1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S E M _ C A T -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1992-2020, 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 Atree; use Atree; 27with Debug; use Debug; 28with Einfo; use Einfo; 29with Elists; use Elists; 30with Errout; use Errout; 31with Lib; use Lib; 32with Namet; use Namet; 33with Nlists; use Nlists; 34with Opt; use Opt; 35with Sem; use Sem; 36with Sem_Attr; use Sem_Attr; 37with Sem_Aux; use Sem_Aux; 38with Sem_Dist; use Sem_Dist; 39with Sem_Eval; use Sem_Eval; 40with Sem_Util; use Sem_Util; 41with Sinfo; use Sinfo; 42with Snames; use Snames; 43with Stand; use Stand; 44 45package body Sem_Cat is 46 47 ----------------------- 48 -- Local Subprograms -- 49 ----------------------- 50 51 procedure Check_Categorization_Dependencies 52 (Unit_Entity : Entity_Id; 53 Depended_Entity : Entity_Id; 54 Info_Node : Node_Id; 55 Is_Subunit : Boolean); 56 -- This procedure checks that the categorization of a lib unit and that 57 -- of the depended unit satisfy dependency restrictions. 58 -- The depended_entity can be the entity in a with_clause item, in which 59 -- case Info_Node denotes that item. The depended_entity can also be the 60 -- parent unit of a child unit, in which case Info_Node is the declaration 61 -- of the child unit. The error message is posted on Info_Node, and is 62 -- specialized if Is_Subunit is true. 63 64 procedure Check_Non_Static_Default_Expr 65 (Type_Def : Node_Id; 66 Obj_Decl : Node_Id); 67 -- Iterate through the component list of a record definition, check 68 -- that no component is declared with a nonstatic default value. 69 -- If a nonstatic default exists, report an error on Obj_Decl. 70 71 function Has_Read_Write_Attributes (E : