Type then
4803 Set_Etype (N, Base_Type (Typ));
4804 end if;
4805
0669bebe 4806 if Is_Abstract_Type (Typ) then
996ae0b0
RK		 4807 Error_Msg_N ("type of allocator cannot be abstract", N);
4808 end if;
4809
2e86f679
RD		 4810 -- For qualified expression, resolve the expression using the given
4811 -- subtype (nothing to do for type mark, subtype indication)
996ae0b0
RK		 4812
4813 if Nkind (E) = N_Qualified_Expression then
4814 if Is_Class_Wide_Type (Etype (E))
949a18cc 4815 and then not Is_Class_Wide_Type (Desig_T)
07fc65c4 4816 and then not In_Dispatching_Context
996ae0b0
RK		 4817 then
4818 Error_Msg_N
4819 ("class-wide allocator not allowed for this access type", N);
4820 end if;
4821
4822 Resolve (Expression (E), Etype (E));
f3691f46 4823 Check_Non_Static_Context (Expression (E));
996ae0b0
RK		 4824 Check_Unset_Reference (Expression (E));
4825
7f54dc83
AC		 4826 -- Allocators generated by the build-in-place expansion mechanism
4827 -- are explicitly marked as coming from source but do not need to be
4828 -- checked for limited initialization. To exclude this case, ensure
4829 -- that the parent of the allocator is a source node.
4830
4831 if Is_Limited_Type (Etype (E))
4832 and then Comes_From_Source (N)
4833 and then Comes_From_Source (Parent (N))
4834 and then not In_Instance_Body
4835 then
4836 if not OK_For_Limited_Init (Etype (E), Expression (E)) then
a56886e9
AC		 4837 if Nkind (Parent (N)) = N_Assignment_Statement then
4838 Error_Msg_N
4839 ("illegal expression for initialized allocator of a "
4840 & "limited type (RM 7.5 (2.7/2))", N);
4841 else
4842 Error_Msg_N
4843 ("initialization not allowed for limited types", N);
4844 end if;
4845
7f54dc83
AC		 4846 Explain_Limited_Type (Etype (E), N);
4847 end if;
4848 end if;
4849
a56886e9
AC		 4850 -- A qualified expression requires an exact match of the type. Class-
4851 -- wide matching is not allowed.
fbf5a39b 4852
7b4db06c 4853 if (Is_Class_Wide_Type (Etype (Expression (E)))
19fb051c 4854 or else Is_Class_Wide_Type (Etype (E)))
fbf5a39b
AC		 4855 and then Base_Type (Etype (Expression (E))) /= Base_Type (Etype (E))
4856 then
4857 Wrong_Type (Expression (E), Etype (E));
4858 end if;
4859
a8551b5f
AC		 4860 -- Calls to build-in-place functions are not currently supported in
4861 -- allocators for access types associated with a simple storage pool.
4862 -- Supporting such allocators may require passing additional implicit
4863 -- parameters to build-in-place functions (or a significant revision
4864 -- of the current b-i-p implementation to unify the handling for
4865 -- multiple kinds of storage pools). ???
4866
51245e2d 4867 if Is_Limited_View (Desig_T)
a8551b5f
AC		 4868 and then Nkind (Expression (E)) = N_Function_Call
4869 then
4870 declare
260359e3
AC		 4871 Pool : constant Entity_Id :=
4872 Associated_Storage_Pool (Root_Type (Typ));
a8551b5f
AC		 4873 begin
4874 if Present (Pool)
f6205414
AC		 4875 and then
4876 Present (Get_Rep_Pragma
4877 (Etype (Pool), Name_Simple_Storage_Pool_Type))
a8551b5f
AC		 4878 then
4879 Error_Msg_N
1486a00e
AC		 4880 ("limited function calls not yet supported in simple "
4881 & "storage pool allocators", Expression (E));
a8551b5f
AC		 4882 end if;
4883 end;
4884 end if;
4885
b7d1f17f
HK		 4886 -- A special accessibility check is needed for allocators that
4887 -- constrain access discriminants. The level of the type of the
4888 -- expression used to constrain an access discriminant cannot be
f3d57416 4889 -- deeper than the type of the allocator (in contrast to access
b7d1f17f
HK		 4890 -- parameters, where the level of the actual can be arbitrary).
4891
2e86f679
RD		 4892 -- We can't use Valid_Conversion to perform this check because in
4893 -- general the type of the allocator is unrelated to the type of
4894 -- the access discriminant.
b7d1f17f
HK		 4895
4896 if Ekind (Typ) /= E_Anonymous_Access_Type
4897 or else Is_Local_Anonymous_Access (Typ)
4898 then
4899 Subtyp := Entity (Subtype_Mark (E));
4900
4901 Aggr := Original_Node (Expression (E));
4902
4903 if Has_Discriminants (Subtyp)
45fc7ddb 4904 and then Nkind_In (Aggr, N_Aggregate, N_Extension_Aggregate)
b7d1f17f
HK		 4905 then
4906 Discrim := First_Discriminant (Base_Type (Subtyp));
4907
4908 -- Get the first component expression of the aggregate
4909
4910 if Present (Expressions (Aggr)) then
4911 Disc_Exp := First (Expressions (Aggr));
4912
4913 elsif Present (Component_Associations (Aggr)) then
4914 Assoc := First (Component_Associations (Aggr));
4915
4916 if Present (Assoc) then
4917 Disc_Exp := Expression (Assoc);
4918 else
4919 Disc_Exp := Empty;
4920 end if;
4921
4922 else
4923 Disc_Exp := Empty;
4924 end if;
4925
4926 while Present (Discrim) and then Present (Disc_Exp) loop
4927 if Ekind (Etype (Discrim)) = E_Anonymous_Access_Type then
4928 Check_Allocator_Discrim_Accessibility (Disc_Exp, Typ);
4929 end if;
4930
4931 Next_Discriminant (Discrim);
4932
4933 if Present (Discrim) then
4934 if Present (Assoc) then
4935 Next (Assoc);
4936 Disc_Exp := Expression (Assoc);
4937
4938 elsif Present (Next (Disc_Exp)) then
4939 Next (Disc_Exp);
4940
4941 else
4942 Assoc := First (Component_Associations (Aggr));
4943
4944 if Present (Assoc) then
4945 Disc_Exp := Expression (Assoc);
4946 else
4947 Disc_Exp := Empty;
4948 end if;
4949 end if;
4950 end if;
4951 end loop;
4952 end if;
4953 end if;
4954
996ae0b0
RK		 4955 -- For a subtype mark or subtype indication, freeze the subtype
4956
4957 else
4958 Freeze_Expression (E);
4959
4960 if Is_Access_Constant (Typ) and then not No_Initialization (N) then
4961 Error_Msg_N
4962 ("initialization required for access-to-constant allocator", N);
4963 end if;
4964
4965 -- A special accessibility check is needed for allocators that
4966 -- constrain access discriminants. The level of the type of the
b7d1f17f 4967 -- expression used to constrain an access discriminant cannot be
f3d57416 4968 -- deeper than the type of the allocator (in contrast to access
996ae0b0
RK		 4969 -- parameters, where the level of the actual can be arbitrary).
4970 -- We can't use Valid_Conversion to perform this check because
4971 -- in general the type of the allocator is unrelated to the type
b7d1f17f 4972 -- of the access discriminant.
996ae0b0
RK		 4973
4974 if Nkind (Original_Node (E)) = N_Subtype_Indication
b7d1f17f
HK		 4975 and then (Ekind (Typ) /= E_Anonymous_Access_Type
4976 or else Is_Local_Anonymous_Access (Typ))
996ae0b0
RK		 4977 then
4978 Subtyp := Entity (Subtype_Mark (Original_Node (E)));
4979
4980 if Has_Discriminants (Subtyp) then
4981 Discrim := First_Discriminant (Base_Type (Subtyp));
4982 Constr := First (Constraints (Constraint (Original_Node (E))));
996ae0b0
RK		 4983 while Present (Discrim) and then Present (Constr) loop
4984 if Ekind (Etype (Discrim)) = E_Anonymous_Access_Type then
4985 if Nkind (Constr) = N_Discriminant_Association then
4986 Disc_Exp := Original_Node (Expression (Constr));
4987 else
4988 Disc_Exp := Original_Node (Constr);
4989 end if;
4990
b7d1f17f 4991 Check_Allocator_Discrim_Accessibility (Disc_Exp, Typ);
996ae0b0 4992 end if;
b7d1f17f 4993
996ae0b0
RK		 4994 Next_Discriminant (Discrim);
4995 Next (Constr);
4996 end loop;
4997 end if;
4998 end if;
4999 end if;
5000
758c442c
GD		 5001 -- Ada 2005 (AI-344): A class-wide allocator requires an accessibility
5002 -- check that the level of the type of the created object is not deeper
5003 -- than the level of the allocator's access type, since extensions can
5004 -- now occur at deeper levels than their ancestor types. This is a
5005 -- static accessibility level check; a run-time check is also needed in
5006 -- the case of an initialized allocator with a class-wide argument (see
5007 -- Expand_Allocator_Expression).
5008
0791fbe9 5009 if Ada_Version >= Ada_2005
949a18cc 5010 and then Is_Class_Wide_Type (Desig_T)
758c442c
GD		 5011 then
5012 declare
b7d1f17f 5013 Exp_Typ : Entity_Id;
758c442c
GD		 5014
5015 begin
5016 if Nkind (E) = N_Qualified_Expression then
5017 Exp_Typ := Etype (E);
5018 elsif Nkind (E) = N_Subtype_Indication then
5019 Exp_Typ := Entity (Subtype_Mark (Original_Node (E)));
5020 else
5021 Exp_Typ := Entity (E);
5022 end if;
5023
f460d8f3 5024 if Type_Access_Level (Exp_Typ) >
83e5da69
AC		 5025 Deepest_Type_Access_Level (Typ)
5026 then
758c442c 5027 if In_Instance_Body then
43417b90 5028 Error_Msg_Warn := SPARK_Mode /= On;
1486a00e 5029 Error_Msg_N
4a28b181
AC		 5030 ("type in allocator has deeper level than "
5031 & "designated class-wide type<<", E);
5032 Error_Msg_N ("\Program_Error [<<", E);
758c442c
GD		 5033 Rewrite (N,
5034 Make_Raise_Program_Error (Sloc (N),
5035 Reason => PE_Accessibility_Check_Failed));
5036 Set_Etype (N, Typ);
aa180613
RD		 5037
5038 -- Do not apply Ada 2005 accessibility checks on a class-wide
5039 -- allocator if the type given in the allocator is a formal
5040 -- type. A run-time check will be performed in the instance.
5041
5042 elsif not Is_Generic_Type (Exp_Typ) then
1486a00e
AC		 5043 Error_Msg_N ("type in allocator has deeper level than "
5044 & "designated class-wide type", E);
758c442c
GD		 5045 end if;
5046 end if;
5047 end;
5048 end if;
5049
996ae0b0
RK		 5050 -- Check for allocation from an empty storage pool
5051
5052 if No_Pool_Assigned (Typ) then
8da337c5 5053 Error_Msg_N ("allocation from empty storage pool!", N);
1420b484 5054
5cc9353d
RD		 5055 -- If the context is an unchecked conversion, as may happen within an
5056 -- inlined subprogram, the allocator is being resolved with its own
5057 -- anonymous type. In that case, if the target type has a specific
1420b484
JM		 5058 -- storage pool, it must be inherited explicitly by the allocator type.
5059
5060 elsif Nkind (Parent (N)) = N_Unchecked_Type_Conversion
5061 and then No (Associated_Storage_Pool (Typ))
5062 then
5063 Set_Associated_Storage_Pool
5064 (Typ, Associated_Storage_Pool (Etype (Parent (N))));
996ae0b0 5065 end if;
b7d1f17f 5066
e57ab550
AC		 5067 if Ekind (Etype (N)) = E_Anonymous_Access_Type then
5068 Check_Restriction (No_Anonymous_Allocators, N);
5069 end if;
5070
6aaa0587
ES		 5071 -- Check that an allocator with task parts isn't for a nested access
5072 -- type when restriction No_Task_Hierarchy applies.
5073
5074 if not Is_Library_Level_Entity (Base_Type (Typ))
949a18cc 5075 and then Has_Task (Base_Type (Desig_T))
6aaa0587
ES		 5076 then
5077 Check_Restriction (No_Task_Hierarchy, N);
5078 end if;
5079
77a40ec1 5080 -- An illegal allocator may be rewritten as a raise Program_Error
b7d1f17f
HK		 5081 -- statement.
5082
5083 if Nkind (N) = N_Allocator then
5084
5085 -- An anonymous access discriminant is the definition of a
aa5147f0 5086 -- coextension.
b7d1f17f
HK		 5087
5088 if Ekind (Typ) = E_Anonymous_Access_Type
5089 and then Nkind (Associated_Node_For_Itype (Typ)) =
5090 N_Discriminant_Specification
5091 then
949a18cc
AC		 5092 declare
5093 Discr : constant Entity_Id :=
5094 Defining_Identifier (Associated_Node_For_Itype (Typ));
ee2e3f6b 5095
949a18cc 5096 begin
57f4c288
ES		 5097 Check_Restriction (No_Coextensions, N);
5098
5d59eef2
AC		 5099 -- Ada 2012 AI05-0052: If the designated type of the allocator
5100 -- is limited, then the allocator shall not be used to define
5101 -- the value of an access discriminant unless the discriminated
949a18cc
AC		 5102 -- type is immutably limited.
5103
5104 if Ada_Version >= Ada_2012
5105 and then Is_Limited_Type (Desig_T)
51245e2d 5106 and then not Is_Limited_View (Scope (Discr))
949a18cc
AC		 5107 then
5108 Error_Msg_N
5d59eef2
AC		 5109 ("only immutably limited types can have anonymous "
5110 & "access discriminants designating a limited type", N);
949a18cc
AC		 5111 end if;
5112 end;
5113
b7d1f17f 5114 -- Avoid marking an allocator as a dynamic coextension if it is
aa5147f0 5115 -- within a static construct.
b7d1f17f
HK		 5116
5117 if not Is_Static_Coextension (N) then
aa5147f0 5118 Set_Is_Dynamic_Coextension (N);
b7d1f17f
HK		 5119 end if;
5120
5121 -- Cleanup for potential static coextensions
5122
5123 else
aa5147f0
ES		 5124 Set_Is_Dynamic_Coextension (N, False);
5125 Set_Is_Static_Coextension (N, False);
b7d1f17f 5126 end if;
b7d1f17f 5127 end if;
d9b056ea 5128
833eaa8a 5129 -- Report a simple error: if the designated object is a local task,
14848f57
AC		 5130 -- its body has not been seen yet, and its activation will fail an
5131 -- elaboration check.
d9b056ea 5132
949a18cc
AC		 5133 if Is_Task_Type (Desig_T)
5134 and then Scope (Base_Type (Desig_T)) = Current_Scope
d9b056ea
AC		 5135 and then Is_Compilation_Unit (Current_Scope)
5136 and then Ekind (Current_Scope) = E_Package
5137 and then not In_Package_Body (Current_Scope)
5138 then
43417b90 5139 Error_Msg_Warn := SPARK_Mode /= On;
4a28b181
AC		 5140 Error_Msg_N ("cannot activate task before body seen<<", N);
5141 Error_Msg_N ("\Program_Error [<<", N);
d9b056ea 5142 end if;
14848f57 5143
7b2aafc9
HK		 5144 -- Ada 2012 (AI05-0111-3): Detect an attempt to allocate a task or a
5145 -- type with a task component on a subpool. This action must raise
5146 -- Program_Error at runtime.
14848f57
AC		 5147
5148 if Ada_Version >= Ada_2012
dfbcb149 5149 and then Nkind (N) = N_Allocator
14848f57
AC		 5150 and then Present (Subpool_Handle_Name (N))
5151 and then Has_Task (Desig_T)
5152 then
43417b90 5153 Error_Msg_Warn := SPARK_Mode /= On;
4a28b181
AC		 5154 Error_Msg_N ("cannot allocate task on subpool<<", N);
5155 Error_Msg_N ("\Program_Error [<<", N);
7b2aafc9
HK		 5156
5157 Rewrite (N,
5158 Make_Raise_Program_Error (Sloc (N),
5159 Reason => PE_Explicit_Raise));
5160 Set_Etype (N, Typ);
14848f57 5161 end if;
996ae0b0
RK		 5162 end Resolve_Allocator;
5163
5164 ---------------------------
5165 -- Resolve_Arithmetic_Op --
5166 ---------------------------
5167
5168 -- Used for resolving all arithmetic operators except exponentiation
5169
5170 procedure Resolve_Arithmetic_Op (N : Node_Id; Typ : Entity_Id) is
fbf5a39b
AC		 5171 L : constant Node_Id := Left_Opnd (N);
5172 R : constant Node_Id := Right_Opnd (N);
5173 TL : constant Entity_Id := Base_Type (Etype (L));
5174 TR : constant Entity_Id := Base_Type (Etype (R));
5175 T : Entity_Id;
5176 Rop : Node_Id;
996ae0b0
RK		 5177
5178 B_Typ : constant Entity_Id := Base_Type (Typ);
5179 -- We do the resolution using the base type, because intermediate values
5180 -- in expressions always are of the base type, not a subtype of it.
5181
aa180613
RD		 5182 function Expected_Type_Is_Any_Real (N : Node_Id) return Boolean;
5183 -- Returns True if N is in a context that expects "any real type"
5184
996ae0b0
RK		 5185 function Is_Integer_Or_Universal (N : Node_Id) return Boolean;
5186 -- Return True iff given type is Integer or universal real/integer
5187
5188 procedure Set_Mixed_Mode_Operand (N : Node_Id; T : Entity_Id);
5189 -- Choose type of integer literal in fixed-point operation to conform
5190 -- to available fixed-point type. T is the type of the other operand,
5191 -- which is needed to determine the expected type of N.
5192
5193 procedure Set_Operand_Type (N : Node_Id);
5194 -- Set operand type to T if universal
5195
aa180613
RD		 5196 -------------------------------
5197 -- Expected_Type_Is_Any_Real --
5198 -------------------------------
5199
5200 function Expected_Type_Is_Any_Real (N : Node_Id) return Boolean is
5201 begin
5202 -- N is the expression after "delta" in a fixed_point_definition;
5203 -- see RM-3.5.9(6):
5204
45fc7ddb
HK		 5205 return Nkind_In (Parent (N), N_Ordinary_Fixed_Point_Definition,
5206 N_Decimal_Fixed_Point_Definition,
aa180613
RD		 5207
5208 -- N is one of the bounds in a real_range_specification;
5209 -- see RM-3.5.7(5):
5210
45fc7ddb 5211 N_Real_Range_Specification,
aa180613
RD		 5212
5213 -- N is the expression of a delta_constraint;
5214 -- see RM-J.3(3):
5215
45fc7ddb 5216 N_Delta_Constraint);
aa180613
RD		 5217 end Expected_Type_Is_Any_Real;
5218
996ae0b0
RK		 5219 -----------------------------
5220 -- Is_Integer_Or_Universal --
5221 -----------------------------
5222
5223 function Is_Integer_Or_Universal (N : Node_Id) return Boolean is
5224 T : Entity_Id;
5225 Index : Interp_Index;
5226 It : Interp;
5227
5228 begin
5229 if not Is_Overloaded (N) then
5230 T := Etype (N);
5231 return Base_Type (T) = Base_Type (Standard_Integer)
5232 or else T = Universal_Integer
5233 or else T = Universal_Real;
5234 else
5235 Get_First_Interp (N, Index, It);
996ae0b0 5236 while Present (It.Typ) loop
996ae0b0
RK		 5237 if Base_Type (It.Typ) = Base_Type (Standard_Integer)
5238 or else It.Typ = Universal_Integer
5239 or else It.Typ = Universal_Real
5240 then
5241 return True;
5242 end if;
5243
5244 Get_Next_Interp (Index, It);
5245 end loop;
5246 end if;
5247
5248 return False;
5249 end Is_Integer_Or_Universal;
5250
5251 ----------------------------
5252 -- Set_Mixed_Mode_Operand --
5253 ----------------------------
5254
5255 procedure Set_Mixed_Mode_Operand (N : Node_Id; T : Entity_Id) is
5256 Index : Interp_Index;
5257 It : Interp;
5258
5259 begin
5260 if Universal_Interpretation (N) = Universal_Integer then
5261
5262 -- A universal integer literal is resolved as standard integer
758c442c
GD		 5263 -- except in the case of a fixed-point result, where we leave it
5264 -- as universal (to be handled by Exp_Fixd later on)
996ae0b0
RK		 5265
5266 if Is_Fixed_Point_Type (T) then
5267 Resolve (N, Universal_Integer);
5268 else
5269 Resolve (N, Standard_Integer);
5270 end if;
5271
5272 elsif Universal_Interpretation (N) = Universal_Real
5273 and then (T = Base_Type (Standard_Integer)
5274 or else T = Universal_Integer
5275 or else T = Universal_Real)
5276 then
5277 -- A universal real can appear in a fixed-type context. We resolve
5278 -- the literal with that context, even though this might raise an
5279 -- exception prematurely (the other operand may be zero).
5280
5281 Resolve (N, B_Typ);
5282
5283 elsif Etype (N) = Base_Type (Standard_Integer)
5284 and then T = Universal_Real
5285 and then Is_Overloaded (N)
5286 then
5287 -- Integer arg in mixed-mode operation. Resolve with universal
5288 -- type, in case preference rule must be applied.
5289
5290 Resolve (N, Universal_Integer);
5291
5292 elsif Etype (N) = T
5293 and then B_Typ /= Universal_Fixed
5294 then
a77842bd 5295 -- Not a mixed-mode operation, resolve with context
996ae0b0
RK		 5296
5297 Resolve (N, B_Typ);
5298
5299 elsif Etype (N) = Any_Fixed then
5300
a77842bd 5301 -- N may itself be a mixed-mode operation, so use context type
996ae0b0
RK		 5302
5303 Resolve (N, B_Typ);
5304
5305 elsif Is_Fixed_Point_Type (T)
5306 and then B_Typ = Universal_Fixed
5307 and then Is_Overloaded (N)
5308 then
5309 -- Must be (fixed * fixed) operation, operand must have one
5310 -- compatible interpretation.
5311
5312 Resolve (N, Any_Fixed);
5313
5314 elsif Is_Fixed_Point_Type (B_Typ)
2e86f679 5315 and then (T = Universal_Real or else Is_Fixed_Point_Type (T))
996ae0b0
RK		 5316 and then Is_Overloaded (N)
5317 then
5318 -- C * F(X) in a fixed context, where C is a real literal or a
5319 -- fixed-point expression. F must have either a fixed type
5320 -- interpretation or an integer interpretation, but not both.
5321
5322 Get_First_Interp (N, Index, It);
996ae0b0 5323 while Present (It.Typ) loop
996ae0b0 5324 if Base_Type (It.Typ) = Base_Type (Standard_Integer) then
996ae0b0
RK		 5325 if Analyzed (N) then
5326 Error_Msg_N ("ambiguous operand in fixed operation", N);
5327 else
5328 Resolve (N, Standard_Integer);
5329 end if;
5330
5331 elsif Is_Fixed_Point_Type (It.Typ) then
996ae0b0
RK		 5332 if Analyzed (N) then
5333 Error_Msg_N ("ambiguous operand in fixed operation", N);
5334 else
5335 Resolve (N, It.Typ);
5336 end if;
5337 end if;
5338
5339 Get_Next_Interp (Index, It);
5340 end loop;
5341
758c442c
GD		 5342 -- Reanalyze the literal with the fixed type of the context. If
5343 -- context is Universal_Fixed, we are within a conversion, leave
5344 -- the literal as a universal real because there is no usable
5345 -- fixed type, and the target of the conversion plays no role in
5346 -- the resolution.
996ae0b0 5347
0ab80019
AC		 5348 declare
5349 Op2 : Node_Id;
5350 T2 : Entity_Id;
5351
5352 begin
5353 if N = L then
5354 Op2 := R;
5355 else
5356 Op2 := L;
5357 end if;
5358
5359 if B_Typ = Universal_Fixed
5360 and then Nkind (Op2) = N_Real_Literal
5361 then
5362 T2 := Universal_Real;
5363 else
5364 T2 := B_Typ;
5365 end if;
5366
5367 Set_Analyzed (Op2, False);
5368 Resolve (Op2, T2);
5369 end;
996ae0b0 5370
b03d3f73
AC		 5371 -- A universal real conditional expression can appear in a fixed-type
5372 -- context and must be resolved with that context to facilitate the
5373 -- code generation to the backend.
5374
5375 elsif Nkind_In (N, N_Case_Expression, N_If_Expression)
5376 and then Etype (N) = Universal_Real
5377 and then Is_Fixed_Point_Type (B_Typ)
5378 then
5379 Resolve (N, B_Typ);
5380
996ae0b0 5381 else
fbf5a39b 5382 Resolve (N);
996ae0b0
RK		 5383 end if;
5384 end Set_Mixed_Mode_Operand;
5385
5386 ----------------------
5387 -- Set_Operand_Type --
5388 ----------------------
5389
5390 procedure Set_Operand_Type (N : Node_Id) is
5391 begin
5392 if Etype (N) = Universal_Integer
5393 or else Etype (N) = Universal_Real
5394 then
5395 Set_Etype (N, T);
5396 end if;
5397 end Set_Operand_Type;
5398
996ae0b0
RK		 5399 -- Start of processing for Resolve_Arithmetic_Op
5400
5401 begin
5402 if Comes_From_Source (N)
5403 and then Ekind (Entity (N)) = E_Function
5404 and then Is_Imported (Entity (N))
fbf5a39b 5405 and then Is_Intrinsic_Subprogram (Entity (N))
996ae0b0
RK		 5406 then
5407 Resolve_Intrinsic_Operator (N, Typ);
5408 return;
5409
5cc9353d
RD		 5410 -- Special-case for mixed-mode universal expressions or fixed point type
5411 -- operation: each argument is resolved separately. The same treatment
5412 -- is required if one of the operands of a fixed point operation is
5413 -- universal real, since in this case we don't do a conversion to a
5414 -- specific fixed-point type (instead the expander handles the case).
996ae0b0 5415
ddf67a1d
AC		 5416 -- Set the type of the node to its universal interpretation because
5417 -- legality checks on an exponentiation operand need the context.
5418
45fc7ddb 5419 elsif (B_Typ = Universal_Integer or else B_Typ = Universal_Real)
996ae0b0
RK		 5420 and then Present (Universal_Interpretation (L))
5421 and then Present (Universal_Interpretation (R))
5422 then
ddf67a1d 5423 Set_Etype (N, B_Typ);
996ae0b0
RK		 5424 Resolve (L, Universal_Interpretation (L));
5425 Resolve (R, Universal_Interpretation (R));
996ae0b0
RK		 5426
5427 elsif (B_Typ = Universal_Real
45fc7ddb
HK		 5428 or else Etype (N) = Universal_Fixed
5429 or else (Etype (N) = Any_Fixed
5430 and then Is_Fixed_Point_Type (B_Typ))
5431 or else (Is_Fixed_Point_Type (B_Typ)
5432 and then (Is_Integer_Or_Universal (L)
2e86f679 5433 or else
45fc7ddb
HK		 5434 Is_Integer_Or_Universal (R))))
5435 and then Nkind_In (N, N_Op_Multiply, N_Op_Divide)
996ae0b0
RK		 5436 then
5437 if TL = Universal_Integer or else TR = Universal_Integer then
5438 Check_For_Visible_Operator (N, B_Typ);
5439 end if;
5440
5cc9353d
RD		 5441 -- If context is a fixed type and one operand is integer, the other
5442 -- is resolved with the type of the context.
996ae0b0
RK		 5443
5444 if Is_Fixed_Point_Type (B_Typ)
5445 and then (Base_Type (TL) = Base_Type (Standard_Integer)
5446 or else TL = Universal_Integer)
5447 then
5448 Resolve (R, B_Typ);
5449 Resolve (L, TL);
5450
5451 elsif Is_Fixed_Point_Type (B_Typ)
5452 and then (Base_Type (TR) = Base_Type (Standard_Integer)
5453 or else TR = Universal_Integer)
5454 then
5455 Resolve (L, B_Typ);
5456 Resolve (R, TR);
5457
5458 else
5459 Set_Mixed_Mode_Operand (L, TR);
5460 Set_Mixed_Mode_Operand (R, TL);
5461 end if;
5462
45fc7ddb
HK		 5463 -- Check the rule in RM05-4.5.5(19.1/2) disallowing universal_fixed
5464 -- multiplying operators from being used when the expected type is
5465 -- also universal_fixed. Note that B_Typ will be Universal_Fixed in
5466 -- some cases where the expected type is actually Any_Real;
5467 -- Expected_Type_Is_Any_Real takes care of that case.
aa180613 5468
996ae0b0
RK		 5469 if Etype (N) = Universal_Fixed
5470 or else Etype (N) = Any_Fixed
5471 then
5472 if B_Typ = Universal_Fixed
aa180613 5473 and then not Expected_Type_Is_Any_Real (N)
45fc7ddb
HK		 5474 and then not Nkind_In (Parent (N), N_Type_Conversion,
5475 N_Unchecked_Type_Conversion)
996ae0b0 5476 then
45fc7ddb
HK		 5477 Error_Msg_N ("type cannot be determined from context!", N);
5478 Error_Msg_N ("\explicit conversion to result type required", N);
996ae0b0
RK		 5479
5480 Set_Etype (L, Any_Type);
5481 Set_Etype (R, Any_Type);
5482
5483 else
0ab80019 5484 if Ada_Version = Ada_83
45fc7ddb
HK		 5485 and then Etype (N) = Universal_Fixed
5486 and then not
5487 Nkind_In (Parent (N), N_Type_Conversion,
5488 N_Unchecked_Type_Conversion)
996ae0b0
RK		 5489 then
5490 Error_Msg_N
a921e83c
AC		 5491 ("(Ada 83) fixed-point operation needs explicit "
5492 & "conversion", N);
996ae0b0
RK		 5493 end if;
5494
aa180613 5495 -- The expected type is "any real type" in contexts like
5cc9353d 5496
aa180613 5497 -- type T is delta <universal_fixed-expression> ...
5cc9353d 5498
aa180613
RD		 5499 -- in which case we need to set the type to Universal_Real
5500 -- so that static expression evaluation will work properly.
5501
5502 if Expected_Type_Is_Any_Real (N) then
5503 Set_Etype (N, Universal_Real);
5504 else
5505 Set_Etype (N, B_Typ);
5506 end if;
996ae0b0
RK		 5507 end if;
5508
5509 elsif Is_Fixed_Point_Type (B_Typ)
5510 and then (Is_Integer_Or_Universal (L)
5511 or else Nkind (L) = N_Real_Literal
5512 or else Nkind (R) = N_Real_Literal
45fc7ddb 5513 or else Is_Integer_Or_Universal (R))
996ae0b0
RK		 5514 then
5515 Set_Etype (N, B_Typ);
5516
5517 elsif Etype (N) = Any_Fixed then
5518
5cc9353d
RD		 5519 -- If no previous errors, this is only possible if one operand is
5520 -- overloaded and the context is universal. Resolve as such.
996ae0b0
RK		 5521
5522 Set_Etype (N, B_Typ);
5523 end if;
5524
5525 else
5526 if (TL = Universal_Integer or else TL = Universal_Real)
2e86f679 5527 and then
45fc7ddb 5528 (TR = Universal_Integer or else TR = Universal_Real)
996ae0b0
RK		 5529 then
5530 Check_For_Visible_Operator (N, B_Typ);
5531 end if;
5532
5533 -- If the context is Universal_Fixed and the operands are also
5534 -- universal fixed, this is an error, unless there is only one
841dd0f5 5535 -- applicable fixed_point type (usually Duration).
996ae0b0 5536
45fc7ddb 5537 if B_Typ = Universal_Fixed and then Etype (L) = Universal_Fixed then
996ae0b0
RK		 5538 T := Unique_Fixed_Point_Type (N);
5539
5540 if T = Any_Type then
5541 Set_Etype (N, T);
5542 return;
5543 else
5544 Resolve (L, T);
5545 Resolve (R, T);
5546 end if;
5547
5548 else
5549 Resolve (L, B_Typ);
5550 Resolve (R, B_Typ);
5551 end if;
5552
5553 -- If one of the arguments was resolved to a non-universal type.
5554 -- label the result of the operation itself with the same type.
5555 -- Do the same for the universal argument, if any.
5556
5557 T := Intersect_Types (L, R);
5558 Set_Etype (N, Base_Type (T));
5559 Set_Operand_Type (L);
5560 Set_Operand_Type (R);
5561 end if;
5562
fbf5a39b 5563 Generate_Operator_Reference (N, Typ);
dec6faf1 5564 Analyze_Dimension (N);
996ae0b0
RK		 5565 Eval_Arithmetic_Op (N);
5566
2ba431e5 5567 -- In SPARK, a multiplication or division with operands of fixed point
d18bbd25 5568 -- types must be qualified or explicitly converted to identify the
2ba431e5 5569 -- result type.
b0186f71 5570
fe5d3068
YM		 5571 if (Is_Fixed_Point_Type (Etype (L))
5572 or else Is_Fixed_Point_Type (Etype (R)))
b0186f71
AC		 5573 and then Nkind_In (N, N_Op_Multiply, N_Op_Divide)
5574 and then
5575 not Nkind_In (Parent (N), N_Qualified_Expression, N_Type_Conversion)
5576 then
ce5ba43a 5577 Check_SPARK_05_Restriction
fe5d3068 5578 ("operation should be qualified or explicitly converted", N);
b0186f71
AC		 5579 end if;
5580
acad3c0a 5581 -- Set overflow and division checking bit
996ae0b0
RK		 5582
5583 if Nkind (N) in N_Op then
5584 if not Overflow_Checks_Suppressed (Etype (N)) then
fbf5a39b 5585 Enable_Overflow_Check (N);
996ae0b0
RK		 5586 end if;
5587
fbf5a39b
AC		 5588 -- Give warning if explicit division by zero
5589
45fc7ddb 5590 if Nkind_In (N, N_Op_Divide, N_Op_Rem, N_Op_Mod)
996ae0b0
RK		 5591 and then not Division_Checks_Suppressed (Etype (N))
5592 then
fbf5a39b
AC		 5593 Rop := Right_Opnd (N);
5594
5595 if Compile_Time_Known_Value (Rop)
5596 and then ((Is_Integer_Type (Etype (Rop))
780d052e
RD		 5597 and then Expr_Value (Rop) = Uint_0)
5598 or else
5599 (Is_Real_Type (Etype (Rop))
5600 and then Expr_Value_R (Rop) = Ureal_0))
fbf5a39b 5601 then
ce72a9a3 5602 -- Specialize the warning message according to the operation.
520c0201
AC		 5603 -- When SPARK_Mode is On, force a warning instead of an error
5604 -- in that case, as this likely corresponds to deactivated
5605 -- code. The following warnings are for the case
aa180613
RD		 5606
5607 case Nkind (N) is
5608 when N_Op_Divide =>
ce72a9a3
AC		 5609
5610 -- For division, we have two cases, for float division
5611 -- of an unconstrained float type, on a machine where
5612 -- Machine_Overflows is false, we don't get an exception
5613 -- at run-time, but rather an infinity or Nan. The Nan
5614 -- case is pretty obscure, so just warn about infinities.
5615
5616 if Is_Floating_Point_Type (Typ)
5617 and then not Is_Constrained (Typ)
5618 and then not Machine_Overflows_On_Target
5619 then
5620 Error_Msg_N
1486a00e
AC		 5621 ("float division by zero, may generate "
5622 & "'+'/'- infinity??", Right_Opnd (N));
ce72a9a3 5623
520c0201 5624 -- For all other cases, we get a Constraint_Error
ce72a9a3
AC		 5625
5626 else
5627 Apply_Compile_Time_Constraint_Error
324ac540 5628 (N, "division by zero??", CE_Divide_By_Zero,
520c0201
AC		 5629 Loc => Sloc (Right_Opnd (N)),
5630 Warn => SPARK_Mode = On);
ce72a9a3 5631 end if;
aa180613
RD		 5632
5633 when N_Op_Rem =>
5634 Apply_Compile_Time_Constraint_Error
324ac540 5635 (N, "rem with zero divisor??", CE_Divide_By_Zero,
520c0201
AC		 5636 Loc => Sloc (Right_Opnd (N)),
5637 Warn => SPARK_Mode = On);
aa180613
RD		 5638
5639 when N_Op_Mod =>
5640 Apply_Compile_Time_Constraint_Error
324ac540 5641 (N, "mod with zero divisor??", CE_Divide_By_Zero,
520c0201
AC		 5642 Loc => Sloc (Right_Opnd (N)),
5643 Warn => SPARK_Mode = On);
aa180613
RD		 5644
5645 -- Division by zero can only happen with division, rem,
5646 -- and mod operations.
5647
5648 when others =>
5649 raise Program_Error;
5650 end case;
fbf5a39b 5651
520c0201
AC		 5652 -- In GNATprove mode, we enable the division check so that
5653 -- GNATprove will issue a message if it cannot be proved.
5654
5655 if GNATprove_Mode then
5656 Activate_Division_Check (N);
5657 end if;
5658
fbf5a39b
AC		 5659 -- Otherwise just set the flag to check at run time
5660
5661 else
b7d1f17f 5662 Activate_Division_Check (N);
fbf5a39b 5663 end if;
996ae0b0 5664 end if;
45fc7ddb
HK		 5665
5666 -- If Restriction No_Implicit_Conditionals is active, then it is
5667 -- violated if either operand can be negative for mod, or for rem
5668 -- if both operands can be negative.
5669
7a963087 5670 if Restriction_Check_Required (No_Implicit_Conditionals)
45fc7ddb
HK		 5671 and then Nkind_In (N, N_Op_Rem, N_Op_Mod)
5672 then
5673 declare
5674 Lo : Uint;
5675 Hi : Uint;
5676 OK : Boolean;
5677
5678 LNeg : Boolean;
5679 RNeg : Boolean;
5680 -- Set if corresponding operand might be negative
5681
5682 begin
5d5e9775
AC		 5683 Determine_Range
5684 (Left_Opnd (N), OK, Lo, Hi, Assume_Valid => True);
45fc7ddb
HK		 5685 LNeg := (not OK) or else Lo < 0;
5686
5d5e9775
AC		 5687 Determine_Range
5688 (Right_Opnd (N), OK, Lo, Hi, Assume_Valid => True);
45fc7ddb
HK		 5689 RNeg := (not OK) or else Lo < 0;
5690
5d5e9775
AC		 5691 -- Check if we will be generating conditionals. There are two
5692 -- cases where that can happen, first for REM, the only case
5693 -- is largest negative integer mod -1, where the division can
5694 -- overflow, but we still have to give the right result. The
5695 -- front end generates a test for this annoying case. Here we
5696 -- just test if both operands can be negative (that's what the
5697 -- expander does, so we match its logic here).
5698
5699 -- The second case is mod where either operand can be negative.
308e6f3a 5700 -- In this case, the back end has to generate additional tests.
5d5e9775 5701
45fc7ddb 5702 if (Nkind (N) = N_Op_Rem and then (LNeg and RNeg))
2e86f679 5703 or else
45fc7ddb
HK		 5704 (Nkind (N) = N_Op_Mod and then (LNeg or RNeg))
5705 then
5706 Check_Restriction (No_Implicit_Conditionals, N);
5707 end if;
5708 end;
5709 end if;
996ae0b0
RK		 5710 end if;
5711
5712 Check_Unset_Reference (L);
5713 Check_Unset_Reference (R);
996ae0b0
RK		 5714 end Resolve_Arithmetic_Op;
5715
5716 ------------------
5717 -- Resolve_Call --
5718 ------------------
5719
5720 procedure Resolve_Call (N : Node_Id; Typ : Entity_Id) is
ee81cbe9
AC		 5721 function Same_Or_Aliased_Subprograms
5722 (S : Entity_Id;
5723 E : Entity_Id) return Boolean;
5724 -- Returns True if the subprogram entity S is the same as E or else
5725 -- S is an alias of E.
5726
001c7783
AC		 5727 ---------------------------------
5728 -- Same_Or_Aliased_Subprograms --
5729 ---------------------------------
5730
ee81cbe9
AC		 5731 function Same_Or_Aliased_Subprograms
5732 (S : Entity_Id;
5733 E : Entity_Id) return Boolean
5734 is
5735 Subp_Alias : constant Entity_Id := Alias (S);
ee81cbe9 5736 begin
b2834fbd 5737 return S = E or else (Present (Subp_Alias) and then Subp_Alias = E);
ee81cbe9
AC		 5738 end Same_Or_Aliased_Subprograms;
5739
bf0b0e5e
AC		 5740 -- Local variables
5741
5742 Loc : constant Source_Ptr := Sloc (N);
5743 Subp : constant Node_Id := Name (N);
5744 Body_Id : Entity_Id;
5745 I : Interp_Index;
5746 It : Interp;
5747 Nam : Entity_Id;
5748 Nam_Decl : Node_Id;
5749 Nam_UA : Entity_Id;
5750 Norm_OK : Boolean;
5751 Rtype : Entity_Id;
5752 Scop : Entity_Id;
5753
ee81cbe9
AC		 5754 -- Start of processing for Resolve_Call
5755
996ae0b0 5756 begin
758c442c
GD		 5757 -- The context imposes a unique interpretation with type Typ on a
5758 -- procedure or function call. Find the entity of the subprogram that
5759 -- yields the expected type, and propagate the corresponding formal
5760 -- constraints on the actuals. The caller has established that an
5761 -- interpretation exists, and emitted an error if not unique.
996ae0b0
RK		 5762
5763 -- First deal with the case of a call to an access-to-subprogram,
5764 -- dereference made explicit in Analyze_Call.
5765
5766 if Ekind (Etype (Subp)) = E_Subprogram_Type then
996ae0b0
RK		 5767 if not Is_Overloaded (Subp) then
5768 Nam := Etype (Subp);
5769
5770 else
758c442c
GD		 5771 -- Find the interpretation whose type (a subprogram type) has a
5772 -- return type that is compatible with the context. Analysis of
5773 -- the node has established that one exists.
996ae0b0 5774
996ae0b0
RK		 5775 Nam := Empty;
5776
1420b484 5777 Get_First_Interp (Subp, I, It);
996ae0b0 5778 while Present (It.Typ) loop
996ae0b0
RK		 5779 if Covers (Typ, Etype (It.Typ)) then
5780 Nam := It.Typ;
5781 exit;
5782 end if;
5783
5784 Get_Next_Interp (I, It);
5785 end loop;
5786
5787 if No (Nam) then
5788 raise Program_Error;
5789 end if;
5790 end if;
5791
5792 -- If the prefix is not an entity, then resolve it
5793
5794 if not Is_Entity_Name (Subp) then
5795 Resolve (Subp, Nam);
5796 end if;
5797
758c442c
GD		 5798 -- For an indirect call, we always invalidate checks, since we do not
5799 -- know whether the subprogram is local or global. Yes we could do
5800 -- better here, e.g. by knowing that there are no local subprograms,
aa180613 5801 -- but it does not seem worth the effort. Similarly, we kill all
758c442c 5802 -- knowledge of current constant values.
fbf5a39b
AC		 5803
5804 Kill_Current_Values;
5805
b7d1f17f
HK		 5806 -- If this is a procedure call which is really an entry call, do
5807 -- the conversion of the procedure call to an entry call. Protected
5808 -- operations use the same circuitry because the name in the call
5809 -- can be an arbitrary expression with special resolution rules.
996ae0b0 5810
45fc7ddb 5811 elsif Nkind_In (Subp, N_Selected_Component, N_Indexed_Component)
996ae0b0
RK		 5812 or else (Is_Entity_Name (Subp)
5813 and then Ekind (Entity (Subp)) = E_Entry)
5814 then
5815 Resolve_Entry_Call (N, Typ);
5816 Check_Elab_Call (N);
fbf5a39b
AC		 5817
5818 -- Kill checks and constant values, as above for indirect case
5819 -- Who knows what happens when another task is activated?
5820
5821 Kill_Current_Values;
996ae0b0
RK		 5822 return;
5823
5824 -- Normal subprogram call with name established in Resolve
5825
5826 elsif not (Is_Type (Entity (Subp))) then
5827 Nam := Entity (Subp);
e7ba564f 5828 Set_Entity_With_Checks (Subp, Nam);
fb12497d 5829
996ae0b0
RK		 5830 -- Otherwise we must have the case of an overloaded call
5831
5832 else
5833 pragma Assert (Is_Overloaded (Subp));
d81b4bfe
TQ		 5834
5835 -- Initialize Nam to prevent warning (we know it will be assigned
5836 -- in the loop below, but the compiler does not know that).
5837
5838 Nam := Empty;
996ae0b0
RK		 5839
5840 Get_First_Interp (Subp, I, It);
996ae0b0
RK		 5841 while Present (It.Typ) loop
5842 if Covers (Typ, It.Typ) then
5843 Nam := It.Nam;
e7ba564f 5844 Set_Entity_With_Checks (Subp, Nam);
996ae0b0
RK		 5845 exit;
5846 end if;
5847
5848 Get_Next_Interp (I, It);
5849 end loop;
5850 end if;
5851
c9b99571 5852 if Is_Access_Subprogram_Type (Base_Type (Etype (Nam)))
c5cec2fe
AC		 5853 and then not Is_Access_Subprogram_Type (Base_Type (Typ))
5854 and then Nkind (Subp) /= N_Explicit_Dereference
5855 and then Present (Parameter_Associations (N))
53cf4600 5856 then
66aa7643
TQ		 5857 -- The prefix is a parameterless function call that returns an access
5858 -- to subprogram. If parameters are present in the current call, add
5859 -- add an explicit dereference. We use the base type here because
5860 -- within an instance these may be subtypes.
53cf4600
ES		 5861
5862 -- The dereference is added either in Analyze_Call or here. Should
5863 -- be consolidated ???
5864
5865 Set_Is_Overloaded (Subp, False);
5866 Set_Etype (Subp, Etype (Nam));
5867 Insert_Explicit_Dereference (Subp);
5868 Nam := Designated_Type (Etype (Nam));
5869 Resolve (Subp, Nam);
5870 end if;
5871
996ae0b0
RK		 5872 -- Check that a call to Current_Task does not occur in an entry body
5873
5874 if Is_RTE (Nam, RE_Current_Task) then
5875 declare
5876 P : Node_Id;
5877
5878 begin
5879 P := N;
5880 loop
5881 P := Parent (P);
45fc7ddb
HK		 5882
5883 -- Exclude calls that occur within the default of a formal
5884 -- parameter of the entry, since those are evaluated outside
5885 -- of the body.
5886
5887 exit when No (P) or else Nkind (P) = N_Parameter_Specification;
996ae0b0 5888
aa180613
RD		 5889 if Nkind (P) = N_Entry_Body
5890 or else (Nkind (P) = N_Subprogram_Body
45fc7ddb 5891 and then Is_Entry_Barrier_Function (P))
aa180613
RD		 5892 then
5893 Rtype := Etype (N);
43417b90 5894 Error_Msg_Warn := SPARK_Mode /= On;
996ae0b0 5895 Error_Msg_NE
4a28b181 5896 ("& should not be used in entry body (RM C.7(17))<<",
996ae0b0 5897 N, Nam);
4a28b181 5898 Error_Msg_NE ("\Program_Error [<<", N, Nam);
aa180613
RD		 5899 Rewrite (N,
5900 Make_Raise_Program_Error (Loc,
5901 Reason => PE_Current_Task_In_Entry_Body));
5902 Set_Etype (N, Rtype);
e65f50ec 5903 return;
996ae0b0
RK		 5904 end if;
5905 end loop;
5906 end;
5907 end if;
5908
758c442c
GD		 5909 -- Check that a procedure call does not occur in the context of the
5910 -- entry call statement of a conditional or timed entry call. Note that
5911 -- the case of a call to a subprogram renaming of an entry will also be
5912 -- rejected. The test for N not being an N_Entry_Call_Statement is
5913 -- defensive, covering the possibility that the processing of entry
5914 -- calls might reach this point due to later modifications of the code
5915 -- above.
996ae0b0
RK		 5916
5917 if Nkind (Parent (N)) = N_Entry_Call_Alternative
5918 and then Nkind (N) /= N_Entry_Call_Statement
5919 and then Entry_Call_Statement (Parent (N)) = N
5920 then
0791fbe9 5921 if Ada_Version < Ada_2005 then
1420b484
JM		 5922 Error_Msg_N ("entry call required in select statement", N);
5923
5924 -- Ada 2005 (AI-345): If a procedure_call_statement is used
66aa7643
TQ		 5925 -- for a procedure_or_entry_call, the procedure_name or
5926 -- procedure_prefix of the procedure_call_statement shall denote
1420b484
JM		 5927 -- an entry renamed by a procedure, or (a view of) a primitive
5928 -- subprogram of a limited interface whose first parameter is
5929 -- a controlling parameter.
5930
5931 elsif Nkind (N) = N_Procedure_Call_Statement
5932 and then not Is_Renamed_Entry (Nam)
5933 and then not Is_Controlling_Limited_Procedure (Nam)
5934 then
5935 Error_Msg_N
c8ef728f 5936 ("entry call or dispatching primitive of interface required", N);
1420b484 5937 end if;
996ae0b0
RK		 5938 end if;
5939
3b8056a5
AC		 5940 -- If the SPARK_05 restriction is active, we are not allowed
5941 -- to have a call to a subprogram before we see its completion.
5942
5943 if not Has_Completion (Nam)
5944 and then Restriction_Check_Required (SPARK_05)
5945
5946 -- Don't flag strange internal calls
5947
5948 and then Comes_From_Source (N)
5949 and then Comes_From_Source (Nam)
5950
5951 -- Only flag calls in extended main source
5952
5953 and then In_Extended_Main_Source_Unit (Nam)
5954 and then In_Extended_Main_Source_Unit (N)
5955
5956 -- Exclude enumeration literals from this processing
5957
5958 and then Ekind (Nam) /= E_Enumeration_Literal
5959 then
ce5ba43a 5960 Check_SPARK_05_Restriction
3b8056a5
AC		 5961 ("call to subprogram cannot appear before its body", N);
5962 end if;
5963
66aa7643
TQ		 5964 -- Check that this is not a call to a protected procedure or entry from
5965 -- within a protected function.
fbf5a39b 5966
c92e8586 5967 Check_Internal_Protected_Use (N, Nam);
fbf5a39b 5968
2fabf41e
AC		 5969 -- Freeze the subprogram name if not in a spec-expression. Note that
5970 -- we freeze procedure calls as well as function calls. Procedure calls
5971 -- are not frozen according to the rules (RM 13.14(14)) because it is
5972 -- impossible to have a procedure call to a non-frozen procedure in
5973 -- pure Ada, but in the code that we generate in the expander, this
5974 -- rule needs extending because we can generate procedure calls that
5975 -- need freezing.
996ae0b0 5976
a429e6b3
AC		 5977 -- In Ada 2012, expression functions may be called within pre/post
5978 -- conditions of subsequent functions or expression functions. Such
dd4e47ab
AC		 5979 -- calls do not freeze when they appear within generated bodies,
5980 -- (including the body of another expression function) which would
2fabf41e 5981 -- place the freeze node in the wrong scope. An expression function
dd4e47ab
AC		 5982 -- is frozen in the usual fashion, by the appearance of a real body,
5983 -- or at the end of a declarative part.
a429e6b3 5984
2bfad6eb
HK		 5985 if Is_Entity_Name (Subp)
5986 and then not In_Spec_Expression
5987 and then not Is_Expression_Function_Or_Completion (Current_Scope)
a429e6b3 5988 and then
2bfad6eb 5989 (not Is_Expression_Function_Or_Completion (Entity (Subp))
a429e6b3
AC		 5990 or else Scope (Entity (Subp)) = Current_Scope)
5991 then
996ae0b0
RK		 5992 Freeze_Expression (Subp);
5993 end if;
5994
758c442c
GD		 5995 -- For a predefined operator, the type of the result is the type imposed
5996 -- by context, except for a predefined operation on universal fixed.
5997 -- Otherwise The type of the call is the type returned by the subprogram
5998 -- being called.
996ae0b0
RK		 5999
6000 if Is_Predefined_Op (Nam) then
996ae0b0
RK		 6001 if Etype (N) /= Universal_Fixed then
6002 Set_Etype (N, Typ);
6003 end if;
6004
758c442c
GD		 6005 -- If the subprogram returns an array type, and the context requires the
6006 -- component type of that array type, the node is really an indexing of
6007 -- the parameterless call. Resolve as such. A pathological case occurs
6008 -- when the type of the component is an access to the array type. In
be4e989c
BD		 6009 -- this case the call is truly ambiguous. If the call is to an intrinsic
6010 -- subprogram, it can't be an indexed component. This check is necessary
6011 -- because if it's Unchecked_Conversion, and we have "type T_Ptr is
6012 -- access T;" and "type T is array (...) of T_Ptr;" (i.e. an array of
6013 -- pointers to the same array), the compiler gets confused and does an
6014 -- infinite recursion.
996ae0b0 6015
0669bebe 6016 elsif (Needs_No_Actuals (Nam) or else Needs_One_Actual (Nam))
996ae0b0
RK		 6017 and then
6018 ((Is_Array_Type (Etype (Nam))
19fb051c 6019 and then Covers (Typ, Component_Type (Etype (Nam))))
84f80f5b
AC		 6020 or else
6021 (Is_Access_Type (Etype (Nam))
6022 and then Is_Array_Type (Designated_Type (Etype (Nam)))
6023 and then
be4e989c
BD		 6024 Covers (Typ, Component_Type (Designated_Type (Etype (Nam))))
6025 and then not Is_Intrinsic_Subprogram (Entity (Subp))))
996ae0b0
RK		 6026 then
6027 declare
6028 Index_Node : Node_Id;
fbf5a39b
AC		 6029 New_Subp : Node_Id;
6030 Ret_Type : constant Entity_Id := Etype (Nam);
996ae0b0
RK		 6031
6032 begin
fbf5a39b
AC		 6033 if Is_Access_Type (Ret_Type)
6034 and then Ret_Type = Component_Type (Designated_Type (Ret_Type))
6035 then
6036 Error_Msg_N
6037 ("cannot disambiguate function call and indexing", N);
6038 else
6039 New_Subp := Relocate_Node (Subp);
4bb9c7b9
AC		 6040
6041 -- The called entity may be an explicit dereference, in which
6042 -- case there is no entity to set.
6043
6044 if Nkind (New_Subp) /= N_Explicit_Dereference then
6045 Set_Entity (Subp, Nam);
6046 end if;
fbf5a39b 6047
7205254b 6048 if (Is_Array_Type (Ret_Type)
5d5e9775 6049 and then Component_Type (Ret_Type) /= Any_Type)
7205254b
JM		 6050 or else
6051 (Is_Access_Type (Ret_Type)
5d5e9775
AC		 6052 and then
6053 Component_Type (Designated_Type (Ret_Type)) /= Any_Type)
7205254b 6054 then
0669bebe
GB		 6055 if Needs_No_Actuals (Nam) then
6056
6057 -- Indexed call to a parameterless function
6058
6059 Index_Node :=
6060 Make_Indexed_Component (Loc,
fc999c5d
RD		 6061 Prefix =>
6062 Make_Function_Call (Loc, Name => New_Subp),
0669bebe
GB		 6063 Expressions => Parameter_Associations (N));
6064 else
6065 -- An Ada 2005 prefixed call to a primitive operation
6066 -- whose first parameter is the prefix. This prefix was
6067 -- prepended to the parameter list, which is actually a
3b42c566 6068 -- list of indexes. Remove the prefix in order to build
0669bebe
GB		 6069 -- the proper indexed component.
6070
6071 Index_Node :=
6072 Make_Indexed_Component (Loc,
fc999c5d 6073 Prefix =>
0669bebe 6074 Make_Function_Call (Loc,
fc999c5d 6075 Name => New_Subp,
0669bebe
GB		 6076 Parameter_Associations =>
6077 New_List
6078 (Remove_Head (Parameter_Associations (N)))),
6079 Expressions => Parameter_Associations (N));
6080 end if;
fbf5a39b 6081
74e7891f
RD		 6082 -- Preserve the parenthesis count of the node
6083
6084 Set_Paren_Count (Index_Node, Paren_Count (N));
6085
fbf5a39b
AC		 6086 -- Since we are correcting a node classification error made
6087 -- by the parser, we call Replace rather than Rewrite.
6088
6089 Replace (N, Index_Node);
74e7891f 6090
fbf5a39b
AC		 6091 Set_Etype (Prefix (N), Ret_Type);
6092 Set_Etype (N, Typ);
6093 Resolve_Indexed_Component (N, Typ);
6094 Check_Elab_Call (Prefix (N));
6095 end if;
996ae0b0
RK		 6096 end if;
6097
6098 return;
6099 end;
6100
6101 else
6e9e35e1
AC		 6102 -- If the called function is not declared in the main unit and it
6103 -- returns the limited view of type then use the available view (as
6104 -- is done in Try_Object_Operation) to prevent back-end confusion;
7a71a7c4
AC		 6105 -- for the function entity itself. The call must appear in a context
6106 -- where the nonlimited view is available. If the function entity is
6107 -- in the extended main unit then no action is needed, because the
6108 -- back end handles this case. In either case the type of the call
6109 -- is the nonlimited view.
6110
6111 if From_Limited_With (Etype (Nam))
6112 and then Present (Available_View (Etype (Nam)))
6e9e35e1 6113 then
7a71a7c4
AC		 6114 Set_Etype (N, Available_View (Etype (Nam)));
6115
6116 if not In_Extended_Main_Code_Unit (Nam) then
6117 Set_Etype (Nam, Available_View (Etype (Nam)));
6118 end if;
fc3a3580 6119
7a71a7c4
AC		 6120 else
6121 Set_Etype (N, Etype (Nam));
6122 end if;
996ae0b0
RK		 6123 end if;
6124
6125 -- In the case where the call is to an overloaded subprogram, Analyze
6126 -- calls Normalize_Actuals once per overloaded subprogram. Therefore in
6127 -- such a case Normalize_Actuals needs to be called once more to order
6128 -- the actuals correctly. Otherwise the call will have the ordering
6129 -- given by the last overloaded subprogram whether this is the correct
6130 -- one being called or not.
6131
6132 if Is_Overloaded (Subp) then
6133 Normalize_Actuals (N, Nam, False, Norm_OK);
6134 pragma Assert (Norm_OK);
6135 end if;
6136
6137 -- In any case, call is fully resolved now. Reset Overload flag, to
6138 -- prevent subsequent overload resolution if node is analyzed again
6139
6140 Set_Is_Overloaded (Subp, False);
6141 Set_Is_Overloaded (N, False);
6142
c5cec2fe
AC		 6143 -- A Ghost entity must appear in a specific context
6144
6145 if Is_Ghost_Entity (Nam) and then Comes_From_Source (N) then
6146 Check_Ghost_Context (Nam, N);
6147 end if;
6148
758c442c
GD		 6149 -- If we are calling the current subprogram from immediately within its
6150 -- body, then that is the case where we can sometimes detect cases of
6151 -- infinite recursion statically. Do not try this in case restriction
b7d1f17f 6152 -- No_Recursion is in effect anyway, and do it only for source calls.
996ae0b0 6153
b7d1f17f
HK		 6154 if Comes_From_Source (N) then
6155 Scop := Current_Scope;
996ae0b0 6156
b2834fbd
AC		 6157 -- Check violation of SPARK_05 restriction which does not permit
6158 -- a subprogram body to contain a call to the subprogram directly.
6159
6160 if Restriction_Check_Required (SPARK_05)
6161 and then Same_Or_Aliased_Subprograms (Nam, Scop)
6162 then
ce5ba43a 6163 Check_SPARK_05_Restriction
b2834fbd
AC		 6164 ("subprogram may not contain direct call to itself", N);
6165 end if;
6166
26570b21
RD		 6167 -- Issue warning for possible infinite recursion in the absence
6168 -- of the No_Recursion restriction.
6169
ee81cbe9 6170 if Same_Or_Aliased_Subprograms (Nam, Scop)
b7d1f17f
HK		 6171 and then not Restriction_Active (No_Recursion)
6172 and then Check_Infinite_Recursion (N)
6173 then
6174 -- Here we detected and flagged an infinite recursion, so we do
da20aa43
RD		 6175 -- not need to test the case below for further warnings. Also we
6176 -- are all done if we now have a raise SE node.
996ae0b0 6177
26570b21
RD		 6178 if Nkind (N) = N_Raise_Storage_Error then
6179 return;
6180 end if;
996ae0b0 6181
26570b21
RD		 6182 -- If call is to immediately containing subprogram, then check for
6183 -- the case of a possible run-time detectable infinite recursion.
996ae0b0 6184
b7d1f17f
HK		 6185 else
6186 Scope_Loop : while Scop /= Standard_Standard loop
ee81cbe9 6187 if Same_Or_Aliased_Subprograms (Nam, Scop) then
b7d1f17f
HK		 6188
6189 -- Although in general case, recursion is not statically
6190 -- checkable, the case of calling an immediately containing
6191 -- subprogram is easy to catch.
6192
6193 Check_Restriction (No_Recursion, N);
6194
6195 -- If the recursive call is to a parameterless subprogram,
6196 -- then even if we can't statically detect infinite
6197 -- recursion, this is pretty suspicious, and we output a
6198 -- warning. Furthermore, we will try later to detect some
6199 -- cases here at run time by expanding checking code (see
6200 -- Detect_Infinite_Recursion in package Exp_Ch6).
6201
6202 -- If the recursive call is within a handler, do not emit a
6203 -- warning, because this is a common idiom: loop until input
6204 -- is correct, catch illegal input in handler and restart.
6205
6206 if No (First_Formal (Nam))
6207 and then Etype (Nam) = Standard_Void_Type
6208 and then not Error_Posted (N)
6209 and then Nkind (Parent (N)) /= N_Exception_Handler
aa180613 6210 then
b7d1f17f
HK		 6211 -- For the case of a procedure call. We give the message
6212 -- only if the call is the first statement in a sequence
6213 -- of statements, or if all previous statements are
6214 -- simple assignments. This is simply a heuristic to
6215 -- decrease false positives, without losing too many good
6216 -- warnings. The idea is that these previous statements
6217 -- may affect global variables the procedure depends on.
78efd712
AC		 6218 -- We also exclude raise statements, that may arise from
6219 -- constraint checks and are probably unrelated to the
6220 -- intended control flow.
b7d1f17f
HK		 6221
6222 if Nkind (N) = N_Procedure_Call_Statement
6223 and then Is_List_Member (N)
6224 then
6225 declare
6226 P : Node_Id;
6227 begin
6228 P := Prev (N);
6229 while Present (P) loop
fc999c5d
RD		 6230 if not Nkind_In (P, N_Assignment_Statement,
6231 N_Raise_Constraint_Error)
78efd712 6232 then
b7d1f17f
HK		 6233 exit Scope_Loop;
6234 end if;
6235
6236 Prev (P);
6237 end loop;
6238 end;
6239 end if;
6240
6241 -- Do not give warning if we are in a conditional context
6242
aa180613 6243 declare
b7d1f17f 6244 K : constant Node_Kind := Nkind (Parent (N));
aa180613 6245 begin
b7d1f17f 6246 if (K = N_Loop_Statement
b5c739f9 6247 and then Present (Iteration_Scheme (Parent (N))))
b7d1f17f
HK		 6248 or else K = N_If_Statement
6249 or else K = N_Elsif_Part
6250 or else K = N_Case_Statement_Alternative
6251 then
6252 exit Scope_Loop;
6253 end if;
aa180613 6254 end;
aa180613 6255
b7d1f17f 6256 -- Here warning is to be issued
aa180613 6257
b7d1f17f 6258 Set_Has_Recursive_Call (Nam);
43417b90 6259 Error_Msg_Warn := SPARK_Mode /= On;
4a28b181
AC		 6260 Error_Msg_N ("possible infinite recursion<<!", N);
6261 Error_Msg_N ("\Storage_Error ]<<!", N);
b7d1f17f 6262 end if;
aa180613 6263
b7d1f17f 6264 exit Scope_Loop;
996ae0b0
RK		 6265 end if;
6266
b7d1f17f
HK		 6267 Scop := Scope (Scop);
6268 end loop Scope_Loop;
6269 end if;
996ae0b0
RK		 6270 end if;
6271
b5c739f9
RD		 6272 -- Check obsolescent reference to Ada.Characters.Handling subprogram
6273
6274 Check_Obsolescent_2005_Entity (Nam, Subp);
6275
996ae0b0
RK		 6276 -- If subprogram name is a predefined operator, it was given in
6277 -- functional notation. Replace call node with operator node, so
6278 -- that actuals can be resolved appropriately.
6279
6280 if Is_Predefined_Op (Nam) or else Ekind (Nam) = E_Operator then
6281 Make_Call_Into_Operator (N, Typ, Entity (Name (N)));
6282 return;
6283
6284 elsif Present (Alias (Nam))
6285 and then Is_Predefined_Op (Alias (Nam))
6286 then
6287 Resolve_Actuals (N, Nam);
6288 Make_Call_Into_Operator (N, Typ, Alias (Nam));
6289 return;
6290 end if;
6291
fbf5a39b
AC		 6292 -- Create a transient scope if the resulting type requires it
6293
4017021b
AC		 6294 -- There are several notable exceptions:
6295
4d2907fd 6296 -- a) In init procs, the transient scope overhead is not needed, and is
4017021b
AC		 6297 -- even incorrect when the call is a nested initialization call for a
6298 -- component whose expansion may generate adjust calls. However, if the
6299 -- call is some other procedure call within an initialization procedure
6300 -- (for example a call to Create_Task in the init_proc of the task
6301 -- run-time record) a transient scope must be created around this call.
6302
4d2907fd 6303 -- b) Enumeration literal pseudo-calls need no transient scope
4017021b 6304
4d2907fd 6305 -- c) Intrinsic subprograms (Unchecked_Conversion and source info
4017021b 6306 -- functions) do not use the secondary stack even though the return
4d2907fd 6307 -- type may be unconstrained.
4017021b 6308
4d2907fd 6309 -- d) Calls to a build-in-place function, since such functions may
4017021b
AC		 6310 -- allocate their result directly in a target object, and cases where
6311 -- the result does get allocated in the secondary stack are checked for
6312 -- within the specialized Exp_Ch6 procedures for expanding those
6313 -- build-in-place calls.
6314
b5f3c913
AC		 6315 -- e) Calls to inlinable expression functions do not use the secondary
6316 -- stack (since the call will be replaced by its returned object).
6317
6318 -- f) If the subprogram is marked Inline_Always, then even if it returns
c8ef728f 6319 -- an unconstrained type the call does not require use of the secondary
45fc7ddb
HK		 6320 -- stack. However, inlining will only take place if the body to inline
6321 -- is already present. It may not be available if e.g. the subprogram is
6322 -- declared in a child instance.
c8ef728f 6323
4017021b
AC		 6324 -- If this is an initialization call for a type whose construction
6325 -- uses the secondary stack, and it is not a nested call to initialize
6326 -- a component, we do need to create a transient scope for it. We
6327 -- check for this by traversing the type in Check_Initialization_Call.
6328
c8ef728f 6329 if Is_Inlined (Nam)
84f4072a
JM		 6330 and then Has_Pragma_Inline (Nam)
6331 and then Nkind (Unit_Declaration_Node (Nam)) = N_Subprogram_Declaration
6332 and then Present (Body_To_Inline (Unit_Declaration_Node (Nam)))
c8ef728f
ES		 6333 then
6334 null;
6335
4017021b
AC		 6336 elsif Ekind (Nam) = E_Enumeration_Literal
6337 or else Is_Build_In_Place_Function (Nam)
6338 or else Is_Intrinsic_Subprogram (Nam)
b5f3c913 6339 or else Is_Inlinable_Expression_Function (Nam)
4017021b
AC		 6340 then
6341 null;
6342
4460a9bc 6343 elsif Expander_Active
996ae0b0
RK		 6344 and then Is_Type (Etype (Nam))
6345 and then Requires_Transient_Scope (Etype (Nam))
4017021b
AC		 6346 and then
6347 (not Within_Init_Proc
6348 or else
6349 (not Is_Init_Proc (Nam) and then Ekind (Nam) /= E_Function))
996ae0b0 6350 then
0669bebe 6351 Establish_Transient_Scope (N, Sec_Stack => True);
996ae0b0 6352
a9f4e3d2
AC		 6353 -- If the call appears within the bounds of a loop, it will
6354 -- be rewritten and reanalyzed, nothing left to do here.
6355
6356 if Nkind (N) /= N_Function_Call then
6357 return;
6358 end if;
6359
fbf5a39b 6360 elsif Is_Init_Proc (Nam)
996ae0b0
RK		 6361 and then not Within_Init_Proc
6362 then
6363 Check_Initialization_Call (N, Nam);
6364 end if;
6365
6366 -- A protected function cannot be called within the definition of the
88f7d2d1 6367 -- enclosing protected type, unless it is part of a pre/postcondition
ffa168bc
AC		 6368 -- on another protected operation. This may appear in the entry wrapper
6369 -- created for an entry with preconditions.
996ae0b0
RK		 6370
6371 if Is_Protected_Type (Scope (Nam))
6372 and then In_Open_Scopes (Scope (Nam))
6373 and then not Has_Completion (Scope (Nam))
88f7d2d1 6374 and then not In_Spec_Expression
9ca67d3f 6375 and then not Is_Entry_Wrapper (Current_Scope)
996ae0b0
RK		 6376 then
6377 Error_Msg_NE
6378 ("& cannot be called before end of protected definition", N, Nam);
6379 end if;
6380
6381 -- Propagate interpretation to actuals, and add default expressions
6382 -- where needed.
6383
6384 if Present (First_Formal (Nam)) then
6385 Resolve_Actuals (N, Nam);
6386
d81b4bfe
TQ		 6387 -- Overloaded literals are rewritten as function calls, for purpose of
6388 -- resolution. After resolution, we can replace the call with the
6389 -- literal itself.
996ae0b0
RK		 6390
6391 elsif Ekind (Nam) = E_Enumeration_Literal then
6392 Copy_Node (Subp, N);
6393 Resolve_Entity_Name (N, Typ);
6394
fbf5a39b 6395 -- Avoid validation, since it is a static function call
996ae0b0 6396
e65f50ec 6397 Generate_Reference (Nam, Subp);
996ae0b0
RK		 6398 return;
6399 end if;
6400
b7d1f17f
HK		 6401 -- If the subprogram is not global, then kill all saved values and
6402 -- checks. This is a bit conservative, since in many cases we could do
6403 -- better, but it is not worth the effort. Similarly, we kill constant
6404 -- values. However we do not need to do this for internal entities
6405 -- (unless they are inherited user-defined subprograms), since they
6406 -- are not in the business of molesting local values.
6407
6408 -- If the flag Suppress_Value_Tracking_On_Calls is set, then we also
6409 -- kill all checks and values for calls to global subprograms. This
6410 -- takes care of the case where an access to a local subprogram is
6411 -- taken, and could be passed directly or indirectly and then called
6412 -- from almost any context.
aa180613
RD		 6413
6414 -- Note: we do not do this step till after resolving the actuals. That
6415 -- way we still take advantage of the current value information while
6416 -- scanning the actuals.
6417
45fc7ddb
HK		 6418 -- We suppress killing values if we are processing the nodes associated
6419 -- with N_Freeze_Entity nodes. Otherwise the declaration of a tagged
6420 -- type kills all the values as part of analyzing the code that
6421 -- initializes the dispatch tables.
6422
6423 if Inside_Freezing_Actions = 0
6424 and then (not Is_Library_Level_Entity (Nam)
24357840
RD		 6425 or else Suppress_Value_Tracking_On_Call
6426 (Nearest_Dynamic_Scope (Current_Scope)))
aa180613
RD		 6427 and then (Comes_From_Source (Nam)
6428 or else (Present (Alias (Nam))
6429 and then Comes_From_Source (Alias (Nam))))
6430 then
6431 Kill_Current_Values;
6432 end if;
6433
36fcf362
RD		 6434 -- If we are warning about unread OUT parameters, this is the place to
6435 -- set Last_Assignment for OUT and IN OUT parameters. We have to do this
6436 -- after the above call to Kill_Current_Values (since that call clears
6437 -- the Last_Assignment field of all local variables).
67ce0d7e 6438
36fcf362 6439 if (Warn_On_Modified_Unread or Warn_On_All_Unread_Out_Parameters)
67ce0d7e
RD		 6440 and then Comes_From_Source (N)
6441 and then In_Extended_Main_Source_Unit (N)
6442 then
6443 declare
6444 F : Entity_Id;
6445 A : Node_Id;
6446
6447 begin
6448 F := First_Formal (Nam);
6449 A := First_Actual (N);
6450 while Present (F) and then Present (A) loop
964f13da 6451 if Ekind_In (F, E_Out_Parameter, E_In_Out_Parameter)
36fcf362 6452 and then Warn_On_Modified_As_Out_Parameter (F)
67ce0d7e
RD		 6453 and then Is_Entity_Name (A)
6454 and then Present (Entity (A))
36fcf362 6455 and then Comes_From_Source (N)
67ce0d7e
RD		 6456 and then Safe_To_Capture_Value (N, Entity (A))
6457 then
6458 Set_Last_Assignment (Entity (A), A);
6459 end if;
6460
6461 Next_Formal (F);
6462 Next_Actual (A);
6463 end loop;
6464 end;
6465 end if;
6466
996ae0b0
RK		 6467 -- If the subprogram is a primitive operation, check whether or not
6468 -- it is a correct dispatching call.
6469
6470 if Is_Overloadable (Nam)
6471 and then Is_Dispatching_Operation (Nam)
6472 then
6473 Check_Dispatching_Call (N);
6474
0669bebe
GB		 6475 elsif Ekind (Nam) /= E_Subprogram_Type
6476 and then Is_Abstract_Subprogram (Nam)
996ae0b0
RK		 6477 and then not In_Instance
6478 then
6479 Error_Msg_NE ("cannot call abstract subprogram &!", N, Nam);
6480 end if;
6481
e65f50ec
ES		 6482 -- If this is a dispatching call, generate the appropriate reference,
6483 -- for better source navigation in GPS.
6484
6485 if Is_Overloadable (Nam)
6486 and then Present (Controlling_Argument (N))
6487 then
6488 Generate_Reference (Nam, Subp, 'R');
c5d91669 6489
5cc9353d 6490 -- Normal case, not a dispatching call: generate a call reference
c5d91669 6491
e65f50ec 6492 else
9c870c90 6493 Generate_Reference (Nam, Subp, 's');
e65f50ec
ES		 6494 end if;
6495
996ae0b0
RK		 6496 if Is_Intrinsic_Subprogram (Nam) then
6497 Check_Intrinsic_Call (N);
6498 end if;
6499
5b2217f8 6500 -- Check for violation of restriction No_Specific_Termination_Handlers
dce86910 6501 -- and warn on a potentially blocking call to Abort_Task.
5b2217f8 6502
273adcdf
AC		 6503 if Restriction_Check_Required (No_Specific_Termination_Handlers)
6504 and then (Is_RTE (Nam, RE_Set_Specific_Handler)
6505 or else
6506 Is_RTE (Nam, RE_Specific_Handler))
5b2217f8
RD		 6507 then
6508 Check_Restriction (No_Specific_Termination_Handlers, N);
dce86910
AC		 6509
6510 elsif Is_RTE (Nam, RE_Abort_Task) then
6511 Check_Potentially_Blocking_Operation (N);
5b2217f8
RD		 6512 end if;
6513
806f6d37
AC		 6514 -- A call to Ada.Real_Time.Timing_Events.Set_Handler to set a relative
6515 -- timing event violates restriction No_Relative_Delay (AI-0211). We
6516 -- need to check the second argument to determine whether it is an
6517 -- absolute or relative timing event.
afbcdf5e 6518
273adcdf
AC		 6519 if Restriction_Check_Required (No_Relative_Delay)
6520 and then Is_RTE (Nam, RE_Set_Handler)
806f6d37
AC		 6521 and then Is_RTE (Etype (Next_Actual (First_Actual (N))), RE_Time_Span)
6522 then
afbcdf5e
AC		 6523 Check_Restriction (No_Relative_Delay, N);
6524 end if;
6525
21791d97
AC		 6526 -- Issue an error for a call to an eliminated subprogram. This routine
6527 -- will not perform the check if the call appears within a default
6528 -- expression.
16212e89 6529
df378148 6530 Check_For_Eliminated_Subprogram (Subp, Nam);
16212e89 6531
12f0c50c
AC		 6532 -- In formal mode, the primitive operations of a tagged type or type
6533 -- extension do not include functions that return the tagged type.
6534
f6820c2d
AC		 6535 if Nkind (N) = N_Function_Call
6536 and then Is_Tagged_Type (Etype (N))
6537 and then Is_Entity_Name (Name (N))
1a83142e 6538 and then Is_Inherited_Operation_For_Type (Entity (Name (N)), Etype (N))
f6820c2d 6539 then
ce5ba43a 6540 Check_SPARK_05_Restriction ("function not inherited", N);
f6820c2d 6541 end if;
12f0c50c 6542
e8374e7a
AC		 6543 -- Implement rule in 12.5.1 (23.3/2): In an instance, if the actual is
6544 -- class-wide and the call dispatches on result in a context that does
6545 -- not provide a tag, the call raises Program_Error.
1f6439e3
AC		 6546
6547 if Nkind (N) = N_Function_Call
6548 and then In_Instance
6549 and then Is_Generic_Actual_Type (Typ)
6550 and then Is_Class_Wide_Type (Typ)
6551 and then Has_Controlling_Result (Nam)
6552 and then Nkind (Parent (N)) = N_Object_Declaration
6553 then
e8374e7a 6554 -- Verify that none of the formals are controlling
1f6439e3
AC		 6555
6556 declare
e8374e7a 6557 Call_OK : Boolean := False;
1f6439e3
AC		 6558 F : Entity_Id;
6559
6560 begin
6561 F := First_Formal (Nam);
6562 while Present (F) loop
6563 if Is_Controlling_Formal (F) then
6564 Call_OK := True;
6565 exit;
6566 end if;
e8374e7a 6567
1f6439e3
AC		 6568 Next_Formal (F);
6569 end loop;
6570
6571 if not Call_OK then
43417b90 6572 Error_Msg_Warn := SPARK_Mode /= On;
4a28b181
AC		 6573 Error_Msg_N ("!cannot determine tag of result<<", N);
6574 Error_Msg_N ("\Program_Error [<<!", N);
1f6439e3
AC		 6575 Insert_Action (N,
6576 Make_Raise_Program_Error (Sloc (N),
6577 Reason => PE_Explicit_Raise));
6578 end if;
6579 end;
6580 end if;
6581
fc999c5d
RD		 6582 -- Check for calling a function with OUT or IN OUT parameter when the
6583 -- calling context (us right now) is not Ada 2012, so does not allow
ef2c20e7
AC		 6584 -- OUT or IN OUT parameters in function calls. Functions declared in
6585 -- a predefined unit are OK, as they may be called indirectly from a
6586 -- user-declared instantiation.
fc999c5d
RD		 6587
6588 if Ada_Version < Ada_2012
6589 and then Ekind (Nam) = E_Function
6590 and then Has_Out_Or_In_Out_Parameter (Nam)
ef2c20e7 6591 and then not In_Predefined_Unit (Nam)
fc999c5d
RD		 6592 then
6593 Error_Msg_NE ("& has at least one OUT or `IN OUT` parameter", N, Nam);
6594 Error_Msg_N ("\call to this function only allowed in Ada 2012", N);
6595 end if;
6596
0929eaeb
AC		 6597 -- Check the dimensions of the actuals in the call. For function calls,
6598 -- propagate the dimensions from the returned type to N.
6599
6600 Analyze_Dimension_Call (N, Nam);
dec6faf1 6601
67ce0d7e
RD		 6602 -- All done, evaluate call and deal with elaboration issues
6603
c01a9391 6604 Eval_Call (N);
996ae0b0 6605 Check_Elab_Call (N);
ecad37f3 6606
10671e7a
AC		 6607 -- In GNATprove mode, expansion is disabled, but we want to inline some
6608 -- subprograms to facilitate formal verification. Indirect calls through
6609 -- a subprogram type or within a generic cannot be inlined. Inlining is
6610 -- performed only for calls subject to SPARK_Mode on.
ecad37f3
ES		 6611
6612 if GNATprove_Mode
2d180af1 6613 and then SPARK_Mode = On
10671e7a
AC		 6614 and then Is_Overloadable (Nam)
6615 and then not Inside_A_Generic
ecad37f3 6616 then
bf0b0e5e
AC		 6617 Nam_UA := Ultimate_Alias (Nam);
6618 Nam_Decl := Unit_Declaration_Node (Nam_UA);
e5c4e2bc 6619
bf0b0e5e
AC		 6620 if Nkind (Nam_Decl) = N_Subprogram_Declaration then
6621 Body_Id := Corresponding_Body (Nam_Decl);
eb1ee757 6622
bf0b0e5e
AC		 6623 -- Nothing to do if the subprogram is not eligible for inlining in
6624 -- GNATprove mode.
2178830b 6625
bf0b0e5e 6626 if not Is_Inlined_Always (Nam_UA)
39521a94 6627 or else not Can_Be_Inlined_In_GNATprove_Mode (Nam_UA, Body_Id)
4bd4bb7f 6628 then
2178830b
AC		 6629 null;
6630
6631 -- Calls cannot be inlined inside assertions, as GNATprove treats
6632 -- assertions as logic expressions.
6633
6634 elsif In_Assertion_Expr /= 0 then
fd22e260
AC		 6635 Cannot_Inline
6636 ("cannot inline & (in assertion expression)?", N, Nam_UA);
4bd4bb7f 6637
3dd7e28d
YM		 6638 -- Calls cannot be inlined inside default expressions
6639
6640 elsif In_Default_Expr then
fd22e260
AC		 6641 Cannot_Inline
6642 ("cannot inline & (in default expression)?", N, Nam_UA);
3dd7e28d 6643
2178830b
AC		 6644 -- Inlining should not be performed during pre-analysis
6645
6646 elsif Full_Analysis then
6647
6648 -- With the one-pass inlining technique, a call cannot be
6649 -- inlined if the corresponding body has not been seen yet.
6650
39521a94 6651 if No (Body_Id) then
fd22e260
AC		 6652 Cannot_Inline
6653 ("cannot inline & (body not seen yet)?", N, Nam_UA);
2178830b
AC		 6654
6655 -- Nothing to do if there is no body to inline, indicating that
6656 -- the subprogram is not suitable for inlining in GNATprove
6657 -- mode.
6658
bf0b0e5e 6659 elsif No (Body_To_Inline (Nam_Decl)) then
2178830b
AC		 6660 null;
6661
fd22e260
AC		 6662 -- Do not inline calls inside expression functions, as this
6663 -- would prevent interpreting them as logical formulas in
6664 -- GNATprove.
6665
6666 elsif Present (Current_Subprogram)
6667 and then
6668 Is_Expression_Function_Or_Completion (Current_Subprogram)
6669 then
6670 Cannot_Inline
6671 ("cannot inline & (inside expression function)?",
6672 N, Nam_UA);
6673
2178830b
AC		 6674 -- Calls cannot be inlined inside potentially unevaluated
6675 -- expressions, as this would create complex actions inside
6676 -- expressions, that are not handled by GNATprove.
6677
6678 elsif Is_Potentially_Unevaluated (N) then
fd22e260
AC		 6679 Cannot_Inline
6680 ("cannot inline & (in potentially unevaluated context)?",
6681 N, Nam_UA);
2178830b 6682
3de3a1be
YM		 6683 -- Do not inline calls which would possibly lead to missing a
6684 -- type conversion check on an input parameter.
6685
6686 elsif not Call_Can_Be_Inlined_In_GNATprove_Mode (N, Nam) then
6687 Cannot_Inline
6688 ("cannot inline & (possible check on input parameters)?",
6689 N, Nam_UA);
6690
2178830b
AC		 6691 -- Otherwise, inline the call
6692
52c1498c 6693 else
eb1ee757 6694 Expand_Inlined_Call (N, Nam_UA, Nam);
52c1498c 6695 end if;
e5c4e2bc 6696 end if;
bf0b0e5e 6697 end if;
ecad37f3
ES		 6698 end if;
6699
76b84bf0 6700 Warn_On_Overlapping_Actuals (Nam, N);
996ae0b0
RK		 6701 end Resolve_Call;
6702
19d846a0
RD		 6703 -----------------------------
6704 -- Resolve_Case_Expression --
6705 -----------------------------
6706
6707 procedure Resolve_Case_Expression (N : Node_Id; Typ : Entity_Id) is
bc795e3e
YM		 6708 Alt : Node_Id;
6709 Alt_Expr : Node_Id;
6710 Alt_Typ : Entity_Id;
6711 Is_Dyn : Boolean;
19d846a0
RD		 6712
6713 begin
6714 Alt := First (Alternatives (N));
6715 while Present (Alt) loop
bc795e3e
YM		 6716 Alt_Expr := Expression (Alt);
6717 Resolve (Alt_Expr, Typ);
6718 Alt_Typ := Etype (Alt_Expr);
6719
6720 -- When the expression is of a scalar subtype different from the
6721 -- result subtype, then insert a conversion to ensure the generation
6722 -- of a constraint check.
6723
6724 if Is_Scalar_Type (Alt_Typ) and then Alt_Typ /= Typ then
6725 Rewrite (Alt_Expr, Convert_To (Typ, Alt_Expr));
6726 Analyze_And_Resolve (Alt_Expr, Typ);
6727 end if;
6728
19d846a0
RD		 6729 Next (Alt);
6730 end loop;
6731
b6dd03dd
ES		 6732 -- Apply RM 4.5.7 (17/3): whether the expression is statically or
6733 -- dynamically tagged must be known statically.
6734
6735 if Is_Tagged_Type (Typ) and then not Is_Class_Wide_Type (Typ) then
bc795e3e 6736 Alt := First (Alternatives (N));
b6dd03dd
ES		 6737 Is_Dyn := Is_Dynamically_Tagged (Expression (Alt));
6738
6739 while Present (Alt) loop
6740 if Is_Dynamically_Tagged (Expression (Alt)) /= Is_Dyn then
bc795e3e
YM		 6741 Error_Msg_N
6742 ("all or none of the dependent expressions can be "
6743 & "dynamically tagged", N);
b6dd03dd
ES		 6744 end if;
6745
6746 Next (Alt);
6747 end loop;
6748 end if;
6749
19d846a0
RD		 6750 Set_Etype (N, Typ);
6751 Eval_Case_Expression (N);
6752 end Resolve_Case_Expression;
6753
996ae0b0
RK		 6754 -------------------------------
6755 -- Resolve_Character_Literal --
6756 -------------------------------
6757
6758 procedure Resolve_Character_Literal (N : Node_Id; Typ : Entity_Id) is
6759 B_Typ : constant Entity_Id := Base_Type (Typ);
6760 C : Entity_Id;
6761
6762 begin
6763 -- Verify that the character does belong to the type of the context
6764
6765 Set_Etype (N, B_Typ);
6766 Eval_Character_Literal (N);
6767
82c80734
RD		 6768 -- Wide_Wide_Character literals must always be defined, since the set
6769 -- of wide wide character literals is complete, i.e. if a character
6770 -- literal is accepted by the parser, then it is OK for wide wide
6771 -- character (out of range character literals are rejected).
996ae0b0 6772
82c80734 6773 if Root_Type (B_Typ) = Standard_Wide_Wide_Character then
996ae0b0
RK		 6774 return;
6775
6776 -- Always accept character literal for type Any_Character, which
6777 -- occurs in error situations and in comparisons of literals, both
6778 -- of which should accept all literals.
6779
6780 elsif B_Typ = Any_Character then
6781 return;
6782
5cc9353d
RD		 6783 -- For Standard.Character or a type derived from it, check that the
6784 -- literal is in range.
996ae0b0
RK		 6785
6786 elsif Root_Type (B_Typ) = Standard_Character then
82c80734
RD		 6787 if In_Character_Range (UI_To_CC (Char_Literal_Value (N))) then
6788 return;
6789 end if;
6790
5cc9353d
RD		 6791 -- For Standard.Wide_Character or a type derived from it, check that the
6792 -- literal is in range.
82c80734
RD		 6793
6794 elsif Root_Type (B_Typ) = Standard_Wide_Character then
6795 if In_Wide_Character_Range (UI_To_CC (Char_Literal_Value (N))) then
996ae0b0
RK		 6796 return;
6797 end if;
6798
82c80734 6799 -- For Standard.Wide_Wide_Character or a type derived from it, we
159a5104 6800 -- know the literal is in range, since the parser checked.
82c80734
RD		 6801
6802 elsif Root_Type (B_Typ) = Standard_Wide_Wide_Character then
6803 return;
6804
d81b4bfe
TQ		 6805 -- If the entity is already set, this has already been resolved in a
6806 -- generic context, or comes from expansion. Nothing else to do.
996ae0b0
RK		 6807
6808 elsif Present (Entity (N)) then
6809 return;
6810
d81b4bfe
TQ		 6811 -- Otherwise we have a user defined character type, and we can use the
6812 -- standard visibility mechanisms to locate the referenced entity.
996ae0b0
RK		 6813
6814 else
6815 C := Current_Entity (N);
996ae0b0
RK		 6816 while Present (C) loop
6817 if Etype (C) = B_Typ then
e7ba564f 6818 Set_Entity_With_Checks (N, C);
996ae0b0
RK		 6819 Generate_Reference (C, N);
6820 return;
6821 end if;
6822
6823 C := Homonym (C);
6824 end loop;
6825 end if;
6826
6827 -- If we fall through, then the literal does not match any of the
5cc9353d
RD		 6828 -- entries of the enumeration type. This isn't just a constraint error
6829 -- situation, it is an illegality (see RM 4.2).
996ae0b0
RK		 6830
6831 Error_Msg_NE
6832 ("character not defined for }", N, First_Subtype (B_Typ));
996ae0b0
RK		 6833 end Resolve_Character_Literal;
6834
6835 ---------------------------
6836 -- Resolve_Comparison_Op --
6837 ---------------------------
6838
6839 -- Context requires a boolean type, and plays no role in resolution.
5cc9353d
RD		 6840 -- Processing identical to that for equality operators. The result type is
6841 -- the base type, which matters when pathological subtypes of booleans with
6842 -- limited ranges are used.
996ae0b0
RK		 6843
6844 procedure Resolve_Comparison_Op (N : Node_Id; Typ : Entity_Id) is
6845 L : constant Node_Id := Left_Opnd (N);
6846 R : constant Node_Id := Right_Opnd (N);
6847 T : Entity_Id;
6848
6849 begin
d81b4bfe
TQ		 6850 -- If this is an intrinsic operation which is not predefined, use the
6851 -- types of its declared arguments to resolve the possibly overloaded
6852 -- operands. Otherwise the operands are unambiguous and specify the
6853 -- expected type.
996ae0b0
RK		 6854
6855 if Scope (Entity (N)) /= Standard_Standard then
6856 T := Etype (First_Entity (Entity (N)));
1420b484 6857
996ae0b0
RK		 6858 else
6859 T := Find_Unique_Type (L, R);
6860
6861 if T = Any_Fixed then
6862 T := Unique_Fixed_Point_Type (L);
6863 end if;
6864 end if;
6865
fbf5a39b 6866 Set_Etype (N, Base_Type (Typ));
996ae0b0
RK		 6867 Generate_Reference (T, N, ' ');
6868
bd29d519 6869 -- Skip remaining processing if already set to Any_Type
996ae0b0 6870
bd29d519
AC		 6871 if T = Any_Type then
6872 return;
6873 end if;
6874
6875 -- Deal with other error cases
996ae0b0 6876
bd29d519
AC		 6877 if T = Any_String or else
6878 T = Any_Composite or else
6879 T = Any_Character
6880 then
6881 if T = Any_Character then
6882 Ambiguous_Character (L);
996ae0b0 6883 else
bd29d519 6884 Error_Msg_N ("ambiguous operands for comparison", N);
996ae0b0 6885 end if;
bd29d519
AC		 6886
6887 Set_Etype (N, Any_Type);
6888 return;
996ae0b0 6889 end if;
bd29d519
AC		 6890
6891 -- Resolve the operands if types OK
6892
6893 Resolve (L, T);
6894 Resolve (R, T);
6895 Check_Unset_Reference (L);
6896 Check_Unset_Reference (R);
6897 Generate_Operator_Reference (N, T);
6898 Check_Low_Bound_Tested (N);
6899
2ba431e5
YM		 6900 -- In SPARK, ordering operators <, <=, >, >= are not defined for Boolean
6901 -- types or array types except String.
b0186f71 6902
fe5d3068 6903 if Is_Boolean_Type (T) then
ce5ba43a 6904 Check_SPARK_05_Restriction
fe5d3068 6905 ("comparison is not defined on Boolean type", N);
975c6896 6906
ad05f2e9
AC		 6907 elsif Is_Array_Type (T)
6908 and then Base_Type (T) /= Standard_String
6909 then
ce5ba43a 6910 Check_SPARK_05_Restriction
ad05f2e9 6911 ("comparison is not defined on array types other than String", N);
b0186f71
AC		 6912 end if;
6913
bd29d519
AC		 6914 -- Check comparison on unordered enumeration
6915
f6636994 6916 if Bad_Unordered_Enumeration_Reference (N, Etype (L)) then
b1d12996
AC		 6917 Error_Msg_Sloc := Sloc (Etype (L));
6918 Error_Msg_NE
6919 ("comparison on unordered enumeration type& declared#?U?",
6920 N, Etype (L));
bd29d519
AC		 6921 end if;
6922
ded462b0
AC		 6923 Analyze_Dimension (N);
6924
5cc9353d 6925 -- Evaluate the relation (note we do this after the above check since
ded462b0
AC		 6926 -- this Eval call may change N to True/False. Skip this evaluation
6927 -- inside assertions, in order to keep assertions as written by users
6928 -- for tools that rely on these, e.g. GNATprove for loop invariants.
bd29d519 6929
ded462b0
AC		 6930 if In_Assertion_Expr = 0 then
6931 Eval_Relational_Op (N);
6932 end if;
996ae0b0
RK		 6933 end Resolve_Comparison_Op;
6934
996ae0b0
RK		 6935 -----------------------------------------
6936 -- Resolve_Discrete_Subtype_Indication --
6937 -----------------------------------------
6938
6939 procedure Resolve_Discrete_Subtype_Indication
6940 (N : Node_Id;
6941 Typ : Entity_Id)
6942 is
6943 R : Node_Id;
6944 S : Entity_Id;
6945
6946 begin
6947 Analyze (Subtype_Mark (N));
6948 S := Entity (Subtype_Mark (N));
6949
6950 if Nkind (Constraint (N)) /= N_Range_Constraint then
6951 Error_Msg_N ("expect range constraint for discrete type", N);
6952 Set_Etype (N, Any_Type);
6953
6954 else
6955 R := Range_Expression (Constraint (N));
5c736541
RD		 6956
6957 if R = Error then
6958 return;
6959 end if;
6960
996ae0b0
RK		 6961 Analyze (R);
6962
6963 if Base_Type (S) /= Base_Type (Typ) then
6964 Error_Msg_NE
6965 ("expect subtype of }", N, First_Subtype (Typ));
6966
6967 -- Rewrite the constraint as a range of Typ
6968 -- to allow compilation to proceed further.
6969
6970 Set_Etype (N, Typ);
6971 Rewrite (Low_Bound (R),
6972 Make_Attribute_Reference (Sloc (Low_Bound (R)),
5cc9353d 6973 Prefix => New_Occurrence_Of (Typ, Sloc (R)),
996ae0b0
RK		 6974 Attribute_Name => Name_First));
6975 Rewrite (High_Bound (R),
6976 Make_Attribute_Reference (Sloc (High_Bound (R)),
5cc9353d 6977 Prefix => New_Occurrence_Of (Typ, Sloc (R)),
996ae0b0
RK		 6978 Attribute_Name => Name_First));
6979
6980 else
6981 Resolve (R, Typ);
6982 Set_Etype (N, Etype (R));
6983
6984 -- Additionally, we must check that the bounds are compatible
6985 -- with the given subtype, which might be different from the
6986 -- type of the context.
6987
6988 Apply_Range_Check (R, S);
6989
6990 -- ??? If the above check statically detects a Constraint_Error
6991 -- it replaces the offending bound(s) of the range R with a
6992 -- Constraint_Error node. When the itype which uses these bounds
6993 -- is frozen the resulting call to Duplicate_Subexpr generates
6994 -- a new temporary for the bounds.
6995
6996 -- Unfortunately there are other itypes that are also made depend
6997 -- on these bounds, so when Duplicate_Subexpr is called they get
6998 -- a forward reference to the newly created temporaries and Gigi
6999 -- aborts on such forward references. This is probably sign of a
7000 -- more fundamental problem somewhere else in either the order of
7001 -- itype freezing or the way certain itypes are constructed.
7002
7003 -- To get around this problem we call Remove_Side_Effects right
7004 -- away if either bounds of R are a Constraint_Error.
7005
7006 declare
fbf5a39b
AC		 7007 L : constant Node_Id := Low_Bound (R);
7008 H : constant Node_Id := High_Bound (R);
996ae0b0
RK		 7009
7010 begin
7011 if Nkind (L) = N_Raise_Constraint_Error then
7012 Remove_Side_Effects (L);
7013 end if;
7014
7015 if Nkind (H) = N_Raise_Constraint_Error then
7016 Remove_Side_Effects (H);
7017 end if;
7018 end;
7019
7020 Check_Unset_Reference (Low_Bound (R));
7021 Check_Unset_Reference (High_Bound (R));
7022 end if;
7023 end if;
7024 end Resolve_Discrete_Subtype_Indication;
7025
7026 -------------------------
7027 -- Resolve_Entity_Name --
7028 -------------------------
7029
7030 -- Used to resolve identifiers and expanded names
7031
7032 procedure Resolve_Entity_Name (N : Node_Id; Typ : Entity_Id) is
a921e83c
AC		 7033 function Is_Assignment_Or_Object_Expression
7034 (Context : Node_Id;
7035 Expr : Node_Id) return Boolean;
7036 -- Determine whether node Context denotes an assignment statement or an
7037 -- object declaration whose expression is node Expr.
7038
a921e83c
AC		 7039 ----------------------------------------
7040 -- Is_Assignment_Or_Object_Expression --
7041 ----------------------------------------
7042
7043 function Is_Assignment_Or_Object_Expression
7044 (Context : Node_Id;
7045 Expr : Node_Id) return Boolean
7046 is
7047 begin
7048 if Nkind_In (Context, N_Assignment_Statement,
7049 N_Object_Declaration)
7050 and then Expression (Context) = Expr
7051 then
7052 return True;
7053
7054 -- Check whether a construct that yields a name is the expression of
7055 -- an assignment statement or an object declaration.
7056
7057 elsif (Nkind_In (Context, N_Attribute_Reference,
7058 N_Explicit_Dereference,
7059 N_Indexed_Component,
7060 N_Selected_Component,
7061 N_Slice)
7062 and then Prefix (Context) = Expr)
7063 or else
7064 (Nkind_In (Context, N_Type_Conversion,
7065 N_Unchecked_Type_Conversion)
7066 and then Expression (Context) = Expr)
7067 then
7068 return
7069 Is_Assignment_Or_Object_Expression
7070 (Context => Parent (Context),
7071 Expr => Context);
7072
7073 -- Otherwise the context is not an assignment statement or an object
7074 -- declaration.
7075
7076 else
7077 return False;
7078 end if;
7079 end Is_Assignment_Or_Object_Expression;
7080
f9966234
AC		 7081 -- Local variables
7082
7083 E : constant Entity_Id := Entity (N);
d99565f8 7084 Par : Node_Id;
f9966234
AC		 7085
7086 -- Start of processing for Resolve_Entity_Name
996ae0b0
RK		 7087
7088 begin
07fc65c4
GB		 7089 -- If garbage from errors, set to Any_Type and return
7090
7091 if No (E) and then Total_Errors_Detected /= 0 then
7092 Set_Etype (N, Any_Type);
7093 return;
7094 end if;
7095
996ae0b0
RK		 7096 -- Replace named numbers by corresponding literals. Note that this is
7097 -- the one case where Resolve_Entity_Name must reset the Etype, since
7098 -- it is currently marked as universal.
7099
7100 if Ekind (E) = E_Named_Integer then
7101 Set_Etype (N, Typ);
7102 Eval_Named_Integer (N);
7103
7104 elsif Ekind (E) = E_Named_Real then
7105 Set_Etype (N, Typ);
7106 Eval_Named_Real (N);
7107
6989bc1f
AC		 7108 -- For enumeration literals, we need to make sure that a proper style
7109 -- check is done, since such literals are overloaded, and thus we did
7110 -- not do a style check during the first phase of analysis.
7111
7112 elsif Ekind (E) = E_Enumeration_Literal then
e7ba564f 7113 Set_Entity_With_Checks (N, E);
6989bc1f
AC		 7114 Eval_Entity_Name (N);
7115
596b25f9
AC		 7116 -- Case of (sub)type name appearing in a context where an expression
7117 -- is expected. This is legal if occurrence is a current instance.
7118 -- See RM 8.6 (17/3).
996ae0b0
RK		 7119
7120 elsif Is_Type (E) then
596b25f9 7121 if Is_Current_Instance (N) then
996ae0b0 7122 null;
e606088a 7123
308e6f3a 7124 -- Any other use is an error
e606088a 7125
996ae0b0
RK		 7126 else
7127 Error_Msg_N
758c442c 7128 ("invalid use of subtype mark in expression or call", N);
996ae0b0
RK		 7129 end if;
7130
7131 -- Check discriminant use if entity is discriminant in current scope,
7132 -- i.e. discriminant of record or concurrent type currently being
7133 -- analyzed. Uses in corresponding body are unrestricted.
7134
7135 elsif Ekind (E) = E_Discriminant
7136 and then Scope (E) = Current_Scope
7137 and then not Has_Completion (Current_Scope)
7138 then
7139 Check_Discriminant_Use (N);
7140
7141 -- A parameterless generic function cannot appear in a context that
7142 -- requires resolution.
7143
7144 elsif Ekind (E) = E_Generic_Function then
7145 Error_Msg_N ("illegal use of generic function", N);
7146
a921e83c
AC		 7147 -- In Ada 83 an OUT parameter cannot be read
7148
996ae0b0 7149 elsif Ekind (E) = E_Out_Parameter
996ae0b0 7150 and then (Nkind (Parent (N)) in N_Op
a921e83c
AC		 7151 or else Nkind (Parent (N)) = N_Explicit_Dereference
7152 or else Is_Assignment_Or_Object_Expression
7153 (Context => Parent (N),
7154 Expr => N))
996ae0b0 7155 then
a921e83c
AC		 7156 if Ada_Version = Ada_83 then
7157 Error_Msg_N ("(Ada 83) illegal reading of out parameter", N);
a921e83c 7158 end if;
996ae0b0
RK		 7159
7160 -- In all other cases, just do the possible static evaluation
7161
7162 else
d81b4bfe
TQ		 7163 -- A deferred constant that appears in an expression must have a
7164 -- completion, unless it has been removed by in-place expansion of
3f8c04e7
AC		 7165 -- an aggregate. A constant that is a renaming does not need
7166 -- initialization.
996ae0b0
RK		 7167
7168 if Ekind (E) = E_Constant
7169 and then Comes_From_Source (E)
7170 and then No (Constant_Value (E))
7171 and then Is_Frozen (Etype (E))
45fc7ddb 7172 and then not In_Spec_Expression
996ae0b0 7173 and then not Is_Imported (E)
3f8c04e7 7174 and then Nkind (Parent (E)) /= N_Object_Renaming_Declaration
996ae0b0 7175 then
996ae0b0
RK		 7176 if No_Initialization (Parent (E))
7177 or else (Present (Full_View (E))
7178 and then No_Initialization (Parent (Full_View (E))))
7179 then
7180 null;
7181 else
b4213ffd
AC		 7182 Error_Msg_N
7183 ("deferred constant is frozen before completion", N);
996ae0b0
RK		 7184 end if;
7185 end if;
7186
7187 Eval_Entity_Name (N);
7188 end if;
6c3c671e 7189
d99565f8
AC		 7190 Par := Parent (N);
7191
7192 -- When the entity appears in a parameter association, retrieve the
7193 -- related subprogram call.
7194
7195 if Nkind (Par) = N_Parameter_Association then
7196 Par := Parent (Par);
7197 end if;
7198
ed37f25a 7199 if Comes_From_Source (N) then
d950f051 7200
ed37f25a
AC		 7201 -- The following checks are only relevant when SPARK_Mode is on as
7202 -- they are not standard Ada legality rules.
6c3c671e 7203
ed37f25a 7204 if SPARK_Mode = On then
c5cec2fe 7205
ed37f25a
AC		 7206 -- An effectively volatile object subject to enabled properties
7207 -- Async_Writers or Effective_Reads must appear in non-interfering
7208 -- context (SPARK RM 7.1.3(12)).
c5cec2fe 7209
ed37f25a
AC		 7210 if Is_Object (E)
7211 and then Is_Effectively_Volatile (E)
7212 and then (Async_Writers_Enabled (E)
7213 or else Effective_Reads_Enabled (E))
7214 and then not Is_OK_Volatile_Context (Par, N)
7215 then
7216 SPARK_Msg_N
7217 ("volatile object cannot appear in this context "
7218 & "(SPARK RM 7.1.3(12))", N);
7219 end if;
c5cec2fe 7220
5904016a
AC		 7221 -- Check for possible elaboration issues with respect to reads of
7222 -- variables. The act of renaming the variable is not considered a
7223 -- read as it simply establishes an alias.
ed37f25a 7224
5904016a 7225 if Ekind (E) = E_Variable
d4b56371 7226 and then Dynamic_Elaboration_Checks
5904016a
AC		 7227 and then Nkind (Par) /= N_Object_Renaming_Declaration
7228 then
ed37f25a
AC		 7229 Check_Elab_Call (N);
7230 end if;
fdc54be6
AC		 7231
7232 -- The variable may eventually become a constituent of a single
7233 -- protected/task type. Record the reference now and verify its
7234 -- legality when analyzing the contract of the variable
7235 -- (SPARK RM 9.3).
7236
7237 if Ekind (E) = E_Variable then
7238 Record_Possible_Part_Of_Reference (E, N);
7239 end if;
ed37f25a 7240 end if;
de4899bb 7241
ed37f25a 7242 -- A Ghost entity must appear in a specific context
de4899bb 7243
ed37f25a
AC		 7244 if Is_Ghost_Entity (E) then
7245 Check_Ghost_Context (E, N);
7246 end if;
de4899bb 7247 end if;
996ae0b0
RK		 7248 end Resolve_Entity_Name;
7249
7250 -------------------
7251 -- Resolve_Entry --
7252 -------------------
7253
7254 procedure Resolve_Entry (Entry_Name : Node_Id) is
7255 Loc : constant Source_Ptr := Sloc (Entry_Name);
7256 Nam : Entity_Id;
7257 New_N : Node_Id;
7258 S : Entity_Id;
7259 Tsk : Entity_Id;
7260 E_Name : Node_Id;
7261 Index : Node_Id;
7262
7263 function Actual_Index_Type (E : Entity_Id) return Entity_Id;
7264 -- If the bounds of the entry family being called depend on task
7265 -- discriminants, build a new index subtype where a discriminant is
7266 -- replaced with the value of the discriminant of the target task.
7267 -- The target task is the prefix of the entry name in the call.
7268
7269 -----------------------
7270 -- Actual_Index_Type --
7271 -----------------------
7272
7273 function Actual_Index_Type (E : Entity_Id) return Entity_Id is
fbf5a39b
AC		 7274 Typ : constant Entity_Id := Entry_Index_Type (E);
7275 Tsk : constant Entity_Id := Scope (E);
7276 Lo : constant Node_Id := Type_Low_Bound (Typ);
7277 Hi : constant Node_Id := Type_High_Bound (Typ);
996ae0b0
RK		 7278 New_T : Entity_Id;
7279
7280 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id;
7281 -- If the bound is given by a discriminant, replace with a reference
d81b4bfe
TQ		 7282 -- to the discriminant of the same name in the target task. If the
7283 -- entry name is the target of a requeue statement and the entry is
7284 -- in the current protected object, the bound to be used is the
008f6fd3 7285 -- discriminal of the object (see Apply_Range_Checks for details of
d81b4bfe 7286 -- the transformation).
996ae0b0
RK		 7287
7288 -----------------------------
7289 -- Actual_Discriminant_Ref --
7290 -----------------------------
7291
7292 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
fbf5a39b 7293 Typ : constant Entity_Id := Etype (Bound);
996ae0b0
RK		 7294 Ref : Node_Id;
7295
7296 begin
7297 Remove_Side_Effects (Bound);
7298
7299 if not Is_Entity_Name (Bound)
7300 or else Ekind (Entity (Bound)) /= E_Discriminant
7301 then
7302 return Bound;
7303
7304 elsif Is_Protected_Type (Tsk)
7305 and then In_Open_Scopes (Tsk)
7306 and then Nkind (Parent (Entry_Name)) = N_Requeue_Statement
7307 then
6ca9ec9c
AC		 7308 -- Note: here Bound denotes a discriminant of the corresponding
7309 -- record type tskV, whose discriminal is a formal of the
7310 -- init-proc tskVIP. What we want is the body discriminal,
7311 -- which is associated to the discriminant of the original
7312 -- concurrent type tsk.
7313
5a153b27
AC		 7314 return New_Occurrence_Of
7315 (Find_Body_Discriminal (Entity (Bound)), Loc);
996ae0b0
RK		 7316
7317 else
7318 Ref :=
7319 Make_Selected_Component (Loc,
7320 Prefix => New_Copy_Tree (Prefix (Prefix (Entry_Name))),
7321 Selector_Name => New_Occurrence_Of (Entity (Bound), Loc));
7322 Analyze (Ref);
7323 Resolve (Ref, Typ);
7324 return Ref;
7325 end if;
7326 end Actual_Discriminant_Ref;
7327
7328 -- Start of processing for Actual_Index_Type
7329
7330 begin
7331 if not Has_Discriminants (Tsk)
19fb051c 7332 or else (not Is_Entity_Name (Lo) and then not Is_Entity_Name (Hi))
996ae0b0
RK		 7333 then
7334 return Entry_Index_Type (E);
7335
7336 else
7337 New_T := Create_Itype (Ekind (Typ), Parent (Entry_Name));
7338 Set_Etype (New_T, Base_Type (Typ));
7339 Set_Size_Info (New_T, Typ);
7340 Set_RM_Size (New_T, RM_Size (Typ));
7341 Set_Scalar_Range (New_T,
7342 Make_Range (Sloc (Entry_Name),
7343 Low_Bound => Actual_Discriminant_Ref (Lo),
7344 High_Bound => Actual_Discriminant_Ref (Hi)));
7345
7346 return New_T;
7347 end if;
7348 end Actual_Index_Type;
7349
704228bd 7350 -- Start of processing for Resolve_Entry
996ae0b0
RK		 7351
7352 begin
5cc9353d
RD		 7353 -- Find name of entry being called, and resolve prefix of name with its
7354 -- own type. The prefix can be overloaded, and the name and signature of
7355 -- the entry must be taken into account.
996ae0b0
RK		 7356
7357 if Nkind (Entry_Name) = N_Indexed_Component then
7358
7359 -- Case of dealing with entry family within the current tasks
7360
7361 E_Name := Prefix (Entry_Name);
7362
7363 else
7364 E_Name := Entry_Name;
7365 end if;
7366
7367 if Is_Entity_Name (E_Name) then
996ae0b0 7368
d81b4bfe
TQ		 7369 -- Entry call to an entry (or entry family) in the current task. This
7370 -- is legal even though the task will deadlock. Rewrite as call to
7371 -- current task.
996ae0b0 7372
d81b4bfe
TQ		 7373 -- This can also be a call to an entry in an enclosing task. If this
7374 -- is a single task, we have to retrieve its name, because the scope
7375 -- of the entry is the task type, not the object. If the enclosing
7376 -- task is a task type, the identity of the task is given by its own
7377 -- self variable.
7378
7379 -- Finally this can be a requeue on an entry of the same task or
7380 -- protected object.
996ae0b0
RK		 7381
7382 S := Scope (Entity (E_Name));
7383
7384 for J in reverse 0 .. Scope_Stack.Last loop
996ae0b0
RK		 7385 if Is_Task_Type (Scope_Stack.Table (J).Entity)
7386 and then not Comes_From_Source (S)
7387 then
7388 -- S is an enclosing task or protected object. The concurrent
7389 -- declaration has been converted into a type declaration, and
7390 -- the object itself has an object declaration that follows
7391 -- the type in the same declarative part.
7392
7393 Tsk := Next_Entity (S);
996ae0b0
RK		 7394 while Etype (Tsk) /= S loop
7395 Next_Entity (Tsk);
7396 end loop;
7397
7398 S := Tsk;
7399 exit;
7400
7401 elsif S = Scope_Stack.Table (J).Entity then
7402
7403 -- Call to current task. Will be transformed into call to Self
7404
7405 exit;
7406
7407 end if;
7408 end loop;
7409
7410 New_N :=
7411 Make_Selected_Component (Loc,
7412 Prefix => New_Occurrence_Of (S, Loc),
7413 Selector_Name =>
7414 New_Occurrence_Of (Entity (E_Name), Loc));
7415 Rewrite (E_Name, New_N);
7416 Analyze (E_Name);
7417
7418 elsif Nkind (Entry_Name) = N_Selected_Component
7419 and then Is_Overloaded (Prefix (Entry_Name))
7420 then
d81b4bfe 7421 -- Use the entry name (which must be unique at this point) to find
5cc9353d 7422 -- the prefix that returns the corresponding task/protected type.
996ae0b0
RK		 7423
7424 declare
fbf5a39b 7425 Pref : constant Node_Id := Prefix (Entry_Name);
c8307596 7426 Ent : constant Entity_Id := Entity (Selector_Name (Entry_Name));
996ae0b0
RK		 7427 I : Interp_Index;
7428 It : Interp;
996ae0b0
RK		 7429
7430 begin
7431 Get_First_Interp (Pref, I, It);
996ae0b0 7432 while Present (It.Typ) loop
996ae0b0
RK		 7433 if Scope (Ent) = It.Typ then
7434 Set_Etype (Pref, It.Typ);
7435 exit;
7436 end if;
7437
7438 Get_Next_Interp (I, It);
7439 end loop;
7440 end;
7441 end if;
7442
7443 if Nkind (Entry_Name) = N_Selected_Component then
fbf5a39b 7444 Resolve (Prefix (Entry_Name));
996ae0b0
RK		 7445
7446 else pragma Assert (Nkind (Entry_Name) = N_Indexed_Component);
7447 Nam := Entity (Selector_Name (Prefix (Entry_Name)));
fbf5a39b 7448 Resolve (Prefix (Prefix (Entry_Name)));
c8307596 7449 Index := First (Expressions (Entry_Name));
996ae0b0
RK		 7450 Resolve (Index, Entry_Index_Type (Nam));
7451
d81b4bfe
TQ		 7452 -- Up to this point the expression could have been the actual in a
7453 -- simple entry call, and be given by a named association.
996ae0b0
RK		 7454
7455 if Nkind (Index) = N_Parameter_Association then
7456 Error_Msg_N ("expect expression for entry index", Index);
7457 else
7458 Apply_Range_Check (Index, Actual_Index_Type (Nam));
7459 end if;
7460 end if;
996ae0b0
RK		 7461 end Resolve_Entry;
7462
7463 ------------------------
7464 -- Resolve_Entry_Call --
7465 ------------------------
7466
7467 procedure Resolve_Entry_Call (N : Node_Id; Typ : Entity_Id) is
7468 Entry_Name : constant Node_Id := Name (N);
7469 Loc : constant Source_Ptr := Sloc (Entry_Name);
7470 Actuals : List_Id;
7471 First_Named : Node_Id;
7472 Nam : Entity_Id;
7473 Norm_OK : Boolean;
7474 Obj : Node_Id;
7475 Was_Over : Boolean;
7476
7477 begin
d81b4bfe
TQ		 7478 -- We kill all checks here, because it does not seem worth the effort to
7479 -- do anything better, an entry call is a big operation.
fbf5a39b
AC		 7480
7481 Kill_All_Checks;
7482
996ae0b0
RK		 7483 -- Processing of the name is similar for entry calls and protected
7484 -- operation calls. Once the entity is determined, we can complete
7485 -- the resolution of the actuals.
7486
7487 -- The selector may be overloaded, in the case of a protected object
7488 -- with overloaded functions. The type of the context is used for
7489 -- resolution.
7490
7491 if Nkind (Entry_Name) = N_Selected_Component
7492 and then Is_Overloaded (Selector_Name (Entry_Name))
7493 and then Typ /= Standard_Void_Type
7494 then
7495 declare
7496 I : Interp_Index;
7497 It : Interp;
7498
7499 begin
7500 Get_First_Interp (Selector_Name (Entry_Name), I, It);
996ae0b0 7501 while Present (It.Typ) loop
996ae0b0
RK		 7502 if Covers (Typ, It.Typ) then
7503 Set_Entity (Selector_Name (Entry_Name), It.Nam);
7504 Set_Etype (Entry_Name, It.Typ);
7505
7506 Generate_Reference (It.Typ, N, ' ');
7507 end if;
7508
7509 Get_Next_Interp (I, It);
7510 end loop;
7511 end;
7512 end if;
7513
7514 Resolve_Entry (Entry_Name);
7515
7516 if Nkind (Entry_Name) = N_Selected_Component then
7517
a77842bd 7518 -- Simple entry call
996ae0b0
RK		 7519
7520 Nam := Entity (Selector_Name (Entry_Name));
7521 Obj := Prefix (Entry_Name);
7522 Was_Over := Is_Overloaded (Selector_Name (Entry_Name));
7523
7524 else pragma Assert (Nkind (Entry_Name) = N_Indexed_Component);
7525
a77842bd 7526 -- Call to member of entry family
996ae0b0
RK		 7527
7528 Nam := Entity (Selector_Name (Prefix (Entry_Name)));
7529 Obj := Prefix (Prefix (Entry_Name));
7530 Was_Over := Is_Overloaded (Selector_Name (Prefix (Entry_Name)));
7531 end if;
7532
5cc9353d
RD		 7533 -- We cannot in general check the maximum depth of protected entry calls
7534 -- at compile time. But we can tell that any protected entry call at all
7535 -- violates a specified nesting depth of zero.
fbf5a39b
AC		 7536
7537 if Is_Protected_Type (Scope (Nam)) then
9f4fd324 7538 Check_Restriction (Max_Entry_Queue_Length, N);
fbf5a39b
AC		 7539 end if;
7540
996ae0b0 7541 -- Use context type to disambiguate a protected function that can be
5cc9353d
RD		 7542 -- called without actuals and that returns an array type, and where the
7543 -- argument list may be an indexing of the returned value.
996ae0b0
RK		 7544
7545 if Ekind (Nam) = E_Function
7546 and then Needs_No_Actuals (Nam)
7547 and then Present (Parameter_Associations (N))
7548 and then
7549 ((Is_Array_Type (Etype (Nam))
7550 and then Covers (Typ, Component_Type (Etype (Nam))))
7551
7552 or else (Is_Access_Type (Etype (Nam))
7553 and then Is_Array_Type (Designated_Type (Etype (Nam)))
19fb051c
AC		 7554 and then
7555 Covers
7556 (Typ,
7557 Component_Type (Designated_Type (Etype (Nam))))))
996ae0b0
RK		 7558 then
7559 declare
7560 Index_Node : Node_Id;
7561
7562 begin
7563 Index_Node :=
7564 Make_Indexed_Component (Loc,
7565 Prefix =>
19fb051c 7566 Make_Function_Call (Loc, Name => Relocate_Node (Entry_Name)),
996ae0b0
RK		 7567 Expressions => Parameter_Associations (N));
7568
5cc9353d
RD		 7569 -- Since we are correcting a node classification error made by the
7570 -- parser, we call Replace rather than Rewrite.
996ae0b0
RK		 7571
7572 Replace (N, Index_Node);
7573 Set_Etype (Prefix (N), Etype (Nam));
7574 Set_Etype (N, Typ);
7575 Resolve_Indexed_Component (N, Typ);
7576 return;
7577 end;
7578 end if;
7579
b7f17b20 7580 if Ekind_In (Nam, E_Entry, E_Entry_Family)
8a0183fd
HK		 7581 and then Present (Contract_Wrapper (Nam))
7582 and then Current_Scope /= Contract_Wrapper (Nam)
b7f17b20 7583 then
87fd6836
AC		 7584
7585 -- Note the entity being called before rewriting the call, so that
7586 -- it appears used at this point.
7587
7588 Generate_Reference (Nam, Entry_Name, 'r');
7589
468ee96a 7590 -- Rewrite as call to the precondition wrapper, adding the task
5cc9353d
RD		 7591 -- object to the list of actuals. If the call is to a member of an
7592 -- entry family, include the index as well.
b7f17b20
ES		 7593
7594 declare
468ee96a 7595 New_Call : Node_Id;
b7f17b20 7596 New_Actuals : List_Id;
19fb051c 7597
b7f17b20
ES		 7598 begin
7599 New_Actuals := New_List (Obj);
3fd9f17c 7600
9fe696a3 7601 if Nkind (Entry_Name) = N_Indexed_Component then
3fd9f17c
AC		 7602 Append_To (New_Actuals,
7603 New_Copy_Tree (First (Expressions (Entry_Name))));
7604 end if;
7605
b7f17b20 7606 Append_List (Parameter_Associations (N), New_Actuals);
468ee96a
AC		 7607 New_Call :=
7608 Make_Procedure_Call_Statement (Loc,
7609 Name =>
8a0183fd 7610 New_Occurrence_Of (Contract_Wrapper (Nam), Loc),
468ee96a 7611 Parameter_Associations => New_Actuals);
b7f17b20 7612 Rewrite (N, New_Call);
ecda544d
ES		 7613
7614 -- Preanalyze and resolve new call. Current procedure is called
7615 -- from Resolve_Call, after which expansion will take place.
7616
7617 Preanalyze_And_Resolve (N);
b7f17b20
ES		 7618 return;
7619 end;
7620 end if;
7621
996ae0b0 7622 -- The operation name may have been overloaded. Order the actuals
5cc9353d
RD		 7623 -- according to the formals of the resolved entity, and set the return
7624 -- type to that of the operation.
996ae0b0
RK		 7625
7626 if Was_Over then
7627 Normalize_Actuals (N, Nam, False, Norm_OK);
7628 pragma Assert (Norm_OK);
fbf5a39b 7629 Set_Etype (N, Etype (Nam));
9d4f9832
AC		 7630
7631 -- Reset the Is_Overloaded flag, since resolution is now completed
7632
be035558
AC		 7633 -- Simple entry call
7634
9d4f9832 7635 if Nkind (Entry_Name) = N_Selected_Component then
9d4f9832
AC		 7636 Set_Is_Overloaded (Selector_Name (Entry_Name), False);
7637
be035558
AC		 7638 -- Call to a member of an entry family
7639
9d4f9832 7640 else pragma Assert (Nkind (Entry_Name) = N_Indexed_Component);
9d4f9832 7641 Set_Is_Overloaded (Selector_Name (Prefix (Entry_Name)), False);
9d4f9832 7642 end if;
996ae0b0
RK		 7643 end if;
7644
7645 Resolve_Actuals (N, Nam);
c92e8586 7646 Check_Internal_Protected_Use (N, Nam);
ae6ede77
AC		 7647
7648 -- Create a call reference to the entry
7649
7650 Generate_Reference (Nam, Entry_Name, 's');
996ae0b0 7651
8a95f4e8 7652 if Ekind_In (Nam, E_Entry, E_Entry_Family) then
996ae0b0
RK		 7653 Check_Potentially_Blocking_Operation (N);
7654 end if;
7655
7656 -- Verify that a procedure call cannot masquerade as an entry
7657 -- call where an entry call is expected.
7658
7659 if Ekind (Nam) = E_Procedure then
996ae0b0
RK		 7660 if Nkind (Parent (N)) = N_Entry_Call_Alternative
7661 and then N = Entry_Call_Statement (Parent (N))
7662 then
7663 Error_Msg_N ("entry call required in select statement", N);
7664
7665 elsif Nkind (Parent (N)) = N_Triggering_Alternative
7666 and then N = Triggering_Statement (Parent (N))
7667 then
7668 Error_Msg_N ("triggering statement cannot be procedure call", N);
7669
7670 elsif Ekind (Scope (Nam)) = E_Task_Type
7671 and then not In_Open_Scopes (Scope (Nam))
7672 then
758c442c 7673 Error_Msg_N ("task has no entry with this name", Entry_Name);
996ae0b0
RK		 7674 end if;
7675 end if;
7676
d81b4bfe
TQ		 7677 -- After resolution, entry calls and protected procedure calls are
7678 -- changed into entry calls, for expansion. The structure of the node
7679 -- does not change, so it can safely be done in place. Protected
7680 -- function calls must keep their structure because they are
7681 -- subexpressions.
996ae0b0
RK		 7682
7683 if Ekind (Nam) /= E_Function then
7684
7685 -- A protected operation that is not a function may modify the
d81b4bfe
TQ		 7686 -- corresponding object, and cannot apply to a constant. If this
7687 -- is an internal call, the prefix is the type itself.
996ae0b0
RK		 7688
7689 if Is_Protected_Type (Scope (Nam))
7690 and then not Is_Variable (Obj)
7691 and then (not Is_Entity_Name (Obj)
7692 or else not Is_Type (Entity (Obj)))
7693 then
7694 Error_Msg_N
7695 ("prefix of protected procedure or entry call must be variable",
7696 Entry_Name);
7697 end if;
7698
7699 Actuals := Parameter_Associations (N);
7700 First_Named := First_Named_Actual (N);
7701
7702 Rewrite (N,
7703 Make_Entry_Call_Statement (Loc,
7704 Name => Entry_Name,
7705 Parameter_Associations => Actuals));
7706
7707 Set_First_Named_Actual (N, First_Named);
7708 Set_Analyzed (N, True);
7709
7710 -- Protected functions can return on the secondary stack, in which
1420b484 7711 -- case we must trigger the transient scope mechanism.
996ae0b0 7712
4460a9bc 7713 elsif Expander_Active
996ae0b0
RK		 7714 and then Requires_Transient_Scope (Etype (Nam))
7715 then
0669bebe 7716 Establish_Transient_Scope (N, Sec_Stack => True);
996ae0b0 7717 end if;
996ae0b0
RK		 7718 end Resolve_Entry_Call;
7719
7720 -------------------------
7721 -- Resolve_Equality_Op --
7722 -------------------------
7723
d81b4bfe
TQ		 7724 -- Both arguments must have the same type, and the boolean context does
7725 -- not participate in the resolution. The first pass verifies that the
7726 -- interpretation is not ambiguous, and the type of the left argument is
7727 -- correctly set, or is Any_Type in case of ambiguity. If both arguments
7728 -- are strings or aggregates, allocators, or Null, they are ambiguous even
7729 -- though they carry a single (universal) type. Diagnose this case here.
996ae0b0
RK		 7730
7731 procedure Resolve_Equality_Op (N : Node_Id; Typ : Entity_Id) is
7732 L : constant Node_Id := Left_Opnd (N);
7733 R : constant Node_Id := Right_Opnd (N);
7734 T : Entity_Id := Find_Unique_Type (L, R);
7735
9b16cb57
RD		 7736 procedure Check_If_Expression (Cond : Node_Id);
7737 -- The resolution rule for if expressions requires that each such must
7738 -- have a unique type. This means that if several dependent expressions
7739 -- are of a non-null anonymous access type, and the context does not
7740 -- impose an expected type (as can be the case in an equality operation)
7741 -- the expression must be rejected.
a8930b80 7742
327b1ba4
AC		 7743 procedure Explain_Redundancy (N : Node_Id);
7744 -- Attempt to explain the nature of a redundant comparison with True. If
7745 -- the expression N is too complex, this routine issues a general error
7746 -- message.
7747
996ae0b0 7748 function Find_Unique_Access_Type return Entity_Id;
289a994b
AC		 7749 -- In the case of allocators and access attributes, the context must
7750 -- provide an indication of the specific access type to be used. If
7751 -- one operand is of such a "generic" access type, check whether there
7752 -- is a specific visible access type that has the same designated type.
7753 -- This is semantically dubious, and of no interest to any real code,
7754 -- but c48008a makes it all worthwhile.
996ae0b0 7755
9b16cb57
RD		 7756 -------------------------
7757 -- Check_If_Expression --
7758 -------------------------
a8930b80 7759
9b16cb57 7760 procedure Check_If_Expression (Cond : Node_Id) is
a8930b80
AC		 7761 Then_Expr : Node_Id;
7762 Else_Expr : Node_Id;
7763
7764 begin
9b16cb57 7765 if Nkind (Cond) = N_If_Expression then
a8930b80
AC		 7766 Then_Expr := Next (First (Expressions (Cond)));
7767 Else_Expr := Next (Then_Expr);
7768
7769 if Nkind (Then_Expr) /= N_Null
7770 and then Nkind (Else_Expr) /= N_Null
7771 then
9b16cb57 7772 Error_Msg_N ("cannot determine type of if expression", Cond);
a8930b80
AC		 7773 end if;
7774 end if;
9b16cb57 7775 end Check_If_Expression;
a8930b80 7776
327b1ba4
AC		 7777 ------------------------
7778 -- Explain_Redundancy --
7779 ------------------------
7780
7781 procedure Explain_Redundancy (N : Node_Id) is
7782 Error : Name_Id;
7783 Val : Node_Id;
7784 Val_Id : Entity_Id;
7785
7786 begin
7787 Val := N;
7788
7789 -- Strip the operand down to an entity
7790
7791 loop
7792 if Nkind (Val) = N_Selected_Component then
7793 Val := Selector_Name (Val);
7794 else
7795 exit;
7796 end if;
7797 end loop;
7798
7799 -- The construct denotes an entity
7800
7801 if Is_Entity_Name (Val) and then Present (Entity (Val)) then
7802 Val_Id := Entity (Val);
7803
7804 -- Do not generate an error message when the comparison is done
7805 -- against the enumeration literal Standard.True.
7806
7807 if Ekind (Val_Id) /= E_Enumeration_Literal then
7808
7809 -- Build a customized error message
7810
7811 Name_Len := 0;
7812 Add_Str_To_Name_Buffer ("?r?");
7813
7814 if Ekind (Val_Id) = E_Component then
7815 Add_Str_To_Name_Buffer ("component ");
7816
7817 elsif Ekind (Val_Id) = E_Constant then
7818 Add_Str_To_Name_Buffer ("constant ");
7819
7820 elsif Ekind (Val_Id) = E_Discriminant then
7821 Add_Str_To_Name_Buffer ("discriminant ");
7822
7823 elsif Is_Formal (Val_Id) then
7824 Add_Str_To_Name_Buffer ("parameter ");
7825
7826 elsif Ekind (Val_Id) = E_Variable then
7827 Add_Str_To_Name_Buffer ("variable ");
7828 end if;
7829
7830 Add_Str_To_Name_Buffer ("& is always True!");
7831 Error := Name_Find;
7832
7833 Error_Msg_NE (Get_Name_String (Error), Val, Val_Id);
7834 end if;
7835
7836 -- The construct is too complex to disect, issue a general message
7837
7838 else
7839 Error_Msg_N ("?r?expression is always True!", Val);
7840 end if;
7841 end Explain_Redundancy;
7842
996ae0b0
RK		 7843 -----------------------------
7844 -- Find_Unique_Access_Type --
7845 -----------------------------
7846
7847 function Find_Unique_Access_Type return Entity_Id is
7848 Acc : Entity_Id;
7849 E : Entity_Id;
1420b484 7850 S : Entity_Id;
996ae0b0
RK		 7851
7852 begin
59fad002
AC		 7853 if Ekind_In (Etype (R), E_Allocator_Type,
7854 E_Access_Attribute_Type)
289a994b 7855 then
996ae0b0 7856 Acc := Designated_Type (Etype (R));
289a994b 7857
59fad002
AC		 7858 elsif Ekind_In (Etype (L), E_Allocator_Type,
7859 E_Access_Attribute_Type)
289a994b 7860 then
996ae0b0 7861 Acc := Designated_Type (Etype (L));
996ae0b0
RK		 7862 else
7863 return Empty;
7864 end if;
7865
1420b484 7866 S := Current_Scope;
996ae0b0
RK		 7867 while S /= Standard_Standard loop
7868 E := First_Entity (S);
996ae0b0 7869 while Present (E) loop
996ae0b0
RK		 7870 if Is_Type (E)
7871 and then Is_Access_Type (E)
7872 and then Ekind (E) /= E_Allocator_Type
7873 and then Designated_Type (E) = Base_Type (Acc)
7874 then
7875 return E;
7876 end if;
7877
7878 Next_Entity (E);
7879 end loop;
7880
7881 S := Scope (S);
7882 end loop;
7883
7884 return Empty;
7885 end Find_Unique_Access_Type;
7886
7887 -- Start of processing for Resolve_Equality_Op
7888
7889 begin
7890 Set_Etype (N, Base_Type (Typ));
7891 Generate_Reference (T, N, ' ');
7892
7893 if T = Any_Fixed then
7894 T := Unique_Fixed_Point_Type (L);
7895 end if;
7896
7897 if T /= Any_Type then
19fb051c
AC		 7898 if T = Any_String or else
7899 T = Any_Composite or else
7900 T = Any_Character
996ae0b0 7901 then
996ae0b0
RK		 7902 if T = Any_Character then
7903 Ambiguous_Character (L);
7904 else
7905 Error_Msg_N ("ambiguous operands for equality", N);
7906 end if;
7907
7908 Set_Etype (N, Any_Type);
7909 return;
7910
7911 elsif T = Any_Access
964f13da 7912 or else Ekind_In (T, E_Allocator_Type, E_Access_Attribute_Type)
996ae0b0
RK		 7913 then
7914 T := Find_Unique_Access_Type;
7915
7916 if No (T) then
7917 Error_Msg_N ("ambiguous operands for equality", N);
7918 Set_Etype (N, Any_Type);
7919 return;
7920 end if;
a8930b80 7921
9b16cb57
RD		 7922 -- If expressions must have a single type, and if the context does
7923 -- not impose one the dependent expressions cannot be anonymous
7924 -- access types.
7925
7926 -- Why no similar processing for case expressions???
a8930b80
AC		 7927
7928 elsif Ada_Version >= Ada_2012
ae2aa109
AC		 7929 and then Ekind_In (Etype (L), E_Anonymous_Access_Type,
7930 E_Anonymous_Access_Subprogram_Type)
7931 and then Ekind_In (Etype (R), E_Anonymous_Access_Type,
7932 E_Anonymous_Access_Subprogram_Type)
a8930b80 7933 then
9b16cb57
RD		 7934 Check_If_Expression (L);
7935 Check_If_Expression (R);
996ae0b0
RK		 7936 end if;
7937
996ae0b0
RK		 7938 Resolve (L, T);
7939 Resolve (R, T);
fbf5a39b 7940
2ba431e5
YM		 7941 -- In SPARK, equality operators = and /= for array types other than
7942 -- String are only defined when, for each index position, the
7943 -- operands have equal static bounds.
b0186f71 7944
975c6896 7945 if Is_Array_Type (T) then
9b16cb57 7946
7b98672f
YM		 7947 -- Protect call to Matching_Static_Array_Bounds to avoid costly
7948 -- operation if not needed.
7949
6480338a 7950 if Restriction_Check_Required (SPARK_05)
7b98672f 7951 and then Base_Type (T) /= Standard_String
975c6896
YM		 7952 and then Base_Type (Etype (L)) = Base_Type (Etype (R))
7953 and then Etype (L) /= Any_Composite -- or else L in error
7954 and then Etype (R) /= Any_Composite -- or else R in error
7955 and then not Matching_Static_Array_Bounds (Etype (L), Etype (R))
7956 then
ce5ba43a 7957 Check_SPARK_05_Restriction
975c6896
YM		 7958 ("array types should have matching static bounds", N);
7959 end if;
b0186f71
AC		 7960 end if;
7961
0669bebe
GB		 7962 -- If the unique type is a class-wide type then it will be expanded
7963 -- into a dispatching call to the predefined primitive. Therefore we
7964 -- check here for potential violation of such restriction.
7965
7966 if Is_Class_Wide_Type (T) then
7967 Check_Restriction (No_Dispatching_Calls, N);
7968 end if;
7969
fbf5a39b
AC		 7970 if Warn_On_Redundant_Constructs
7971 and then Comes_From_Source (N)
327b1ba4 7972 and then Comes_From_Source (R)
fbf5a39b
AC		 7973 and then Is_Entity_Name (R)
7974 and then Entity (R) = Standard_True
fbf5a39b 7975 then
305caf42 7976 Error_Msg_N -- CODEFIX
327b1ba4
AC		 7977 ("?r?comparison with True is redundant!", N);
7978 Explain_Redundancy (Original_Node (R));
fbf5a39b
AC		 7979 end if;
7980
996ae0b0
RK		 7981 Check_Unset_Reference (L);
7982 Check_Unset_Reference (R);
fbf5a39b 7983 Generate_Operator_Reference (N, T);
fad0600d 7984 Check_Low_Bound_Tested (N);
996ae0b0
RK		 7985
7986 -- If this is an inequality, it may be the implicit inequality
7987 -- created for a user-defined operation, in which case the corres-
7988 -- ponding equality operation is not intrinsic, and the operation
7989 -- cannot be constant-folded. Else fold.
7990
7991 if Nkind (N) = N_Op_Eq
7992 or else Comes_From_Source (Entity (N))
7993 or else Ekind (Entity (N)) = E_Operator
7994 or else Is_Intrinsic_Subprogram
19fb051c 7995 (Corresponding_Equality (Entity (N)))
996ae0b0 7996 then
dec6faf1 7997 Analyze_Dimension (N);
996ae0b0 7998 Eval_Relational_Op (N);
45fc7ddb 7999
996ae0b0 8000 elsif Nkind (N) = N_Op_Ne
0669bebe 8001 and then Is_Abstract_Subprogram (Entity (N))
996ae0b0
RK		 8002 then
8003 Error_Msg_NE ("cannot call abstract subprogram &!", N, Entity (N));
8004 end if;
758c442c 8005
d81b4bfe
TQ		 8006 -- Ada 2005: If one operand is an anonymous access type, convert the
8007 -- other operand to it, to ensure that the underlying types match in
8008 -- the back-end. Same for access_to_subprogram, and the conversion
8009 -- verifies that the types are subtype conformant.
b7d1f17f 8010
d81b4bfe
TQ		 8011 -- We apply the same conversion in the case one of the operands is a
8012 -- private subtype of the type of the other.
c8ef728f 8013
b7d1f17f
HK		 8014 -- Why the Expander_Active test here ???
8015
4460a9bc 8016 if Expander_Active
b7d1f17f 8017 and then
964f13da
RD		 8018 (Ekind_In (T, E_Anonymous_Access_Type,
8019 E_Anonymous_Access_Subprogram_Type)
b7d1f17f 8020 or else Is_Private_Type (T))
c8ef728f
ES		 8021 then
8022 if Etype (L) /= T then
8023 Rewrite (L,
8024 Make_Unchecked_Type_Conversion (Sloc (L),
8025 Subtype_Mark => New_Occurrence_Of (T, Sloc (L)),
8026 Expression => Relocate_Node (L)));
8027 Analyze_And_Resolve (L, T);
8028 end if;
8029
8030 if (Etype (R)) /= T then
8031 Rewrite (R,
8032 Make_Unchecked_Type_Conversion (Sloc (R),
8033 Subtype_Mark => New_Occurrence_Of (Etype (L), Sloc (R)),
8034 Expression => Relocate_Node (R)));
8035 Analyze_And_Resolve (R, T);
8036 end if;
8037 end if;
996ae0b0
RK		 8038 end if;
8039 end Resolve_Equality_Op;
8040
8041 ----------------------------------
8042 -- Resolve_Explicit_Dereference --
8043 ----------------------------------
8044
8045 procedure Resolve_Explicit_Dereference (N : Node_Id; Typ : Entity_Id) is
bc5f3720
RD		 8046 Loc : constant Source_Ptr := Sloc (N);
8047 New_N : Node_Id;
8048 P : constant Node_Id := Prefix (N);
50878404
AC		 8049
8050 P_Typ : Entity_Id;
8051 -- The candidate prefix type, if overloaded
8052
bc5f3720
RD		 8053 I : Interp_Index;
8054 It : Interp;
996ae0b0
RK		 8055
8056 begin
c8ef728f 8057 Check_Fully_Declared_Prefix (Typ, P);
50878404 8058 P_Typ := Empty;
996ae0b0 8059
3e586e10
AC		 8060 -- A useful optimization: check whether the dereference denotes an
8061 -- element of a container, and if so rewrite it as a call to the
8062 -- corresponding Element function.
ebb6b0bd 8063
3e586e10
AC		 8064 -- Disabled for now, on advice of ARG. A more restricted form of the
8065 -- predicate might be acceptable ???
8066
8067 -- if Is_Container_Element (N) then
8068 -- return;
8069 -- end if;
8070
996ae0b0
RK		 8071 if Is_Overloaded (P) then
8072
758c442c 8073 -- Use the context type to select the prefix that has the correct
d7a44b14
AC		 8074 -- designated type. Keep the first match, which will be the inner-
8075 -- most.
996ae0b0
RK		 8076
8077 Get_First_Interp (P, I, It);
50878404 8078
996ae0b0 8079 while Present (It.Typ) loop
50878404
AC		 8080 if Is_Access_Type (It.Typ)
8081 and then Covers (Typ, Designated_Type (It.Typ))
8082 then
d7a44b14
AC		 8083 if No (P_Typ) then
8084 P_Typ := It.Typ;
8085 end if;
50878404
AC		 8086
8087 -- Remove access types that do not match, but preserve access
8088 -- to subprogram interpretations, in case a further dereference
8089 -- is needed (see below).
8090
8091 elsif Ekind (It.Typ) /= E_Access_Subprogram_Type then
8092 Remove_Interp (I);
8093 end if;
8094
996ae0b0
RK		 8095 Get_Next_Interp (I, It);
8096 end loop;
8097
50878404
AC		 8098 if Present (P_Typ) then
8099 Resolve (P, P_Typ);
8100 Set_Etype (N, Designated_Type (P_Typ));
8101
bc5f3720 8102 else
758c442c
GD		 8103 -- If no interpretation covers the designated type of the prefix,
8104 -- this is the pathological case where not all implementations of
8105 -- the prefix allow the interpretation of the node as a call. Now
8106 -- that the expected type is known, Remove other interpretations
8107 -- from prefix, rewrite it as a call, and resolve again, so that
8108 -- the proper call node is generated.
bc5f3720
RD		 8109
8110 Get_First_Interp (P, I, It);
8111 while Present (It.Typ) loop
8112 if Ekind (It.Typ) /= E_Access_Subprogram_Type then
8113 Remove_Interp (I);
8114 end if;
8115
8116 Get_Next_Interp (I, It);
8117 end loop;
8118
8119 New_N :=
8120 Make_Function_Call (Loc,
8121 Name =>
8122 Make_Explicit_Dereference (Loc,
8123 Prefix => P),
8124 Parameter_Associations => New_List);
8125
8126 Save_Interps (N, New_N);
8127 Rewrite (N, New_N);
8128 Analyze_And_Resolve (N, Typ);
8129 return;
8130 end if;
8131
29ba9f52 8132 -- If not overloaded, resolve P with its own type
50878404 8133
29ba9f52 8134 else
fbf5a39b 8135 Resolve (P);
996ae0b0
RK		 8136 end if;
8137
72d5c70b
AC		 8138 -- If the prefix might be null, add an access check
8139
8140 if Is_Access_Type (Etype (P))
8141 and then not Can_Never_Be_Null (Etype (P))
8142 then
996ae0b0
RK		 8143 Apply_Access_Check (N);
8144 end if;
8145
758c442c
GD		 8146 -- If the designated type is a packed unconstrained array type, and the
8147 -- explicit dereference is not in the context of an attribute reference,
8148 -- then we must compute and set the actual subtype, since it is needed
8149 -- by Gigi. The reason we exclude the attribute case is that this is
8150 -- handled fine by Gigi, and in fact we use such attributes to build the
8151 -- actual subtype. We also exclude generated code (which builds actual
8152 -- subtypes directly if they are needed).
996ae0b0
RK		 8153
8154 if Is_Array_Type (Etype (N))
8155 and then Is_Packed (Etype (N))
8156 and then not Is_Constrained (Etype (N))
8157 and then Nkind (Parent (N)) /= N_Attribute_Reference
8158 and then Comes_From_Source (N)
8159 then
8160 Set_Etype (N, Get_Actual_Subtype (N));
8161 end if;
8162
d29f68cf 8163 Analyze_Dimension (N);
3373589b 8164
09494c32
AC		 8165 -- Note: No Eval processing is required for an explicit dereference,
8166 -- because such a name can never be static.
996ae0b0
RK		 8167
8168 end Resolve_Explicit_Dereference;
8169
955871d3
AC		 8170 -------------------------------------
8171 -- Resolve_Expression_With_Actions --
8172 -------------------------------------
8173
8174 procedure Resolve_Expression_With_Actions (N : Node_Id; Typ : Entity_Id) is
8175 begin
8176 Set_Etype (N, Typ);
064f4527
TQ		 8177
8178 -- If N has no actions, and its expression has been constant folded,
8179 -- then rewrite N as just its expression. Note, we can't do this in
8180 -- the general case of Is_Empty_List (Actions (N)) as this would cause
8181 -- Expression (N) to be expanded again.
8182
8183 if Is_Empty_List (Actions (N))
8184 and then Compile_Time_Known_Value (Expression (N))
8185 then
8186 Rewrite (N, Expression (N));
8187 end if;
955871d3
AC		 8188 end Resolve_Expression_With_Actions;
8189
5f50020a
ES		 8190 ----------------------------------
8191 -- Resolve_Generalized_Indexing --
8192 ----------------------------------
8193
8194 procedure Resolve_Generalized_Indexing (N : Node_Id; Typ : Entity_Id) is
8195 Indexing : constant Node_Id := Generalized_Indexing (N);
8196 Call : Node_Id;
0566484a 8197 Indexes : List_Id;
5f50020a
ES		 8198 Pref : Node_Id;
8199
8200 begin
0566484a 8201 -- In ASIS mode, propagate the information about the indexes back to
5f50020a
ES		 8202 -- to the original indexing node. The generalized indexing is either
8203 -- a function call, or a dereference of one. The actuals include the
8204 -- prefix of the original node, which is the container expression.
8205
8206 if ASIS_Mode then
8207 Resolve (Indexing, Typ);
8208 Set_Etype (N, Etype (Indexing));
8209 Set_Is_Overloaded (N, False);
32bba3c9 8210
5f50020a 8211 Call := Indexing;
32bba3c9 8212 while Nkind_In (Call, N_Explicit_Dereference, N_Selected_Component)
5f50020a
ES		 8213 loop
8214 Call := Prefix (Call);
8215 end loop;
8216
8217 if Nkind (Call) = N_Function_Call then
66340e0e 8218 Indexes := New_Copy_List (Parameter_Associations (Call));
0566484a
AC		 8219 Pref := Remove_Head (Indexes);
8220 Set_Expressions (N, Indexes);
4039e173
AC		 8221
8222 -- If expression is to be reanalyzed, reset Generalized_Indexing
8223 -- to recreate call node, as is the case when the expression is
8224 -- part of an expression function.
8225
8226 if In_Spec_Expression then
8227 Set_Generalized_Indexing (N, Empty);
8228 end if;
8229
5f50020a
ES		 8230 Set_Prefix (N, Pref);
8231 end if;
8232
8233 else
8234 Rewrite (N, Indexing);
8235 Resolve (N, Typ);
8236 end if;
8237 end Resolve_Generalized_Indexing;
8238
9b16cb57
RD		 8239 ---------------------------
8240 -- Resolve_If_Expression --
8241 ---------------------------
8242
8243 procedure Resolve_If_Expression (N : Node_Id; Typ : Entity_Id) is
8244 Condition : constant Node_Id := First (Expressions (N));
8245 Then_Expr : constant Node_Id := Next (Condition);
8246 Else_Expr : Node_Id := Next (Then_Expr);
8247 Else_Typ : Entity_Id;
8248 Then_Typ : Entity_Id;
8249
8250 begin
8251 Resolve (Condition, Any_Boolean);
8252 Resolve (Then_Expr, Typ);
8253 Then_Typ := Etype (Then_Expr);
8254
30ebb114
AC		 8255 -- When the "then" expression is of a scalar subtype different from the
8256 -- result subtype, then insert a conversion to ensure the generation of
8257 -- a constraint check. The same is done for the else part below, again
8258 -- comparing subtypes rather than base types.
9b16cb57
RD		 8259
8260 if Is_Scalar_Type (Then_Typ)
30ebb114 8261 and then Then_Typ /= Typ
9b16cb57
RD		 8262 then
8263 Rewrite (Then_Expr, Convert_To (Typ, Then_Expr));
8264 Analyze_And_Resolve (Then_Expr, Typ);
8265 end if;
8266
8267 -- If ELSE expression present, just resolve using the determined type
93e90bf4 8268 -- If type is universal, resolve to any member of the class.
9b16cb57
RD		 8269
8270 if Present (Else_Expr) then
93e90bf4
AC		 8271 if Typ = Universal_Integer then
8272 Resolve (Else_Expr, Any_Integer);
8273
8274 elsif Typ = Universal_Real then
8275 Resolve (Else_Expr, Any_Real);
8276
8277 else
8278 Resolve (Else_Expr, Typ);
8279 end if;
8280
9b16cb57
RD		 8281 Else_Typ := Etype (Else_Expr);
8282
b6dd03dd 8283 if Is_Scalar_Type (Else_Typ) and then Else_Typ /= Typ then
9b16cb57
RD		 8284 Rewrite (Else_Expr, Convert_To (Typ, Else_Expr));
8285 Analyze_And_Resolve (Else_Expr, Typ);
b6dd03dd
ES		 8286
8287 -- Apply RM 4.5.7 (17/3): whether the expression is statically or
8288 -- dynamically tagged must be known statically.
8289
8290 elsif Is_Tagged_Type (Typ) and then not Is_Class_Wide_Type (Typ) then
8291 if Is_Dynamically_Tagged (Then_Expr) /=
8292 Is_Dynamically_Tagged (Else_Expr)
8293 then
8294 Error_Msg_N ("all or none of the dependent expressions "
8295 & "can be dynamically tagged", N);
8296 end if;
9b16cb57
RD		 8297 end if;
8298
8299 -- If no ELSE expression is present, root type must be Standard.Boolean
8300 -- and we provide a Standard.True result converted to the appropriate
8301 -- Boolean type (in case it is a derived boolean type).
8302
8303 elsif Root_Type (Typ) = Standard_Boolean then
8304 Else_Expr :=
8305 Convert_To (Typ, New_Occurrence_Of (Standard_True, Sloc (N)));
8306 Analyze_And_Resolve (Else_Expr, Typ);
8307 Append_To (Expressions (N), Else_Expr);
8308
8309 else
8310 Error_Msg_N ("can only omit ELSE expression in Boolean case", N);
8311 Append_To (Expressions (N), Error);
8312 end if;
8313
8314 Set_Etype (N, Typ);
8315 Eval_If_Expression (N);
9b16cb57
RD		 8316 end Resolve_If_Expression;
8317
996ae0b0
RK		 8318 -------------------------------
8319 -- Resolve_Indexed_Component --
8320 -------------------------------
8321
8322 procedure Resolve_Indexed_Component (N : Node_Id; Typ : Entity_Id) is
8323 Name : constant Node_Id := Prefix (N);
8324 Expr : Node_Id;
8325 Array_Type : Entity_Id := Empty; -- to prevent junk warning
8326 Index : Node_Id;
8327
8328 begin
5f50020a
ES		 8329 if Present (Generalized_Indexing (N)) then
8330 Resolve_Generalized_Indexing (N, Typ);
8331 return;
8332 end if;
8333
996ae0b0
RK		 8334 if Is_Overloaded (Name) then
8335
758c442c
GD		 8336 -- Use the context type to select the prefix that yields the correct
8337 -- component type.
996ae0b0
RK		 8338
8339 declare
8340 I : Interp_Index;
8341 It : Interp;
8342 I1 : Interp_Index := 0;
8343 P : constant Node_Id := Prefix (N);
8344 Found : Boolean := False;
8345
8346 begin
8347 Get_First_Interp (P, I, It);
996ae0b0 8348 while Present (It.Typ) loop
996ae0b0
RK		 8349 if (Is_Array_Type (It.Typ)
8350 and then Covers (Typ, Component_Type (It.Typ)))
8351 or else (Is_Access_Type (It.Typ)
8352 and then Is_Array_Type (Designated_Type (It.Typ))
19fb051c
AC		 8353 and then
8354 Covers
8355 (Typ,
8356 Component_Type (Designated_Type (It.Typ))))
996ae0b0
RK		 8357 then
8358 if Found then
8359 It := Disambiguate (P, I1, I, Any_Type);
8360
8361 if It = No_Interp then
8362 Error_Msg_N ("ambiguous prefix for indexing", N);
8363 Set_Etype (N, Typ);
8364 return;
8365
8366 else
8367 Found := True;
8368 Array_Type := It.Typ;
8369 I1 := I;
8370 end if;
8371
8372 else
8373 Found := True;
8374 Array_Type := It.Typ;
8375 I1 := I;
8376 end if;
8377 end if;
8378
8379 Get_Next_Interp (I, It);
8380 end loop;
8381 end;
8382
8383 else
8384 Array_Type := Etype (Name);
8385 end if;
8386
8387 Resolve (Name, Array_Type);
8388 Array_Type := Get_Actual_Subtype_If_Available (Name);
8389
8390 -- If prefix is access type, dereference to get real array type.
8391 -- Note: we do not apply an access check because the expander always
8392 -- introduces an explicit dereference, and the check will happen there.
8393
8394 if Is_Access_Type (Array_Type) then
8395 Array_Type := Designated_Type (Array_Type);
8396 end if;
8397
a77842bd 8398 -- If name was overloaded, set component type correctly now
f3d57416 8399 -- If a misplaced call to an entry family (which has no index types)
b7d1f17f 8400 -- return. Error will be diagnosed from calling context.
996ae0b0 8401
b7d1f17f
HK		 8402 if Is_Array_Type (Array_Type) then
8403 Set_Etype (N, Component_Type (Array_Type));
8404 else
8405 return;
8406 end if;
996ae0b0
RK		 8407
8408 Index := First_Index (Array_Type);
8409 Expr := First (Expressions (N));
8410
758c442c
GD		 8411 -- The prefix may have resolved to a string literal, in which case its
8412 -- etype has a special representation. This is only possible currently
8413 -- if the prefix is a static concatenation, written in functional
8414 -- notation.
996ae0b0
RK		 8415
8416 if Ekind (Array_Type) = E_String_Literal_Subtype then
8417 Resolve (Expr, Standard_Positive);
8418
8419 else
8420 while Present (Index) and Present (Expr) loop
8421 Resolve (Expr, Etype (Index));
8422 Check_Unset_Reference (Expr);
8423
8424 if Is_Scalar_Type (Etype (Expr)) then
8425 Apply_Scalar_Range_Check (Expr, Etype (Index));
8426 else
8427 Apply_Range_Check (Expr, Get_Actual_Subtype (Index));
8428 end if;
8429
8430 Next_Index (Index);
8431 Next (Expr);
8432 end loop;
8433 end if;
8434
dec6faf1
AC		 8435 Analyze_Dimension (N);
8436
0669bebe
GB		 8437 -- Do not generate the warning on suspicious index if we are analyzing
8438 -- package Ada.Tags; otherwise we will report the warning with the
8439 -- Prims_Ptr field of the dispatch table.
8440
8441 if Scope (Etype (Prefix (N))) = Standard_Standard
8442 or else not
8443 Is_RTU (Cunit_Entity (Get_Source_Unit (Etype (Prefix (N)))),
8444 Ada_Tags)
8445 then
8446 Warn_On_Suspicious_Index (Name, First (Expressions (N)));
8447 Eval_Indexed_Component (N);
8448 end if;
c28408b7 8449
c2a2dbcc
RD		 8450 -- If the array type is atomic, and the component is not atomic, then
8451 -- this is worth a warning, since we have a situation where the access
8452 -- to the component may cause extra read/writes of the atomic array
8453 -- object, or partial word accesses, which could be unexpected.
c28408b7
RD		 8454
8455 if Nkind (N) = N_Indexed_Component
c2a2dbcc
RD		 8456 and then Is_Atomic_Ref_With_Address (N)
8457 and then not (Has_Atomic_Components (Array_Type)
8458 or else (Is_Entity_Name (Prefix (N))
8459 and then Has_Atomic_Components
8460 (Entity (Prefix (N)))))
8461 and then not Is_Atomic (Component_Type (Array_Type))
c28408b7 8462 then
b6dd03dd
ES		 8463 Error_Msg_N
8464 ("??access to non-atomic component of atomic array", Prefix (N));
8465 Error_Msg_N
8466 ("??\may cause unexpected accesses to atomic object", Prefix (N));
c28408b7 8467 end if;
996ae0b0
RK		 8468 end Resolve_Indexed_Component;
8469
8470 -----------------------------
8471 -- Resolve_Integer_Literal --
8472 -----------------------------
8473
8474 procedure Resolve_Integer_Literal (N : Node_Id; Typ : Entity_Id) is
8475 begin
8476 Set_Etype (N, Typ);
8477 Eval_Integer_Literal (N);
8478 end Resolve_Integer_Literal;
8479
15ce9ca2
AC		 8480 --------------------------------
8481 -- Resolve_Intrinsic_Operator --
8482 --------------------------------
996ae0b0
RK		 8483
8484 procedure Resolve_Intrinsic_Operator (N : Node_Id; Typ : Entity_Id) is
7a5b62b0
AC		 8485 Btyp : constant Entity_Id := Base_Type (Underlying_Type (Typ));
8486 Op : Entity_Id;
8487 Arg1 : Node_Id;
8488 Arg2 : Node_Id;
996ae0b0 8489
78efd712
AC		 8490 function Convert_Operand (Opnd : Node_Id) return Node_Id;
8491 -- If the operand is a literal, it cannot be the expression in a
8492 -- conversion. Use a qualified expression instead.
8493
b6dd03dd
ES		 8494 ---------------------
8495 -- Convert_Operand --
8496 ---------------------
8497
78efd712
AC		 8498 function Convert_Operand (Opnd : Node_Id) return Node_Id is
8499 Loc : constant Source_Ptr := Sloc (Opnd);
8500 Res : Node_Id;
b6dd03dd 8501
78efd712
AC		 8502 begin
8503 if Nkind_In (Opnd, N_Integer_Literal, N_Real_Literal) then
8504 Res :=
8505 Make_Qualified_Expression (Loc,
8506 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
8507 Expression => Relocate_Node (Opnd));
8508 Analyze (Res);
8509
8510 else
8511 Res := Unchecked_Convert_To (Btyp, Opnd);
8512 end if;
8513
8514 return Res;
8515 end Convert_Operand;
8516
d72e7628 8517 -- Start of processing for Resolve_Intrinsic_Operator
7109f4f5 8518
996ae0b0 8519 begin
305caf42
AC		 8520 -- We must preserve the original entity in a generic setting, so that
8521 -- the legality of the operation can be verified in an instance.
8522
4460a9bc 8523 if not Expander_Active then
305caf42
AC		 8524 return;
8525 end if;
8526
996ae0b0 8527 Op := Entity (N);
996ae0b0
RK		 8528 while Scope (Op) /= Standard_Standard loop
8529 Op := Homonym (Op);
8530 pragma Assert (Present (Op));
8531 end loop;
8532
8533 Set_Entity (N, Op);
af152989 8534 Set_Is_Overloaded (N, False);
996ae0b0 8535
7109f4f5
AC		 8536 -- If the result or operand types are private, rewrite with unchecked
8537 -- conversions on the operands and the result, to expose the proper
8538 -- underlying numeric type.
996ae0b0 8539
7109f4f5
AC		 8540 if Is_Private_Type (Typ)
8541 or else Is_Private_Type (Etype (Left_Opnd (N)))
8542 or else Is_Private_Type (Etype (Right_Opnd (N)))
8543 then
78efd712 8544 Arg1 := Convert_Operand (Left_Opnd (N));
fbf5a39b
AC		 8545
8546 if Nkind (N) = N_Op_Expon then
8547 Arg2 := Unchecked_Convert_To (Standard_Integer, Right_Opnd (N));
8548 else
78efd712 8549 Arg2 := Convert_Operand (Right_Opnd (N));
fbf5a39b
AC		 8550 end if;
8551
bb481772
AC		 8552 if Nkind (Arg1) = N_Type_Conversion then
8553 Save_Interps (Left_Opnd (N), Expression (Arg1));
8554 end if;
8555
8556 if Nkind (Arg2) = N_Type_Conversion then
8557 Save_Interps (Right_Opnd (N), Expression (Arg2));
8558 end if;
996ae0b0 8559
fbf5a39b
AC		 8560 Set_Left_Opnd (N, Arg1);
8561 Set_Right_Opnd (N, Arg2);
8562
8563 Set_Etype (N, Btyp);
8564 Rewrite (N, Unchecked_Convert_To (Typ, N));
8565 Resolve (N, Typ);
8566
8567 elsif Typ /= Etype (Left_Opnd (N))
8568 or else Typ /= Etype (Right_Opnd (N))
8569 then
d81b4bfe 8570 -- Add explicit conversion where needed, and save interpretations in
7a5b62b0 8571 -- case operands are overloaded.
fbf5a39b 8572
af152989 8573 Arg1 := Convert_To (Typ, Left_Opnd (N));
fbf5a39b
AC		 8574 Arg2 := Convert_To (Typ, Right_Opnd (N));
8575
8576 if Nkind (Arg1) = N_Type_Conversion then
8577 Save_Interps (Left_Opnd (N), Expression (Arg1));
af152989
AC		 8578 else
8579 Save_Interps (Left_Opnd (N), Arg1);
fbf5a39b
AC		 8580 end if;
8581
8582 if Nkind (Arg2) = N_Type_Conversion then
8583 Save_Interps (Right_Opnd (N), Expression (Arg2));
af152989 8584 else
0ab80019 8585 Save_Interps (Right_Opnd (N), Arg2);
fbf5a39b
AC		 8586 end if;
8587
8588 Rewrite (Left_Opnd (N), Arg1);
8589 Rewrite (Right_Opnd (N), Arg2);
8590 Analyze (Arg1);
8591 Analyze (Arg2);
8592 Resolve_Arithmetic_Op (N, Typ);
8593
8594 else
8595 Resolve_Arithmetic_Op (N, Typ);
8596 end if;
996ae0b0
RK		 8597 end Resolve_Intrinsic_Operator;
8598
fbf5a39b
AC		 8599 --------------------------------------
8600 -- Resolve_Intrinsic_Unary_Operator --
8601 --------------------------------------
8602
8603 procedure Resolve_Intrinsic_Unary_Operator
8604 (N : Node_Id;
8605 Typ : Entity_Id)
8606 is
8607 Btyp : constant Entity_Id := Base_Type (Underlying_Type (Typ));
8608 Op : Entity_Id;
8609 Arg2 : Node_Id;
8610
8611 begin
8612 Op := Entity (N);
fbf5a39b
AC		 8613 while Scope (Op) /= Standard_Standard loop
8614 Op := Homonym (Op);
8615 pragma Assert (Present (Op));
8616 end loop;
8617
8618 Set_Entity (N, Op);
8619
8620 if Is_Private_Type (Typ) then
8621 Arg2 := Unchecked_Convert_To (Btyp, Right_Opnd (N));
8622 Save_Interps (Right_Opnd (N), Expression (Arg2));
8623
8624 Set_Right_Opnd (N, Arg2);
8625
8626 Set_Etype (N, Btyp);
8627 Rewrite (N, Unchecked_Convert_To (Typ, N));
8628 Resolve (N, Typ);
8629
8630 else
8631 Resolve_Unary_Op (N, Typ);
8632 end if;
8633 end Resolve_Intrinsic_Unary_Operator;
8634
996ae0b0
RK		 8635 ------------------------
8636 -- Resolve_Logical_Op --
8637 ------------------------
8638
8639 procedure Resolve_Logical_Op (N : Node_Id; Typ : Entity_Id) is
8640 B_Typ : Entity_Id;
8641
8642 begin
f61580d4
AC		 8643 Check_No_Direct_Boolean_Operators (N);
8644
758c442c
GD		 8645 -- Predefined operations on scalar types yield the base type. On the
8646 -- other hand, logical operations on arrays yield the type of the
8647 -- arguments (and the context).
996ae0b0
RK		 8648
8649 if Is_Array_Type (Typ) then
8650 B_Typ := Typ;
8651 else
8652 B_Typ := Base_Type (Typ);
8653 end if;
8654
8655 -- The following test is required because the operands of the operation
8656 -- may be literals, in which case the resulting type appears to be
8657 -- compatible with a signed integer type, when in fact it is compatible
8658 -- only with modular types. If the context itself is universal, the
8659 -- operation is illegal.
8660
7a5b62b0 8661 if not Valid_Boolean_Arg (Typ) then
996ae0b0
RK		 8662 Error_Msg_N ("invalid context for logical operation", N);
8663 Set_Etype (N, Any_Type);
8664 return;
8665
8666 elsif Typ = Any_Modular then
8667 Error_Msg_N
8668 ("no modular type available in this context", N);
8669 Set_Etype (N, Any_Type);
8670 return;
19fb051c 8671
07fc65c4
GB		 8672 elsif Is_Modular_Integer_Type (Typ)
8673 and then Etype (Left_Opnd (N)) = Universal_Integer
8674 and then Etype (Right_Opnd (N)) = Universal_Integer
8675 then
8676 Check_For_Visible_Operator (N, B_Typ);
996ae0b0
RK		 8677 end if;
8678
f2d10a02
AC		 8679 -- Replace AND by AND THEN, or OR by OR ELSE, if Short_Circuit_And_Or
8680 -- is active and the result type is standard Boolean (do not mess with
8681 -- ops that return a nonstandard Boolean type, because something strange
8682 -- is going on).
8683
8684 -- Note: you might expect this replacement to be done during expansion,
8685 -- but that doesn't work, because when the pragma Short_Circuit_And_Or
8686 -- is used, no part of the right operand of an "and" or "or" operator
8687 -- should be executed if the left operand would short-circuit the
8688 -- evaluation of the corresponding "and then" or "or else". If we left
8689 -- the replacement to expansion time, then run-time checks associated
8690 -- with such operands would be evaluated unconditionally, due to being
af89615f 8691 -- before the condition prior to the rewriting as short-circuit forms
f2d10a02
AC		 8692 -- during expansion.
8693
8694 if Short_Circuit_And_Or
8695 and then B_Typ = Standard_Boolean
8696 and then Nkind_In (N, N_Op_And, N_Op_Or)
8697 then
0566484a
AC		 8698 -- Mark the corresponding putative SCO operator as truly a logical
8699 -- (and short-circuit) operator.
8700
8701 if Generate_SCO and then Comes_From_Source (N) then
8702 Set_SCO_Logical_Operator (N);
8703 end if;
8704
f2d10a02
AC		 8705 if Nkind (N) = N_Op_And then
8706 Rewrite (N,
8707 Make_And_Then (Sloc (N),
8708 Left_Opnd => Relocate_Node (Left_Opnd (N)),
8709 Right_Opnd => Relocate_Node (Right_Opnd (N))));
8710 Analyze_And_Resolve (N, B_Typ);
8711
8712 -- Case of OR changed to OR ELSE
8713
8714 else
8715 Rewrite (N,
8716 Make_Or_Else (Sloc (N),
8717 Left_Opnd => Relocate_Node (Left_Opnd (N)),
8718 Right_Opnd => Relocate_Node (Right_Opnd (N))));
8719 Analyze_And_Resolve (N, B_Typ);
8720 end if;
8721
8722 -- Return now, since analysis of the rewritten ops will take care of
8723 -- other reference bookkeeping and expression folding.
8724
8725 return;
8726 end if;
8727
996ae0b0
RK		 8728 Resolve (Left_Opnd (N), B_Typ);
8729 Resolve (Right_Opnd (N), B_Typ);
8730
8731 Check_Unset_Reference (Left_Opnd (N));
8732 Check_Unset_Reference (Right_Opnd (N));
8733
8734 Set_Etype (N, B_Typ);
fbf5a39b 8735 Generate_Operator_Reference (N, B_Typ);
996ae0b0 8736 Eval_Logical_Op (N);
9f90d123 8737
2ba431e5
YM		 8738 -- In SPARK, logical operations AND, OR and XOR for arrays are defined
8739 -- only when both operands have same static lower and higher bounds. Of
8740 -- course the types have to match, so only check if operands are
8741 -- compatible and the node itself has no errors.
9f90d123 8742
f5afb270
AC		 8743 if Is_Array_Type (B_Typ)
8744 and then Nkind (N) in N_Binary_Op
8745 then
8746 declare
8747 Left_Typ : constant Node_Id := Etype (Left_Opnd (N));
8748 Right_Typ : constant Node_Id := Etype (Right_Opnd (N));
2598ee6d 8749
f5afb270 8750 begin
7b98672f
YM		 8751 -- Protect call to Matching_Static_Array_Bounds to avoid costly
8752 -- operation if not needed.
8753
6480338a 8754 if Restriction_Check_Required (SPARK_05)
7b98672f 8755 and then Base_Type (Left_Typ) = Base_Type (Right_Typ)
f5afb270
AC		 8756 and then Left_Typ /= Any_Composite -- or Left_Opnd in error
8757 and then Right_Typ /= Any_Composite -- or Right_Opnd in error
8758 and then not Matching_Static_Array_Bounds (Left_Typ, Right_Typ)
8759 then
ce5ba43a 8760 Check_SPARK_05_Restriction
f5afb270
AC		 8761 ("array types should have matching static bounds", N);
8762 end if;
8763 end;
8764 end if;
996ae0b0
RK		 8765 end Resolve_Logical_Op;
8766
8767 ---------------------------
8768 -- Resolve_Membership_Op --
8769 ---------------------------
8770
5cc9353d
RD		 8771 -- The context can only be a boolean type, and does not determine the
8772 -- arguments. Arguments should be unambiguous, but the preference rule for
8773 -- universal types applies.
996ae0b0
RK		 8774
8775 procedure Resolve_Membership_Op (N : Node_Id; Typ : Entity_Id) is
07fc65c4
GB		 8776 pragma Warnings (Off, Typ);
8777
197e4514 8778 L : constant Node_Id := Left_Opnd (N);
b1c11e0e 8779 R : constant Node_Id := Right_Opnd (N);
996ae0b0
RK		 8780 T : Entity_Id;
8781
197e4514 8782 procedure Resolve_Set_Membership;
5cc9353d
RD		 8783 -- Analysis has determined a unique type for the left operand. Use it to
8784 -- resolve the disjuncts.
197e4514
AC		 8785
8786 ----------------------------
8787 -- Resolve_Set_Membership --
8788 ----------------------------
8789
8790 procedure Resolve_Set_Membership is
9cb62ce3 8791 Alt : Node_Id;
cd1a470a 8792 Ltyp : Entity_Id;
197e4514
AC		 8793
8794 begin
cd1a470a
AC		 8795 -- If the left operand is overloaded, find type compatible with not
8796 -- overloaded alternative of the right operand.
8797
8798 if Is_Overloaded (L) then
8799 Ltyp := Empty;
8800 Alt := First (Alternatives (N));
8801 while Present (Alt) loop
8802 if not Is_Overloaded (Alt) then
8803 Ltyp := Intersect_Types (L, Alt);
8804 exit;
8805 else
8806 Next (Alt);
8807 end if;
8808 end loop;
8809
8810 -- Unclear how to resolve expression if all alternatives are also
8811 -- overloaded.
8812
8813 if No (Ltyp) then
8814 Error_Msg_N ("ambiguous expression", N);
8815 end if;
8816
8817 else
8818 Ltyp := Etype (L);
8819 end if;
8820
9cb62ce3 8821 Resolve (L, Ltyp);
197e4514
AC		 8822
8823 Alt := First (Alternatives (N));
8824 while Present (Alt) loop
8825
8826 -- Alternative is an expression, a range
8827 -- or a subtype mark.
8828
8829 if not Is_Entity_Name (Alt)
8830 or else not Is_Type (Entity (Alt))
8831 then
9cb62ce3 8832 Resolve (Alt, Ltyp);
197e4514
AC		 8833 end if;
8834
8835 Next (Alt);
8836 end loop;
9cb62ce3
AC		 8837
8838 -- Check for duplicates for discrete case
8839
8840 if Is_Discrete_Type (Ltyp) then
8841 declare
8842 type Ent is record
8843 Alt : Node_Id;
8844 Val : Uint;
8845 end record;
8846
8847 Alts : array (0 .. List_Length (Alternatives (N))) of Ent;
8848 Nalts : Nat;
8849
8850 begin
8851 -- Loop checking duplicates. This is quadratic, but giant sets
8852 -- are unlikely in this context so it's a reasonable choice.
8853
8854 Nalts := 0;
8855 Alt := First (Alternatives (N));
8856 while Present (Alt) loop
edab6088 8857 if Is_OK_Static_Expression (Alt)
9cb62ce3 8858 and then (Nkind_In (Alt, N_Integer_Literal,
324ac540 8859 N_Character_Literal)
9cb62ce3
AC		 8860 or else Nkind (Alt) in N_Has_Entity)
8861 then
8862 Nalts := Nalts + 1;
8863 Alts (Nalts) := (Alt, Expr_Value (Alt));
8864
8865 for J in 1 .. Nalts - 1 loop
8866 if Alts (J).Val = Alts (Nalts).Val then
8867 Error_Msg_Sloc := Sloc (Alts (J).Alt);
324ac540 8868 Error_Msg_N ("duplicate of value given#??", Alt);
9cb62ce3
AC		 8869 end if;
8870 end loop;
8871 end if;
8872
8873 Alt := Next (Alt);
8874 end loop;
8875 end;
8876 end if;
197e4514
AC		 8877 end Resolve_Set_Membership;
8878
442c0581 8879 -- Start of processing for Resolve_Membership_Op
197e4514 8880
996ae0b0
RK		 8881 begin
8882 if L = Error or else R = Error then
8883 return;
8884 end if;
8885
197e4514
AC		 8886 if Present (Alternatives (N)) then
8887 Resolve_Set_Membership;
edab6088 8888 goto SM_Exit;
197e4514
AC		 8889
8890 elsif not Is_Overloaded (R)
996ae0b0 8891 and then
19fb051c
AC		 8892 (Etype (R) = Universal_Integer
8893 or else
996ae0b0
RK		 8894 Etype (R) = Universal_Real)
8895 and then Is_Overloaded (L)
8896 then
8897 T := Etype (R);
1420b484 8898
d81b4bfe 8899 -- Ada 2005 (AI-251): Support the following case:
1420b484
JM		 8900
8901 -- type I is interface;
8902 -- type T is tagged ...
8903
c8ef728f 8904 -- function Test (O : I'Class) is
1420b484
JM		 8905 -- begin
8906 -- return O in T'Class.
8907 -- end Test;
8908
d81b4bfe 8909 -- In this case we have nothing else to do. The membership test will be
e7c0dd39 8910 -- done at run time.
1420b484 8911
0791fbe9 8912 elsif Ada_Version >= Ada_2005
1420b484
JM		 8913 and then Is_Class_Wide_Type (Etype (L))
8914 and then Is_Interface (Etype (L))
8915 and then Is_Class_Wide_Type (Etype (R))
8916 and then not Is_Interface (Etype (R))
8917 then
8918 return;
996ae0b0
RK		 8919 else
8920 T := Intersect_Types (L, R);
8921 end if;
8922
9a0ddeee
AC		 8923 -- If mixed-mode operations are present and operands are all literal,
8924 -- the only interpretation involves Duration, which is probably not
8925 -- the intention of the programmer.
8926
8927 if T = Any_Fixed then
8928 T := Unique_Fixed_Point_Type (N);
8929
8930 if T = Any_Type then
8931 return;
8932 end if;
8933 end if;
8934
996ae0b0
RK		 8935 Resolve (L, T);
8936 Check_Unset_Reference (L);
8937
8938 if Nkind (R) = N_Range
8939 and then not Is_Scalar_Type (T)
8940 then
8941 Error_Msg_N ("scalar type required for range", R);
8942 end if;
8943
8944 if Is_Entity_Name (R) then
8945 Freeze_Expression (R);
8946 else
8947 Resolve (R, T);
8948 Check_Unset_Reference (R);
8949 end if;
8950
edab6088
RD		 8951 -- Here after resolving membership operation
8952
8953 <<SM_Exit>>
8954
996ae0b0
RK		 8955 Eval_Membership_Op (N);
8956 end Resolve_Membership_Op;
8957
8958 ------------------
8959 -- Resolve_Null --
8960 ------------------
8961
8962 procedure Resolve_Null (N : Node_Id; Typ : Entity_Id) is
b1c11e0e
JM		 8963 Loc : constant Source_Ptr := Sloc (N);
8964
996ae0b0 8965 begin
758c442c 8966 -- Handle restriction against anonymous null access values This
6ba6b1e3 8967 -- restriction can be turned off using -gnatdj.
996ae0b0 8968
0ab80019 8969 -- Ada 2005 (AI-231): Remove restriction
2820d220 8970
0791fbe9 8971 if Ada_Version < Ada_2005
2820d220 8972 and then not Debug_Flag_J
996ae0b0
RK		 8973 and then Ekind (Typ) = E_Anonymous_Access_Type
8974 and then Comes_From_Source (N)
8975 then
d81b4bfe
TQ		 8976 -- In the common case of a call which uses an explicitly null value
8977 -- for an access parameter, give specialized error message.
996ae0b0 8978
d3b00ce3 8979 if Nkind (Parent (N)) in N_Subprogram_Call then
996ae0b0
RK		 8980 Error_Msg_N
8981 ("null is not allowed as argument for an access parameter", N);
8982
8983 -- Standard message for all other cases (are there any?)
8984
8985 else
8986 Error_Msg_N
8987 ("null cannot be of an anonymous access type", N);
8988 end if;
8989 end if;
8990
b1c11e0e
JM		 8991 -- Ada 2005 (AI-231): Generate the null-excluding check in case of
8992 -- assignment to a null-excluding object
8993
0791fbe9 8994 if Ada_Version >= Ada_2005
b1c11e0e
JM		 8995 and then Can_Never_Be_Null (Typ)
8996 and then Nkind (Parent (N)) = N_Assignment_Statement
8997 then
8998 if not Inside_Init_Proc then
8999 Insert_Action
9000 (Compile_Time_Constraint_Error (N,
324ac540 9001 "(Ada 2005) null not allowed in null-excluding objects??"),
b1c11e0e
JM		 9002 Make_Raise_Constraint_Error (Loc,
9003 Reason => CE_Access_Check_Failed));
9004 else
9005 Insert_Action (N,
9006 Make_Raise_Constraint_Error (Loc,
9007 Reason => CE_Access_Check_Failed));
9008 end if;
9009 end if;
9010
d81b4bfe
TQ		 9011 -- In a distributed context, null for a remote access to subprogram may
9012 -- need to be replaced with a special record aggregate. In this case,
9013 -- return after having done the transformation.
996ae0b0
RK		 9014
9015 if (Ekind (Typ) = E_Record_Type
9016 or else Is_Remote_Access_To_Subprogram_Type (Typ))
9017 and then Remote_AST_Null_Value (N, Typ)
9018 then
9019 return;
9020 end if;
9021
a77842bd 9022 -- The null literal takes its type from the context
996ae0b0
RK		 9023
9024 Set_Etype (N, Typ);
9025 end Resolve_Null;
9026
9027 -----------------------
9028 -- Resolve_Op_Concat --
9029 -----------------------
9030
9031 procedure Resolve_Op_Concat (N : Node_Id; Typ : Entity_Id) is
996ae0b0 9032
10303118
BD		 9033 -- We wish to avoid deep recursion, because concatenations are often
9034 -- deeply nested, as in A&B&...&Z. Therefore, we walk down the left
9035 -- operands nonrecursively until we find something that is not a simple
9036 -- concatenation (A in this case). We resolve that, and then walk back
9037 -- up the tree following Parent pointers, calling Resolve_Op_Concat_Rest
9038 -- to do the rest of the work at each level. The Parent pointers allow
9039 -- us to avoid recursion, and thus avoid running out of memory. See also
d81b4bfe 9040 -- Sem_Ch4.Analyze_Concatenation, where a similar approach is used.
996ae0b0 9041
10303118
BD		 9042 NN : Node_Id := N;
9043 Op1 : Node_Id;
996ae0b0 9044
10303118
BD		 9045 begin
9046 -- The following code is equivalent to:
996ae0b0 9047
10303118
BD		 9048 -- Resolve_Op_Concat_First (NN, Typ);
9049 -- Resolve_Op_Concat_Arg (N, ...);
9050 -- Resolve_Op_Concat_Rest (N, Typ);
996ae0b0 9051
10303118
BD		 9052 -- where the Resolve_Op_Concat_Arg call recurses back here if the left
9053 -- operand is a concatenation.
996ae0b0 9054
10303118 9055 -- Walk down left operands
996ae0b0 9056
10303118
BD		 9057 loop
9058 Resolve_Op_Concat_First (NN, Typ);
9059 Op1 := Left_Opnd (NN);
9060 exit when not (Nkind (Op1) = N_Op_Concat
9061 and then not Is_Array_Type (Component_Type (Typ))
9062 and then Entity (Op1) = Entity (NN));
9063 NN := Op1;
9064 end loop;
996ae0b0 9065
10303118 9066 -- Now (given the above example) NN is A&B and Op1 is A
996ae0b0 9067
10303118 9068 -- First resolve Op1 ...
9ebe3743 9069
10303118 9070 Resolve_Op_Concat_Arg (NN, Op1, Typ, Is_Component_Left_Opnd (NN));
9ebe3743 9071
10303118
BD		 9072 -- ... then walk NN back up until we reach N (where we started), calling
9073 -- Resolve_Op_Concat_Rest along the way.
9ebe3743 9074
10303118
BD		 9075 loop
9076 Resolve_Op_Concat_Rest (NN, Typ);
9077 exit when NN = N;
9078 NN := Parent (NN);
9079 end loop;
2933b16c 9080
fe5d3068 9081 if Base_Type (Etype (N)) /= Standard_String then
ce5ba43a 9082 Check_SPARK_05_Restriction
fe5d3068 9083 ("result of concatenation should have type String", N);
2933b16c 9084 end if;
10303118 9085 end Resolve_Op_Concat;
9ebe3743 9086
10303118
BD		 9087 ---------------------------
9088 -- Resolve_Op_Concat_Arg --
9089 ---------------------------
996ae0b0 9090
10303118
BD		 9091 procedure Resolve_Op_Concat_Arg
9092 (N : Node_Id;
9093 Arg : Node_Id;
9094 Typ : Entity_Id;
9095 Is_Comp : Boolean)
9096 is
9097 Btyp : constant Entity_Id := Base_Type (Typ);
668a19bc 9098 Ctyp : constant Entity_Id := Component_Type (Typ);
996ae0b0 9099
10303118
BD		 9100 begin
9101 if In_Instance then
9102 if Is_Comp
9103 or else (not Is_Overloaded (Arg)
9104 and then Etype (Arg) /= Any_Composite
668a19bc 9105 and then Covers (Ctyp, Etype (Arg)))
10303118 9106 then
668a19bc 9107 Resolve (Arg, Ctyp);
10303118
BD		 9108 else
9109 Resolve (Arg, Btyp);
9110 end if;
fbf5a39b 9111
668a19bc
ES		 9112 -- If both Array & Array and Array & Component are visible, there is a
9113 -- potential ambiguity that must be reported.
9114
9115 elsif Has_Compatible_Type (Arg, Ctyp) then
10303118 9116 if Nkind (Arg) = N_Aggregate
668a19bc 9117 and then Is_Composite_Type (Ctyp)
10303118 9118 then
668a19bc 9119 if Is_Private_Type (Ctyp) then
10303118 9120 Resolve (Arg, Btyp);
668a19bc
ES		 9121
9122 -- If the operation is user-defined and not overloaded use its
9123 -- profile. The operation may be a renaming, in which case it has
9124 -- been rewritten, and we want the original profile.
9125
9126 elsif not Is_Overloaded (N)
9127 and then Comes_From_Source (Entity (Original_Node (N)))
9128 and then Ekind (Entity (Original_Node (N))) = E_Function
9129 then
9130 Resolve (Arg,
9131 Etype
9132 (Next_Formal (First_Formal (Entity (Original_Node (N))))));
9133 return;
9134
9135 -- Otherwise an aggregate may match both the array type and the
9136 -- component type.
9137
10303118
BD		 9138 else
9139 Error_Msg_N ("ambiguous aggregate must be qualified", Arg);
9140 Set_Etype (Arg, Any_Type);
996ae0b0
RK		 9141 end if;
9142
9143 else
10303118
BD		 9144 if Is_Overloaded (Arg)
9145 and then Has_Compatible_Type (Arg, Typ)
9146 and then Etype (Arg) /= Any_Type
9147 then
9148 declare
9149 I : Interp_Index;
9150 It : Interp;
9151 Func : Entity_Id;
9152
9153 begin
9154 Get_First_Interp (Arg, I, It);
9155 Func := It.Nam;
9156 Get_Next_Interp (I, It);
9157
9158 -- Special-case the error message when the overloading is
9159 -- caused by a function that yields an array and can be
9160 -- called without parameters.
9161
9162 if It.Nam = Func then
9163 Error_Msg_Sloc := Sloc (Func);
9164 Error_Msg_N ("ambiguous call to function#", Arg);
9165 Error_Msg_NE
9166 ("\\interpretation as call yields&", Arg, Typ);
9167 Error_Msg_NE
9168 ("\\interpretation as indexing of call yields&",
9169 Arg, Component_Type (Typ));
9170
9171 else
668a19bc 9172 Error_Msg_N ("ambiguous operand for concatenation!", Arg);
19fb051c 9173
10303118
BD		 9174 Get_First_Interp (Arg, I, It);
9175 while Present (It.Nam) loop
9176 Error_Msg_Sloc := Sloc (It.Nam);
9177
668a19bc
ES		 9178 if Base_Type (It.Typ) = Btyp
9179 or else
9180 Base_Type (It.Typ) = Base_Type (Ctyp)
10303118 9181 then
4e7a4f6e
AC		 9182 Error_Msg_N -- CODEFIX
9183 ("\\possible interpretation#", Arg);
10303118
BD		 9184 end if;
9185
9186 Get_Next_Interp (I, It);
9187 end loop;
9188 end if;
9189 end;
9190 end if;
9191
9192 Resolve (Arg, Component_Type (Typ));
9193
9194 if Nkind (Arg) = N_String_Literal then
9195 Set_Etype (Arg, Component_Type (Typ));
9196 end if;
9197
9198 if Arg = Left_Opnd (N) then
9199 Set_Is_Component_Left_Opnd (N);
9200 else
9201 Set_Is_Component_Right_Opnd (N);
9202 end if;
996ae0b0
RK		 9203 end if;
9204
10303118
BD		 9205 else
9206 Resolve (Arg, Btyp);
9207 end if;
9208
2ba431e5 9209 -- Concatenation is restricted in SPARK: each operand must be either a
92e77027
AC		 9210 -- string literal, the name of a string constant, a static character or
9211 -- string expression, or another concatenation. Arg cannot be a
9212 -- concatenation here as callers of Resolve_Op_Concat_Arg call it
9213 -- separately on each final operand, past concatenation operations.
2933b16c 9214
fe5d3068 9215 if Is_Character_Type (Etype (Arg)) then
edab6088 9216 if not Is_OK_Static_Expression (Arg) then
ce5ba43a 9217 Check_SPARK_05_Restriction
5b5588dd 9218 ("character operand for concatenation should be static", Arg);
fe5d3068 9219 end if;
2933b16c 9220
fe5d3068 9221 elsif Is_String_Type (Etype (Arg)) then
92e77027
AC		 9222 if not (Nkind_In (Arg, N_Identifier, N_Expanded_Name)
9223 and then Is_Constant_Object (Entity (Arg)))
edab6088 9224 and then not Is_OK_Static_Expression (Arg)
92e77027 9225 then
ce5ba43a 9226 Check_SPARK_05_Restriction
5b5588dd 9227 ("string operand for concatenation should be static", Arg);
fe5d3068 9228 end if;
2933b16c 9229
b9e48541
AC		 9230 -- Do not issue error on an operand that is neither a character nor a
9231 -- string, as the error is issued in Resolve_Op_Concat.
2933b16c 9232
fe5d3068
YM		 9233 else
9234 null;
2933b16c
RD		 9235 end if;
9236
10303118
BD		 9237 Check_Unset_Reference (Arg);
9238 end Resolve_Op_Concat_Arg;
996ae0b0 9239
10303118
BD		 9240 -----------------------------
9241 -- Resolve_Op_Concat_First --
9242 -----------------------------
9243
9244 procedure Resolve_Op_Concat_First (N : Node_Id; Typ : Entity_Id) is
9245 Btyp : constant Entity_Id := Base_Type (Typ);
9246 Op1 : constant Node_Id := Left_Opnd (N);
9247 Op2 : constant Node_Id := Right_Opnd (N);
996ae0b0
RK		 9248
9249 begin
dae2b8ea
HK		 9250 -- The parser folds an enormous sequence of concatenations of string
9251 -- literals into "" & "...", where the Is_Folded_In_Parser flag is set
4fc26524 9252 -- in the right operand. If the expression resolves to a predefined "&"
dae2b8ea
HK		 9253 -- operator, all is well. Otherwise, the parser's folding is wrong, so
9254 -- we give an error. See P_Simple_Expression in Par.Ch4.
9255
9256 if Nkind (Op2) = N_String_Literal
9257 and then Is_Folded_In_Parser (Op2)
9258 and then Ekind (Entity (N)) = E_Function
9259 then
9260 pragma Assert (Nkind (Op1) = N_String_Literal -- should be ""
9261 and then String_Length (Strval (Op1)) = 0);
9262 Error_Msg_N ("too many user-defined concatenations", N);
9263 return;
9264 end if;
9265
996ae0b0
RK		 9266 Set_Etype (N, Btyp);
9267
9268 if Is_Limited_Composite (Btyp) then
9269 Error_Msg_N ("concatenation not available for limited array", N);
fbf5a39b 9270 Explain_Limited_Type (Btyp, N);
996ae0b0 9271 end if;
10303118 9272 end Resolve_Op_Concat_First;
996ae0b0 9273
10303118
BD		 9274 ----------------------------
9275 -- Resolve_Op_Concat_Rest --
9276 ----------------------------
996ae0b0 9277
10303118
BD		 9278 procedure Resolve_Op_Concat_Rest (N : Node_Id; Typ : Entity_Id) is
9279 Op1 : constant Node_Id := Left_Opnd (N);
9280 Op2 : constant Node_Id := Right_Opnd (N);
996ae0b0 9281
10303118
BD		 9282 begin
9283 Resolve_Op_Concat_Arg (N, Op2, Typ, Is_Component_Right_Opnd (N));
996ae0b0 9284
fbf5a39b 9285 Generate_Operator_Reference (N, Typ);
996ae0b0
RK		 9286
9287 if Is_String_Type (Typ) then
9288 Eval_Concatenation (N);
9289 end if;
9290
d81b4bfe
TQ		 9291 -- If this is not a static concatenation, but the result is a string
9292 -- type (and not an array of strings) ensure that static string operands
9293 -- have their subtypes properly constructed.
996ae0b0
RK		 9294
9295 if Nkind (N) /= N_String_Literal
9296 and then Is_Character_Type (Component_Type (Typ))
9297 then
9298 Set_String_Literal_Subtype (Op1, Typ);
9299 Set_String_Literal_Subtype (Op2, Typ);
9300 end if;
10303118 9301 end Resolve_Op_Concat_Rest;
996ae0b0
RK		 9302
9303 ----------------------
9304 -- Resolve_Op_Expon --
9305 ----------------------
9306
9307 procedure Resolve_Op_Expon (N : Node_Id; Typ : Entity_Id) is
9308 B_Typ : constant Entity_Id := Base_Type (Typ);
9309
9310 begin
f3d57416 9311 -- Catch attempts to do fixed-point exponentiation with universal
758c442c 9312 -- operands, which is a case where the illegality is not caught during
4530b919
AC		 9313 -- normal operator analysis. This is not done in preanalysis mode
9314 -- since the tree is not fully decorated during preanalysis.
996ae0b0 9315
4530b919
AC		 9316 if Full_Analysis then
9317 if Is_Fixed_Point_Type (Typ) and then Comes_From_Source (N) then
9318 Error_Msg_N ("exponentiation not available for fixed point", N);
9319 return;
4d792549 9320
4530b919
AC		 9321 elsif Nkind (Parent (N)) in N_Op
9322 and then Is_Fixed_Point_Type (Etype (Parent (N)))
9323 and then Etype (N) = Universal_Real
9324 and then Comes_From_Source (N)
9325 then
9326 Error_Msg_N ("exponentiation not available for fixed point", N);
9327 return;
9328 end if;
996ae0b0
RK		 9329 end if;
9330
fbf5a39b
AC		 9331 if Comes_From_Source (N)
9332 and then Ekind (Entity (N)) = E_Function
9333 and then Is_Imported (Entity (N))
9334 and then Is_Intrinsic_Subprogram (Entity (N))
9335 then
9336 Resolve_Intrinsic_Operator (N, Typ);
9337 return;
9338 end if;
9339
996ae0b0
RK		 9340 if Etype (Left_Opnd (N)) = Universal_Integer
9341 or else Etype (Left_Opnd (N)) = Universal_Real
9342 then
9343 Check_For_Visible_Operator (N, B_Typ);
9344 end if;
9345
9346 -- We do the resolution using the base type, because intermediate values
4530b919 9347 -- in expressions are always of the base type, not a subtype of it.
996ae0b0
RK		 9348
9349 Resolve (Left_Opnd (N), B_Typ);
9350 Resolve (Right_Opnd (N), Standard_Integer);
9351
7dbd3de9
RD		 9352 -- For integer types, right argument must be in Natural range
9353
9354 if Is_Integer_Type (Typ) then
9355 Apply_Scalar_Range_Check (Right_Opnd (N), Standard_Natural);
9356 end if;
9357
996ae0b0
RK		 9358 Check_Unset_Reference (Left_Opnd (N));
9359 Check_Unset_Reference (Right_Opnd (N));
9360
9361 Set_Etype (N, B_Typ);
fbf5a39b 9362 Generate_Operator_Reference (N, B_Typ);
dec6faf1
AC		 9363
9364 Analyze_Dimension (N);
9365
15954beb 9366 if Ada_Version >= Ada_2012 and then Has_Dimension_System (B_Typ) then
6c57023b 9367 -- Evaluate the exponentiation operator for dimensioned type
dec6faf1 9368
6c57023b
AC		 9369 Eval_Op_Expon_For_Dimensioned_Type (N, B_Typ);
9370 else
9371 Eval_Op_Expon (N);
dec6faf1
AC		 9372 end if;
9373
996ae0b0
RK		 9374 -- Set overflow checking bit. Much cleverer code needed here eventually
9375 -- and perhaps the Resolve routines should be separated for the various
9376 -- arithmetic operations, since they will need different processing. ???
9377
9378 if Nkind (N) in N_Op then
9379 if not Overflow_Checks_Suppressed (Etype (N)) then
fbf5a39b 9380 Enable_Overflow_Check (N);
996ae0b0
RK		 9381 end if;
9382 end if;
996ae0b0
RK		 9383 end Resolve_Op_Expon;
9384
9385 --------------------
9386 -- Resolve_Op_Not --
9387 --------------------
9388
9389 procedure Resolve_Op_Not (N : Node_Id; Typ : Entity_Id) is
9390 B_Typ : Entity_Id;
9391
9392 function Parent_Is_Boolean return Boolean;
5cc9353d
RD		 9393 -- This function determines if the parent node is a boolean operator or
9394 -- operation (comparison op, membership test, or short circuit form) and
9395 -- the not in question is the left operand of this operation. Note that
9396 -- if the not is in parens, then false is returned.
996ae0b0 9397
aa180613
RD		 9398 -----------------------
9399 -- Parent_Is_Boolean --
9400 -----------------------
9401
996ae0b0
RK		 9402 function Parent_Is_Boolean return Boolean is
9403 begin
9404 if Paren_Count (N) /= 0 then
9405 return False;
9406
9407 else
9408 case Nkind (Parent (N)) is
d8f43ee6
HK		 9409 when N_And_Then
9410 | N_In
9411 | N_Not_In
9412 | N_Op_And
9413 | N_Op_Eq
9414 | N_Op_Ge
9415 | N_Op_Gt
9416 | N_Op_Le
9417 | N_Op_Lt
9418 | N_Op_Ne
9419 | N_Op_Or
9420 | N_Op_Xor
9421 | N_Or_Else
9422 =>
996ae0b0
RK		 9423 return Left_Opnd (Parent (N)) = N;
9424
9425 when others =>
9426 return False;
9427 end case;
9428 end if;
9429 end Parent_Is_Boolean;
9430
9431 -- Start of processing for Resolve_Op_Not
9432
9433 begin
758c442c
GD		 9434 -- Predefined operations on scalar types yield the base type. On the
9435 -- other hand, logical operations on arrays yield the type of the
9436 -- arguments (and the context).
996ae0b0
RK		 9437
9438 if Is_Array_Type (Typ) then
9439 B_Typ := Typ;
9440 else
9441 B_Typ := Base_Type (Typ);
9442 end if;
9443
f3d57416 9444 -- Straightforward case of incorrect arguments
aa180613 9445
7a5b62b0 9446 if not Valid_Boolean_Arg (Typ) then
996ae0b0
RK		 9447 Error_Msg_N ("invalid operand type for operator&", N);
9448 Set_Etype (N, Any_Type);
9449 return;
9450
aa180613
RD		 9451 -- Special case of probable missing parens
9452
fbf5a39b 9453 elsif Typ = Universal_Integer or else Typ = Any_Modular then
996ae0b0 9454 if Parent_Is_Boolean then
ed2233dc 9455 Error_Msg_N
996ae0b0
RK		 9456 ("operand of not must be enclosed in parentheses",
9457 Right_Opnd (N));
9458 else
9459 Error_Msg_N
9460 ("no modular type available in this context", N);
9461 end if;
9462
9463 Set_Etype (N, Any_Type);
9464 return;
9465
5cc9353d 9466 -- OK resolution of NOT
aa180613 9467
996ae0b0 9468 else
aa180613
RD		 9469 -- Warn if non-boolean types involved. This is a case like not a < b
9470 -- where a and b are modular, where we will get (not a) < b and most
9471 -- likely not (a < b) was intended.
9472
9473 if Warn_On_Questionable_Missing_Parens
9474 and then not Is_Boolean_Type (Typ)
996ae0b0
RK		 9475 and then Parent_Is_Boolean
9476 then
324ac540 9477 Error_Msg_N ("?q?not expression should be parenthesized here!", N);
996ae0b0
RK		 9478 end if;
9479
09bc9ab6
RD		 9480 -- Warn on double negation if checking redundant constructs
9481
9482 if Warn_On_Redundant_Constructs
9483 and then Comes_From_Source (N)
9484 and then Comes_From_Source (Right_Opnd (N))
9485 and then Root_Type (Typ) = Standard_Boolean
9486 and then Nkind (Right_Opnd (N)) = N_Op_Not
9487 then
324ac540 9488 Error_Msg_N ("redundant double negation?r?", N);
09bc9ab6
RD		 9489 end if;
9490
9491 -- Complete resolution and evaluation of NOT
9492
996ae0b0
RK		 9493 Resolve (Right_Opnd (N), B_Typ);
9494 Check_Unset_Reference (Right_Opnd (N));
9495 Set_Etype (N, B_Typ);
fbf5a39b 9496 Generate_Operator_Reference (N, B_Typ);
996ae0b0
RK		 9497 Eval_Op_Not (N);
9498 end if;
9499 end Resolve_Op_Not;
9500
9501 -----------------------------
9502 -- Resolve_Operator_Symbol --
9503 -----------------------------
9504
9505 -- Nothing to be done, all resolved already
9506
9507 procedure Resolve_Operator_Symbol (N : Node_Id; Typ : Entity_Id) is
07fc65c4
GB		 9508 pragma Warnings (Off, N);
9509 pragma Warnings (Off, Typ);
9510
996ae0b0
RK		 9511 begin
9512 null;
9513 end Resolve_Operator_Symbol;
9514
9515 ----------------------------------
9516 -- Resolve_Qualified_Expression --
9517 ----------------------------------
9518
9519 procedure Resolve_Qualified_Expression (N : Node_Id; Typ : Entity_Id) is
07fc65c4
GB		 9520 pragma Warnings (Off, Typ);
9521
996ae0b0
RK		 9522 Target_Typ : constant Entity_Id := Entity (Subtype_Mark (N));
9523 Expr : constant Node_Id := Expression (N);
9524
9525 begin
9526 Resolve (Expr, Target_Typ);
9527
7b98672f
YM		 9528 -- Protect call to Matching_Static_Array_Bounds to avoid costly
9529 -- operation if not needed.
9530
6480338a 9531 if Restriction_Check_Required (SPARK_05)
7b98672f 9532 and then Is_Array_Type (Target_Typ)
b0186f71 9533 and then Is_Array_Type (Etype (Expr))
db72f10a 9534 and then Etype (Expr) /= Any_Composite -- or else Expr in error
b0186f71
AC		 9535 and then not Matching_Static_Array_Bounds (Target_Typ, Etype (Expr))
9536 then
ce5ba43a 9537 Check_SPARK_05_Restriction
fe5d3068 9538 ("array types should have matching static bounds", N);
b0186f71
AC		 9539 end if;
9540
5cc9353d
RD		 9541 -- A qualified expression requires an exact match of the type, class-
9542 -- wide matching is not allowed. However, if the qualifying type is
9543 -- specific and the expression has a class-wide type, it may still be
9544 -- okay, since it can be the result of the expansion of a call to a
9545 -- dispatching function, so we also have to check class-wideness of the
9546 -- type of the expression's original node.
1420b484
JM		 9547
9548 if (Is_Class_Wide_Type (Target_Typ)
9549 or else
9550 (Is_Class_Wide_Type (Etype (Expr))
9551 and then Is_Class_Wide_Type (Etype (Original_Node (Expr)))))
996ae0b0
RK		 9552 and then Base_Type (Etype (Expr)) /= Base_Type (Target_Typ)
9553 then
9554 Wrong_Type (Expr, Target_Typ);
9555 end if;
9556
90c63b09
AC		 9557 -- If the target type is unconstrained, then we reset the type of the
9558 -- result from the type of the expression. For other cases, the actual
9559 -- subtype of the expression is the target type.
996ae0b0
RK		 9560
9561 if Is_Composite_Type (Target_Typ)
9562 and then not Is_Constrained (Target_Typ)
9563 then
9564 Set_Etype (N, Etype (Expr));
9565 end if;
9566
dec6faf1 9567 Analyze_Dimension (N);
996ae0b0 9568 Eval_Qualified_Expression (N);
6cf7eae6
AC		 9569
9570 -- If we still have a qualified expression after the static evaluation,
9571 -- then apply a scalar range check if needed. The reason that we do this
9572 -- after the Eval call is that otherwise, the application of the range
9573 -- check may convert an illegal static expression and result in warning
9574 -- rather than giving an error (e.g Integer'(Integer'Last + 1)).
9575
9576 if Nkind (N) = N_Qualified_Expression and then Is_Scalar_Type (Typ) then
9577 Apply_Scalar_Range_Check (Expr, Typ);
9578 end if;
1e60643a 9579
558fbeb0
HK		 9580 -- Finally, check whether a predicate applies to the target type. This
9581 -- comes from AI12-0100. As for type conversions, check the enclosing
9582 -- context to prevent an infinite expansion.
1e60643a
AC		 9583
9584 if Has_Predicates (Target_Typ) then
9585 if Nkind (Parent (N)) = N_Function_Call
9586 and then Present (Name (Parent (N)))
9587 and then (Is_Predicate_Function (Entity (Name (Parent (N))))
9588 or else
9589 Is_Predicate_Function_M (Entity (Name (Parent (N)))))
9590 then
9591 null;
9592
0026dd0a
AC		 9593 -- In the case of a qualified expression in an allocator, the check
9594 -- is applied when expanding the allocator, so avoid redundant check.
9595
9596 elsif Nkind (N) = N_Qualified_Expression
9597 and then Nkind (Parent (N)) /= N_Allocator
9598 then
1e60643a
AC		 9599 Apply_Predicate_Check (N, Target_Typ);
9600 end if;
9601 end if;
996ae0b0
RK		 9602 end Resolve_Qualified_Expression;
9603
7610fee8
AC		 9604 ------------------------------
9605 -- Resolve_Raise_Expression --
9606 ------------------------------
9607
9608 procedure Resolve_Raise_Expression (N : Node_Id; Typ : Entity_Id) is
9609 begin
3e586e10
AC		 9610 if Typ = Raise_Type then
9611 Error_Msg_N ("cannot find unique type for raise expression", N);
9612 Set_Etype (N, Any_Type);
9613 else
9614 Set_Etype (N, Typ);
9615 end if;
7610fee8
AC		 9616 end Resolve_Raise_Expression;
9617
996ae0b0
RK		 9618 -------------------
9619 -- Resolve_Range --
9620 -------------------
9621
9622 procedure Resolve_Range (N : Node_Id; Typ : Entity_Id) is
9623 L : constant Node_Id := Low_Bound (N);
9624 H : constant Node_Id := High_Bound (N);
9625
bd29d519
AC		 9626 function First_Last_Ref return Boolean;
9627 -- Returns True if N is of the form X'First .. X'Last where X is the
9628 -- same entity for both attributes.
9629
9630 --------------------
9631 -- First_Last_Ref --
9632 --------------------
9633
9634 function First_Last_Ref return Boolean is
9635 Lorig : constant Node_Id := Original_Node (L);
9636 Horig : constant Node_Id := Original_Node (H);
9637
9638 begin
9639 if Nkind (Lorig) = N_Attribute_Reference
9640 and then Nkind (Horig) = N_Attribute_Reference
9641 and then Attribute_Name (Lorig) = Name_First
9642 and then Attribute_Name (Horig) = Name_Last
9643 then
9644 declare
9645 PL : constant Node_Id := Prefix (Lorig);
9646 PH : constant Node_Id := Prefix (Horig);
9647 begin
9648 if Is_Entity_Name (PL)
9649 and then Is_Entity_Name (PH)
9650 and then Entity (PL) = Entity (PH)
9651 then
9652 return True;
9653 end if;
9654 end;
9655 end if;
9656
9657 return False;
9658 end First_Last_Ref;
9659
9660 -- Start of processing for Resolve_Range
9661
996ae0b0
RK		 9662 begin
9663 Set_Etype (N, Typ);
6d67bea9
AC		 9664
9665 -- The lower bound should be in Typ. The higher bound can be in Typ's
9666 -- base type if the range is null. It may still be invalid if it is
9667 -- higher than the lower bound. This is checked later in the context in
9668 -- which the range appears.
9669
996ae0b0 9670 Resolve (L, Typ);
6d67bea9 9671 Resolve (H, Base_Type (Typ));
996ae0b0 9672
bd29d519
AC		 9673 -- Check for inappropriate range on unordered enumeration type
9674
9675 if Bad_Unordered_Enumeration_Reference (N, Typ)
9676
9677 -- Exclude X'First .. X'Last if X is the same entity for both
9678
9679 and then not First_Last_Ref
9680 then
b1d12996
AC		 9681 Error_Msg_Sloc := Sloc (Typ);
9682 Error_Msg_NE
9683 ("subrange of unordered enumeration type& declared#?U?", N, Typ);
498d1b80
AC		 9684 end if;
9685
996ae0b0
RK		 9686 Check_Unset_Reference (L);
9687 Check_Unset_Reference (H);
9688
9689 -- We have to check the bounds for being within the base range as
758c442c
GD		 9690 -- required for a non-static context. Normally this is automatic and
9691 -- done as part of evaluating expressions, but the N_Range node is an
9692 -- exception, since in GNAT we consider this node to be a subexpression,
9693 -- even though in Ada it is not. The circuit in Sem_Eval could check for
9694 -- this, but that would put the test on the main evaluation path for
9695 -- expressions.
996ae0b0
RK		 9696
9697 Check_Non_Static_Context (L);
9698 Check_Non_Static_Context (H);
9699
b7d1f17f
HK		 9700 -- Check for an ambiguous range over character literals. This will
9701 -- happen with a membership test involving only literals.
9702
9703 if Typ = Any_Character then
9704 Ambiguous_Character (L);
9705 Set_Etype (N, Any_Type);
9706 return;
9707 end if;
9708
5cc9353d
RD		 9709 -- If bounds are static, constant-fold them, so size computations are
9710 -- identical between front-end and back-end. Do not perform this
fbf5a39b 9711 -- transformation while analyzing generic units, as type information
5cc9353d 9712 -- would be lost when reanalyzing the constant node in the instance.
fbf5a39b 9713
4460a9bc 9714 if Is_Discrete_Type (Typ) and then Expander_Active then
fbf5a39b 9715 if Is_OK_Static_Expression (L) then
edab6088 9716 Fold_Uint (L, Expr_Value (L), Is_OK_Static_Expression (L));
fbf5a39b
AC		 9717 end if;
9718
9719 if Is_OK_Static_Expression (H) then
edab6088 9720 Fold_Uint (H, Expr_Value (H), Is_OK_Static_Expression (H));
fbf5a39b
AC		 9721 end if;
9722 end if;
996ae0b0
RK		 9723 end Resolve_Range;
9724
9725 --------------------------
9726 -- Resolve_Real_Literal --
9727 --------------------------
9728
9729 procedure Resolve_Real_Literal (N : Node_Id; Typ : Entity_Id) is
9730 Actual_Typ : constant Entity_Id := Etype (N);
9731
9732 begin
9733 -- Special processing for fixed-point literals to make sure that the
5cc9353d
RD		 9734 -- value is an exact multiple of small where this is required. We skip
9735 -- this for the universal real case, and also for generic types.
996ae0b0
RK		 9736
9737 if Is_Fixed_Point_Type (Typ)
9738 and then Typ /= Universal_Fixed
9739 and then Typ /= Any_Fixed
9740 and then not Is_Generic_Type (Typ)
9741 then
9742 declare
9743 Val : constant Ureal := Realval (N);
9744 Cintr : constant Ureal := Val / Small_Value (Typ);
9745 Cint : constant Uint := UR_Trunc (Cintr);
9746 Den : constant Uint := Norm_Den (Cintr);
9747 Stat : Boolean;
9748
9749 begin
9750 -- Case of literal is not an exact multiple of the Small
9751
9752 if Den /= 1 then
9753
5cc9353d
RD		 9754 -- For a source program literal for a decimal fixed-point type,
9755 -- this is statically illegal (RM 4.9(36)).
996ae0b0
RK		 9756
9757 if Is_Decimal_Fixed_Point_Type (Typ)
9758 and then Actual_Typ = Universal_Real
9759 and then Comes_From_Source (N)
9760 then
9761 Error_Msg_N ("value has extraneous low order digits", N);
9762 end if;
9763
bc5f3720
RD		 9764 -- Generate a warning if literal from source
9765
edab6088 9766 if Is_OK_Static_Expression (N)
bc5f3720
RD		 9767 and then Warn_On_Bad_Fixed_Value
9768 then
9769 Error_Msg_N
324ac540 9770 ("?b?static fixed-point value is not a multiple of Small!",
bc5f3720
RD		 9771 N);
9772 end if;
9773
996ae0b0
RK		 9774 -- Replace literal by a value that is the exact representation
9775 -- of a value of the type, i.e. a multiple of the small value,
9776 -- by truncation, since Machine_Rounds is false for all GNAT
9777 -- fixed-point types (RM 4.9(38)).
9778
edab6088 9779 Stat := Is_OK_Static_Expression (N);
996ae0b0
RK		 9780 Rewrite (N,
9781 Make_Real_Literal (Sloc (N),
9782 Realval => Small_Value (Typ) * Cint));
9783
9784 Set_Is_Static_Expression (N, Stat);
9785 end if;
9786
9787 -- In all cases, set the corresponding integer field
9788
9789 Set_Corresponding_Integer_Value (N, Cint);
9790 end;
9791 end if;
9792
9793 -- Now replace the actual type by the expected type as usual
9794
9795 Set_Etype (N, Typ);
9796 Eval_Real_Literal (N);
9797 end Resolve_Real_Literal;
9798
9799 -----------------------
9800 -- Resolve_Reference --
9801 -----------------------
9802
9803 procedure Resolve_Reference (N : Node_Id; Typ : Entity_Id) is
9804 P : constant Node_Id := Prefix (N);
9805
9806 begin
9807 -- Replace general access with specific type
9808
9809 if Ekind (Etype (N)) = E_Allocator_Type then
9810 Set_Etype (N, Base_Type (Typ));
9811 end if;
9812
9813 Resolve (P, Designated_Type (Etype (N)));
9814
5cc9353d
RD		 9815 -- If we are taking the reference of a volatile entity, then treat it as
9816 -- a potential modification of this entity. This is too conservative,
9817 -- but necessary because remove side effects can cause transformations
9818 -- of normal assignments into reference sequences that otherwise fail to
9819 -- notice the modification.
996ae0b0 9820
fbf5a39b 9821 if Is_Entity_Name (P) and then Treat_As_Volatile (Entity (P)) then
45fc7ddb 9822 Note_Possible_Modification (P, Sure => False);
996ae0b0
RK		 9823 end if;
9824 end Resolve_Reference;
9825
9826 --------------------------------
9827 -- Resolve_Selected_Component --
9828 --------------------------------
9829
9830 procedure Resolve_Selected_Component (N : Node_Id; Typ : Entity_Id) is
9831 Comp : Entity_Id;
9832 Comp1 : Entity_Id := Empty; -- prevent junk warning
c2a2dbcc 9833 P : constant Node_Id := Prefix (N);
996ae0b0
RK		 9834 S : constant Node_Id := Selector_Name (N);
9835 T : Entity_Id := Etype (P);
9836 I : Interp_Index;
9837 I1 : Interp_Index := 0; -- prevent junk warning
9838 It : Interp;
9839 It1 : Interp;
9840 Found : Boolean;
9841
6510f4c9
GB		 9842 function Init_Component return Boolean;
9843 -- Check whether this is the initialization of a component within an
fbf5a39b 9844 -- init proc (by assignment or call to another init proc). If true,
6510f4c9
GB		 9845 -- there is no need for a discriminant check.
9846
9847 --------------------
9848 -- Init_Component --
9849 --------------------
9850
9851 function Init_Component return Boolean is
9852 begin
9853 return Inside_Init_Proc
9854 and then Nkind (Prefix (N)) = N_Identifier
9855 and then Chars (Prefix (N)) = Name_uInit
9856 and then Nkind (Parent (Parent (N))) = N_Case_Statement_Alternative;
9857 end Init_Component;
9858
9859 -- Start of processing for Resolve_Selected_Component
9860
996ae0b0
RK		 9861 begin
9862 if Is_Overloaded (P) then
9863
9864 -- Use the context type to select the prefix that has a selector
9865 -- of the correct name and type.
9866
9867 Found := False;
9868 Get_First_Interp (P, I, It);
9869
9870 Search : while Present (It.Typ) loop
9871 if Is_Access_Type (It.Typ) then
9872 T := Designated_Type (It.Typ);
9873 else
9874 T := It.Typ;
9875 end if;
9876
95eb8b69
AC		 9877 -- Locate selected component. For a private prefix the selector
9878 -- can denote a discriminant.
9879
9880 if Is_Record_Type (T) or else Is_Private_Type (T) then
36fcf362
RD		 9881
9882 -- The visible components of a class-wide type are those of
9883 -- the root type.
9884
9885 if Is_Class_Wide_Type (T) then
9886 T := Etype (T);
9887 end if;
9888
996ae0b0 9889 Comp := First_Entity (T);
996ae0b0 9890 while Present (Comp) loop
996ae0b0 9891 if Chars (Comp) = Chars (S)
dda38714 9892 and then Covers (Typ, Etype (Comp))
996ae0b0
RK		 9893 then
9894 if not Found then
9895 Found := True;
9896 I1 := I;
9897 It1 := It;
9898 Comp1 := Comp;
9899
9900 else
9901 It := Disambiguate (P, I1, I, Any_Type);
9902
9903 if It = No_Interp then
9904 Error_Msg_N
9905 ("ambiguous prefix for selected component", N);
9906 Set_Etype (N, Typ);
9907 return;
9908
9909 else
9910 It1 := It;
9911
c8ef728f
ES		 9912 -- There may be an implicit dereference. Retrieve
9913 -- designated record type.
9914
9915 if Is_Access_Type (It1.Typ) then
9916 T := Designated_Type (It1.Typ);
9917 else
9918 T := It1.Typ;
9919 end if;
9920
9921 if Scope (Comp1) /= T then
996ae0b0
RK		 9922
9923 -- Resolution chooses the new interpretation.
9924 -- Find the component with the right name.
9925
c8ef728f 9926 Comp1 := First_Entity (T);
996ae0b0
RK		 9927 while Present (Comp1)
9928 and then Chars (Comp1) /= Chars (S)
9929 loop
9930 Comp1 := Next_Entity (Comp1);
9931 end loop;
9932 end if;
9933
9934 exit Search;
9935 end if;
9936 end if;
9937 end if;
9938
9939 Comp := Next_Entity (Comp);
9940 end loop;
996ae0b0
RK		 9941 end if;
9942
9943 Get_Next_Interp (I, It);
996ae0b0
RK		 9944 end loop Search;
9945
9926efec 9946 -- There must be a legal interpretation at this point
dda38714
AC		 9947
9948 pragma Assert (Found);
996ae0b0
RK		 9949 Resolve (P, It1.Typ);
9950 Set_Etype (N, Typ);
e7ba564f 9951 Set_Entity_With_Checks (S, Comp1);
996ae0b0
RK		 9952
9953 else
fbf5a39b 9954 -- Resolve prefix with its type
996ae0b0
RK		 9955
9956 Resolve (P, T);
9957 end if;
9958
aa180613
RD		 9959 -- Generate cross-reference. We needed to wait until full overloading
9960 -- resolution was complete to do this, since otherwise we can't tell if
01e17342 9961 -- we are an lvalue or not.
aa180613
RD		 9962
9963 if May_Be_Lvalue (N) then
9964 Generate_Reference (Entity (S), S, 'm');
9965 else
9966 Generate_Reference (Entity (S), S, 'r');
9967 end if;
9968
c8ef728f
ES		 9969 -- If prefix is an access type, the node will be transformed into an
9970 -- explicit dereference during expansion. The type of the node is the
9971 -- designated type of that of the prefix.
996ae0b0
RK		 9972
9973 if Is_Access_Type (Etype (P)) then
996ae0b0 9974 T := Designated_Type (Etype (P));
c8ef728f 9975 Check_Fully_Declared_Prefix (T, P);
996ae0b0
RK		 9976 else
9977 T := Etype (P);
9978 end if;
9979
c386239f
AC		 9980 -- Set flag for expander if discriminant check required on a component
9981 -- appearing within a variant.
ef1c0511 9982
996ae0b0 9983 if Has_Discriminants (T)
1b1d88b1 9984 and then Ekind (Entity (S)) = E_Component
996ae0b0
RK		 9985 and then Present (Original_Record_Component (Entity (S)))
9986 and then Ekind (Original_Record_Component (Entity (S))) = E_Component
c96c518f
AC		 9987 and then
9988 Is_Declared_Within_Variant (Original_Record_Component (Entity (S)))
996ae0b0 9989 and then not Discriminant_Checks_Suppressed (T)
6510f4c9 9990 and then not Init_Component
996ae0b0
RK		 9991 then
9992 Set_Do_Discriminant_Check (N);
9993 end if;
9994
9995 if Ekind (Entity (S)) = E_Void then
9996 Error_Msg_N ("premature use of component", S);
9997 end if;
9998
9999 -- If the prefix is a record conversion, this may be a renamed
10000 -- discriminant whose bounds differ from those of the original
10001 -- one, so we must ensure that a range check is performed.
10002
10003 if Nkind (P) = N_Type_Conversion
10004 and then Ekind (Entity (S)) = E_Discriminant
fbf5a39b 10005 and then Is_Discrete_Type (Typ)
996ae0b0
RK		 10006 then
10007 Set_Etype (N, Base_Type (Typ));
10008 end if;
10009
10010 -- Note: No Eval processing is required, because the prefix is of a
10011 -- record type, or protected type, and neither can possibly be static.
10012
c2a2dbcc
RD		 10013 -- If the record type is atomic, and the component is non-atomic, then
10014 -- this is worth a warning, since we have a situation where the access
10015 -- to the component may cause extra read/writes of the atomic array
10016 -- object, or partial word accesses, both of which may be unexpected.
c28408b7
RD		 10017
10018 if Nkind (N) = N_Selected_Component
c2a2dbcc
RD		 10019 and then Is_Atomic_Ref_With_Address (N)
10020 and then not Is_Atomic (Entity (S))
10021 and then not Is_Atomic (Etype (Entity (S)))
c28408b7 10022 then
54c04d6c 10023 Error_Msg_N
c2a2dbcc
RD		 10024 ("??access to non-atomic component of atomic record",
10025 Prefix (N));
54c04d6c 10026 Error_Msg_N
c2a2dbcc
RD		 10027 ("\??may cause unexpected accesses to atomic object",
10028 Prefix (N));
c28408b7 10029 end if;
54c04d6c 10030
dec6faf1 10031 Analyze_Dimension (N);
996ae0b0
RK		 10032 end Resolve_Selected_Component;
10033
10034 -------------------
10035 -- Resolve_Shift --
10036 -------------------
10037
10038 procedure Resolve_Shift (N : Node_Id; Typ : Entity_Id) is
10039 B_Typ : constant Entity_Id := Base_Type (Typ);
10040 L : constant Node_Id := Left_Opnd (N);
10041 R : constant Node_Id := Right_Opnd (N);
10042
10043 begin
10044 -- We do the resolution using the base type, because intermediate values
10045 -- in expressions always are of the base type, not a subtype of it.
10046
10047 Resolve (L, B_Typ);
10048 Resolve (R, Standard_Natural);
10049
10050 Check_Unset_Reference (L);
10051 Check_Unset_Reference (R);
10052
10053 Set_Etype (N, B_Typ);
fbf5a39b 10054 Generate_Operator_Reference (N, B_Typ);
996ae0b0
RK		 10055 Eval_Shift (N);
10056 end Resolve_Shift;
10057
10058 ---------------------------
10059 -- Resolve_Short_Circuit --
10060 ---------------------------
10061
10062 procedure Resolve_Short_Circuit (N : Node_Id; Typ : Entity_Id) is
10063 B_Typ : constant Entity_Id := Base_Type (Typ);
10064 L : constant Node_Id := Left_Opnd (N);
10065 R : constant Node_Id := Right_Opnd (N);
10066
10067 begin
064f4527 10068 -- Ensure all actions associated with the left operand (e.g.
937e9676
AC		 10069 -- finalization of transient objects) are fully evaluated locally within
10070 -- an expression with actions. This is particularly helpful for coverage
10071 -- analysis. However this should not happen in generics or if option
10072 -- Minimize_Expression_With_Actions is set.
064f4527 10073
f916243b 10074 if Expander_Active and not Minimize_Expression_With_Actions then
064f4527
TQ		 10075 declare
10076 Reloc_L : constant Node_Id := Relocate_Node (L);
10077 begin
10078 Save_Interps (Old_N => L, New_N => Reloc_L);
10079
10080 Rewrite (L,
10081 Make_Expression_With_Actions (Sloc (L),
10082 Actions => New_List,
10083 Expression => Reloc_L));
10084
10085 -- Set Comes_From_Source on L to preserve warnings for unset
10086 -- reference.
10087
10088 Set_Comes_From_Source (L, Comes_From_Source (Reloc_L));
10089 end;
10090 end if;
10091
996ae0b0
RK		 10092 Resolve (L, B_Typ);
10093 Resolve (R, B_Typ);
10094
45fc7ddb
HK		 10095 -- Check for issuing warning for always False assert/check, this happens
10096 -- when assertions are turned off, in which case the pragma Assert/Check
36fcf362
RD		 10097 -- was transformed into:
10098
10099 -- if False and then <condition> then ...
10100
10101 -- and we detect this pattern
10102
10103 if Warn_On_Assertion_Failure
10104 and then Is_Entity_Name (R)
10105 and then Entity (R) = Standard_False
10106 and then Nkind (Parent (N)) = N_If_Statement
10107 and then Nkind (N) = N_And_Then
10108 and then Is_Entity_Name (L)
10109 and then Entity (L) = Standard_False
10110 then
10111 declare
10112 Orig : constant Node_Id := Original_Node (Parent (N));
45fc7ddb 10113
36fcf362 10114 begin
20a65dcb
RD		 10115 -- Special handling of Asssert pragma
10116
36fcf362 10117 if Nkind (Orig) = N_Pragma
6e759c2a 10118 and then Pragma_Name (Orig) = Name_Assert
36fcf362 10119 then
36fcf362
RD		 10120 declare
10121 Expr : constant Node_Id :=
10122 Original_Node
10123 (Expression
10124 (First (Pragma_Argument_Associations (Orig))));
20a65dcb 10125
36fcf362 10126 begin
20a65dcb
RD		 10127 -- Don't warn if original condition is explicit False,
10128 -- since obviously the failure is expected in this case.
10129
36fcf362
RD		 10130 if Is_Entity_Name (Expr)
10131 and then Entity (Expr) = Standard_False
10132 then
10133 null;
51bf9bdf 10134
20a65dcb
RD		 10135 -- Issue warning. We do not want the deletion of the
10136 -- IF/AND-THEN to take this message with it. We achieve this
10137 -- by making sure that the expanded code points to the Sloc
10138 -- of the expression, not the original pragma.
10139
10140 else
8a06151a
RD		 10141 -- Note: Use Error_Msg_F here rather than Error_Msg_N.
10142 -- The source location of the expression is not usually
10143 -- the best choice here. For example, it gets located on
10144 -- the last AND keyword in a chain of boolean expressiond
10145 -- AND'ed together. It is best to put the message on the
10146 -- first character of the assertion, which is the effect
10147 -- of the First_Node call here.
10148
ca20a08e 10149 Error_Msg_F
685bc70f 10150 ("?A?assertion would fail at run time!",
51bf9bdf
AC		 10151 Expression
10152 (First (Pragma_Argument_Associations (Orig))));
36fcf362
RD		 10153 end if;
10154 end;
45fc7ddb
HK		 10155
10156 -- Similar processing for Check pragma
10157
10158 elsif Nkind (Orig) = N_Pragma
6e759c2a 10159 and then Pragma_Name (Orig) = Name_Check
45fc7ddb
HK		 10160 then
10161 -- Don't want to warn if original condition is explicit False
10162
10163 declare
10164 Expr : constant Node_Id :=
324ac540
AC		 10165 Original_Node
10166 (Expression
10167 (Next (First (Pragma_Argument_Associations (Orig)))));
45fc7ddb
HK		 10168 begin
10169 if Is_Entity_Name (Expr)
10170 and then Entity (Expr) = Standard_False
10171 then
10172 null;
8a06151a
RD		 10173
10174 -- Post warning
10175
45fc7ddb 10176 else
8a06151a
RD		 10177 -- Again use Error_Msg_F rather than Error_Msg_N, see
10178 -- comment above for an explanation of why we do this.
10179
ca20a08e 10180 Error_Msg_F
685bc70f 10181 ("?A?check would fail at run time!",
51bf9bdf
AC		 10182 Expression
10183 (Last (Pragma_Argument_Associations (Orig))));
45fc7ddb
HK		 10184 end if;
10185 end;
36fcf362
RD		 10186 end if;
10187 end;
10188 end if;
10189
10190 -- Continue with processing of short circuit
10191
996ae0b0
RK		 10192 Check_Unset_Reference (L);
10193 Check_Unset_Reference (R);
10194
10195 Set_Etype (N, B_Typ);
10196 Eval_Short_Circuit (N);
10197 end Resolve_Short_Circuit;
10198
10199 -------------------
10200 -- Resolve_Slice --
10201 -------------------
10202
10203 procedure Resolve_Slice (N : Node_Id; Typ : Entity_Id) is
996ae0b0 10204 Drange : constant Node_Id := Discrete_Range (N);
5f44f0d4 10205 Name : constant Node_Id := Prefix (N);
996ae0b0 10206 Array_Type : Entity_Id := Empty;
800da977 10207 Dexpr : Node_Id := Empty;
5f44f0d4 10208 Index_Type : Entity_Id;
996ae0b0
RK		 10209
10210 begin
10211 if Is_Overloaded (Name) then
10212
d81b4bfe
TQ		 10213 -- Use the context type to select the prefix that yields the correct
10214 -- array type.
996ae0b0
RK		 10215
10216 declare
10217 I : Interp_Index;
10218 I1 : Interp_Index := 0;
10219 It : Interp;
10220 P : constant Node_Id := Prefix (N);
10221 Found : Boolean := False;
10222
10223 begin
10224 Get_First_Interp (P, I, It);
996ae0b0 10225 while Present (It.Typ) loop
996ae0b0
RK		 10226 if (Is_Array_Type (It.Typ)
10227 and then Covers (Typ, It.Typ))
10228 or else (Is_Access_Type (It.Typ)
10229 and then Is_Array_Type (Designated_Type (It.Typ))
10230 and then Covers (Typ, Designated_Type (It.Typ)))
10231 then
10232 if Found then
10233 It := Disambiguate (P, I1, I, Any_Type);
10234
10235 if It = No_Interp then
10236 Error_Msg_N ("ambiguous prefix for slicing", N);
10237 Set_Etype (N, Typ);
10238 return;
10239 else
10240 Found := True;
10241 Array_Type := It.Typ;
10242 I1 := I;
10243 end if;
10244 else
10245 Found := True;
10246 Array_Type := It.Typ;
10247 I1 := I;
10248 end if;
10249 end if;
10250
10251 Get_Next_Interp (I, It);
10252 end loop;
10253 end;
10254
10255 else
10256 Array_Type := Etype (Name);
10257 end if;
10258
10259 Resolve (Name, Array_Type);
10260
10261 if Is_Access_Type (Array_Type) then
10262 Apply_Access_Check (N);
10263 Array_Type := Designated_Type (Array_Type);
10264
c8ef728f
ES		 10265 -- If the prefix is an access to an unconstrained array, we must use
10266 -- the actual subtype of the object to perform the index checks. The
10267 -- object denoted by the prefix is implicit in the node, so we build
10268 -- an explicit representation for it in order to compute the actual
10269 -- subtype.
82c80734
RD		 10270
10271 if not Is_Constrained (Array_Type) then
10272 Remove_Side_Effects (Prefix (N));
10273
10274 declare
10275 Obj : constant Node_Id :=
10276 Make_Explicit_Dereference (Sloc (N),
10277 Prefix => New_Copy_Tree (Prefix (N)));
10278 begin
10279 Set_Etype (Obj, Array_Type);
10280 Set_Parent (Obj, Parent (N));
10281 Array_Type := Get_Actual_Subtype (Obj);
10282 end;
10283 end if;
10284
996ae0b0 10285 elsif Is_Entity_Name (Name)
6c994759 10286 or else Nkind (Name) = N_Explicit_Dereference
996ae0b0
RK		 10287 or else (Nkind (Name) = N_Function_Call
10288 and then not Is_Constrained (Etype (Name)))
10289 then
10290 Array_Type := Get_Actual_Subtype (Name);
aa5147f0
ES		 10291
10292 -- If the name is a selected component that depends on discriminants,
10293 -- build an actual subtype for it. This can happen only when the name
10294 -- itself is overloaded; otherwise the actual subtype is created when
10295 -- the selected component is analyzed.
10296
10297 elsif Nkind (Name) = N_Selected_Component
10298 and then Full_Analysis
10299 and then Depends_On_Discriminant (First_Index (Array_Type))
10300 then
10301 declare
10302 Act_Decl : constant Node_Id :=
10303 Build_Actual_Subtype_Of_Component (Array_Type, Name);
10304 begin
10305 Insert_Action (N, Act_Decl);
10306 Array_Type := Defining_Identifier (Act_Decl);
10307 end;
d79e621a
GD		 10308
10309 -- Maybe this should just be "else", instead of checking for the
5cc9353d
RD		 10310 -- specific case of slice??? This is needed for the case where the
10311 -- prefix is an Image attribute, which gets expanded to a slice, and so
10312 -- has a constrained subtype which we want to use for the slice range
10313 -- check applied below (the range check won't get done if the
10314 -- unconstrained subtype of the 'Image is used).
d79e621a
GD		 10315
10316 elsif Nkind (Name) = N_Slice then
10317 Array_Type := Etype (Name);
996ae0b0
RK		 10318 end if;
10319
800da977
AC		 10320 -- Obtain the type of the array index
10321
10322 if Ekind (Array_Type) = E_String_Literal_Subtype then
10323 Index_Type := Etype (String_Literal_Low_Bound (Array_Type));
10324 else
10325 Index_Type := Etype (First_Index (Array_Type));
10326 end if;
10327
996ae0b0
RK		 10328 -- If name was overloaded, set slice type correctly now
10329
10330 Set_Etype (N, Array_Type);
10331
800da977
AC		 10332 -- Handle the generation of a range check that compares the array index
10333 -- against the discrete_range. The check is not applied to internally
10334 -- built nodes associated with the expansion of dispatch tables. Check
10335 -- that Ada.Tags has already been loaded to avoid extra dependencies on
10336 -- the unit.
10337
10338 if Tagged_Type_Expansion
10339 and then RTU_Loaded (Ada_Tags)
10340 and then Nkind (Prefix (N)) = N_Selected_Component
10341 and then Present (Entity (Selector_Name (Prefix (N))))
10342 and then Entity (Selector_Name (Prefix (N))) =
10343 RTE_Record_Component (RE_Prims_Ptr)
10344 then
10345 null;
996ae0b0 10346
800da977
AC		 10347 -- The discrete_range is specified by a subtype indication. Create a
10348 -- shallow copy and inherit the type, parent and source location from
10349 -- the discrete_range. This ensures that the range check is inserted
10350 -- relative to the slice and that the runtime exception points to the
10351 -- proper construct.
5f44f0d4 10352
800da977
AC		 10353 elsif Is_Entity_Name (Drange) then
10354 Dexpr := New_Copy (Scalar_Range (Entity (Drange)));
996ae0b0 10355
800da977
AC		 10356 Set_Etype (Dexpr, Etype (Drange));
10357 Set_Parent (Dexpr, Parent (Drange));
10358 Set_Sloc (Dexpr, Sloc (Drange));
dbe945f1 10359
800da977
AC		 10360 -- The discrete_range is a regular range. Resolve the bounds and remove
10361 -- their side effects.
dbe945f1 10362
800da977
AC		 10363 else
10364 Resolve (Drange, Base_Type (Index_Type));
10365
10366 if Nkind (Drange) = N_Range then
10367 Force_Evaluation (Low_Bound (Drange));
cae81f17 10368 Force_Evaluation (High_Bound (Drange));
0669bebe 10369
800da977 10370 Dexpr := Drange;
996ae0b0
RK		 10371 end if;
10372 end if;
10373
800da977
AC		 10374 if Present (Dexpr) then
10375 Apply_Range_Check (Dexpr, Index_Type);
10376 end if;
10377
996ae0b0 10378 Set_Slice_Subtype (N);
aa180613 10379
ea034236
AC		 10380 -- Check bad use of type with predicates
10381
24de083f
AC		 10382 declare
10383 Subt : Entity_Id;
10384
10385 begin
10386 if Nkind (Drange) = N_Subtype_Indication
b330e3c8 10387 and then Has_Predicates (Entity (Subtype_Mark (Drange)))
24de083f
AC		 10388 then
10389 Subt := Entity (Subtype_Mark (Drange));
24de083f
AC		 10390 else
10391 Subt := Etype (Drange);
10392 end if;
10393
10394 if Has_Predicates (Subt) then
10395 Bad_Predicated_Subtype_Use
10396 ("subtype& has predicate, not allowed in slice", Drange, Subt);
10397 end if;
10398 end;
ea034236
AC		 10399
10400 -- Otherwise here is where we check suspicious indexes
10401
24de083f 10402 if Nkind (Drange) = N_Range then
aa180613
RD		 10403 Warn_On_Suspicious_Index (Name, Low_Bound (Drange));
10404 Warn_On_Suspicious_Index (Name, High_Bound (Drange));
10405 end if;
10406
dec6faf1 10407 Analyze_Dimension (N);
996ae0b0 10408 Eval_Slice (N);
996ae0b0
RK		 10409 end Resolve_Slice;
10410
10411 ----------------------------
10412 -- Resolve_String_Literal --
10413 ----------------------------
10414
10415 procedure Resolve_String_Literal (N : Node_Id; Typ : Entity_Id) is
10416 C_Typ : constant Entity_Id := Component_Type (Typ);
10417 R_Typ : constant Entity_Id := Root_Type (C_Typ);
10418 Loc : constant Source_Ptr := Sloc (N);
10419 Str : constant String_Id := Strval (N);
10420 Strlen : constant Nat := String_Length (Str);
10421 Subtype_Id : Entity_Id;
10422 Need_Check : Boolean;
10423
10424 begin
10425 -- For a string appearing in a concatenation, defer creation of the
10426 -- string_literal_subtype until the end of the resolution of the
c8ef728f
ES		 10427 -- concatenation, because the literal may be constant-folded away. This
10428 -- is a useful optimization for long concatenation expressions.
996ae0b0 10429
c8ef728f 10430 -- If the string is an aggregate built for a single character (which
996ae0b0 10431 -- happens in a non-static context) or a is null string to which special
c8ef728f
ES		 10432 -- checks may apply, we build the subtype. Wide strings must also get a
10433 -- string subtype if they come from a one character aggregate. Strings
996ae0b0
RK		 10434 -- generated by attributes might be static, but it is often hard to
10435 -- determine whether the enclosing context is static, so we generate
10436 -- subtypes for them as well, thus losing some rarer optimizations ???
10437 -- Same for strings that come from a static conversion.
10438
10439 Need_Check :=
10440 (Strlen = 0 and then Typ /= Standard_String)
10441 or else Nkind (Parent (N)) /= N_Op_Concat
10442 or else (N /= Left_Opnd (Parent (N))
10443 and then N /= Right_Opnd (Parent (N)))
82c80734
RD		 10444 or else ((Typ = Standard_Wide_String
10445 or else Typ = Standard_Wide_Wide_String)
996ae0b0
RK		 10446 and then Nkind (Original_Node (N)) /= N_String_Literal);
10447
d81b4bfe
TQ		 10448 -- If the resolving type is itself a string literal subtype, we can just
10449 -- reuse it, since there is no point in creating another.
996ae0b0
RK		 10450
10451 if Ekind (Typ) = E_String_Literal_Subtype then
10452 Subtype_Id := Typ;
10453
10454 elsif Nkind (Parent (N)) = N_Op_Concat
10455 and then not Need_Check
45fc7ddb
HK		 10456 and then not Nkind_In (Original_Node (N), N_Character_Literal,
10457 N_Attribute_Reference,
10458 N_Qualified_Expression,
10459 N_Type_Conversion)
996ae0b0
RK		 10460 then
10461 Subtype_Id := Typ;
10462
79904ebc
AC		 10463 -- Do not generate a string literal subtype for the default expression
10464 -- of a formal parameter in GNATprove mode. This is because the string
10465 -- subtype is associated with the freezing actions of the subprogram,
10466 -- however freezing is disabled in GNATprove mode and as a result the
10467 -- subtype is unavailable.
10468
10469 elsif GNATprove_Mode
10470 and then Nkind (Parent (N)) = N_Parameter_Specification
10471 then
10472 Subtype_Id := Typ;
10473
996ae0b0
RK		 10474 -- Otherwise we must create a string literal subtype. Note that the
10475 -- whole idea of string literal subtypes is simply to avoid the need
10476 -- for building a full fledged array subtype for each literal.
45fc7ddb 10477
996ae0b0
RK		 10478 else
10479 Set_String_Literal_Subtype (N, Typ);
10480 Subtype_Id := Etype (N);
10481 end if;
10482
10483 if Nkind (Parent (N)) /= N_Op_Concat
10484 or else Need_Check
10485 then
10486 Set_Etype (N, Subtype_Id);
10487 Eval_String_Literal (N);
10488 end if;
10489
10490 if Is_Limited_Composite (Typ)
10491 or else Is_Private_Composite (Typ)
10492 then
10493 Error_Msg_N ("string literal not available for private array", N);
10494 Set_Etype (N, Any_Type);
10495 return;
10496 end if;
10497
d81b4bfe
TQ		 10498 -- The validity of a null string has been checked in the call to
10499 -- Eval_String_Literal.
996ae0b0
RK		 10500
10501 if Strlen = 0 then
10502 return;
10503
c8ef728f
ES		 10504 -- Always accept string literal with component type Any_Character, which
10505 -- occurs in error situations and in comparisons of literals, both of
10506 -- which should accept all literals.
996ae0b0
RK		 10507
10508 elsif R_Typ = Any_Character then
10509 return;
10510
f3d57416
RW		 10511 -- If the type is bit-packed, then we always transform the string
10512 -- literal into a full fledged aggregate.
996ae0b0
RK		 10513
10514 elsif Is_Bit_Packed_Array (Typ) then
10515 null;
10516
82c80734 10517 -- Deal with cases of Wide_Wide_String, Wide_String, and String
996ae0b0
RK		 10518
10519 else
82c80734
RD		 10520 -- For Standard.Wide_Wide_String, or any other type whose component
10521 -- type is Standard.Wide_Wide_Character, we know that all the
996ae0b0
RK		 10522 -- characters in the string must be acceptable, since the parser
10523 -- accepted the characters as valid character literals.
10524
82c80734 10525 if R_Typ = Standard_Wide_Wide_Character then
996ae0b0
RK		 10526 null;
10527
c8ef728f
ES		 10528 -- For the case of Standard.String, or any other type whose component
10529 -- type is Standard.Character, we must make sure that there are no
10530 -- wide characters in the string, i.e. that it is entirely composed
10531 -- of characters in range of type Character.
996ae0b0 10532
c8ef728f
ES		 10533 -- If the string literal is the result of a static concatenation, the
10534 -- test has already been performed on the components, and need not be
10535 -- repeated.
996ae0b0
RK		 10536
10537 elsif R_Typ = Standard_Character
10538 and then Nkind (Original_Node (N)) /= N_Op_Concat
10539 then
10540 for J in 1 .. Strlen loop
10541 if not In_Character_Range (Get_String_Char (Str, J)) then
10542
10543 -- If we are out of range, post error. This is one of the
10544 -- very few places that we place the flag in the middle of
d81b4bfe
TQ		 10545 -- a token, right under the offending wide character. Not
10546 -- quite clear if this is right wrt wide character encoding
a90bd866 10547 -- sequences, but it's only an error message.
996ae0b0
RK		 10548
10549 Error_Msg
82c80734
RD		 10550 ("literal out of range of type Standard.Character",
10551 Source_Ptr (Int (Loc) + J));
10552 return;
10553 end if;
10554 end loop;
10555
10556 -- For the case of Standard.Wide_String, or any other type whose
10557 -- component type is Standard.Wide_Character, we must make sure that
10558 -- there are no wide characters in the string, i.e. that it is
10559 -- entirely composed of characters in range of type Wide_Character.
10560
10561 -- If the string literal is the result of a static concatenation,
10562 -- the test has already been performed on the components, and need
10563 -- not be repeated.
10564
10565 elsif R_Typ = Standard_Wide_Character
10566 and then Nkind (Original_Node (N)) /= N_Op_Concat
10567 then
10568 for J in 1 .. Strlen loop
10569 if not In_Wide_Character_Range (Get_String_Char (Str, J)) then
10570
10571 -- If we are out of range, post error. This is one of the
10572 -- very few places that we place the flag in the middle of
10573 -- a token, right under the offending wide character.
10574
10575 -- This is not quite right, because characters in general
10576 -- will take more than one character position ???
10577
10578 Error_Msg
10579 ("literal out of range of type Standard.Wide_Character",
996ae0b0
RK		 10580 Source_Ptr (Int (Loc) + J));
10581 return;
10582 end if;
10583 end loop;
10584
10585 -- If the root type is not a standard character, then we will convert
10586 -- the string into an aggregate and will let the aggregate code do
82c80734 10587 -- the checking. Standard Wide_Wide_Character is also OK here.
996ae0b0
RK		 10588
10589 else
10590 null;
996ae0b0
RK		 10591 end if;
10592
c8ef728f
ES		 10593 -- See if the component type of the array corresponding to the string
10594 -- has compile time known bounds. If yes we can directly check
10595 -- whether the evaluation of the string will raise constraint error.
10596 -- Otherwise we need to transform the string literal into the
5cc9353d
RD		 10597 -- corresponding character aggregate and let the aggregate code do
10598 -- the checking.
996ae0b0 10599
45fc7ddb
HK		 10600 if Is_Standard_Character_Type (R_Typ) then
10601
996ae0b0
RK		 10602 -- Check for the case of full range, where we are definitely OK
10603
10604 if Component_Type (Typ) = Base_Type (Component_Type (Typ)) then
10605 return;
10606 end if;
10607
10608 -- Here the range is not the complete base type range, so check
10609
10610 declare
10611 Comp_Typ_Lo : constant Node_Id :=
10612 Type_Low_Bound (Component_Type (Typ));
10613 Comp_Typ_Hi : constant Node_Id :=
10614 Type_High_Bound (Component_Type (Typ));
10615
10616 Char_Val : Uint;
10617
10618 begin
10619 if Compile_Time_Known_Value (Comp_Typ_Lo)
10620 and then Compile_Time_Known_Value (Comp_Typ_Hi)
10621 then
10622 for J in 1 .. Strlen loop
10623 Char_Val := UI_From_Int (Int (Get_String_Char (Str, J)));
10624
10625 if Char_Val < Expr_Value (Comp_Typ_Lo)
10626 or else Char_Val > Expr_Value (Comp_Typ_Hi)
10627 then
10628 Apply_Compile_Time_Constraint_Error
324ac540
AC		 10629 (N, "character out of range??",
10630 CE_Range_Check_Failed,
996ae0b0
RK		 10631 Loc => Source_Ptr (Int (Loc) + J));
10632 end if;
10633 end loop;
10634
10635 return;
10636 end if;
10637 end;
10638 end if;
10639 end if;
10640
10641 -- If we got here we meed to transform the string literal into the
10642 -- equivalent qualified positional array aggregate. This is rather
10643 -- heavy artillery for this situation, but it is hard work to avoid.
10644
10645 declare
fbf5a39b 10646 Lits : constant List_Id := New_List;
996ae0b0
RK		 10647 P : Source_Ptr := Loc + 1;
10648 C : Char_Code;
10649
10650 begin
c8ef728f
ES		 10651 -- Build the character literals, we give them source locations that
10652 -- correspond to the string positions, which is a bit tricky given
10653 -- the possible presence of wide character escape sequences.
996ae0b0
RK		 10654
10655 for J in 1 .. Strlen loop
10656 C := Get_String_Char (Str, J);
10657 Set_Character_Literal_Name (C);
10658
10659 Append_To (Lits,
82c80734
RD		 10660 Make_Character_Literal (P,
10661 Chars => Name_Find,
10662 Char_Literal_Value => UI_From_CC (C)));
996ae0b0
RK		 10663
10664 if In_Character_Range (C) then
10665 P := P + 1;
10666
10667 -- Should we have a call to Skip_Wide here ???
5cc9353d 10668
996ae0b0
RK		 10669 -- ??? else
10670 -- Skip_Wide (P);
10671
10672 end if;
10673 end loop;
10674
10675 Rewrite (N,
10676 Make_Qualified_Expression (Loc,
e4494292 10677 Subtype_Mark => New_Occurrence_Of (Typ, Loc),
996ae0b0
RK		 10678 Expression =>
10679 Make_Aggregate (Loc, Expressions => Lits)));
10680
10681 Analyze_And_Resolve (N, Typ);
10682 end;
10683 end Resolve_String_Literal;
10684
ae33543c
ES		 10685 -------------------------
10686 -- Resolve_Target_Name --
10687 -------------------------
10688
10689 procedure Resolve_Target_Name (N : Node_Id; Typ : Entity_Id) is
10690 begin
10691 Set_Etype (N, Typ);
10692 end Resolve_Target_Name;
10693
996ae0b0
RK		 10694 -----------------------------
10695 -- Resolve_Type_Conversion --
10696 -----------------------------
10697
10698 procedure Resolve_Type_Conversion (N : Node_Id; Typ : Entity_Id) is
4b2d2c13
AC		 10699 Conv_OK : constant Boolean := Conversion_OK (N);
10700 Operand : constant Node_Id := Expression (N);
b7d1f17f
HK		 10701 Operand_Typ : constant Entity_Id := Etype (Operand);
10702 Target_Typ : constant Entity_Id := Etype (N);
996ae0b0 10703 Rop : Node_Id;
fbf5a39b
AC		 10704 Orig_N : Node_Id;
10705 Orig_T : Node_Id;
996ae0b0 10706
ae2aa109
AC		 10707 Test_Redundant : Boolean := Warn_On_Redundant_Constructs;
10708 -- Set to False to suppress cases where we want to suppress the test
10709 -- for redundancy to avoid possible false positives on this warning.
10710
996ae0b0 10711 begin
996ae0b0 10712 if not Conv_OK
b7d1f17f 10713 and then not Valid_Conversion (N, Target_Typ, Operand)
996ae0b0
RK		 10714 then
10715 return;
10716 end if;
10717
ae2aa109
AC		 10718 -- If the Operand Etype is Universal_Fixed, then the conversion is
10719 -- never redundant. We need this check because by the time we have
10720 -- finished the rather complex transformation, the conversion looks
10721 -- redundant when it is not.
10722
10723 if Operand_Typ = Universal_Fixed then
10724 Test_Redundant := False;
10725
10726 -- If the operand is marked as Any_Fixed, then special processing is
10727 -- required. This is also a case where we suppress the test for a
10728 -- redundant conversion, since most certainly it is not redundant.
10729
10730 elsif Operand_Typ = Any_Fixed then
10731 Test_Redundant := False;
996ae0b0
RK		 10732
10733 -- Mixed-mode operation involving a literal. Context must be a fixed
10734 -- type which is applied to the literal subsequently.
10735
cccb761b
AC		 10736 -- Multiplication and division involving two fixed type operands must
10737 -- yield a universal real because the result is computed in arbitrary
10738 -- precision.
10739
10740 if Is_Fixed_Point_Type (Typ)
10741 and then Nkind_In (Operand, N_Op_Divide, N_Op_Multiply)
10742 and then Etype (Left_Opnd (Operand)) = Any_Fixed
10743 and then Etype (Right_Opnd (Operand)) = Any_Fixed
10744 then
996ae0b0
RK		 10745 Set_Etype (Operand, Universal_Real);
10746
10747 elsif Is_Numeric_Type (Typ)
45fc7ddb 10748 and then Nkind_In (Operand, N_Op_Multiply, N_Op_Divide)
996ae0b0 10749 and then (Etype (Right_Opnd (Operand)) = Universal_Real
45fc7ddb
HK		 10750 or else
10751 Etype (Left_Opnd (Operand)) = Universal_Real)
996ae0b0 10752 then
a77842bd
TQ		 10753 -- Return if expression is ambiguous
10754
996ae0b0 10755 if Unique_Fixed_Point_Type (N) = Any_Type then
a77842bd 10756 return;
82c80734 10757
a77842bd
TQ		 10758 -- If nothing else, the available fixed type is Duration
10759
10760 else
996ae0b0
RK		 10761 Set_Etype (Operand, Standard_Duration);
10762 end if;
10763
bc5f3720 10764 -- Resolve the real operand with largest available precision
9ebe3743 10765
996ae0b0
RK		 10766 if Etype (Right_Opnd (Operand)) = Universal_Real then
10767 Rop := New_Copy_Tree (Right_Opnd (Operand));
10768 else
10769 Rop := New_Copy_Tree (Left_Opnd (Operand));
10770 end if;
10771
9ebe3743 10772 Resolve (Rop, Universal_Real);
996ae0b0 10773
82c80734
RD		 10774 -- If the operand is a literal (it could be a non-static and
10775 -- illegal exponentiation) check whether the use of Duration
10776 -- is potentially inaccurate.
10777
10778 if Nkind (Rop) = N_Real_Literal
10779 and then Realval (Rop) /= Ureal_0
996ae0b0
RK		 10780 and then abs (Realval (Rop)) < Delta_Value (Standard_Duration)
10781 then
aa180613 10782 Error_Msg_N
67b8ac46
AC		 10783 ("??universal real operand can only "
10784 & "be interpreted as Duration!", Rop);
aa180613 10785 Error_Msg_N
324ac540 10786 ("\??precision will be lost in the conversion!", Rop);
996ae0b0
RK		 10787 end if;
10788
891a6e79
AC		 10789 elsif Is_Numeric_Type (Typ)
10790 and then Nkind (Operand) in N_Op
10791 and then Unique_Fixed_Point_Type (N) /= Any_Type
10792 then
10793 Set_Etype (Operand, Standard_Duration);
10794
996ae0b0
RK		 10795 else
10796 Error_Msg_N ("invalid context for mixed mode operation", N);
10797 Set_Etype (Operand, Any_Type);
10798 return;
10799 end if;
10800 end if;
10801
fbf5a39b 10802 Resolve (Operand);
996ae0b0 10803
2ba431e5
YM		 10804 -- In SPARK, a type conversion between array types should be restricted
10805 -- to types which have matching static bounds.
b0186f71 10806
7b98672f
YM		 10807 -- Protect call to Matching_Static_Array_Bounds to avoid costly
10808 -- operation if not needed.
10809
6480338a 10810 if Restriction_Check_Required (SPARK_05)
7b98672f 10811 and then Is_Array_Type (Target_Typ)
b0186f71 10812 and then Is_Array_Type (Operand_Typ)
db72f10a 10813 and then Operand_Typ /= Any_Composite -- or else Operand in error
b0186f71
AC		 10814 and then not Matching_Static_Array_Bounds (Target_Typ, Operand_Typ)
10815 then
ce5ba43a 10816 Check_SPARK_05_Restriction
fe5d3068 10817 ("array types should have matching static bounds", N);
b0186f71
AC		 10818 end if;
10819
e24329cd
YM		 10820 -- In formal mode, the operand of an ancestor type conversion must be an
10821 -- object (not an expression).
10822
10823 if Is_Tagged_Type (Target_Typ)
10824 and then not Is_Class_Wide_Type (Target_Typ)
10825 and then Is_Tagged_Type (Operand_Typ)
10826 and then not Is_Class_Wide_Type (Operand_Typ)
10827 and then Is_Ancestor (Target_Typ, Operand_Typ)
ce5ba43a 10828 and then not Is_SPARK_05_Object_Reference (Operand)
e24329cd 10829 then
ce5ba43a 10830 Check_SPARK_05_Restriction ("object required", Operand);
e24329cd
YM		 10831 end if;
10832
dec6faf1
AC		 10833 Analyze_Dimension (N);
10834
996ae0b0 10835 -- Note: we do the Eval_Type_Conversion call before applying the
d81b4bfe
TQ		 10836 -- required checks for a subtype conversion. This is important, since
10837 -- both are prepared under certain circumstances to change the type
10838 -- conversion to a constraint error node, but in the case of
10839 -- Eval_Type_Conversion this may reflect an illegality in the static
10840 -- case, and we would miss the illegality (getting only a warning
10841 -- message), if we applied the type conversion checks first.
996ae0b0
RK		 10842
10843 Eval_Type_Conversion (N);
10844
d81b4bfe
TQ		 10845 -- Even when evaluation is not possible, we may be able to simplify the
10846 -- conversion or its expression. This needs to be done before applying
10847 -- checks, since otherwise the checks may use the original expression
10848 -- and defeat the simplifications. This is specifically the case for
10849 -- elimination of the floating-point Truncation attribute in
10850 -- float-to-int conversions.
0669bebe
GB		 10851
10852 Simplify_Type_Conversion (N);
10853
d81b4bfe
TQ		 10854 -- If after evaluation we still have a type conversion, then we may need
10855 -- to apply checks required for a subtype conversion.
996ae0b0
RK		 10856
10857 -- Skip these type conversion checks if universal fixed operands
10858 -- operands involved, since range checks are handled separately for
10859 -- these cases (in the appropriate Expand routines in unit Exp_Fixd).
10860
10861 if Nkind (N) = N_Type_Conversion
b7d1f17f
HK		 10862 and then not Is_Generic_Type (Root_Type (Target_Typ))
10863 and then Target_Typ /= Universal_Fixed
10864 and then Operand_Typ /= Universal_Fixed
996ae0b0
RK		 10865 then
10866 Apply_Type_Conversion_Checks (N);
10867 end if;
10868
d81b4bfe
TQ		 10869 -- Issue warning for conversion of simple object to its own type. We
10870 -- have to test the original nodes, since they may have been rewritten
10871 -- by various optimizations.
fbf5a39b
AC		 10872
10873 Orig_N := Original_Node (N);
996ae0b0 10874
ae2aa109
AC		 10875 -- Here we test for a redundant conversion if the warning mode is
10876 -- active (and was not locally reset), and we have a type conversion
10877 -- from source not appearing in a generic instance.
10878
10879 if Test_Redundant
fbf5a39b 10880 and then Nkind (Orig_N) = N_Type_Conversion
ae2aa109 10881 and then Comes_From_Source (Orig_N)
5453d5bd 10882 and then not In_Instance
996ae0b0 10883 then
fbf5a39b 10884 Orig_N := Original_Node (Expression (Orig_N));
b7d1f17f 10885 Orig_T := Target_Typ;
fbf5a39b
AC		 10886
10887 -- If the node is part of a larger expression, the Target_Type
10888 -- may not be the original type of the node if the context is a
10889 -- condition. Recover original type to see if conversion is needed.
10890
10891 if Is_Boolean_Type (Orig_T)
10892 and then Nkind (Parent (N)) in N_Op
10893 then
10894 Orig_T := Etype (Parent (N));
10895 end if;
10896
4adf3c50 10897 -- If we have an entity name, then give the warning if the entity
ae2aa109
AC		 10898 -- is the right type, or if it is a loop parameter covered by the
10899 -- original type (that's needed because loop parameters have an
10900 -- odd subtype coming from the bounds).
10901
10902 if (Is_Entity_Name (Orig_N)
98bf4cf4
AC		 10903 and then
10904 (Etype (Entity (Orig_N)) = Orig_T
10905 or else
10906 (Ekind (Entity (Orig_N)) = E_Loop_Parameter
10907 and then Covers (Orig_T, Etype (Entity (Orig_N))))))
ae2aa109 10908
477bd732 10909 -- If not an entity, then type of expression must match
ae2aa109
AC		 10910
10911 or else Etype (Orig_N) = Orig_T
fbf5a39b 10912 then
4b2d2c13
AC		 10913 -- One more check, do not give warning if the analyzed conversion
10914 -- has an expression with non-static bounds, and the bounds of the
10915 -- target are static. This avoids junk warnings in cases where the
10916 -- conversion is necessary to establish staticness, for example in
10917 -- a case statement.
10918
10919 if not Is_OK_Static_Subtype (Operand_Typ)
10920 and then Is_OK_Static_Subtype (Target_Typ)
10921 then
10922 null;
10923
5cc9353d
RD		 10924 -- Finally, if this type conversion occurs in a context requiring
10925 -- a prefix, and the expression is a qualified expression then the
10926 -- type conversion is not redundant, since a qualified expression
10927 -- is not a prefix, whereas a type conversion is. For example, "X
10928 -- := T'(Funx(...)).Y;" is illegal because a selected component
10929 -- requires a prefix, but a type conversion makes it legal: "X :=
10930 -- T(T'(Funx(...))).Y;"
4adf3c50 10931
9db0b232
AC		 10932 -- In Ada 2012, a qualified expression is a name, so this idiom is
10933 -- no longer needed, but we still suppress the warning because it
10934 -- seems unfriendly for warnings to pop up when you switch to the
10935 -- newer language version.
be257e99
AC		 10936
10937 elsif Nkind (Orig_N) = N_Qualified_Expression
f5d96d00
AC		 10938 and then Nkind_In (Parent (N), N_Attribute_Reference,
10939 N_Indexed_Component,
10940 N_Selected_Component,
10941 N_Slice,
10942 N_Explicit_Dereference)
be257e99
AC		 10943 then
10944 null;
10945
2352eadb
AC		 10946 -- Never warn on conversion to Long_Long_Integer'Base since
10947 -- that is most likely an artifact of the extended overflow
10948 -- checking and comes from complex expanded code.
10949
10950 elsif Orig_T = Base_Type (Standard_Long_Long_Integer) then
10951 null;
10952
ae2aa109
AC		 10953 -- Here we give the redundant conversion warning. If it is an
10954 -- entity, give the name of the entity in the message. If not,
10955 -- just mention the expression.
4b2d2c13 10956
324ac540
AC		 10957 -- Shoudn't we test Warn_On_Redundant_Constructs here ???
10958
4b2d2c13 10959 else
ae2aa109
AC		 10960 if Is_Entity_Name (Orig_N) then
10961 Error_Msg_Node_2 := Orig_T;
10962 Error_Msg_NE -- CODEFIX
324ac540 10963 ("??redundant conversion, & is of type &!",
ae2aa109
AC		 10964 N, Entity (Orig_N));
10965 else
10966 Error_Msg_NE
324ac540 10967 ("??redundant conversion, expression is of type&!",
ae2aa109
AC		 10968 N, Orig_T);
10969 end if;
4b2d2c13 10970 end if;
fbf5a39b 10971 end if;
996ae0b0 10972 end if;
758c442c 10973
b7d1f17f 10974 -- Ada 2005 (AI-251): Handle class-wide interface type conversions.
0669bebe
GB		 10975 -- No need to perform any interface conversion if the type of the
10976 -- expression coincides with the target type.
758c442c 10977
0791fbe9 10978 if Ada_Version >= Ada_2005
4460a9bc 10979 and then Expander_Active
b7d1f17f 10980 and then Operand_Typ /= Target_Typ
0669bebe 10981 then
b7d1f17f
HK		 10982 declare
10983 Opnd : Entity_Id := Operand_Typ;
10984 Target : Entity_Id := Target_Typ;
758c442c 10985
b7d1f17f 10986 begin
e4dc3327
AC		 10987 -- If the type of the operand is a limited view, use nonlimited
10988 -- view when available. If it is a class-wide type, recover the
10989 -- class-wide type of the nonlimited view.
414c6563 10990
47346923
AC		 10991 if From_Limited_With (Opnd)
10992 and then Has_Non_Limited_View (Opnd)
10993 then
10994 Opnd := Non_Limited_View (Opnd);
10995 Set_Etype (Expression (N), Opnd);
414c6563
AC		 10996 end if;
10997
b7d1f17f 10998 if Is_Access_Type (Opnd) then
841dd0f5 10999 Opnd := Designated_Type (Opnd);
1420b484
JM		 11000 end if;
11001
b7d1f17f 11002 if Is_Access_Type (Target_Typ) then
841dd0f5 11003 Target := Designated_Type (Target);
4197ae1e 11004 end if;
c8ef728f 11005
b7d1f17f
HK		 11006 if Opnd = Target then
11007 null;
c8ef728f 11008
b7d1f17f 11009 -- Conversion from interface type
ea985d95 11010
b7d1f17f 11011 elsif Is_Interface (Opnd) then
ea985d95 11012
b7d1f17f 11013 -- Ada 2005 (AI-217): Handle entities from limited views
aa180613 11014
7b56a91b 11015 if From_Limited_With (Opnd) then
b7d1f17f 11016 Error_Msg_Qual_Level := 99;
305caf42
AC		 11017 Error_Msg_NE -- CODEFIX
11018 ("missing WITH clause on package &", N,
b7d1f17f
HK		 11019 Cunit_Entity (Get_Source_Unit (Base_Type (Opnd))));
11020 Error_Msg_N
11021 ("type conversions require visibility of the full view",
11022 N);
aa180613 11023
7b56a91b 11024 elsif From_Limited_With (Target)
aa5147f0
ES		 11025 and then not
11026 (Is_Access_Type (Target_Typ)
11027 and then Present (Non_Limited_View (Etype (Target))))
11028 then
b7d1f17f 11029 Error_Msg_Qual_Level := 99;
305caf42
AC		 11030 Error_Msg_NE -- CODEFIX
11031 ("missing WITH clause on package &", N,
b7d1f17f
HK		 11032 Cunit_Entity (Get_Source_Unit (Base_Type (Target))));
11033 Error_Msg_N
11034 ("type conversions require visibility of the full view",
11035 N);
aa180613 11036
b7d1f17f 11037 else
f6f4d8d4 11038 Expand_Interface_Conversion (N);
b7d1f17f
HK		 11039 end if;
11040
11041 -- Conversion to interface type
11042
11043 elsif Is_Interface (Target) then
11044
11045 -- Handle subtypes
11046
8a95f4e8 11047 if Ekind_In (Opnd, E_Protected_Subtype, E_Task_Subtype) then
b7d1f17f
HK		 11048 Opnd := Etype (Opnd);
11049 end if;
11050
f6f4d8d4
JM		 11051 if Is_Class_Wide_Type (Opnd)
11052 or else Interface_Present_In_Ancestor
11053 (Typ => Opnd,
11054 Iface => Target)
b7d1f17f 11055 then
b7d1f17f 11056 Expand_Interface_Conversion (N);
f6f4d8d4
JM		 11057 else
11058 Error_Msg_Name_1 := Chars (Etype (Target));
11059 Error_Msg_Name_2 := Chars (Opnd);
11060 Error_Msg_N
11061 ("wrong interface conversion (% is not a progenitor "
11062 & "of %)", N);
b7d1f17f
HK		 11063 end if;
11064 end if;
11065 end;
758c442c 11066 end if;
804fc056 11067
6cbfce7e
AC		 11068 -- Ada 2012: once the type conversion is resolved, check whether the
11069 -- operand statisfies the static predicate of the target type.
804fc056
AC		 11070
11071 if Has_Predicates (Target_Typ) then
6cbfce7e 11072 Check_Expression_Against_Static_Predicate (N, Target_Typ);
804fc056 11073 end if;
98bf4cf4 11074
d8ee014f
YM		 11075 -- If at this stage we have a real to integer conversion, make sure that
11076 -- the Do_Range_Check flag is set, because such conversions in general
b0cd50fd
AC		 11077 -- need a range check. We only need this if expansion is off.
11078 -- In GNATprove mode, we only do that when converting from fixed-point
d8ee014f
YM		 11079 -- (as floating-point to integer conversions are now handled in
11080 -- GNATprove mode).
98bf4cf4
AC		 11081
11082 if Nkind (N) = N_Type_Conversion
d8ee014f 11083 and then not Expander_Active
98bf4cf4 11084 and then Is_Integer_Type (Target_Typ)
b0cd50fd
AC		 11085 and then (Is_Fixed_Point_Type (Operand_Typ)
11086 or else (not GNATprove_Mode
11087 and then Is_Floating_Point_Type (Operand_Typ)))
98bf4cf4
AC		 11088 then
11089 Set_Do_Range_Check (Operand);
11090 end if;
6905a049
AC		 11091
11092 -- Generating C code a type conversion of an access to constrained
11093 -- array type to access to unconstrained array type involves building
11094 -- a fat pointer which in general cannot be generated on the fly. We
11095 -- remove side effects in order to store the result of the conversion
11096 -- into a temporary.
11097
c63a2ad6 11098 if Modify_Tree_For_C
6905a049
AC		 11099 and then Nkind (N) = N_Type_Conversion
11100 and then Nkind (Parent (N)) /= N_Object_Declaration
11101 and then Is_Access_Type (Etype (N))
11102 and then Is_Array_Type (Designated_Type (Etype (N)))
11103 and then not Is_Constrained (Designated_Type (Etype (N)))
11104 and then Is_Constrained (Designated_Type (Etype (Expression (N))))
11105 then
11106 Remove_Side_Effects (N);
11107 end if;
996ae0b0
RK		 11108 end Resolve_Type_Conversion;
11109
11110 ----------------------
11111 -- Resolve_Unary_Op --
11112 ----------------------
11113
11114 procedure Resolve_Unary_Op (N : Node_Id; Typ : Entity_Id) is
fbf5a39b
AC		 11115 B_Typ : constant Entity_Id := Base_Type (Typ);
11116 R : constant Node_Id := Right_Opnd (N);
11117 OK : Boolean;
11118 Lo : Uint;
11119 Hi : Uint;
996ae0b0
RK		 11120
11121 begin
7a489a2b
AC		 11122 if Is_Modular_Integer_Type (Typ) and then Nkind (N) /= N_Op_Not then
11123 Error_Msg_Name_1 := Chars (Typ);
ce5ba43a 11124 Check_SPARK_05_Restriction
7a489a2b
AC		 11125 ("unary operator not defined for modular type%", N);
11126 end if;
11127
b7d1f17f 11128 -- Deal with intrinsic unary operators
996ae0b0 11129
fbf5a39b
AC		 11130 if Comes_From_Source (N)
11131 and then Ekind (Entity (N)) = E_Function
11132 and then Is_Imported (Entity (N))
11133 and then Is_Intrinsic_Subprogram (Entity (N))
11134 then
11135 Resolve_Intrinsic_Unary_Operator (N, Typ);
11136 return;
11137 end if;
11138
0669bebe
GB		 11139 -- Deal with universal cases
11140
996ae0b0 11141 if Etype (R) = Universal_Integer
0669bebe
GB		 11142 or else
11143 Etype (R) = Universal_Real
996ae0b0
RK		 11144 then
11145 Check_For_Visible_Operator (N, B_Typ);
11146 end if;
11147
11148 Set_Etype (N, B_Typ);
11149 Resolve (R, B_Typ);
fbf5a39b 11150
9ebe3743
HK		 11151 -- Generate warning for expressions like abs (x mod 2)
11152
11153 if Warn_On_Redundant_Constructs
11154 and then Nkind (N) = N_Op_Abs
11155 then
11156 Determine_Range (Right_Opnd (N), OK, Lo, Hi);
11157
11158 if OK and then Hi >= Lo and then Lo >= 0 then
305caf42 11159 Error_Msg_N -- CODEFIX
324ac540 11160 ("?r?abs applied to known non-negative value has no effect", N);
9ebe3743
HK		 11161 end if;
11162 end if;
11163
0669bebe
GB		 11164 -- Deal with reference generation
11165
996ae0b0 11166 Check_Unset_Reference (R);
fbf5a39b 11167 Generate_Operator_Reference (N, B_Typ);
dec6faf1 11168 Analyze_Dimension (N);
996ae0b0
RK		 11169 Eval_Unary_Op (N);
11170
11171 -- Set overflow checking bit. Much cleverer code needed here eventually
11172 -- and perhaps the Resolve routines should be separated for the various
11173 -- arithmetic operations, since they will need different processing ???
11174
11175 if Nkind (N) in N_Op then
11176 if not Overflow_Checks_Suppressed (Etype (N)) then
fbf5a39b 11177 Enable_Overflow_Check (N);
996ae0b0
RK		 11178 end if;
11179 end if;
0669bebe 11180
d81b4bfe
TQ		 11181 -- Generate warning for expressions like -5 mod 3 for integers. No need
11182 -- to worry in the floating-point case, since parens do not affect the
11183 -- result so there is no point in giving in a warning.
0669bebe
GB		 11184
11185 declare
11186 Norig : constant Node_Id := Original_Node (N);
11187 Rorig : Node_Id;
11188 Val : Uint;
11189 HB : Uint;
11190 LB : Uint;
11191 Lval : Uint;
11192 Opnd : Node_Id;
11193
11194 begin
11195 if Warn_On_Questionable_Missing_Parens
11196 and then Comes_From_Source (Norig)
11197 and then Is_Integer_Type (Typ)
11198 and then Nkind (Norig) = N_Op_Minus
11199 then
11200 Rorig := Original_Node (Right_Opnd (Norig));
11201
11202 -- We are looking for cases where the right operand is not
f3d57416 11203 -- parenthesized, and is a binary operator, multiply, divide, or
0669bebe
GB		 11204 -- mod. These are the cases where the grouping can affect results.
11205
11206 if Paren_Count (Rorig) = 0
45fc7ddb 11207 and then Nkind_In (Rorig, N_Op_Mod, N_Op_Multiply, N_Op_Divide)
0669bebe
GB		 11208 then
11209 -- For mod, we always give the warning, since the value is
11210 -- affected by the parenthesization (e.g. (-5) mod 315 /=
d81b4bfe 11211 -- -(5 mod 315)). But for the other cases, the only concern is
0669bebe
GB		 11212 -- overflow, e.g. for the case of 8 big signed (-(2 * 64)
11213 -- overflows, but (-2) * 64 does not). So we try to give the
11214 -- message only when overflow is possible.
11215
11216 if Nkind (Rorig) /= N_Op_Mod
11217 and then Compile_Time_Known_Value (R)
11218 then
11219 Val := Expr_Value (R);
11220
11221 if Compile_Time_Known_Value (Type_High_Bound (Typ)) then
11222 HB := Expr_Value (Type_High_Bound (Typ));
11223 else
11224 HB := Expr_Value (Type_High_Bound (Base_Type (Typ)));
11225 end if;
11226
11227 if Compile_Time_Known_Value (Type_Low_Bound (Typ)) then
11228 LB := Expr_Value (Type_Low_Bound (Typ));
11229 else
11230 LB := Expr_Value (Type_Low_Bound (Base_Type (Typ)));
11231 end if;
11232
d81b4bfe
TQ		 11233 -- Note that the test below is deliberately excluding the
11234 -- largest negative number, since that is a potentially
0669bebe
GB		 11235 -- troublesome case (e.g. -2 * x, where the result is the
11236 -- largest negative integer has an overflow with 2 * x).
11237
11238 if Val > LB and then Val <= HB then
11239 return;
11240 end if;
11241 end if;
11242
11243 -- For the multiplication case, the only case we have to worry
11244 -- about is when (-a)*b is exactly the largest negative number
11245 -- so that -(a*b) can cause overflow. This can only happen if
11246 -- a is a power of 2, and more generally if any operand is a
11247 -- constant that is not a power of 2, then the parentheses
11248 -- cannot affect whether overflow occurs. We only bother to
11249 -- test the left most operand
11250
11251 -- Loop looking at left operands for one that has known value
11252
11253 Opnd := Rorig;
11254 Opnd_Loop : while Nkind (Opnd) = N_Op_Multiply loop
11255 if Compile_Time_Known_Value (Left_Opnd (Opnd)) then
11256 Lval := UI_Abs (Expr_Value (Left_Opnd (Opnd)));
11257
11258 -- Operand value of 0 or 1 skips warning
11259
11260 if Lval <= 1 then
11261 return;
11262
11263 -- Otherwise check power of 2, if power of 2, warn, if
11264 -- anything else, skip warning.
11265
11266 else
11267 while Lval /= 2 loop
11268 if Lval mod 2 = 1 then
11269 return;
11270 else
11271 Lval := Lval / 2;
11272 end if;
11273 end loop;
11274
11275 exit Opnd_Loop;
11276 end if;
11277 end if;
11278
11279 -- Keep looking at left operands
11280
11281 Opnd := Left_Opnd (Opnd);
11282 end loop Opnd_Loop;
11283
11284 -- For rem or "/" we can only have a problematic situation
11285 -- if the divisor has a value of minus one or one. Otherwise
11286 -- overflow is impossible (divisor > 1) or we have a case of
11287 -- division by zero in any case.
11288
45fc7ddb 11289 if Nkind_In (Rorig, N_Op_Divide, N_Op_Rem)
0669bebe
GB		 11290 and then Compile_Time_Known_Value (Right_Opnd (Rorig))
11291 and then UI_Abs (Expr_Value (Right_Opnd (Rorig))) /= 1
11292 then
11293 return;
11294 end if;
11295
11296 -- If we fall through warning should be issued
11297
324ac540
AC		 11298 -- Shouldn't we test Warn_On_Questionable_Missing_Parens ???
11299
ed2233dc 11300 Error_Msg_N
324ac540 11301 ("??unary minus expression should be parenthesized here!", N);
0669bebe
GB		 11302 end if;
11303 end if;
11304 end;
996ae0b0
RK		 11305 end Resolve_Unary_Op;
11306
11307 ----------------------------------
11308 -- Resolve_Unchecked_Expression --
11309 ----------------------------------
11310
11311 procedure Resolve_Unchecked_Expression
11312 (N : Node_Id;
11313 Typ : Entity_Id)
11314 is
11315 begin
11316 Resolve (Expression (N), Typ, Suppress => All_Checks);
11317 Set_Etype (N, Typ);
11318 end Resolve_Unchecked_Expression;
11319
11320 ---------------------------------------
11321 -- Resolve_Unchecked_Type_Conversion --
11322 ---------------------------------------
11323
11324 procedure Resolve_Unchecked_Type_Conversion
11325 (N : Node_Id;
11326 Typ : Entity_Id)
11327 is
07fc65c4
GB		 11328 pragma Warnings (Off, Typ);
11329
996ae0b0
RK		 11330 Operand : constant Node_Id := Expression (N);
11331 Opnd_Type : constant Entity_Id := Etype (Operand);
11332
11333 begin
a77842bd 11334 -- Resolve operand using its own type
996ae0b0
RK		 11335
11336 Resolve (Operand, Opnd_Type);
36428cc4
AC		 11337
11338 -- In an inlined context, the unchecked conversion may be applied
11339 -- to a literal, in which case its type is the type of the context.
11340 -- (In other contexts conversions cannot apply to literals).
11341
11342 if In_Inlined_Body
480156b2
AC		 11343 and then (Opnd_Type = Any_Character or else
11344 Opnd_Type = Any_Integer or else
11345 Opnd_Type = Any_Real)
36428cc4
AC		 11346 then
11347 Set_Etype (Operand, Typ);
11348 end if;
11349
dec6faf1 11350 Analyze_Dimension (N);
996ae0b0 11351 Eval_Unchecked_Conversion (N);
996ae0b0
RK		 11352 end Resolve_Unchecked_Type_Conversion;
11353
11354 ------------------------------
11355 -- Rewrite_Operator_As_Call --
11356 ------------------------------
11357
11358 procedure Rewrite_Operator_As_Call (N : Node_Id; Nam : Entity_Id) is
fbf5a39b
AC		 11359 Loc : constant Source_Ptr := Sloc (N);
11360 Actuals : constant List_Id := New_List;
996ae0b0
RK		 11361 New_N : Node_Id;
11362
11363 begin
21d7ef70 11364 if Nkind (N) in N_Binary_Op then
996ae0b0
RK		 11365 Append (Left_Opnd (N), Actuals);
11366 end if;
11367
11368 Append (Right_Opnd (N), Actuals);
11369
11370 New_N :=
11371 Make_Function_Call (Sloc => Loc,
11372 Name => New_Occurrence_Of (Nam, Loc),
11373 Parameter_Associations => Actuals);
11374
11375 Preserve_Comes_From_Source (New_N, N);
11376 Preserve_Comes_From_Source (Name (New_N), N);
11377 Rewrite (N, New_N);
11378 Set_Etype (N, Etype (Nam));
11379 end Rewrite_Operator_As_Call;
11380
11381 ------------------------------
11382 -- Rewrite_Renamed_Operator --
11383 ------------------------------
11384
0ab80019
AC		 11385 procedure Rewrite_Renamed_Operator
11386 (N : Node_Id;
11387 Op : Entity_Id;
11388 Typ : Entity_Id)
11389 is
996ae0b0
RK		 11390 Nam : constant Name_Id := Chars (Op);
11391 Is_Binary : constant Boolean := Nkind (N) in N_Binary_Op;
11392 Op_Node : Node_Id;
11393
11394 begin
8d81fb4e
AC		 11395 -- Do not perform this transformation within a pre/postcondition,
11396 -- because the expression will be re-analyzed, and the transformation
11397 -- might affect the visibility of the operator, e.g. in an instance.
d566e90a
HK		 11398 -- Note that fully analyzed and expanded pre/postconditions appear as
11399 -- pragma Check equivalents.
8d81fb4e 11400
d566e90a 11401 if In_Pre_Post_Condition (N) then
8d81fb4e
AC		 11402 return;
11403 end if;
11404
d81b4bfe
TQ		 11405 -- Rewrite the operator node using the real operator, not its renaming.
11406 -- Exclude user-defined intrinsic operations of the same name, which are
11407 -- treated separately and rewritten as calls.
996ae0b0 11408
964f13da 11409 if Ekind (Op) /= E_Function or else Chars (N) /= Nam then
996ae0b0
RK		 11410 Op_Node := New_Node (Operator_Kind (Nam, Is_Binary), Sloc (N));
11411 Set_Chars (Op_Node, Nam);
11412 Set_Etype (Op_Node, Etype (N));
11413 Set_Entity (Op_Node, Op);
11414 Set_Right_Opnd (Op_Node, Right_Opnd (N));
11415
b7d1f17f
HK		 11416 -- Indicate that both the original entity and its renaming are
11417 -- referenced at this point.
fbf5a39b
AC		 11418
11419 Generate_Reference (Entity (N), N);
996ae0b0
RK		 11420 Generate_Reference (Op, N);
11421
11422 if Is_Binary then
d566e90a 11423 Set_Left_Opnd (Op_Node, Left_Opnd (N));
996ae0b0
RK		 11424 end if;
11425
11426 Rewrite (N, Op_Node);
0ab80019 11427
1366997b
AC		 11428 -- If the context type is private, add the appropriate conversions so
11429 -- that the operator is applied to the full view. This is done in the
11430 -- routines that resolve intrinsic operators.
0ab80019 11431
d566e90a 11432 if Is_Intrinsic_Subprogram (Op) and then Is_Private_Type (Typ) then
0ab80019 11433 case Nkind (N) is
d8f43ee6
HK		 11434 when N_Op_Add
11435 | N_Op_Divide
11436 | N_Op_Expon
11437 | N_Op_Mod
11438 | N_Op_Multiply
11439 | N_Op_Rem
11440 | N_Op_Subtract
11441 =>
0ab80019
AC		 11442 Resolve_Intrinsic_Operator (N, Typ);
11443
d8f43ee6
HK		 11444 when N_Op_Abs
11445 | N_Op_Minus
11446 | N_Op_Plus
11447 =>
0ab80019
AC		 11448 Resolve_Intrinsic_Unary_Operator (N, Typ);
11449
11450 when others =>
11451 Resolve (N, Typ);
11452 end case;
11453 end if;
11454
964f13da
RD		 11455 elsif Ekind (Op) = E_Function and then Is_Intrinsic_Subprogram (Op) then
11456
1366997b
AC		 11457 -- Operator renames a user-defined operator of the same name. Use the
11458 -- original operator in the node, which is the one Gigi knows about.
0ab80019
AC		 11459
11460 Set_Entity (N, Op);
11461 Set_Is_Overloaded (N, False);
996ae0b0
RK		 11462 end if;
11463 end Rewrite_Renamed_Operator;
11464
11465 -----------------------
11466 -- Set_Slice_Subtype --
11467 -----------------------
11468
1366997b
AC		 11469 -- Build an implicit subtype declaration to represent the type delivered by
11470 -- the slice. This is an abbreviated version of an array subtype. We define
11471 -- an index subtype for the slice, using either the subtype name or the
11472 -- discrete range of the slice. To be consistent with index usage elsewhere
11473 -- we create a list header to hold the single index. This list is not
11474 -- otherwise attached to the syntax tree.
996ae0b0
RK		 11475
11476 procedure Set_Slice_Subtype (N : Node_Id) is
11477 Loc : constant Source_Ptr := Sloc (N);
fbf5a39b 11478 Index_List : constant List_Id := New_List;
996ae0b0 11479 Index : Node_Id;
996ae0b0
RK		 11480 Index_Subtype : Entity_Id;
11481 Index_Type : Entity_Id;
11482 Slice_Subtype : Entity_Id;
11483 Drange : constant Node_Id := Discrete_Range (N);
11484
11485 begin
08cd7c2f
AC		 11486 Index_Type := Base_Type (Etype (Drange));
11487
996ae0b0
RK		 11488 if Is_Entity_Name (Drange) then
11489 Index_Subtype := Entity (Drange);
11490
11491 else
11492 -- We force the evaluation of a range. This is definitely needed in
11493 -- the renamed case, and seems safer to do unconditionally. Note in
11494 -- any case that since we will create and insert an Itype referring
11495 -- to this range, we must make sure any side effect removal actions
11496 -- are inserted before the Itype definition.
11497
11498 if Nkind (Drange) = N_Range then
11499 Force_Evaluation (Low_Bound (Drange));
11500 Force_Evaluation (High_Bound (Drange));
996ae0b0 11501
08cd7c2f
AC		 11502 -- If the discrete range is given by a subtype indication, the
11503 -- type of the slice is the base of the subtype mark.
11504
11505 elsif Nkind (Drange) = N_Subtype_Indication then
11506 declare
11507 R : constant Node_Id := Range_Expression (Constraint (Drange));
11508 begin
11509 Index_Type := Base_Type (Entity (Subtype_Mark (Drange)));
11510 Force_Evaluation (Low_Bound (R));
11511 Force_Evaluation (High_Bound (R));
11512 end;
11513 end if;
996ae0b0
RK		 11514
11515 Index_Subtype := Create_Itype (Subtype_Kind (Ekind (Index_Type)), N);
11516
8a95f4e8 11517 -- Take a new copy of Drange (where bounds have been rewritten to
3c1ecd7e
AC		 11518 -- reference side-effect-free names). Using a separate tree ensures
11519 -- that further expansion (e.g. while rewriting a slice assignment
8a95f4e8
RD		 11520 -- into a FOR loop) does not attempt to remove side effects on the
11521 -- bounds again (which would cause the bounds in the index subtype
11522 -- definition to refer to temporaries before they are defined) (the
11523 -- reason is that some names are considered side effect free here
11524 -- for the subtype, but not in the context of a loop iteration
11525 -- scheme).
11526
11527 Set_Scalar_Range (Index_Subtype, New_Copy_Tree (Drange));
4230bdb7 11528 Set_Parent (Scalar_Range (Index_Subtype), Index_Subtype);
996ae0b0
RK		 11529 Set_Etype (Index_Subtype, Index_Type);
11530 Set_Size_Info (Index_Subtype, Index_Type);
11531 Set_RM_Size (Index_Subtype, RM_Size (Index_Type));
11532 end if;
11533
11534 Slice_Subtype := Create_Itype (E_Array_Subtype, N);
11535
11536 Index := New_Occurrence_Of (Index_Subtype, Loc);
11537 Set_Etype (Index, Index_Subtype);
11538 Append (Index, Index_List);
11539
996ae0b0
RK		 11540 Set_First_Index (Slice_Subtype, Index);
11541 Set_Etype (Slice_Subtype, Base_Type (Etype (N)));
11542 Set_Is_Constrained (Slice_Subtype, True);
996ae0b0 11543
8a95f4e8
RD		 11544 Check_Compile_Time_Size (Slice_Subtype);
11545
b7d1f17f
HK		 11546 -- The Etype of the existing Slice node is reset to this slice subtype.
11547 -- Its bounds are obtained from its first index.
996ae0b0
RK		 11548
11549 Set_Etype (N, Slice_Subtype);
11550
7738270b
AC		 11551 -- For bit-packed slice subtypes, freeze immediately (except in the case
11552 -- of being in a "spec expression" where we never freeze when we first
11553 -- see the expression).
8a95f4e8 11554
7738270b 11555 if Is_Bit_Packed_Array (Slice_Subtype) and not In_Spec_Expression then
8a95f4e8 11556 Freeze_Itype (Slice_Subtype, N);
996ae0b0 11557
cfab0c49
AC		 11558 -- For all other cases insert an itype reference in the slice's actions
11559 -- so that the itype is frozen at the proper place in the tree (i.e. at
11560 -- the point where actions for the slice are analyzed). Note that this
11561 -- is different from freezing the itype immediately, which might be
6ff6152d
ES		 11562 -- premature (e.g. if the slice is within a transient scope). This needs
11563 -- to be done only if expansion is enabled.
cfab0c49 11564
4460a9bc 11565 elsif Expander_Active then
8a95f4e8
RD		 11566 Ensure_Defined (Typ => Slice_Subtype, N => N);
11567 end if;
996ae0b0
RK		 11568 end Set_Slice_Subtype;
11569
11570 --------------------------------
11571 -- Set_String_Literal_Subtype --
11572 --------------------------------
11573
11574 procedure Set_String_Literal_Subtype (N : Node_Id; Typ : Entity_Id) is
c8ef728f
ES		 11575 Loc : constant Source_Ptr := Sloc (N);
11576 Low_Bound : constant Node_Id :=
d81b4bfe 11577 Type_Low_Bound (Etype (First_Index (Typ)));
996ae0b0
RK		 11578 Subtype_Id : Entity_Id;
11579
11580 begin
11581 if Nkind (N) /= N_String_Literal then
11582 return;
996ae0b0
RK		 11583 end if;
11584
c8ef728f 11585 Subtype_Id := Create_Itype (E_String_Literal_Subtype, N);
91b1417d
AC		 11586 Set_String_Literal_Length (Subtype_Id, UI_From_Int
11587 (String_Length (Strval (N))));
c8ef728f
ES		 11588 Set_Etype (Subtype_Id, Base_Type (Typ));
11589 Set_Is_Constrained (Subtype_Id);
11590 Set_Etype (N, Subtype_Id);
11591
1366997b
AC		 11592 -- The low bound is set from the low bound of the corresponding index
11593 -- type. Note that we do not store the high bound in the string literal
11594 -- subtype, but it can be deduced if necessary from the length and the
11595 -- low bound.
996ae0b0 11596
5f44f0d4 11597 if Is_OK_Static_Expression (Low_Bound) then
c8ef728f 11598 Set_String_Literal_Low_Bound (Subtype_Id, Low_Bound);
996ae0b0 11599
5f44f0d4
AC		 11600 -- If the lower bound is not static we create a range for the string
11601 -- literal, using the index type and the known length of the literal.
11602 -- The index type is not necessarily Positive, so the upper bound is
11603 -- computed as T'Val (T'Pos (Low_Bound) + L - 1).
c8ef728f 11604
5f44f0d4 11605 else
c8ef728f 11606 declare
5f44f0d4
AC		 11607 Index_List : constant List_Id := New_List;
11608 Index_Type : constant Entity_Id := Etype (First_Index (Typ));
11609 High_Bound : constant Node_Id :=
53f29d4f
AC		 11610 Make_Attribute_Reference (Loc,
11611 Attribute_Name => Name_Val,
11612 Prefix =>
11613 New_Occurrence_Of (Index_Type, Loc),
11614 Expressions => New_List (
11615 Make_Op_Add (Loc,
11616 Left_Opnd =>
11617 Make_Attribute_Reference (Loc,
11618 Attribute_Name => Name_Pos,
11619 Prefix =>
11620 New_Occurrence_Of (Index_Type, Loc),
11621 Expressions =>
11622 New_List (New_Copy_Tree (Low_Bound))),
11623 Right_Opnd =>
11624 Make_Integer_Literal (Loc,
11625 String_Length (Strval (N)) - 1))));
c0b11850 11626
c8ef728f 11627 Array_Subtype : Entity_Id;
c8ef728f
ES		 11628 Drange : Node_Id;
11629 Index : Node_Id;
5f44f0d4 11630 Index_Subtype : Entity_Id;
c8ef728f
ES		 11631
11632 begin
56e94186
AC		 11633 if Is_Integer_Type (Index_Type) then
11634 Set_String_Literal_Low_Bound
11635 (Subtype_Id, Make_Integer_Literal (Loc, 1));
11636
11637 else
11638 -- If the index type is an enumeration type, build bounds
11639 -- expression with attributes.
11640
11641 Set_String_Literal_Low_Bound
11642 (Subtype_Id,
11643 Make_Attribute_Reference (Loc,
11644 Attribute_Name => Name_First,
11645 Prefix =>
11646 New_Occurrence_Of (Base_Type (Index_Type), Loc)));
11647 Set_Etype (String_Literal_Low_Bound (Subtype_Id), Index_Type);
11648 end if;
11649
c0b11850
AC		 11650 Analyze_And_Resolve (String_Literal_Low_Bound (Subtype_Id));
11651
11652 -- Build bona fide subtype for the string, and wrap it in an
11653 -- unchecked conversion, because the backend expects the
11654 -- String_Literal_Subtype to have a static lower bound.
11655
c8ef728f
ES		 11656 Index_Subtype :=
11657 Create_Itype (Subtype_Kind (Ekind (Index_Type)), N);
0669bebe 11658 Drange := Make_Range (Loc, New_Copy_Tree (Low_Bound), High_Bound);
c8ef728f
ES		 11659 Set_Scalar_Range (Index_Subtype, Drange);
11660 Set_Parent (Drange, N);
11661 Analyze_And_Resolve (Drange, Index_Type);
11662
36fcf362
RD		 11663 -- In the context, the Index_Type may already have a constraint,
11664 -- so use common base type on string subtype. The base type may
11665 -- be used when generating attributes of the string, for example
11666 -- in the context of a slice assignment.
11667
4adf3c50
AC		 11668 Set_Etype (Index_Subtype, Base_Type (Index_Type));
11669 Set_Size_Info (Index_Subtype, Index_Type);
11670 Set_RM_Size (Index_Subtype, RM_Size (Index_Type));
c8ef728f
ES		 11671
11672 Array_Subtype := Create_Itype (E_Array_Subtype, N);
11673
11674 Index := New_Occurrence_Of (Index_Subtype, Loc);
11675 Set_Etype (Index, Index_Subtype);
11676 Append (Index, Index_List);
11677
11678 Set_First_Index (Array_Subtype, Index);
11679 Set_Etype (Array_Subtype, Base_Type (Typ));
11680 Set_Is_Constrained (Array_Subtype, True);
c8ef728f
ES		 11681
11682 Rewrite (N,
11683 Make_Unchecked_Type_Conversion (Loc,
11684 Subtype_Mark => New_Occurrence_Of (Array_Subtype, Loc),
5f44f0d4 11685 Expression => Relocate_Node (N)));
c8ef728f
ES		 11686 Set_Etype (N, Array_Subtype);
11687 end;
11688 end if;
996ae0b0
RK		 11689 end Set_String_Literal_Subtype;
11690
0669bebe
GB		 11691 ------------------------------
11692 -- Simplify_Type_Conversion --
11693 ------------------------------
11694
11695 procedure Simplify_Type_Conversion (N : Node_Id) is
11696 begin
11697 if Nkind (N) = N_Type_Conversion then
11698 declare
11699 Operand : constant Node_Id := Expression (N);
11700 Target_Typ : constant Entity_Id := Etype (N);
11701 Opnd_Typ : constant Entity_Id := Etype (Operand);
11702
11703 begin
24228312
AC		 11704 -- Special processing if the conversion is the expression of a
11705 -- Rounding or Truncation attribute reference. In this case we
11706 -- replace:
0669bebe 11707
24228312 11708 -- ityp (ftyp'Rounding (x)) or ityp (ftyp'Truncation (x))
0669bebe
GB		 11709
11710 -- by
11711
11712 -- ityp (x)
11713
24228312
AC		 11714 -- with the Float_Truncate flag set to False or True respectively,
11715 -- which is more efficient.
0669bebe 11716
24228312
AC		 11717 if Is_Floating_Point_Type (Opnd_Typ)
11718 and then
11719 (Is_Integer_Type (Target_Typ)
7a5b62b0
AC		 11720 or else (Is_Fixed_Point_Type (Target_Typ)
11721 and then Conversion_OK (N)))
24228312 11722 and then Nkind (Operand) = N_Attribute_Reference
7a5b62b0
AC		 11723 and then Nam_In (Attribute_Name (Operand), Name_Rounding,
11724 Name_Truncation)
0669bebe 11725 then
24228312
AC		 11726 declare
11727 Truncate : constant Boolean :=
7a5b62b0 11728 Attribute_Name (Operand) = Name_Truncation;
24228312
AC		 11729 begin
11730 Rewrite (Operand,
11731 Relocate_Node (First (Expressions (Operand))));
11732 Set_Float_Truncate (N, Truncate);
11733 end;
0669bebe
GB		 11734 end if;
11735 end;
11736 end if;
11737 end Simplify_Type_Conversion;
11738
996ae0b0
RK		 11739 -----------------------------
11740 -- Unique_Fixed_Point_Type --
11741 -----------------------------
11742
11743 function Unique_Fixed_Point_Type (N : Node_Id) return Entity_Id is
cccb761b 11744 procedure Fixed_Point_Error (T1 : Entity_Id; T2 : Entity_Id);
d81b4bfe
TQ		 11745 -- Give error messages for true ambiguity. Messages are posted on node
11746 -- N, and entities T1, T2 are the possible interpretations.
a77842bd
TQ		 11747
11748 -----------------------
11749 -- Fixed_Point_Error --
11750 -----------------------
996ae0b0 11751
cccb761b 11752 procedure Fixed_Point_Error (T1 : Entity_Id; T2 : Entity_Id) is
996ae0b0 11753 begin
ed2233dc
AC		 11754 Error_Msg_N ("ambiguous universal_fixed_expression", N);
11755 Error_Msg_NE ("\\possible interpretation as}", N, T1);
11756 Error_Msg_NE ("\\possible interpretation as}", N, T2);
996ae0b0
RK		 11757 end Fixed_Point_Error;
11758
cccb761b
AC		 11759 -- Local variables
11760
11761 ErrN : Node_Id;
11762 Item : Node_Id;
11763 Scop : Entity_Id;
11764 T1 : Entity_Id;
11765 T2 : Entity_Id;
11766
a77842bd
TQ		 11767 -- Start of processing for Unique_Fixed_Point_Type
11768
996ae0b0
RK		 11769 begin
11770 -- The operations on Duration are visible, so Duration is always a
11771 -- possible interpretation.
11772
11773 T1 := Standard_Duration;
11774
bc5f3720 11775 -- Look for fixed-point types in enclosing scopes
996ae0b0 11776
fbf5a39b 11777 Scop := Current_Scope;
996ae0b0
RK		 11778 while Scop /= Standard_Standard loop
11779 T2 := First_Entity (Scop);
996ae0b0
RK		 11780 while Present (T2) loop
11781 if Is_Fixed_Point_Type (T2)
11782 and then Current_Entity (T2) = T2
11783 and then Scope (Base_Type (T2)) = Scop
11784 then
11785 if Present (T1) then
cccb761b 11786 Fixed_Point_Error (T1, T2);
996ae0b0
RK		 11787 return Any_Type;
11788 else
11789 T1 := T2;
11790 end if;
11791 end if;
11792
11793 Next_Entity (T2);
11794 end loop;
11795
11796 Scop := Scope (Scop);
11797 end loop;
11798
a77842bd 11799 -- Look for visible fixed type declarations in the context
996ae0b0
RK		 11800
11801 Item := First (Context_Items (Cunit (Current_Sem_Unit)));
996ae0b0 11802 while Present (Item) loop
996ae0b0
RK		 11803 if Nkind (Item) = N_With_Clause then
11804 Scop := Entity (Name (Item));
11805 T2 := First_Entity (Scop);
996ae0b0
RK		 11806 while Present (T2) loop
11807 if Is_Fixed_Point_Type (T2)
11808 and then Scope (Base_Type (T2)) = Scop
19fb051c 11809 and then (Is_Potentially_Use_Visible (T2) or else In_Use (T2))
996ae0b0
RK		 11810 then
11811 if Present (T1) then
cccb761b 11812 Fixed_Point_Error (T1, T2);
996ae0b0
RK		 11813 return Any_Type;
11814 else
11815 T1 := T2;
11816 end if;
11817 end if;
11818
11819 Next_Entity (T2);
11820 end loop;
11821 end if;
11822
11823 Next (Item);
11824 end loop;
11825
11826 if Nkind (N) = N_Real_Literal then
cccb761b
AC		 11827 Error_Msg_NE ("??real literal interpreted as }!", N, T1);
11828
996ae0b0 11829 else
cccb761b
AC		 11830 -- When the context is a type conversion, issue the warning on the
11831 -- expression of the conversion because it is the actual operation.
