1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- F R E E Z E -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1992-2021, Free Software Foundation, Inc. -- 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- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- 17-- for more details. You should have received a copy of the GNU General -- 18-- Public License distributed with GNAT; see file COPYING3. If not, go to -- 19-- http://www.gnu.org/licenses for a complete copy of the license. -- 20-- -- 21-- GNAT was originally developed by the GNAT team at New York University. -- 22-- Extensive contributions were provided by Ada Core Technologies Inc. -- 23-- -- 24------------------------------------------------------------------------------ 25 26with Aspects; use Aspects; 27with Atree; use Atree; 28with Checks; use Checks; 29with Contracts; use Contracts; 30with Debug; use Debug; 31with Einfo; use Einfo; 32with Einfo.Entities; use Einfo.Entities; 33with Einfo.Utils; use Einfo.Utils; 34with Elists; use Elists; 35with Errout; use Errout; 36with Exp_Ch3; use Exp_Ch3; 37with Exp_Ch7; use Exp_Ch7; 38with Exp_Disp; use Exp_Disp; 39with Exp_Pakd; use Exp_Pakd; 40with Exp_Util; use Exp_Util; 41with Exp_Tss; use Exp_Tss; 42with Ghost; use Ghost; 43with Layout; use Layout; 44with Lib; use Lib; 45with Namet; use Namet; 46with Nlists; use Nlists; 47with Nmake; use Nmake; 48with Opt; use Opt; 49with Restrict; use Restrict; 50with Rident; use Rident; 51with Rtsfind; use Rtsfind; 52with Sem; use Sem; 53with Sem_Aux; use Sem_Aux; 54with Sem_Cat; use Sem_Cat; 55with Sem_Ch3; use Sem_Ch3; 56with Sem_Ch6; use Sem_Ch6; 57with Sem_Ch7; use Sem_Ch7; 58with Sem_Ch8; use Sem_Ch8; 59with Sem_Ch13; use Sem_Ch13; 60with Sem_Disp; use Sem_Disp; 61with Sem_Eval; use Sem_Eval; 62with Sem_Mech; use Sem_Mech; 63with Sem_Prag; use Sem_Prag; 64with Sem_Res; use Sem_Res; 65with Sem_Util; use Sem_Util; 66with Sinfo; use Sinfo; 67with Sinfo.Nodes; use Sinfo.Nodes; 68with Sinfo.Utils; use Sinfo.Utils; 69with Snames; use Snames; 70with Stand; use Stand; 71with Stringt; use Stringt; 72with Strub; use Strub; 73with Targparm; use Targparm; 74with Tbuild; use Tbuild; 75with Ttypes; use Ttypes; 76with Uintp; use Uintp; 77with Urealp; use Urealp; 78with Warnsw; use Warnsw; 79 80package body Freeze is 81 82 ----------------------- 83 -- Local Subprograms -- 84 ----------------------- 85 86 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id); 87 -- Typ is a type that is being frozen. If no size clause is given, 88 -- but a default Esize has been computed, then this default Esize is 89 -- adjusted up if necessary to be consistent with a given alignment, 90 -- but never to a value greater than System_Max_Integer_Size. This is 91 -- used for all discrete types and for fixed-point types. 92 93 procedure Build_And_Analyze_Renamed_Body 94 (Decl : Node_Id; 95 New_S : Entity_Id; 96 After : in out Node_Id); 97 -- Build body for a renaming declaration, insert in tree and analyze 98 99 procedure Check_Address_Clause (E : Entity_Id); 100 -- Apply legality checks to address clauses for object declarations, 101 -- at the point the object is frozen. Also ensure any initialization is 102 -- performed only after the object has been frozen. 103 104 procedure Check_Component_Storage_Order 105 (Encl_Type : Entity_Id; 106 Comp : Entity_Id; 107 ADC : Node_Id; 108 Comp_ADC_Present : out Boolean); 109 -- For an Encl_Type that has a Scalar_Storage_Order attribute definition 110 -- clause, verify that the component type has an explicit and compatible 111 -- attribute/aspect. For arrays, Comp is Empty; for records, it is the 112 -- entity of the component under consideration. For an Encl_Type that 113 -- does not have a Scalar_Storage_Order attribute definition clause, 114 -- verify that the component also does not have such a clause. 115 -- ADC is the attribute definition clause if present (or Empty). On return, 116 -- Comp_ADC_Present is set True if the component has a Scalar_Storage_Order 117 -- attribute definition clause. 118 119 procedure Check_Debug_Info_Needed (T : Entity_Id); 120 -- As each entity is frozen, this routine is called to deal with the 121 -- setting of Debug_Info_Needed for the entity. This flag is set if 122 -- the entity comes from source, or if we are in Debug_Generated_Code 123 -- mode or if the -gnatdV debug flag is set. However, it never sets 124 -- the flag if Debug_Info_Off is set. This procedure also ensures that 125 -- subsidiary entities have the flag set as required. 126 127 procedure Check_Expression_Function (N : Node_Id; Nam : Entity_Id); 128 -- When an expression function is frozen by a use of it, the expression 129 -- itself is frozen. Check that the expression does not include references 130 -- to deferred constants without completion. We report this at the freeze 131 -- point of the function, to provide a better error message. 132 -- 133 -- In most cases the expression itself is frozen by the time the function 134 -- itself is frozen, because the formals will be frozen by then. However, 135 -- Attribute references to outer types are freeze points for those types; 136 -- this routine generates the required freeze nodes for them. 137 138 procedure Check_Strict_Alignment (E : Entity_Id); 139 -- E is a base type. If E is tagged or has a component that is aliased 140 -- or tagged or contains something this is aliased or tagged, set 141 -- Strict_Alignment. 142 143 procedure Check_Unsigned_Type (E : Entity_Id); 144 pragma Inline (Check_Unsigned_Type); 145 -- If E is a fixed-point or discrete type, then all the necessary work 146 -- to freeze it is completed except for possible setting of the flag 147 -- Is_Unsigned_Type, which is done by this procedure. The call has no 148 -- effect if the entity E is not a discrete or fixed-point type. 149 150 procedure Freeze_And_Append 151 (Ent : Entity_Id; 152 N : Node_Id; 153 Result : in out List_Id); 154 -- Freezes Ent using Freeze_Entity, and appends the resulting list of 155 -- nodes to Result, modifying Result from No_List if necessary. N has 156 -- the same usage as in Freeze_Entity. 157 158 procedure Freeze_Enumeration_Type (Typ : Entity_Id); 159 -- Freeze enumeration type. The Esize field is set as processing 160 -- proceeds (i.e. set by default when the type is declared and then 161 -- adjusted by rep clauses). What this procedure does is to make sure 162 -- that if a foreign convention is specified, and no specific size 163 -- is given, then the size must be at least Integer'Size. 164 165 procedure Freeze_Static_Object (E : Entity_Id); 166 -- If an object is frozen which has Is_Statically_Allocated set, then 167 -- all referenced types must also be marked with this flag. This routine 168 -- is in charge of meeting this requirement for the object entity E. 169 170 procedure Freeze_Subprogram (E : Entity_Id); 171 -- Perform freezing actions for a subprogram (create extra formals, 172 -- and set proper default mechanism values). Note that this routine 173 -- is not called for internal subprograms, for which neither of these 174 -- actions is needed (or desirable, we do not want for example to have 175 -- these extra formals present in initialization procedures, where they 176 -- would serve no purpose). In this call E is either a subprogram or 177 -- a subprogram type (i.e. an access to a subprogram). 178 179 function Is_Fully_Defined (T : Entity_Id) return Boolean; 180 -- True if T is not private and has no private components, or has a full 181 -- view. Used to determine whether the designated type of an access type 182 -- should be frozen when the access type is frozen. This is done when an 183 -- allocator is frozen, or an expression that may involve attributes of 184 -- the designated type. Otherwise freezing the access type does not freeze 185 -- the designated type. 186 187 function Should_Freeze_Type (Typ : Entity_Id; E : Entity_Id) return Boolean; 188 -- If Typ is in the current scope or in an instantiation, then return True. 189 -- ???Expression functions (represented by E) shouldn't freeze types in 190 -- general, but our current expansion and freezing model requires an early 191 -- freezing when the dispatch table is needed or when building an aggregate 192 -- with a subtype of Typ, so return True also in this case. 193 -- Note that expression function completions do freeze and are 194 -- handled in Sem_Ch6.Analyze_Expression_Function. 195 196 ------------------------ 197 -- Should_Freeze_Type -- 198 ------------------------ 199 200 function Should_Freeze_Type 201 (Typ : Entity_Id; E : Entity_Id) return Boolean 202 is 203 function Is_Dispatching_Call_Or_Aggregate 204 (N : Node_Id) return Traverse_Result; 205 -- Return Abandon if N is a dispatching call to a subprogram 206 -- declared in the same scope as Typ or an aggregate whose type 207 -- is Typ. 208 209 -------------------------------------- 210 -- Is_Dispatching_Call_Or_Aggregate -- 211 -------------------------------------- 212 213 function Is_Dispatching_Call_Or_Aggregate 214 (N : Node_Id) return Traverse_Result is 215 begin 216 if Nkind (N) = N_Function_Call 217 and then Present (Controlling_Argument (N)) 218 and then Scope (Entity (Original_Node (Name (N)))) 219 = Scope (Typ) 220 then 221 return Abandon; 222 elsif Nkind (N) = N_Aggregate 223 and then Base_Type (Etype (N)) = Base_Type (Typ) 224 then 225 return Abandon; 226 else 227 return OK; 228 end if; 229 end Is_Dispatching_Call_Or_Aggregate; 230 231 ------------------------- 232 -- Need_Dispatch_Table -- 233 ------------------------- 234 235 function Need_Dispatch_Table is new 236 Traverse_Func (Is_Dispatching_Call_Or_Aggregate); 237 -- Return Abandon if the input expression requires access to 238 -- Typ's dispatch table. 239 240 Decl : constant Node_Id := 241 (if No (E) then E else Original_Node (Unit_Declaration_Node (E))); 242 243 -- Start of processing for Should_Freeze_Type 244 245 begin 246 return Within_Scope (Typ, Current_Scope) 247 or else In_Instance 248 or else (Present (Decl) 249 and then Nkind (Decl) = N_Expression_Function 250 and then Need_Dispatch_Table (Expression (Decl)) = Abandon); 251 end Should_Freeze_Type; 252 253 procedure Process_Default_Expressions 254 (E : Entity_Id; 255 After : in out Node_Id); 256 -- This procedure is called for each subprogram to complete processing of 257 -- default expressions at the point where all types are known to be frozen. 258 -- The expressions must be analyzed in full, to make sure that all error 259 -- processing is done (they have only been preanalyzed). If the expression 260 -- is not an entity or literal, its analysis may generate code which must 261 -- not be executed. In that case we build a function body to hold that 262 -- code. This wrapper function serves no other purpose (it used to be 263 -- called to evaluate the default, but now the default is inlined at each 264 -- point of call). 265 266 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id); 267 -- Typ is a record or array type that is being frozen. This routine sets 268 -- the default component alignment from the scope stack values if the 269 -- alignment is otherwise not specified. 270 271 procedure Set_SSO_From_Default (T : Entity_Id); 272 -- T is a record or array type that is being frozen. If it is a base type, 273 -- and if SSO_Set_Low/High_By_Default is set, then Reverse_Storage order 274 -- will be set appropriately. Note that an explicit occurrence of aspect 275 -- Scalar_Storage_Order or an explicit setting of this aspect with an 276 -- attribute definition clause occurs, then these two flags are reset in 277 -- any case, so call will have no effect. 278 279 procedure Undelay_Type (T : Entity_Id); 280 -- T is a type of a component that we know to be an Itype. We don't want 281 -- this to have a Freeze_Node, so ensure it doesn't. Do the same for any 282 -- Full_View or Corresponding_Record_Type. 283 284 procedure Warn_Overlay (Expr : Node_Id; Typ : Entity_Id; Nam : Node_Id); 285 -- Expr is the expression for an address clause for the entity denoted by 286 -- Nam whose type is Typ. If Typ has a default initialization, and there is 287 -- no explicit initialization in the source declaration, check whether the 288 -- address clause might cause overlaying of an entity, and emit a warning 289 -- on the side effect that the initialization will cause. 290 291 ------------------------------- 292 -- Adjust_Esize_For_Alignment -- 293 ------------------------------- 294 295 procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is 296 Align : Uint; 297 298 begin 299 if Known_Esize (Typ) and then Known_Alignment (Typ) then 300 Align := Alignment_In_Bits (Typ); 301 302 if Align > Esize (Typ) and then Align <= System_Max_Integer_Size then 303 Set_Esize (Typ, Align); 304 end if; 305 end if; 306 end Adjust_Esize_For_Alignment; 307 308 ------------------------------------ 309 -- Build_And_Analyze_Renamed_Body -- 310 ------------------------------------ 311 312 procedure Build_And_Analyze_Renamed_Body 313 (Decl : Node_Id; 314 New_S : Entity_Id; 315 After : in out Node_Id) 316 is 317 Body_Decl : constant Node_Id := Unit_Declaration_Node (New_S); 318 Ent : constant Entity_Id := Defining_Entity (Decl); 319 Body_Node : Node_Id; 320 Renamed_Subp : Entity_Id; 321 322 begin 323 -- If the renamed subprogram is intrinsic, there is no need for a 324 -- wrapper body: we set the alias that will be called and expanded which 325 -- completes the declaration. This transformation is only legal if the 326 -- renamed entity has already been elaborated. 327 328 -- Note that it is legal for a renaming_as_body to rename an intrinsic 329 -- subprogram, as long as the renaming occurs before the new entity 330 -- is frozen (RM 8.5.4 (5)). 331 332 if Nkind (Body_Decl) = N_Subprogram_Renaming_Declaration 333 and then Is_Entity_Name (Name (Body_Decl)) 334 then 335 Renamed_Subp := Entity (Name (Body_Decl)); 336 else 337 Renamed_Subp := Empty; 338 end if; 339 340 if Present (Renamed_Subp) 341 and then Is_Intrinsic_Subprogram (Renamed_Subp) 342 and then 343 (not In_Same_Source_Unit (Renamed_Subp, Ent) 344 or else Sloc (Renamed_Subp) < Sloc (Ent)) 345 346 -- We can make the renaming entity intrinsic if the renamed function 347 -- has an interface name, or if it is one of the shift/rotate 348 -- operations known to the compiler. 349 350 and then 351 (Present (Interface_Name (Renamed_Subp)) 352 or else Chars (Renamed_Subp) in Name_Rotate_Left 353 | Name_Rotate_Right 354 | Name_Shift_Left 355 | Name_Shift_Right 356 | Name_Shift_Right_Arithmetic) 357 then 358 Set_Interface_Name (Ent, Interface_Name (Renamed_Subp)); 359 360 if Present (Alias (Renamed_Subp)) then 361 Set_Alias (Ent, Alias (Renamed_Subp)); 362 else 363 Set_Alias (Ent, Renamed_Subp); 364 end if; 365 366 Set_Is_Intrinsic_Subprogram (Ent); 367 Set_Has_Completion (Ent); 368 369 else 370 Body_Node := Build_Renamed_Body (Decl, New_S); 371 Insert_After (After, Body_Node); 372 Mark_Rewrite_Insertion (Body_Node); 373 Analyze (Body_Node); 374 After := Body_Node; 375 end if; 376 end Build_And_Analyze_Renamed_Body; 377 378 ------------------------ 379 -- Build_Renamed_Body -- 380 ------------------------ 381 382 function Build_Renamed_Body 383 (Decl : Node_Id; 384 New_S : Entity_Id) return Node_Id 385 is 386 Loc : constant Source_Ptr := Sloc (New_S); 387 -- We use for the source location of the renamed body, the location of 388 -- the spec entity. It might seem more natural to use the location of 389 -- the renaming declaration itself, but that would be wrong, since then 390 -- the body we create would look as though it was created far too late, 391 -- and this could cause problems with elaboration order analysis, 392 -- particularly in connection with instantiations. 393 394 N : constant Node_Id := Unit_Declaration_Node (New_S); 395 Nam : constant Node_Id := Name (N); 396 Old_S : Entity_Id; 397 Spec : constant Node_Id := New_Copy_Tree (Specification (Decl)); 398 Actuals : List_Id := No_List; 399 Call_Node : Node_Id; 400 Call_Name : Node_Id; 401 Body_Node : Node_Id; 402 Formal : Entity_Id; 403 O_Formal : Entity_Id; 404 Param_Spec : Node_Id; 405 406 Pref : Node_Id := Empty; 407 -- If the renamed entity is a primitive operation given in prefix form, 408 -- the prefix is the target object and it has to be added as the first 409 -- actual in the generated call. 410 411 begin 412 -- Determine the entity being renamed, which is the target of the call 413 -- statement. If the name is an explicit dereference, this is a renaming 414 -- of a subprogram type rather than a subprogram. The name itself is 415 -- fully analyzed. 416 417 if Nkind (Nam) = N_Selected_Component then 418 Old_S := Entity (Selector_Name (Nam)); 419 420 elsif Nkind (Nam) = N_Explicit_Dereference then 421 Old_S := Etype (Nam); 422 423 elsif Nkind (Nam) = N_Indexed_Component then 424 if Is_Entity_Name (Prefix (Nam)) then 425 Old_S := Entity (Prefix (Nam)); 426 else 427 Old_S := Entity (Selector_Name (Prefix (Nam))); 428 end if; 429 430 elsif Nkind (Nam) = N_Character_Literal then 431 Old_S := Etype (New_S); 432 433 else 434 Old_S := Entity (Nam); 435 end if; 436 437 if Is_Entity_Name (Nam) then 438 439 -- If the renamed entity is a predefined operator, retain full name 440 -- to ensure its visibility. 441 442 if Ekind (Old_S) = E_Operator 443 and then Nkind (Nam) = N_Expanded_Name 444 then 445 Call_Name := New_Copy (Name (N)); 446 else 447 Call_Name := New_Occurrence_Of (Old_S, Loc); 448 end if; 449 450 else 451 if Nkind (Nam) = N_Selected_Component 452 and then Present (First_Formal (Old_S)) 453 and then 454 (Is_Controlling_Formal (First_Formal (Old_S)) 455 or else Is_Class_Wide_Type (Etype (First_Formal (Old_S)))) 456 then 457 458 -- Retrieve the target object, to be added as a first actual 459 -- in the call. 460 461 Call_Name := New_Occurrence_Of (Old_S, Loc); 462 Pref := Prefix (Nam); 463 464 else 465 Call_Name := New_Copy (Name (N)); 466 end if; 467 468 -- Original name may have been overloaded, but is fully resolved now 469 470 Set_Is_Overloaded (Call_Name, False); 471 end if; 472 473 -- For simple renamings, subsequent calls can be expanded directly as 474 -- calls to the renamed entity. The body must be generated in any case 475 -- for calls that may appear elsewhere. This is not done in the case 476 -- where the subprogram is an instantiation because the actual proper 477 -- body has not been built yet. This is also not done in GNATprove mode 478 -- as we need to check other conditions for creating a body to inline 479 -- in that case, which are controlled in Analyze_Subprogram_Body_Helper. 480 481 if Ekind (Old_S) in E_Function | E_Procedure 482 and then Nkind (Decl) = N_Subprogram_Declaration 483 and then not Is_Generic_Instance (Old_S) 484 and then not GNATprove_Mode 485 then 486 Set_Body_To_Inline (Decl, Old_S); 487 end if; 488 489 -- Check whether the return type is a limited view. If the subprogram 490 -- is already frozen the generated body may have a non-limited view 491 -- of the type, that must be used, because it is the one in the spec 492 -- of the renaming declaration. 493 494 if Ekind (Old_S) = E_Function 495 and then Is_Entity_Name (Result_Definition (Spec)) 496 then 497 declare 498 Ret_Type : constant Entity_Id := Etype (Result_Definition (Spec)); 499 begin 500 if Has_Non_Limited_View (Ret_Type) then 501 Set_Result_Definition 502 (Spec, New_Occurrence_Of (Non_Limited_View (Ret_Type), Loc)); 503 end if; 504 end; 505 end if; 506 507 -- The body generated for this renaming is an internal artifact, and 508 -- does not constitute a freeze point for the called entity. 509 510 Set_Must_Not_Freeze (Call_Name); 511 512 Formal := First_Formal (Defining_Entity (Decl)); 513 514 if Present (Pref) then 515 declare 516 Pref_Type : constant Entity_Id := Etype (Pref); 517 Form_Type : constant Entity_Id := Etype (First_Formal (Old_S)); 518 519 begin 520 -- The controlling formal may be an access parameter, or the 521 -- actual may be an access value, so adjust accordingly. 522 523 if Is_Access_Type (Pref_Type) 524 and then not Is_Access_Type (Form_Type) 525 then 526 Actuals := New_List 527 (Make_Explicit_Dereference (Loc, Relocate_Node (Pref))); 528 529 elsif Is_Access_Type (Form_Type) 530 and then not Is_Access_Type (Pref) 531 then 532 Actuals := 533 New_List ( 534 Make_Attribute_Reference (Loc, 535 Attribute_Name => Name_Access, 536 Prefix => Relocate_Node (Pref))); 537 else 538 Actuals := New_List (Pref); 539 end if; 540 end; 541 542 elsif Present (Formal) then 543 Actuals := New_List; 544 545 else 546 Actuals := No_List; 547 end if; 548 549 while Present (Formal) loop 550 Append (New_Occurrence_Of (Formal, Loc), Actuals); 551 Next_Formal (Formal); 552 end loop; 553 554 -- If the renamed entity is an entry, inherit its profile. For other 555 -- renamings as bodies, both profiles must be subtype conformant, so it 556 -- is not necessary to replace the profile given in the declaration. 557 -- However, default values that are aggregates are rewritten when 558 -- partially analyzed, so we recover the original aggregate to insure 559 -- that subsequent conformity checking works. Similarly, if the default 560 -- expression was constant-folded, recover the original expression. 561 562 Formal := First_Formal (Defining_Entity (Decl)); 563 564 if Present (Formal) then 565 O_Formal := First_Formal (Old_S); 566 Param_Spec := First (Parameter_Specifications (Spec)); 567 while Present (Formal) loop 568 if Is_Entry (Old_S) then 569 if Nkind (Parameter_Type (Param_Spec)) /= 570 N_Access_Definition 571 then 572 Set_Etype (Formal, Etype (O_Formal)); 573 Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal)); 574 end if; 575 576 elsif Nkind (Default_Value (O_Formal)) = N_Aggregate 577 or else Nkind (Original_Node (Default_Value (O_Formal))) /= 578 Nkind (Default_Value (O_Formal)) 579 then 580 Set_Expression (Param_Spec, 581 New_Copy_Tree (Original_Node (Default_Value (O_Formal)))); 582 end if; 583 584 Next_Formal (Formal); 585 Next_Formal (O_Formal); 586 Next (Param_Spec); 587 end loop; 588 end if; 589 590 -- If the renamed entity is a function, the generated body contains a 591 -- return statement. Otherwise, build a procedure call. If the entity is 592 -- an entry, subsequent analysis of the call will transform it into the 593 -- proper entry or protected operation call. If the renamed entity is 594 -- a character literal, return it directly. 595 596 if Ekind (Old_S) = E_Function 597 or else Ekind (Old_S) = E_Operator 598 or else (Ekind (Old_S) = E_Subprogram_Type 599 and then Etype (Old_S) /= Standard_Void_Type) 600 then 601 Call_Node := 602 Make_Simple_Return_Statement (Loc, 603 Expression => 604 Make_Function_Call (Loc, 605 Name => Call_Name, 606 Parameter_Associations => Actuals)); 607 608 elsif Ekind (Old_S) = E_Enumeration_Literal then 609 Call_Node := 610 Make_Simple_Return_Statement (Loc, 611 Expression => New_Occurrence_Of (Old_S, Loc)); 612 613 elsif Nkind (Nam) = N_Character_Literal then 614 Call_Node := 615 Make_Simple_Return_Statement (Loc, Expression => Call_Name); 616 617 else 618 Call_Node := 619 Make_Procedure_Call_Statement (Loc, 620 Name => Call_Name, 621 Parameter_Associations => Actuals); 622 end if; 623 624 -- Create entities for subprogram body and formals 625 626 Set_Defining_Unit_Name (Spec, 627 Make_Defining_Identifier (Loc, Chars => Chars (New_S))); 628 629 Param_Spec := First (Parameter_Specifications (Spec)); 630 while Present (Param_Spec) loop 631 Set_Defining_Identifier (Param_Spec, 632 Make_Defining_Identifier (Loc, 633 Chars => Chars (Defining_Identifier (Param_Spec)))); 634 Next (Param_Spec); 635 end loop; 636 637 -- In GNATprove, prefer to generate an expression function whenever 638 -- possible, to benefit from the more precise analysis in that case 639 -- (as if an implicit postcondition had been generated). 640 641 if GNATprove_Mode 642 and then Nkind (Call_Node) = N_Simple_Return_Statement 643 then 644 Body_Node := 645 Make_Expression_Function (Loc, 646 Specification => Spec, 647 Expression => Expression (Call_Node)); 648 else 649 Body_Node := 650 Make_Subprogram_Body (Loc, 651 Specification => Spec, 652 Declarations => New_List, 653 Handled_Statement_Sequence => 654 Make_Handled_Sequence_Of_Statements (Loc, 655 Statements => New_List (Call_Node))); 656 end if; 657 658 if Nkind (Decl) /= N_Subprogram_Declaration then 659 Rewrite (N, 660 Make_Subprogram_Declaration (Loc, 661 Specification => Specification (N))); 662 end if; 663 664 -- Link the body to the entity whose declaration it completes. If 665 -- the body is analyzed when the renamed entity is frozen, it may 666 -- be necessary to restore the proper scope (see package Exp_Ch13). 667 668 if Nkind (N) = N_Subprogram_Renaming_Declaration 669 and then Present (Corresponding_Spec (N)) 670 then 671 Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N)); 672 else 673 Set_Corresponding_Spec (Body_Node, New_S); 674 end if; 675 676 return Body_Node; 677 end Build_Renamed_Body; 678 679 -------------------------- 680 -- Check_Address_Clause -- 681 -------------------------- 682 683 procedure Check_Address_Clause (E : Entity_Id) is 684 Addr : constant Node_Id := Address_Clause (E); 685 Typ : constant Entity_Id := Etype (E); 686 Decl : Node_Id; 687 Expr : Node_Id; 688 Init : Node_Id; 689 Lhs : Node_Id; 690 Tag_Assign : Node_Id; 691 692 begin 693 if Present (Addr) then 694 695 -- For a deferred constant, the initialization value is on full view 696 697 if Ekind (E) = E_Constant and then Present (Full_View (E)) then 698 Decl := Declaration_Node (Full_View (E)); 699 else 700 Decl := Declaration_Node (E); 701 end if; 702 703 Expr := Expression (Addr); 704 705 if Needs_Constant_Address (Decl, Typ) then 706 Check_Constant_Address_Clause (Expr, E); 707 708 -- Has_Delayed_Freeze was set on E when the address clause was 709 -- analyzed, and must remain set because we want the address 710 -- clause to be elaborated only after any entity it references 711 -- has been elaborated. 712 end if; 713 714 -- If Rep_Clauses are to be ignored, remove address clause from 715 -- list attached to entity, because it may be illegal for gigi, 716 -- for example by breaking order of elaboration. 717 718 if Ignore_Rep_Clauses then 719 declare 720 Rep : Node_Id; 721 722 begin 723 Rep := First_Rep_Item (E); 724 725 if Rep = Addr then 726 Set_First_Rep_Item (E, Next_Rep_Item (Addr)); 727 728 else 729 while Present (Rep) 730 and then Next_Rep_Item (Rep) /= Addr 731 loop 732 Next_Rep_Item (Rep); 733 end loop; 734 end if; 735 736 if Present (Rep) then 737 Set_Next_Rep_Item (Rep, Next_Rep_Item (Addr)); 738 end if; 739 end; 740 741 -- And now remove the address clause 742 743 Kill_Rep_Clause (Addr); 744 745 elsif not Error_Posted (Expr) 746 and then not Needs_Finalization (Typ) 747 then 748 Warn_Overlay (Expr, Typ, Name (Addr)); 749 end if; 750 751 Init := Expression (Decl); 752 753 -- If a variable, or a non-imported constant, overlays a constant 754 -- object and has an initialization value, then the initialization 755 -- may end up writing into read-only memory. Detect the cases of 756 -- statically identical values and remove the initialization. In 757 -- the other cases, give a warning. We will give other warnings 758 -- later for the variable if it is assigned. 759 760 if (Ekind (E) = E_Variable 761 or else (Ekind (E) = E_Constant 762 and then not Is_Imported (E))) 763 and then Overlays_Constant (E) 764 and then Present (Init) 765 then 766 declare 767 O_Ent : Entity_Id; 768 Off : Boolean; 769 770 begin 771 Find_Overlaid_Entity (Addr, O_Ent, Off); 772 773 if Ekind (O_Ent) = E_Constant 774 and then Etype (O_Ent) = Typ 775 and then Present (Constant_Value (O_Ent)) 776 and then Compile_Time_Compare 777 (Init, 778 Constant_Value (O_Ent), 779 Assume_Valid => True) = EQ 780 then 781 Set_No_Initialization (Decl); 782 return; 783 784 elsif Comes_From_Source (Init) 785 and then Address_Clause_Overlay_Warnings 786 then 787 Error_Msg_Sloc := Sloc (Addr); 788 Error_Msg_NE 789 ("??constant& may be modified via address clause#", 790 Decl, O_Ent); 791 end if; 792 end; 793 end if; 794 795 -- Remove side effects from initial expression, except in the case of 796 -- limited build-in-place calls and aggregates, which have their own 797 -- expansion elsewhere. This exception is necessary to avoid copying 798 -- limited objects. 799 800 if Present (Init) 801 and then not Is_Limited_View (Typ) 802 then 803 -- Capture initialization value at point of declaration, and make 804 -- explicit assignment legal, because object may be a constant. 805 806 Remove_Side_Effects (Init); 807 Lhs := New_Occurrence_Of (E, Sloc (Decl)); 808 Set_Assignment_OK (Lhs); 809 810 -- Move initialization to freeze actions, once the object has 811 -- been frozen and the address clause alignment check has been 812 -- performed. 813 814 Append_Freeze_Action (E, 815 Make_Assignment_Statement (Sloc (Decl), 816 Name => Lhs, 817 Expression => Expression (Decl))); 818 819 Set_No_Initialization (Decl); 820 821 -- If the object is tagged, check whether the tag must be 822 -- reassigned explicitly. 823 824 Tag_Assign := Make_Tag_Assignment (Decl); 825 if Present (Tag_Assign) then 826 Append_Freeze_Action (E, Tag_Assign); 827 end if; 828 end if; 829 end if; 830 end Check_Address_Clause; 831 832 ----------------------------- 833 -- Check_Compile_Time_Size -- 834 ----------------------------- 835 836 procedure Check_Compile_Time_Size (T : Entity_Id) is 837 838 procedure Set_Small_Size (T : Entity_Id; S : Uint); 839 -- Sets the compile time known size in the RM_Size field of T, checking 840 -- for a size clause that was given which attempts to give a small size. 841 842 function Size_Known (T : Entity_Id) return Boolean; 843 -- Recursive function that does all the work 844 845 function Static_Discriminated_Components (T : Entity_Id) return Boolean; 846 -- If T is a constrained subtype, its size is not known if any of its 847 -- discriminant constraints is not static and it is not a null record. 848 -- The test is conservative and doesn't check that the components are 849 -- in fact constrained by non-static discriminant values. Could be made 850 -- more precise ??? 851 852 -------------------- 853 -- Set_Small_Size -- 854 -------------------- 855 856 procedure Set_Small_Size (T : Entity_Id; S : Uint) is 857 begin 858 if S > System_Max_Integer_Size then 859 return; 860 861 -- Check for bad size clause given 862 863 elsif Has_Size_Clause (T) then 864 if RM_Size (T) < S then 865 Error_Msg_Uint_1 := S; 866 Error_Msg_NE (Size_Too_Small_Message, Size_Clause (T), T); 867 end if; 868 869 -- Set size if not set already. Do not set it to Uint_0, because in 870 -- some cases (notably array-of-record), the Component_Size is 871 -- No_Uint, which causes S to be Uint_0. Presumably the RM_Size and 872 -- Component_Size will eventually be set correctly by the back end. 873 874 elsif not Known_RM_Size (T) and then S /= Uint_0 then 875 Set_RM_Size (T, S); 876 end if; 877 end Set_Small_Size; 878 879 ---------------- 880 -- Size_Known -- 881 ---------------- 882 883 function Size_Known (T : Entity_Id) return Boolean is 884 Comp : Entity_Id; 885 Ctyp : Entity_Id; 886 887 begin 888 if Size_Known_At_Compile_Time (T) then 889 return True; 890 891 -- Always True for elementary types, even generic formal elementary 892 -- types. We used to return False in the latter case, but the size 893 -- is known at compile time, even in the template, we just do not 894 -- know the exact size but that's not the point of this routine. 895 896 elsif Is_Elementary_Type (T) or else Is_Task_Type (T) then 897 return True; 898 899 -- Array types 900 901 elsif Is_Array_Type (T) then 902 903 -- String literals always have known size, and we can set it 904 905 if Ekind (T) = E_String_Literal_Subtype then 906 if Known_Component_Size (T) then 907 Set_Small_Size 908 (T, Component_Size (T) * String_Literal_Length (T)); 909 910 else 911 -- The following is wrong, but does what previous versions 912 -- did. The Component_Size is unknown for the string in a 913 -- pragma Warnings. 914 Set_Small_Size (T, Uint_0); 915 end if; 916 917 return True; 918 919 -- Unconstrained types never have known at compile time size 920 921 elsif not Is_Constrained (T) then 922 return False; 923 924 -- Don't do any recursion on type with error posted, since we may 925 -- have a malformed type that leads us into a loop. 926 927 elsif Error_Posted (T) then 928 return False; 929 930 -- Otherwise if component size unknown, then array size unknown 931 932 elsif not Size_Known (Component_Type (T)) then 933 return False; 934 end if; 935 936 -- Check for all indexes static, and also compute possible size 937 -- (in case it is not greater than System_Max_Integer_Size and 938 -- thus may be packable). 939 940 declare 941 Index : Entity_Id; 942 Low : Node_Id; 943 High : Node_Id; 944 Size : Uint := Component_Size (T); 945 Dim : Uint; 946 947 begin 948 -- See comment in Set_Small_Size above 949 950 if No (Size) then 951 Size := Uint_0; 952 end if; 953 954 Index := First_Index (T); 955 while Present (Index) loop 956 if Nkind (Index) = N_Range then 957 Get_Index_Bounds (Index, Low, High); 958 959 elsif Error_Posted (Scalar_Range (Etype (Index))) then 960 return False; 961 962 else 963 Low := Type_Low_Bound (Etype (Index)); 964 High := Type_High_Bound (Etype (Index)); 965 end if; 966 967 if not Compile_Time_Known_Value (Low) 968 or else not Compile_Time_Known_Value (High) 969 or else Etype (Index) = Any_Type 970 then 971 return False; 972 973 else 974 Dim := Expr_Value (High) - Expr_Value (Low) + 1; 975 976 if Dim > Uint_0 then 977 Size := Size * Dim; 978 else 979 Size := Uint_0; 980 end if; 981 end if; 982 983 Next_Index (Index); 984 end loop; 985 986 Set_Small_Size (T, Size); 987 return True; 988 end; 989 990 -- For non-generic private types, go to underlying type if present 991 992 elsif Is_Private_Type (T) 993 and then not Is_Generic_Type (T) 994 and then Present (Underlying_Type (T)) 995 then 996 -- Don't do any recursion on type with error posted, since we may 997 -- have a malformed type that leads us into a loop. 998 999 if Error_Posted (T) then 1000 return False; 1001 else 1002 return Size_Known (Underlying_Type (T)); 1003 end if; 1004 1005 -- Record types 1006 1007 elsif Is_Record_Type (T) then 1008 1009 -- A class-wide type is never considered to have a known size 1010 1011 if Is_Class_Wide_Type (T) then 1012 return False; 1013 1014 -- A subtype of a variant record must not have non-static 1015 -- discriminated components. 1016 1017 elsif T /= Base_Type (T) 1018 and then not Static_Discriminated_Components (T) 1019 then 1020 return False; 1021 1022 -- Don't do any recursion on type with error posted, since we may 1023 -- have a malformed type that leads us into a loop. 1024 1025 elsif Error_Posted (T) then 1026 return False; 1027 end if; 1028 1029 -- Now look at the components of the record 1030 1031 declare 1032 -- The following two variables are used to keep track of the 1033 -- size of packed records if we can tell the size of the packed 1034 -- record in the front end. Packed_Size_Known is True if so far 1035 -- we can figure out the size. It is initialized to True for a 1036 -- packed record, unless the record has either discriminants or 1037 -- independent components, or is a strict-alignment type, since 1038 -- it cannot be fully packed in this case. 1039 1040 -- The reason we eliminate the discriminated case is that 1041 -- we don't know the way the back end lays out discriminated 1042 -- packed records. If Packed_Size_Known is True, then 1043 -- Packed_Size is the size in bits so far. 1044 1045 Packed_Size_Known : Boolean := 1046 Is_Packed (T) 1047 and then not Has_Discriminants (T) 1048 and then not Has_Independent_Components (T) 1049 and then not Strict_Alignment (T); 1050 1051 Packed_Size : Uint := Uint_0; 1052 -- Size in bits so far 1053 1054 begin 1055 -- Test for variant part present 1056 1057 if Has_Discriminants (T) 1058 and then Present (Parent (T)) 1059 and then Nkind (Parent (T)) = N_Full_Type_Declaration 1060 and then Nkind (Type_Definition (Parent (T))) = 1061 N_Record_Definition 1062 and then not Null_Present (Type_Definition (Parent (T))) 1063 and then 1064 Present (Variant_Part 1065 (Component_List (Type_Definition (Parent (T))))) 1066 then 1067 -- If variant part is present, and type is unconstrained, 1068 -- then we must have defaulted discriminants, or a size 1069 -- clause must be present for the type, or else the size 1070 -- is definitely not known at compile time. 1071 1072 if not Is_Constrained (T) 1073 and then 1074 No (Discriminant_Default_Value (First_Discriminant (T))) 1075 and then not Known_RM_Size (T) 1076 then 1077 return False; 1078 end if; 1079 end if; 1080 1081 -- Loop through components 1082 1083 Comp := First_Component_Or_Discriminant (T); 1084 while Present (Comp) loop 1085 Ctyp := Etype (Comp); 1086 1087 -- We do not know the packed size if there is a component 1088 -- clause present (we possibly could, but this would only 1089 -- help in the case of a record with partial rep clauses. 1090 -- That's because in the case of full rep clauses, the 1091 -- size gets figured out anyway by a different circuit). 1092 1093 if Present (Component_Clause (Comp)) then 1094 Packed_Size_Known := False; 1095 end if; 1096 1097 -- We do not know the packed size for an independent 1098 -- component or if it is of a strict-alignment type, 1099 -- since packing does not touch these (RM 13.2(7)). 1100 1101 if Is_Independent (Comp) 1102 or else Is_Independent (Ctyp) 1103 or else Strict_Alignment (Ctyp) 1104 then 1105 Packed_Size_Known := False; 1106 end if; 1107 1108 -- We need to identify a component that is an array where 1109 -- the index type is an enumeration type with non-standard 1110 -- representation, and some bound of the type depends on a 1111 -- discriminant. 1112 1113 -- This is because gigi computes the size by doing a 1114 -- substitution of the appropriate discriminant value in 1115 -- the size expression for the base type, and gigi is not 1116 -- clever enough to evaluate the resulting expression (which 1117 -- involves a call to rep_to_pos) at compile time. 1118 1119 -- It would be nice if gigi would either recognize that 1120 -- this expression can be computed at compile time, or 1121 -- alternatively figured out the size from the subtype 1122 -- directly, where all the information is at hand ??? 1123 1124 if Is_Array_Type (Etype (Comp)) 1125 and then Present (Packed_Array_Impl_Type (Etype (Comp))) 1126 then 1127 declare 1128 Ocomp : constant Entity_Id := 1129 Original_Record_Component (Comp); 1130 OCtyp : constant Entity_Id := Etype (Ocomp); 1131 Ind : Node_Id; 1132 Indtyp : Entity_Id; 1133 Lo, Hi : Node_Id; 1134 1135 begin 1136 Ind := First_Index (OCtyp); 1137 while Present (Ind) loop 1138 Indtyp := Etype (Ind); 1139 1140 if Is_Enumeration_Type (Indtyp) 1141 and then Has_Non_Standard_Rep (Indtyp) 1142 then 1143 Lo := Type_Low_Bound (Indtyp); 1144 Hi := Type_High_Bound (Indtyp); 1145 1146 if Is_Entity_Name (Lo) 1147 and then Ekind (Entity (Lo)) = E_Discriminant 1148 then 1149 return False; 1150 1151 elsif Is_Entity_Name (Hi) 1152 and then Ekind (Entity (Hi)) = E_Discriminant 1153 then 1154 return False; 1155 end if; 1156 end if; 1157 1158 Next_Index (Ind); 1159 end loop; 1160 end; 1161 end if; 1162 1163 -- Clearly size of record is not known if the size of one of 1164 -- the components is not known. 1165 1166 if not Size_Known (Ctyp) then 1167 return False; 1168 end if; 1169 1170 -- Accumulate packed size if possible 1171 1172 if Packed_Size_Known then 1173 1174 -- We can deal with elementary types, small packed arrays 1175 -- if the representation is a modular type and also small 1176 -- record types as checked by Set_Small_Size. 1177 1178 if Is_Elementary_Type (Ctyp) 1179 or else (Is_Array_Type (Ctyp) 1180 and then Present 1181 (Packed_Array_Impl_Type (Ctyp)) 1182 and then Is_Modular_Integer_Type 1183 (Packed_Array_Impl_Type (Ctyp))) 1184 or else Is_Record_Type (Ctyp) 1185 then 1186 -- If RM_Size is known and static, then we can keep 1187 -- accumulating the packed size. 1188 1189 if Known_Static_RM_Size (Ctyp) then 1190 1191 Packed_Size := Packed_Size + RM_Size (Ctyp); 1192 1193 -- If we have a field whose RM_Size is not known then 1194 -- we can't figure out the packed size here. 1195 1196 else 1197 Packed_Size_Known := False; 1198 end if; 1199 1200 -- For other types we can't figure out the packed size 1201 1202 else 1203 Packed_Size_Known := False; 1204 end if; 1205 end if; 1206 1207 Next_Component_Or_Discriminant (Comp); 1208 end loop; 1209 1210 if Packed_Size_Known then 1211 Set_Small_Size (T, Packed_Size); 1212 end if; 1213 1214 return True; 1215 end; 1216 1217 -- All other cases, size not known at compile time 1218 1219 else 1220 return False; 1221 end if; 1222 end Size_Known; 1223 1224 ------------------------------------- 1225 -- Static_Discriminated_Components -- 1226 ------------------------------------- 1227 1228 function Static_Discriminated_Components 1229 (T : Entity_Id) return Boolean 1230 is 1231 Constraint : Elmt_Id; 1232 1233 begin 1234 if Has_Discriminants (T) 1235 and then Present (Discriminant_Constraint (T)) 1236 and then Present (First_Component (T)) 1237 then 1238 Constraint := First_Elmt (Discriminant_Constraint (T)); 1239 while Present (Constraint) loop 1240 if not Compile_Time_Known_Value (Node (Constraint)) then 1241 return False; 1242 end if; 1243 1244 Next_Elmt (Constraint); 1245 end loop; 1246 end if; 1247 1248 return True; 1249 end Static_Discriminated_Components; 1250 1251 -- Start of processing for Check_Compile_Time_Size 1252 1253 begin 1254 Set_Size_Known_At_Compile_Time (T, Size_Known (T)); 1255 end Check_Compile_Time_Size; 1256 1257 ----------------------------------- 1258 -- Check_Component_Storage_Order -- 1259 ----------------------------------- 1260 1261 procedure Check_Component_Storage_Order 1262 (Encl_Type : Entity_Id; 1263 Comp : Entity_Id; 1264 ADC : Node_Id; 1265 Comp_ADC_Present : out Boolean) 1266 is 1267 Comp_Base : Entity_Id; 1268 Comp_ADC : Node_Id; 1269 Encl_Base : Entity_Id; 1270 Err_Node : Node_Id; 1271 1272 Component_Aliased : Boolean; 1273 1274 Comp_Byte_Aligned : Boolean := False; 1275 -- Set for the record case, True if Comp is aligned on byte boundaries 1276 -- (in which case it is allowed to have different storage order). 1277 1278 Comp_SSO_Differs : Boolean; 1279 -- Set True when the component is a nested composite, and it does not 1280 -- have the same scalar storage order as Encl_Type. 1281 1282 begin 1283 -- Record case 1284 1285 if Present (Comp) then 1286 Err_Node := Comp; 1287 Comp_Base := Etype (Comp); 1288 1289 if Is_Tag (Comp) then 1290 Comp_Byte_Aligned := True; 1291 Component_Aliased := False; 1292 1293 else 1294 -- If a component clause is present, check if the component starts 1295 -- and ends on byte boundaries. Otherwise conservatively assume it 1296 -- does so only in the case where the record is not packed. 1297 1298 if Present (Component_Clause (Comp)) then 1299 Comp_Byte_Aligned := 1300 Known_Normalized_First_Bit (Comp) 1301 and then 1302 Known_Esize (Comp) 1303 and then 1304 Normalized_First_Bit (Comp) mod System_Storage_Unit = 0 1305 and then 1306 Esize (Comp) mod System_Storage_Unit = 0; 1307 else 1308 Comp_Byte_Aligned := not Is_Packed (Encl_Type); 1309 end if; 1310 1311 Component_Aliased := Is_Aliased (Comp); 1312 end if; 1313 1314 -- Array case 1315 1316 else 1317 Err_Node := Encl_Type; 1318 Comp_Base := Component_Type (Encl_Type); 1319 1320 Component_Aliased := Has_Aliased_Components (Encl_Type); 1321 end if; 1322 1323 -- Note: the Reverse_Storage_Order flag is set on the base type, but 1324 -- the attribute definition clause is attached to the first subtype. 1325 -- Also, if the base type is incomplete or private, go to full view 1326 -- if known 1327 1328 Encl_Base := Base_Type (Encl_Type); 1329 if Present (Underlying_Type (Encl_Base)) then 1330 Encl_Base := Underlying_Type (Encl_Base); 1331 end if; 1332 1333 Comp_Base := Base_Type (Comp_Base); 1334 if Present (Underlying_Type (Comp_Base)) then 1335 Comp_Base := Underlying_Type (Comp_Base); 1336 end if; 1337 1338 Comp_ADC := 1339 Get_Attribute_Definition_Clause 1340 (First_Subtype (Comp_Base), Attribute_Scalar_Storage_Order); 1341 Comp_ADC_Present := Present (Comp_ADC); 1342 1343 -- Case of record or array component: check storage order compatibility. 1344 -- But, if the record has Complex_Representation, then it is treated as 1345 -- a scalar in the back end so the storage order is irrelevant. 1346 1347 if (Is_Record_Type (Comp_Base) 1348 and then not Has_Complex_Representation (Comp_Base)) 1349 or else Is_Array_Type (Comp_Base) 1350 then 1351 Comp_SSO_Differs := 1352 Reverse_Storage_Order (Encl_Base) /= 1353 Reverse_Storage_Order (Comp_Base); 1354 1355 -- Parent and extension must have same storage order 1356 1357 if Present (Comp) and then Chars (Comp) = Name_uParent then 1358 if Comp_SSO_Differs then 1359 Error_Msg_N 1360 ("record extension must have same scalar storage order as " 1361 & "parent", Err_Node); 1362 end if; 1363 1364 -- If component and composite SSO differs, check that component 1365 -- falls on byte boundaries and isn't bit packed. 1366 1367 elsif Comp_SSO_Differs then 1368 1369 -- Component SSO differs from enclosing composite: 1370 1371 -- Reject if composite is a bit-packed array, as it is rewritten 1372 -- into an array of scalars. 1373 1374 if Is_Bit_Packed_Array (Encl_Base) then 1375 Error_Msg_N 1376 ("type of packed array must have same scalar storage order " 1377 & "as component", Err_Node); 1378 1379 -- Reject if not byte aligned 1380 1381 elsif Is_Record_Type (Encl_Base) 1382 and then not Comp_Byte_Aligned 1383 then 1384 if Present (Component_Clause (Comp)) then 1385 Error_Msg_N 1386 ("type of non-byte-aligned component must have same scalar" 1387 & " storage order as enclosing record", Err_Node); 1388 else 1389 Error_Msg_N 1390 ("type of packed component must have same scalar" 1391 & " storage order as enclosing record", Err_Node); 1392 end if; 1393 1394 -- Warn if specified only for the outer composite 1395 1396 elsif Present (ADC) and then No (Comp_ADC) then 1397 Error_Msg_NE 1398 ("scalar storage order specified for & does not apply to " 1399 & "component?", Err_Node, Encl_Base); 1400 end if; 1401 end if; 1402 1403 -- Enclosing type has explicit SSO: non-composite component must not 1404 -- be aliased. 1405 1406 elsif Present (ADC) and then Component_Aliased then 1407 Error_Msg_N 1408 ("aliased component not permitted for type with explicit " 1409 & "Scalar_Storage_Order", Err_Node); 1410 end if; 1411 end Check_Component_Storage_Order; 1412 1413 ----------------------------- 1414 -- Check_Debug_Info_Needed -- 1415 ----------------------------- 1416 1417 procedure Check_Debug_Info_Needed (T : Entity_Id) is 1418 begin 1419 if Debug_Info_Off (T) then 1420 return; 1421 1422 elsif Comes_From_Source (T) 1423 or else Debug_Generated_Code 1424 or else Debug_Flag_VV 1425 or else Needs_Debug_Info (T) 1426 then 1427 Set_Debug_Info_Needed (T); 1428 end if; 1429 end Check_Debug_Info_Needed; 1430 1431 ------------------------------- 1432 -- Check_Expression_Function -- 1433 ------------------------------- 1434 1435 procedure Check_Expression_Function (N : Node_Id; Nam : Entity_Id) is 1436 function Find_Constant (Nod : Node_Id) return Traverse_Result; 1437 -- Function to search for deferred constant 1438 1439 ------------------- 1440 -- Find_Constant -- 1441 ------------------- 1442 1443 function Find_Constant (Nod : Node_Id) return Traverse_Result is 1444 begin 1445 -- When a constant is initialized with the result of a dispatching 1446 -- call, the constant declaration is rewritten as a renaming of the 1447 -- displaced function result. This scenario is not a premature use of 1448 -- a constant even though the Has_Completion flag is not set. 1449 1450 if Is_Entity_Name (Nod) 1451 and then Present (Entity (Nod)) 1452 and then Ekind (Entity (Nod)) = E_Constant 1453 and then Scope (Entity (Nod)) = Current_Scope 1454 and then Nkind (Declaration_Node (Entity (Nod))) = 1455 N_Object_Declaration 1456 and then not Is_Imported (Entity (Nod)) 1457 and then not Has_Completion (Entity (Nod)) 1458 and then not Is_Frozen (Entity (Nod)) 1459 then 1460 Error_Msg_NE 1461 ("premature use of& in call or instance", N, Entity (Nod)); 1462 1463 elsif Nkind (Nod) = N_Attribute_Reference then 1464 Analyze (Prefix (Nod)); 1465 1466 if Is_Entity_Name (Prefix (Nod)) 1467 and then Is_Type (Entity (Prefix (Nod))) 1468 then 1469 Freeze_Before (N, Entity (Prefix (Nod))); 1470 end if; 1471 end if; 1472 1473 return OK; 1474 end Find_Constant; 1475 1476 procedure Check_Deferred is new Traverse_Proc (Find_Constant); 1477 1478 -- Local variables 1479 1480 Decl : Node_Id; 1481 1482 -- Start of processing for Check_Expression_Function 1483 1484 begin 1485 Decl := Original_Node (Unit_Declaration_Node (Nam)); 1486 1487 -- The subprogram body created for the expression function is not 1488 -- itself a freeze point. 1489 1490 if Scope (Nam) = Current_Scope 1491 and then Nkind (Decl) = N_Expression_Function 1492 and then Nkind (N) /= N_Subprogram_Body 1493 then 1494 Check_Deferred (Expression (Decl)); 1495 end if; 1496 end Check_Expression_Function; 1497 1498 -------------------------------- 1499 -- Check_Inherited_Conditions -- 1500 -------------------------------- 1501 1502 procedure Check_Inherited_Conditions 1503 (R : Entity_Id; 1504 Late_Overriding : Boolean := False) 1505 is 1506 Prim_Ops : constant Elist_Id := Primitive_Operations (R); 1507 Decls : List_Id; 1508 Op_Node : Elmt_Id; 1509 Par_Prim : Entity_Id; 1510 Prim : Entity_Id; 1511 Wrapper_Needed : Boolean; 1512 1513 function Build_DTW_Body 1514 (Loc : Source_Ptr; 1515 DTW_Spec : Node_Id; 1516 DTW_Decls : List_Id; 1517 Par_Prim : Entity_Id; 1518 Wrapped_Subp : Entity_Id) return Node_Id; 1519 -- Build the body of the dispatch table wrapper containing the given 1520 -- spec and declarations; the call to the wrapped subprogram includes 1521 -- the proper type conversion. 1522 1523 function Build_DTW_Spec (Par_Prim : Entity_Id) return Node_Id; 1524 -- Build the spec of the dispatch table wrapper 1525 1526 procedure Build_Inherited_Condition_Pragmas 1527 (Subp : Entity_Id; 1528 Wrapper_Needed : out Boolean); 1529 -- Build corresponding pragmas for an operation whose ancestor has 1530 -- class-wide pre/postconditions. If the operation is inherited then 1531 -- Wrapper_Needed is returned True to force the creation of a wrapper 1532 -- for the inherited operation. If the ancestor is being overridden, 1533 -- the pragmas are constructed only to verify their legality, in case 1534 -- they contain calls to other primitives that may have been overridden. 1535 1536 function Needs_Wrapper 1537 (Class_Cond : Node_Id; 1538 Subp : Entity_Id; 1539 Par_Subp : Entity_Id) return Boolean; 1540 -- Checks whether the dispatch-table wrapper (DTW) for Subp must be 1541 -- built to evaluate the given class-wide condition. 1542 1543 -------------------- 1544 -- Build_DTW_Body -- 1545 -------------------- 1546 1547 function Build_DTW_Body 1548 (Loc : Source_Ptr; 1549 DTW_Spec : Node_Id; 1550 DTW_Decls : List_Id; 1551 Par_Prim : Entity_Id; 1552 Wrapped_Subp : Entity_Id) return Node_Id 1553 is 1554 Par_Typ : constant Entity_Id := Find_Dispatching_Type (Par_Prim); 1555 Actuals : constant List_Id := Empty_List; 1556 Call : Node_Id; 1557 Formal : Entity_Id := First_Formal (Par_Prim); 1558 New_F_Spec : Entity_Id := First (Parameter_Specifications (DTW_Spec)); 1559 New_Formal : Entity_Id; 1560 1561 begin 1562 -- Build parameter association for call to wrapped subprogram 1563 1564 while Present (Formal) loop 1565 New_Formal := Defining_Identifier (New_F_Spec); 1566 1567 -- If the controlling argument is inherited, add conversion to 1568 -- parent type for the call. 1569 1570 if Etype (Formal) = Par_Typ 1571 and then Is_Controlling_Formal (Formal) 1572 then 1573 Append_To (Actuals, 1574 Make_Type_Conversion (Loc, 1575 New_Occurrence_Of (Par_Typ, Loc), 1576 New_Occurrence_Of (New_Formal, Loc))); 1577 else 1578 Append_To (Actuals, New_Occurrence_Of (New_Formal, Loc)); 1579 end if; 1580 1581 Next_Formal (Formal); 1582 Next (New_F_Spec); 1583 end loop; 1584 1585 if Ekind (Wrapped_Subp) = E_Procedure then 1586 Call := 1587 Make_Procedure_Call_Statement (Loc, 1588 Name => New_Occurrence_Of (Wrapped_Subp, Loc), 1589 Parameter_Associations => Actuals); 1590 else 1591 Call := 1592 Make_Simple_Return_Statement (Loc, 1593 Expression => 1594 Make_Function_Call (Loc, 1595 Name => New_Occurrence_Of (Wrapped_Subp, Loc), 1596 Parameter_Associations => Actuals)); 1597 end if; 1598 1599 return 1600 Make_Subprogram_Body (Loc, 1601 Specification => Copy_Subprogram_Spec (DTW_Spec), 1602 Declarations => DTW_Decls, 1603 Handled_Statement_Sequence => 1604 Make_Handled_Sequence_Of_Statements (Loc, 1605 Statements => New_List (Call), 1606 End_Label => Make_Identifier (Loc, 1607 Chars (Defining_Entity (DTW_Spec))))); 1608 end Build_DTW_Body; 1609 1610 -------------------- 1611 -- Build_DTW_Spec -- 1612 -------------------- 1613 1614 function Build_DTW_Spec (Par_Prim : Entity_Id) return Node_Id is 1615 DTW_Id : Entity_Id; 1616 DTW_Spec : Node_Id; 1617 1618 begin 1619 DTW_Spec := Build_Overriding_Spec (Par_Prim, R); 1620 DTW_Id := Defining_Entity (DTW_Spec); 1621 1622 -- Add minimal decoration of fields 1623 1624 Mutate_Ekind (DTW_Id, Ekind (Par_Prim)); 1625 Set_LSP_Subprogram (DTW_Id, Par_Prim); 1626 Set_Is_Dispatch_Table_Wrapper (DTW_Id); 1627 Set_Is_Wrapper (DTW_Id); 1628 1629 -- The DTW wrapper is never a null procedure 1630 1631 if Nkind (DTW_Spec) = N_Procedure_Specification then 1632 Set_Null_Present (DTW_Spec, False); 1633 end if; 1634 1635 return DTW_Spec; 1636 end Build_DTW_Spec; 1637 1638 --------------------------------------- 1639 -- Build_Inherited_Condition_Pragmas -- 1640 --------------------------------------- 1641 1642 procedure Build_Inherited_Condition_Pragmas 1643 (Subp : Entity_Id; 1644 Wrapper_Needed : out Boolean) 1645 is 1646 Class_Pre : constant Node_Id := 1647 Class_Preconditions (Ultimate_Alias (Subp)); 1648 Class_Post : Node_Id := Class_Postconditions (Par_Prim); 1649 A_Post : Node_Id; 1650 New_Prag : Node_Id; 1651 1652 begin 1653 Wrapper_Needed := False; 1654 1655 if No (Class_Pre) and then No (Class_Post) then 1656 return; 1657 end if; 1658 1659 -- For class-wide preconditions we just evaluate whether the wrapper 1660 -- is needed; there is no need to build the pragma since the check 1661 -- is performed on the caller side. 1662 1663 if Present (Class_Pre) 1664 and then Needs_Wrapper (Class_Pre, Subp, Par_Prim) 1665 then 1666 Wrapper_Needed := True; 1667 end if; 1668 1669 -- For class-wide postconditions we evaluate whether the wrapper is 1670 -- needed and we build the class-wide postcondition pragma to install 1671 -- it in the wrapper. 1672 1673 if Present (Class_Post) 1674 and then Needs_Wrapper (Class_Post, Subp, Par_Prim) 1675 then 1676 Wrapper_Needed := True; 1677 1678 -- Update the class-wide postcondition 1679 1680 Class_Post := New_Copy_Tree (Class_Post); 1681 Build_Class_Wide_Expression 1682 (Pragma_Or_Expr => Class_Post, 1683 Subp => Subp, 1684 Par_Subp => Par_Prim, 1685 Adjust_Sloc => False); 1686 1687 -- Install the updated class-wide postcondition in a copy of the 1688 -- pragma postcondition defined for the nearest ancestor. 1689 1690 A_Post := Get_Class_Wide_Pragma (Par_Prim, 1691 Pragma_Postcondition); 1692 1693 if No (A_Post) then 1694 declare 1695 Subps : constant Subprogram_List := 1696 Inherited_Subprograms (Subp); 1697 begin 1698 for Index in Subps'Range loop 1699 A_Post := Get_Class_Wide_Pragma (Subps (Index), 1700 Pragma_Postcondition); 1701 exit when Present (A_Post); 1702 end loop; 1703 end; 1704 end if; 1705 1706 New_Prag := New_Copy_Tree (A_Post); 1707 Rewrite 1708 (Expression (First (Pragma_Argument_Associations (New_Prag))), 1709 Class_Post); 1710 Append (New_Prag, Decls); 1711 end if; 1712 end Build_Inherited_Condition_Pragmas; 1713 1714 ------------------- 1715 -- Needs_Wrapper -- 1716 ------------------- 1717 1718 function Needs_Wrapper 1719 (Class_Cond : Node_Id; 1720 Subp : Entity_Id; 1721 Par_Subp : Entity_Id) return Boolean 1722 is 1723 Result : Boolean := False; 1724 1725 function Check_Entity (N : Node_Id) return Traverse_Result; 1726 -- Check calls to overridden primitives 1727 1728 -------------------- 1729 -- Replace_Entity -- 1730 -------------------- 1731 1732 function Check_Entity (N : Node_Id) return Traverse_Result is 1733 New_E : Entity_Id; 1734 1735 begin 1736 if Nkind (N) = N_Identifier 1737 and then Present (Entity (N)) 1738 and then 1739 (Is_Formal (Entity (N)) or else Is_Subprogram (Entity (N))) 1740 and then 1741 (Nkind (Parent (N)) /= N_Attribute_Reference 1742 or else Attribute_Name (Parent (N)) /= Name_Class) 1743 then 1744 -- The check does not apply to dispatching calls within the 1745 -- condition, but only to calls whose static tag is that of 1746 -- the parent type. 1747 1748 if Is_Subprogram (Entity (N)) 1749 and then Nkind (Parent (N)) = N_Function_Call 1750 and then Present (Controlling_Argument (Parent (N))) 1751 then 1752 return OK; 1753 end if; 1754 1755 -- Determine whether entity has a renaming 1756 1757 New_E := Get_Mapped_Entity (Entity (N)); 1758 1759 -- If the entity is an overridden primitive and we are not 1760 -- in GNATprove mode, we must build a wrapper for the current 1761 -- inherited operation. If the reference is the prefix of an 1762 -- attribute such as 'Result (or others ???) there is no need 1763 -- for a wrapper: the condition is just rewritten in terms of 1764 -- the inherited subprogram. 1765 1766 if Present (New_E) 1767 and then Comes_From_Source (New_E) 1768 and then Is_Subprogram (New_E) 1769 and then Nkind (Parent (N)) /= N_Attribute_Reference 1770 and then not GNATprove_Mode 1771 then 1772 Result := True; 1773 return Abandon; 1774 end if; 1775 end if; 1776 1777 return OK; 1778 end Check_Entity; 1779 1780 procedure Check_Condition_Entities is 1781 new Traverse_Proc (Check_Entity); 1782 1783 -- Start of processing for Needs_Wrapper 1784 1785 begin 1786 Update_Primitives_Mapping (Par_Subp, Subp); 1787 1788 Map_Formals (Par_Subp, Subp); 1789 Check_Condition_Entities (Class_Cond); 1790 1791 return Result; 1792 end Needs_Wrapper; 1793 1794 Ifaces_List : Elist_Id := No_Elist; 1795 Ifaces_Listed : Boolean := False; 1796 -- Cache the list of interface operations inherited by R 1797 1798 -- Start of processing for Check_Inherited_Conditions 1799 1800 begin 1801 if Late_Overriding then 1802 Op_Node := First_Elmt (Prim_Ops); 1803 while Present (Op_Node) loop 1804 Prim := Node (Op_Node); 1805 1806 -- Map the overridden primitive to the overriding one 1807 1808 if Present (Overridden_Operation (Prim)) 1809 and then Comes_From_Source (Prim) 1810 then 1811 Par_Prim := Overridden_Operation (Prim); 1812 Update_Primitives_Mapping (Par_Prim, Prim); 1813 1814 -- Force discarding previous mappings of its formals 1815 1816 Map_Formals (Par_Prim, Prim, Force_Update => True); 1817 end if; 1818 1819 Next_Elmt (Op_Node); 1820 end loop; 1821 end if; 1822 1823 -- Perform validity checks on the inherited conditions of overriding 1824 -- operations, for conformance with LSP, and apply SPARK-specific 1825 -- restrictions on inherited conditions. 1826 1827 Op_Node := First_Elmt (Prim_Ops); 1828 while Present (Op_Node) loop 1829 Prim := Node (Op_Node); 1830 1831 Par_Prim := Overridden_Operation (Prim); 1832 if Present (Par_Prim) 1833 and then Comes_From_Source (Prim) 1834 then 1835 -- When the primitive is an LSP wrapper we climb to the parent 1836 -- primitive that has the inherited contract. 1837 1838 if Is_Wrapper (Par_Prim) 1839 and then Present (LSP_Subprogram (Par_Prim)) 1840 then 1841 Par_Prim := LSP_Subprogram (Par_Prim); 1842 end if; 1843 1844 -- Check that overrider and overridden operations have 1845 -- the same strub mode. 1846 1847 Check_Same_Strub_Mode (Prim, Par_Prim); 1848 1849 -- Analyze the contract items of the overridden operation, before 1850 -- they are rewritten as pragmas. 1851 1852 Analyze_Entry_Or_Subprogram_Contract (Par_Prim); 1853 1854 -- In GNATprove mode this is where we can collect the inherited 1855 -- conditions, because we do not create the Check pragmas that 1856 -- normally convey the modified class-wide conditions on 1857 -- overriding operations. 1858 1859 if GNATprove_Mode then 1860 Collect_Inherited_Class_Wide_Conditions (Prim); 1861 end if; 1862 end if; 1863 1864 -- Go over operations inherited from interfaces and check 1865 -- them for strub mode compatibility as well. 1866 1867 if Has_Interfaces (R) 1868 and then Is_Dispatching_Operation (Prim) 1869 and then Find_Dispatching_Type (Prim) = R 1870 then 1871 declare 1872 Elmt : Elmt_Id; 1873 Iface_Elmt : Elmt_Id; 1874 Iface : Entity_Id; 1875 Iface_Prim : Entity_Id; 1876 1877 begin 1878 -- Collect the interfaces only once. We haven't 1879 -- finished freezing yet, so we can't use the faster 1880 -- search from Sem_Disp.Covered_Interface_Primitives. 1881 1882 if not Ifaces_Listed then 1883 Collect_Interfaces (R, Ifaces_List); 1884 Ifaces_Listed := True; 1885 end if; 1886 1887 Iface_Elmt := First_Elmt (Ifaces_List); 1888 while Present (Iface_Elmt) loop 1889 Iface := Node (Iface_Elmt); 1890 1891 Elmt := First_Elmt (Primitive_Operations (Iface)); 1892 while Present (Elmt) loop 1893 Iface_Prim := Node (Elmt); 1894 1895 if Iface_Prim /= Par_Prim 1896 and then Chars (Iface_Prim) = Chars (Prim) 1897 and then Comes_From_Source (Iface_Prim) 1898 and then (Is_Interface_Conformant 1899 (R, Iface_Prim, Prim)) 1900 then 1901 Check_Same_Strub_Mode (Prim, Iface_Prim); 1902 end if; 1903 1904 Next_Elmt (Elmt); 1905 end loop; 1906 1907 Next_Elmt (Iface_Elmt); 1908 end loop; 1909 end; 1910 end if; 1911 1912 Next_Elmt (Op_Node); 1913 end loop; 1914 1915 -- Now examine the inherited operations to check whether they require 1916 -- a wrapper to handle inherited conditions that call other primitives, 1917 -- so that LSP can be verified/enforced. 1918 1919 Op_Node := First_Elmt (Prim_Ops); 1920 1921 while Present (Op_Node) loop 1922 Decls := Empty_List; 1923 Prim := Node (Op_Node); 1924 Wrapper_Needed := False; 1925 1926 -- Skip internal entities built for mapping interface primitives 1927 1928 if not Comes_From_Source (Prim) 1929 and then Present (Alias (Prim)) 1930 and then No (Interface_Alias (Prim)) 1931 then 1932 Par_Prim := Ultimate_Alias (Prim); 1933 1934 -- When the primitive is an LSP wrapper we climb to the parent 1935 -- primitive that has the inherited contract. 1936 1937 if Is_Wrapper (Par_Prim) 1938 and then Present (LSP_Subprogram (Par_Prim)) 1939 then 1940 Par_Prim := LSP_Subprogram (Par_Prim); 1941 end if; 1942 1943 -- Analyze the contract items of the parent operation, and 1944 -- determine whether a wrapper is needed. This is determined 1945 -- when the condition is rewritten in sem_prag, using the 1946 -- mapping between overridden and overriding operations built 1947 -- in the loop above. 1948 1949 Analyze_Entry_Or_Subprogram_Contract (Par_Prim); 1950 Build_Inherited_Condition_Pragmas (Prim, Wrapper_Needed); 1951 end if; 1952 1953 if Wrapper_Needed 1954 and then not Is_Abstract_Subprogram (Par_Prim) 1955 and then Expander_Active 1956 then 1957 -- Build the dispatch-table wrapper (DTW). The support for 1958 -- AI12-0195 relies on two kind of wrappers: one for indirect 1959 -- calls (also used for AI12-0220), and one for putting in the 1960 -- dispatch table: 1961 -- 1962 -- 1) "indirect-call wrapper" (ICW) is needed anytime there are 1963 -- class-wide preconditions. Prim'Access will point directly 1964 -- at the ICW if any, or at the "pristine" body if Prim has 1965 -- no class-wide preconditions. 1966 -- 1967 -- 2) "dispatch-table wrapper" (DTW) is needed anytime the class 1968 -- wide preconditions *or* the class-wide postconditions are 1969 -- affected by overriding. 1970 -- 1971 -- The DTW holds a single statement that is a single call where 1972 -- the controlling actuals are conversions to the corresponding 1973 -- type in the parent primitive. If the primitive is a function 1974 -- the statement is a return statement with a call. 1975 1976 declare 1977 Alias_Id : constant Entity_Id := Ultimate_Alias (Prim); 1978 Loc : constant Source_Ptr := Sloc (R); 1979 DTW_Body : Node_Id; 1980 DTW_Decl : Node_Id; 1981 DTW_Id : Entity_Id; 1982 DTW_Spec : Node_Id; 1983 1984 begin 1985 -- The wrapper must be analyzed in the scope of its wrapped 1986 -- primitive (to ensure its correct decoration). 1987 1988 Push_Scope (Scope (Prim)); 1989 1990 DTW_Spec := Build_DTW_Spec (Par_Prim); 1991 DTW_Id := Defining_Entity (DTW_Spec); 1992 DTW_Decl := Make_Subprogram_Declaration (Loc, 1993 Specification => DTW_Spec); 1994 1995 -- For inherited class-wide preconditions the DTW wrapper 1996 -- reuses the ICW of the parent (which checks the parent 1997 -- interpretation of the class-wide preconditions); the 1998 -- interpretation of the class-wide preconditions for the 1999 -- inherited subprogram is checked at the caller side. 2000 2001 -- When the subprogram inherits class-wide postconditions 2002 -- the DTW also checks the interpretation of the class-wide 2003 -- postconditions for the inherited subprogram, and the body 2004 -- of the parent checks its interpretation of the parent for 2005 -- the class-wide postconditions. 2006 2007 -- procedure Prim (F1 : T1; ...) is 2008 -- [ pragma Check (Postcondition, Expr); ] 2009 -- begin 2010 -- Par_Prim_ICW (Par_Type (F1), ...); 2011 -- end; 2012 2013 if Present (Indirect_Call_Wrapper (Par_Prim)) then 2014 DTW_Body := 2015 Build_DTW_Body (Loc, 2016 DTW_Spec => DTW_Spec, 2017 DTW_Decls => Decls, 2018 Par_Prim => Par_Prim, 2019 Wrapped_Subp => Indirect_Call_Wrapper (Par_Prim)); 2020 2021 -- For subprograms that only inherit class-wide postconditions 2022 -- the DTW wrapper calls the parent primitive (which on its 2023 -- body checks the interpretation of the class-wide post- 2024 -- conditions for the parent subprogram), and the DTW checks 2025 -- the interpretation of the class-wide postconditions for the 2026 -- inherited subprogram. 2027 2028 -- procedure Prim (F1 : T1; ...) is 2029 -- pragma Check (Postcondition, Expr); 2030 -- begin 2031 -- Par_Prim (Par_Type (F1), ...); 2032 -- end; 2033 2034 else 2035 DTW_Body := 2036 Build_DTW_Body (Loc, 2037 DTW_Spec => DTW_Spec, 2038 DTW_Decls => Decls, 2039 Par_Prim => Par_Prim, 2040 Wrapped_Subp => Par_Prim); 2041 end if; 2042 2043 -- Insert the declaration of the wrapper before the freezing 2044 -- node of the record type declaration to ensure that it will 2045 -- override the internal primitive built by Derive_Subprogram. 2046 2047 if Late_Overriding then 2048 Ensure_Freeze_Node (R); 2049 Insert_Before_And_Analyze (Freeze_Node (R), DTW_Decl); 2050 else 2051 Append_Freeze_Action (R, DTW_Decl); 2052 end if; 2053 2054 Analyze (DTW_Decl); 2055 2056 -- Insert the body of the wrapper in the freeze actions of 2057 -- its record type declaration to ensure that it is placed 2058 -- in the scope of its declaration but not too early to cause 2059 -- premature freezing of other entities. 2060 2061 Append_Freeze_Action (R, DTW_Body); 2062 Analyze (DTW_Body); 2063 2064 -- Ensure correct decoration 2065 2066 pragma Assert (Is_Dispatching_Operation (DTW_Id)); 2067 pragma Assert (Present (Overridden_Operation (DTW_Id))); 2068 pragma Assert (Overridden_Operation (DTW_Id) = Alias_Id); 2069 2070 -- Inherit dispatch table slot 2071 2072 Set_DTC_Entity_Value (R, DTW_Id); 2073 Set_DT_Position (DTW_Id, DT_Position (Alias_Id)); 2074 2075 -- Register the wrapper in the dispatch table 2076 2077 if Late_Overriding 2078 and then not Building_Static_DT (R) 2079 then 2080 Insert_List_After_And_Analyze (Freeze_Node (R), 2081 Register_Primitive (Loc, DTW_Id)); 2082 end if; 2083 2084 -- Build the helper and ICW for the DTW 2085 2086 if Present (Indirect_Call_Wrapper (Par_Prim)) then 2087 declare 2088 CW_Subp : Entity_Id; 2089 Decl_N : Node_Id; 2090 Body_N : Node_Id; 2091 2092 begin 2093 Merge_Class_Conditions (DTW_Id); 2094 Make_Class_Precondition_Subps (DTW_Id, 2095 Late_Overriding => Late_Overriding); 2096 2097 CW_Subp := Static_Call_Helper (DTW_Id); 2098 Decl_N := Unit_Declaration_Node (CW_Subp); 2099 Analyze (Decl_N); 2100 2101 -- If the DTW was built for a late-overriding primitive 2102 -- its body must be analyzed now (since the tagged type 2103 -- is already frozen). 2104 2105 if Late_Overriding then 2106 Body_N := 2107 Unit_Declaration_Node 2108 (Corresponding_Body (Decl_N)); 2109 Analyze (Body_N); 2110 end if; 2111 end; 2112 end if; 2113 2114 Pop_Scope; 2115 end; 2116 end if; 2117 2118 Next_Elmt (Op_Node); 2119 end loop; 2120 end Check_Inherited_Conditions; 2121 2122 ---------------------------- 2123 -- Check_Strict_Alignment -- 2124 ---------------------------- 2125 2126 procedure Check_Strict_Alignment (E : Entity_Id) is 2127 Comp : Entity_Id; 2128 2129 begin 2130 -- Bit-packed array types do not require strict alignment, even if they 2131 -- are by-reference types, because they are accessed in a special way. 2132 2133 if Is_By_Reference_Type (E) and then not Is_Bit_Packed_Array (E) then 2134 Set_Strict_Alignment (E); 2135 2136 elsif Is_Array_Type (E) then 2137 Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E))); 2138 2139 -- ??? AI12-001: Any component of a packed type that contains an 2140 -- aliased part must be aligned according to the alignment of its 2141 -- subtype (RM 13.2(7)). This means that the following test: 2142 2143 -- if Has_Aliased_Components (E) then 2144 -- Set_Strict_Alignment (E); 2145 -- end if; 2146 2147 -- should be implemented here. Unfortunately it would break Florist, 2148 -- which has the bad habit of overaligning all the types it declares 2149 -- on 32-bit platforms. Other legacy codebases could also be affected 2150 -- because this check has historically been missing in GNAT. 2151 2152 elsif Is_Record_Type (E) then 2153 Comp := First_Component (E); 2154 while Present (Comp) loop 2155 if not Is_Type (Comp) 2156 and then (Is_Aliased (Comp) 2157 or else Strict_Alignment (Etype (Comp))) 2158 then 2159 Set_Strict_Alignment (E); 2160 return; 2161 end if; 2162 2163 Next_Component (Comp); 2164 end loop; 2165 end if; 2166 end Check_Strict_Alignment; 2167 2168 ------------------------- 2169 -- Check_Unsigned_Type -- 2170 ------------------------- 2171 2172 procedure Check_Unsigned_Type (E : Entity_Id) is 2173 Ancestor : Entity_Id; 2174 Lo_Bound : Node_Id; 2175 Btyp : Entity_Id; 2176 2177 begin 2178 if not Is_Discrete_Or_Fixed_Point_Type (E) then 2179 return; 2180 end if; 2181 2182 -- Do not attempt to analyze case where range was in error 2183 2184 if No (Scalar_Range (E)) or else Error_Posted (Scalar_Range (E)) then 2185 return; 2186 end if; 2187 2188 -- The situation that is nontrivial is something like: 2189 2190 -- subtype x1 is integer range -10 .. +10; 2191 -- subtype x2 is x1 range 0 .. V1; 2192 -- subtype x3 is x2 range V2 .. V3; 2193 -- subtype x4 is x3 range V4 .. V5; 2194 2195 -- where Vn are variables. Here the base type is signed, but we still 2196 -- know that x4 is unsigned because of the lower bound of x2. 2197 2198 -- The only way to deal with this is to look up the ancestor chain 2199 2200 Ancestor := E; 2201 loop 2202 if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then 2203 return; 2204 end if; 2205 2206 Lo_Bound := Type_Low_Bound (Ancestor); 2207 2208 if Compile_Time_Known_Value (Lo_Bound) then 2209 if Expr_Rep_Value (Lo_Bound) >= 0 then 2210 Set_Is_Unsigned_Type (E, True); 2211 end if; 2212 2213 return; 2214 2215 else 2216 Ancestor := Ancestor_Subtype (Ancestor); 2217 2218 -- If no ancestor had a static lower bound, go to base type 2219 2220 if No (Ancestor) then 2221 2222 -- Note: the reason we still check for a compile time known 2223 -- value for the base type is that at least in the case of 2224 -- generic formals, we can have bounds that fail this test, 2225 -- and there may be other cases in error situations. 2226 2227 Btyp := Base_Type (E); 2228 2229 if Btyp = Any_Type or else Etype (Btyp) = Any_Type then 2230 return; 2231 end if; 2232 2233 Lo_Bound := Type_Low_Bound (Base_Type (E)); 2234 2235 if Compile_Time_Known_Value (Lo_Bound) 2236 and then Expr_Rep_Value (Lo_Bound) >= 0 2237 then 2238 Set_Is_Unsigned_Type (E, True); 2239 end if; 2240 2241 return; 2242 end if; 2243 end if; 2244 end loop; 2245 end Check_Unsigned_Type; 2246 2247 ------------------------------ 2248 -- Is_Full_Access_Aggregate -- 2249 ------------------------------ 2250 2251 function Is_Full_Access_Aggregate (N : Node_Id) return Boolean is 2252 Loc : constant Source_Ptr := Sloc (N); 2253 New_N : Node_Id; 2254 Par : Node_Id; 2255 Temp : Entity_Id; 2256 Typ : Entity_Id; 2257 2258 begin 2259 Par := Parent (N); 2260 2261 -- Array may be qualified, so find outer context 2262 2263 if Nkind (Par) = N_Qualified_Expression then 2264 Par := Parent (Par); 2265 end if; 2266 2267 if not Comes_From_Source (Par) then 2268 return False; 2269 end if; 2270 2271 case Nkind (Par) is 2272 when N_Assignment_Statement => 2273 Typ := Etype (Name (Par)); 2274 2275 if not Is_Full_Access (Typ) 2276 and then not Is_Full_Access_Object (Name (Par)) 2277 then 2278 return False; 2279 end if; 2280 2281 when N_Object_Declaration => 2282 Typ := Etype (Defining_Identifier (Par)); 2283 2284 if not Is_Full_Access (Typ) 2285 and then not Is_Full_Access (Defining_Identifier (Par)) 2286 then 2287 return False; 2288 end if; 2289 2290 when others => 2291 return False; 2292 end case; 2293 2294 Temp := Make_Temporary (Loc, 'T', N); 2295 New_N := 2296 Make_Object_Declaration (Loc, 2297 Defining_Identifier => Temp, 2298 Constant_Present => True, 2299 Object_Definition => New_Occurrence_Of (Typ, Loc), 2300 Expression => Relocate_Node (N)); 2301 Insert_Before (Par, New_N); 2302 Analyze (New_N); 2303 2304 Set_Expression (Par, New_Occurrence_Of (Temp, Loc)); 2305 return True; 2306 end Is_Full_Access_Aggregate; 2307 2308 ----------------------------------------------- 2309 -- Explode_Initialization_Compound_Statement -- 2310 ----------------------------------------------- 2311 2312 procedure Explode_Initialization_Compound_Statement (E : Entity_Id) is 2313 Init_Stmts : constant Node_Id := Initialization_Statements (E); 2314 2315 begin 2316 if Present (Init_Stmts) 2317 and then Nkind (Init_Stmts) = N_Compound_Statement 2318 then 2319 Insert_List_Before (Init_Stmts, Actions (Init_Stmts)); 2320 2321 -- Note that we rewrite Init_Stmts into a NULL statement, rather than 2322 -- just removing it, because Freeze_All may rely on this particular 2323 -- Node_Id still being present in the enclosing list to know where to 2324 -- stop freezing. 2325 2326 Rewrite (Init_Stmts, Make_Null_Statement (Sloc (Init_Stmts))); 2327 2328 Set_Initialization_Statements (E, Empty); 2329 end if; 2330 end Explode_Initialization_Compound_Statement; 2331 2332 ---------------- 2333 -- Freeze_All -- 2334 ---------------- 2335 2336 -- Note: the easy coding for this procedure would be to just build a 2337 -- single list of freeze nodes and then insert them and analyze them 2338 -- all at once. This won't work, because the analysis of earlier freeze 2339 -- nodes may recursively freeze types which would otherwise appear later 2340 -- on in the freeze list. So we must analyze and expand the freeze nodes 2341 -- as they are generated. 2342 2343 procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is 2344 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id); 2345 -- This is the internal recursive routine that does freezing of entities 2346 -- (but NOT the analysis of default expressions, which should not be 2347 -- recursive, we don't want to analyze those till we are sure that ALL 2348 -- the types are frozen). 2349 2350 -------------------- 2351 -- Freeze_All_Ent -- 2352 -------------------- 2353 2354 procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is 2355 E : Entity_Id; 2356 Flist : List_Id; 2357 Lastn : Node_Id; 2358 2359 procedure Process_Flist; 2360 -- If freeze nodes are present, insert and analyze, and reset cursor 2361 -- for next insertion. 2362 2363 ------------------- 2364 -- Process_Flist -- 2365 ------------------- 2366 2367 procedure Process_Flist is 2368 begin 2369 if Is_Non_Empty_List (Flist) then 2370 Lastn := Next (After); 2371 Insert_List_After_And_Analyze (After, Flist); 2372 2373 if Present (Lastn) then 2374 After := Prev (Lastn); 2375 else 2376 After := Last (List_Containing (After)); 2377 end if; 2378 end if; 2379 end Process_Flist; 2380 2381 -- Start of processing for Freeze_All_Ent 2382 2383 begin 2384 E := From; 2385 while Present (E) loop 2386 2387 -- If the entity is an inner package which is not a package 2388 -- renaming, then its entities must be frozen at this point. Note 2389 -- that such entities do NOT get frozen at the end of the nested 2390 -- package itself (only library packages freeze). 2391 2392 -- Same is true for task declarations, where anonymous records 2393 -- created for entry parameters must be frozen. 2394 2395 if Ekind (E) = E_Package 2396 and then No (Renamed_Entity (E)) 2397 and then not Is_Child_Unit (E) 2398 and then not Is_Frozen (E) 2399 then 2400 Push_Scope (E); 2401 2402 Install_Visible_Declarations (E); 2403 Install_Private_Declarations (E); 2404 Freeze_All (First_Entity (E), After); 2405 2406 End_Package_Scope (E); 2407 2408 if Is_Generic_Instance (E) 2409 and then Has_Delayed_Freeze (E) 2410 then 2411 Set_Has_Delayed_Freeze (E, False); 2412 Expand_N_Package_Declaration (Unit_Declaration_Node (E)); 2413 end if; 2414 2415 elsif Ekind (E) in Task_Kind 2416 and then Nkind (Parent (E)) in 2417 N_Single_Task_Declaration | N_Task_Type_Declaration 2418 then 2419 Push_Scope (E); 2420 Freeze_All (First_Entity (E), After); 2421 End_Scope; 2422 2423 -- For a derived tagged type, we must ensure that all the 2424 -- primitive operations of the parent have been frozen, so that 2425 -- their addresses will be in the parent's dispatch table at the 2426 -- point it is inherited. 2427 2428 elsif Ekind (E) = E_Record_Type 2429 and then Is_Tagged_Type (E) 2430 and then Is_Tagged_Type (Etype (E)) 2431 and then Is_Derived_Type (E) 2432 then 2433 declare 2434 Prim_List : constant Elist_Id := 2435 Primitive_Operations (Etype (E)); 2436 2437 Prim : Elmt_Id; 2438 Subp : Entity_Id; 2439 2440 begin 2441 Prim := First_Elmt (Prim_List); 2442 while Present (Prim) loop 2443 Subp := Node (Prim); 2444 2445 if Comes_From_Source (Subp) 2446 and then not Is_Frozen (Subp) 2447 then 2448 Flist := Freeze_Entity (Subp, After); 2449 Process_Flist; 2450 end if; 2451 2452 Next_Elmt (Prim); 2453 end loop; 2454 end; 2455 end if; 2456 2457 if not Is_Frozen (E) then 2458 Flist := Freeze_Entity (E, After); 2459 Process_Flist; 2460 2461 -- If already frozen, and there are delayed aspects, this is where 2462 -- we do the visibility check for these aspects (see Sem_Ch13 spec 2463 -- for a description of how we handle aspect visibility). 2464 2465 elsif Has_Delayed_Aspects (E) then 2466 declare 2467 Ritem : Node_Id; 2468 2469 begin 2470 Ritem := First_Rep_Item (E); 2471 while Present (Ritem) loop 2472 if Nkind (Ritem) = N_Aspect_Specification 2473 and then Entity (Ritem) = E 2474 and then Is_Delayed_Aspect (Ritem) 2475 then 2476 Check_Aspect_At_End_Of_Declarations (Ritem); 2477 end if; 2478 2479 Next_Rep_Item (Ritem); 2480 end loop; 2481 end; 2482 end if; 2483 2484 -- If an incomplete type is still not frozen, this may be a 2485 -- premature freezing because of a body declaration that follows. 2486 -- Indicate where the freezing took place. Freezing will happen 2487 -- if the body comes from source, but not if it is internally 2488 -- generated, for example as the body of a type invariant. 2489 2490 -- If the freezing is caused by the end of the current declarative 2491 -- part, it is a Taft Amendment type, and there is no error. 2492 2493 if not Is_Frozen (E) 2494 and then Ekind (E) = E_Incomplete_Type 2495 then 2496 declare 2497 Bod : constant Node_Id := Next (After); 2498 2499 begin 2500 -- The presence of a body freezes all entities previously 2501 -- declared in the current list of declarations, but this 2502 -- does not apply if the body does not come from source. 2503 -- A type invariant is transformed into a subprogram body 2504 -- which is placed at the end of the private part of the 2505 -- current package, but this body does not freeze incomplete 2506 -- types that may be declared in this private part. 2507 2508 if Comes_From_Source (Bod) 2509 and then Nkind (Bod) in N_Entry_Body 2510 | N_Package_Body 2511 | N_Protected_Body 2512 | N_Subprogram_Body 2513 | N_Task_Body 2514 | N_Body_Stub 2515 and then 2516 In_Same_List (After, Parent (E)) 2517 then 2518 Error_Msg_Sloc := Sloc (Next (After)); 2519 Error_Msg_NE 2520 ("type& is frozen# before its full declaration", 2521 Parent (E), E); 2522 end if; 2523 end; 2524 end if; 2525 2526 Next_Entity (E); 2527 end loop; 2528 end Freeze_All_Ent; 2529 2530 -- Local variables 2531 2532 Decl : Node_Id; 2533 E : Entity_Id; 2534 Item : Entity_Id; 2535 2536 -- Start of processing for Freeze_All 2537 2538 begin 2539 Freeze_All_Ent (From, After); 2540 2541 -- Now that all types are frozen, we can deal with default expressions 2542 -- that require us to build a default expression functions. This is the 2543 -- point at which such functions are constructed (after all types that 2544 -- might be used in such expressions have been frozen). 2545 2546 -- For subprograms that are renaming_as_body, we create the wrapper 2547 -- bodies as needed. 2548 2549 -- We also add finalization chains to access types whose designated 2550 -- types are controlled. This is normally done when freezing the type, 2551 -- but this misses recursive type definitions where the later members 2552 -- of the recursion introduce controlled components. 2553 2554 -- Loop through entities 2555 2556 E := From; 2557 while Present (E) loop 2558 if Is_Subprogram (E) then 2559 if not Default_Expressions_Processed (E) then 2560 Process_Default_Expressions (E, After); 2561 end if; 2562 2563 -- Check subprogram renamings for the same strub-mode. 2564 -- Avoid rechecking dispatching operations, that's taken 2565 -- care of in Check_Inherited_Conditions, that covers 2566 -- inherited interface operations. 2567 2568 Item := Alias (E); 2569 if Present (Item) 2570 and then not Is_Dispatching_Operation (E) 2571 then 2572 Check_Same_Strub_Mode (E, Item); 2573 end if; 2574 2575 if not Has_Completion (E) then 2576 Decl := Unit_Declaration_Node (E); 2577 2578 if Nkind (Decl) = N_Subprogram_Renaming_Declaration then 2579 if Error_Posted (Decl) then 2580 Set_Has_Completion (E); 2581 else 2582 Build_And_Analyze_Renamed_Body (Decl, E, After); 2583 end if; 2584 2585 elsif Nkind (Decl) = N_Subprogram_Declaration 2586 and then Present (Corresponding_Body (Decl)) 2587 and then 2588 Nkind (Unit_Declaration_Node (Corresponding_Body (Decl))) = 2589 N_Subprogram_Renaming_Declaration 2590 then 2591 Build_And_Analyze_Renamed_Body 2592 (Decl, Corresponding_Body (Decl), After); 2593 end if; 2594 end if; 2595 2596 -- Freeze the default expressions of entries, entry families, and 2597 -- protected subprograms. 2598 2599 elsif Is_Concurrent_Type (E) then 2600 Item := First_Entity (E); 2601 while Present (Item) loop 2602 if Is_Subprogram_Or_Entry (Item) 2603 and then not Default_Expressions_Processed (Item) 2604 then 2605 Process_Default_Expressions (Item, After); 2606 end if; 2607 2608 Next_Entity (Item); 2609 end loop; 2610 end if; 2611 2612 -- Historical note: We used to create a finalization master for an 2613 -- access type whose designated type is not controlled, but contains 2614 -- private controlled compoments. This form of postprocessing is no 2615 -- longer needed because the finalization master is now created when 2616 -- the access type is frozen (see Exp_Ch3.Freeze_Type). 2617 2618 Next_Entity (E); 2619 end loop; 2620 end Freeze_All; 2621 2622 ----------------------- 2623 -- Freeze_And_Append -- 2624 ----------------------- 2625 2626 procedure Freeze_And_Append 2627 (Ent : Entity_Id; 2628 N : Node_Id; 2629 Result : in out List_Id) 2630 is 2631 L : constant List_Id := Freeze_Entity (Ent, N); 2632 begin 2633 if Is_Non_Empty_List (L) then 2634 if Result = No_List then 2635 Result := L; 2636 else 2637 Append_List (L, Result); 2638 end if; 2639 end if; 2640 end Freeze_And_Append; 2641 2642 ------------------- 2643 -- Freeze_Before -- 2644 ------------------- 2645 2646 procedure Freeze_Before 2647 (N : Node_Id; 2648 T : Entity_Id; 2649 Do_Freeze_Profile : Boolean := True) 2650 is 2651 -- Freeze T, then insert the generated Freeze nodes before the node N. 2652 -- Flag Freeze_Profile is used when T is an overloadable entity, and 2653 -- indicates whether its profile should be frozen at the same time. 2654 2655 Freeze_Nodes : constant List_Id := 2656 Freeze_Entity (T, N, Do_Freeze_Profile); 2657 Pack : constant Entity_Id := Scope (T); 2658 2659 begin 2660 if Ekind (T) = E_Function then 2661 Check_Expression_Function (N, T); 2662 end if; 2663 2664 if Is_Non_Empty_List (Freeze_Nodes) then 2665 2666 -- If the entity is a type declared in an inner package, it may be 2667 -- frozen by an outer declaration before the package itself is 2668 -- frozen. Install the package scope to analyze the freeze nodes, 2669 -- which may include generated subprograms such as predicate 2670 -- functions, etc. 2671 2672 if Is_Type (T) and then From_Nested_Package (T) then 2673 Push_Scope (Pack); 2674 Install_Visible_Declarations (Pack); 2675 Install_Private_Declarations (Pack); 2676 Insert_Actions (N, Freeze_Nodes); 2677 End_Package_Scope (Pack); 2678 2679 else 2680 Insert_Actions (N, Freeze_Nodes); 2681 end if; 2682 end if; 2683 end Freeze_Before; 2684 2685 ------------------- 2686 -- Freeze_Entity -- 2687 ------------------- 2688 2689 -- WARNING: This routine manages Ghost regions. Return statements must be 2690 -- replaced by gotos which jump to the end of the routine and restore the 2691 -- Ghost mode. 2692 2693 function Freeze_Entity 2694 (E : Entity_Id; 2695 N : Node_Id; 2696 Do_Freeze_Profile : Boolean := True) return List_Id 2697 is 2698 Loc : constant Source_Ptr := Sloc (N); 2699 2700 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode; 2701 Saved_IGR : constant Node_Id := Ignored_Ghost_Region; 2702 -- Save the Ghost-related attributes to restore on exit 2703 2704 Atype : Entity_Id; 2705 Comp : Entity_Id; 2706 F_Node : Node_Id; 2707 Formal : Entity_Id; 2708 Indx : Node_Id; 2709 2710 Result : List_Id := No_List; 2711 -- List of freezing actions, left at No_List if none 2712 2713 Test_E : Entity_Id := E; 2714 -- This could use a comment ??? 2715 2716 procedure Add_To_Result (Fnod : Node_Id); 2717 -- Add freeze action Fnod to list Result 2718 2719 function After_Last_Declaration return Boolean; 2720 -- If Loc is a freeze_entity that appears after the last declaration 2721 -- in the scope, inhibit error messages on late completion. 2722 2723 procedure Check_Current_Instance (Comp_Decl : Node_Id); 2724 -- Check that an Access or Unchecked_Access attribute with a prefix 2725 -- which is the current instance type can only be applied when the type 2726 -- is limited. 2727 2728 procedure Check_No_Parts_Violations 2729 (Typ : Entity_Id; Aspect_No_Parts : Aspect_Id) with 2730 Pre => Aspect_No_Parts in 2731 Aspect_No_Controlled_Parts | Aspect_No_Task_Parts; 2732 -- Check that Typ does not violate the semantics of the specified 2733 -- Aspect_No_Parts (No_Controlled_Parts or No_Task_Parts) when it is 2734 -- specified on Typ or one of its ancestors. 2735 2736 procedure Check_Suspicious_Convention (Rec_Type : Entity_Id); 2737 -- Give a warning for pragma Convention with language C or C++ applied 2738 -- to a discriminated record type. This is suppressed for the unchecked 2739 -- union case, since the whole point in this case is interface C. We 2740 -- also do not generate this within instantiations, since we will have 2741 -- generated a message on the template. 2742 2743 procedure Check_Suspicious_Modulus (Utype : Entity_Id); 2744 -- Give warning for modulus of 8, 16, 32, 64 or 128 given as an explicit 2745 -- integer literal without an explicit corresponding size clause. The 2746 -- caller has checked that Utype is a modular integer type. 2747 2748 procedure Freeze_Array_Type (Arr : Entity_Id); 2749 -- Freeze array type, including freezing index and component types 2750 2751 procedure Freeze_Object_Declaration (E : Entity_Id); 2752 -- Perform checks and generate freeze node if needed for a constant or 2753 -- variable declared by an object declaration. 2754 2755 function Freeze_Generic_Entities (Pack : Entity_Id) return List_Id; 2756 -- Create Freeze_Generic_Entity nodes for types declared in a generic 2757 -- package. Recurse on inner generic packages. 2758 2759 function Freeze_Profile (E : Entity_Id) return Boolean; 2760 -- Freeze formals and return type of subprogram. If some type in the 2761 -- profile is incomplete and we are in an instance, freezing of the 2762 -- entity will take place elsewhere, and the function returns False. 2763 2764 procedure Freeze_Record_Type (Rec : Entity_Id); 2765 -- Freeze record type, including freezing component types, and freezing 2766 -- primitive operations if this is a tagged type. 2767 2768 function Has_Boolean_Aspect_Import (E : Entity_Id) return Boolean; 2769 -- Determine whether an arbitrary entity is subject to Boolean aspect 2770 -- Import and its value is specified as True. 2771 2772 procedure Inherit_Freeze_Node 2773 (Fnod : Node_Id; 2774 Typ : Entity_Id); 2775 -- Set type Typ's freeze node to refer to Fnode. This routine ensures 2776 -- that any attributes attached to Typ's original node are preserved. 2777 2778 procedure Wrap_Imported_Subprogram (E : Entity_Id); 2779 -- If E is an entity for an imported subprogram with pre/post-conditions 2780 -- then this procedure will create a wrapper to ensure that proper run- 2781 -- time checking of the pre/postconditions. See body for details. 2782 2783 ------------------- 2784 -- Add_To_Result -- 2785 ------------------- 2786 2787 procedure Add_To_Result (Fnod : Node_Id) is 2788 begin 2789 Append_New_To (Result, Fnod); 2790 end Add_To_Result; 2791 2792 ---------------------------- 2793 -- After_Last_Declaration -- 2794 ---------------------------- 2795 2796 function After_Last_Declaration return Boolean is 2797 Spec : constant Node_Id := Parent (Current_Scope); 2798 2799 begin 2800 if Nkind (Spec) = N_Package_Specification then 2801 if Present (Private_Declarations (Spec)) then 2802 return Loc >= Sloc (Last (Private_Declarations (Spec))); 2803 elsif Present (Visible_Declarations (Spec)) then 2804 return Loc >= Sloc (Last (Visible_Declarations (Spec))); 2805 else 2806 return False; 2807 end if; 2808 2809 else 2810 return False; 2811 end if; 2812 end After_Last_Declaration; 2813 2814 ---------------------------- 2815 -- Check_Current_Instance -- 2816 ---------------------------- 2817 2818 procedure Check_Current_Instance (Comp_Decl : Node_Id) is 2819 2820 function Is_Aliased_View_Of_Type (Typ : Entity_Id) return Boolean; 2821 -- Determine whether Typ is compatible with the rules for aliased 2822 -- views of types as defined in RM 3.10 in the various dialects. 2823 2824 function Process (N : Node_Id) return Traverse_Result; 2825 -- Process routine to apply check to given node 2826 2827 ----------------------------- 2828 -- Is_Aliased_View_Of_Type -- 2829 ----------------------------- 2830 2831 function Is_Aliased_View_Of_Type (Typ : Entity_Id) return Boolean is 2832 Typ_Decl : constant Node_Id := Parent (Typ); 2833 2834 begin 2835 -- Common case 2836 2837 if Nkind (Typ_Decl) = N_Full_Type_Declaration 2838 and then Limited_Present (Type_Definition (Typ_Decl)) 2839 then 2840 return True; 2841 2842 -- The following paragraphs describe what a legal aliased view of 2843 -- a type is in the various dialects of Ada. 2844 2845 -- Ada 95 2846 2847 -- The current instance of a limited type, and a formal parameter 2848 -- or generic formal object of a tagged type. 2849 2850 -- Ada 95 limited type 2851 -- * Type with reserved word "limited" 2852 -- * A protected or task type 2853 -- * A composite type with limited component 2854 2855 elsif Ada_Version <= Ada_95 then 2856 return Is_Limited_Type (Typ); 2857 2858 -- Ada 2005 2859 2860 -- The current instance of a limited tagged type, a protected 2861 -- type, a task type, or a type that has the reserved word 2862 -- "limited" in its full definition ... a formal parameter or 2863 -- generic formal object of a tagged type. 2864 2865 -- Ada 2005 limited type 2866 -- * Type with reserved word "limited", "synchronized", "task" 2867 -- or "protected" 2868 -- * A composite type with limited component 2869 -- * A derived type whose parent is a non-interface limited type 2870 2871 elsif Ada_Version = Ada_2005 then 2872 return 2873 (Is_Limited_Type (Typ) and then Is_Tagged_Type (Typ)) 2874 or else 2875 (Is_Derived_Type (Typ) 2876 and then not Is_Interface (Etype (Typ)) 2877 and then Is_Limited_Type (Etype (Typ))); 2878 2879 -- Ada 2012 and beyond 2880 2881 -- The current instance of an immutably limited type ... a formal 2882 -- parameter or generic formal object of a tagged type. 2883 2884 -- Ada 2012 limited type 2885 -- * Type with reserved word "limited", "synchronized", "task" 2886 -- or "protected" 2887 -- * A composite type with limited component 2888 -- * A derived type whose parent is a non-interface limited type 2889 -- * An incomplete view 2890 2891 -- Ada 2012 immutably limited type 2892 -- * Explicitly limited record type 2893 -- * Record extension with "limited" present 2894 -- * Non-formal limited private type that is either tagged 2895 -- or has at least one access discriminant with a default 2896 -- expression 2897 -- * Task type, protected type or synchronized interface 2898 -- * Type derived from immutably limited type 2899 2900 else 2901 return 2902 Is_Immutably_Limited_Type (Typ) 2903 or else Is_Incomplete_Type (Typ); 2904 end if; 2905 end Is_Aliased_View_Of_Type; 2906 2907 ------------- 2908 -- Process -- 2909 ------------- 2910 2911 function Process (N : Node_Id) return Traverse_Result is 2912 begin 2913 case Nkind (N) is 2914 when N_Attribute_Reference => 2915 if Attribute_Name (N) in Name_Access | Name_Unchecked_Access 2916 and then Is_Entity_Name (Prefix (N)) 2917 and then Is_Type (Entity (Prefix (N))) 2918 and then Entity (Prefix (N)) = E 2919 then 2920 if Ada_Version < Ada_2012 then 2921 Error_Msg_N 2922 ("current instance must be a limited type", 2923 Prefix (N)); 2924 else 2925 Error_Msg_N 2926 ("current instance must be an immutably limited " 2927 & "type (RM-2012, 7.5 (8.1/3))", Prefix (N)); 2928 end if; 2929 2930 return Abandon; 2931 2932 else 2933 return OK; 2934 end if; 2935 2936 when others => 2937 return OK; 2938 end case; 2939 end Process; 2940 2941 procedure Traverse is new Traverse_Proc (Process); 2942 2943 -- Local variables 2944 2945 Rec_Type : constant Entity_Id := 2946 Scope (Defining_Identifier (Comp_Decl)); 2947 2948 -- Start of processing for Check_Current_Instance 2949 2950 begin 2951 if not Is_Aliased_View_Of_Type (Rec_Type) then 2952 Traverse (Comp_Decl); 2953 end if; 2954 end Check_Current_Instance; 2955 2956 ------------------------------- 2957 -- Check_No_Parts_Violations -- 2958 ------------------------------- 2959 2960 procedure Check_No_Parts_Violations 2961 (Typ : Entity_Id; Aspect_No_Parts : Aspect_Id) 2962 is 2963 2964 function Find_Aspect_No_Parts 2965 (Typ : Entity_Id) return Node_Id; 2966 -- Search for Aspect_No_Parts on a given type. When 2967 -- the aspect is not explicity specified Empty is returned. 2968 2969 function Get_Aspect_No_Parts_Value 2970 (Typ : Entity_Id) return Entity_Id; 2971 -- Obtain the value for the Aspect_No_Parts on a given 2972 -- type. When the aspect is not explicitly specified Empty is 2973 -- returned. 2974 2975 function Has_Aspect_No_Parts 2976 (Typ : Entity_Id) return Boolean; 2977 -- Predicate function which identifies whether No_Parts 2978 -- is explicitly specified on a given type. 2979 2980 ------------------------------------- 2981 -- Find_Aspect_No_Parts -- 2982 ------------------------------------- 2983 2984 function Find_Aspect_No_Parts 2985 (Typ : Entity_Id) return Node_Id 2986 is 2987 Partial_View : constant Entity_Id := 2988 Incomplete_Or_Partial_View (Typ); 2989 2990 Aspect_Spec : Entity_Id := 2991 Find_Aspect (Typ, Aspect_No_Parts); 2992 Curr_Aspect_Spec : Entity_Id; 2993 begin 2994 2995 -- Examine Typ's associated node, when present, since aspect 2996 -- specifications do not get transferred when nodes get rewritten. 2997 2998 -- For example, this can happen in the expansion of array types 2999 3000 if No (Aspect_Spec) 3001 and then Present (Associated_Node_For_Itype (Typ)) 3002 and then Nkind (Associated_Node_For_Itype (Typ)) 3003 = N_Full_Type_Declaration 3004 then 3005 Aspect_Spec := 3006 Find_Aspect 3007 (Id => Defining_Identifier 3008 (Associated_Node_For_Itype (Typ)), 3009 A => Aspect_No_Parts); 3010 end if; 3011 3012 -- Examine aspects specifications on private type declarations 3013 3014 -- Should Find_Aspect be improved to handle this case ??? 3015 3016 if No (Aspect_Spec) 3017 and then Present (Partial_View) 3018 and then Present 3019 (Aspect_Specifications 3020 (Declaration_Node 3021 (Partial_View))) 3022 then 3023 Curr_Aspect_Spec := 3024 First 3025 (Aspect_Specifications 3026 (Declaration_Node 3027 (Partial_View))); 3028 3029 -- Search through aspects present on the private type 3030 3031 while Present (Curr_Aspect_Spec) loop 3032 if Get_Aspect_Id (Curr_Aspect_Spec) 3033 = Aspect_No_Parts 3034 then 3035 Aspect_Spec := Curr_Aspect_Spec; 3036 exit; 3037 end if; 3038 3039 Next (Curr_Aspect_Spec); 3040 end loop; 3041 3042 end if; 3043 3044 -- When errors are posted on the aspect return Empty 3045 3046 if Error_Posted (Aspect_Spec) then 3047 return Empty; 3048 end if; 3049 3050 return Aspect_Spec; 3051 end Find_Aspect_No_Parts; 3052 3053 ------------------------------------------ 3054 -- Get_Aspect_No_Parts_Value -- 3055 ------------------------------------------ 3056 3057 function Get_Aspect_No_Parts_Value 3058 (Typ : Entity_Id) return Entity_Id 3059 is 3060 Aspect_Spec : constant Entity_Id := 3061 Find_Aspect_No_Parts (Typ); 3062 begin 3063 3064 -- Return the value of the aspect when present 3065 3066 if Present (Aspect_Spec) then 3067 3068 -- No expression is the same as True 3069 3070 if No (Expression (Aspect_Spec)) then 3071 return Standard_True; 3072 end if; 3073 3074 -- Assume its expression has already been constant folded into 3075 -- a Boolean value and return its value. 3076 3077 return Entity (Expression (Aspect_Spec)); 3078 end if; 3079 3080 -- Otherwise, the aspect is not specified - so return Empty 3081 3082 return Empty; 3083 end Get_Aspect_No_Parts_Value; 3084 3085 ------------------------------------ 3086 -- Has_Aspect_No_Parts -- 3087 ------------------------------------ 3088 3089 function Has_Aspect_No_Parts 3090 (Typ : Entity_Id) return Boolean 3091 is (Present (Find_Aspect_No_Parts (Typ))); 3092 3093 -- Generic instances 3094 3095 ------------------------------------------- 3096 -- Get_Generic_Formal_Types_In_Hierarchy -- 3097 ------------------------------------------- 3098 3099 function Get_Generic_Formal_Types_In_Hierarchy 3100 is new Collect_Types_In_Hierarchy (Predicate => Is_Generic_Formal); 3101 -- Return a list of all types within a given type's hierarchy which 3102 -- are generic formals. 3103 3104 ---------------------------------------- 3105 -- Get_Types_With_Aspect_In_Hierarchy -- 3106 ---------------------------------------- 3107 3108 function Get_Types_With_Aspect_In_Hierarchy 3109 is new Collect_Types_In_Hierarchy 3110 (Predicate => Has_Aspect_No_Parts); 3111 -- Returns a list of all types within a given type's hierarchy which 3112 -- have the Aspect_No_Parts specified. 3113 3114 -- Local declarations 3115 3116 Aspect_Value : Entity_Id; 3117 Curr_Value : Entity_Id; 3118 Curr_Typ_Elmt : Elmt_Id; 3119 Curr_Body_Elmt : Elmt_Id; 3120 Curr_Formal_Elmt : Elmt_Id; 3121 Gen_Bodies : Elist_Id; 3122 Gen_Formals : Elist_Id; 3123 Scop : Entity_Id; 3124 Types_With_Aspect : Elist_Id; 3125 3126 -- Start of processing for Check_No_Parts_Violations 3127 3128 begin 3129 -- Nothing to check if the type is elementary or artificial 3130 3131 if Is_Elementary_Type (Typ) or else not Comes_From_Source (Typ) then 3132 return; 3133 end if; 3134 3135 Types_With_Aspect := Get_Types_With_Aspect_In_Hierarchy (Typ); 3136 3137 -- Nothing to check if there are no types with No_Parts specified 3138 3139 if Is_Empty_Elmt_List (Types_With_Aspect) then 3140 return; 3141 end if; 3142 3143 -- Set name for all errors below 3144 3145 Error_Msg_Name_1 := Aspect_Names (Aspect_No_Parts); 3146 3147 -- Obtain the aspect value for No_Parts for comparison 3148 3149 Aspect_Value := 3150 Get_Aspect_No_Parts_Value 3151 (Node (First_Elmt (Types_With_Aspect))); 3152 3153 -- When the value is True and there are controlled/task parts or the 3154 -- type itself is controlled/task, trigger the appropriate error. 3155 3156 if Aspect_Value = Standard_True then 3157 if Aspect_No_Parts = Aspect_No_Controlled_Parts then 3158 if Is_Controlled (Typ) or else Has_Controlled_Component (Typ) 3159 then 3160 Error_Msg_N 3161 ("aspect % applied to controlled type &", Typ); 3162 end if; 3163 3164 elsif Aspect_No_Parts = Aspect_No_Task_Parts then 3165 if Has_Task (Typ) then 3166 Error_Msg_N 3167 ("aspect % applied to task type &", Typ); 3168 end if; 3169 3170 else 3171 raise Program_Error; 3172 end if; 3173 end if; 3174 3175 -- Move through Types_With_Aspect - checking that the value specified 3176 -- for their corresponding Aspect_No_Parts do not override each 3177 -- other. 3178 3179 Curr_Typ_Elmt := First_Elmt (Types_With_Aspect); 3180 while Present (Curr_Typ_Elmt) loop 3181 Curr_Value := 3182 Get_Aspect_No_Parts_Value (Node (Curr_Typ_Elmt)); 3183 3184 -- Compare the aspect value against the current type 3185 3186 if Curr_Value /= Aspect_Value then 3187 Error_Msg_NE 3188 ("cannot override aspect % of " 3189 & "ancestor type &", Typ, Node (Curr_Typ_Elmt)); 3190 return; 3191 end if; 3192 3193 Next_Elmt (Curr_Typ_Elmt); 3194 end loop; 3195 3196 -- Issue an error if the aspect applies to a type declared inside a 3197 -- generic body and if said type derives from or has a component 3198 -- of ageneric formal type - since those are considered to have 3199 -- controlled/task parts and have Aspect_No_Parts specified as 3200 -- False by default (RM H.4.1(4/5) is about the language-defined 3201 -- No_Controlled_Parts aspect, and we are using the same rules for 3202 -- No_Task_Parts). 3203 3204 -- We do not check tagged types since deriving from a formal type 3205 -- within an enclosing generic unit is already illegal 3206 -- (RM 3.9.1 (4/2)). 3207 3208 if Aspect_Value = Standard_True 3209 and then In_Generic_Body (Typ) 3210 and then not Is_Tagged_Type (Typ) 3211 then 3212 Gen_Bodies := New_Elmt_List; 3213 Gen_Formals := 3214 Get_Generic_Formal_Types_In_Hierarchy 3215 (Typ => Typ, 3216 Examine_Components => True); 3217 3218 -- Climb scopes collecting generic bodies 3219 3220 Scop := Scope (Typ); 3221 while Present (Scop) and then Scop /= Standard_Standard loop 3222 3223 -- Generic package body 3224 3225 if Ekind (Scop) = E_Generic_Package 3226 and then In_Package_Body (Scop) 3227 then 3228 Append_Elmt (Scop, Gen_Bodies); 3229 3230 -- Generic subprogram body 3231 3232 elsif Is_Generic_Subprogram (Scop) then 3233 Append_Elmt (Scop, Gen_Bodies); 3234 end if; 3235 3236 Scop := Scope (Scop); 3237 end loop; 3238 3239 -- Warn about the improper use of Aspect_No_Parts on a type 3240 -- declaration deriving from or that has a component of a generic 3241 -- formal type within the formal type's corresponding generic 3242 -- body by moving through all formal types in Typ's hierarchy and 3243 -- checking if they are formals in any of the enclosing generic 3244 -- bodies. 3245 3246 -- However, a special exception gets made for formal types which 3247 -- derive from a type which has Aspect_No_Parts True. 3248 3249 -- For example: 3250 3251 -- generic 3252 -- type Form is private; 3253 -- package G is 3254 -- type Type_A is new Form with No_Controlled_Parts; -- OK 3255 -- end; 3256 -- 3257 -- package body G is 3258 -- type Type_B is new Form with No_Controlled_Parts; -- ERROR 3259 -- end; 3260 3261 -- generic 3262 -- type Form is private; 3263 -- package G is 3264 -- type Type_A is record C : Form; end record 3265 -- with No_Controlled_Parts; -- OK 3266 -- end; 3267 -- 3268 -- package body G is 3269 -- type Type_B is record C : Form; end record 3270 -- with No_Controlled_Parts; -- ERROR 3271 -- end; 3272 3273 -- type Root is tagged null record with No_Controlled_Parts; 3274 -- 3275 -- generic 3276 -- type Form is new Root with private; 3277 -- package G is 3278 -- type Type_A is record C : Form; end record 3279 -- with No_Controlled_Parts; -- OK 3280 -- end; 3281 -- 3282 -- package body G is 3283 -- type Type_B is record C : Form; end record 3284 -- with No_Controlled_Parts; -- OK 3285 -- end; 3286 3287 Curr_Formal_Elmt := First_Elmt (Gen_Formals); 3288 while Present (Curr_Formal_Elmt) loop 3289 3290 Curr_Body_Elmt := First_Elmt (Gen_Bodies); 3291 while Present (Curr_Body_Elmt) loop 3292 3293 -- Obtain types in the formal type's hierarchy which have 3294 -- the aspect specified. 3295 3296 Types_With_Aspect := 3297 Get_Types_With_Aspect_In_Hierarchy 3298 (Node (Curr_Formal_Elmt)); 3299 3300 -- We found a type declaration in a generic body where both 3301 -- Aspect_No_Parts is true and one of its ancestors is a 3302 -- generic formal type. 3303 3304 if Scope (Node (Curr_Formal_Elmt)) = 3305 Node (Curr_Body_Elmt) 3306 3307 -- Check that no ancestors of the formal type have 3308 -- Aspect_No_Parts True before issuing the error. 3309 3310 and then (Is_Empty_Elmt_List (Types_With_Aspect) 3311 or else 3312 Get_Aspect_No_Parts_Value 3313 (Node (First_Elmt (Types_With_Aspect))) 3314 = Standard_False) 3315 then 3316 Error_Msg_Node_1 := Typ; 3317 Error_Msg_Node_2 := Node (Curr_Formal_Elmt); 3318 Error_Msg 3319 ("aspect % cannot be applied to " 3320 & "type & which has an ancestor or component of " 3321 & "formal type & within the formal type's " 3322 & "corresponding generic body", Sloc (Typ)); 3323 end if; 3324 3325 Next_Elmt (Curr_Body_Elmt); 3326 end loop; 3327 3328 Next_Elmt (Curr_Formal_Elmt); 3329 end loop; 3330 end if; 3331 end Check_No_Parts_Violations; 3332 3333 --------------------------------- 3334 -- Check_Suspicious_Convention -- 3335 --------------------------------- 3336 3337 procedure Check_Suspicious_Convention (Rec_Type : Entity_Id) is 3338 begin 3339 if Has_Discriminants (Rec_Type) 3340 and then Is_Base_Type (Rec_Type) 3341 and then not Is_Unchecked_Union (Rec_Type) 3342 and then (Convention (Rec_Type) = Convention_C 3343 or else 3344 Convention (Rec_Type) = Convention_CPP) 3345 and then Comes_From_Source (Rec_Type) 3346 and then not In_Instance 3347 and then not Has_Warnings_Off (Rec_Type) 3348 then 3349 declare 3350 Cprag : constant Node_Id := 3351 Get_Rep_Pragma (Rec_Type, Name_Convention); 3352 A2 : Node_Id; 3353 3354 begin 3355 if Present (Cprag) then 3356 A2 := Next (First (Pragma_Argument_Associations (Cprag))); 3357 3358 if Convention (Rec_Type) = Convention_C then 3359 Error_Msg_N 3360 ("?x?discriminated record has no direct equivalent in " 3361 & "C", A2); 3362 else 3363 Error_Msg_N 3364 ("?x?discriminated record has no direct equivalent in " 3365 & "C++", A2); 3366 end if; 3367 3368 Error_Msg_NE 3369 ("\?x?use of convention for type& is dubious", 3370 A2, Rec_Type); 3371 end if; 3372 end; 3373 end if; 3374 end Check_Suspicious_Convention; 3375 3376 ------------------------------ 3377 -- Check_Suspicious_Modulus -- 3378 ------------------------------ 3379 3380 procedure Check_Suspicious_Modulus (Utype : Entity_Id) is 3381 Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype)); 3382 3383 begin 3384 if not Warn_On_Suspicious_Modulus_Value then 3385 return; 3386 end if; 3387 3388 if Nkind (Decl) = N_Full_Type_Declaration then 3389 declare 3390 Tdef : constant Node_Id := Type_Definition (Decl); 3391 3392 begin 3393 if Nkind (Tdef) = N_Modular_Type_Definition then 3394 declare 3395 Modulus : constant Node_Id := 3396 Original_Node (Expression (Tdef)); 3397 3398 begin 3399 if Nkind (Modulus) = N_Integer_Literal then 3400 declare 3401 Modv : constant Uint := Intval (Modulus); 3402 Sizv : constant Uint := RM_Size (Utype); 3403 3404 begin 3405 -- First case, modulus and size are the same. This 3406 -- happens if you have something like mod 32, with 3407 -- an explicit size of 32, this is for sure a case 3408 -- where the warning is given, since it is seems 3409 -- very unlikely that someone would want e.g. a 3410 -- five bit type stored in 32 bits. It is much 3411 -- more likely they wanted a 32-bit type. 3412 3413 if Modv = Sizv then 3414 null; 3415 3416 -- Second case, the modulus is 32 or 64 and no 3417 -- size clause is present. This is a less clear 3418 -- case for giving the warning, but in the case 3419 -- of 32/64 (5-bit or 6-bit types) these seem rare 3420 -- enough that it is a likely error (and in any 3421 -- case using 2**5 or 2**6 in these cases seems 3422 -- clearer. We don't include 8 or 16 here, simply 3423 -- because in practice 3-bit and 4-bit types are 3424 -- more common and too many false positives if 3425 -- we warn in these cases. 3426 3427 elsif not Has_Size_Clause (Utype) 3428 and then (Modv = Uint_32 or else Modv = Uint_64) 3429 then 3430 null; 3431 3432 -- No warning needed 3433 3434 else 3435 return; 3436 end if; 3437 3438 -- If we fall through, give warning 3439 3440 Error_Msg_Uint_1 := Modv; 3441 Error_Msg_N 3442 ("?.m?2 '*'*^' may have been intended here", 3443 Modulus); 3444 end; 3445 end if; 3446 end; 3447 end if; 3448 end; 3449 end if; 3450 end Check_Suspicious_Modulus; 3451 3452 ----------------------- 3453 -- Freeze_Array_Type -- 3454 ----------------------- 3455 3456 procedure Freeze_Array_Type (Arr : Entity_Id) is 3457 FS : constant Entity_Id := First_Subtype (Arr); 3458 Ctyp : constant Entity_Id := Component_Type (Arr); 3459 Clause : Entity_Id; 3460 3461 Non_Standard_Enum : Boolean := False; 3462 -- Set true if any of the index types is an enumeration type with a 3463 -- non-standard representation. 3464 3465 begin 3466 Freeze_And_Append (Ctyp, N, Result); 3467 3468 Indx := First_Index (Arr); 3469 while Present (Indx) loop 3470 Freeze_And_Append (Etype (Indx), N, Result); 3471 3472 if Is_Enumeration_Type (Etype (Indx)) 3473 and then Has_Non_Standard_Rep (Etype (Indx)) 3474 then 3475 Non_Standard_Enum := True; 3476 end if; 3477 3478 Next_Index (Indx); 3479 end loop; 3480 3481 -- Processing that is done only for base types 3482 3483 if Ekind (Arr) = E_Array_Type then 3484 3485 -- Deal with default setting of reverse storage order 3486 3487 Set_SSO_From_Default (Arr); 3488 3489 -- Propagate flags for component type 3490 3491 if Is_Controlled (Ctyp) 3492 or else Has_Controlled_Component (Ctyp) 3493 then 3494 Set_Has_Controlled_Component (Arr); 3495 end if; 3496 3497 if Has_Unchecked_Union (Ctyp) then 3498 Set_Has_Unchecked_Union (Arr); 3499 end if; 3500 3501 -- The array type requires its own invariant procedure in order to 3502 -- verify the component invariant over all elements. In GNATprove 3503 -- mode, the component invariants are checked by other means. They 3504 -- should not be added to the array type invariant procedure, so 3505 -- that the procedure can be used to check the array type 3506 -- invariants if any. 3507 3508 if Has_Invariants (Ctyp) 3509 and then not GNATprove_Mode 3510 then 3511 Set_Has_Own_Invariants (Arr); 3512 end if; 3513 3514 -- Warn for pragma Pack overriding foreign convention 3515 3516 if Has_Foreign_Convention (Ctyp) 3517 and then Has_Pragma_Pack (Arr) 3518 then 3519 declare 3520 CN : constant Name_Id := 3521 Get_Convention_Name (Convention (Ctyp)); 3522 PP : constant Node_Id := 3523 Get_Pragma (First_Subtype (Arr), Pragma_Pack); 3524 begin 3525 if Present (PP) then 3526 Error_Msg_Name_1 := CN; 3527 Error_Msg_Sloc := Sloc (Arr); 3528 Error_Msg_N 3529 ("pragma Pack affects convention % components #??", PP); 3530 Error_Msg_Name_1 := CN; 3531 Error_Msg_N 3532 ("\array components may not have % compatible " 3533 & "representation??", PP); 3534 end if; 3535 end; 3536 end if; 3537 3538 -- Check for Aliased or Atomic_Components or Full Access with 3539 -- unsuitable packing or explicit component size clause given. 3540 3541 if (Has_Aliased_Components (Arr) 3542 or else Has_Atomic_Components (Arr) 3543 or else Is_Full_Access (Ctyp)) 3544 and then 3545 (Has_Component_Size_Clause (Arr) or else Is_Packed (Arr)) 3546 then 3547 Alias_Atomic_Check : declare 3548 3549 procedure Complain_CS (T : String); 3550 -- Outputs error messages for incorrect CS clause or pragma 3551 -- Pack for aliased or full access components (T is either 3552 -- "aliased" or "atomic" or "volatile full access"); 3553 3554 ----------------- 3555 -- Complain_CS -- 3556 ----------------- 3557 3558 procedure Complain_CS (T : String) is 3559 begin 3560 if Has_Component_Size_Clause (Arr) then 3561 Clause := 3562 Get_Attribute_Definition_Clause 3563 (FS, Attribute_Component_Size); 3564 3565 Error_Msg_N 3566 ("incorrect component size for " 3567 & T & " components", Clause); 3568 Error_Msg_Uint_1 := Esize (Ctyp); 3569 Error_Msg_N 3570 ("\only allowed value is^", Clause); 3571 3572 else 3573 Error_Msg_N 3574 ("?cannot pack " & T & " components (RM 13.2(7))", 3575 Get_Rep_Pragma (FS, Name_Pack)); 3576 Set_Is_Packed (Arr, False); 3577 end if; 3578 end Complain_CS; 3579 3580 -- Start of processing for Alias_Atomic_Check 3581 3582 begin 3583 -- If object size of component type isn't known, we cannot 3584 -- be sure so we defer to the back end. 3585 3586 if not Known_Static_Esize (Ctyp) then 3587 null; 3588 3589 -- Case where component size has no effect. First check for 3590 -- object size of component type multiple of the storage 3591 -- unit size. 3592 3593 elsif Esize (Ctyp) mod System_Storage_Unit = 0 3594 3595 -- OK in both packing case and component size case if RM 3596 -- size is known and static and same as the object size. 3597 3598 and then 3599 ((Known_Static_RM_Size (Ctyp) 3600 and then Esize (Ctyp) = RM_Size (Ctyp)) 3601 3602 -- Or if we have an explicit component size clause and 3603 -- the component size and object size are equal. 3604 3605 or else 3606 (Has_Component_Size_Clause (Arr) 3607 and then Component_Size (Arr) = Esize (Ctyp))) 3608 then 3609 null; 3610 3611 elsif Has_Aliased_Components (Arr) then 3612 Complain_CS ("aliased"); 3613 3614 elsif Has_Atomic_Components (Arr) 3615 or else Is_Atomic (Ctyp) 3616 then 3617 Complain_CS ("atomic"); 3618 3619 elsif Is_Volatile_Full_Access (Ctyp) then 3620 Complain_CS ("volatile full access"); 3621 end if; 3622 end Alias_Atomic_Check; 3623 end if; 3624 3625 -- Check for Independent_Components/Independent with unsuitable 3626 -- packing or explicit component size clause given. 3627 3628 if (Has_Independent_Components (Arr) or else Is_Independent (Ctyp)) 3629 and then 3630 (Has_Component_Size_Clause (Arr) or else Is_Packed (Arr)) 3631 then 3632 begin 3633 -- If object size of component type isn't known, we cannot 3634 -- be sure so we defer to the back end. 3635 3636 if not Known_Static_Esize (Ctyp) then 3637 null; 3638 3639 -- Case where component size has no effect. First check for 3640 -- object size of component type multiple of the storage 3641 -- unit size. 3642 3643 elsif Esize (Ctyp) mod System_Storage_Unit = 0 3644 3645 -- OK in both packing case and component size case if RM 3646 -- size is known and multiple of the storage unit size. 3647 3648 and then 3649 ((Known_Static_RM_Size (Ctyp) 3650 and then RM_Size (Ctyp) mod System_Storage_Unit = 0) 3651 3652 -- Or if we have an explicit component size clause and 3653 -- the component size is larger than the object size. 3654 3655 or else 3656 (Has_Component_Size_Clause (Arr) 3657 and then Component_Size (Arr) >= Esize (Ctyp))) 3658 then 3659 null; 3660 3661 else 3662 if Has_Component_Size_Clause (Arr) then 3663 Clause := 3664 Get_Attribute_Definition_Clause 3665 (FS, Attribute_Component_Size); 3666 3667 Error_Msg_N 3668 ("incorrect component size for " 3669 & "independent components", Clause); 3670 Error_Msg_Uint_1 := Esize (Ctyp); 3671 Error_Msg_N 3672 ("\minimum allowed is^", Clause); 3673 3674 else 3675 Error_Msg_N 3676 ("?cannot pack independent components (RM 13.2(7))", 3677 Get_Rep_Pragma (FS, Name_Pack)); 3678 Set_Is_Packed (Arr, False); 3679 end if; 3680 end if; 3681 end; 3682 end if; 3683 3684 -- If packing was requested or if the component size was 3685 -- set explicitly, then see if bit packing is required. This 3686 -- processing is only done for base types, since all of the 3687 -- representation aspects involved are type-related. 3688 3689 -- This is not just an optimization, if we start processing the 3690 -- subtypes, they interfere with the settings on the base type 3691 -- (this is because Is_Packed has a slightly different meaning 3692 -- before and after freezing). 3693 3694 declare 3695 Csiz : Uint; 3696 Esiz : Uint; 3697 3698 begin 3699 if Is_Packed (Arr) 3700 and then Known_Static_RM_Size (Ctyp) 3701 and then not Has_Component_Size_Clause (Arr) 3702 then 3703 Csiz := UI_Max (RM_Size (Ctyp), 1); 3704 3705 elsif Known_Component_Size (Arr) then 3706 Csiz := Component_Size (Arr); 3707 3708 elsif not Known_Static_Esize (Ctyp) then 3709 Csiz := Uint_0; 3710 3711 else 3712 Esiz := Esize (Ctyp); 3713 3714 -- We can set the component size if it is less than 16, 3715 -- rounding it up to the next storage unit size. 3716 3717 if Esiz <= 8 then 3718 Csiz := Uint_8; 3719 elsif Esiz <= 16 then 3720 Csiz := Uint_16; 3721 else 3722 Csiz := Uint_0; 3723 end if; 3724 3725 -- Set component size up to match alignment if it would 3726 -- otherwise be less than the alignment. This deals with 3727 -- cases of types whose alignment exceeds their size (the 3728 -- padded type cases). 3729 3730 if Csiz /= 0 and then Known_Alignment (Ctyp) then 3731 declare 3732 A : constant Uint := Alignment_In_Bits (Ctyp); 3733 begin 3734 if Csiz < A then 3735 Csiz := A; 3736 end if; 3737 end; 3738 end if; 3739 end if; 3740 3741 -- Case of component size that may result in bit packing 3742 3743 if 1 <= Csiz and then Csiz <= System_Max_Integer_Size then 3744 declare 3745 Ent : constant Entity_Id := 3746 First_Subtype (Arr); 3747 Pack_Pragma : constant Node_Id := 3748 Get_Rep_Pragma (Ent, Name_Pack); 3749 Comp_Size_C : constant Node_Id := 3750 Get_Attribute_Definition_Clause 3751 (Ent, Attribute_Component_Size); 3752 3753 begin 3754 -- Warn if we have pack and component size so that the 3755 -- pack is ignored. 3756 3757 -- Note: here we must check for the presence of a 3758 -- component size before checking for a Pack pragma to 3759 -- deal with the case where the array type is a derived 3760 -- type whose parent is currently private. 3761 3762 if Present (Comp_Size_C) 3763 and then Has_Pragma_Pack (Ent) 3764 and then Warn_On_Redundant_Constructs 3765 then 3766 Error_Msg_Sloc := Sloc (Comp_Size_C); 3767 Error_Msg_NE 3768 ("?r?pragma Pack for& ignored!", Pack_Pragma, Ent); 3769 Error_Msg_N 3770 ("\?r?explicit component size given#!", Pack_Pragma); 3771 Set_Is_Packed (Base_Type (Ent), False); 3772 Set_Is_Bit_Packed_Array (Base_Type (Ent), False); 3773 end if; 3774 3775 -- Set component size if not already set by a component 3776 -- size clause. 3777 3778 if not Present (Comp_Size_C) then 3779 Set_Component_Size (Arr, Csiz); 3780 end if; 3781 3782 -- Check for base type of 8, 16, 32 bits, where an 3783 -- unsigned subtype has a length one less than the 3784 -- base type (e.g. Natural subtype of Integer). 3785 3786 -- In such cases, if a component size was not set 3787 -- explicitly, then generate a warning. 3788 3789 if Has_Pragma_Pack (Arr) 3790 and then not Present (Comp_Size_C) 3791 and then (Csiz = 7 or else Csiz = 15 or else Csiz = 31) 3792 and then Known_Esize (Base_Type (Ctyp)) 3793 and then Esize (Base_Type (Ctyp)) = Csiz + 1 3794 then 3795 Error_Msg_Uint_1 := Csiz; 3796 3797 if Present (Pack_Pragma) then 3798 Error_Msg_N 3799 ("??pragma Pack causes component size to be ^!", 3800 Pack_Pragma); 3801 Error_Msg_N 3802 ("\??use Component_Size to set desired value!", 3803 Pack_Pragma); 3804 end if; 3805 end if; 3806 3807 -- Bit packing is never needed for 8, 16, 32, 64 or 128 3808 3809 if Addressable (Csiz) then 3810 3811 -- If the Esize of the component is known and equal to 3812 -- the component size then even packing is not needed. 3813 3814 if Known_Static_Esize (Ctyp) 3815 and then Esize (Ctyp) = Csiz 3816 then 3817 -- Here the array was requested to be packed, but 3818 -- the packing request had no effect whatsoever, 3819 -- so flag Is_Packed is reset. 3820 3821 -- Note: semantically this means that we lose track 3822 -- of the fact that a derived type inherited pragma 3823 -- Pack that was non-effective, but that is fine. 3824 3825 -- We regard a Pack pragma as a request to set a 3826 -- representation characteristic, and this request 3827 -- may be ignored. 3828 3829 Set_Is_Packed (Base_Type (Arr), False); 3830 Set_Has_Non_Standard_Rep (Base_Type (Arr), False); 3831 else 3832 Set_Is_Packed (Base_Type (Arr), True); 3833 Set_Has_Non_Standard_Rep (Base_Type (Arr), True); 3834 end if; 3835 3836 Set_Is_Bit_Packed_Array (Base_Type (Arr), False); 3837 3838 -- Bit packing is not needed for multiples of the storage 3839 -- unit if the type is composite because the back end can 3840 -- byte pack composite types efficiently. That's not true 3841 -- for discrete types because every read would generate a 3842 -- lot of instructions, so we keep using the manipulation 3843 -- routines of the runtime for them. 3844 3845 elsif Csiz mod System_Storage_Unit = 0 3846 and then Is_Composite_Type (Ctyp) 3847 then 3848 Set_Is_Packed (Base_Type (Arr), True); 3849 Set_Has_Non_Standard_Rep (Base_Type (Arr), True); 3850 Set_Is_Bit_Packed_Array (Base_Type (Arr), False); 3851 3852 -- In all other cases, bit packing is needed 3853 3854 else 3855 Set_Is_Packed (Base_Type (Arr), True); 3856 Set_Has_Non_Standard_Rep (Base_Type (Arr), True); 3857 Set_Is_Bit_Packed_Array (Base_Type (Arr), True); 3858 end if; 3859 end; 3860 end if; 3861 end; 3862 3863 -- Warn for case of atomic type 3864 3865 Clause := Get_Rep_Pragma (FS, Name_Atomic); 3866 3867 if Present (Clause) 3868 and then not Addressable (Component_Size (FS)) 3869 then 3870 Error_Msg_NE 3871 ("non-atomic components of type& may not be " 3872 & "accessible by separate tasks??", Clause, Arr); 3873 3874 if Has_Component_Size_Clause (Arr) then 3875 Error_Msg_Sloc := Sloc (Get_Attribute_Definition_Clause 3876 (FS, Attribute_Component_Size)); 3877 Error_Msg_N ("\because of component size clause#??", Clause); 3878 3879 elsif Has_Pragma_Pack (Arr) then 3880 Error_Msg_Sloc := Sloc (Get_Rep_Pragma (FS, Name_Pack)); 3881 Error_Msg_N ("\because of pragma Pack#??", Clause); 3882 end if; 3883 end if; 3884 3885 -- Check for scalar storage order 3886 3887 declare 3888 Dummy : Boolean; 3889 begin 3890 Check_Component_Storage_Order 3891 (Encl_Type => Arr, 3892 Comp => Empty, 3893 ADC => Get_Attribute_Definition_Clause 3894 (First_Subtype (Arr), 3895 Attribute_Scalar_Storage_Order), 3896 Comp_ADC_Present => Dummy); 3897 end; 3898 3899 -- Processing that is done only for subtypes 3900 3901 else 3902 -- Acquire alignment from base type. Known_Alignment of the base 3903 -- type is False for Wide_String, for example. 3904 3905 if not Known_Alignment (Arr) 3906 and then Known_Alignment (Base_Type (Arr)) 3907 then 3908 Set_Alignment (Arr, Alignment (Base_Type (Arr))); 3909 Adjust_Esize_Alignment (Arr); 3910 end if; 3911 end if; 3912 3913 -- Specific checks for bit-packed arrays 3914 3915 if Is_Bit_Packed_Array (Arr) then 3916 3917 -- Check number of elements for bit-packed arrays that come from 3918 -- source and have compile time known ranges. The bit-packed 3919 -- arrays circuitry does not support arrays with more than 3920 -- Integer'Last + 1 elements, and when this restriction is 3921 -- violated, causes incorrect data access. 3922 3923 -- For the case where this is not compile time known, a run-time 3924 -- check should be generated??? 3925 3926 if Comes_From_Source (Arr) and then Is_Constrained (Arr) then 3927 declare 3928 Elmts : Uint; 3929 Index : Node_Id; 3930 Ilen : Node_Id; 3931 Ityp : Entity_Id; 3932 3933 begin 3934 Elmts := Uint_1; 3935 Index := First_Index (Arr); 3936 while Present (Index) loop 3937 Ityp := Etype (Index); 3938 3939 -- Never generate an error if any index is of a generic 3940 -- type. We will check this in instances. 3941 3942 if Is_Generic_Type (Ityp) then 3943 Elmts := Uint_0; 3944 exit; 3945 end if; 3946 3947 Ilen := 3948 Make_Attribute_Reference (Loc, 3949 Prefix => New_Occurrence_Of (Ityp, Loc), 3950 Attribute_Name => Name_Range_Length); 3951 Analyze_And_Resolve (Ilen); 3952 3953 -- No attempt is made to check number of elements if not 3954 -- compile time known. 3955 3956 if Nkind (Ilen) /= N_Integer_Literal then 3957 Elmts := Uint_0; 3958 exit; 3959 end if; 3960 3961 Elmts := Elmts * Intval (Ilen); 3962 Next_Index (Index); 3963 end loop; 3964 3965 if Elmts > Intval (High_Bound 3966 (Scalar_Range (Standard_Integer))) + 1 3967 then 3968 Error_Msg_N 3969 ("bit packed array type may not have " 3970 & "more than Integer''Last+1 elements", Arr); 3971 end if; 3972 end; 3973 end if; 3974 3975 -- Check size 3976 3977 if Known_RM_Size (Arr) then 3978 declare 3979 SizC : constant Node_Id := Size_Clause (Arr); 3980 Discard : Boolean; 3981 3982 begin 3983 -- It is not clear if it is possible to have no size clause 3984 -- at this stage, but it is not worth worrying about. Post 3985 -- error on the entity name in the size clause if present, 3986 -- else on the type entity itself. 3987 3988 if Present (SizC) then 3989 Check_Size (Name (SizC), Arr, RM_Size (Arr), Discard); 3990 else 3991 Check_Size (Arr, Arr, RM_Size (Arr), Discard); 3992 end if; 3993 end; 3994 end if; 3995 end if; 3996 3997 -- If any of the index types was an enumeration type with a non- 3998 -- standard rep clause, then we indicate that the array type is 3999 -- always packed (even if it is not bit-packed). 4000 4001 if Non_Standard_Enum then 4002 Set_Has_Non_Standard_Rep (Base_Type (Arr)); 4003 Set_Is_Packed (Base_Type (Arr)); 4004 end if; 4005 4006 Set_Component_Alignment_If_Not_Set (Arr); 4007 4008 -- If the array is packed and bit-packed or packed to eliminate holes 4009 -- in the non-contiguous enumeration index types, we must create the 4010 -- packed array type to be used to actually implement the type. This 4011 -- is only needed for real array types (not for string literal types, 4012 -- since they are present only for the front end). 4013 4014 if Is_Packed (Arr) 4015 and then (Is_Bit_Packed_Array (Arr) or else Non_Standard_Enum) 4016 and then Ekind (Arr) /= E_String_Literal_Subtype 4017 then 4018 Create_Packed_Array_Impl_Type (Arr); 4019 Freeze_And_Append (Packed_Array_Impl_Type (Arr), N, Result); 4020 4021 -- Make sure that we have the necessary routines to implement the 4022 -- packing, and complain now if not. Note that we only test this 4023 -- for constrained array types. 4024 4025 if Is_Constrained (Arr) 4026 and then Is_Bit_Packed_Array (Arr) 4027 and then Present (Packed_Array_Impl_Type (Arr)) 4028 and then Is_Array_Type (Packed_Array_Impl_Type (Arr)) 4029 then 4030 declare 4031 CS : constant Uint := Component_Size (Arr); 4032 RE : constant RE_Id := Get_Id (UI_To_Int (CS)); 4033 4034 begin 4035 if RE /= RE_Null 4036 and then not RTE_Available (RE) 4037 then 4038 Error_Msg_CRT 4039 ("packing of " & UI_Image (CS) & "-bit components", 4040 First_Subtype (Etype (Arr))); 4041 4042 -- Cancel the packing 4043 4044 Set_Is_Packed (Base_Type (Arr), False); 4045 Set_Is_Bit_Packed_Array (Base_Type (Arr), False); 4046 Set_Packed_Array_Impl_Type (Arr, Empty); 4047 goto Skip_Packed; 4048 end if; 4049 end; 4050 end if; 4051 4052 -- Size information of packed array type is copied to the array 4053 -- type, since this is really the representation. But do not 4054 -- override explicit existing size values. If the ancestor subtype 4055 -- is constrained the Packed_Array_Impl_Type will be inherited 4056 -- from it, but the size may have been provided already, and 4057 -- must not be overridden either. 4058 4059 if not Has_Size_Clause (Arr) 4060 and then 4061 (No (Ancestor_Subtype (Arr)) 4062 or else not Has_Size_Clause (Ancestor_Subtype (Arr))) 4063 then 4064 Copy_Esize (To => Arr, From => Packed_Array_Impl_Type (Arr)); 4065 Copy_RM_Size (To => Arr, From => Packed_Array_Impl_Type (Arr)); 4066 end if; 4067 4068 if not Has_Alignment_Clause (Arr) then 4069 Copy_Alignment 4070 (To => Arr, From => Packed_Array_Impl_Type (Arr)); 4071 end if; 4072 end if; 4073 4074 <<Skip_Packed>> 4075 4076 -- A Ghost type cannot have a component of protected or task type 4077 -- (SPARK RM 6.9(19)). 4078 4079 if Is_Ghost_Entity (Arr) and then Is_Concurrent_Type (Ctyp) then 4080 Error_Msg_N 4081 ("ghost array type & cannot have concurrent component type", 4082 Arr); 4083 end if; 4084 end Freeze_Array_Type; 4085 4086 ------------------------------- 4087 -- Freeze_Object_Declaration -- 4088 ------------------------------- 4089 4090 procedure Freeze_Object_Declaration (E : Entity_Id) is 4091 procedure Check_Large_Modular_Array (Typ : Entity_Id); 4092 -- Check that the size of array type Typ can be computed without 4093 -- overflow, and generates a Storage_Error otherwise. This is only 4094 -- relevant for array types whose index has System_Max_Integer_Size 4095 -- bits, where wrap-around arithmetic might yield a meaningless value 4096 -- for the length of the array, or its corresponding attribute. 4097 4098 procedure Check_Pragma_Thread_Local_Storage (Var_Id : Entity_Id); 4099 -- Ensure that the initialization state of variable Var_Id subject 4100 -- to pragma Thread_Local_Storage agrees with the semantics of the 4101 -- pragma. 4102 4103 function Has_Default_Initialization 4104 (Obj_Id : Entity_Id) return Boolean; 4105 -- Determine whether object Obj_Id default initialized 4106 4107 ------------------------------- 4108 -- Check_Large_Modular_Array -- 4109 ------------------------------- 4110 4111 procedure Check_Large_Modular_Array (Typ : Entity_Id) is 4112 Obj_Loc : constant Source_Ptr := Sloc (E); 4113 Idx_Typ : Entity_Id; 4114 4115 begin 4116 -- Nothing to do when expansion is disabled because this routine 4117 -- generates a runtime check. 4118 4119 if not Expander_Active then 4120 return; 4121 4122 -- Nothing to do for String literal subtypes because their index 4123 -- cannot be a modular type. 4124 4125 elsif Ekind (Typ) = E_String_Literal_Subtype then 4126 return; 4127 4128 -- Nothing to do for an imported object because the object will 4129 -- be created on the exporting side. 4130 4131 elsif Is_Imported (E) then 4132 return; 4133 4134 -- Nothing to do for unconstrained array types. This case arises 4135 -- when the object declaration is illegal. 4136 4137 elsif not Is_Constrained (Typ) then 4138 return; 4139 end if; 4140 4141 Idx_Typ := Etype (First_Index (Typ)); 4142 4143 -- To prevent arithmetic overflow with large values, we raise 4144 -- Storage_Error under the following guard: 4145 -- 4146 -- (Arr'Last / 2 - Arr'First / 2) > (2 ** 30) 4147 -- 4148 -- This takes care of the boundary case, but it is preferable to 4149 -- use a smaller limit, because even on 64-bit architectures an 4150 -- array of more than 2 ** 30 bytes is likely to raise 4151 -- Storage_Error. 4152 4153 if Is_Modular_Integer_Type (Idx_Typ) 4154 and then RM_Size (Idx_Typ) = RM_Size (Standard_Long_Long_Integer) 4155 then 4156 Insert_Action (Declaration_Node (E), 4157 Make_Raise_Storage_Error (Obj_Loc, 4158 Condition => 4159 Make_Op_Ge (Obj_Loc, 4160 Left_Opnd => 4161 Make_Op_Subtract (Obj_Loc, 4162 Left_Opnd => 4163 Make_Op_Divide (Obj_Loc, 4164 Left_Opnd => 4165 Make_Attribute_Reference (Obj_Loc, 4166 Prefix => 4167 New_Occurrence_Of (Typ, Obj_Loc), 4168 Attribute_Name => Name_Last), 4169 Right_Opnd => 4170 Make_Integer_Literal (Obj_Loc, Uint_2)), 4171 Right_Opnd => 4172 Make_Op_Divide (Obj_Loc, 4173 Left_Opnd => 4174 Make_Attribute_Reference (Obj_Loc, 4175 Prefix => 4176 New_Occurrence_Of (Typ, Obj_Loc), 4177 Attribute_Name => Name_First), 4178 Right_Opnd => 4179 Make_Integer_Literal (Obj_Loc, Uint_2))), 4180 Right_Opnd => 4181 Make_Integer_Literal (Obj_Loc, (Uint_2 ** 30))), 4182 Reason => SE_Object_Too_Large)); 4183 end if; 4184 end Check_Large_Modular_Array; 4185 4186 --------------------------------------- 4187 -- Check_Pragma_Thread_Local_Storage -- 4188 --------------------------------------- 4189 4190 procedure Check_Pragma_Thread_Local_Storage (Var_Id : Entity_Id) is 4191 function Has_Incompatible_Initialization 4192 (Var_Decl : Node_Id) return Boolean; 4193 -- Determine whether variable Var_Id with declaration Var_Decl is 4194 -- initialized with a value that violates the semantics of pragma 4195 -- Thread_Local_Storage. 4196 4197 ------------------------------------- 4198 -- Has_Incompatible_Initialization -- 4199 ------------------------------------- 4200 4201 function Has_Incompatible_Initialization 4202 (Var_Decl : Node_Id) return Boolean 4203 is 4204 Init_Expr : constant Node_Id := Expression (Var_Decl); 4205 4206 begin 4207 -- The variable is default-initialized. This directly violates 4208 -- the semantics of the pragma. 4209 4210 if Has_Default_Initialization (Var_Id) then 4211 return True; 4212 4213 -- The variable has explicit initialization. In this case only 4214 -- a handful of values satisfy the semantics of the pragma. 4215 4216 elsif Has_Init_Expression (Var_Decl) 4217 and then Present (Init_Expr) 4218 then 4219 -- "null" is a legal form of initialization 4220 4221 if Nkind (Init_Expr) = N_Null then 4222 return False; 4223 4224 -- A static expression is a legal form of initialization 4225 4226 elsif Is_Static_Expression (Init_Expr) then 4227 return False; 4228 4229 -- A static aggregate is a legal form of initialization 4230 4231 elsif Nkind (Init_Expr) = N_Aggregate 4232 and then Compile_Time_Known_Aggregate (Init_Expr) 4233 then 4234 return False; 4235 4236 -- All other initialization expressions violate the semantic 4237 -- of the pragma. 4238 4239 else 4240 return True; 4241 end if; 4242 4243 -- The variable lacks any kind of initialization, which agrees 4244 -- with the semantics of the pragma. 4245 4246 else 4247 return False; 4248 end if; 4249 end Has_Incompatible_Initialization; 4250 4251 -- Local declarations 4252 4253 Var_Decl : constant Node_Id := Declaration_Node (Var_Id); 4254 4255 -- Start of processing for Check_Pragma_Thread_Local_Storage 4256 4257 begin 4258 -- A variable whose initialization is suppressed lacks any kind of 4259 -- initialization. 4260 4261 if Suppress_Initialization (Var_Id) then 4262 null; 4263 4264 -- The variable has default initialization, or is explicitly 4265 -- initialized to a value other than null, static expression, 4266 -- or a static aggregate. 4267 4268 elsif Has_Incompatible_Initialization (Var_Decl) then 4269 Error_Msg_NE 4270 ("Thread_Local_Storage variable& is improperly initialized", 4271 Var_Decl, Var_Id); 4272 Error_Msg_NE 4273 ("\only allowed initialization is explicit NULL, static " 4274 & "expression or static aggregate", Var_Decl, Var_Id); 4275 end if; 4276 end Check_Pragma_Thread_Local_Storage; 4277 4278 -------------------------------- 4279 -- Has_Default_Initialization -- 4280 -------------------------------- 4281 4282 function Has_Default_Initialization 4283 (Obj_Id : Entity_Id) return Boolean 4284 is 4285 Obj_Decl : constant Node_Id := Declaration_Node (Obj_Id); 4286 Obj_Typ : constant Entity_Id := Etype (Obj_Id); 4287 4288 begin 4289 return 4290 Comes_From_Source (Obj_Id) 4291 and then not Is_Imported (Obj_Id) 4292 and then not Has_Init_Expression (Obj_Decl) 4293 and then 4294 ((Has_Non_Null_Base_Init_Proc (Obj_Typ) 4295 and then not No_Initialization (Obj_Decl) 4296 and then not Initialization_Suppressed (Obj_Typ)) 4297 or else 4298 (Needs_Simple_Initialization (Obj_Typ) 4299 and then not Is_Internal (Obj_Id))); 4300 end Has_Default_Initialization; 4301 4302 -- Local variables 4303 4304 Typ : constant Entity_Id := Etype (E); 4305 Def : Node_Id; 4306 4307 -- Start of processing for Freeze_Object_Declaration 4308 4309 begin 4310 -- Abstract type allowed only for C++ imported variables or constants 4311 4312 -- Note: we inhibit this check for objects that do not come from 4313 -- source because there is at least one case (the expansion of 4314 -- x'Class'Input where x is abstract) where we legitimately 4315 -- generate an abstract object. 4316 4317 if Is_Abstract_Type (Typ) 4318 and then Comes_From_Source (Parent (E)) 4319 and then not (Is_Imported (E) and then Is_CPP_Class (Typ)) 4320 then 4321 Def := Object_Definition (Parent (E)); 4322 4323 Error_Msg_N ("type of object cannot be abstract", Def); 4324 4325 if Is_CPP_Class (Etype (E)) then 4326 Error_Msg_NE ("\} may need a cpp_constructor", Def, Typ); 4327 4328 elsif Present (Expression (Parent (E))) then 4329 Error_Msg_N -- CODEFIX 4330 ("\maybe a class-wide type was meant", Def); 4331 end if; 4332 end if; 4333 4334 -- For object created by object declaration, perform required 4335 -- categorization (preelaborate and pure) checks. Defer these 4336 -- checks to freeze time since pragma Import inhibits default 4337 -- initialization and thus pragma Import affects these checks. 4338 4339 Validate_Object_Declaration (Declaration_Node (E)); 4340 4341 -- If there is an address clause, check that it is valid and if need 4342 -- be move initialization to the freeze node. 4343 4344 Check_Address_Clause (E); 4345 4346 -- Similar processing is needed for aspects that may affect object 4347 -- layout, like Address, if there is an initialization expression. 4348 -- We don't do this if there is a pragma Linker_Section, because it 4349 -- would prevent the back end from statically initializing the 4350 -- object; we don't want elaboration code in that case. 4351 4352 if Has_Delayed_Aspects (E) 4353 and then Expander_Active 4354 and then Is_Array_Type (Typ) 4355 and then Present (Expression (Declaration_Node (E))) 4356 and then No (Linker_Section_Pragma (E)) 4357 then 4358 declare 4359 Decl : constant Node_Id := Declaration_Node (E); 4360 Lhs : constant Node_Id := New_Occurrence_Of (E, Loc); 4361 4362 begin 4363 -- Capture initialization value at point of declaration, and 4364 -- make explicit assignment legal, because object may be a 4365 -- constant. 4366 4367 Remove_Side_Effects (Expression (Decl)); 4368 Set_Assignment_OK (Lhs); 4369 4370 -- Move initialization to freeze actions 4371 4372 Append_Freeze_Action (E, 4373 Make_Assignment_Statement (Loc, 4374 Name => Lhs, 4375 Expression => Expression (Decl))); 4376 4377 Set_No_Initialization (Decl); 4378 -- Set_Is_Frozen (E, False); 4379 end; 4380 end if; 4381 4382 -- Reset Is_True_Constant for non-constant aliased object. We 4383 -- consider that the fact that a non-constant object is aliased may 4384 -- indicate that some funny business is going on, e.g. an aliased 4385 -- object is passed by reference to a procedure which captures the 4386 -- address of the object, which is later used to assign a new value, 4387 -- even though the compiler thinks that it is not modified. Such 4388 -- code is highly dubious, but we choose to make it "work" for 4389 -- non-constant aliased objects. 4390 4391 -- Note that we used to do this for all aliased objects, whether or 4392 -- not constant, but this caused anomalies down the line because we 4393 -- ended up with static objects that were not Is_True_Constant. Not 4394 -- resetting Is_True_Constant for (aliased) constant objects ensures 4395 -- that this anomaly never occurs. 4396 4397 -- However, we don't do that for internal entities. We figure that if 4398 -- we deliberately set Is_True_Constant for an internal entity, e.g. 4399 -- a dispatch table entry, then we mean it. 4400 4401 if Ekind (E) /= E_Constant 4402 and then (Is_Aliased (E) or else Is_Aliased (Typ)) 4403 and then not Is_Internal_Name (Chars (E)) 4404 then 4405 Set_Is_True_Constant (E, False); 4406 end if; 4407 4408 -- If the object needs any kind of default initialization, an error 4409 -- must be issued if No_Default_Initialization applies. The check 4410 -- doesn't apply to imported objects, which are not ever default 4411 -- initialized, and is why the check is deferred until freezing, at 4412 -- which point we know if Import applies. Deferred constants are also 4413 -- exempted from this test because their completion is explicit, or 4414 -- through an import pragma. 4415 4416 if Ekind (E) = E_Constant and then Present (Full_View (E)) then 4417 null; 4418 4419 elsif Has_Default_Initialization (E) then 4420 Check_Restriction 4421 (No_Default_Initialization, Declaration_Node (E)); 4422 end if; 4423 4424 -- Ensure that a variable subject to pragma Thread_Local_Storage 4425 -- 4426 -- * Lacks default initialization, or 4427 -- 4428 -- * The initialization expression is either "null", a static 4429 -- constant, or a compile-time known aggregate. 4430 4431 if Has_Pragma_Thread_Local_Storage (E) then 4432 Check_Pragma_Thread_Local_Storage (E); 4433 end if; 4434 4435 -- For imported objects, set Is_Public unless there is also an 4436 -- address clause, which means that there is no external symbol 4437 -- needed for the Import (Is_Public may still be set for other 4438 -- unrelated reasons). Note that we delayed this processing 4439 -- till freeze time so that we can be sure not to set the flag 4440 -- if there is an address clause. If there is such a clause, 4441 -- then the only purpose of the Import pragma is to suppress 4442 -- implicit initialization. 4443 4444 if Is_Imported (E) and then No (Address_Clause (E)) then 4445 Set_Is_Public (E); 4446 end if; 4447 4448 -- For source objects that are not Imported and are library level, if 4449 -- no linker section pragma was given inherit the appropriate linker 4450 -- section from the corresponding type. 4451 4452 if Comes_From_Source (E) 4453 and then not Is_Imported (E) 4454 and then Is_Library_Level_Entity (E) 4455 and then No (Linker_Section_Pragma (E)) 4456 then 4457 Set_Linker_Section_Pragma (E, Linker_Section_Pragma (Typ)); 4458 end if; 4459 4460 -- For convention C objects of an enumeration type, warn if the size 4461 -- is not integer size and no explicit size given. Skip warning for 4462 -- Boolean and Character, and assume programmer expects 8-bit sizes 4463 -- for these cases. 4464 4465 if (Convention (E) = Convention_C 4466 or else 4467 Convention (E) = Convention_CPP) 4468 and then Is_Enumeration_Type (Typ) 4469 and then not Is_Character_Type (Typ) 4470 and then not Is_Boolean_Type (Typ) 4471 and then Esize (Typ) < Standard_Integer_Size 4472 and then not Has_Size_Clause (E) 4473 then 4474 Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size); 4475 Error_Msg_N 4476 ("??convention C enumeration object has size less than ^", E); 4477 Error_Msg_N ("\??use explicit size clause to set size", E); 4478 end if; 4479 4480 -- Declaring too big an array in disabled ghost code is OK 4481 4482 if Is_Array_Type (Typ) and then not Is_Ignored_Ghost_Entity (E) then 4483 Check_Large_Modular_Array (Typ); 4484 end if; 4485 end Freeze_Object_Declaration; 4486 4487 ----------------------------- 4488 -- Freeze_Generic_Entities -- 4489 ----------------------------- 4490 4491 function Freeze_Generic_Entities (Pack : Entity_Id) return List_Id is 4492 E : Entity_Id; 4493 F : Node_Id; 4494 Flist : List_Id; 4495 4496 begin 4497 Flist := New_List; 4498 E := First_Entity (Pack); 4499 while Present (E) loop 4500 if Is_Type (E) and then not Is_Generic_Type (E) then 4501 F := Make_Freeze_Generic_Entity (Sloc (Pack)); 4502 Set_Entity (F, E); 4503 Append_To (Flist, F); 4504 4505 elsif Ekind (E) = E_Generic_Package then 4506 Append_List_To (Flist, Freeze_Generic_Entities (E)); 4507 end if; 4508 4509 Next_Entity (E); 4510 end loop; 4511 4512 return Flist; 4513 end Freeze_Generic_Entities; 4514 4515 -------------------- 4516 -- Freeze_Profile -- 4517 -------------------- 4518 4519 function Freeze_Profile (E : Entity_Id) return Boolean is 4520 F_Type : Entity_Id; 4521 R_Type : Entity_Id; 4522 Warn_Node : Node_Id; 4523 4524 begin 4525 -- Loop through formals 4526 4527 Formal := First_Formal (E); 4528 while Present (Formal) loop 4529 F_Type := Etype (Formal); 4530 4531 -- AI05-0151: incomplete types can appear in a profile. By the 4532 -- time the entity is frozen, the full view must be available, 4533 -- unless it is a limited view. 4534 4535 if Is_Incomplete_Type (F_Type) 4536 and then Present (Full_View (F_Type)) 4537 and then not From_Limited_With (F_Type) 4538 then 4539 F_Type := Full_View (F_Type); 4540 Set_Etype (Formal, F_Type); 4541 end if; 4542 4543 if not From_Limited_With (F_Type) 4544 and then Should_Freeze_Type (F_Type, E) 4545 then 4546 Freeze_And_Append (F_Type, N, Result); 4547 end if; 4548 4549 if Is_Private_Type (F_Type) 4550 and then Is_Private_Type (Base_Type (F_Type)) 4551 and then No (Full_View (Base_Type (F_Type))) 4552 and then not Is_Generic_Type (F_Type) 4553 and then not Is_Derived_Type (F_Type) 4554 then 4555 -- If the type of a formal is incomplete, subprogram is being 4556 -- frozen prematurely. Within an instance (but not within a 4557 -- wrapper package) this is an artifact of our need to regard 4558 -- the end of an instantiation as a freeze point. Otherwise it 4559 -- is a definite error. 4560 4561 if In_Instance then 4562 Set_Is_Frozen (E, False); 4563 Result := No_List; 4564 return False; 4565 4566 elsif not After_Last_Declaration 4567 and then not Freezing_Library_Level_Tagged_Type 4568 then 4569 Error_Msg_NE 4570 ("type & must be fully defined before this point", 4571 N, 4572 F_Type); 4573 end if; 4574 end if; 4575 4576 -- Check suspicious parameter for C function. These tests apply 4577 -- only to exported/imported subprograms. 4578 4579 if Warn_On_Export_Import 4580 and then Comes_From_Source (E) 4581 and then Convention (E) in Convention_C_Family 4582 and then (Is_Imported (E) or else Is_Exported (E)) 4583 and then Convention (E) /= Convention (Formal) 4584 and then not Has_Warnings_Off (E) 4585 and then not Has_Warnings_Off (F_Type) 4586 and then not Has_Warnings_Off (Formal) 4587 then 4588 -- Qualify mention of formals with subprogram name 4589 4590 Error_Msg_Qual_Level := 1; 4591 4592 -- Check suspicious use of fat C pointer, but do not emit 4593 -- a warning on an access to subprogram when unnesting is 4594 -- active. 4595 4596 if Is_Access_Type (F_Type) 4597 and then Known_Esize (F_Type) 4598 and then Esize (F_Type) > Ttypes.System_Address_Size 4599 and then (not Unnest_Subprogram_Mode 4600 or else not Is_Access_Subprogram_Type (F_Type)) 4601 then 4602 Error_Msg_N 4603 ("?x?type of & does not correspond to C pointer!", Formal); 4604 4605 -- Check suspicious return of boolean 4606 4607 elsif Root_Type (F_Type) = Standard_Boolean 4608 and then Convention (F_Type) = Convention_Ada 4609 and then not Has_Warnings_Off (F_Type) 4610 and then not Has_Size_Clause (F_Type) 4611 then 4612 Error_Msg_N 4613 ("& is an 8-bit Ada Boolean?x?", Formal); 4614 Error_Msg_N 4615 ("\use appropriate corresponding type in C " 4616 & "(e.g. char)?x?", Formal); 4617 4618 -- Check suspicious tagged type 4619 4620 elsif (Is_Tagged_Type (F_Type) 4621 or else 4622 (Is_Access_Type (F_Type) 4623 and then Is_Tagged_Type (Designated_Type (F_Type)))) 4624 and then Convention (E) = Convention_C 4625 then 4626 Error_Msg_N 4627 ("?x?& involves a tagged type which does not " 4628 & "correspond to any C type!", Formal); 4629 4630 -- Check wrong convention subprogram pointer 4631 4632 elsif Ekind (F_Type) = E_Access_Subprogram_Type 4633 and then not Has_Foreign_Convention (F_Type) 4634 then 4635 Error_Msg_N 4636 ("?x?subprogram pointer & should " 4637 & "have foreign convention!", Formal); 4638 Error_Msg_Sloc := Sloc (F_Type); 4639 Error_Msg_NE 4640 ("\?x?add Convention pragma to declaration of &#", 4641 Formal, F_Type); 4642 end if; 4643 4644 -- Turn off name qualification after message output 4645 4646 Error_Msg_Qual_Level := 0; 4647 end if; 4648 4649 -- Check for unconstrained array in exported foreign convention 4650 -- case. 4651 4652 if Has_Foreign_Convention (E) 4653 and then not Is_Imported (E) 4654 and then Is_Array_Type (F_Type) 4655 and then not Is_Constrained (F_Type) 4656 and then Warn_On_Export_Import 4657 then 4658 Error_Msg_Qual_Level := 1; 4659 4660 -- If this is an inherited operation, place the warning on 4661 -- the derived type declaration, rather than on the original 4662 -- subprogram. 4663 4664 if Nkind (Original_Node (Parent (E))) = N_Full_Type_Declaration 4665 then 4666 Warn_Node := Parent (E); 4667 4668 if Formal = First_Formal (E) then 4669 Error_Msg_NE ("??in inherited operation&", Warn_Node, E); 4670 end if; 4671 else 4672 Warn_Node := Formal; 4673 end if; 4674 4675 Error_Msg_NE ("?x?type of argument& is unconstrained array", 4676 Warn_Node, Formal); 4677 Error_Msg_N ("\?x?foreign caller must pass bounds explicitly", 4678 Warn_Node); 4679 Error_Msg_Qual_Level := 0; 4680 end if; 4681 4682 if not From_Limited_With (F_Type) then 4683 if Is_Access_Type (F_Type) then 4684 F_Type := Designated_Type (F_Type); 4685 end if; 4686 4687 -- If the formal is an anonymous_access_to_subprogram 4688 -- freeze the subprogram type as well, to prevent 4689 -- scope anomalies in gigi, because there is no other 4690 -- clear point at which it could be frozen. 4691 4692 if Is_Itype (Etype (Formal)) 4693 and then Ekind (F_Type) = E_Subprogram_Type 4694 then 4695 Freeze_And_Append (F_Type, N, Result); 4696 end if; 4697 end if; 4698 4699 Next_Formal (Formal); 4700 end loop; 4701 4702 -- Case of function: similar checks on return type 4703 4704 if Ekind (E) = E_Function then 4705 4706 -- Freeze return type 4707 4708 R_Type := Etype (E); 4709 4710 -- AI05-0151: the return type may have been incomplete at the 4711 -- point of declaration. Replace it with the full view, unless the 4712 -- current type is a limited view. In that case the full view is 4713 -- in a different unit, and gigi finds the non-limited view after 4714 -- the other unit is elaborated. 4715 4716 if Ekind (R_Type) = E_Incomplete_Type 4717 and then Present (Full_View (R_Type)) 4718 and then not From_Limited_With (R_Type) 4719 then 4720 R_Type := Full_View (R_Type); 4721 Set_Etype (E, R_Type); 4722 end if; 4723 4724 if Should_Freeze_Type (R_Type, E) then 4725 Freeze_And_Append (R_Type, N, Result); 4726 end if; 4727 4728 -- Check suspicious return type for C function 4729 4730 if Warn_On_Export_Import 4731 and then Comes_From_Source (E) 4732 and then Convention (E) in Convention_C_Family 4733 and then (Is_Imported (E) or else Is_Exported (E)) 4734 then 4735 -- Check suspicious return of fat C pointer 4736 4737 if Is_Access_Type (R_Type) 4738 and then Known_Esize (R_Type) 4739 and then Esize (R_Type) > Ttypes.System_Address_Size 4740 and then not Has_Warnings_Off (E) 4741 and then not Has_Warnings_Off (R_Type) 4742 then 4743 Error_Msg_N 4744 ("?x?return type of& does not correspond to C pointer!", 4745 E); 4746 4747 -- Check suspicious return of boolean 4748 4749 elsif Root_Type (R_Type) = Standard_Boolean 4750 and then Convention (R_Type) = Convention_Ada 4751 and then not Has_Warnings_Off (E) 4752 and then not Has_Warnings_Off (R_Type) 4753 and then not Has_Size_Clause (R_Type) 4754 then 4755 declare 4756 N : constant Node_Id := 4757 Result_Definition (Declaration_Node (E)); 4758 begin 4759 Error_Msg_NE 4760 ("return type of & is an 8-bit Ada Boolean?x?", N, E); 4761 Error_Msg_NE 4762 ("\use appropriate corresponding type in C " 4763 & "(e.g. char)?x?", N, E); 4764 end; 4765 4766 -- Check suspicious return tagged type 4767 4768 elsif (Is_Tagged_Type (R_Type) 4769 or else (Is_Access_Type (R_Type) 4770 and then 4771 Is_Tagged_Type 4772 (Designated_Type (R_Type)))) 4773 and then Convention (E) = Convention_C 4774 and then not Has_Warnings_Off (E) 4775 and then not Has_Warnings_Off (R_Type) 4776 then 4777 Error_Msg_N ("?x?return type of & does not " 4778 & "correspond to C type!", E); 4779 4780 -- Check return of wrong convention subprogram pointer 4781 4782 elsif Ekind (R_Type) = E_Access_Subprogram_Type 4783 and then not Has_Foreign_Convention (R_Type) 4784 and then not Has_Warnings_Off (E) 4785 and then not Has_Warnings_Off (R_Type) 4786 then 4787 Error_Msg_N ("?x?& should return a foreign " 4788 & "convention subprogram pointer", E); 4789 Error_Msg_Sloc := Sloc (R_Type); 4790 Error_Msg_NE 4791 ("\?x?add Convention pragma to declaration of& #", 4792 E, R_Type); 4793 end if; 4794 end if; 4795 4796 -- Give warning for suspicious return of a result of an 4797 -- unconstrained array type in a foreign convention function. 4798 4799 if Has_Foreign_Convention (E) 4800 4801 -- We are looking for a return of unconstrained array 4802 4803 and then Is_Array_Type (R_Type) 4804 and then not Is_Constrained (R_Type) 4805 4806 -- Exclude imported routines, the warning does not belong on 4807 -- the import, but rather on the routine definition. 4808 4809 and then not Is_Imported (E) 4810 4811 -- Check that general warning is enabled, and that it is not 4812 -- suppressed for this particular case. 4813 4814 and then Warn_On_Export_Import 4815 and then not Has_Warnings_Off (E) 4816 and then not Has_Warnings_Off (R_Type) 4817 then 4818 Error_Msg_N 4819 ("?x?foreign convention function& should not return " 4820 & "unconstrained array!", E); 4821 end if; 4822 end if; 4823 4824 -- Check suspicious use of Import in pure unit (cases where the RM 4825 -- allows calls to be omitted). 4826 4827 if Is_Imported (E) 4828 4829 -- It might be suspicious if the compilation unit has the Pure 4830 -- aspect/pragma. 4831 4832 and then Has_Pragma_Pure (Cunit_Entity (Current_Sem_Unit)) 4833 4834 -- The RM allows omission of calls only in the case of 4835 -- library-level subprograms (see RM-10.2.1(18)). 4836 4837 and then Is_Library_Level_Entity (E) 4838 4839 -- Ignore internally generated entity. This happens in some cases 4840 -- of subprograms in specs, where we generate an implied body. 4841 4842 and then Comes_From_Source (Import_Pragma (E)) 4843 4844 -- Assume run-time knows what it is doing 4845 4846 and then not GNAT_Mode 4847 4848 -- Assume explicit Pure_Function means import is pure 4849 4850 and then not Has_Pragma_Pure_Function (E) 4851 4852 -- Don't need warning in relaxed semantics mode 4853 4854 and then not Relaxed_RM_Semantics 4855 4856 -- Assume convention Intrinsic is OK, since this is specialized. 4857 -- This deals with the DEC unit current_exception.ads 4858 4859 and then Convention (E) /= Convention_Intrinsic 4860 4861 -- Assume that ASM interface knows what it is doing 4862 4863 and then Convention (E) /= Convention_Assembler 4864 then 4865 Error_Msg_N 4866 ("pragma Import in Pure unit??", Import_Pragma (E)); 4867 Error_Msg_NE 4868 ("\calls to & may be omitted (RM 10.2.1(18/3))??", 4869 Import_Pragma (E), E); 4870 end if; 4871 4872 return True; 4873 end Freeze_Profile; 4874 4875 ------------------------ 4876 -- Freeze_Record_Type -- 4877 ------------------------ 4878 4879 procedure Freeze_Record_Type (Rec : Entity_Id) is 4880 ADC : Node_Id; 4881 Comp : Entity_Id; 4882 IR : Node_Id; 4883 Prev : Entity_Id; 4884 4885 Junk : Boolean; 4886 pragma Warnings (Off, Junk); 4887 4888 Aliased_Component : Boolean := False; 4889 -- Set True if we find at least one component which is aliased. This 4890 -- is used to prevent Implicit_Packing of the record, since packing 4891 -- cannot modify the size of alignment of an aliased component. 4892 4893 All_Elem_Components : Boolean := True; 4894 -- True if all components are of a type whose underlying type is 4895 -- elementary. 4896 4897 All_Sized_Components : Boolean := True; 4898 -- True if all components have a known RM_Size 4899 4900 All_Storage_Unit_Components : Boolean := True; 4901 -- True if all components have an RM_Size that is a multiple of the 4902 -- storage unit. 4903 4904 Elem_Component_Total_Esize : Uint := Uint_0; 4905 -- Accumulates total Esize values of all elementary components. Used 4906 -- for processing of Implicit_Packing. 4907 4908 Placed_Component : Boolean := False; 4909 -- Set True if we find at least one component with a component 4910 -- clause (used to warn about useless Bit_Order pragmas, and also 4911 -- to detect cases where Implicit_Packing may have an effect). 4912 4913 Sized_Component_Total_RM_Size : Uint := Uint_0; 4914 -- Accumulates total RM_Size values of all sized components. Used 4915 -- for processing of Implicit_Packing. 4916 4917 Sized_Component_Total_Round_RM_Size : Uint := Uint_0; 4918 -- Accumulates total RM_Size values of all sized components, rounded 4919 -- individually to a multiple of the storage unit. 4920 4921 SSO_ADC : Node_Id; 4922 -- Scalar_Storage_Order attribute definition clause for the record 4923 4924 SSO_ADC_Component : Boolean := False; 4925 -- Set True if we find at least one component whose type has a 4926 -- Scalar_Storage_Order attribute definition clause. 4927 4928 Unplaced_Component : Boolean := False; 4929 -- Set True if we find at least one component with no component 4930 -- clause (used to warn about useless Pack pragmas). 4931 4932 procedure Check_Itype (Typ : Entity_Id); 4933 -- If the component subtype is an access to a constrained subtype of 4934 -- an already frozen type, make the subtype frozen as well. It might 4935 -- otherwise be frozen in the wrong scope, and a freeze node on 4936 -- subtype has no effect. Similarly, if the component subtype is a 4937 -- regular (not protected) access to subprogram, set the anonymous 4938 -- subprogram type to frozen as well, to prevent an out-of-scope 4939 -- freeze node at some eventual point of call. Protected operations 4940 -- are handled elsewhere. 4941 4942 procedure Freeze_Choices_In_Variant_Part (VP : Node_Id); 4943 -- Make sure that all types mentioned in Discrete_Choices of the 4944 -- variants referenceed by the Variant_Part VP are frozen. This is 4945 -- a recursive routine to deal with nested variants. 4946 4947 ----------------- 4948 -- Check_Itype -- 4949 ----------------- 4950 4951 procedure Check_Itype (Typ : Entity_Id) is 4952 Desig : constant Entity_Id := Designated_Type (Typ); 4953 4954 begin 4955 if not Is_Frozen (Desig) 4956 and then Is_Frozen (Base_Type (Desig)) 4957 then 4958 Set_Is_Frozen (Desig); 4959 4960 -- In addition, add an Itype_Reference to ensure that the 4961 -- access subtype is elaborated early enough. This cannot be 4962 -- done if the subtype may depend on discriminants. 4963 4964 if Ekind (Comp) = E_Component 4965 and then Is_Itype (Etype (Comp)) 4966 and then not Has_Discriminants (Rec) 4967 then 4968 IR := Make_Itype_Reference (Sloc (Comp)); 4969 Set_Itype (IR, Desig); 4970 Add_To_Result (IR); 4971 end if; 4972 4973 elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type 4974 and then Convention (Desig) /= Convention_Protected 4975 then 4976 Set_Is_Frozen (Desig); 4977 end if; 4978 end Check_Itype; 4979 4980 ------------------------------------ 4981 -- Freeze_Choices_In_Variant_Part -- 4982 ------------------------------------ 4983 4984 procedure Freeze_Choices_In_Variant_Part (VP : Node_Id) is 4985 pragma Assert (Nkind (VP) = N_Variant_Part); 4986 4987 Variant : Node_Id; 4988 Choice : Node_Id; 4989 CL : Node_Id; 4990 4991 begin 4992 -- Loop through variants 4993 4994 Variant := First_Non_Pragma (Variants (VP)); 4995 while Present (Variant) loop 4996 4997 -- Loop through choices, checking that all types are frozen 4998 4999 Choice := First_Non_Pragma (Discrete_Choices (Variant)); 5000 while Present (Choice) loop 5001 if Nkind (Choice) in N_Has_Etype 5002 and then Present (Etype (Choice)) 5003 then 5004 Freeze_And_Append (Etype (Choice), N, Result); 5005 end if; 5006 5007 Next_Non_Pragma (Choice); 5008 end loop; 5009 5010 -- Check for nested variant part to process 5011 5012 CL := Component_List (Variant); 5013 5014 if not Null_Present (CL) then 5015 if Present (Variant_Part (CL)) then 5016 Freeze_Choices_In_Variant_Part (Variant_Part (CL)); 5017 end if; 5018 end if; 5019 5020 Next_Non_Pragma (Variant); 5021 end loop; 5022 end Freeze_Choices_In_Variant_Part; 5023 5024 -- Start of processing for Freeze_Record_Type 5025 5026 begin 5027 -- Freeze components and embedded subtypes 5028 5029 Comp := First_Entity (Rec); 5030 Prev := Empty; 5031 while Present (Comp) loop 5032 if Is_Aliased (Comp) then 5033 Aliased_Component := True; 5034 end if; 5035 5036 -- Handle the component and discriminant case 5037 5038 if Ekind (Comp) in E_Component | E_Discriminant then 5039 declare 5040 CC : constant Node_Id := Component_Clause (Comp); 5041 5042 begin 5043 -- Freezing a record type freezes the type of each of its 5044 -- components. However, if the type of the component is 5045 -- part of this record, we do not want or need a separate 5046 -- Freeze_Node. Note that Is_Itype is wrong because that's 5047 -- also set in private type cases. We also can't check for 5048 -- the Scope being exactly Rec because of private types and 5049 -- record extensions. 5050 5051 if Is_Itype (Etype (Comp)) 5052 and then Is_Record_Type (Underlying_Type 5053 (Scope (Etype (Comp)))) 5054 then 5055 Undelay_Type (Etype (Comp)); 5056 end if; 5057 5058 Freeze_And_Append (Etype (Comp), N, Result); 5059 5060 -- Warn for pragma Pack overriding foreign convention 5061 5062 if Has_Foreign_Convention (Etype (Comp)) 5063 and then Has_Pragma_Pack (Rec) 5064 5065 -- Don't warn for aliased components, since override 5066 -- cannot happen in that case. 5067 5068 and then not Is_Aliased (Comp) 5069 then 5070 declare 5071 CN : constant Name_Id := 5072 Get_Convention_Name (Convention (Etype (Comp))); 5073 PP : constant Node_Id := 5074 Get_Pragma (Rec, Pragma_Pack); 5075 begin 5076 if Present (PP) then 5077 Error_Msg_Name_1 := CN; 5078 Error_Msg_Sloc := Sloc (Comp); 5079 Error_Msg_N 5080 ("pragma Pack affects convention % component#??", 5081 PP); 5082 Error_Msg_Name_1 := CN; 5083 Error_Msg_NE 5084 ("\component & may not have % compatible " 5085 & "representation??", PP, Comp); 5086 end if; 5087 end; 5088 end if; 5089 5090 -- Check for error of component clause given for variable 5091 -- sized type. We have to delay this test till this point, 5092 -- since the component type has to be frozen for us to know 5093 -- if it is variable length. 5094 5095 if Present (CC) then 5096 Placed_Component := True; 5097 5098 -- We omit this test in a generic context, it will be 5099 -- applied at instantiation time. 5100 5101 if Inside_A_Generic then 5102 null; 5103 5104 -- Also omit this test in CodePeer mode, since we do not 5105 -- have sufficient info on size and rep clauses. 5106 5107 elsif CodePeer_Mode then 5108 null; 5109 5110 -- Do the check 5111 5112 elsif not 5113 Size_Known_At_Compile_Time 5114 (Underlying_Type (Etype (Comp))) 5115 then 5116 Error_Msg_N 5117 ("component clause not allowed for variable " & 5118 "length component", CC); 5119 end if; 5120 5121 else 5122 Unplaced_Component := True; 5123 end if; 5124 5125 -- Case of component requires byte alignment 5126 5127 if Must_Be_On_Byte_Boundary (Etype (Comp)) then 5128 5129 -- Set the enclosing record to also require byte align 5130 5131 Set_Must_Be_On_Byte_Boundary (Rec); 5132 5133 -- Check for component clause that is inconsistent with 5134 -- the required byte boundary alignment. 5135 5136 if Present (CC) 5137 and then Normalized_First_Bit (Comp) mod 5138 System_Storage_Unit /= 0 5139 then 5140 Error_Msg_N 5141 ("component & must be byte aligned", 5142 Component_Name (Component_Clause (Comp))); 5143 end if; 5144 end if; 5145 end; 5146 end if; 5147 5148 -- Gather data for possible Implicit_Packing later. Note that at 5149 -- this stage we might be dealing with a real component, or with 5150 -- an implicit subtype declaration. 5151 5152 if Known_Static_RM_Size (Etype (Comp)) then 5153 declare 5154 Comp_Type : constant Entity_Id := Etype (Comp); 5155 Comp_Size : constant Uint := RM_Size (Comp_Type); 5156 SSU : constant Int := Ttypes.System_Storage_Unit; 5157 5158 begin 5159 Sized_Component_Total_RM_Size := 5160 Sized_Component_Total_RM_Size + Comp_Size; 5161 5162 Sized_Component_Total_Round_RM_Size := 5163 Sized_Component_Total_Round_RM_Size + 5164 (Comp_Size + SSU - 1) / SSU * SSU; 5165 5166 if Present (Underlying_Type (Comp_Type)) 5167 and then Is_Elementary_Type (Underlying_Type (Comp_Type)) 5168 then 5169 Elem_Component_Total_Esize := 5170 Elem_Component_Total_Esize + Esize (Comp_Type); 5171 else 5172 All_Elem_Components := False; 5173 5174 if Comp_Size mod SSU /= 0 then 5175 All_Storage_Unit_Components := False; 5176 end if; 5177 end if; 5178 end; 5179 else 5180 All_Sized_Components := False; 5181 end if; 5182 5183 -- If the component is an Itype with Delayed_Freeze and is either 5184 -- a record or array subtype and its base type has not yet been 5185 -- frozen, we must remove this from the entity list of this record 5186 -- and put it on the entity list of the scope of its base type. 5187 -- Note that we know that this is not the type of a component 5188 -- since we cleared Has_Delayed_Freeze for it in the previous 5189 -- loop. Thus this must be the Designated_Type of an access type, 5190 -- which is the type of a component. 5191 5192 if Is_Itype (Comp) 5193 and then Is_Type (Scope (Comp)) 5194 and then Is_Composite_Type (Comp) 5195 and then Base_Type (Comp) /= Comp 5196 and then Has_Delayed_Freeze (Comp) 5197 and then not Is_Frozen (Base_Type (Comp)) 5198 then 5199 declare 5200 Will_Be_Frozen : Boolean := False; 5201 S : Entity_Id; 5202 5203 begin 5204 -- We have a difficult case to handle here. Suppose Rec is 5205 -- subtype being defined in a subprogram that's created as 5206 -- part of the freezing of Rec'Base. In that case, we know 5207 -- that Comp'Base must have already been frozen by the time 5208 -- we get to elaborate this because Gigi doesn't elaborate 5209 -- any bodies until it has elaborated all of the declarative 5210 -- part. But Is_Frozen will not be set at this point because 5211 -- we are processing code in lexical order. 5212 5213 -- We detect this case by going up the Scope chain of Rec 5214 -- and seeing if we have a subprogram scope before reaching 5215 -- the top of the scope chain or that of Comp'Base. If we 5216 -- do, then mark that Comp'Base will actually be frozen. If 5217 -- so, we merely undelay it. 5218 5219 S := Scope (Rec); 5220 while Present (S) loop 5221 if Is_Subprogram (S) then 5222 Will_Be_Frozen := True; 5223 exit; 5224 elsif S = Scope (Base_Type (Comp)) then 5225 exit; 5226 end if; 5227 5228 S := Scope (S); 5229 end loop; 5230 5231 if Will_Be_Frozen then 5232 Undelay_Type (Comp); 5233 5234 else 5235 if Present (Prev) then 5236 Link_Entities (Prev, Next_Entity (Comp)); 5237 else 5238 Set_First_Entity (Rec, Next_Entity (Comp)); 5239 end if; 5240 5241 -- Insert in entity list of scope of base type (which 5242 -- must be an enclosing scope, because still unfrozen). 5243 5244 Append_Entity (Comp, Scope (Base_Type (Comp))); 5245 end if; 5246 end; 5247 5248 -- If the component is an access type with an allocator as default 5249 -- value, the designated type will be frozen by the corresponding 5250 -- expression in init_proc. In order to place the freeze node for 5251 -- the designated type before that for the current record type, 5252 -- freeze it now. 5253 5254 -- Same process if the component is an array of access types, 5255 -- initialized with an aggregate. If the designated type is 5256 -- private, it cannot contain allocators, and it is premature 5257 -- to freeze the type, so we check for this as well. 5258 5259 elsif Is_Access_Type (Etype (Comp)) 5260 and then Present (Parent (Comp)) 5261 and then 5262 Nkind (Parent (Comp)) 5263 in N_Component_Declaration | N_Discriminant_Specification 5264 and then Present (Expression (Parent (Comp))) 5265 then 5266 declare 5267 Alloc : constant Node_Id := 5268 Unqualify (Expression (Parent (Comp))); 5269 5270 begin 5271 if Nkind (Alloc) = N_Allocator then 5272 5273 -- If component is pointer to a class-wide type, freeze 5274 -- the specific type in the expression being allocated. 5275 -- The expression may be a subtype indication, in which 5276 -- case freeze the subtype mark. 5277 5278 if Is_Class_Wide_Type (Designated_Type (Etype (Comp))) 5279 then 5280 if Is_Entity_Name (Expression (Alloc)) then 5281 Freeze_And_Append 5282 (Entity (Expression (Alloc)), N, Result); 5283 5284 elsif Nkind (Expression (Alloc)) = N_Subtype_Indication 5285 then 5286 Freeze_And_Append 5287 (Entity (Subtype_Mark (Expression (Alloc))), 5288 N, Result); 5289 end if; 5290 elsif Is_Itype (Designated_Type (Etype (Comp))) then 5291 Check_Itype (Etype (Comp)); 5292 else 5293 Freeze_And_Append 5294 (Designated_Type (Etype (Comp)), N, Result); 5295 end if; 5296 end if; 5297 end; 5298 elsif Is_Access_Type (Etype (Comp)) 5299 and then Is_Itype (Designated_Type (Etype (Comp))) 5300 then 5301 Check_Itype (Etype (Comp)); 5302 5303 -- Freeze the designated type when initializing a component with 5304 -- an aggregate in case the aggregate contains allocators. 5305 5306 -- type T is ...; 5307 -- type T_Ptr is access all T; 5308 -- type T_Array is array ... of T_Ptr; 5309 5310 -- type Rec is record 5311 -- Comp : T_Array := (others => ...); 5312 -- end record; 5313 5314 elsif Is_Array_Type (Etype (Comp)) 5315 and then Is_Access_Type (Component_Type (Etype (Comp))) 5316 then 5317 declare 5318 Comp_Par : constant Node_Id := Parent (Comp); 5319 Desig_Typ : constant Entity_Id := 5320 Designated_Type 5321 (Component_Type (Etype (Comp))); 5322 5323 begin 5324 -- The only case when this sort of freezing is not done is 5325 -- when the designated type is class-wide and the root type 5326 -- is the record owning the component. This scenario results 5327 -- in a circularity because the class-wide type requires 5328 -- primitives that have not been created yet as the root 5329 -- type is in the process of being frozen. 5330 5331 -- type Rec is tagged; 5332 -- type Rec_Ptr is access all Rec'Class; 5333 -- type Rec_Array is array ... of Rec_Ptr; 5334 5335 -- type Rec is record 5336 -- Comp : Rec_Array := (others => ...); 5337 -- end record; 5338 5339 if Is_Class_Wide_Type (Desig_Typ) 5340 and then Root_Type (Desig_Typ) = Rec 5341 then 5342 null; 5343 5344 elsif Is_Fully_Defined (Desig_Typ) 5345 and then Present (Comp_Par) 5346 and then Nkind (Comp_Par) = N_Component_Declaration 5347 and then Present (Expression (Comp_Par)) 5348 and then Nkind (Expression (Comp_Par)) = N_Aggregate 5349 then 5350 Freeze_And_Append (Desig_Typ, N, Result); 5351 end if; 5352 end; 5353 end if; 5354 5355 Prev := Comp; 5356 Next_Entity (Comp); 5357 end loop; 5358 5359 SSO_ADC := 5360 Get_Attribute_Definition_Clause 5361 (Rec, Attribute_Scalar_Storage_Order); 5362 5363 -- If the record type has Complex_Representation, then it is treated 5364 -- as a scalar in the back end so the storage order is irrelevant. 5365 5366 if Has_Complex_Representation (Rec) then 5367 if Present (SSO_ADC) then 5368 Error_Msg_N 5369 ("??storage order has no effect with Complex_Representation", 5370 SSO_ADC); 5371 end if; 5372 5373 else 5374 -- Deal with default setting of reverse storage order 5375 5376 Set_SSO_From_Default (Rec); 5377 5378 -- Check consistent attribute setting on component types 5379 5380 declare 5381 Comp_ADC_Present : Boolean; 5382 begin 5383 Comp := First_Component (Rec); 5384 while Present (Comp) loop 5385 Check_Component_Storage_Order 5386 (Encl_Type => Rec, 5387 Comp => Comp, 5388 ADC => SSO_ADC, 5389 Comp_ADC_Present => Comp_ADC_Present); 5390 SSO_ADC_Component := SSO_ADC_Component or Comp_ADC_Present; 5391 Next_Component (Comp); 5392 end loop; 5393 end; 5394 5395 -- Now deal with reverse storage order/bit order issues 5396 5397 if Present (SSO_ADC) then 5398 5399 -- Check compatibility of Scalar_Storage_Order with Bit_Order, 5400 -- if the former is specified. 5401 5402 if Reverse_Bit_Order (Rec) /= Reverse_Storage_Order (Rec) then 5403 5404 -- Note: report error on Rec, not on SSO_ADC, as ADC may 5405 -- apply to some ancestor type. 5406 5407 Error_Msg_Sloc := Sloc (SSO_ADC); 5408 Error_Msg_N 5409 ("scalar storage order for& specified# inconsistent with " 5410 & "bit order", Rec); 5411 end if; 5412 5413 -- Warn if there is a Scalar_Storage_Order attribute definition 5414 -- clause but no component clause, no component that itself has 5415 -- such an attribute definition, and no pragma Pack. 5416 5417 if not (Placed_Component 5418 or else 5419 SSO_ADC_Component 5420 or else 5421 Is_Packed (Rec)) 5422 then 5423 Error_Msg_N 5424 ("??scalar storage order specified but no component " 5425 & "clause", SSO_ADC); 5426 end if; 5427 end if; 5428 end if; 5429 5430 -- Deal with Bit_Order aspect 5431 5432 ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order); 5433 5434 if Present (ADC) and then Base_Type (Rec) = Rec then 5435 if not (Placed_Component 5436 or else Present (SSO_ADC) 5437 or else Is_Packed (Rec)) 5438 then 5439 -- Warn if clause has no effect when no component clause is 5440 -- present, but suppress warning if the Bit_Order is required 5441 -- due to the presence of a Scalar_Storage_Order attribute. 5442 5443 Error_Msg_N 5444 ("??bit order specification has no effect", ADC); 5445 Error_Msg_N 5446 ("\??since no component clauses were specified", ADC); 5447 5448 -- Here is where we do the processing to adjust component clauses 5449 -- for reversed bit order, when not using reverse SSO. If an error 5450 -- has been reported on Rec already (such as SSO incompatible with 5451 -- bit order), don't bother adjusting as this may generate extra 5452 -- noise. 5453 5454 elsif Reverse_Bit_Order (Rec) 5455 and then not Reverse_Storage_Order (Rec) 5456 and then not Error_Posted (Rec) 5457 then 5458 Adjust_Record_For_Reverse_Bit_Order (Rec); 5459 5460 -- Case where we have both an explicit Bit_Order and the same 5461 -- Scalar_Storage_Order: leave record untouched, the back-end 5462 -- will take care of required layout conversions. 5463 5464 else 5465 null; 5466 5467 end if; 5468 end if; 5469 5470 -- Check for useless pragma Pack when all components placed. We only 5471 -- do this check for record types, not subtypes, since a subtype may 5472 -- have all its components placed, and it still makes perfectly good 5473 -- sense to pack other subtypes or the parent type. We do not give 5474 -- this warning if Optimize_Alignment is set to Space, since the 5475 -- pragma Pack does have an effect in this case (it always resets 5476 -- the alignment to one). 5477 5478 if Ekind (Rec) = E_Record_Type 5479 and then Is_Packed (Rec) 5480 and then not Unplaced_Component 5481 and then Optimize_Alignment /= 'S' 5482 then 5483 -- Reset packed status. Probably not necessary, but we do it so 5484 -- that there is no chance of the back end doing something strange 5485 -- with this redundant indication of packing. 5486 5487 Set_Is_Packed (Rec, False); 5488 5489 -- Give warning if redundant constructs warnings on 5490 5491 if Warn_On_Redundant_Constructs then 5492 Error_Msg_N -- CODEFIX 5493 ("??pragma Pack has no effect, no unplaced components", 5494 Get_Rep_Pragma (Rec, Name_Pack)); 5495 end if; 5496 end if; 5497 5498 -- If this is the record corresponding to a remote type, freeze the 5499 -- remote type here since that is what we are semantically freezing. 5500 -- This prevents the freeze node for that type in an inner scope. 5501 5502 if Ekind (Rec) = E_Record_Type then 5503 if Present (Corresponding_Remote_Type (Rec)) then 5504 Freeze_And_Append (Corresponding_Remote_Type (Rec), N, Result); 5505 end if; 5506 5507 -- Check for controlled components, unchecked unions, and type 5508 -- invariants. 5509 5510 Comp := First_Component (Rec); 5511 while Present (Comp) loop 5512 5513 -- Do not set Has_Controlled_Component on a class-wide 5514 -- equivalent type. See Make_CW_Equivalent_Type. 5515 5516 if not Is_Class_Wide_Equivalent_Type (Rec) 5517 and then 5518 (Has_Controlled_Component (Etype (Comp)) 5519 or else 5520 (Chars (Comp) /= Name_uParent 5521 and then Is_Controlled (Etype (Comp))) 5522 or else 5523 (Is_Protected_Type (Etype (Comp)) 5524 and then 5525 Present (Corresponding_Record_Type (Etype (Comp))) 5526 and then 5527 Has_Controlled_Component 5528 (Corresponding_Record_Type (Etype (Comp))))) 5529 then 5530 Set_Has_Controlled_Component (Rec); 5531 end if; 5532 5533 if Has_Unchecked_Union (Etype (Comp)) then 5534 Set_Has_Unchecked_Union (Rec); 5535 end if; 5536 5537 -- The record type requires its own invariant procedure in 5538 -- order to verify the invariant of each individual component. 5539 -- Do not consider internal components such as _parent because 5540 -- parent class-wide invariants are always inherited. 5541 -- In GNATprove mode, the component invariants are checked by 5542 -- other means. They should not be added to the record type 5543 -- invariant procedure, so that the procedure can be used to 5544 -- check the recordy type invariants if any. 5545 5546 if Comes_From_Source (Comp) 5547 and then Has_Invariants (Etype (Comp)) 5548 and then not GNATprove_Mode 5549 then 5550 Set_Has_Own_Invariants (Rec); 5551 end if; 5552 5553 -- Scan component declaration for likely misuses of current 5554 -- instance, either in a constraint or a default expression. 5555 5556 if Has_Per_Object_Constraint (Comp) then 5557 Check_Current_Instance (Parent (Comp)); 5558 end if; 5559 5560 Next_Component (Comp); 5561 end loop; 5562 end if; 5563 5564 -- Enforce the restriction that access attributes with a current 5565 -- instance prefix can only apply to limited types. This comment 5566 -- is floating here, but does not seem to belong here??? 5567 5568 -- Set component alignment if not otherwise already set 5569 5570 Set_Component_Alignment_If_Not_Set (Rec); 5571 5572 -- For first subtypes, check if there are any fixed-point fields with 5573 -- component clauses, where we must check the size. This is not done 5574 -- till the freeze point since for fixed-point types, we do not know 5575 -- the size until the type is frozen. Similar processing applies to 5576 -- bit-packed arrays. 5577 5578 if Is_First_Subtype (Rec) then 5579 Comp := First_Component (Rec); 5580 while Present (Comp) loop 5581 if Present (Component_Clause (Comp)) 5582 and then (Is_Fixed_Point_Type (Etype (Comp)) 5583 or else Is_Bit_Packed_Array (Etype (Comp))) 5584 then 5585 Check_Size 5586 (Component_Name (Component_Clause (Comp)), 5587 Etype (Comp), 5588 Esize (Comp), 5589 Junk); 5590 end if; 5591 5592 Next_Component (Comp); 5593 end loop; 5594 end if; 5595 5596 -- See if Size is too small as is (and implicit packing might help) 5597 5598 if not Is_Packed (Rec) 5599 5600 -- No implicit packing if even one component is explicitly placed 5601 5602 and then not Placed_Component 5603 5604 -- Or even one component is aliased 5605 5606 and then not Aliased_Component 5607 5608 -- Must have size clause and all sized components 5609 5610 and then Has_Size_Clause (Rec) 5611 and then All_Sized_Components 5612 5613 -- Do not try implicit packing on records with discriminants, too 5614 -- complicated, especially in the variant record case. 5615 5616 and then not Has_Discriminants (Rec) 5617 5618 -- We want to implicitly pack if the specified size of the record 5619 -- is less than the sum of the object sizes (no point in packing 5620 -- if this is not the case), if we can compute it, i.e. if we have 5621 -- only elementary components. Otherwise, we have at least one 5622 -- composite component and we want to implicitly pack only if bit 5623 -- packing is required for it, as we are sure in this case that 5624 -- the back end cannot do the expected layout without packing. 5625 5626 and then 5627 ((All_Elem_Components 5628 and then RM_Size (Rec) < Elem_Component_Total_Esize) 5629 or else 5630 (not All_Elem_Components 5631 and then not All_Storage_Unit_Components 5632 and then RM_Size (Rec) < Sized_Component_Total_Round_RM_Size)) 5633 5634 -- And the total RM size cannot be greater than the specified size 5635 -- since otherwise packing will not get us where we have to be. 5636 5637 and then Sized_Component_Total_RM_Size <= RM_Size (Rec) 5638 5639 -- Never do implicit packing in CodePeer or SPARK modes since 5640 -- we don't do any packing in these modes, since this generates 5641 -- over-complex code that confuses static analysis, and in 5642 -- general, neither CodePeer not GNATprove care about the 5643 -- internal representation of objects. 5644 5645 and then not (CodePeer_Mode or GNATprove_Mode) 5646 then 5647 -- If implicit packing enabled, do it 5648 5649 if Implicit_Packing then 5650 Set_Is_Packed (Rec); 5651 5652 -- Otherwise flag the size clause 5653 5654 else 5655 declare 5656 Sz : constant Node_Id := Size_Clause (Rec); 5657 begin 5658 Error_Msg_NE -- CODEFIX 5659 ("size given for& too small", Sz, Rec); 5660 Error_Msg_N -- CODEFIX 5661 ("\use explicit pragma Pack " 5662 & "or use pragma Implicit_Packing", Sz); 5663 end; 5664 end if; 5665 end if; 5666 5667 -- The following checks are relevant only when SPARK_Mode is on as 5668 -- they are not standard Ada legality rules. 5669 5670 if SPARK_Mode = On then 5671 5672 -- A discriminated type cannot be effectively volatile 5673 -- (SPARK RM 7.1.3(5)). 5674 5675 if Is_Effectively_Volatile (Rec) then 5676 if Has_Discriminants (Rec) then 5677 Error_Msg_N ("discriminated type & cannot be volatile", Rec); 5678 end if; 5679 5680 -- A non-effectively volatile record type cannot contain 5681 -- effectively volatile components (SPARK RM 7.1.3(6)). 5682 5683 else 5684 Comp := First_Component (Rec); 5685 while Present (Comp) loop 5686 if Comes_From_Source (Comp) 5687 and then Is_Effectively_Volatile (Etype (Comp)) 5688 then 5689 Error_Msg_Name_1 := Chars (Rec); 5690 Error_Msg_N 5691 ("component & of non-volatile type % cannot be " 5692 & "volatile", Comp); 5693 end if; 5694 5695 Next_Component (Comp); 5696 end loop; 5697 end if; 5698 5699 -- A type which does not yield a synchronized object cannot have 5700 -- a component that yields a synchronized object (SPARK RM 9.5). 5701 5702 if not Yields_Synchronized_Object (Rec) then 5703 Comp := First_Component (Rec); 5704 while Present (Comp) loop 5705 if Comes_From_Source (Comp) 5706 and then Yields_Synchronized_Object (Etype (Comp)) 5707 then 5708 Error_Msg_Name_1 := Chars (Rec); 5709 Error_Msg_N 5710 ("component & of non-synchronized type % cannot be " 5711 & "synchronized", Comp); 5712 end if; 5713 5714 Next_Component (Comp); 5715 end loop; 5716 end if; 5717 5718 -- A Ghost type cannot have a component of protected or task type 5719 -- (SPARK RM 6.9(19)). 5720 5721 if Is_Ghost_Entity (Rec) then 5722 Comp := First_Component (Rec); 5723 while Present (Comp) loop 5724 if Comes_From_Source (Comp) 5725 and then Is_Concurrent_Type (Etype (Comp)) 5726 then 5727 Error_Msg_Name_1 := Chars (Rec); 5728 Error_Msg_N 5729 ("component & of ghost type % cannot be concurrent", 5730 Comp); 5731 end if; 5732 5733 Next_Component (Comp); 5734 end loop; 5735 end if; 5736 end if; 5737 5738 -- Make sure that if we have an iterator aspect, then we have 5739 -- either Constant_Indexing or Variable_Indexing. 5740 5741 declare 5742 Iterator_Aspect : Node_Id; 5743 5744 begin 5745 Iterator_Aspect := Find_Aspect (Rec, Aspect_Iterator_Element); 5746 5747 if No (Iterator_Aspect) then 5748 Iterator_Aspect := Find_Aspect (Rec, Aspect_Default_Iterator); 5749 end if; 5750 5751 if Present (Iterator_Aspect) then 5752 if Has_Aspect (Rec, Aspect_Constant_Indexing) 5753 or else 5754 Has_Aspect (Rec, Aspect_Variable_Indexing) 5755 then 5756 null; 5757 else 5758 Error_Msg_N 5759 ("Iterator_Element requires indexing aspect", 5760 Iterator_Aspect); 5761 end if; 5762 end if; 5763 end; 5764 5765 -- All done if not a full record definition 5766 5767 if Ekind (Rec) /= E_Record_Type then 5768 return; 5769 end if; 5770 5771 -- Finally we need to check the variant part to make sure that 5772 -- all types within choices are properly frozen as part of the 5773 -- freezing of the record type. 5774 5775 Check_Variant_Part : declare 5776 D : constant Node_Id := Declaration_Node (Rec); 5777 T : Node_Id; 5778 C : Node_Id; 5779 5780 begin 5781 -- Find component list 5782 5783 C := Empty; 5784 5785 if Nkind (D) = N_Full_Type_Declaration then 5786 T := Type_Definition (D); 5787 5788 if Nkind (T) = N_Record_Definition then 5789 C := Component_List (T); 5790 5791 elsif Nkind (T) = N_Derived_Type_Definition 5792 and then Present (Record_Extension_Part (T)) 5793 then 5794 C := Component_List (Record_Extension_Part (T)); 5795 end if; 5796 end if; 5797 5798 -- Case of variant part present 5799 5800 if Present (C) and then Present (Variant_Part (C)) then 5801 Freeze_Choices_In_Variant_Part (Variant_Part (C)); 5802 end if; 5803 5804 -- Note: we used to call Check_Choices here, but it is too early, 5805 -- since predicated subtypes are frozen here, but their freezing 5806 -- actions are in Analyze_Freeze_Entity, which has not been called 5807 -- yet for entities frozen within this procedure, so we moved that 5808 -- call to the Analyze_Freeze_Entity for the record type. 5809 5810 end Check_Variant_Part; 5811 5812 -- Check that all the primitives of an interface type are abstract 5813 -- or null procedures. 5814 5815 if Is_Interface (Rec) 5816 and then not Error_Posted (Parent (Rec)) 5817 then 5818 declare 5819 Elmt : Elmt_Id; 5820 Subp : Entity_Id; 5821 5822 begin 5823 Elmt := First_Elmt (Primitive_Operations (Rec)); 5824 while Present (Elmt) loop 5825 Subp := Node (Elmt); 5826 5827 if not Is_Abstract_Subprogram (Subp) 5828 5829 -- Avoid reporting the error on inherited primitives 5830 5831 and then Comes_From_Source (Subp) 5832 then 5833 Error_Msg_Name_1 := Chars (Subp); 5834 5835 if Ekind (Subp) = E_Procedure then 5836 if not Null_Present (Parent (Subp)) then 5837 Error_Msg_N 5838 ("interface procedure % must be abstract or null", 5839 Parent (Subp)); 5840 end if; 5841 else 5842 Error_Msg_N 5843 ("interface function % must be abstract", 5844 Parent (Subp)); 5845 end if; 5846 end if; 5847 5848 Next_Elmt (Elmt); 5849 end loop; 5850 end; 5851 end if; 5852 5853 -- For a derived tagged type, check whether inherited primitives 5854 -- might require a wrapper to handle class-wide conditions. 5855 5856 if Is_Tagged_Type (Rec) and then Is_Derived_Type (Rec) then 5857 Check_Inherited_Conditions (Rec); 5858 end if; 5859 end Freeze_Record_Type; 5860 5861 ------------------------------- 5862 -- Has_Boolean_Aspect_Import -- 5863 ------------------------------- 5864 5865 function Has_Boolean_Aspect_Import (E : Entity_Id) return Boolean is 5866 Decl : constant Node_Id := Declaration_Node (E); 5867 Asp : Node_Id; 5868 Expr : Node_Id; 5869 5870 begin 5871 if Has_Aspects (Decl) then 5872 Asp := First (Aspect_Specifications (Decl)); 5873 while Present (Asp) loop 5874 Expr := Expression (Asp); 5875 5876 -- The value of aspect Import is True when the expression is 5877 -- either missing or it is explicitly set to True. 5878 5879 if Get_Aspect_Id (Asp) = Aspect_Import 5880 and then (No (Expr) 5881 or else (Compile_Time_Known_Value (Expr) 5882 and then Is_True (Expr_Value (Expr)))) 5883 then 5884 return True; 5885 end if; 5886 5887 Next (Asp); 5888 end loop; 5889 end if; 5890 5891 return False; 5892 end Has_Boolean_Aspect_Import; 5893 5894 ------------------------- 5895 -- Inherit_Freeze_Node -- 5896 ------------------------- 5897 5898 procedure Inherit_Freeze_Node 5899 (Fnod : Node_Id; 5900 Typ : Entity_Id) 5901 is 5902 Typ_Fnod : constant Node_Id := Freeze_Node (Typ); 5903 5904 begin 5905 Set_Freeze_Node (Typ, Fnod); 5906 Set_Entity (Fnod, Typ); 5907 5908 -- The input type had an existing node. Propagate relevant attributes 5909 -- from the old freeze node to the inherited freeze node. 5910 5911 -- ??? if both freeze nodes have attributes, would they differ? 5912 5913 if Present (Typ_Fnod) then 5914 5915 -- Attribute Access_Types_To_Process 5916 5917 if Present (Access_Types_To_Process (Typ_Fnod)) 5918 and then No (Access_Types_To_Process (Fnod)) 5919 then 5920 Set_Access_Types_To_Process (Fnod, 5921 Access_Types_To_Process (Typ_Fnod)); 5922 end if; 5923 5924 -- Attribute Actions 5925 5926 if Present (Actions (Typ_Fnod)) and then No (Actions (Fnod)) then 5927 Set_Actions (Fnod, Actions (Typ_Fnod)); 5928 end if; 5929 5930 -- Attribute First_Subtype_Link 5931 5932 if Present (First_Subtype_Link (Typ_Fnod)) 5933 and then No (First_Subtype_Link (Fnod)) 5934 then 5935 Set_First_Subtype_Link (Fnod, First_Subtype_Link (Typ_Fnod)); 5936 end if; 5937 5938 -- Attribute TSS_Elist 5939 5940 if Present (TSS_Elist (Typ_Fnod)) 5941 and then No (TSS_Elist (Fnod)) 5942 then 5943 Set_TSS_Elist (Fnod, TSS_Elist (Typ_Fnod)); 5944 end if; 5945 end if; 5946 end Inherit_Freeze_Node; 5947 5948 ------------------------------ 5949 -- Wrap_Imported_Subprogram -- 5950 ------------------------------ 5951 5952 -- The issue here is that our normal approach of checking preconditions 5953 -- and postconditions does not work for imported procedures, since we 5954 -- are not generating code for the body. To get around this we create 5955 -- a wrapper, as shown by the following example: 5956 5957 -- procedure K (A : Integer); 5958 -- pragma Import (C, K); 5959 5960 -- The spec is rewritten by removing the effects of pragma Import, but 5961 -- leaving the convention unchanged, as though the source had said: 5962 5963 -- procedure K (A : Integer); 5964 -- pragma Convention (C, K); 5965 5966 -- and we create a body, added to the entity K freeze actions, which 5967 -- looks like: 5968 5969 -- procedure K (A : Integer) is 5970 -- procedure K (A : Integer); 5971 -- pragma Import (C, K); 5972 -- begin 5973 -- K (A); 5974 -- end K; 5975 5976 -- Now the contract applies in the normal way to the outer procedure, 5977 -- and the inner procedure has no contracts, so there is no problem 5978 -- in just calling it to get the original effect. 5979 5980 -- In the case of a function, we create an appropriate return statement 5981 -- for the subprogram body that calls the inner procedure. 5982 5983 procedure Wrap_Imported_Subprogram (E : Entity_Id) is 5984 function Copy_Import_Pragma return Node_Id; 5985 -- Obtain a copy of the Import_Pragma which belongs to subprogram E 5986 5987 ------------------------ 5988 -- Copy_Import_Pragma -- 5989 ------------------------ 5990 5991 function Copy_Import_Pragma return Node_Id is 5992 5993 -- The subprogram should have an import pragma, otherwise it does 5994 -- need a wrapper. 5995 5996 Prag : constant Node_Id := Import_Pragma (E); 5997 pragma Assert (Present (Prag)); 5998 5999 -- Save all semantic fields of the pragma 6000 6001 Save_Asp : constant Node_Id := Corresponding_Aspect (Prag); 6002 Save_From : constant Boolean := From_Aspect_Specification (Prag); 6003 Save_Prag : constant Node_Id := Next_Pragma (Prag); 6004 Save_Rep : constant Node_Id := Next_Rep_Item (Prag); 6005 6006 Result : Node_Id; 6007 6008 begin 6009 -- Reset all semantic fields. This avoids a potential infinite 6010 -- loop when the pragma comes from an aspect as the duplication 6011 -- will copy the aspect, then copy the corresponding pragma and 6012 -- so on. 6013 6014 Set_Corresponding_Aspect (Prag, Empty); 6015 Set_From_Aspect_Specification (Prag, False); 6016 Set_Next_Pragma (Prag, Empty); 6017 Set_Next_Rep_Item (Prag, Empty); 6018 6019 Result := Copy_Separate_Tree (Prag); 6020 6021 -- Restore the original semantic fields 6022 6023 Set_Corresponding_Aspect (Prag, Save_Asp); 6024 Set_From_Aspect_Specification (Prag, Save_From); 6025 Set_Next_Pragma (Prag, Save_Prag); 6026 Set_Next_Rep_Item (Prag, Save_Rep); 6027 6028 return Result; 6029 end Copy_Import_Pragma; 6030 6031 -- Local variables 6032 6033 Loc : constant Source_Ptr := Sloc (E); 6034 CE : constant Name_Id := Chars (E); 6035 Bod : Node_Id; 6036 Forml : Entity_Id; 6037 Parms : List_Id; 6038 Prag : Node_Id; 6039 Spec : Node_Id; 6040 Stmt : Node_Id; 6041 6042 -- Start of processing for Wrap_Imported_Subprogram 6043 6044 begin 6045 -- Nothing to do if not imported 6046 6047 if not Is_Imported (E) then 6048 return; 6049 6050 -- Test enabling conditions for wrapping 6051 6052 elsif Is_Subprogram (E) 6053 and then Present (Contract (E)) 6054 and then Present (Pre_Post_Conditions (Contract (E))) 6055 and then not GNATprove_Mode 6056 then 6057 -- Here we do the wrap 6058 6059 -- Note on calls to Copy_Separate_Tree. The trees we are copying 6060 -- here are fully analyzed, but we definitely want fully syntactic 6061 -- unanalyzed trees in the body we construct, so that the analysis 6062 -- generates the right visibility, and that is exactly what the 6063 -- calls to Copy_Separate_Tree give us. 6064 6065 Prag := Copy_Import_Pragma; 6066 6067 -- Fix up spec so it is no longer imported and has convention Ada 6068 6069 Set_Has_Completion (E, False); 6070 Set_Import_Pragma (E, Empty); 6071 Set_Interface_Name (E, Empty); 6072 Set_Is_Imported (E, False); 6073 Set_Convention (E, Convention_Ada); 6074 6075 -- Grab the subprogram declaration and specification 6076 6077 Spec := Declaration_Node (E); 6078 6079 -- Build parameter list that we need 6080 6081 Parms := New_List; 6082 Forml := First_Formal (E); 6083 while Present (Forml) loop 6084 Append_To (Parms, Make_Identifier (Loc, Chars (Forml))); 6085 Next_Formal (Forml); 6086 end loop; 6087 6088 -- Build the call 6089 6090 -- An imported function whose result type is anonymous access 6091 -- creates a new anonymous access type when it is relocated into 6092 -- the declarations of the body generated below. As a result, the 6093 -- accessibility level of these two anonymous access types may not 6094 -- be compatible even though they are essentially the same type. 6095 -- Use an unchecked type conversion to reconcile this case. Note 6096 -- that the conversion is safe because in the named access type 6097 -- case, both the body and imported function utilize the same 6098 -- type. 6099 6100 if Ekind (E) in E_Function | E_Generic_Function then 6101 Stmt := 6102 Make_Simple_Return_Statement (Loc, 6103 Expression => 6104 Unchecked_Convert_To (Etype (E), 6105 Make_Function_Call (Loc, 6106 Name => Make_Identifier (Loc, CE), 6107 Parameter_Associations => Parms))); 6108 6109 else 6110 Stmt := 6111 Make_Procedure_Call_Statement (Loc, 6112 Name => Make_Identifier (Loc, CE), 6113 Parameter_Associations => Parms); 6114 end if; 6115 6116 -- Now build the body 6117 6118 Bod := 6119 Make_Subprogram_Body (Loc, 6120 Specification => 6121 Copy_Separate_Tree (Spec), 6122 Declarations => New_List ( 6123 Make_Subprogram_Declaration (Loc, 6124 Specification => Copy_Separate_Tree (Spec)), 6125 Prag), 6126 Handled_Statement_Sequence => 6127 Make_Handled_Sequence_Of_Statements (Loc, 6128 Statements => New_List (Stmt), 6129 End_Label => Make_Identifier (Loc, CE))); 6130 6131 -- Append the body to freeze result 6132 6133 Add_To_Result (Bod); 6134 return; 6135 6136 -- Case of imported subprogram that does not get wrapped 6137 6138 else 6139 -- Set Is_Public. All imported entities need an external symbol 6140 -- created for them since they are always referenced from another 6141 -- object file. Note this used to be set when we set Is_Imported 6142 -- back in Sem_Prag, but now we delay it to this point, since we 6143 -- don't want to set this flag if we wrap an imported subprogram. 6144 6145 Set_Is_Public (E); 6146 end if; 6147 end Wrap_Imported_Subprogram; 6148 6149 -- Start of processing for Freeze_Entity 6150 6151 begin 6152 -- The entity being frozen may be subject to pragma Ghost. Set the mode 6153 -- now to ensure that any nodes generated during freezing are properly 6154 -- flagged as Ghost. 6155 6156 Set_Ghost_Mode (E); 6157 6158 -- We are going to test for various reasons why this entity need not be 6159 -- frozen here, but in the case of an Itype that's defined within a 6160 -- record, that test actually applies to the record. 6161 6162 if Is_Itype (E) and then Is_Record_Type (Scope (E)) then 6163 Test_E := Scope (E); 6164 6165 elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E))) 6166 and then Is_Record_Type (Underlying_Type (Scope (E))) 6167 then 6168 Test_E := Underlying_Type (Scope (E)); 6169 end if; 6170 6171 -- Do not freeze if already frozen since we only need one freeze node 6172 6173 if Is_Frozen (E) then 6174 Result := No_List; 6175 goto Leave; 6176 6177 -- Do not freeze if we are preanalyzing without freezing 6178 6179 elsif Inside_Preanalysis_Without_Freezing > 0 then 6180 Result := No_List; 6181 goto Leave; 6182 6183 elsif Ekind (E) = E_Generic_Package then 6184 Result := Freeze_Generic_Entities (E); 6185 goto Leave; 6186 6187 -- It is improper to freeze an external entity within a generic because 6188 -- its freeze node will appear in a non-valid context. The entity will 6189 -- be frozen in the proper scope after the current generic is analyzed. 6190 -- However, aspects must be analyzed because they may be queried later 6191 -- within the generic itself, and the corresponding pragma or attribute 6192 -- definition has not been analyzed yet. After this, indicate that the 6193 -- entity has no further delayed aspects, to prevent a later aspect 6194 -- analysis out of the scope of the generic. 6195 6196 elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then 6197 if Has_Delayed_Aspects (E) then 6198 Analyze_Aspects_At_Freeze_Point (E); 6199 Set_Has_Delayed_Aspects (E, False); 6200 end if; 6201 6202 Result := No_List; 6203 goto Leave; 6204 6205 -- AI05-0213: A formal incomplete type does not freeze the actual. In 6206 -- the instance, the same applies to the subtype renaming the actual. 6207 6208 elsif Is_Private_Type (E) 6209 and then Is_Generic_Actual_Type (E) 6210 and then No (Full_View (Base_Type (E))) 6211 and then Ada_Version >= Ada_2012 6212 then 6213 Result := No_List; 6214 goto Leave; 6215 6216 -- Formal subprograms are never frozen 6217 6218 elsif Is_Formal_Subprogram (E) then 6219 Result := No_List; 6220 goto Leave; 6221 6222 -- Generic types are never frozen as they lack delayed semantic checks 6223 6224 elsif Is_Generic_Type (E) then 6225 Result := No_List; 6226 goto Leave; 6227 6228 -- Do not freeze a global entity within an inner scope created during 6229 -- expansion. A call to subprogram E within some internal procedure 6230 -- (a stream attribute for example) might require freezing E, but the 6231 -- freeze node must appear in the same declarative part as E itself. 6232 -- The two-pass elaboration mechanism in gigi guarantees that E will 6233 -- be frozen before the inner call is elaborated. We exclude constants 6234 -- from this test, because deferred constants may be frozen early, and 6235 -- must be diagnosed (e.g. in the case of a deferred constant being used 6236 -- in a default expression). If the enclosing subprogram comes from 6237 -- source, or is a generic instance, then the freeze point is the one 6238 -- mandated by the language, and we freeze the entity. A subprogram that 6239 -- is a child unit body that acts as a spec does not have a spec that 6240 -- comes from source, but can only come from source. 6241 6242 elsif In_Open_Scopes (Scope (Test_E)) 6243 and then Scope (Test_E) /= Current_Scope 6244 and then Ekind (Test_E) /= E_Constant 6245 then 6246 declare 6247 S : Entity_Id; 6248 6249 begin 6250 S := Current_Scope; 6251 while Present (S) loop 6252 if Is_Overloadable (S) then 6253 if Comes_From_Source (S) 6254 or else Is_Generic_Instance (S) 6255 or else Is_Child_Unit (S) 6256 then 6257 exit; 6258 else 6259 Result := No_List; 6260 goto Leave; 6261 end if; 6262 end if; 6263 6264 S := Scope (S); 6265 end loop; 6266 end; 6267 6268 -- Similarly, an inlined instance body may make reference to global 6269 -- entities, but these references cannot be the proper freezing point 6270 -- for them, and in the absence of inlining freezing will take place in 6271 -- their own scope. Normally instance bodies are analyzed after the 6272 -- enclosing compilation, and everything has been frozen at the proper 6273 -- place, but with front-end inlining an instance body is compiled 6274 -- before the end of the enclosing scope, and as a result out-of-order 6275 -- freezing must be prevented. 6276 6277 elsif Front_End_Inlining 6278 and then In_Instance_Body 6279 and then Present (Scope (Test_E)) 6280 then 6281 declare 6282 S : Entity_Id; 6283 6284 begin 6285 S := Scope (Test_E); 6286 while Present (S) loop 6287 if Is_Generic_Instance (S) then 6288 exit; 6289 else 6290 S := Scope (S); 6291 end if; 6292 end loop; 6293 6294 if No (S) then 6295 Result := No_List; 6296 goto Leave; 6297 end if; 6298 end; 6299 end if; 6300 6301 -- Add checks to detect proper initialization of scalars that may appear 6302 -- as subprogram parameters. 6303 6304 if Is_Subprogram (E) and then Check_Validity_Of_Parameters then 6305 Apply_Parameter_Validity_Checks (E); 6306 end if; 6307 6308 -- Deal with delayed aspect specifications. The analysis of the aspect 6309 -- is required to be delayed to the freeze point, thus we analyze the 6310 -- pragma or attribute definition clause in the tree at this point. We 6311 -- also analyze the aspect specification node at the freeze point when 6312 -- the aspect doesn't correspond to pragma/attribute definition clause. 6313 -- In addition, a derived type may have inherited aspects that were 6314 -- delayed in the parent, so these must also be captured now. 6315 6316 -- For a record type, we deal with the delayed aspect specifications on 6317 -- components first, which is consistent with the non-delayed case and 6318 -- makes it possible to have a single processing to detect conflicts. 6319 6320 if Is_Record_Type (E) then 6321 declare 6322 Comp : Entity_Id; 6323 6324 Rec_Pushed : Boolean := False; 6325 -- Set True if the record type E has been pushed on the scope 6326 -- stack. Needed for the analysis of delayed aspects specified 6327 -- to the components of Rec. 6328 6329 begin 6330 Comp := First_Component (E); 6331 while Present (Comp) loop 6332 if Has_Delayed_Aspects (Comp) then 6333 if not Rec_Pushed then 6334 Push_Scope (E); 6335 Rec_Pushed := True; 6336 6337 -- The visibility to the discriminants must be restored 6338 -- in order to properly analyze the aspects. 6339 6340 if Has_Discriminants (E) then 6341 Install_Discriminants (E); 6342 end if; 6343 end if; 6344 6345 Analyze_Aspects_At_Freeze_Point (Comp); 6346 end if; 6347 6348 Next_Component (Comp); 6349 end loop; 6350 6351 -- Pop the scope if Rec scope has been pushed on the scope stack 6352 -- during the delayed aspect analysis process. 6353 6354 if Rec_Pushed then 6355 if Has_Discriminants (E) then 6356 Uninstall_Discriminants (E); 6357 end if; 6358 6359 Pop_Scope; 6360 end if; 6361 end; 6362 end if; 6363 6364 if Has_Delayed_Aspects (E) 6365 or else May_Inherit_Delayed_Rep_Aspects (E) 6366 then 6367 Analyze_Aspects_At_Freeze_Point (E); 6368 end if; 6369 6370 -- Here to freeze the entity 6371 6372 Set_Is_Frozen (E); 6373 6374 -- Case of entity being frozen is other than a type 6375 6376 if not Is_Type (E) then 6377 6378 -- If entity is exported or imported and does not have an external 6379 -- name, now is the time to provide the appropriate default name. 6380 -- Skip this if the entity is stubbed, since we don't need a name 6381 -- for any stubbed routine. For the case on intrinsics, if no 6382 -- external name is specified, then calls will be handled in 6383 -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an 6384 -- external name is provided, then Expand_Intrinsic_Call leaves 6385 -- calls in place for expansion by GIGI. 6386 6387 if (Is_Imported (E) or else Is_Exported (E)) 6388 and then No (Interface_Name (E)) 6389 and then Convention (E) /= Convention_Stubbed 6390 and then Convention (E) /= Convention_Intrinsic 6391 then 6392 Set_Encoded_Interface_Name 6393 (E, Get_Default_External_Name (E)); 6394 6395 -- If entity is an atomic object appearing in a declaration and 6396 -- the expression is an aggregate, assign it to a temporary to 6397 -- ensure that the actual assignment is done atomically rather 6398 -- than component-wise (the assignment to the temp may be done 6399 -- component-wise, but that is harmless). 6400 6401 elsif Is_Full_Access (E) 6402 and then Nkind (Parent (E)) = N_Object_Declaration 6403 and then Present (Expression (Parent (E))) 6404 and then Nkind (Expression (Parent (E))) = N_Aggregate 6405 and then Is_Full_Access_Aggregate (Expression (Parent (E))) 6406 then 6407 null; 6408 end if; 6409 6410 -- Subprogram case 6411 6412 if Is_Subprogram (E) then 6413 6414 -- Check for needing to wrap imported subprogram 6415 6416 Wrap_Imported_Subprogram (E); 6417 6418 -- Freeze all parameter types and the return type (RM 13.14(14)). 6419 -- However skip this for internal subprograms. This is also where 6420 -- any extra formal parameters are created since we now know 6421 -- whether the subprogram will use a foreign convention. 6422 6423 -- In Ada 2012, freezing a subprogram does not always freeze the 6424 -- corresponding profile (see AI05-019). An attribute reference 6425 -- is not a freezing point of the profile. Flag Do_Freeze_Profile 6426 -- indicates whether the profile should be frozen now. 6427 -- Other constructs that should not freeze ??? 6428 6429 -- This processing doesn't apply to internal entities (see below) 6430 6431 if not Is_Internal (E) and then Do_Freeze_Profile then 6432 if not Freeze_Profile (E) then 6433 goto Leave; 6434 end if; 6435 end if; 6436 6437 -- Must freeze its parent first if it is a derived subprogram 6438 6439 if Present (Alias (E)) then 6440 Freeze_And_Append (Alias (E), N, Result); 6441 end if; 6442 6443 -- We don't freeze internal subprograms, because we don't normally 6444 -- want addition of extra formals or mechanism setting to happen 6445 -- for those. However we do pass through predefined dispatching 6446 -- cases, since extra formals may be needed in some cases, such as 6447 -- for the stream 'Input function (build-in-place formals). 6448 6449 if not Is_Internal (E) 6450 or else Is_Predefined_Dispatching_Operation (E) 6451 then 6452 Freeze_Subprogram (E); 6453 end if; 6454 6455 -- If warning on suspicious contracts then check for the case of 6456 -- a postcondition other than False for a No_Return subprogram. 6457 6458 if No_Return (E) 6459 and then Warn_On_Suspicious_Contract 6460 and then Present (Contract (E)) 6461 then 6462 declare 6463 Prag : Node_Id := Pre_Post_Conditions (Contract (E)); 6464 Exp : Node_Id; 6465 6466 begin 6467 while Present (Prag) loop 6468 if Pragma_Name_Unmapped (Prag) in Name_Post 6469 | Name_Postcondition 6470 | Name_Refined_Post 6471 then 6472 Exp := 6473 Expression 6474 (First (Pragma_Argument_Associations (Prag))); 6475 6476 if Nkind (Exp) /= N_Identifier 6477 or else Chars (Exp) /= Name_False 6478 then 6479 Error_Msg_NE 6480 ("useless postcondition, & is marked " 6481 & "No_Return?.t?", Exp, E); 6482 end if; 6483 end if; 6484 6485 Prag := Next_Pragma (Prag); 6486 end loop; 6487 end; 6488 end if; 6489 6490 -- Here for other than a subprogram or type 6491 6492 else 6493 -- If entity has a type declared in the current scope, and it is 6494 -- not a generic unit, then freeze it first. 6495 6496 if Present (Etype (E)) 6497 and then Ekind (E) /= E_Generic_Function 6498 and then Within_Scope (Etype (E), Current_Scope) 6499 then 6500 Freeze_And_Append (Etype (E), N, Result); 6501 6502 -- For an object of an anonymous array type, aspects on the 6503 -- object declaration apply to the type itself. This is the 6504 -- case for Atomic_Components, Volatile_Components, and 6505 -- Independent_Components. In these cases analysis of the 6506 -- generated pragma will mark the anonymous types accordingly, 6507 -- and the object itself does not require a freeze node. 6508 6509 if Ekind (E) = E_Variable 6510 and then Is_Itype (Etype (E)) 6511 and then Is_Array_Type (Etype (E)) 6512 and then Has_Delayed_Aspects (E) 6513 then 6514 Set_Has_Delayed_Aspects (E, False); 6515 Set_Has_Delayed_Freeze (E, False); 6516 Set_Freeze_Node (E, Empty); 6517 end if; 6518 end if; 6519 6520 -- Special processing for objects created by object declaration 6521 6522 if Nkind (Declaration_Node (E)) = N_Object_Declaration then 6523 Freeze_Object_Declaration (E); 6524 end if; 6525 6526 -- Check that a constant which has a pragma Volatile[_Components] 6527 -- or Atomic[_Components] also has a pragma Import (RM C.6(13)). 6528 6529 -- Note: Atomic[_Components] also sets Volatile[_Components] 6530 6531 if Ekind (E) = E_Constant 6532 and then (Has_Volatile_Components (E) or else Is_Volatile (E)) 6533 and then not Is_Imported (E) 6534 and then not Has_Boolean_Aspect_Import (E) 6535 then 6536 -- Make sure we actually have a pragma, and have not merely 6537 -- inherited the indication from elsewhere (e.g. an address 6538 -- clause, which is not good enough in RM terms). 6539 6540 if Has_Rep_Pragma (E, Name_Atomic) 6541 or else 6542 Has_Rep_Pragma (E, Name_Atomic_Components) 6543 then 6544 Error_Msg_N 6545 ("standalone atomic constant must be " & 6546 "imported (RM C.6(13))", E); 6547 6548 elsif Has_Rep_Pragma (E, Name_Volatile) 6549 or else 6550 Has_Rep_Pragma (E, Name_Volatile_Components) 6551 then 6552 Error_Msg_N 6553 ("standalone volatile constant must be " & 6554 "imported (RM C.6(13))", E); 6555 end if; 6556 end if; 6557 6558 -- Static objects require special handling 6559 6560 if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable) 6561 and then Is_Statically_Allocated (E) 6562 then 6563 Freeze_Static_Object (E); 6564 end if; 6565 6566 -- Remaining step is to layout objects 6567 6568 if Ekind (E) in E_Variable | E_Constant | E_Loop_Parameter 6569 or else Is_Formal (E) 6570 then 6571 Layout_Object (E); 6572 end if; 6573 6574 -- For an object that does not have delayed freezing, and whose 6575 -- initialization actions have been captured in a compound 6576 -- statement, move them back now directly within the enclosing 6577 -- statement sequence. 6578 6579 if Ekind (E) in E_Constant | E_Variable 6580 and then not Has_Delayed_Freeze (E) 6581 then 6582 Explode_Initialization_Compound_Statement (E); 6583 end if; 6584 6585 -- Do not generate a freeze node for a generic unit 6586 6587 if Is_Generic_Unit (E) then 6588 Result := No_List; 6589 goto Leave; 6590 end if; 6591 end if; 6592 6593 -- Case of a type or subtype being frozen 6594 6595 else 6596 -- Verify several SPARK legality rules related to Ghost types now 6597 -- that the type is frozen. 6598 6599 Check_Ghost_Type (E); 6600 6601 -- We used to check here that a full type must have preelaborable 6602 -- initialization if it completes a private type specified with 6603 -- pragma Preelaborable_Initialization, but that missed cases where 6604 -- the types occur within a generic package, since the freezing 6605 -- that occurs within a containing scope generally skips traversal 6606 -- of a generic unit's declarations (those will be frozen within 6607 -- instances). This check was moved to Analyze_Package_Specification. 6608 6609 -- The type may be defined in a generic unit. This can occur when 6610 -- freezing a generic function that returns the type (which is 6611 -- defined in a parent unit). It is clearly meaningless to freeze 6612 -- this type. However, if it is a subtype, its size may be determi- 6613 -- nable and used in subsequent checks, so might as well try to 6614 -- compute it. 6615 6616 -- In Ada 2012, Freeze_Entities is also used in the front end to 6617 -- trigger the analysis of aspect expressions, so in this case we 6618 -- want to continue the freezing process. 6619 6620 -- Is_Generic_Unit (Scope (E)) is dubious here, do we want instead 6621 -- In_Generic_Scope (E)??? 6622 6623 if Present (Scope (E)) 6624 and then Is_Generic_Unit (Scope (E)) 6625 and then 6626 (not Has_Predicates (E) 6627 and then not Has_Delayed_Freeze (E)) 6628 then 6629 Check_Compile_Time_Size (E); 6630 Result := No_List; 6631 goto Leave; 6632 end if; 6633 6634 -- Check for error of Type_Invariant'Class applied to an untagged 6635 -- type (check delayed to freeze time when full type is available). 6636 6637 declare 6638 Prag : constant Node_Id := Get_Pragma (E, Pragma_Invariant); 6639 begin 6640 if Present (Prag) 6641 and then Class_Present (Prag) 6642 and then not Is_Tagged_Type (E) 6643 then 6644 Error_Msg_NE 6645 ("Type_Invariant''Class cannot be specified for &", Prag, E); 6646 Error_Msg_N 6647 ("\can only be specified for a tagged type", Prag); 6648 end if; 6649 end; 6650 6651 -- Deal with special cases of freezing for subtype 6652 6653 if E /= Base_Type (E) then 6654 6655 -- Before we do anything else, a specific test for the case of a 6656 -- size given for an array where the array would need to be packed 6657 -- in order for the size to be honored, but is not. This is the 6658 -- case where implicit packing may apply. The reason we do this so 6659 -- early is that, if we have implicit packing, the layout of the 6660 -- base type is affected, so we must do this before we freeze the 6661 -- base type. 6662 6663 -- We could do this processing only if implicit packing is enabled 6664 -- since in all other cases, the error would be caught by the back 6665 -- end. However, we choose to do the check even if we do not have 6666 -- implicit packing enabled, since this allows us to give a more 6667 -- useful error message (advising use of pragma Implicit_Packing 6668 -- or pragma Pack). 6669 6670 if Is_Array_Type (E) then 6671 declare 6672 Ctyp : constant Entity_Id := Component_Type (E); 6673 Rsiz : constant Uint := 6674 (if Known_RM_Size (Ctyp) then RM_Size (Ctyp) else Uint_0); 6675 SZ : constant Node_Id := Size_Clause (E); 6676 Btyp : constant Entity_Id := Base_Type (E); 6677 6678 Lo : Node_Id; 6679 Hi : Node_Id; 6680 Indx : Node_Id; 6681 6682 Dim : Uint; 6683 Num_Elmts : Uint := Uint_1; 6684 -- Number of elements in array 6685 6686 begin 6687 -- Check enabling conditions. These are straightforward 6688 -- except for the test for a limited composite type. This 6689 -- eliminates the rare case of a array of limited components 6690 -- where there are issues of whether or not we can go ahead 6691 -- and pack the array (since we can't freely pack and unpack 6692 -- arrays if they are limited). 6693 6694 -- Note that we check the root type explicitly because the 6695 -- whole point is we are doing this test before we have had 6696 -- a chance to freeze the base type (and it is that freeze 6697 -- action that causes stuff to be inherited). 6698 6699 -- The conditions on the size are identical to those used in 6700 -- Freeze_Array_Type to set the Is_Packed flag. 6701 6702 if Has_Size_Clause (E) 6703 and then Known_Static_RM_Size (E) 6704 and then not Is_Packed (E) 6705 and then not Has_Pragma_Pack (E) 6706 and then not Has_Component_Size_Clause (E) 6707 and then Known_Static_RM_Size (Ctyp) 6708 and then Rsiz <= System_Max_Integer_Size 6709 and then not (Addressable (Rsiz) 6710 and then Known_Static_Esize (Ctyp) 6711 and then Esize (Ctyp) = Rsiz) 6712 and then not (Rsiz mod System_Storage_Unit = 0 6713 and then Is_Composite_Type (Ctyp)) 6714 and then not Is_Limited_Composite (E) 6715 and then not Is_Packed (Root_Type (E)) 6716 and then not Has_Component_Size_Clause (Root_Type (E)) 6717 and then not (CodePeer_Mode or GNATprove_Mode) 6718 then 6719 -- Compute number of elements in array 6720 6721 Indx := First_Index (E); 6722 while Present (Indx) loop 6723 Get_Index_Bounds (Indx, Lo, Hi); 6724 6725 if not (Compile_Time_Known_Value (Lo) 6726 and then 6727 Compile_Time_Known_Value (Hi)) 6728 then 6729 goto No_Implicit_Packing; 6730 end if; 6731 6732 Dim := Expr_Value (Hi) - Expr_Value (Lo) + 1; 6733 6734 if Dim > Uint_0 then 6735 Num_Elmts := Num_Elmts * Dim; 6736 else 6737 Num_Elmts := Uint_0; 6738 end if; 6739 6740 Next_Index (Indx); 6741 end loop; 6742 6743 -- What we are looking for here is the situation where 6744 -- the RM_Size given would be exactly right if there was 6745 -- a pragma Pack, resulting in the component size being 6746 -- the RM_Size of the component type. 6747 6748 if RM_Size (E) = Num_Elmts * Rsiz then 6749 6750 -- For implicit packing mode, just set the component 6751 -- size and Freeze_Array_Type will do the rest. 6752 6753 if Implicit_Packing then 6754 Set_Component_Size (Btyp, Rsiz); 6755 6756 -- Otherwise give an error message, except that if the 6757 -- specified Size is zero, there is no need for pragma 6758 -- Pack. Note that size zero is not considered 6759 -- Addressable. 6760 6761 elsif RM_Size (E) /= Uint_0 then 6762 Error_Msg_NE 6763 ("size given for& too small", SZ, E); 6764 Error_Msg_N -- CODEFIX 6765 ("\use explicit pragma Pack or use pragma " 6766 & "Implicit_Packing", SZ); 6767 end if; 6768 end if; 6769 end if; 6770 end; 6771 end if; 6772 6773 <<No_Implicit_Packing>> 6774 6775 -- If ancestor subtype present, freeze that first. Note that this 6776 -- will also get the base type frozen. Need RM reference ??? 6777 6778 Atype := Ancestor_Subtype (E); 6779 6780 if Present (Atype) then 6781 Freeze_And_Append (Atype, N, Result); 6782 6783 -- No ancestor subtype present 6784 6785 else 6786 -- See if we have a nearest ancestor that has a predicate. 6787 -- That catches the case of derived type with a predicate. 6788 -- Need RM reference here ??? 6789 6790 Atype := Nearest_Ancestor (E); 6791 6792 if Present (Atype) and then Has_Predicates (Atype) then 6793 Freeze_And_Append (Atype, N, Result); 6794 end if; 6795 6796 -- Freeze base type before freezing the entity (RM 13.14(15)) 6797 6798 if E /= Base_Type (E) then 6799 Freeze_And_Append (Base_Type (E), N, Result); 6800 end if; 6801 end if; 6802 6803 -- A subtype inherits all the type-related representation aspects 6804 -- from its parents (RM 13.1(8)). 6805 6806 Inherit_Aspects_At_Freeze_Point (E); 6807 6808 -- For a derived type, freeze its parent type first (RM 13.14(15)) 6809 6810 elsif Is_Derived_Type (E) then 6811 Freeze_And_Append (Etype (E), N, Result); 6812 Freeze_And_Append (First_Subtype (Etype (E)), N, Result); 6813 6814 -- A derived type inherits each type-related representation aspect 6815 -- of its parent type that was directly specified before the 6816 -- declaration of the derived type (RM 13.1(15)). 6817 6818 Inherit_Aspects_At_Freeze_Point (E); 6819 end if; 6820 6821 -- Case of array type 6822 6823 if Is_Array_Type (E) then 6824 Freeze_Array_Type (E); 6825 end if; 6826 6827 -- Check for incompatible size and alignment for array/record type 6828 6829 if Warn_On_Size_Alignment 6830 and then (Is_Array_Type (E) or else Is_Record_Type (E)) 6831 and then Has_Size_Clause (E) 6832 and then Has_Alignment_Clause (E) 6833 6834 -- If explicit Object_Size clause given assume that the programmer 6835 -- knows what he is doing, and expects the compiler behavior. 6836 6837 and then not Has_Object_Size_Clause (E) 6838 6839 -- It does not really make sense to warn for the minimum alignment 6840 -- since the programmer could not get rid of the warning. 6841 6842 and then Alignment (E) > 1 6843 6844 -- Check for size not a multiple of alignment 6845 6846 and then RM_Size (E) mod (Alignment (E) * System_Storage_Unit) /= 0 6847 then 6848 declare 6849 SC : constant Node_Id := Size_Clause (E); 6850 AC : constant Node_Id := Alignment_Clause (E); 6851 Loc : Node_Id; 6852 Abits : constant Uint := Alignment (E) * System_Storage_Unit; 6853 6854 begin 6855 if Present (SC) and then Present (AC) then 6856 6857 -- Give a warning 6858 6859 if Sloc (SC) > Sloc (AC) then 6860 Loc := SC; 6861 Error_Msg_NE 6862 ("?.z?size is not a multiple of alignment for &", 6863 Loc, E); 6864 Error_Msg_Sloc := Sloc (AC); 6865 Error_Msg_Uint_1 := Alignment (E); 6866 Error_Msg_N ("\?.z?alignment of ^ specified #", Loc); 6867 6868 else 6869 Loc := AC; 6870 Error_Msg_NE 6871 ("?.z?size is not a multiple of alignment for &", 6872 Loc, E); 6873 Error_Msg_Sloc := Sloc (SC); 6874 Error_Msg_Uint_1 := RM_Size (E); 6875 Error_Msg_N ("\?.z?size of ^ specified #", Loc); 6876 end if; 6877 6878 Error_Msg_Uint_1 := ((RM_Size (E) / Abits) + 1) * Abits; 6879 Error_Msg_N ("\?.z?Object_Size will be increased to ^", Loc); 6880 end if; 6881 end; 6882 end if; 6883 6884 -- For a class-wide type, the corresponding specific type is 6885 -- frozen as well (RM 13.14(15)) 6886 6887 if Is_Class_Wide_Type (E) then 6888 Freeze_And_Append (Root_Type (E), N, Result); 6889 6890 -- If the base type of the class-wide type is still incomplete, 6891 -- the class-wide remains unfrozen as well. This is legal when 6892 -- E is the formal of a primitive operation of some other type 6893 -- which is being frozen. 6894 6895 if not Is_Frozen (Root_Type (E)) then 6896 Set_Is_Frozen (E, False); 6897 goto Leave; 6898 end if; 6899 6900 -- The equivalent type associated with a class-wide subtype needs 6901 -- to be frozen to ensure that its layout is done. 6902 6903 if Ekind (E) = E_Class_Wide_Subtype 6904 and then Present (Equivalent_Type (E)) 6905 then 6906 Freeze_And_Append (Equivalent_Type (E), N, Result); 6907 end if; 6908 6909 -- Generate an itype reference for a library-level class-wide type 6910 -- at the freeze point. Otherwise the first explicit reference to 6911 -- the type may appear in an inner scope which will be rejected by 6912 -- the back-end. 6913 6914 if Is_Itype (E) 6915 and then Is_Compilation_Unit (Scope (E)) 6916 then 6917 declare 6918 Ref : constant Node_Id := Make_Itype_Reference (Loc); 6919 6920 begin 6921 Set_Itype (Ref, E); 6922 6923 -- From a gigi point of view, a class-wide subtype derives 6924 -- from its record equivalent type. As a result, the itype 6925 -- reference must appear after the freeze node of the 6926 -- equivalent type or gigi will reject the reference. 6927 6928 if Ekind (E) = E_Class_Wide_Subtype 6929 and then Present (Equivalent_Type (E)) 6930 then 6931 Insert_After (Freeze_Node (Equivalent_Type (E)), Ref); 6932 else 6933 Add_To_Result (Ref); 6934 end if; 6935 end; 6936 end if; 6937 6938 -- For a record type or record subtype, freeze all component types 6939 -- (RM 13.14(15)). We test for E_Record_(sub)Type here, rather than 6940 -- using Is_Record_Type, because we don't want to attempt the freeze 6941 -- for the case of a private type with record extension (we will do 6942 -- that later when the full type is frozen). 6943 6944 elsif Ekind (E) in E_Record_Type | E_Record_Subtype then 6945 if not In_Generic_Scope (E) then 6946 Freeze_Record_Type (E); 6947 end if; 6948 6949 -- Report a warning if a discriminated record base type has a 6950 -- convention with language C or C++ applied to it. This check is 6951 -- done even within generic scopes (but not in instantiations), 6952 -- which is why we don't do it as part of Freeze_Record_Type. 6953 6954 Check_Suspicious_Convention (E); 6955 6956 -- For a concurrent type, freeze corresponding record type. This does 6957 -- not correspond to any specific rule in the RM, but the record type 6958 -- is essentially part of the concurrent type. Also freeze all local 6959 -- entities. This includes record types created for entry parameter 6960 -- blocks and whatever local entities may appear in the private part. 6961 6962 elsif Is_Concurrent_Type (E) then 6963 if Present (Corresponding_Record_Type (E)) then 6964 Freeze_And_Append (Corresponding_Record_Type (E), N, Result); 6965 end if; 6966 6967 Comp := First_Entity (E); 6968 while Present (Comp) loop 6969 if Is_Type (Comp) then 6970 Freeze_And_Append (Comp, N, Result); 6971 6972 elsif (Ekind (Comp)) /= E_Function then 6973 6974 -- The guard on the presence of the Etype seems to be needed 6975 -- for some CodePeer (-gnatcC) cases, but not clear why??? 6976 6977 if Present (Etype (Comp)) then 6978 if Is_Itype (Etype (Comp)) 6979 and then Underlying_Type (Scope (Etype (Comp))) = E 6980 then 6981 Undelay_Type (Etype (Comp)); 6982 end if; 6983 6984 Freeze_And_Append (Etype (Comp), N, Result); 6985 end if; 6986 end if; 6987 6988 Next_Entity (Comp); 6989 end loop; 6990 6991 -- Private types are required to point to the same freeze node as 6992 -- their corresponding full views. The freeze node itself has to 6993 -- point to the partial view of the entity (because from the partial 6994 -- view, we can retrieve the full view, but not the reverse). 6995 -- However, in order to freeze correctly, we need to freeze the full 6996 -- view. If we are freezing at the end of a scope (or within the 6997 -- scope) of the private type, the partial and full views will have 6998 -- been swapped, the full view appears first in the entity chain and 6999 -- the swapping mechanism ensures that the pointers are properly set 7000 -- (on scope exit). 7001 7002 -- If we encounter the partial view before the full view (e.g. when 7003 -- freezing from another scope), we freeze the full view, and then 7004 -- set the pointers appropriately since we cannot rely on swapping to 7005 -- fix things up (subtypes in an outer scope might not get swapped). 7006 7007 -- If the full view is itself private, the above requirements apply 7008 -- to the underlying full view instead of the full view. But there is 7009 -- no swapping mechanism for the underlying full view so we need to 7010 -- set the pointers appropriately in both cases. 7011 7012 elsif Is_Incomplete_Or_Private_Type (E) 7013 and then not Is_Generic_Type (E) 7014 then 7015 -- The construction of the dispatch table associated with library 7016 -- level tagged types forces freezing of all the primitives of the 7017 -- type, which may cause premature freezing of the partial view. 7018 -- For example: 7019 7020 -- package Pkg is 7021 -- type T is tagged private; 7022 -- type DT is new T with private; 7023 -- procedure Prim (X : in out T; Y : in out DT'Class); 7024 -- private 7025 -- type T is tagged null record; 7026 -- Obj : T; 7027 -- type DT is new T with null record; 7028 -- end; 7029 7030 -- In this case the type will be frozen later by the usual 7031 -- mechanism: an object declaration, an instantiation, or the 7032 -- end of a declarative part. 7033 7034 if Is_Library_Level_Tagged_Type (E) 7035 and then not Present (Full_View (E)) 7036 then 7037 Set_Is_Frozen (E, False); 7038 goto Leave; 7039 7040 -- Case of full view present 7041 7042 elsif Present (Full_View (E)) then 7043 7044 -- If full view has already been frozen, then no further 7045 -- processing is required 7046 7047 if Is_Frozen (Full_View (E)) then 7048 Set_Has_Delayed_Freeze (E, False); 7049 Set_Freeze_Node (E, Empty); 7050 7051 -- Otherwise freeze full view and patch the pointers so that 7052 -- the freeze node will elaborate both views in the back end. 7053 -- However, if full view is itself private, freeze underlying 7054 -- full view instead and patch the pointers so that the freeze 7055 -- node will elaborate the three views in the back end. 7056 7057 else 7058 declare 7059 Full : Entity_Id := Full_View (E); 7060 7061 begin 7062 if Is_Private_Type (Full) 7063 and then Present (Underlying_Full_View (Full)) 7064 then 7065 Full := Underlying_Full_View (Full); 7066 end if; 7067 7068 Freeze_And_Append (Full, N, Result); 7069 7070 if Full /= Full_View (E) 7071 and then Has_Delayed_Freeze (Full_View (E)) 7072 then 7073 F_Node := Freeze_Node (Full); 7074 7075 if Present (F_Node) then 7076 Inherit_Freeze_Node 7077 (Fnod => F_Node, Typ => Full_View (E)); 7078 else 7079 Set_Has_Delayed_Freeze (Full_View (E), False); 7080 Set_Freeze_Node (Full_View (E), Empty); 7081 end if; 7082 end if; 7083 7084 if Has_Delayed_Freeze (E) then 7085 F_Node := Freeze_Node (Full_View (E)); 7086 7087 if Present (F_Node) then 7088 Inherit_Freeze_Node (Fnod => F_Node, Typ => E); 7089 else 7090 -- {Incomplete,Private}_Subtypes with Full_Views 7091 -- constrained by discriminants. 7092 7093 Set_Has_Delayed_Freeze (E, False); 7094 Set_Freeze_Node (E, Empty); 7095 end if; 7096 end if; 7097 end; 7098 end if; 7099 7100 Check_Debug_Info_Needed (E); 7101 7102 -- AI-117 requires that the convention of a partial view be the 7103 -- same as the convention of the full view. Note that this is a 7104 -- recognized breach of privacy, but it's essential for logical 7105 -- consistency of representation, and the lack of a rule in 7106 -- RM95 was an oversight. 7107 7108 Set_Convention (E, Convention (Full_View (E))); 7109 7110 Set_Size_Known_At_Compile_Time (E, 7111 Size_Known_At_Compile_Time (Full_View (E))); 7112 7113 -- Size information is copied from the full view to the 7114 -- incomplete or private view for consistency. 7115 7116 -- We skip this is the full view is not a type. This is very 7117 -- strange of course, and can only happen as a result of 7118 -- certain illegalities, such as a premature attempt to derive 7119 -- from an incomplete type. 7120 7121 if Is_Type (Full_View (E)) then 7122 Set_Size_Info (E, Full_View (E)); 7123 Copy_RM_Size (To => E, From => Full_View (E)); 7124 end if; 7125 7126 goto Leave; 7127 7128 -- Case of underlying full view present 7129 7130 elsif Is_Private_Type (E) 7131 and then Present (Underlying_Full_View (E)) 7132 then 7133 if not Is_Frozen (Underlying_Full_View (E)) then 7134 Freeze_And_Append (Underlying_Full_View (E), N, Result); 7135 end if; 7136 7137 -- Patch the pointers so that the freeze node will elaborate 7138 -- both views in the back end. 7139 7140 if Has_Delayed_Freeze (E) then 7141 F_Node := Freeze_Node (Underlying_Full_View (E)); 7142 7143 if Present (F_Node) then 7144 Inherit_Freeze_Node 7145 (Fnod => F_Node, 7146 Typ => E); 7147 else 7148 Set_Has_Delayed_Freeze (E, False); 7149 Set_Freeze_Node (E, Empty); 7150 end if; 7151 end if; 7152 7153 Check_Debug_Info_Needed (E); 7154 7155 goto Leave; 7156 7157 -- Case of no full view present. If entity is subtype or derived, 7158 -- it is safe to freeze, correctness depends on the frozen status 7159 -- of parent. Otherwise it is either premature usage, or a Taft 7160 -- amendment type, so diagnosis is at the point of use and the 7161 -- type might be frozen later. 7162 7163 elsif E /= Base_Type (E) then 7164 declare 7165 Btyp : constant Entity_Id := Base_Type (E); 7166 7167 begin 7168 -- However, if the base type is itself private and has no 7169 -- (underlying) full view either, wait until the full type 7170 -- declaration is seen and all the full views are created. 7171 7172 if Is_Private_Type (Btyp) 7173 and then No (Full_View (Btyp)) 7174 and then No (Underlying_Full_View (Btyp)) 7175 and then Has_Delayed_Freeze (Btyp) 7176 and then No (Freeze_Node (Btyp)) 7177 then 7178 Set_Is_Frozen (E, False); 7179 Result := No_List; 7180 goto Leave; 7181 end if; 7182 end; 7183 7184 elsif Is_Derived_Type (E) then 7185 null; 7186 7187 else 7188 Set_Is_Frozen (E, False); 7189 Result := No_List; 7190 goto Leave; 7191 end if; 7192 7193 -- For access subprogram, freeze types of all formals, the return 7194 -- type was already frozen, since it is the Etype of the function. 7195 -- Formal types can be tagged Taft amendment types, but otherwise 7196 -- they cannot be incomplete. 7197 7198 elsif Ekind (E) = E_Subprogram_Type then 7199 Formal := First_Formal (E); 7200 while Present (Formal) loop 7201 if Ekind (Etype (Formal)) = E_Incomplete_Type 7202 and then No (Full_View (Etype (Formal))) 7203 then 7204 if Is_Tagged_Type (Etype (Formal)) then 7205 null; 7206 7207 -- AI05-151: Incomplete types are allowed in access to 7208 -- subprogram specifications. 7209 7210 elsif Ada_Version < Ada_2012 then 7211 Error_Msg_NE 7212 ("invalid use of incomplete type&", E, Etype (Formal)); 7213 end if; 7214 end if; 7215 7216 Freeze_And_Append (Etype (Formal), N, Result); 7217 Next_Formal (Formal); 7218 end loop; 7219 7220 Freeze_Subprogram (E); 7221 7222 -- For access to a protected subprogram, freeze the equivalent type 7223 -- (however this is not set if we are not generating code or if this 7224 -- is an anonymous type used just for resolution). 7225 7226 elsif Is_Access_Protected_Subprogram_Type (E) then 7227 if Present (Equivalent_Type (E)) then 7228 Freeze_And_Append (Equivalent_Type (E), N, Result); 7229 end if; 7230 end if; 7231 7232 -- Generic types are never seen by the back-end, and are also not 7233 -- processed by the expander (since the expander is turned off for 7234 -- generic processing), so we never need freeze nodes for them. 7235 7236 if Is_Generic_Type (E) then 7237 goto Leave; 7238 end if; 7239 7240 -- Some special processing for non-generic types to complete 7241 -- representation details not known till the freeze point. 7242 7243 if Is_Fixed_Point_Type (E) then 7244 Freeze_Fixed_Point_Type (E); 7245 7246 elsif Is_Enumeration_Type (E) then 7247 Freeze_Enumeration_Type (E); 7248 7249 elsif Is_Integer_Type (E) then 7250 Adjust_Esize_For_Alignment (E); 7251 7252 if Is_Modular_Integer_Type (E) 7253 and then Warn_On_Suspicious_Modulus_Value 7254 then 7255 Check_Suspicious_Modulus (E); 7256 end if; 7257 7258 -- The pool applies to named and anonymous access types, but not 7259 -- to subprogram and to internal types generated for 'Access 7260 -- references. 7261 7262 elsif Is_Access_Object_Type (E) 7263 and then Ekind (E) /= E_Access_Attribute_Type 7264 then 7265 -- If a pragma Default_Storage_Pool applies, and this type has no 7266 -- Storage_Pool or Storage_Size clause (which must have occurred 7267 -- before the freezing point), then use the default. This applies 7268 -- only to base types. 7269 7270 -- None of this applies to access to subprograms, for which there 7271 -- are clearly no pools. 7272 7273 if Present (Default_Pool) 7274 and then Is_Base_Type (E) 7275 and then not Has_Storage_Size_Clause (E) 7276 and then No (Associated_Storage_Pool (E)) 7277 then 7278 -- Case of pragma Default_Storage_Pool (null) 7279 7280 if Nkind (Default_Pool) = N_Null then 7281 Set_No_Pool_Assigned (E); 7282 7283 -- Case of pragma Default_Storage_Pool (Standard) 7284 7285 elsif Entity (Default_Pool) = Standard_Standard then 7286 Set_Associated_Storage_Pool (E, RTE (RE_Global_Pool_Object)); 7287 7288 -- Case of pragma Default_Storage_Pool (storage_pool_NAME) 7289 7290 else 7291 Set_Associated_Storage_Pool (E, Entity (Default_Pool)); 7292 end if; 7293 end if; 7294 7295 -- Check restriction for standard storage pool 7296 7297 if No (Associated_Storage_Pool (E)) then 7298 Check_Restriction (No_Standard_Storage_Pools, E); 7299 end if; 7300 7301 -- Deal with error message for pure access type. This is not an 7302 -- error in Ada 2005 if there is no pool (see AI-366). 7303 7304 if Is_Pure_Unit_Access_Type (E) 7305 and then (Ada_Version < Ada_2005 7306 or else not No_Pool_Assigned (E)) 7307 and then not Is_Generic_Unit (Scope (E)) 7308 then 7309 Error_Msg_N ("named access type not allowed in pure unit", E); 7310 7311 if Ada_Version >= Ada_2005 then 7312 Error_Msg_N 7313 ("\would be legal if Storage_Size of 0 given??", E); 7314 7315 elsif No_Pool_Assigned (E) then 7316 Error_Msg_N 7317 ("\would be legal in Ada 2005??", E); 7318 7319 else 7320 Error_Msg_N 7321 ("\would be legal in Ada 2005 if " 7322 & "Storage_Size of 0 given??", E); 7323 end if; 7324 end if; 7325 end if; 7326 7327 -- Case of composite types 7328 7329 if Is_Composite_Type (E) then 7330 7331 -- AI-117 requires that all new primitives of a tagged type must 7332 -- inherit the convention of the full view of the type. Inherited 7333 -- and overriding operations are defined to inherit the convention 7334 -- of their parent or overridden subprogram (also specified in 7335 -- AI-117), which will have occurred earlier (in Derive_Subprogram 7336 -- and New_Overloaded_Entity). Here we set the convention of 7337 -- primitives that are still convention Ada, which will ensure 7338 -- that any new primitives inherit the type's convention. Class- 7339 -- wide types can have a foreign convention inherited from their 7340 -- specific type, but are excluded from this since they don't have 7341 -- any associated primitives. 7342 7343 if Is_Tagged_Type (E) 7344 and then not Is_Class_Wide_Type (E) 7345 and then Convention (E) /= Convention_Ada 7346 then 7347 declare 7348 Prim_List : constant Elist_Id := Primitive_Operations (E); 7349 Prim : Elmt_Id; 7350 7351 begin 7352 Prim := First_Elmt (Prim_List); 7353 while Present (Prim) loop 7354 if Convention (Node (Prim)) = Convention_Ada then 7355 Set_Convention (Node (Prim), Convention (E)); 7356 end if; 7357 7358 Next_Elmt (Prim); 7359 end loop; 7360 end; 7361 end if; 7362 7363 -- If the type is a simple storage pool type, then this is where 7364 -- we attempt to locate and validate its Allocate, Deallocate, and 7365 -- Storage_Size operations (the first is required, and the latter 7366 -- two are optional). We also verify that the full type for a 7367 -- private type is allowed to be a simple storage pool type. 7368 7369 if Present (Get_Rep_Pragma (E, Name_Simple_Storage_Pool_Type)) 7370 and then (Is_Base_Type (E) or else Has_Private_Declaration (E)) 7371 then 7372 -- If the type is marked Has_Private_Declaration, then this is 7373 -- a full type for a private type that was specified with the 7374 -- pragma Simple_Storage_Pool_Type, and here we ensure that the 7375 -- pragma is allowed for the full type (for example, it can't 7376 -- be an array type, or a nonlimited record type). 7377 7378 if Has_Private_Declaration (E) then 7379 if (not Is_Record_Type (E) or else not Is_Limited_View (E)) 7380 and then not Is_Private_Type (E) 7381 then 7382 Error_Msg_Name_1 := Name_Simple_Storage_Pool_Type; 7383 Error_Msg_N 7384 ("pragma% can only apply to full type that is an " & 7385 "explicitly limited type", E); 7386 end if; 7387 end if; 7388 7389 Validate_Simple_Pool_Ops : declare 7390 Pool_Type : Entity_Id renames E; 7391 Address_Type : constant Entity_Id := RTE (RE_Address); 7392 Stg_Cnt_Type : constant Entity_Id := RTE (RE_Storage_Count); 7393 7394 procedure Validate_Simple_Pool_Op_Formal 7395 (Pool_Op : Entity_Id; 7396 Pool_Op_Formal : in out Entity_Id; 7397 Expected_Mode : Formal_Kind; 7398 Expected_Type : Entity_Id; 7399 Formal_Name : String; 7400 OK_Formal : in out Boolean); 7401 -- Validate one formal Pool_Op_Formal of the candidate pool 7402 -- operation Pool_Op. The formal must be of Expected_Type 7403 -- and have mode Expected_Mode. OK_Formal will be set to 7404 -- False if the formal doesn't match. If OK_Formal is False 7405 -- on entry, then the formal will effectively be ignored 7406 -- (because validation of the pool op has already failed). 7407 -- Upon return, Pool_Op_Formal will be updated to the next 7408 -- formal, if any. 7409 7410 procedure Validate_Simple_Pool_Operation 7411 (Op_Name : Name_Id); 7412 -- Search for and validate a simple pool operation with the 7413 -- name Op_Name. If the name is Allocate, then there must be 7414 -- exactly one such primitive operation for the simple pool 7415 -- type. If the name is Deallocate or Storage_Size, then 7416 -- there can be at most one such primitive operation. The 7417 -- profile of the located primitive must conform to what 7418 -- is expected for each operation. 7419 7420 ------------------------------------ 7421 -- Validate_Simple_Pool_Op_Formal -- 7422 ------------------------------------ 7423 7424 procedure Validate_Simple_Pool_Op_Formal 7425 (Pool_Op : Entity_Id; 7426 Pool_Op_Formal : in out Entity_Id; 7427 Expected_Mode : Formal_Kind; 7428 Expected_Type : Entity_Id; 7429 Formal_Name : String; 7430 OK_Formal : in out Boolean) 7431 is 7432 begin 7433 -- If OK_Formal is False on entry, then simply ignore 7434 -- the formal, because an earlier formal has already 7435 -- been flagged. 7436 7437 if not OK_Formal then 7438 return; 7439 7440 -- If no formal is passed in, then issue an error for a 7441 -- missing formal. 7442 7443 elsif not Present (Pool_Op_Formal) then 7444 Error_Msg_NE 7445 ("simple storage pool op missing formal " & 7446 Formal_Name & " of type&", Pool_Op, Expected_Type); 7447 OK_Formal := False; 7448 7449 return; 7450 end if; 7451 7452 if Etype (Pool_Op_Formal) /= Expected_Type then 7453 7454 -- If the pool type was expected for this formal, then 7455 -- this will not be considered a candidate operation 7456 -- for the simple pool, so we unset OK_Formal so that 7457 -- the op and any later formals will be ignored. 7458 7459 if Expected_Type = Pool_Type then 7460 OK_Formal := False; 7461 7462 return; 7463 7464 else 7465 Error_Msg_NE 7466 ("wrong type for formal " & Formal_Name & 7467 " of simple storage pool op; expected type&", 7468 Pool_Op_Formal, Expected_Type); 7469 end if; 7470 end if; 7471 7472 -- Issue error if formal's mode is not the expected one 7473 7474 if Ekind (Pool_Op_Formal) /= Expected_Mode then 7475 Error_Msg_N 7476 ("wrong mode for formal of simple storage pool op", 7477 Pool_Op_Formal); 7478 end if; 7479 7480 -- Advance to the next formal 7481 7482 Next_Formal (Pool_Op_Formal); 7483 end Validate_Simple_Pool_Op_Formal; 7484 7485 ------------------------------------ 7486 -- Validate_Simple_Pool_Operation -- 7487 ------------------------------------ 7488 7489 procedure Validate_Simple_Pool_Operation 7490 (Op_Name : Name_Id) 7491 is 7492 Op : Entity_Id; 7493 Found_Op : Entity_Id := Empty; 7494 Formal : Entity_Id; 7495 Is_OK : Boolean; 7496 7497 begin 7498 pragma Assert 7499 (Op_Name in Name_Allocate 7500 | Name_Deallocate 7501 | Name_Storage_Size); 7502 7503 Error_Msg_Name_1 := Op_Name; 7504 7505 -- For each homonym declared immediately in the scope 7506 -- of the simple storage pool type, determine whether 7507 -- the homonym is an operation of the pool type, and, 7508 -- if so, check that its profile is as expected for 7509 -- a simple pool operation of that name. 7510 7511 Op := Get_Name_Entity_Id (Op_Name); 7512 while Present (Op) loop 7513 if Ekind (Op) in E_Function | E_Procedure 7514 and then Scope (Op) = Current_Scope 7515 then 7516 Formal := First_Entity (Op); 7517 7518 Is_OK := True; 7519 7520 -- The first parameter must be of the pool type 7521 -- in order for the operation to qualify. 7522 7523 if Op_Name = Name_Storage_Size then 7524 Validate_Simple_Pool_Op_Formal 7525 (Op, Formal, E_In_Parameter, Pool_Type, 7526 "Pool", Is_OK); 7527 else 7528 Validate_Simple_Pool_Op_Formal 7529 (Op, Formal, E_In_Out_Parameter, Pool_Type, 7530 "Pool", Is_OK); 7531 end if; 7532 7533 -- If another operation with this name has already 7534 -- been located for the type, then flag an error, 7535 -- since we only allow the type to have a single 7536 -- such primitive. 7537 7538 if Present (Found_Op) and then Is_OK then 7539 Error_Msg_NE 7540 ("only one % operation allowed for " & 7541 "simple storage pool type&", Op, Pool_Type); 7542 end if; 7543 7544 -- In the case of Allocate and Deallocate, a formal 7545 -- of type System.Address is required. 7546 7547 if Op_Name = Name_Allocate then 7548 Validate_Simple_Pool_Op_Formal 7549 (Op, Formal, E_Out_Parameter, 7550 Address_Type, "Storage_Address", Is_OK); 7551 7552 elsif Op_Name = Name_Deallocate then 7553 Validate_Simple_Pool_Op_Formal 7554 (Op, Formal, E_In_Parameter, 7555 Address_Type, "Storage_Address", Is_OK); 7556 end if; 7557 7558 -- In the case of Allocate and Deallocate, formals 7559 -- of type Storage_Count are required as the third 7560 -- and fourth parameters. 7561 7562 if Op_Name /= Name_Storage_Size then 7563 Validate_Simple_Pool_Op_Formal 7564 (Op, Formal, E_In_Parameter, 7565 Stg_Cnt_Type, "Size_In_Storage_Units", Is_OK); 7566 Validate_Simple_Pool_Op_Formal 7567 (Op, Formal, E_In_Parameter, 7568 Stg_Cnt_Type, "Alignment", Is_OK); 7569 end if; 7570 7571 -- If no mismatched formals have been found (Is_OK) 7572 -- and no excess formals are present, then this 7573 -- operation has been validated, so record it. 7574 7575 if not Present (Formal) and then Is_OK then 7576 Found_Op := Op; 7577 end if; 7578 end if; 7579 7580 Op := Homonym (Op); 7581 end loop; 7582 7583 -- There must be a valid Allocate operation for the type, 7584 -- so issue an error if none was found. 7585 7586 if Op_Name = Name_Allocate 7587 and then not Present (Found_Op) 7588 then 7589 Error_Msg_N ("missing % operation for simple " & 7590 "storage pool type", Pool_Type); 7591 7592 elsif Present (Found_Op) then 7593 7594 -- Simple pool operations can't be abstract 7595 7596 if Is_Abstract_Subprogram (Found_Op) then 7597 Error_Msg_N 7598 ("simple storage pool operation must not be " & 7599 "abstract", Found_Op); 7600 end if; 7601 7602 -- The Storage_Size operation must be a function with 7603 -- Storage_Count as its result type. 7604 7605 if Op_Name = Name_Storage_Size then 7606 if Ekind (Found_Op) = E_Procedure then 7607 Error_Msg_N 7608 ("% operation must be a function", Found_Op); 7609 7610 elsif Etype (Found_Op) /= Stg_Cnt_Type then 7611 Error_Msg_NE 7612 ("wrong result type for%, expected type&", 7613 Found_Op, Stg_Cnt_Type); 7614 end if; 7615 7616 -- Allocate and Deallocate must be procedures 7617 7618 elsif Ekind (Found_Op) = E_Function then 7619 Error_Msg_N 7620 ("% operation must be a procedure", Found_Op); 7621 end if; 7622 end if; 7623 end Validate_Simple_Pool_Operation; 7624 7625 -- Start of processing for Validate_Simple_Pool_Ops 7626 7627 begin 7628 Validate_Simple_Pool_Operation (Name_Allocate); 7629 Validate_Simple_Pool_Operation (Name_Deallocate); 7630 Validate_Simple_Pool_Operation (Name_Storage_Size); 7631 end Validate_Simple_Pool_Ops; 7632 end if; 7633 end if; 7634 7635 -- Now that all types from which E may depend are frozen, see if 7636 -- strict alignment is required, a component clause on a record 7637 -- is correct, the size is known at compile time and if it must 7638 -- be unsigned, in that order. 7639 7640 if Base_Type (E) = E then 7641 Check_Strict_Alignment (E); 7642 end if; 7643 7644 if Ekind (E) in E_Record_Type | E_Record_Subtype then 7645 declare 7646 RC : constant Node_Id := Get_Record_Representation_Clause (E); 7647 begin 7648 if Present (RC) then 7649 Check_Record_Representation_Clause (RC); 7650 end if; 7651 end; 7652 end if; 7653 7654 Check_Compile_Time_Size (E); 7655 7656 Check_Unsigned_Type (E); 7657 7658 -- Do not allow a size clause for a type which does not have a size 7659 -- that is known at compile time 7660 7661 if (Has_Size_Clause (E) or else Has_Object_Size_Clause (E)) 7662 and then not Size_Known_At_Compile_Time (E) 7663 then 7664 -- Suppress this message if errors posted on E, even if we are 7665 -- in all errors mode, since this is often a junk message 7666 7667 if not Error_Posted (E) then 7668 Error_Msg_N 7669 ("size clause not allowed for variable length type", 7670 Size_Clause (E)); 7671 end if; 7672 end if; 7673 7674 -- Now we set/verify the representation information, in particular 7675 -- the size and alignment values. This processing is not required for 7676 -- generic types, since generic types do not play any part in code 7677 -- generation, and so the size and alignment values for such types 7678 -- are irrelevant. Ditto for types declared within a generic unit, 7679 -- which may have components that depend on generic parameters, and 7680 -- that will be recreated in an instance. 7681 7682 if Inside_A_Generic then 7683 null; 7684 7685 -- Otherwise we call the layout procedure 7686 7687 else 7688 Layout_Type (E); 7689 end if; 7690 7691 -- If this is an access to subprogram whose designated type is itself 7692 -- a subprogram type, the return type of this anonymous subprogram 7693 -- type must be decorated as well. 7694 7695 if Ekind (E) = E_Anonymous_Access_Subprogram_Type 7696 and then Ekind (Designated_Type (E)) = E_Subprogram_Type 7697 then 7698 Layout_Type (Etype (Designated_Type (E))); 7699 end if; 7700 7701 -- If the type has a Defaut_Value/Default_Component_Value aspect, 7702 -- this is where we analyze the expression (after the type is frozen, 7703 -- since in the case of Default_Value, we are analyzing with the 7704 -- type itself, and we treat Default_Component_Value similarly for 7705 -- the sake of uniformity). 7706 7707 if Is_First_Subtype (E) and then Has_Default_Aspect (E) then 7708 declare 7709 Nam : Name_Id; 7710 Exp : Node_Id; 7711 Typ : Entity_Id; 7712 7713 begin 7714 if Is_Scalar_Type (E) then 7715 Nam := Name_Default_Value; 7716 Typ := E; 7717 Exp := Default_Aspect_Value (Typ); 7718 else 7719 Nam := Name_Default_Component_Value; 7720 Typ := Component_Type (E); 7721 Exp := Default_Aspect_Component_Value (E); 7722 end if; 7723 7724 Analyze_And_Resolve (Exp, Typ); 7725 7726 if Etype (Exp) /= Any_Type then 7727 if not Is_OK_Static_Expression (Exp) then 7728 Error_Msg_Name_1 := Nam; 7729 Flag_Non_Static_Expr 7730 ("aspect% requires static expression", Exp); 7731 end if; 7732 end if; 7733 end; 7734 end if; 7735 7736 -- Verify at this point that No_Controlled_Parts and No_Task_Parts, 7737 -- when specified on the current type or one of its ancestors, has 7738 -- not been overridden and that no violation of the aspect has 7739 -- occurred. 7740 7741 -- It is important that we perform the checks here after the type has 7742 -- been processed because if said type depended on a private type it 7743 -- will not have been marked controlled or having tasks. 7744 7745 Check_No_Parts_Violations (E, Aspect_No_Controlled_Parts); 7746 Check_No_Parts_Violations (E, Aspect_No_Task_Parts); 7747 7748 -- End of freeze processing for type entities 7749 end if; 7750 7751 -- Here is where we logically freeze the current entity. If it has a 7752 -- freeze node, then this is the point at which the freeze node is 7753 -- linked into the result list. 7754 7755 if Has_Delayed_Freeze (E) then 7756 7757 -- If a freeze node is already allocated, use it, otherwise allocate 7758 -- a new one. The preallocation happens in the case of anonymous base 7759 -- types, where we preallocate so that we can set First_Subtype_Link. 7760 -- Note that we reset the Sloc to the current freeze location. 7761 7762 if Present (Freeze_Node (E)) then 7763 F_Node := Freeze_Node (E); 7764 Set_Sloc (F_Node, Loc); 7765 7766 else 7767 F_Node := New_Node (N_Freeze_Entity, Loc); 7768 Set_Freeze_Node (E, F_Node); 7769 Set_Access_Types_To_Process (F_Node, No_Elist); 7770 Set_TSS_Elist (F_Node, No_Elist); 7771 Set_Actions (F_Node, No_List); 7772 end if; 7773 7774 Set_Entity (F_Node, E); 7775 Add_To_Result (F_Node); 7776 7777 -- A final pass over record types with discriminants. If the type 7778 -- has an incomplete declaration, there may be constrained access 7779 -- subtypes declared elsewhere, which do not depend on the discrimi- 7780 -- nants of the type, and which are used as component types (i.e. 7781 -- the full view is a recursive type). The designated types of these 7782 -- subtypes can only be elaborated after the type itself, and they 7783 -- need an itype reference. 7784 7785 if Ekind (E) = E_Record_Type and then Has_Discriminants (E) then 7786 declare 7787 Comp : Entity_Id; 7788 IR : Node_Id; 7789 Typ : Entity_Id; 7790 7791 begin 7792 Comp := First_Component (E); 7793 while Present (Comp) loop 7794 Typ := Etype (Comp); 7795 7796 if Is_Access_Type (Typ) 7797 and then Scope (Typ) /= E 7798 and then Base_Type (Designated_Type (Typ)) = E 7799 and then Is_Itype (Designated_Type (Typ)) 7800 then 7801 IR := Make_Itype_Reference (Sloc (Comp)); 7802 Set_Itype (IR, Designated_Type (Typ)); 7803 Append (IR, Result); 7804 end if; 7805 7806 Next_Component (Comp); 7807 end loop; 7808 end; 7809 end if; 7810 end if; 7811 7812 -- When a type is frozen, the first subtype of the type is frozen as 7813 -- well (RM 13.14(15)). This has to be done after freezing the type, 7814 -- since obviously the first subtype depends on its own base type. 7815 7816 if Is_Type (E) then 7817 Freeze_And_Append (First_Subtype (E), N, Result); 7818 7819 -- If we just froze a tagged non-class-wide record, then freeze the 7820 -- corresponding class-wide type. This must be done after the tagged 7821 -- type itself is frozen, because the class-wide type refers to the 7822 -- tagged type which generates the class. 7823 7824 if Is_Tagged_Type (E) 7825 and then not Is_Class_Wide_Type (E) 7826 and then Present (Class_Wide_Type (E)) 7827 then 7828 Freeze_And_Append (Class_Wide_Type (E), N, Result); 7829 end if; 7830 end if; 7831 7832 Check_Debug_Info_Needed (E); 7833 7834 -- If subprogram has address clause then reset Is_Public flag, since we 7835 -- do not want the backend to generate external references. 7836 7837 if Is_Subprogram (E) 7838 and then Present (Address_Clause (E)) 7839 and then not Is_Library_Level_Entity (E) 7840 then 7841 Set_Is_Public (E, False); 7842 end if; 7843 7844 -- The Ghost mode of the enclosing context is ignored, while the 7845 -- entity being frozen is living. Insert the freezing action prior 7846 -- to the start of the enclosing ignored Ghost region. As a result 7847 -- the freezeing action will be preserved when the ignored Ghost 7848 -- context is eliminated. The insertion must take place even when 7849 -- the context is a spec expression, otherwise "Handling of Default 7850 -- and Per-Object Expressions" will suppress the insertion, and the 7851 -- freeze node will be dropped on the floor. 7852 7853 if Saved_GM = Ignore 7854 and then Ghost_Mode /= Ignore 7855 and then Present (Ignored_Ghost_Region) 7856 then 7857 Insert_Actions 7858 (Assoc_Node => Ignored_Ghost_Region, 7859 Ins_Actions => Result, 7860 Spec_Expr_OK => True); 7861 7862 Result := No_List; 7863 end if; 7864 7865 <<Leave>> 7866 Restore_Ghost_Region (Saved_GM, Saved_IGR); 7867 7868 return Result; 7869 end Freeze_Entity; 7870 7871 ----------------------------- 7872 -- Freeze_Enumeration_Type -- 7873 ----------------------------- 7874 7875 procedure Freeze_Enumeration_Type (Typ : Entity_Id) is 7876 begin 7877 -- By default, if no size clause is present, an enumeration type with 7878 -- Convention C is assumed to interface to a C enum and has integer 7879 -- size, except for a boolean type because it is assumed to interface 7880 -- to _Bool introduced in C99. This applies to types. For subtypes, 7881 -- verify that its base type has no size clause either. Treat other 7882 -- foreign conventions in the same way, and also make sure alignment 7883 -- is set right. 7884 7885 if Has_Foreign_Convention (Typ) 7886 and then not Is_Boolean_Type (Typ) 7887 and then not Has_Size_Clause (Typ) 7888 and then not Has_Size_Clause (Base_Type (Typ)) 7889 and then Esize (Typ) < Standard_Integer_Size 7890 7891 -- Don't do this if Short_Enums on target 7892 7893 and then not Target_Short_Enums 7894 then 7895 Set_Esize (Typ, UI_From_Int (Standard_Integer_Size)); 7896 Set_Alignment (Typ, Alignment (Standard_Integer)); 7897 7898 -- Normal Ada case or size clause present or not Long_C_Enums on target 7899 7900 else 7901 -- If the enumeration type interfaces to C, and it has a size clause 7902 -- that specifies less than int size, it warrants a warning. The 7903 -- user may intend the C type to be an enum or a char, so this is 7904 -- not by itself an error that the Ada compiler can detect, but it 7905 -- it is a worth a heads-up. For Boolean and Character types we 7906 -- assume that the programmer has the proper C type in mind. 7907 7908 if Convention (Typ) = Convention_C 7909 and then Has_Size_Clause (Typ) 7910 and then Esize (Typ) /= Esize (Standard_Integer) 7911 and then not Is_Boolean_Type (Typ) 7912 and then not Is_Character_Type (Typ) 7913 7914 -- Don't do this if Short_Enums on target 7915 7916 and then not Target_Short_Enums 7917 then 7918 Error_Msg_N 7919 ("C enum types have the size of a C int??", Size_Clause (Typ)); 7920 end if; 7921 7922 Adjust_Esize_For_Alignment (Typ); 7923 end if; 7924 end Freeze_Enumeration_Type; 7925 7926 ----------------------- 7927 -- Freeze_Expression -- 7928 ----------------------- 7929 7930 procedure Freeze_Expression (N : Node_Id) is 7931 7932 function Find_Aggregate_Component_Desig_Type return Entity_Id; 7933 -- If the expression is an array aggregate, the type of the component 7934 -- expressions is also frozen. If the component type is an access type 7935 -- and the expressions include allocators, the designed type is frozen 7936 -- as well. 7937 7938 function In_Expanded_Body (N : Node_Id) return Boolean; 7939 -- Given an N_Handled_Sequence_Of_Statements node, determines whether it 7940 -- is the statement sequence of an expander-generated subprogram: body 7941 -- created for an expression function, for a predicate function, an init 7942 -- proc, a stream subprogram, or a renaming as body. If so, this is not 7943 -- a freezing context and the entity will be frozen at a later point. 7944 7945 function Has_Decl_In_List 7946 (E : Entity_Id; 7947 N : Node_Id; 7948 L : List_Id) return Boolean; 7949 -- Determines whether an entity E referenced in node N is declared in 7950 -- the list L. 7951 7952 ----------------------------------------- 7953 -- Find_Aggregate_Component_Desig_Type -- 7954 ----------------------------------------- 7955 7956 function Find_Aggregate_Component_Desig_Type return Entity_Id is 7957 Assoc : Node_Id; 7958 Exp : Node_Id; 7959 7960 begin 7961 if Present (Expressions (N)) then 7962 Exp := First (Expressions (N)); 7963 while Present (Exp) loop 7964 if Nkind (Exp) = N_Allocator then 7965 return Designated_Type (Component_Type (Etype (N))); 7966 end if; 7967 7968 Next (Exp); 7969 end loop; 7970 end if; 7971 7972 if Present (Component_Associations (N)) then 7973 Assoc := First (Component_Associations (N)); 7974 while Present (Assoc) loop 7975 if Nkind (Expression (Assoc)) = N_Allocator then 7976 return Designated_Type (Component_Type (Etype (N))); 7977 end if; 7978 7979 Next (Assoc); 7980 end loop; 7981 end if; 7982 7983 return Empty; 7984 end Find_Aggregate_Component_Desig_Type; 7985 7986 ---------------------- 7987 -- In_Expanded_Body -- 7988 ---------------------- 7989 7990 function In_Expanded_Body (N : Node_Id) return Boolean is 7991 P : constant Node_Id := Parent (N); 7992 Id : Entity_Id; 7993 7994 begin 7995 if Nkind (P) /= N_Subprogram_Body then 7996 return False; 7997 7998 -- AI12-0157: An expression function that is a completion is a freeze 7999 -- point. If the body is the result of expansion, it is not. 8000 8001 elsif Was_Expression_Function (P) then 8002 return not Comes_From_Source (P); 8003 8004 -- This is the body of a generated predicate function 8005 8006 elsif Present (Corresponding_Spec (P)) 8007 and then Is_Predicate_Function (Corresponding_Spec (P)) 8008 then 8009 return True; 8010 8011 else 8012 Id := Defining_Unit_Name (Specification (P)); 8013 8014 -- The following are expander-created bodies, or bodies that 8015 -- are not freeze points. 8016 8017 if Nkind (Id) = N_Defining_Identifier 8018 and then (Is_Init_Proc (Id) 8019 or else Is_TSS (Id, TSS_Stream_Input) 8020 or else Is_TSS (Id, TSS_Stream_Output) 8021 or else Is_TSS (Id, TSS_Stream_Read) 8022 or else Is_TSS (Id, TSS_Stream_Write) 8023 or else Is_TSS (Id, TSS_Put_Image) 8024 or else Nkind (Original_Node (P)) = 8025 N_Subprogram_Renaming_Declaration) 8026 then 8027 return True; 8028 else 8029 return False; 8030 end if; 8031 end if; 8032 end In_Expanded_Body; 8033 8034 ---------------------- 8035 -- Has_Decl_In_List -- 8036 ---------------------- 8037 8038 function Has_Decl_In_List 8039 (E : Entity_Id; 8040 N : Node_Id; 8041 L : List_Id) return Boolean 8042 is 8043 Decl_Node : Node_Id; 8044 8045 begin 8046 -- If E is an itype, pretend that it is declared in N 8047 8048 if Is_Itype (E) then 8049 Decl_Node := N; 8050 else 8051 Decl_Node := Declaration_Node (E); 8052 end if; 8053 8054 return Is_List_Member (Decl_Node) 8055 and then List_Containing (Decl_Node) = L; 8056 end Has_Decl_In_List; 8057 8058 -- Local variables 8059 8060 In_Spec_Exp : constant Boolean := In_Spec_Expression; 8061 8062 Desig_Typ : Entity_Id; 8063 Nam : Entity_Id; 8064 P : Node_Id; 8065 Parent_P : Node_Id; 8066 Typ : Entity_Id; 8067 8068 Allocator_Typ : Entity_Id := Empty; 8069 8070 Freeze_Outside : Boolean := False; 8071 -- This flag is set true if the entity must be frozen outside the 8072 -- current subprogram. This happens in the case of expander generated 8073 -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do 8074 -- not freeze all entities like other bodies, but which nevertheless 8075 -- may reference entities that have to be frozen before the body and 8076 -- obviously cannot be frozen inside the body. 8077 8078 Freeze_Outside_Subp : Entity_Id := Empty; 8079 -- This entity is set if we are inside a subprogram body and the frozen 8080 -- entity is defined in the enclosing scope of this subprogram. In such 8081 -- case we must skip the subprogram body when climbing the parents chain 8082 -- to locate the correct placement for the freezing node. 8083 8084 -- Start of processing for Freeze_Expression 8085 8086 begin 8087 -- Immediate return if freezing is inhibited. This flag is set by the 8088 -- analyzer to stop freezing on generated expressions that would cause 8089 -- freezing if they were in the source program, but which are not 8090 -- supposed to freeze, since they are created. 8091 8092 if Must_Not_Freeze (N) then 8093 return; 8094 end if; 8095 8096 -- If expression is non-static, then it does not freeze in a default 8097 -- expression, see section "Handling of Default Expressions" in the 8098 -- spec of package Sem for further details. Note that we have to make 8099 -- sure that we actually have a real expression (if we have a subtype 8100 -- indication, we can't test Is_OK_Static_Expression). However, we 8101 -- exclude the case of the prefix of an attribute of a static scalar 8102 -- subtype from this early return, because static subtype attributes 8103 -- should always cause freezing, even in default expressions, but 8104 -- the attribute may not have been marked as static yet (because in 8105 -- Resolve_Attribute, the call to Eval_Attribute follows the call of 8106 -- Freeze_Expression on the prefix). 8107 8108 if In_Spec_Exp 8109 and then Nkind (N) in N_Subexpr 8110 and then not Is_OK_Static_Expression (N) 8111 and then (Nkind (Parent (N)) /= N_Attribute_Reference 8112 or else not (Is_Entity_Name (N) 8113 and then Is_Type (Entity (N)) 8114 and then Is_OK_Static_Subtype (Entity (N)))) 8115 then 8116 return; 8117 end if; 8118 8119 -- Freeze type of expression if not frozen already 8120 8121 Typ := Empty; 8122 8123 if Nkind (N) in N_Has_Etype and then Present (Etype (N)) then 8124 if not Is_Frozen (Etype (N)) then 8125 Typ := Etype (N); 8126 8127 -- Base type may be an derived numeric type that is frozen at the 8128 -- point of declaration, but first_subtype is still unfrozen. 8129 8130 elsif not Is_Frozen (First_Subtype (Etype (N))) then 8131 Typ := First_Subtype (Etype (N)); 8132 end if; 8133 end if; 8134 8135 -- For entity name, freeze entity if not frozen already. A special 8136 -- exception occurs for an identifier that did not come from source. 8137 -- We don't let such identifiers freeze a non-internal entity, i.e. 8138 -- an entity that did come from source, since such an identifier was 8139 -- generated by the expander, and cannot have any semantic effect on 8140 -- the freezing semantics. For example, this stops the parameter of 8141 -- an initialization procedure from freezing the variable. 8142 8143 if Is_Entity_Name (N) 8144 and then Present (Entity (N)) 8145 and then not Is_Frozen (Entity (N)) 8146 and then (Nkind (N) /= N_Identifier 8147 or else Comes_From_Source (N) 8148 or else not Comes_From_Source (Entity (N))) 8149 then 8150 Nam := Entity (N); 8151 8152 if Present (Nam) and then Ekind (Nam) = E_Function then 8153 Check_Expression_Function (N, Nam); 8154 end if; 8155 8156 else 8157 Nam := Empty; 8158 end if; 8159 8160 -- For an allocator freeze designated type if not frozen already 8161 8162 -- For an aggregate whose component type is an access type, freeze the 8163 -- designated type now, so that its freeze does not appear within the 8164 -- loop that might be created in the expansion of the aggregate. If the 8165 -- designated type is a private type without full view, the expression 8166 -- cannot contain an allocator, so the type is not frozen. 8167 8168 -- For a function, we freeze the entity when the subprogram declaration 8169 -- is frozen, but a function call may appear in an initialization proc. 8170 -- before the declaration is frozen. We need to generate the extra 8171 -- formals, if any, to ensure that the expansion of the call includes 8172 -- the proper actuals. This only applies to Ada subprograms, not to 8173 -- imported ones. 8174 8175 Desig_Typ := Empty; 8176 8177 case Nkind (N) is 8178 when N_Allocator => 8179 Desig_Typ := Designated_Type (Etype (N)); 8180 8181 if Nkind (Expression (N)) = N_Qualified_Expression then 8182 Allocator_Typ := Entity (Subtype_Mark (Expression (N))); 8183 end if; 8184 8185 when N_Aggregate => 8186 if Is_Array_Type (Etype (N)) 8187 and then Is_Access_Type (Component_Type (Etype (N))) 8188 then 8189 -- Check whether aggregate includes allocators 8190 8191 Desig_Typ := Find_Aggregate_Component_Desig_Type; 8192 end if; 8193 8194 when N_Indexed_Component 8195 | N_Selected_Component 8196 | N_Slice 8197 => 8198 if Is_Access_Type (Etype (Prefix (N))) then 8199 Desig_Typ := Designated_Type (Etype (Prefix (N))); 8200 end if; 8201 8202 when N_Identifier => 8203 if Present (Nam) 8204 and then Ekind (Nam) = E_Function 8205 and then Nkind (Parent (N)) = N_Function_Call 8206 and then Convention (Nam) = Convention_Ada 8207 then 8208 Create_Extra_Formals (Nam); 8209 end if; 8210 8211 when others => 8212 null; 8213 end case; 8214 8215 if Desig_Typ /= Empty 8216 and then (Is_Frozen (Desig_Typ) 8217 or else (not Is_Fully_Defined (Desig_Typ))) 8218 then 8219 Desig_Typ := Empty; 8220 end if; 8221 8222 -- All done if nothing needs freezing 8223 8224 if No (Typ) 8225 and then No (Nam) 8226 and then No (Desig_Typ) 8227 and then No (Allocator_Typ) 8228 then 8229 return; 8230 end if; 8231 8232 -- Check if we are inside a subprogram body and the frozen entity is 8233 -- defined in the enclosing scope of this subprogram. In such case we 8234 -- must skip the subprogram when climbing the parents chain to locate 8235 -- the correct placement for the freezing node. 8236 8237 -- This is not needed for default expressions and other spec expressions 8238 -- in generic units since the Move_Freeze_Nodes mechanism (sem_ch12.adb) 8239 -- takes care of placing them at the proper place, after the generic 8240 -- unit. 8241 8242 if Present (Nam) 8243 and then Scope (Nam) /= Current_Scope 8244 and then not (In_Spec_Exp and then Inside_A_Generic) 8245 then 8246 declare 8247 S : Entity_Id := Current_Scope; 8248 8249 begin 8250 while Present (S) 8251 and then In_Same_Source_Unit (Nam, S) 8252 loop 8253 if Scope (S) = Scope (Nam) then 8254 if Is_Subprogram (S) and then Has_Completion (S) then 8255 Freeze_Outside_Subp := S; 8256 end if; 8257 8258 exit; 8259 end if; 8260 8261 S := Scope (S); 8262 end loop; 8263 end; 8264 end if; 8265 8266 -- Examine the enclosing context by climbing the parent chain 8267 8268 -- If we identified that we must freeze the entity outside of a given 8269 -- subprogram then we just climb up to that subprogram checking if some 8270 -- enclosing node is marked as Must_Not_Freeze (since in such case we 8271 -- must not freeze yet this entity). 8272 8273 P := N; 8274 8275 if Present (Freeze_Outside_Subp) then 8276 loop 8277 -- Do not freeze the current expression if another expression in 8278 -- the chain of parents must not be frozen. 8279 8280 if Nkind (P) in N_Subexpr and then Must_Not_Freeze (P) then 8281 return; 8282 end if; 8283 8284 Parent_P := Parent (P); 8285 8286 -- If we don't have a parent, then we are not in a well-formed 8287 -- tree. This is an unusual case, but there are some legitimate 8288 -- situations in which this occurs, notably when the expressions 8289 -- in the range of a type declaration are resolved. We simply 8290 -- ignore the freeze request in this case. 8291 8292 if No (Parent_P) then 8293 return; 8294 end if; 8295 8296 -- If the parent is a subprogram body, the candidate insertion 8297 -- point is just ahead of it. 8298 8299 if Nkind (Parent_P) = N_Subprogram_Body 8300 and then Unique_Defining_Entity (Parent_P) = 8301 Freeze_Outside_Subp 8302 then 8303 P := Parent_P; 8304 exit; 8305 end if; 8306 8307 P := Parent_P; 8308 end loop; 8309 8310 -- Otherwise the traversal serves two purposes - to detect scenarios 8311 -- where freezeing is not needed and to find the proper insertion point 8312 -- for the freeze nodes. Although somewhat similar to Insert_Actions, 8313 -- this traversal is freezing semantics-sensitive. Inserting freeze 8314 -- nodes blindly in the tree may result in types being frozen too early. 8315 8316 else 8317 loop 8318 -- Do not freeze the current expression if another expression in 8319 -- the chain of parents must not be frozen. 8320 8321 if Nkind (P) in N_Subexpr and then Must_Not_Freeze (P) then 8322 return; 8323 end if; 8324 8325 Parent_P := Parent (P); 8326 8327 -- If we don't have a parent, then we are not in a well-formed 8328 -- tree. This is an unusual case, but there are some legitimate 8329 -- situations in which this occurs, notably when the expressions 8330 -- in the range of a type declaration are resolved. We simply 8331 -- ignore the freeze request in this case. 8332 8333 if No (Parent_P) then 8334 return; 8335 end if; 8336 8337 -- See if we have got to an appropriate point in the tree 8338 8339 case Nkind (Parent_P) is 8340 8341 -- A special test for the exception of (RM 13.14(8)) for the 8342 -- case of per-object expressions (RM 3.8(18)) occurring in 8343 -- component definition or a discrete subtype definition. Note 8344 -- that we test for a component declaration which includes both 8345 -- cases we are interested in, and furthermore the tree does 8346 -- not have explicit nodes for either of these two constructs. 8347 8348 when N_Component_Declaration => 8349 8350 -- The case we want to test for here is an identifier that 8351 -- is a per-object expression, this is either a discriminant 8352 -- that appears in a context other than the component 8353 -- declaration or it is a reference to the type of the 8354 -- enclosing construct. 8355 8356 -- For either of these cases, we skip the freezing 8357 8358 if not In_Spec_Expression 8359 and then Nkind (N) = N_Identifier 8360 and then (Present (Entity (N))) 8361 then 8362 -- We recognize the discriminant case by just looking for 8363 -- a reference to a discriminant. It can only be one for 8364 -- the enclosing construct. Skip freezing in this case. 8365 8366 if Ekind (Entity (N)) = E_Discriminant then 8367 return; 8368 8369 -- For the case of a reference to the enclosing record, 8370 -- (or task or protected type), we look for a type that 8371 -- matches the current scope. 8372 8373 elsif Entity (N) = Current_Scope then 8374 return; 8375 end if; 8376 end if; 8377 8378 -- If we have an enumeration literal that appears as the choice 8379 -- in the aggregate of an enumeration representation clause, 8380 -- then freezing does not occur (RM 13.14(10)). 8381 8382 when N_Enumeration_Representation_Clause => 8383 8384 -- The case we are looking for is an enumeration literal 8385 8386 if Nkind (N) in N_Identifier | N_Character_Literal 8387 and then Is_Enumeration_Type (Etype (N)) 8388 then 8389 -- If enumeration literal appears directly as the choice, 8390 -- do not freeze (this is the normal non-overloaded case) 8391 8392 if Nkind (Parent (N)) = N_Component_Association 8393 and then First (Choices (Parent (N))) = N 8394 then 8395 return; 8396 8397 -- If enumeration literal appears as the name of function 8398 -- which is the choice, then also do not freeze. This 8399 -- happens in the overloaded literal case, where the 8400 -- enumeration literal is temporarily changed to a 8401 -- function call for overloading analysis purposes. 8402 8403 elsif Nkind (Parent (N)) = N_Function_Call 8404 and then Nkind (Parent (Parent (N))) = 8405 N_Component_Association 8406 and then First (Choices (Parent (Parent (N)))) = 8407 Parent (N) 8408 then 8409 return; 8410 end if; 8411 end if; 8412 8413 -- Normally if the parent is a handled sequence of statements, 8414 -- then the current node must be a statement, and that is an 8415 -- appropriate place to insert a freeze node. 8416 8417 when N_Handled_Sequence_Of_Statements => 8418 8419 -- An exception occurs when the sequence of statements is 8420 -- for an expander generated body that did not do the usual 8421 -- freeze all operation. In this case we usually want to 8422 -- freeze outside this body, not inside it, and we skip 8423 -- past the subprogram body that we are inside. 8424 8425 if In_Expanded_Body (Parent_P) then 8426 declare 8427 Subp_Body : constant Node_Id := Parent (Parent_P); 8428 Spec_Id : Entity_Id; 8429 8430 begin 8431 -- Freeze the entity only when it is declared inside 8432 -- the body of the expander generated procedure. This 8433 -- case is recognized by the subprogram scope of the 8434 -- entity or its type, which is either the spec of an 8435 -- enclosing body, or (in the case of init_procs for 8436 -- which there is no separate spec) the current scope. 8437 8438 if Nkind (Subp_Body) = N_Subprogram_Body then 8439 declare 8440 S : Entity_Id; 8441 8442 begin 8443 Spec_Id := Corresponding_Spec (Subp_Body); 8444 8445 if Present (Typ) then 8446 S := Scope (Typ); 8447 elsif Present (Nam) then 8448 S := Scope (Nam); 8449 else 8450 S := Standard_Standard; 8451 end if; 8452 8453 while S /= Standard_Standard 8454 and then not Is_Subprogram (S) 8455 loop 8456 S := Scope (S); 8457 end loop; 8458 8459 if S = Spec_Id then 8460 exit; 8461 8462 elsif Present (Typ) 8463 and then Scope (Typ) = Current_Scope 8464 and then 8465 Defining_Entity (Subp_Body) = Current_Scope 8466 then 8467 exit; 8468 end if; 8469 end; 8470 end if; 8471 8472 -- If the entity is not frozen by an expression 8473 -- function that is not a completion, continue 8474 -- climbing the tree. 8475 8476 if Nkind (Subp_Body) = N_Subprogram_Body 8477 and then Was_Expression_Function (Subp_Body) 8478 then 8479 null; 8480 8481 -- Freeze outside the body 8482 8483 else 8484 Parent_P := Parent (Parent_P); 8485 Freeze_Outside := True; 8486 end if; 8487 end; 8488 8489 -- Here if normal case where we are in handled statement 8490 -- sequence and want to do the insertion right there. 8491 8492 else 8493 exit; 8494 end if; 8495 8496 -- If parent is a body or a spec or a block, then the current 8497 -- node is a statement or declaration and we can insert the 8498 -- freeze node before it. 8499 8500 when N_Block_Statement 8501 | N_Entry_Body 8502 | N_Package_Body 8503 | N_Package_Specification 8504 | N_Protected_Body 8505 | N_Subprogram_Body 8506 | N_Task_Body 8507 => 8508 exit; 8509 8510 -- The expander is allowed to define types in any statements 8511 -- list, so any of the following parent nodes also mark a 8512 -- freezing point if the actual node is in a list of 8513 -- statements or declarations. 8514 8515 when N_Abortable_Part 8516 | N_Accept_Alternative 8517 | N_Case_Statement_Alternative 8518 | N_Compilation_Unit_Aux 8519 | N_Conditional_Entry_Call 8520 | N_Delay_Alternative 8521 | N_Elsif_Part 8522 | N_Entry_Call_Alternative 8523 | N_Exception_Handler 8524 | N_Extended_Return_Statement 8525 | N_Freeze_Entity 8526 | N_If_Statement 8527 | N_Selective_Accept 8528 | N_Triggering_Alternative 8529 => 8530 exit when Is_List_Member (P); 8531 8532 -- The freeze nodes produced by an expression coming from the 8533 -- Actions list of an N_Expression_With_Actions, short-circuit 8534 -- expression or N_Case_Expression_Alternative node must remain 8535 -- within the Actions list if they freeze an entity declared in 8536 -- this list, as inserting the freeze nodes further up the tree 8537 -- may lead to use before declaration issues for the entity. 8538 8539 when N_Case_Expression_Alternative 8540 | N_Expression_With_Actions 8541 | N_Short_Circuit 8542 => 8543 exit when (Present (Nam) 8544 and then 8545 Has_Decl_In_List (Nam, P, Actions (Parent_P))) 8546 or else (Present (Typ) 8547 and then 8548 Has_Decl_In_List (Typ, P, Actions (Parent_P))); 8549 8550 -- Likewise for an N_If_Expression and its two Actions list 8551 8552 when N_If_Expression => 8553 declare 8554 L1 : constant List_Id := Then_Actions (Parent_P); 8555 L2 : constant List_Id := Else_Actions (Parent_P); 8556 8557 begin 8558 exit when (Present (Nam) 8559 and then 8560 Has_Decl_In_List (Nam, P, L1)) 8561 or else (Present (Typ) 8562 and then 8563 Has_Decl_In_List (Typ, P, L1)) 8564 or else (Present (Nam) 8565 and then 8566 Has_Decl_In_List (Nam, P, L2)) 8567 or else (Present (Typ) 8568 and then 8569 Has_Decl_In_List (Typ, P, L2)); 8570 end; 8571 8572 -- N_Loop_Statement is a special case: a type that appears in 8573 -- the source can never be frozen in a loop (this occurs only 8574 -- because of a loop expanded by the expander), so we keep on 8575 -- going. Otherwise we terminate the search. Same is true of 8576 -- any entity which comes from source (if it has a predefined 8577 -- type, this type does not appear to come from source, but the 8578 -- entity should not be frozen here). 8579 8580 when N_Loop_Statement => 8581 exit when not Comes_From_Source (Etype (N)) 8582 and then (No (Nam) or else not Comes_From_Source (Nam)); 8583 8584 -- For all other cases, keep looking at parents 8585 8586 when others => 8587 null; 8588 end case; 8589 8590 -- We fall through the case if we did not yet find the proper 8591 -- place in the tree for inserting the freeze node, so climb. 8592 8593 P := Parent_P; 8594 end loop; 8595 end if; 8596 8597 -- If the expression appears in a record or an initialization procedure, 8598 -- the freeze nodes are collected and attached to the current scope, to 8599 -- be inserted and analyzed on exit from the scope, to insure that 8600 -- generated entities appear in the correct scope. If the expression is 8601 -- a default for a discriminant specification, the scope is still void. 8602 -- The expression can also appear in the discriminant part of a private 8603 -- or concurrent type. 8604 8605 -- If the expression appears in a constrained subcomponent of an 8606 -- enclosing record declaration, the freeze nodes must be attached to 8607 -- the outer record type so they can eventually be placed in the 8608 -- enclosing declaration list. 8609 8610 -- The other case requiring this special handling is if we are in a 8611 -- default expression, since in that case we are about to freeze a 8612 -- static type, and the freeze scope needs to be the outer scope, not 8613 -- the scope of the subprogram with the default parameter. 8614 8615 -- For default expressions and other spec expressions in generic units, 8616 -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of 8617 -- placing them at the proper place, after the generic unit. 8618 8619 if (In_Spec_Exp and not Inside_A_Generic) 8620 or else Freeze_Outside 8621 or else (Is_Type (Current_Scope) 8622 and then (not Is_Concurrent_Type (Current_Scope) 8623 or else not Has_Completion (Current_Scope))) 8624 or else Ekind (Current_Scope) = E_Void 8625 then 8626 declare 8627 Freeze_Nodes : List_Id := No_List; 8628 Pos : Int := Scope_Stack.Last; 8629 8630 begin 8631 if Present (Desig_Typ) then 8632 Freeze_And_Append (Desig_Typ, N, Freeze_Nodes); 8633 end if; 8634 8635 if Present (Typ) then 8636 Freeze_And_Append (Typ, N, Freeze_Nodes); 8637 end if; 8638 8639 if Present (Nam) then 8640 Freeze_And_Append (Nam, N, Freeze_Nodes); 8641 end if; 8642 8643 -- The current scope may be that of a constrained component of 8644 -- an enclosing record declaration, or of a loop of an enclosing 8645 -- quantified expression, which is above the current scope in the 8646 -- scope stack. Indeed in the context of a quantified expression, 8647 -- a scope is created and pushed above the current scope in order 8648 -- to emulate the loop-like behavior of the quantified expression. 8649 -- If the expression is within a top-level pragma, as for a pre- 8650 -- condition on a library-level subprogram, nothing to do. 8651 8652 if not Is_Compilation_Unit (Current_Scope) 8653 and then (Is_Record_Type (Scope (Current_Scope)) 8654 or else Nkind (Parent (Current_Scope)) = 8655 N_Quantified_Expression) 8656 then 8657 Pos := Pos - 1; 8658 end if; 8659 8660 if Is_Non_Empty_List (Freeze_Nodes) then 8661 8662 -- When the current scope is transient, insert the freeze nodes 8663 -- prior to the expression that produced them. Transient scopes 8664 -- may create additional declarations when finalizing objects 8665 -- or managing the secondary stack. Inserting the freeze nodes 8666 -- of those constructs prior to the scope would result in a 8667 -- freeze-before-declaration, therefore the freeze node must 8668 -- remain interleaved with their constructs. 8669 8670 if Scope_Is_Transient then 8671 Insert_Actions (N, Freeze_Nodes); 8672 8673 elsif No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then 8674 Scope_Stack.Table (Pos).Pending_Freeze_Actions := 8675 Freeze_Nodes; 8676 else 8677 Append_List (Freeze_Nodes, 8678 Scope_Stack.Table (Pos).Pending_Freeze_Actions); 8679 end if; 8680 end if; 8681 end; 8682 8683 return; 8684 end if; 8685 8686 -- Now we have the right place to do the freezing. First, a special 8687 -- adjustment, if we are in spec-expression analysis mode, these freeze 8688 -- actions must not be thrown away (normally all inserted actions are 8689 -- thrown away in this mode. However, the freeze actions are from static 8690 -- expressions and one of the important reasons we are doing this 8691 -- special analysis is to get these freeze actions. Therefore we turn 8692 -- off the In_Spec_Expression mode to propagate these freeze actions. 8693 -- This also means they get properly analyzed and expanded. 8694 8695 In_Spec_Expression := False; 8696 8697 -- Freeze the subtype mark before a qualified expression on an 8698 -- allocator as per AARM 13.14(4.a). This is needed in particular to 8699 -- generate predicate functions. 8700 8701 if Present (Allocator_Typ) then 8702 Freeze_Before (P, Allocator_Typ); 8703 end if; 8704 8705 -- Freeze the designated type of an allocator (RM 13.14(13)) 8706 8707 if Present (Desig_Typ) then 8708 Freeze_Before (P, Desig_Typ); 8709 end if; 8710 8711 -- Freeze type of expression (RM 13.14(10)). Note that we took care of 8712 -- the enumeration representation clause exception in the loop above. 8713 8714 if Present (Typ) then 8715 Freeze_Before (P, Typ); 8716 end if; 8717 8718 -- Freeze name if one is present (RM 13.14(11)) 8719 8720 if Present (Nam) then 8721 Freeze_Before (P, Nam); 8722 end if; 8723 8724 -- Restore In_Spec_Expression flag 8725 8726 In_Spec_Expression := In_Spec_Exp; 8727 end Freeze_Expression; 8728 8729 ----------------------- 8730 -- Freeze_Expr_Types -- 8731 ----------------------- 8732 8733 procedure Freeze_Expr_Types 8734 (Def_Id : Entity_Id; 8735 Typ : Entity_Id; 8736 Expr : Node_Id; 8737 N : Node_Id) 8738 is 8739 function Cloned_Expression return Node_Id; 8740 -- Build a duplicate of the expression of the return statement that has 8741 -- no defining entities shared with the original expression. 8742 8743 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result; 8744 -- Freeze all types referenced in the subtree rooted at Node 8745 8746 ----------------------- 8747 -- Cloned_Expression -- 8748 ----------------------- 8749 8750 function Cloned_Expression return Node_Id is 8751 function Clone_Id (Node : Node_Id) return Traverse_Result; 8752 -- Tree traversal routine that clones the defining identifier of 8753 -- iterator and loop parameter specification nodes. 8754 8755 -------------- 8756 -- Clone_Id -- 8757 -------------- 8758 8759 function Clone_Id (Node : Node_Id) return Traverse_Result is 8760 begin 8761 if Nkind (Node) in 8762 N_Iterator_Specification | N_Loop_Parameter_Specification 8763 then 8764 Set_Defining_Identifier 8765 (Node, New_Copy (Defining_Identifier (Node))); 8766 end if; 8767 8768 return OK; 8769 end Clone_Id; 8770 8771 procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id); 8772 8773 -- Local variable 8774 8775 Dup_Expr : constant Node_Id := New_Copy_Tree (Expr); 8776 8777 -- Start of processing for Cloned_Expression 8778 8779 begin 8780 -- We must duplicate the expression with semantic information to 8781 -- inherit the decoration of global entities in generic instances. 8782 -- Set the parent of the new node to be the parent of the original 8783 -- to get the proper context, which is needed for complete error 8784 -- reporting and for semantic analysis. 8785 8786 Set_Parent (Dup_Expr, Parent (Expr)); 8787 8788 -- Replace the defining identifier of iterators and loop param 8789 -- specifications by a clone to ensure that the cloned expression 8790 -- and the original expression don't have shared identifiers; 8791 -- otherwise, as part of the preanalysis of the expression, these 8792 -- shared identifiers may be left decorated with itypes which 8793 -- will not be available in the tree passed to the backend. 8794 8795 Clone_Def_Ids (Dup_Expr); 8796 8797 return Dup_Expr; 8798 end Cloned_Expression; 8799 8800 ---------------------- 8801 -- Freeze_Type_Refs -- 8802 ---------------------- 8803 8804 function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is 8805 procedure Check_And_Freeze_Type (Typ : Entity_Id); 8806 -- Check that Typ is fully declared and freeze it if so 8807 8808 --------------------------- 8809 -- Check_And_Freeze_Type -- 8810 --------------------------- 8811 8812 procedure Check_And_Freeze_Type (Typ : Entity_Id) is 8813 begin 8814 -- Skip Itypes created by the preanalysis, and itypes whose 8815 -- scope is another type (i.e. component subtypes that depend 8816 -- on a discriminant), 8817 8818 if Is_Itype (Typ) 8819 and then (Scope_Within_Or_Same (Scope (Typ), Def_Id) 8820 or else Is_Type (Scope (Typ))) 8821 then 8822 return; 8823 end if; 8824 8825 -- This provides a better error message than generating primitives 8826 -- whose compilation fails much later. Refine the error message if 8827 -- possible. 8828 8829 Check_Fully_Declared (Typ, Node); 8830 8831 if Error_Posted (Node) then 8832 if Has_Private_Component (Typ) 8833 and then not Is_Private_Type (Typ) 8834 then 8835 Error_Msg_NE ("\type& has private component", Node, Typ); 8836 end if; 8837 8838 else 8839 Freeze_Before (N, Typ); 8840 end if; 8841 end Check_And_Freeze_Type; 8842 8843 -- Start of processing for Freeze_Type_Refs 8844 8845 begin 8846 -- Check that a type referenced by an entity can be frozen 8847 8848 if Is_Entity_Name (Node) and then Present (Entity (Node)) then 8849 -- The entity itself may be a type, as in a membership test 8850 -- or an attribute reference. Freezing its own type would be 8851 -- incomplete if the entity is derived or an extension. 8852 8853 if Is_Type (Entity (Node)) then 8854 Check_And_Freeze_Type (Entity (Node)); 8855 8856 else 8857 Check_And_Freeze_Type (Etype (Entity (Node))); 8858 end if; 8859 8860 -- Check that the enclosing record type can be frozen 8861 8862 if Ekind (Entity (Node)) in E_Component | E_Discriminant then 8863 Check_And_Freeze_Type (Scope (Entity (Node))); 8864 end if; 8865 8866 -- Freezing an access type does not freeze the designated type, but 8867 -- freezing conversions between access to interfaces requires that 8868 -- the interface types themselves be frozen, so that dispatch table 8869 -- entities are properly created. 8870 8871 -- Unclear whether a more general rule is needed ??? 8872 8873 elsif Nkind (Node) = N_Type_Conversion 8874 and then Is_Access_Type (Etype (Node)) 8875 and then Is_Interface (Designated_Type (Etype (Node))) 8876 then 8877 Check_And_Freeze_Type (Designated_Type (Etype (Node))); 8878 end if; 8879 8880 -- An implicit dereference freezes the designated type. In the case 8881 -- of a dispatching call whose controlling argument is an access 8882 -- type, the dereference is not made explicit, so we must check for 8883 -- such a call and freeze the designated type. 8884 8885 if Nkind (Node) in N_Has_Etype 8886 and then Present (Etype (Node)) 8887 and then Is_Access_Type (Etype (Node)) 8888 then 8889 if Nkind (Parent (Node)) = N_Function_Call 8890 and then Node = Controlling_Argument (Parent (Node)) 8891 then 8892 Check_And_Freeze_Type (Designated_Type (Etype (Node))); 8893 8894 -- An explicit dereference freezes the designated type as well, 8895 -- even though that type is not attached to an entity in the 8896 -- expression. 8897 8898 elsif Nkind (Parent (Node)) = N_Explicit_Dereference then 8899 Check_And_Freeze_Type (Designated_Type (Etype (Node))); 8900 end if; 8901 8902 -- An iterator specification freezes the iterator type, even though 8903 -- that type is not attached to an entity in the construct. 8904 8905 elsif Nkind (Node) in N_Has_Etype 8906 and then Nkind (Parent (Node)) = N_Iterator_Specification 8907 and then Node = Name (Parent (Node)) 8908 then 8909 declare 8910 Iter : constant Node_Id := 8911 Find_Value_Of_Aspect (Etype (Node), Aspect_Default_Iterator); 8912 8913 begin 8914 if Present (Iter) then 8915 Check_And_Freeze_Type (Etype (Iter)); 8916 end if; 8917 end; 8918 end if; 8919 8920 -- No point in posting several errors on the same expression 8921 8922 if Serious_Errors_Detected > 0 then 8923 return Abandon; 8924 else 8925 return OK; 8926 end if; 8927 end Freeze_Type_Refs; 8928 8929 procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs); 8930 8931 -- Local variables 8932 8933 Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id); 8934 Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id); 8935 Dup_Expr : constant Node_Id := Cloned_Expression; 8936 8937 -- Start of processing for Freeze_Expr_Types 8938 8939 begin 8940 -- Preanalyze a duplicate of the expression to have available the 8941 -- minimum decoration needed to locate referenced unfrozen types 8942 -- without adding any decoration to the function expression. 8943 8944 -- This routine is also applied to expressions in the contract for 8945 -- the subprogram. If that happens when expanding the code for 8946 -- pre/postconditions during expansion of the subprogram body, the 8947 -- subprogram is already installed. 8948 8949 if Def_Id /= Current_Scope then 8950 Push_Scope (Def_Id); 8951 Install_Formals (Def_Id); 8952 8953 Preanalyze_Spec_Expression (Dup_Expr, Typ); 8954 End_Scope; 8955 else 8956 Preanalyze_Spec_Expression (Dup_Expr, Typ); 8957 end if; 8958 8959 -- Restore certain attributes of Def_Id since the preanalysis may 8960 -- have introduced itypes to this scope, thus modifying attributes 8961 -- First_Entity and Last_Entity. 8962 8963 Set_First_Entity (Def_Id, Saved_First_Entity); 8964 Set_Last_Entity (Def_Id, Saved_Last_Entity); 8965 8966 if Present (Last_Entity (Def_Id)) then 8967 Set_Next_Entity (Last_Entity (Def_Id), Empty); 8968 end if; 8969 8970 -- Freeze all types referenced in the expression 8971 8972 Freeze_References (Dup_Expr); 8973 end Freeze_Expr_Types; 8974 8975 ----------------------------- 8976 -- Freeze_Fixed_Point_Type -- 8977 ----------------------------- 8978 8979 -- Certain fixed-point types and subtypes, including implicit base types 8980 -- and declared first subtypes, have not yet set up a range. This is 8981 -- because the range cannot be set until the Small and Size values are 8982 -- known, and these are not known till the type is frozen. 8983 8984 -- To signal this case, Scalar_Range contains an unanalyzed syntactic range 8985 -- whose bounds are unanalyzed real literals. This routine will recognize 8986 -- this case, and transform this range node into a properly typed range 8987 -- with properly analyzed and resolved values. 8988 8989 procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is 8990 Rng : constant Node_Id := Scalar_Range (Typ); 8991 Lo : constant Node_Id := Low_Bound (Rng); 8992 Hi : constant Node_Id := High_Bound (Rng); 8993 Btyp : constant Entity_Id := Base_Type (Typ); 8994 Brng : constant Node_Id := Scalar_Range (Btyp); 8995 BLo : constant Node_Id := Low_Bound (Brng); 8996 BHi : constant Node_Id := High_Bound (Brng); 8997 Ftyp : constant Entity_Id := Underlying_Type (First_Subtype (Typ)); 8998 8999 Small : Ureal; 9000 Loval : Ureal; 9001 Hival : Ureal; 9002 Atype : Entity_Id; 9003 9004 Orig_Lo : Ureal; 9005 Orig_Hi : Ureal; 9006 -- Save original bounds (for shaving tests) 9007 9008 Actual_Size : Int; 9009 -- Actual size chosen 9010 9011 function Fsize (Lov, Hiv : Ureal) return Int; 9012 -- Returns size of type with given bounds. Also leaves these 9013 -- bounds set as the current bounds of the Typ. 9014 9015 function Larger (A, B : Ureal) return Boolean; 9016 -- Returns true if A > B with a margin of Typ'Small 9017 9018 function Smaller (A, B : Ureal) return Boolean; 9019 -- Returns true if A < B with a margin of Typ'Small 9020 9021 ----------- 9022 -- Fsize -- 9023 ----------- 9024 9025 function Fsize (Lov, Hiv : Ureal) return Int is 9026 begin 9027 Set_Realval (Lo, Lov); 9028 Set_Realval (Hi, Hiv); 9029 return Minimum_Size (Typ); 9030 end Fsize; 9031 9032 ------------ 9033 -- Larger -- 9034 ------------ 9035 9036 function Larger (A, B : Ureal) return Boolean is 9037 begin 9038 return A > B and then A - Small_Value (Typ) > B; 9039 end Larger; 9040 9041 ------------- 9042 -- Smaller -- 9043 ------------- 9044 9045 function Smaller (A, B : Ureal) return Boolean is 9046 begin 9047 return A < B and then A + Small_Value (Typ) < B; 9048 end Smaller; 9049 9050 -- Start of processing for Freeze_Fixed_Point_Type 9051 9052 begin 9053 -- The type, or its first subtype if we are freezing the anonymous 9054 -- base, may have a delayed Small aspect. It must be analyzed now, 9055 -- so that all characteristics of the type (size, bounds) can be 9056 -- computed and validated in the call to Minimum_Size that follows. 9057 9058 if Has_Delayed_Aspects (Ftyp) then 9059 Analyze_Aspects_At_Freeze_Point (Ftyp); 9060 Set_Has_Delayed_Aspects (Ftyp, False); 9061 end if; 9062 9063 -- Inherit the Small value from the first subtype in any case 9064 9065 if Typ /= Ftyp then 9066 Set_Small_Value (Typ, Small_Value (Ftyp)); 9067 end if; 9068 9069 -- If Esize of a subtype has not previously been set, set it now 9070 9071 if not Known_Esize (Typ) then 9072 Atype := Ancestor_Subtype (Typ); 9073 9074 if Present (Atype) then 9075 Set_Esize (Typ, Esize (Atype)); 9076 else 9077 Copy_Esize (To => Typ, From => Btyp); 9078 end if; 9079 end if; 9080 9081 -- Immediate return if the range is already analyzed. This means that 9082 -- the range is already set, and does not need to be computed by this 9083 -- routine. 9084 9085 if Analyzed (Rng) then 9086 return; 9087 end if; 9088 9089 -- Immediate return if either of the bounds raises Constraint_Error 9090 9091 if Raises_Constraint_Error (Lo) 9092 or else Raises_Constraint_Error (Hi) 9093 then 9094 return; 9095 end if; 9096 9097 Small := Small_Value (Typ); 9098 Loval := Realval (Lo); 9099 Hival := Realval (Hi); 9100 9101 Orig_Lo := Loval; 9102 Orig_Hi := Hival; 9103 9104 -- Ordinary fixed-point case 9105 9106 if Is_Ordinary_Fixed_Point_Type (Typ) then 9107 9108 -- For the ordinary fixed-point case, we are allowed to fudge the 9109 -- end-points up or down by small. Generally we prefer to fudge up, 9110 -- i.e. widen the bounds for non-model numbers so that the end points 9111 -- are included. However there are cases in which this cannot be 9112 -- done, and indeed cases in which we may need to narrow the bounds. 9113 -- The following circuit makes the decision. 9114 9115 -- Note: our terminology here is that Incl_EP means that the bounds 9116 -- are widened by Small if necessary to include the end points, and 9117 -- Excl_EP means that the bounds are narrowed by Small to exclude the 9118 -- end-points if this reduces the size. 9119 9120 -- Note that in the Incl case, all we care about is including the 9121 -- end-points. In the Excl case, we want to narrow the bounds as 9122 -- much as permitted by the RM, to give the smallest possible size. 9123 9124 Fudge : declare 9125 Loval_Incl_EP : Ureal; 9126 Hival_Incl_EP : Ureal; 9127 9128 Loval_Excl_EP : Ureal; 9129 Hival_Excl_EP : Ureal; 9130 9131 Size_Incl_EP : Int; 9132 Size_Excl_EP : Int; 9133 9134 Model_Num : Ureal; 9135 Actual_Lo : Ureal; 9136 Actual_Hi : Ureal; 9137 9138 begin 9139 -- First step. Base types are required to be symmetrical. Right 9140 -- now, the base type range is a copy of the first subtype range. 9141 -- This will be corrected before we are done, but right away we 9142 -- need to deal with the case where both bounds are non-negative. 9143 -- In this case, we set the low bound to the negative of the high 9144 -- bound, to make sure that the size is computed to include the 9145 -- required sign. Note that we do not need to worry about the 9146 -- case of both bounds negative, because the sign will be dealt 9147 -- with anyway. Furthermore we can't just go making such a bound 9148 -- symmetrical, since in a twos-complement system, there is an 9149 -- extra negative value which could not be accommodated on the 9150 -- positive side. 9151 9152 if Typ = Btyp 9153 and then not UR_Is_Negative (Loval) 9154 and then Hival > Loval 9155 then 9156 Loval := -Hival; 9157 Set_Realval (Lo, Loval); 9158 end if; 9159 9160 -- Compute the fudged bounds. If the bound is a model number, (or 9161 -- greater if given low bound, smaller if high bound) then we do 9162 -- nothing to include it, but we are allowed to backoff to the 9163 -- next adjacent model number when we exclude it. If it is not a 9164 -- model number then we straddle the two values with the model 9165 -- numbers on either side. 9166 9167 Model_Num := UR_Trunc (Loval / Small) * Small; 9168 9169 if UR_Ge (Loval, Model_Num) then 9170 Loval_Incl_EP := Model_Num; 9171 else 9172 Loval_Incl_EP := Model_Num - Small; 9173 end if; 9174 9175 -- The low value excluding the end point is Small greater, but 9176 -- we do not do this exclusion if the low value is positive, 9177 -- since it can't help the size and could actually hurt by 9178 -- crossing the high bound. 9179 9180 if UR_Is_Negative (Loval_Incl_EP) then 9181 Loval_Excl_EP := Loval_Incl_EP + Small; 9182 9183 -- If the value went from negative to zero, then we have the 9184 -- case where Loval_Incl_EP is the model number just below 9185 -- zero, so we want to stick to the negative value for the 9186 -- base type to maintain the condition that the size will 9187 -- include signed values. 9188 9189 if Typ = Btyp 9190 and then UR_Is_Zero (Loval_Excl_EP) 9191 then 9192 Loval_Excl_EP := Loval_Incl_EP; 9193 end if; 9194 9195 else 9196 Loval_Excl_EP := Loval_Incl_EP; 9197 end if; 9198 9199 -- Similar processing for upper bound and high value 9200 9201 Model_Num := UR_Trunc (Hival / Small) * Small; 9202 9203 if UR_Le (Hival, Model_Num) then 9204 Hival_Incl_EP := Model_Num; 9205 else 9206 Hival_Incl_EP := Model_Num + Small; 9207 end if; 9208 9209 if UR_Is_Positive (Hival_Incl_EP) then 9210 Hival_Excl_EP := Hival_Incl_EP - Small; 9211 else 9212 Hival_Excl_EP := Hival_Incl_EP; 9213 end if; 9214 9215 -- One further adjustment is needed. In the case of subtypes, we 9216 -- cannot go outside the range of the base type, or we get 9217 -- peculiarities, and the base type range is already set. This 9218 -- only applies to the Incl values, since clearly the Excl values 9219 -- are already as restricted as they are allowed to be. 9220 9221 if Typ /= Btyp then 9222 Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo)); 9223 Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi)); 9224 end if; 9225 9226 -- Get size including and excluding end points 9227 9228 Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP); 9229 Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP); 9230 9231 -- No need to exclude end-points if it does not reduce size 9232 9233 if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then 9234 Loval_Excl_EP := Loval_Incl_EP; 9235 end if; 9236 9237 if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then 9238 Hival_Excl_EP := Hival_Incl_EP; 9239 end if; 9240 9241 -- Now we set the actual size to be used. We want to use the 9242 -- bounds fudged up to include the end-points but only if this 9243 -- can be done without violating a specifically given size 9244 -- size clause or causing an unacceptable increase in size. 9245 9246 -- Case of size clause given 9247 9248 if Has_Size_Clause (Typ) then 9249 9250 -- Use the inclusive size only if it is consistent with 9251 -- the explicitly specified size. 9252 9253 if Size_Incl_EP <= RM_Size (Typ) then 9254 Actual_Lo := Loval_Incl_EP; 9255 Actual_Hi := Hival_Incl_EP; 9256 Actual_Size := Size_Incl_EP; 9257 9258 -- If the inclusive size is too large, we try excluding 9259 -- the end-points (will be caught later if does not work). 9260 9261 else 9262 Actual_Lo := Loval_Excl_EP; 9263 Actual_Hi := Hival_Excl_EP; 9264 Actual_Size := Size_Excl_EP; 9265 end if; 9266 9267 -- Case of size clause not given 9268 9269 else 9270 -- If we have a base type whose corresponding first subtype 9271 -- has an explicit size that is large enough to include our 9272 -- end-points, then do so. There is no point in working hard 9273 -- to get a base type whose size is smaller than the specified 9274 -- size of the first subtype. 9275 9276 if Has_Size_Clause (Ftyp) 9277 and then Size_Incl_EP <= Esize (Ftyp) 9278 then 9279 Actual_Size := Size_Incl_EP; 9280 Actual_Lo := Loval_Incl_EP; 9281 Actual_Hi := Hival_Incl_EP; 9282 9283 -- If excluding the end-points makes the size smaller and 9284 -- results in a size of 8,16,32,64, then we take the smaller 9285 -- size. For the 64 case, this is compulsory. For the other 9286 -- cases, it seems reasonable. We like to include end points 9287 -- if we can, but not at the expense of moving to the next 9288 -- natural boundary of size. 9289 9290 elsif Size_Incl_EP /= Size_Excl_EP 9291 and then Addressable (Size_Excl_EP) 9292 then 9293 Actual_Size := Size_Excl_EP; 9294 Actual_Lo := Loval_Excl_EP; 9295 Actual_Hi := Hival_Excl_EP; 9296 9297 -- Otherwise we can definitely include the end points 9298 9299 else 9300 Actual_Size := Size_Incl_EP; 9301 Actual_Lo := Loval_Incl_EP; 9302 Actual_Hi := Hival_Incl_EP; 9303 end if; 9304 9305 -- One pathological case: normally we never fudge a low bound 9306 -- down, since it would seem to increase the size (if it has 9307 -- any effect), but for ranges containing single value, or no 9308 -- values, the high bound can be small too large. Consider: 9309 9310 -- type t is delta 2.0**(-14) 9311 -- range 131072.0 .. 0; 9312 9313 -- That lower bound is *just* outside the range of 32 bits, and 9314 -- does need fudging down in this case. Note that the bounds 9315 -- will always have crossed here, since the high bound will be 9316 -- fudged down if necessary, as in the case of: 9317 9318 -- type t is delta 2.0**(-14) 9319 -- range 131072.0 .. 131072.0; 9320 9321 -- So we detect the situation by looking for crossed bounds, 9322 -- and if the bounds are crossed, and the low bound is greater 9323 -- than zero, we will always back it off by small, since this 9324 -- is completely harmless. 9325 9326 if Actual_Lo > Actual_Hi then 9327 if UR_Is_Positive (Actual_Lo) then 9328 Actual_Lo := Loval_Incl_EP - Small; 9329 Actual_Size := Fsize (Actual_Lo, Actual_Hi); 9330 9331 -- And of course, we need to do exactly the same parallel 9332 -- fudge for flat ranges in the negative region. 9333 9334 elsif UR_Is_Negative (Actual_Hi) then 9335 Actual_Hi := Hival_Incl_EP + Small; 9336 Actual_Size := Fsize (Actual_Lo, Actual_Hi); 9337 end if; 9338 end if; 9339 end if; 9340 9341 Set_Realval (Lo, Actual_Lo); 9342 Set_Realval (Hi, Actual_Hi); 9343 end Fudge; 9344 9345 -- Enforce some limitations for ordinary fixed-point types. They come 9346 -- from an exact algorithm used to implement Text_IO.Fixed_IO and the 9347 -- Fore, Image and Value attributes. The requirement on the Small is 9348 -- to lie in the range 2**(-(Siz - 1)) .. 2**(Siz - 1) for a type of 9349 -- Siz bits (Siz=32,64,128) and the requirement on the bounds is to 9350 -- be smaller in magnitude than 10.0**N * 2**(Siz - 1), where N is 9351 -- given by the formula N = floor ((Siz - 1) * log 2 / log 10). 9352 9353 -- If the bounds of a 32-bit type are too large, force 64-bit type 9354 9355 if Actual_Size <= 32 9356 and then Small <= Ureal_2_31 9357 and then (Smaller (Expr_Value_R (Lo), Ureal_M_2_10_18) 9358 or else Larger (Expr_Value_R (Hi), Ureal_2_10_18)) 9359 then 9360 Actual_Size := 33; 9361 end if; 9362 9363 -- If the bounds of a 64-bit type are too large, force 128-bit type 9364 9365 if System_Max_Integer_Size = 128 9366 and then Actual_Size <= 64 9367 and then Small <= Ureal_2_63 9368 and then (Smaller (Expr_Value_R (Lo), Ureal_M_9_10_36) 9369 or else Larger (Expr_Value_R (Hi), Ureal_9_10_36)) 9370 then 9371 Actual_Size := 65; 9372 end if; 9373 9374 -- Give error messages for first subtypes and not base types, as the 9375 -- bounds of base types are always maximum for their size, see below. 9376 9377 if System_Max_Integer_Size < 128 and then Typ /= Btyp then 9378 9379 -- See the 128-bit case below for the reason why we cannot test 9380 -- against the 2**(-63) .. 2**63 range. This quirk should have 9381 -- been kludged around as in the 128-bit case below, but it was 9382 -- not and we end up with a ludicrous range as a result??? 9383 9384 if Small < Ureal_2_M_80 then 9385 Error_Msg_Name_1 := Name_Small; 9386 Error_Msg_N 9387 ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", Typ); 9388 9389 elsif Small > Ureal_2_80 then 9390 Error_Msg_Name_1 := Name_Small; 9391 Error_Msg_N 9392 ("`&''%` too large, maximum allowed is 2.0'*'*80", Typ); 9393 end if; 9394 9395 if Smaller (Expr_Value_R (Lo), Ureal_M_9_10_36) then 9396 Error_Msg_Name_1 := Name_First; 9397 Error_Msg_N 9398 ("`&''%` too small, minimum allowed is -9.0E+36", Typ); 9399 end if; 9400 9401 if Larger (Expr_Value_R (Hi), Ureal_9_10_36) then 9402 Error_Msg_Name_1 := Name_Last; 9403 Error_Msg_N 9404 ("`&''%` too large, maximum allowed is 9.0E+36", Typ); 9405 end if; 9406 9407 elsif System_Max_Integer_Size = 128 and then Typ /= Btyp then 9408 9409 -- ACATS c35902d tests a delta equal to 2**(-(Max_Mantissa + 1)) 9410 -- but we cannot really support anything smaller than Fine_Delta 9411 -- because of the way we implement I/O for fixed point types??? 9412 9413 if Small = Ureal_2_M_128 then 9414 null; 9415 9416 elsif Small < Ureal_2_M_127 then 9417 Error_Msg_Name_1 := Name_Small; 9418 Error_Msg_N 9419 ("`&''%` too small, minimum allowed is 2.0'*'*(-127)", Typ); 9420 9421 elsif Small > Ureal_2_127 then 9422 Error_Msg_Name_1 := Name_Small; 9423 Error_Msg_N 9424 ("`&''%` too large, maximum allowed is 2.0'*'*127", Typ); 9425 end if; 9426 9427 if Actual_Size > 64 9428 and then (Norm_Num (Small) > Uint_2 ** 127 9429 or else Norm_Den (Small) > Uint_2 ** 127) 9430 and then Small /= Ureal_2_M_128 9431 then 9432 Error_Msg_Name_1 := Name_Small; 9433 Error_Msg_N 9434 ("`&''%` not the ratio of two 128-bit integers", Typ); 9435 end if; 9436 9437 if Smaller (Expr_Value_R (Lo), Ureal_M_10_76) then 9438 Error_Msg_Name_1 := Name_First; 9439 Error_Msg_N 9440 ("`&''%` too small, minimum allowed is -1.0E+76", Typ); 9441 end if; 9442 9443 if Larger (Expr_Value_R (Hi), Ureal_10_76) then 9444 Error_Msg_Name_1 := Name_Last; 9445 Error_Msg_N 9446 ("`&''%` too large, maximum allowed is 1.0E+76", Typ); 9447 end if; 9448 end if; 9449 9450 -- For the decimal case, none of this fudging is required, since there 9451 -- are no end-point problems in the decimal case (the end-points are 9452 -- always included). 9453 9454 else 9455 Actual_Size := Fsize (Loval, Hival); 9456 end if; 9457 9458 -- At this stage, the actual size has been calculated and the proper 9459 -- required bounds are stored in the low and high bounds. 9460 9461 if Actual_Size > System_Max_Integer_Size then 9462 Error_Msg_Uint_1 := UI_From_Int (Actual_Size); 9463 Error_Msg_Uint_2 := UI_From_Int (System_Max_Integer_Size); 9464 Error_Msg_N 9465 ("size required (^) for type& too large, maximum allowed is ^", 9466 Typ); 9467 Actual_Size := System_Max_Integer_Size; 9468 end if; 9469 9470 -- Check size against explicit given size 9471 9472 if Has_Size_Clause (Typ) then 9473 if Actual_Size > RM_Size (Typ) then 9474 Error_Msg_Uint_1 := RM_Size (Typ); 9475 Error_Msg_Uint_2 := UI_From_Int (Actual_Size); 9476 Error_Msg_NE 9477 ("size given (^) for type& too small, minimum allowed is ^", 9478 Size_Clause (Typ), Typ); 9479 9480 else 9481 Actual_Size := UI_To_Int (Esize (Typ)); 9482 end if; 9483 9484 -- Increase size to next natural boundary if no size clause given 9485 9486 else 9487 if Actual_Size <= 8 then 9488 Actual_Size := 8; 9489 elsif Actual_Size <= 16 then 9490 Actual_Size := 16; 9491 elsif Actual_Size <= 32 then 9492 Actual_Size := 32; 9493 elsif Actual_Size <= 64 then 9494 Actual_Size := 64; 9495 else 9496 Actual_Size := 128; 9497 end if; 9498 9499 Set_Esize (Typ, UI_From_Int (Actual_Size)); 9500 Adjust_Esize_For_Alignment (Typ); 9501 end if; 9502 9503 -- If we have a base type, then expand the bounds so that they extend to 9504 -- the full width of the allocated size in bits, to avoid junk range 9505 -- checks on intermediate computations. 9506 9507 if Typ = Btyp then 9508 Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1)))); 9509 Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1))); 9510 end if; 9511 9512 -- Final step is to reanalyze the bounds using the proper type 9513 -- and set the Corresponding_Integer_Value fields of the literals. 9514 9515 Set_Etype (Lo, Empty); 9516 Set_Analyzed (Lo, False); 9517 Analyze (Lo); 9518 9519 -- Resolve with universal fixed if the base type, and with the base 9520 -- type if we are freezing a subtype. Note we can't resolve the base 9521 -- type with itself, that would be a reference before definition. 9522 -- The resolution of the bounds of a subtype, if they are given by real 9523 -- literals, includes the setting of the Corresponding_Integer_Value, 9524 -- as for other literals of a fixed-point type. 9525 9526 if Typ = Btyp then 9527 Resolve (Lo, Universal_Fixed); 9528 Set_Corresponding_Integer_Value 9529 (Lo, UR_To_Uint (Realval (Lo) / Small)); 9530 else 9531 Resolve (Lo, Btyp); 9532 end if; 9533 9534 -- Similar processing for high bound 9535 9536 Set_Etype (Hi, Empty); 9537 Set_Analyzed (Hi, False); 9538 Analyze (Hi); 9539 9540 if Typ = Btyp then 9541 Resolve (Hi, Universal_Fixed); 9542 Set_Corresponding_Integer_Value 9543 (Hi, UR_To_Uint (Realval (Hi) / Small)); 9544 else 9545 Resolve (Hi, Btyp); 9546 end if; 9547 9548 -- Set type of range to correspond to bounds 9549 9550 Set_Etype (Rng, Etype (Lo)); 9551 9552 -- Set Esize to calculated size if not set already 9553 9554 if not Known_Esize (Typ) then 9555 Set_Esize (Typ, UI_From_Int (Actual_Size)); 9556 end if; 9557 9558 -- Set RM_Size if not already set. If already set, check value 9559 9560 declare 9561 Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ)); 9562 9563 begin 9564 if Known_RM_Size (Typ) then 9565 if RM_Size (Typ) < Minsiz then 9566 Error_Msg_Uint_1 := RM_Size (Typ); 9567 Error_Msg_Uint_2 := Minsiz; 9568 Error_Msg_NE 9569 ("size given (^) for type& too small, minimum allowed is ^", 9570 Size_Clause (Typ), Typ); 9571 end if; 9572 9573 else 9574 Set_RM_Size (Typ, Minsiz); 9575 end if; 9576 end; 9577 9578 -- Check for shaving 9579 9580 if Comes_From_Source (Typ) then 9581 9582 -- In SPARK mode the given bounds must be strictly representable 9583 9584 if SPARK_Mode = On then 9585 if Orig_Lo < Expr_Value_R (Lo) then 9586 Error_Msg_NE 9587 ("declared low bound of type & is outside type range", 9588 Lo, Typ); 9589 end if; 9590 9591 if Orig_Hi > Expr_Value_R (Hi) then 9592 Error_Msg_NE 9593 ("declared high bound of type & is outside type range", 9594 Hi, Typ); 9595 end if; 9596 9597 else 9598 if Orig_Lo < Expr_Value_R (Lo) then 9599 Error_Msg_N 9600 ("declared low bound of type & is outside type range??", Typ); 9601 Error_Msg_N 9602 ("\low bound adjusted up by delta (RM 3.5.9(13))??", Typ); 9603 end if; 9604 9605 if Orig_Hi > Expr_Value_R (Hi) then 9606 Error_Msg_N 9607 ("declared high bound of type & is outside type range??", 9608 Typ); 9609 Error_Msg_N 9610 ("\high bound adjusted down by delta (RM 3.5.9(13))??", Typ); 9611 end if; 9612 end if; 9613 end if; 9614 end Freeze_Fixed_Point_Type; 9615 9616 ------------------ 9617 -- Freeze_Itype -- 9618 ------------------ 9619 9620 procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is 9621 L : List_Id; 9622 9623 begin 9624 Set_Has_Delayed_Freeze (T); 9625 L := Freeze_Entity (T, N); 9626 9627 if Is_Non_Empty_List (L) then 9628 Insert_Actions (N, L); 9629 end if; 9630 end Freeze_Itype; 9631 9632 -------------------------- 9633 -- Freeze_Static_Object -- 9634 -------------------------- 9635 9636 procedure Freeze_Static_Object (E : Entity_Id) is 9637 9638 Cannot_Be_Static : exception; 9639 -- Exception raised if the type of a static object cannot be made 9640 -- static. This happens if the type depends on non-global objects. 9641 9642 procedure Ensure_Expression_Is_SA (N : Node_Id); 9643 -- Called to ensure that an expression used as part of a type definition 9644 -- is statically allocatable, which means that the expression type is 9645 -- statically allocatable, and the expression is either static, or a 9646 -- reference to a library level constant. 9647 9648 procedure Ensure_Type_Is_SA (Typ : Entity_Id); 9649 -- Called to mark a type as static, checking that it is possible 9650 -- to set the type as static. If it is not possible, then the 9651 -- exception Cannot_Be_Static is raised. 9652 9653 ----------------------------- 9654 -- Ensure_Expression_Is_SA -- 9655 ----------------------------- 9656 9657 procedure Ensure_Expression_Is_SA (N : Node_Id) is 9658 Ent : Entity_Id; 9659 9660 begin 9661 Ensure_Type_Is_SA (Etype (N)); 9662 9663 if Is_OK_Static_Expression (N) then 9664 return; 9665 9666 elsif Nkind (N) = N_Identifier then 9667 Ent := Entity (N); 9668 9669 if Present (Ent) 9670 and then Ekind (Ent) = E_Constant 9671 and then Is_Library_Level_Entity (Ent) 9672 then 9673 return; 9674 end if; 9675 end if; 9676 9677 raise Cannot_Be_Static; 9678 end Ensure_Expression_Is_SA; 9679 9680 ----------------------- 9681 -- Ensure_Type_Is_SA -- 9682 ----------------------- 9683 9684 procedure Ensure_Type_Is_SA (Typ : Entity_Id) is 9685 N : Node_Id; 9686 C : Entity_Id; 9687 9688 begin 9689 -- If type is library level, we are all set 9690 9691 if Is_Library_Level_Entity (Typ) then 9692 return; 9693 end if; 9694 9695 -- We are also OK if the type already marked as statically allocated, 9696 -- which means we processed it before. 9697 9698 if Is_Statically_Allocated (Typ) then 9699 return; 9700 end if; 9701 9702 -- Mark type as statically allocated 9703 9704 Set_Is_Statically_Allocated (Typ); 9705 9706 -- Check that it is safe to statically allocate this type 9707 9708 if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then 9709 Ensure_Expression_Is_SA (Type_Low_Bound (Typ)); 9710 Ensure_Expression_Is_SA (Type_High_Bound (Typ)); 9711 9712 elsif Is_Array_Type (Typ) then 9713 N := First_Index (Typ); 9714 while Present (N) loop 9715 Ensure_Type_Is_SA (Etype (N)); 9716 Next_Index (N); 9717 end loop; 9718 9719 Ensure_Type_Is_SA (Component_Type (Typ)); 9720 9721 elsif Is_Access_Type (Typ) then 9722 if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then 9723 9724 declare 9725 F : Entity_Id; 9726 T : constant Entity_Id := Etype (Designated_Type (Typ)); 9727 9728 begin 9729 if T /= Standard_Void_Type then 9730 Ensure_Type_Is_SA (T); 9731 end if; 9732 9733 F := First_Formal (Designated_Type (Typ)); 9734 while Present (F) loop 9735 Ensure_Type_Is_SA (Etype (F)); 9736 Next_Formal (F); 9737 end loop; 9738 end; 9739 9740 else 9741 Ensure_Type_Is_SA (Designated_Type (Typ)); 9742 end if; 9743 9744 elsif Is_Record_Type (Typ) then 9745 C := First_Entity (Typ); 9746 while Present (C) loop 9747 if Ekind (C) = E_Discriminant 9748 or else Ekind (C) = E_Component 9749 then 9750 Ensure_Type_Is_SA (Etype (C)); 9751 9752 elsif Is_Type (C) then 9753 Ensure_Type_Is_SA (C); 9754 end if; 9755 9756 Next_Entity (C); 9757 end loop; 9758 9759 elsif Ekind (Typ) = E_Subprogram_Type then 9760 Ensure_Type_Is_SA (Etype (Typ)); 9761 9762 C := First_Formal (Typ); 9763 while Present (C) loop 9764 Ensure_Type_Is_SA (Etype (C)); 9765 Next_Formal (C); 9766 end loop; 9767 9768 else 9769 raise Cannot_Be_Static; 9770 end if; 9771 end Ensure_Type_Is_SA; 9772 9773 -- Start of processing for Freeze_Static_Object 9774 9775 begin 9776 Ensure_Type_Is_SA (Etype (E)); 9777 9778 exception 9779 when Cannot_Be_Static => 9780 9781 -- If the object that cannot be static is imported or exported, then 9782 -- issue an error message saying that this object cannot be imported 9783 -- or exported. If it has an address clause it is an overlay in the 9784 -- current partition and the static requirement is not relevant. 9785 -- Do not issue any error message when ignoring rep clauses. 9786 9787 if Ignore_Rep_Clauses then 9788 null; 9789 9790 elsif Is_Imported (E) then 9791 if No (Address_Clause (E)) then 9792 Error_Msg_N 9793 ("& cannot be imported (local type is not constant)", E); 9794 end if; 9795 9796 -- Otherwise must be exported, something is wrong if compiler 9797 -- is marking something as statically allocated which cannot be). 9798 9799 else pragma Assert (Is_Exported (E)); 9800 Error_Msg_N 9801 ("& cannot be exported (local type is not constant)", E); 9802 end if; 9803 end Freeze_Static_Object; 9804 9805 ----------------------- 9806 -- Freeze_Subprogram -- 9807 ----------------------- 9808 9809 procedure Freeze_Subprogram (E : Entity_Id) is 9810 function Check_Extra_Formals (E : Entity_Id) return Boolean; 9811 -- Return True if the decoration of the attributes associated with extra 9812 -- formals are properly set. 9813 9814 procedure Set_Profile_Convention (Subp_Id : Entity_Id); 9815 -- Set the conventions of all anonymous access-to-subprogram formals and 9816 -- result subtype of subprogram Subp_Id to the convention of Subp_Id. 9817 9818 ------------------------- 9819 -- Check_Extra_Formals -- 9820 ------------------------- 9821 9822 function Check_Extra_Formals (E : Entity_Id) return Boolean is 9823 Last_Formal : Entity_Id := Empty; 9824 Formal : Entity_Id; 9825 Has_Extra_Formals : Boolean := False; 9826 9827 begin 9828 -- No check required if expansion is disabled because extra 9829 -- formals are only generated when we are generating code. 9830 -- See Create_Extra_Formals. 9831 9832 if not Expander_Active then 9833 return True; 9834 end if; 9835 9836 -- Check attribute Extra_Formal: If available, it must be set only 9837 -- on the last formal of E. 9838 9839 Formal := First_Formal (E); 9840 while Present (Formal) loop 9841 if Present (Extra_Formal (Formal)) then 9842 if Has_Extra_Formals then 9843 return False; 9844 end if; 9845 9846 Has_Extra_Formals := True; 9847 end if; 9848 9849 Last_Formal := Formal; 9850 Next_Formal (Formal); 9851 end loop; 9852 9853 -- Check attribute Extra_Accessibility_Of_Result 9854 9855 if Ekind (E) in E_Function | E_Subprogram_Type 9856 and then Needs_Result_Accessibility_Level (E) 9857 and then No (Extra_Accessibility_Of_Result (E)) 9858 then 9859 return False; 9860 end if; 9861 9862 -- Check attribute Extra_Formals: If E has extra formals, then this 9863 -- attribute must point to the first extra formal of E. 9864 9865 if Has_Extra_Formals then 9866 return Present (Extra_Formals (E)) 9867 and then Present (Extra_Formal (Last_Formal)) 9868 and then Extra_Formal (Last_Formal) = Extra_Formals (E); 9869 9870 -- When E has no formals, the first extra formal is available through 9871 -- the Extra_Formals attribute. 9872 9873 elsif Present (Extra_Formals (E)) then 9874 return No (First_Formal (E)); 9875 9876 else 9877 return True; 9878 end if; 9879 end Check_Extra_Formals; 9880 9881 ---------------------------- 9882 -- Set_Profile_Convention -- 9883 ---------------------------- 9884 9885 procedure Set_Profile_Convention (Subp_Id : Entity_Id) is 9886 Conv : constant Convention_Id := Convention (Subp_Id); 9887 9888 procedure Set_Type_Convention (Typ : Entity_Id); 9889 -- Set the convention of anonymous access-to-subprogram type Typ and 9890 -- its designated type to Conv. 9891 9892 ------------------------- 9893 -- Set_Type_Convention -- 9894 ------------------------- 9895 9896 procedure Set_Type_Convention (Typ : Entity_Id) is 9897 begin 9898 -- Set the convention on both the anonymous access-to-subprogram 9899 -- type and the subprogram type it points to because both types 9900 -- participate in conformance-related checks. 9901 9902 if Ekind (Typ) = E_Anonymous_Access_Subprogram_Type then 9903 Set_Convention (Typ, Conv); 9904 Set_Convention (Designated_Type (Typ), Conv); 9905 end if; 9906 end Set_Type_Convention; 9907 9908 -- Local variables 9909 9910 Formal : Entity_Id; 9911 9912 -- Start of processing for Set_Profile_Convention 9913 9914 begin 9915 Formal := First_Formal (Subp_Id); 9916 while Present (Formal) loop 9917 Set_Type_Convention (Etype (Formal)); 9918 Next_Formal (Formal); 9919 end loop; 9920 9921 if Ekind (Subp_Id) = E_Function then 9922 Set_Type_Convention (Etype (Subp_Id)); 9923 end if; 9924 end Set_Profile_Convention; 9925 9926 -- Local variables 9927 9928 F : Entity_Id; 9929 Retype : Entity_Id; 9930 9931 -- Start of processing for Freeze_Subprogram 9932 9933 begin 9934 -- Subprogram may not have an address clause unless it is imported 9935 9936 if Present (Address_Clause (E)) then 9937 if not Is_Imported (E) then 9938 Error_Msg_N 9939 ("address clause can only be given for imported subprogram", 9940 Name (Address_Clause (E))); 9941 end if; 9942 end if; 9943 9944 -- Reset the Pure indication on an imported subprogram unless an 9945 -- explicit Pure_Function pragma was present or the subprogram is an 9946 -- intrinsic. We do this because otherwise it is an insidious error 9947 -- to call a non-pure function from pure unit and have calls 9948 -- mysteriously optimized away. What happens here is that the Import 9949 -- can bypass the normal check to ensure that pure units call only pure 9950 -- subprograms. 9951 9952 -- The reason for the intrinsic exception is that in general, intrinsic 9953 -- functions (such as shifts) are pure anyway. The only exceptions are 9954 -- the intrinsics in GNAT.Source_Info, and that unit is not marked Pure 9955 -- in any case, so no problem arises. 9956 9957 if Is_Imported (E) 9958 and then Is_Pure (E) 9959 and then not Has_Pragma_Pure_Function (E) 9960 and then not Is_Intrinsic_Subprogram (E) 9961 then 9962 Set_Is_Pure (E, False); 9963 end if; 9964 9965 -- For C++ constructors check that their external name has been given 9966 -- (either in pragma CPP_Constructor or in a pragma import). 9967 9968 if Is_Constructor (E) 9969 and then Convention (E) = Convention_CPP 9970 and then 9971 (No (Interface_Name (E)) 9972 or else String_Equal 9973 (L => Strval (Interface_Name (E)), 9974 R => Strval (Get_Default_External_Name (E)))) 9975 then 9976 Error_Msg_N 9977 ("'C++ constructor must have external name or link name", E); 9978 end if; 9979 9980 -- We also reset the Pure indication on a subprogram with an Address 9981 -- parameter, because the parameter may be used as a pointer and the 9982 -- referenced data may change even if the address value does not. 9983 9984 -- Note that if the programmer gave an explicit Pure_Function pragma, 9985 -- then we believe the programmer, and leave the subprogram Pure. We 9986 -- also suppress this check on run-time files. 9987 9988 if Is_Pure (E) 9989 and then Is_Subprogram (E) 9990 and then not Has_Pragma_Pure_Function (E) 9991 and then not Is_Internal_Unit (Current_Sem_Unit) 9992 then 9993 Check_Function_With_Address_Parameter (E); 9994 end if; 9995 9996 -- Ensure that all anonymous access-to-subprogram types inherit the 9997 -- convention of their related subprogram (RM 6.3.1(13.1/5)). This is 9998 -- not done for a defaulted convention Ada because those types also 9999 -- default to Ada. Convention Protected must not be propagated when 10000 -- the subprogram is an entry because this would be illegal. The only 10001 -- way to force convention Protected on these kinds of types is to 10002 -- include keyword "protected" in the access definition. Conventions 10003 -- Entry and Intrinsic are also not propagated (specified by AI12-0207). 10004 10005 if Convention (E) /= Convention_Ada 10006 and then Convention (E) /= Convention_Protected 10007 and then Convention (E) /= Convention_Entry 10008 and then Convention (E) /= Convention_Intrinsic 10009 then 10010 Set_Profile_Convention (E); 10011 end if; 10012 10013 -- For non-foreign convention subprograms, this is where we create 10014 -- the extra formals (for accessibility level and constrained bit 10015 -- information). We delay this till the freeze point precisely so 10016 -- that we know the convention. 10017 10018 if not Has_Foreign_Convention (E) then 10019 if No (Extra_Formals (E)) then 10020 10021 -- Extra formals are shared by derived subprograms; therefore, if 10022 -- the ultimate alias of E has been frozen before E then the extra 10023 -- formals have been added, but the attribute Extra_Formals is 10024 -- still unset (and must be set now). 10025 10026 if Present (Alias (E)) 10027 and then Is_Frozen (Ultimate_Alias (E)) 10028 and then Present (Extra_Formals (Ultimate_Alias (E))) 10029 and then Last_Formal (Ultimate_Alias (E)) = Last_Formal (E) 10030 then 10031 Set_Extra_Formals (E, Extra_Formals (Ultimate_Alias (E))); 10032 10033 if Ekind (E) = E_Function then 10034 Set_Extra_Accessibility_Of_Result (E, 10035 Extra_Accessibility_Of_Result (Ultimate_Alias (E))); 10036 end if; 10037 else 10038 Create_Extra_Formals (E); 10039 end if; 10040 end if; 10041 10042 pragma Assert (Check_Extra_Formals (E)); 10043 Set_Mechanisms (E); 10044 10045 -- If this is convention Ada and a Valued_Procedure, that's odd 10046 10047 if Ekind (E) = E_Procedure 10048 and then Is_Valued_Procedure (E) 10049 and then Convention (E) = Convention_Ada 10050 and then Warn_On_Export_Import 10051 then 10052 Error_Msg_N 10053 ("??Valued_Procedure has no effect for convention Ada", E); 10054 Set_Is_Valued_Procedure (E, False); 10055 end if; 10056 10057 -- Case of foreign convention 10058 10059 else 10060 Set_Mechanisms (E); 10061 10062 -- For foreign conventions, warn about return of unconstrained array 10063 10064 if Ekind (E) = E_Function then 10065 Retype := Underlying_Type (Etype (E)); 10066 10067 -- If no return type, probably some other error, e.g. a 10068 -- missing full declaration, so ignore. 10069 10070 if No (Retype) then 10071 null; 10072 10073 -- If the return type is generic, we have emitted a warning 10074 -- earlier on, and there is nothing else to check here. Specific 10075 -- instantiations may lead to erroneous behavior. 10076 10077 elsif Is_Generic_Type (Etype (E)) then 10078 null; 10079 10080 -- Display warning if returning unconstrained array 10081 10082 elsif Is_Array_Type (Retype) 10083 and then not Is_Constrained (Retype) 10084 10085 -- Check appropriate warning is enabled (should we check for 10086 -- Warnings (Off) on specific entities here, probably so???) 10087 10088 and then Warn_On_Export_Import 10089 then 10090 Error_Msg_N 10091 ("?x?foreign convention function& should not return " & 10092 "unconstrained array", E); 10093 return; 10094 end if; 10095 end if; 10096 10097 -- If any of the formals for an exported foreign convention 10098 -- subprogram have defaults, then emit an appropriate warning since 10099 -- this is odd (default cannot be used from non-Ada code) 10100 10101 if Is_Exported (E) then 10102 F := First_Formal (E); 10103 while Present (F) loop 10104 if Warn_On_Export_Import 10105 and then Present (Default_Value (F)) 10106 then 10107 Error_Msg_N 10108 ("?x?parameter cannot be defaulted in non-Ada call", 10109 Default_Value (F)); 10110 end if; 10111 10112 Next_Formal (F); 10113 end loop; 10114 end if; 10115 end if; 10116 10117 -- Pragma Inline_Always is disallowed for dispatching subprograms 10118 -- because the address of such subprograms is saved in the dispatch 10119 -- table to support dispatching calls, and dispatching calls cannot 10120 -- be inlined. This is consistent with the restriction against using 10121 -- 'Access or 'Address on an Inline_Always subprogram. 10122 10123 if Is_Dispatching_Operation (E) 10124 and then Has_Pragma_Inline_Always (E) 10125 then 10126 Error_Msg_N 10127 ("pragma Inline_Always not allowed for dispatching subprograms", E); 10128 end if; 10129 10130 -- Because of the implicit representation of inherited predefined 10131 -- operators in the front-end, the overriding status of the operation 10132 -- may be affected when a full view of a type is analyzed, and this is 10133 -- not captured by the analysis of the corresponding type declaration. 10134 -- Therefore the correctness of a not-overriding indicator must be 10135 -- rechecked when the subprogram is frozen. 10136 10137 if Nkind (E) = N_Defining_Operator_Symbol 10138 and then not Error_Posted (Parent (E)) 10139 then 10140 Check_Overriding_Indicator (E, Empty, Is_Primitive (E)); 10141 end if; 10142 10143 Retype := Get_Fullest_View (Etype (E)); 10144 10145 if Transform_Function_Array 10146 and then Nkind (Parent (E)) = N_Function_Specification 10147 and then Is_Array_Type (Retype) 10148 and then Is_Constrained (Retype) 10149 and then not Is_Unchecked_Conversion_Instance (E) 10150 and then not Rewritten_For_C (E) 10151 then 10152 Build_Procedure_Form (Unit_Declaration_Node (E)); 10153 end if; 10154 end Freeze_Subprogram; 10155 10156 ---------------------- 10157 -- Is_Fully_Defined -- 10158 ---------------------- 10159 10160 function Is_Fully_Defined (T : Entity_Id) return Boolean is 10161 begin 10162 if Ekind (T) = E_Class_Wide_Type then 10163 return Is_Fully_Defined (Etype (T)); 10164 10165 elsif Is_Array_Type (T) then 10166 return Is_Fully_Defined (Component_Type (T)); 10167 10168 elsif Is_Record_Type (T) 10169 and not Is_Private_Type (T) 10170 then 10171 -- Verify that the record type has no components with private types 10172 -- without completion. 10173 10174 declare 10175 Comp : Entity_Id; 10176 10177 begin 10178 Comp := First_Component (T); 10179 while Present (Comp) loop 10180 if not Is_Fully_Defined (Etype (Comp)) then 10181 return False; 10182 end if; 10183 10184 Next_Component (Comp); 10185 end loop; 10186 return True; 10187 end; 10188 10189 -- For the designated type of an access to subprogram, all types in 10190 -- the profile must be fully defined. 10191 10192 elsif Ekind (T) = E_Subprogram_Type then 10193 declare 10194 F : Entity_Id; 10195 10196 begin 10197 F := First_Formal (T); 10198 while Present (F) loop 10199 if not Is_Fully_Defined (Etype (F)) then 10200 return False; 10201 end if; 10202 10203 Next_Formal (F); 10204 end loop; 10205 10206 return Is_Fully_Defined (Etype (T)); 10207 end; 10208 10209 else 10210 return not Is_Private_Type (T) 10211 or else Present (Full_View (Base_Type (T))); 10212 end if; 10213 end Is_Fully_Defined; 10214 10215 --------------------------------- 10216 -- Process_Default_Expressions -- 10217 --------------------------------- 10218 10219 procedure Process_Default_Expressions 10220 (E : Entity_Id; 10221 After : in out Node_Id) 10222 is 10223 Loc : constant Source_Ptr := Sloc (E); 10224 Dbody : Node_Id; 10225 Formal : Node_Id; 10226 Dcopy : Node_Id; 10227 Dnam : Entity_Id; 10228 10229 begin 10230 Set_Default_Expressions_Processed (E); 10231 10232 -- A subprogram instance and its associated anonymous subprogram share 10233 -- their signature. The default expression functions are defined in the 10234 -- wrapper packages for the anonymous subprogram, and should not be 10235 -- generated again for the instance. 10236 10237 if Is_Generic_Instance (E) 10238 and then Present (Alias (E)) 10239 and then Default_Expressions_Processed (Alias (E)) 10240 then 10241 return; 10242 end if; 10243 10244 Formal := First_Formal (E); 10245 while Present (Formal) loop 10246 if Present (Default_Value (Formal)) then 10247 10248 -- We work with a copy of the default expression because we 10249 -- do not want to disturb the original, since this would mess 10250 -- up the conformance checking. 10251 10252 Dcopy := New_Copy_Tree (Default_Value (Formal)); 10253 10254 -- The analysis of the expression may generate insert actions, 10255 -- which of course must not be executed. We wrap those actions 10256 -- in a procedure that is not called, and later on eliminated. 10257 -- The following cases have no side effects, and are analyzed 10258 -- directly. 10259 10260 if Nkind (Dcopy) = N_Identifier 10261 or else Nkind (Dcopy) in N_Expanded_Name 10262 | N_Integer_Literal 10263 | N_Character_Literal 10264 | N_String_Literal 10265 | N_Real_Literal 10266 or else (Nkind (Dcopy) = N_Attribute_Reference 10267 and then Attribute_Name (Dcopy) = Name_Null_Parameter) 10268 or else Known_Null (Dcopy) 10269 then 10270 -- If there is no default function, we must still do a full 10271 -- analyze call on the default value, to ensure that all error 10272 -- checks are performed, e.g. those associated with static 10273 -- evaluation. Note: this branch will always be taken if the 10274 -- analyzer is turned off (but we still need the error checks). 10275 10276 -- Note: the setting of parent here is to meet the requirement 10277 -- that we can only analyze the expression while attached to 10278 -- the tree. Really the requirement is that the parent chain 10279 -- be set, we don't actually need to be in the tree. 10280 10281 Set_Parent (Dcopy, Declaration_Node (Formal)); 10282 Analyze (Dcopy); 10283 10284 -- Default expressions are resolved with their own type if the 10285 -- context is generic, to avoid anomalies with private types. 10286 10287 if Ekind (Scope (E)) = E_Generic_Package then 10288 Resolve (Dcopy); 10289 else 10290 Resolve (Dcopy, Etype (Formal)); 10291 end if; 10292 10293 -- If that resolved expression will raise constraint error, 10294 -- then flag the default value as raising constraint error. 10295 -- This allows a proper error message on the calls. 10296 10297 if Raises_Constraint_Error (Dcopy) then 10298 Set_Raises_Constraint_Error (Default_Value (Formal)); 10299 end if; 10300 10301 -- If the default is a parameterless call, we use the name of 10302 -- the called function directly, and there is no body to build. 10303 10304 elsif Nkind (Dcopy) = N_Function_Call 10305 and then No (Parameter_Associations (Dcopy)) 10306 then 10307 null; 10308 10309 -- Else construct and analyze the body of a wrapper procedure 10310 -- that contains an object declaration to hold the expression. 10311 -- Given that this is done only to complete the analysis, it is 10312 -- simpler to build a procedure than a function which might 10313 -- involve secondary stack expansion. 10314 10315 else 10316 Dnam := Make_Temporary (Loc, 'D'); 10317 10318 Dbody := 10319 Make_Subprogram_Body (Loc, 10320 Specification => 10321 Make_Procedure_Specification (Loc, 10322 Defining_Unit_Name => Dnam), 10323 10324 Declarations => New_List ( 10325 Make_Object_Declaration (Loc, 10326 Defining_Identifier => Make_Temporary (Loc, 'T'), 10327 Object_Definition => 10328 New_Occurrence_Of (Etype (Formal), Loc), 10329 Expression => New_Copy_Tree (Dcopy))), 10330 10331 Handled_Statement_Sequence => 10332 Make_Handled_Sequence_Of_Statements (Loc, 10333 Statements => Empty_List)); 10334 10335 Set_Scope (Dnam, Scope (E)); 10336 Set_Assignment_OK (First (Declarations (Dbody))); 10337 Set_Is_Eliminated (Dnam); 10338 Insert_After (After, Dbody); 10339 Analyze (Dbody); 10340 After := Dbody; 10341 end if; 10342 end if; 10343 10344 Next_Formal (Formal); 10345 end loop; 10346 end Process_Default_Expressions; 10347 10348 ---------------------------------------- 10349 -- Set_Component_Alignment_If_Not_Set -- 10350 ---------------------------------------- 10351 10352 procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is 10353 begin 10354 -- Ignore if not base type, subtypes don't need anything 10355 10356 if Typ /= Base_Type (Typ) then 10357 return; 10358 end if; 10359 10360 -- Do not override existing representation 10361 10362 if Is_Packed (Typ) then 10363 return; 10364 10365 elsif Has_Specified_Layout (Typ) then 10366 return; 10367 10368 elsif Component_Alignment (Typ) /= Calign_Default then 10369 return; 10370 10371 else 10372 Set_Component_Alignment 10373 (Typ, Scope_Stack.Table 10374 (Scope_Stack.Last).Component_Alignment_Default); 10375 end if; 10376 end Set_Component_Alignment_If_Not_Set; 10377 10378 -------------------------- 10379 -- Set_SSO_From_Default -- 10380 -------------------------- 10381 10382 procedure Set_SSO_From_Default (T : Entity_Id) is 10383 Reversed : Boolean; 10384 10385 begin 10386 -- Set default SSO for an array or record base type, except in case of 10387 -- a type extension (which always inherits the SSO of its parent type). 10388 10389 if Is_Base_Type (T) 10390 and then (Is_Array_Type (T) 10391 or else (Is_Record_Type (T) 10392 and then not (Is_Tagged_Type (T) 10393 and then Is_Derived_Type (T)))) 10394 then 10395 Reversed := 10396 (Bytes_Big_Endian and then SSO_Set_Low_By_Default (T)) 10397 or else 10398 (not Bytes_Big_Endian and then SSO_Set_High_By_Default (T)); 10399 10400 if (SSO_Set_Low_By_Default (T) or else SSO_Set_High_By_Default (T)) 10401 10402 -- For a record type, if bit order is specified explicitly, 10403 -- then do not set SSO from default if not consistent. Note that 10404 -- we do not want to look at a Bit_Order attribute definition 10405 -- for a parent: if we were to inherit Bit_Order, then both 10406 -- SSO_Set_*_By_Default flags would have been cleared already 10407 -- (by Inherit_Aspects_At_Freeze_Point). 10408 10409 and then not 10410 (Is_Record_Type (T) 10411 and then 10412 Has_Rep_Item (T, Name_Bit_Order, Check_Parents => False) 10413 and then Reverse_Bit_Order (T) /= Reversed) 10414 then 10415 -- If flags cause reverse storage order, then set the result. Note 10416 -- that we would have ignored the pragma setting the non default 10417 -- storage order in any case, hence the assertion at this point. 10418 10419 pragma Assert 10420 (not Reversed or else Support_Nondefault_SSO_On_Target); 10421 10422 Set_Reverse_Storage_Order (T, Reversed); 10423 10424 -- For a record type, also set reversed bit order. Note: if a bit 10425 -- order has been specified explicitly, then this is a no-op. 10426 10427 if Is_Record_Type (T) then 10428 Set_Reverse_Bit_Order (T, Reversed); 10429 end if; 10430 end if; 10431 end if; 10432 end Set_SSO_From_Default; 10433 10434 ------------------ 10435 -- Undelay_Type -- 10436 ------------------ 10437 10438 procedure Undelay_Type (T : Entity_Id) is 10439 begin 10440 Set_Has_Delayed_Freeze (T, False); 10441 Set_Freeze_Node (T, Empty); 10442 10443 -- Since we don't want T to have a Freeze_Node, we don't want its 10444 -- Full_View or Corresponding_Record_Type to have one either. 10445 10446 -- ??? Fundamentally, this whole handling is unpleasant. What we really 10447 -- want is to be sure that for an Itype that's part of record R and is a 10448 -- subtype of type T, that it's frozen after the later of the freeze 10449 -- points of R and T. We have no way of doing that directly, so what we 10450 -- do is force most such Itypes to be frozen as part of freezing R via 10451 -- this procedure and only delay the ones that need to be delayed 10452 -- (mostly the designated types of access types that are defined as part 10453 -- of the record). 10454 10455 if Is_Private_Type (T) 10456 and then Present (Full_View (T)) 10457 and then Is_Itype (Full_View (T)) 10458 and then Is_Record_Type (Scope (Full_View (T))) 10459 then 10460 Undelay_Type (Full_View (T)); 10461 end if; 10462 10463 if Is_Concurrent_Type (T) 10464 and then Present (Corresponding_Record_Type (T)) 10465 and then Is_Itype (Corresponding_Record_Type (T)) 10466 and then Is_Record_Type (Scope (Corresponding_Record_Type (T))) 10467 then 10468 Undelay_Type (Corresponding_Record_Type (T)); 10469 end if; 10470 end Undelay_Type; 10471 10472 ------------------ 10473 -- Warn_Overlay -- 10474 ------------------ 10475 10476 procedure Warn_Overlay (Expr : Node_Id; Typ : Entity_Id; Nam : Node_Id) is 10477 Ent : constant Entity_Id := Entity (Nam); 10478 -- The object to which the address clause applies 10479 10480 Init : Node_Id; 10481 Old : Entity_Id := Empty; 10482 Decl : Node_Id; 10483 10484 begin 10485 -- No warning if address clause overlay warnings are off 10486 10487 if not Address_Clause_Overlay_Warnings then 10488 return; 10489 end if; 10490 10491 -- No warning if there is an explicit initialization 10492 10493 Init := Original_Node (Expression (Declaration_Node (Ent))); 10494 10495 if Present (Init) and then Comes_From_Source (Init) then 10496 return; 10497 end if; 10498 10499 -- We only give the warning for non-imported entities of a type for 10500 -- which a non-null base init proc is defined, or for objects of access 10501 -- types with implicit null initialization, or when Normalize_Scalars 10502 -- applies and the type is scalar or a string type (the latter being 10503 -- tested for because predefined String types are initialized by inline 10504 -- code rather than by an init_proc). Note that we do not give the 10505 -- warning for Initialize_Scalars, since we suppressed initialization 10506 -- in this case. Also, do not warn if Suppress_Initialization is set 10507 -- either on the type, or on the object via pragma or aspect. 10508 10509 if Present (Expr) 10510 and then not Is_Imported (Ent) 10511 and then not Initialization_Suppressed (Typ) 10512 and then not (Ekind (Ent) = E_Variable 10513 and then Initialization_Suppressed (Ent)) 10514 and then (Has_Non_Null_Base_Init_Proc (Typ) 10515 or else Is_Access_Type (Typ) 10516 or else (Normalize_Scalars 10517 and then (Is_Scalar_Type (Typ) 10518 or else Is_String_Type (Typ)))) 10519 then 10520 if Nkind (Expr) = N_Attribute_Reference 10521 and then Is_Entity_Name (Prefix (Expr)) 10522 then 10523 Old := Entity (Prefix (Expr)); 10524 10525 elsif Is_Entity_Name (Expr) 10526 and then Ekind (Entity (Expr)) = E_Constant 10527 then 10528 Decl := Declaration_Node (Entity (Expr)); 10529 10530 if Nkind (Decl) = N_Object_Declaration 10531 and then Present (Expression (Decl)) 10532 and then Nkind (Expression (Decl)) = N_Attribute_Reference 10533 and then Is_Entity_Name (Prefix (Expression (Decl))) 10534 then 10535 Old := Entity (Prefix (Expression (Decl))); 10536 10537 elsif Nkind (Expr) = N_Function_Call then 10538 return; 10539 end if; 10540 10541 -- A function call (most likely to To_Address) is probably not an 10542 -- overlay, so skip warning. Ditto if the function call was inlined 10543 -- and transformed into an entity. 10544 10545 elsif Nkind (Original_Node (Expr)) = N_Function_Call then 10546 return; 10547 end if; 10548 10549 -- If a pragma Import follows, we assume that it is for the current 10550 -- target of the address clause, and skip the warning. There may be 10551 -- a source pragma or an aspect that specifies import and generates 10552 -- the corresponding pragma. These will indicate that the entity is 10553 -- imported and that is checked above so that the spurious warning 10554 -- (generated when the entity is frozen) will be suppressed. The 10555 -- pragma may be attached to the aspect, so it is not yet a list 10556 -- member. 10557 10558 if Is_List_Member (Parent (Expr)) then 10559 Decl := Next (Parent (Expr)); 10560 10561 if Present (Decl) 10562 and then Nkind (Decl) = N_Pragma 10563 and then Pragma_Name (Decl) = Name_Import 10564 then 10565 return; 10566 end if; 10567 end if; 10568 10569 -- Otherwise give warning message 10570 10571 if Present (Old) then 10572 Error_Msg_Node_2 := Old; 10573 Error_Msg_N 10574 ("default initialization of & may modify &??", 10575 Nam); 10576 else 10577 Error_Msg_N 10578 ("default initialization of & may modify overlaid storage??", 10579 Nam); 10580 end if; 10581 10582 -- Add friendly warning if initialization comes from a packed array 10583 -- component. 10584 10585 if Is_Record_Type (Typ) then 10586 declare 10587 Comp : Entity_Id; 10588 10589 begin 10590 Comp := First_Component (Typ); 10591 while Present (Comp) loop 10592 if Nkind (Parent (Comp)) = N_Component_Declaration 10593 and then Present (Expression (Parent (Comp))) 10594 then 10595 exit; 10596 elsif Is_Array_Type (Etype (Comp)) 10597 and then Present (Packed_Array_Impl_Type (Etype (Comp))) 10598 then 10599 Error_Msg_NE 10600 ("\packed array component& " & 10601 "will be initialized to zero??", 10602 Nam, Comp); 10603 exit; 10604 else 10605 Next_Component (Comp); 10606 end if; 10607 end loop; 10608 end; 10609 end if; 10610 10611 Error_Msg_N 10612 ("\use pragma Import for & to " & 10613 "suppress initialization (RM B.1(24))??", 10614 Nam); 10615 end if; 10616 end Warn_Overlay; 10617 10618end Freeze; 10619