11832
11833 if Nkind_In (N, N_Type_Conversion, N_Unchecked_Type_Conversion) then
11834 ErrN := Expression (N);
11835 else
11836 ErrN := N;
11837 end if;
11838
324ac540 11839 Error_Msg_NE
cccb761b 11840 ("??universal_fixed expression interpreted as }!", ErrN, T1);
996ae0b0
RK		 11841 end if;
11842
11843 return T1;
11844 end Unique_Fixed_Point_Type;
11845
11846 ----------------------
11847 -- Valid_Conversion --
11848 ----------------------
11849
11850 function Valid_Conversion
6cce2156
GD		 11851 (N : Node_Id;
11852 Target : Entity_Id;
11853 Operand : Node_Id;
11854 Report_Errs : Boolean := True) return Boolean
996ae0b0 11855 is
e6425869
AC		 11856 Target_Type : constant Entity_Id := Base_Type (Target);
11857 Opnd_Type : Entity_Id := Etype (Operand);
11858 Inc_Ancestor : Entity_Id;
996ae0b0
RK		 11859
11860 function Conversion_Check
11861 (Valid : Boolean;
0ab80019 11862 Msg : String) return Boolean;
996ae0b0
RK		 11863 -- Little routine to post Msg if Valid is False, returns Valid value
11864
1486a00e 11865 procedure Conversion_Error_N (Msg : String; N : Node_Or_Entity_Id);
6cce2156
GD		 11866 -- If Report_Errs, then calls Errout.Error_Msg_N with its arguments
11867
1486a00e 11868 procedure Conversion_Error_NE
6cce2156
GD		 11869 (Msg : String;
11870 N : Node_Or_Entity_Id;
11871 E : Node_Or_Entity_Id);
11872 -- If Report_Errs, then calls Errout.Error_Msg_NE with its arguments
11873
996ae0b0
RK		 11874 function Valid_Tagged_Conversion
11875 (Target_Type : Entity_Id;
0ab80019 11876 Opnd_Type : Entity_Id) return Boolean;
996ae0b0
RK		 11877 -- Specifically test for validity of tagged conversions
11878
aa180613 11879 function Valid_Array_Conversion return Boolean;
4adf3c50
AC		 11880 -- Check index and component conformance, and accessibility levels if
11881 -- the component types are anonymous access types (Ada 2005).
aa180613 11882
996ae0b0
RK		 11883 ----------------------
11884 -- Conversion_Check --
11885 ----------------------
11886
11887 function Conversion_Check
11888 (Valid : Boolean;
0ab80019 11889 Msg : String) return Boolean
996ae0b0
RK		 11890 is
11891 begin
0a190dfd
AC		 11892 if not Valid
11893
11894 -- A generic unit has already been analyzed and we have verified
11895 -- that a particular conversion is OK in that context. Since the
11896 -- instance is reanalyzed without relying on the relationships
11897 -- established during the analysis of the generic, it is possible
11898 -- to end up with inconsistent views of private types. Do not emit
11899 -- the error message in such cases. The rest of the machinery in
11900 -- Valid_Conversion still ensures the proper compatibility of
11901 -- target and operand types.
11902
11903 and then not In_Instance
11904 then
1486a00e 11905 Conversion_Error_N (Msg, Operand);
996ae0b0
RK		 11906 end if;
11907
11908 return Valid;
11909 end Conversion_Check;
11910
1486a00e
AC		 11911 ------------------------
11912 -- Conversion_Error_N --
11913 ------------------------
6cce2156 11914
1486a00e 11915 procedure Conversion_Error_N (Msg : String; N : Node_Or_Entity_Id) is
6cce2156
GD		 11916 begin
11917 if Report_Errs then
1486a00e 11918 Error_Msg_N (Msg, N);
6cce2156 11919 end if;
1486a00e 11920 end Conversion_Error_N;
6cce2156 11921
1486a00e
AC		 11922 -------------------------
11923 -- Conversion_Error_NE --
11924 -------------------------
6cce2156 11925
1486a00e 11926 procedure Conversion_Error_NE
6cce2156
GD		 11927 (Msg : String;
11928 N : Node_Or_Entity_Id;
11929 E : Node_Or_Entity_Id)
11930 is
11931 begin
11932 if Report_Errs then
1486a00e 11933 Error_Msg_NE (Msg, N, E);
6cce2156 11934 end if;
1486a00e 11935 end Conversion_Error_NE;
6cce2156 11936
aa180613
RD		 11937 ----------------------------
11938 -- Valid_Array_Conversion --
11939 ----------------------------
11940
5f325af2 11941 function Valid_Array_Conversion return Boolean is
aa180613
RD		 11942 Opnd_Comp_Type : constant Entity_Id := Component_Type (Opnd_Type);
11943 Opnd_Comp_Base : constant Entity_Id := Base_Type (Opnd_Comp_Type);
11944
11945 Opnd_Index : Node_Id;
11946 Opnd_Index_Type : Entity_Id;
11947
11948 Target_Comp_Type : constant Entity_Id :=
11949 Component_Type (Target_Type);
11950 Target_Comp_Base : constant Entity_Id :=
11951 Base_Type (Target_Comp_Type);
11952
11953 Target_Index : Node_Id;
11954 Target_Index_Type : Entity_Id;
11955
11956 begin
11957 -- Error if wrong number of dimensions
11958
11959 if
11960 Number_Dimensions (Target_Type) /= Number_Dimensions (Opnd_Type)
11961 then
1486a00e 11962 Conversion_Error_N
aa180613
RD		 11963 ("incompatible number of dimensions for conversion", Operand);
11964 return False;
11965
11966 -- Number of dimensions matches
11967
11968 else
11969 -- Loop through indexes of the two arrays
11970
11971 Target_Index := First_Index (Target_Type);
11972 Opnd_Index := First_Index (Opnd_Type);
11973 while Present (Target_Index) and then Present (Opnd_Index) loop
11974 Target_Index_Type := Etype (Target_Index);
11975 Opnd_Index_Type := Etype (Opnd_Index);
11976
11977 -- Error if index types are incompatible
11978
11979 if not (Is_Integer_Type (Target_Index_Type)
11980 and then Is_Integer_Type (Opnd_Index_Type))
11981 and then (Root_Type (Target_Index_Type)
11982 /= Root_Type (Opnd_Index_Type))
11983 then
1486a00e 11984 Conversion_Error_N
aa180613
RD		 11985 ("incompatible index types for array conversion",
11986 Operand);
11987 return False;
11988 end if;
11989
11990 Next_Index (Target_Index);
11991 Next_Index (Opnd_Index);
11992 end loop;
11993
11994 -- If component types have same base type, all set
11995
11996 if Target_Comp_Base = Opnd_Comp_Base then
11997 null;
11998
11999 -- Here if base types of components are not the same. The only
12000 -- time this is allowed is if we have anonymous access types.
12001
12002 -- The conversion of arrays of anonymous access types can lead
12003 -- to dangling pointers. AI-392 formalizes the accessibility
12004 -- checks that must be applied to such conversions to prevent
12005 -- out-of-scope references.
12006
19fb051c
AC		 12007 elsif Ekind_In
12008 (Target_Comp_Base, E_Anonymous_Access_Type,
12009 E_Anonymous_Access_Subprogram_Type)
aa180613
RD		 12010 and then Ekind (Opnd_Comp_Base) = Ekind (Target_Comp_Base)
12011 and then
12012 Subtypes_Statically_Match (Target_Comp_Type, Opnd_Comp_Type)
12013 then
12014 if Type_Access_Level (Target_Type) <
83e5da69 12015 Deepest_Type_Access_Level (Opnd_Type)
aa180613
RD		 12016 then
12017 if In_Instance_Body then
43417b90 12018 Error_Msg_Warn := SPARK_Mode /= On;
1486a00e 12019 Conversion_Error_N
4a28b181
AC		 12020 ("source array type has deeper accessibility "
12021 & "level than target<<", Operand);
12022 Conversion_Error_N ("\Program_Error [<<", Operand);
aa180613
RD		 12023 Rewrite (N,
12024 Make_Raise_Program_Error (Sloc (N),
12025 Reason => PE_Accessibility_Check_Failed));
12026 Set_Etype (N, Target_Type);
12027 return False;
12028
12029 -- Conversion not allowed because of accessibility levels
12030
12031 else
1486a00e
AC		 12032 Conversion_Error_N
12033 ("source array type has deeper accessibility "
12034 & "level than target", Operand);
aa180613
RD		 12035 return False;
12036 end if;
19fb051c 12037
aa180613
RD		 12038 else
12039 null;
12040 end if;
12041
12042 -- All other cases where component base types do not match
12043
12044 else
1486a00e 12045 Conversion_Error_N
aa180613
RD		 12046 ("incompatible component types for array conversion",
12047 Operand);
12048 return False;
12049 end if;
12050
45fc7ddb
HK		 12051 -- Check that component subtypes statically match. For numeric
12052 -- types this means that both must be either constrained or
12053 -- unconstrained. For enumeration types the bounds must match.
12054 -- All of this is checked in Subtypes_Statically_Match.
aa180613 12055
45fc7ddb 12056 if not Subtypes_Statically_Match
83e5da69 12057 (Target_Comp_Type, Opnd_Comp_Type)
aa180613 12058 then
1486a00e 12059 Conversion_Error_N
aa180613
RD		 12060 ("component subtypes must statically match", Operand);
12061 return False;
12062 end if;
12063 end if;
12064
12065 return True;
12066 end Valid_Array_Conversion;
12067
996ae0b0
RK		 12068 -----------------------------
12069 -- Valid_Tagged_Conversion --
12070 -----------------------------
12071
12072 function Valid_Tagged_Conversion
12073 (Target_Type : Entity_Id;
0ab80019 12074 Opnd_Type : Entity_Id) return Boolean
996ae0b0
RK		 12075 is
12076 begin
a77842bd 12077 -- Upward conversions are allowed (RM 4.6(22))
996ae0b0
RK		 12078
12079 if Covers (Target_Type, Opnd_Type)
12080 or else Is_Ancestor (Target_Type, Opnd_Type)
12081 then
12082 return True;
12083
a77842bd
TQ		 12084 -- Downward conversion are allowed if the operand is class-wide
12085 -- (RM 4.6(23)).
996ae0b0
RK		 12086
12087 elsif Is_Class_Wide_Type (Opnd_Type)
b7d1f17f 12088 and then Covers (Opnd_Type, Target_Type)
996ae0b0
RK		 12089 then
12090 return True;
12091
12092 elsif Covers (Opnd_Type, Target_Type)
12093 or else Is_Ancestor (Opnd_Type, Target_Type)
12094 then
12095 return
12096 Conversion_Check (False,
12097 "downward conversion of tagged objects not allowed");
758c442c 12098
0669bebe 12099 -- Ada 2005 (AI-251): The conversion to/from interface types is
0310af44 12100 -- always valid. The types involved may be class-wide (sub)types.
758c442c 12101
0310af44
AC		 12102 elsif Is_Interface (Etype (Base_Type (Target_Type)))
12103 or else Is_Interface (Etype (Base_Type (Opnd_Type)))
12104 then
758c442c
GD		 12105 return True;
12106
b7d1f17f 12107 -- If the operand is a class-wide type obtained through a limited_
e4dc3327 12108 -- with clause, and the context includes the nonlimited view, use
b7d1f17f
HK		 12109 -- it to determine whether the conversion is legal.
12110
12111 elsif Is_Class_Wide_Type (Opnd_Type)
7b56a91b 12112 and then From_Limited_With (Opnd_Type)
b7d1f17f
HK		 12113 and then Present (Non_Limited_View (Etype (Opnd_Type)))
12114 and then Is_Interface (Non_Limited_View (Etype (Opnd_Type)))
12115 then
12116 return True;
12117
aa180613
RD		 12118 elsif Is_Access_Type (Opnd_Type)
12119 and then Is_Interface (Directly_Designated_Type (Opnd_Type))
12120 then
12121 return True;
12122
996ae0b0 12123 else
1486a00e 12124 Conversion_Error_NE
996ae0b0
RK		 12125 ("invalid tagged conversion, not compatible with}",
12126 N, First_Subtype (Opnd_Type));
12127 return False;
12128 end if;
12129 end Valid_Tagged_Conversion;
12130
12131 -- Start of processing for Valid_Conversion
12132
12133 begin
12134 Check_Parameterless_Call (Operand);
12135
12136 if Is_Overloaded (Operand) then
12137 declare
12138 I : Interp_Index;
12139 I1 : Interp_Index;
12140 It : Interp;
12141 It1 : Interp;
12142 N1 : Entity_Id;
f0d10385 12143 T1 : Entity_Id;
996ae0b0
RK		 12144
12145 begin
d81b4bfe
TQ		 12146 -- Remove procedure calls, which syntactically cannot appear in
12147 -- this context, but which cannot be removed by type checking,
996ae0b0
RK		 12148 -- because the context does not impose a type.
12149
4adf3c50
AC		 12150 -- The node may be labelled overloaded, but still contain only one
12151 -- interpretation because others were discarded earlier. If this
12152 -- is the case, retain the single interpretation if legal.
9ebe3743 12153
996ae0b0 12154 Get_First_Interp (Operand, I, It);
9ebe3743
HK		 12155 Opnd_Type := It.Typ;
12156 Get_Next_Interp (I, It);
996ae0b0 12157
9ebe3743
HK		 12158 if Present (It.Typ)
12159 and then Opnd_Type /= Standard_Void_Type
12160 then
12161 -- More than one candidate interpretation is available
996ae0b0 12162
9ebe3743
HK		 12163 Get_First_Interp (Operand, I, It);
12164 while Present (It.Typ) loop
12165 if It.Typ = Standard_Void_Type then
12166 Remove_Interp (I);
12167 end if;
1420b484 12168
4d49c6e1
AC		 12169 -- When compiling for a system where Address is of a visible
12170 -- integer type, spurious ambiguities can be produced when
12171 -- arithmetic operations have a literal operand and return
12172 -- System.Address or a descendant of it. These ambiguities
12173 -- are usually resolved by the context, but for conversions
12174 -- there is no context type and the removal of the spurious
12175 -- operations must be done explicitly here.
12176
12177 if not Address_Is_Private
d9d25d04 12178 and then Is_Descendant_Of_Address (It.Typ)
9ebe3743
HK		 12179 then
12180 Remove_Interp (I);
12181 end if;
12182
12183 Get_Next_Interp (I, It);
12184 end loop;
12185 end if;
996ae0b0
RK		 12186
12187 Get_First_Interp (Operand, I, It);
12188 I1 := I;
12189 It1 := It;
12190
12191 if No (It.Typ) then
1486a00e 12192 Conversion_Error_N ("illegal operand in conversion", Operand);
996ae0b0
RK		 12193 return False;
12194 end if;
12195
12196 Get_Next_Interp (I, It);
12197
12198 if Present (It.Typ) then
12199 N1 := It1.Nam;
f0d10385 12200 T1 := It1.Typ;
c8307596 12201 It1 := Disambiguate (Operand, I1, I, Any_Type);
996ae0b0
RK		 12202
12203 if It1 = No_Interp then
1486a00e
AC		 12204 Conversion_Error_N
12205 ("ambiguous operand in conversion", Operand);
996ae0b0 12206
f0d10385
AC		 12207 -- If the interpretation involves a standard operator, use
12208 -- the location of the type, which may be user-defined.
12209
12210 if Sloc (It.Nam) = Standard_Location then
12211 Error_Msg_Sloc := Sloc (It.Typ);
12212 else
12213 Error_Msg_Sloc := Sloc (It.Nam);
12214 end if;
12215
1486a00e 12216 Conversion_Error_N -- CODEFIX
4e7a4f6e 12217 ("\\possible interpretation#!", Operand);
996ae0b0 12218
f0d10385
AC		 12219 if Sloc (N1) = Standard_Location then
12220 Error_Msg_Sloc := Sloc (T1);
12221 else
12222 Error_Msg_Sloc := Sloc (N1);
12223 end if;
12224
1486a00e 12225 Conversion_Error_N -- CODEFIX
4e7a4f6e 12226 ("\\possible interpretation#!", Operand);
996ae0b0
RK		 12227
12228 return False;
12229 end if;
12230 end if;
12231
12232 Set_Etype (Operand, It1.Typ);
12233 Opnd_Type := It1.Typ;
12234 end;
12235 end if;
12236
6fd0a72a
AC		 12237 -- Deal with conversion of integer type to address if the pragma
12238 -- Allow_Integer_Address is in effect. We convert the conversion to
a90bd866 12239 -- an unchecked conversion in this case and we are all done.
6fd0a72a 12240
061828e3 12241 if Address_Integer_Convert_OK (Opnd_Type, Target_Type) then
6fd0a72a
AC		 12242 Rewrite (N, Unchecked_Convert_To (Target_Type, Expression (N)));
12243 Analyze_And_Resolve (N, Target_Type);
12244 return True;
12245 end if;
12246
e6425869
AC		 12247 -- If we are within a child unit, check whether the type of the
12248 -- expression has an ancestor in a parent unit, in which case it
12249 -- belongs to its derivation class even if the ancestor is private.
12250 -- See RM 7.3.1 (5.2/3).
12251
12252 Inc_Ancestor := Get_Incomplete_View_Of_Ancestor (Opnd_Type);
12253
aa180613 12254 -- Numeric types
996ae0b0 12255
6fd0a72a 12256 if Is_Numeric_Type (Target_Type) then
996ae0b0 12257
aa180613 12258 -- A universal fixed expression can be converted to any numeric type
996ae0b0 12259
996ae0b0
RK		 12260 if Opnd_Type = Universal_Fixed then
12261 return True;
7324bf49 12262
aa180613
RD		 12263 -- Also no need to check when in an instance or inlined body, because
12264 -- the legality has been established when the template was analyzed.
12265 -- Furthermore, numeric conversions may occur where only a private
f3d57416 12266 -- view of the operand type is visible at the instantiation point.
aa180613
RD		 12267 -- This results in a spurious error if we check that the operand type
12268 -- is a numeric type.
12269
12270 -- Note: in a previous version of this unit, the following tests were
12271 -- applied only for generated code (Comes_From_Source set to False),
12272 -- but in fact the test is required for source code as well, since
12273 -- this situation can arise in source code.
12274
12275 elsif In_Instance or else In_Inlined_Body then
d347f572 12276 return True;
aa180613
RD		 12277
12278 -- Otherwise we need the conversion check
7324bf49 12279
996ae0b0 12280 else
aa180613 12281 return Conversion_Check
6fd0a72a
AC		 12282 (Is_Numeric_Type (Opnd_Type)
12283 or else
12284 (Present (Inc_Ancestor)
12285 and then Is_Numeric_Type (Inc_Ancestor)),
12286 "illegal operand for numeric conversion");
996ae0b0
RK		 12287 end if;
12288
aa180613
RD		 12289 -- Array types
12290
996ae0b0
RK		 12291 elsif Is_Array_Type (Target_Type) then
12292 if not Is_Array_Type (Opnd_Type)
12293 or else Opnd_Type = Any_Composite
12294 or else Opnd_Type = Any_String
12295 then
1486a00e
AC		 12296 Conversion_Error_N
12297 ("illegal operand for array conversion", Operand);
996ae0b0 12298 return False;
b2502161 12299
996ae0b0 12300 else
aa180613 12301 return Valid_Array_Conversion;
996ae0b0
RK		 12302 end if;
12303
4b963531
AC		 12304 -- Ada 2005 (AI-251): Internally generated conversions of access to
12305 -- interface types added to force the displacement of the pointer to
12306 -- reference the corresponding dispatch table.
12307
12308 elsif not Comes_From_Source (N)
12309 and then Is_Access_Type (Target_Type)
12310 and then Is_Interface (Designated_Type (Target_Type))
12311 then
12312 return True;
12313
e65f50ec
ES		 12314 -- Ada 2005 (AI-251): Anonymous access types where target references an
12315 -- interface type.
758c442c 12316
966fc9c5
AC		 12317 elsif Is_Access_Type (Opnd_Type)
12318 and then Ekind_In (Target_Type, E_General_Access_Type,
12319 E_Anonymous_Access_Type)
758c442c
GD		 12320 and then Is_Interface (Directly_Designated_Type (Target_Type))
12321 then
12322 -- Check the static accessibility rule of 4.6(17). Note that the
d81b4bfe
TQ		 12323 -- check is not enforced when within an instance body, since the
12324 -- RM requires such cases to be caught at run time.
758c442c 12325
4172a8e3
AC		 12326 -- If the operand is a rewriting of an allocator no check is needed
12327 -- because there are no accessibility issues.
12328
12329 if Nkind (Original_Node (N)) = N_Allocator then
12330 null;
12331
12332 elsif Ekind (Target_Type) /= E_Anonymous_Access_Type then
758c442c 12333 if Type_Access_Level (Opnd_Type) >
996c8821 12334 Deepest_Type_Access_Level (Target_Type)
758c442c
GD		 12335 then
12336 -- In an instance, this is a run-time check, but one we know
12337 -- will fail, so generate an appropriate warning. The raise
12338 -- will be generated by Expand_N_Type_Conversion.
12339
12340 if In_Instance_Body then
43417b90 12341 Error_Msg_Warn := SPARK_Mode /= On;
1486a00e 12342 Conversion_Error_N
4a28b181 12343 ("cannot convert local pointer to non-local access type<<",
758c442c 12344 Operand);
4a28b181 12345 Conversion_Error_N ("\Program_Error [<<", Operand);
996c8821 12346
758c442c 12347 else
1486a00e 12348 Conversion_Error_N
758c442c
GD		 12349 ("cannot convert local pointer to non-local access type",
12350 Operand);
12351 return False;
12352 end if;
12353
12354 -- Special accessibility checks are needed in the case of access
12355 -- discriminants declared for a limited type.
12356
12357 elsif Ekind (Opnd_Type) = E_Anonymous_Access_Type
12358 and then not Is_Local_Anonymous_Access (Opnd_Type)
12359 then
12360 -- When the operand is a selected access discriminant the check
12361 -- needs to be made against the level of the object denoted by
d81b4bfe
TQ		 12362 -- the prefix of the selected name (Object_Access_Level handles
12363 -- checking the prefix of the operand for this case).
758c442c
GD		 12364
12365 if Nkind (Operand) = N_Selected_Component
c8ef728f 12366 and then Object_Access_Level (Operand) >
d15f9422 12367 Deepest_Type_Access_Level (Target_Type)
758c442c 12368 then
d81b4bfe
TQ		 12369 -- In an instance, this is a run-time check, but one we know
12370 -- will fail, so generate an appropriate warning. The raise
12371 -- will be generated by Expand_N_Type_Conversion.
758c442c
GD		 12372
12373 if In_Instance_Body then
43417b90 12374 Error_Msg_Warn := SPARK_Mode /= On;
1486a00e 12375 Conversion_Error_N
4a28b181
AC		 12376 ("cannot convert access discriminant to non-local "
12377 & "access type<<", Operand);
12378 Conversion_Error_N ("\Program_Error [<<", Operand);
12379
12380 -- Real error if not in instance body
12381
758c442c 12382 else
1486a00e
AC		 12383 Conversion_Error_N
12384 ("cannot convert access discriminant to non-local "
12385 & "access type", Operand);
758c442c
GD		 12386 return False;
12387 end if;
12388 end if;
12389
12390 -- The case of a reference to an access discriminant from
12391 -- within a limited type declaration (which will appear as
12392 -- a discriminal) is always illegal because the level of the
f3d57416 12393 -- discriminant is considered to be deeper than any (nameable)
758c442c
GD		 12394 -- access type.
12395
12396 if Is_Entity_Name (Operand)
12397 and then not Is_Local_Anonymous_Access (Opnd_Type)
964f13da
RD		 12398 and then
12399 Ekind_In (Entity (Operand), E_In_Parameter, E_Constant)
758c442c
GD		 12400 and then Present (Discriminal_Link (Entity (Operand)))
12401 then
1486a00e 12402 Conversion_Error_N
758c442c
GD		 12403 ("discriminant has deeper accessibility level than target",
12404 Operand);
12405 return False;
12406 end if;
12407 end if;
12408 end if;
12409
12410 return True;
12411
aa180613
RD		 12412 -- General and anonymous access types
12413
964f13da
RD		 12414 elsif Ekind_In (Target_Type, E_General_Access_Type,
12415 E_Anonymous_Access_Type)
996ae0b0
RK		 12416 and then
12417 Conversion_Check
12418 (Is_Access_Type (Opnd_Type)
964f13da
RD		 12419 and then not
12420 Ekind_In (Opnd_Type, E_Access_Subprogram_Type,
12421 E_Access_Protected_Subprogram_Type),
996ae0b0
RK		 12422 "must be an access-to-object type")
12423 then
12424 if Is_Access_Constant (Opnd_Type)
12425 and then not Is_Access_Constant (Target_Type)
12426 then
1486a00e 12427 Conversion_Error_N
996ae0b0
RK		 12428 ("access-to-constant operand type not allowed", Operand);
12429 return False;
12430 end if;
12431
758c442c
GD		 12432 -- Check the static accessibility rule of 4.6(17). Note that the
12433 -- check is not enforced when within an instance body, since the RM
12434 -- requires such cases to be caught at run time.
996ae0b0 12435
758c442c
GD		 12436 if Ekind (Target_Type) /= E_Anonymous_Access_Type
12437 or else Is_Local_Anonymous_Access (Target_Type)
d15f9422 12438 or else Nkind (Associated_Node_For_Itype (Target_Type)) =
996c8821 12439 N_Object_Declaration
758c442c 12440 then
6cce2156
GD		 12441 -- Ada 2012 (AI05-0149): Perform legality checking on implicit
12442 -- conversions from an anonymous access type to a named general
12443 -- access type. Such conversions are not allowed in the case of
12444 -- access parameters and stand-alone objects of an anonymous
c199ccf7
AC		 12445 -- access type. The implicit conversion case is recognized by
12446 -- testing that Comes_From_Source is False and that it's been
12447 -- rewritten. The Comes_From_Source test isn't sufficient because
12448 -- nodes in inlined calls to predefined library routines can have
12449 -- Comes_From_Source set to False. (Is there a better way to test
12450 -- for implicit conversions???)
6cce2156
GD		 12451
12452 if Ada_Version >= Ada_2012
12453 and then not Comes_From_Source (N)
c199ccf7 12454 and then N /= Original_Node (N)
6cce2156
GD		 12455 and then Ekind (Target_Type) = E_General_Access_Type
12456 and then Ekind (Opnd_Type) = E_Anonymous_Access_Type
996ae0b0 12457 then
6cce2156
GD		 12458 if Is_Itype (Opnd_Type) then
12459
12460 -- Implicit conversions aren't allowed for objects of an
12461 -- anonymous access type, since such objects have nonstatic
12462 -- levels in Ada 2012.
12463
12464 if Nkind (Associated_Node_For_Itype (Opnd_Type)) =
12465 N_Object_Declaration
12466 then
1486a00e
AC		 12467 Conversion_Error_N
12468 ("implicit conversion of stand-alone anonymous "
12469 & "access object not allowed", Operand);
6cce2156
GD		 12470 return False;
12471
12472 -- Implicit conversions aren't allowed for anonymous access
12473 -- parameters. The "not Is_Local_Anonymous_Access_Type" test
12474 -- is done to exclude anonymous access results.
12475
12476 elsif not Is_Local_Anonymous_Access (Opnd_Type)
12477 and then Nkind_In (Associated_Node_For_Itype (Opnd_Type),
12478 N_Function_Specification,
12479 N_Procedure_Specification)
12480 then
1486a00e
AC		 12481 Conversion_Error_N
12482 ("implicit conversion of anonymous access formal "
12483 & "not allowed", Operand);
6cce2156
GD		 12484 return False;
12485
12486 -- This is a case where there's an enclosing object whose
12487 -- to which the "statically deeper than" relationship does
12488 -- not apply (such as an access discriminant selected from
12489 -- a dereference of an access parameter).
12490
12491 elsif Object_Access_Level (Operand)
12492 = Scope_Depth (Standard_Standard)
12493 then
1486a00e
AC		 12494 Conversion_Error_N
12495 ("implicit conversion of anonymous access value "
12496 & "not allowed", Operand);
6cce2156
GD		 12497 return False;
12498
12499 -- In other cases, the level of the operand's type must be
12500 -- statically less deep than that of the target type, else
12501 -- implicit conversion is disallowed (by RM12-8.6(27.1/3)).
12502
d15f9422 12503 elsif Type_Access_Level (Opnd_Type) >
996c8821 12504 Deepest_Type_Access_Level (Target_Type)
6cce2156 12505 then
1486a00e
AC		 12506 Conversion_Error_N
12507 ("implicit conversion of anonymous access value "
12508 & "violates accessibility", Operand);
6cce2156
GD		 12509 return False;
12510 end if;
12511 end if;
12512
d15f9422 12513 elsif Type_Access_Level (Opnd_Type) >
996c8821 12514 Deepest_Type_Access_Level (Target_Type)
6cce2156 12515 then
d81b4bfe
TQ		 12516 -- In an instance, this is a run-time check, but one we know
12517 -- will fail, so generate an appropriate warning. The raise
12518 -- will be generated by Expand_N_Type_Conversion.
996ae0b0
RK		 12519
12520 if In_Instance_Body then
43417b90 12521 Error_Msg_Warn := SPARK_Mode /= On;
1486a00e 12522 Conversion_Error_N
4a28b181 12523 ("cannot convert local pointer to non-local access type<<",
996ae0b0 12524 Operand);
4a28b181
AC		 12525 Conversion_Error_N ("\Program_Error [<<", Operand);
12526
12527 -- If not in an instance body, this is a real error
996ae0b0
RK		 12528
12529 else
b90cfacd
HK		 12530 -- Avoid generation of spurious error message
12531
12532 if not Error_Posted (N) then
1486a00e 12533 Conversion_Error_N
b90cfacd
HK		 12534 ("cannot convert local pointer to non-local access type",
12535 Operand);
12536 end if;
12537
996ae0b0
RK		 12538 return False;
12539 end if;
12540
758c442c
GD		 12541 -- Special accessibility checks are needed in the case of access
12542 -- discriminants declared for a limited type.
12543
12544 elsif Ekind (Opnd_Type) = E_Anonymous_Access_Type
12545 and then not Is_Local_Anonymous_Access (Opnd_Type)
12546 then
758c442c
GD		 12547 -- When the operand is a selected access discriminant the check
12548 -- needs to be made against the level of the object denoted by
d81b4bfe
TQ		 12549 -- the prefix of the selected name (Object_Access_Level handles
12550 -- checking the prefix of the operand for this case).
996ae0b0
RK		 12551
12552 if Nkind (Operand) = N_Selected_Component
45fc7ddb 12553 and then Object_Access_Level (Operand) >
996c8821 12554 Deepest_Type_Access_Level (Target_Type)
996ae0b0 12555 then
d81b4bfe
TQ		 12556 -- In an instance, this is a run-time check, but one we know
12557 -- will fail, so generate an appropriate warning. The raise
12558 -- will be generated by Expand_N_Type_Conversion.
996ae0b0
RK		 12559
12560 if In_Instance_Body then
43417b90 12561 Error_Msg_Warn := SPARK_Mode /= On;
1486a00e 12562 Conversion_Error_N
4a28b181
AC		 12563 ("cannot convert access discriminant to non-local "
12564 & "access type<<", Operand);
12565 Conversion_Error_N ("\Program_Error [<<", Operand);
12566
12567 -- If not in an instance body, this is a real error
996ae0b0
RK		 12568
12569 else
1486a00e
AC		 12570 Conversion_Error_N
12571 ("cannot convert access discriminant to non-local "
12572 & "access type", Operand);
996ae0b0
RK		 12573 return False;
12574 end if;
12575 end if;
12576
758c442c
GD		 12577 -- The case of a reference to an access discriminant from
12578 -- within a limited type declaration (which will appear as
12579 -- a discriminal) is always illegal because the level of the
f3d57416 12580 -- discriminant is considered to be deeper than any (nameable)
758c442c 12581 -- access type.
996ae0b0
RK		 12582
12583 if Is_Entity_Name (Operand)
964f13da
RD		 12584 and then
12585 Ekind_In (Entity (Operand), E_In_Parameter, E_Constant)
996ae0b0
RK		 12586 and then Present (Discriminal_Link (Entity (Operand)))
12587 then
1486a00e 12588 Conversion_Error_N
996ae0b0
RK		 12589 ("discriminant has deeper accessibility level than target",
12590 Operand);
12591 return False;
12592 end if;
12593 end if;
12594 end if;
12595
e4dc3327 12596 -- In the presence of limited_with clauses we have to use nonlimited
14e33999 12597 -- views, if available.
d81b4bfe 12598
14e33999 12599 Check_Limited : declare
0669bebe
GB		 12600 function Full_Designated_Type (T : Entity_Id) return Entity_Id;
12601 -- Helper function to handle limited views
12602
12603 --------------------------
12604 -- Full_Designated_Type --
12605 --------------------------
12606
12607 function Full_Designated_Type (T : Entity_Id) return Entity_Id is
950d217a 12608 Desig : constant Entity_Id := Designated_Type (T);
c0985d4e 12609
0669bebe 12610 begin
950d217a
AC		 12611 -- Handle the limited view of a type
12612
47346923
AC		 12613 if From_Limited_With (Desig)
12614 and then Has_Non_Limited_View (Desig)
0669bebe 12615 then
950d217a
AC		 12616 return Available_View (Desig);
12617 else
12618 return Desig;
0669bebe
GB		 12619 end if;
12620 end Full_Designated_Type;
12621
d81b4bfe
TQ		 12622 -- Local Declarations
12623
0669bebe
GB		 12624 Target : constant Entity_Id := Full_Designated_Type (Target_Type);
12625 Opnd : constant Entity_Id := Full_Designated_Type (Opnd_Type);
12626
12627 Same_Base : constant Boolean :=
12628 Base_Type (Target) = Base_Type (Opnd);
996ae0b0 12629
14e33999 12630 -- Start of processing for Check_Limited
d81b4bfe 12631
996ae0b0
RK		 12632 begin
12633 if Is_Tagged_Type (Target) then
12634 return Valid_Tagged_Conversion (Target, Opnd);
12635
12636 else
0669bebe 12637 if not Same_Base then
1486a00e 12638 Conversion_Error_NE
996ae0b0
RK		 12639 ("target designated type not compatible with }",
12640 N, Base_Type (Opnd));
12641 return False;
12642
da709d08
AC		 12643 -- Ada 2005 AI-384: legality rule is symmetric in both
12644 -- designated types. The conversion is legal (with possible
12645 -- constraint check) if either designated type is
12646 -- unconstrained.
12647
12648 elsif Subtypes_Statically_Match (Target, Opnd)
12649 or else
12650 (Has_Discriminants (Target)
12651 and then
12652 (not Is_Constrained (Opnd)
12653 or else not Is_Constrained (Target)))
996ae0b0 12654 then
9fa33291
RD		 12655 -- Special case, if Value_Size has been used to make the
12656 -- sizes different, the conversion is not allowed even
12657 -- though the subtypes statically match.
12658
12659 if Known_Static_RM_Size (Target)
12660 and then Known_Static_RM_Size (Opnd)
12661 and then RM_Size (Target) /= RM_Size (Opnd)
12662 then
1486a00e 12663 Conversion_Error_NE
9fa33291
RD		 12664 ("target designated subtype not compatible with }",
12665 N, Opnd);
1486a00e 12666 Conversion_Error_NE
9fa33291
RD		 12667 ("\because sizes of the two designated subtypes differ",
12668 N, Opnd);
12669 return False;
12670
12671 -- Normal case where conversion is allowed
12672
12673 else
12674 return True;
12675 end if;
da709d08
AC		 12676
12677 else
996ae0b0
RK		 12678 Error_Msg_NE
12679 ("target designated subtype not compatible with }",
12680 N, Opnd);
12681 return False;
996ae0b0
RK		 12682 end if;
12683 end if;
14e33999 12684 end Check_Limited;
996ae0b0 12685
cdbf04c0 12686 -- Access to subprogram types. If the operand is an access parameter,
4adf3c50
AC		 12687 -- the type has a deeper accessibility that any master, and cannot be
12688 -- assigned. We must make an exception if the conversion is part of an
12689 -- assignment and the target is the return object of an extended return
12690 -- statement, because in that case the accessibility check takes place
12691 -- after the return.
aa180613 12692
dce86910 12693 elsif Is_Access_Subprogram_Type (Target_Type)
b07b7ace 12694
3f1bc2cf
AC		 12695 -- Note: this test of Opnd_Type is there to prevent entering this
12696 -- branch in the case of a remote access to subprogram type, which
12697 -- is internally represented as an E_Record_Type.
b07b7ace 12698
3f1bc2cf 12699 and then Is_Access_Type (Opnd_Type)
996ae0b0 12700 then
cdbf04c0
AC		 12701 if Ekind (Base_Type (Opnd_Type)) = E_Anonymous_Access_Subprogram_Type
12702 and then Is_Entity_Name (Operand)
12703 and then Ekind (Entity (Operand)) = E_In_Parameter
53cf4600
ES		 12704 and then
12705 (Nkind (Parent (N)) /= N_Assignment_Statement
12706 or else not Is_Entity_Name (Name (Parent (N)))
12707 or else not Is_Return_Object (Entity (Name (Parent (N)))))
0669bebe 12708 then
1486a00e 12709 Conversion_Error_N
0669bebe
GB		 12710 ("illegal attempt to store anonymous access to subprogram",
12711 Operand);
1486a00e
AC		 12712 Conversion_Error_N
12713 ("\value has deeper accessibility than any master "
12714 & "(RM 3.10.2 (13))",
0669bebe
GB		 12715 Operand);
12716
c147ac26
ES		 12717 Error_Msg_NE
12718 ("\use named access type for& instead of access parameter",
12719 Operand, Entity (Operand));
0669bebe
GB		 12720 end if;
12721
996ae0b0
RK		 12722 -- Check that the designated types are subtype conformant
12723
bc5f3720
RD		 12724 Check_Subtype_Conformant (New_Id => Designated_Type (Target_Type),
12725 Old_Id => Designated_Type (Opnd_Type),
12726 Err_Loc => N);
996ae0b0
RK		 12727
12728 -- Check the static accessibility rule of 4.6(20)
12729
12730 if Type_Access_Level (Opnd_Type) >
996c8821 12731 Deepest_Type_Access_Level (Target_Type)
996ae0b0 12732 then
1486a00e 12733 Conversion_Error_N
996ae0b0
RK		 12734 ("operand type has deeper accessibility level than target",
12735 Operand);
12736
12737 -- Check that if the operand type is declared in a generic body,
12738 -- then the target type must be declared within that same body
12739 -- (enforces last sentence of 4.6(20)).
12740
12741 elsif Present (Enclosing_Generic_Body (Opnd_Type)) then
12742 declare
12743 O_Gen : constant Node_Id :=
12744 Enclosing_Generic_Body (Opnd_Type);
12745
1420b484 12746 T_Gen : Node_Id;
996ae0b0
RK		 12747
12748 begin
1420b484 12749 T_Gen := Enclosing_Generic_Body (Target_Type);
996ae0b0
RK		 12750 while Present (T_Gen) and then T_Gen /= O_Gen loop
12751 T_Gen := Enclosing_Generic_Body (T_Gen);
12752 end loop;
12753
12754 if T_Gen /= O_Gen then
1486a00e
AC		 12755 Conversion_Error_N
12756 ("target type must be declared in same generic body "
12757 & "as operand type", N);
996ae0b0
RK		 12758 end if;
12759 end;
12760 end if;
12761
12762 return True;
12763
b07b7ace 12764 -- Remote access to subprogram types
aa180613 12765
996ae0b0
RK		 12766 elsif Is_Remote_Access_To_Subprogram_Type (Target_Type)
12767 and then Is_Remote_Access_To_Subprogram_Type (Opnd_Type)
12768 then
12769 -- It is valid to convert from one RAS type to another provided
12770 -- that their specification statically match.
12771
b07b7ace
AC		 12772 -- Note: at this point, remote access to subprogram types have been
12773 -- expanded to their E_Record_Type representation, and we need to
12774 -- go back to the original access type definition using the
12775 -- Corresponding_Remote_Type attribute in order to check that the
12776 -- designated profiles match.
12777
12778 pragma Assert (Ekind (Target_Type) = E_Record_Type);
12779 pragma Assert (Ekind (Opnd_Type) = E_Record_Type);
12780
996ae0b0
RK		 12781 Check_Subtype_Conformant
12782 (New_Id =>
12783 Designated_Type (Corresponding_Remote_Type (Target_Type)),
12784 Old_Id =>
12785 Designated_Type (Corresponding_Remote_Type (Opnd_Type)),
12786 Err_Loc =>
12787 N);
12788 return True;
aa180613 12789
be482a8c
AC		 12790 -- If it was legal in the generic, it's legal in the instance
12791
12792 elsif In_Instance_Body then
12793 return True;
12794
e65f50ec 12795 -- If both are tagged types, check legality of view conversions
996ae0b0 12796
e65f50ec 12797 elsif Is_Tagged_Type (Target_Type)
4adf3c50
AC		 12798 and then
12799 Is_Tagged_Type (Opnd_Type)
e65f50ec 12800 then
996ae0b0
RK		 12801 return Valid_Tagged_Conversion (Target_Type, Opnd_Type);
12802
a77842bd 12803 -- Types derived from the same root type are convertible
996ae0b0
RK		 12804
12805 elsif Root_Type (Target_Type) = Root_Type (Opnd_Type) then
12806 return True;
12807
4adf3c50
AC		 12808 -- In an instance or an inlined body, there may be inconsistent views of
12809 -- the same type, or of types derived from a common root.
996ae0b0 12810
aa5147f0
ES		 12811 elsif (In_Instance or In_Inlined_Body)
12812 and then
d81b4bfe
TQ		 12813 Root_Type (Underlying_Type (Target_Type)) =
12814 Root_Type (Underlying_Type (Opnd_Type))
996ae0b0
RK		 12815 then
12816 return True;
12817
12818 -- Special check for common access type error case
12819
12820 elsif Ekind (Target_Type) = E_Access_Type
12821 and then Is_Access_Type (Opnd_Type)
12822 then
1486a00e
AC		 12823 Conversion_Error_N ("target type must be general access type!", N);
12824 Conversion_Error_NE -- CODEFIX
305caf42 12825 ("add ALL to }!", N, Target_Type);
996ae0b0
RK		 12826 return False;
12827
818b578d
AC		 12828 -- Here we have a real conversion error
12829
996ae0b0 12830 else
1486a00e
AC		 12831 Conversion_Error_NE
12832 ("invalid conversion, not compatible with }", N, Opnd_Type);
996ae0b0
RK		 12833 return False;
12834 end if;
12835 end Valid_Conversion;
12836
12837end Sem_Res;
GNU Compiler Collection
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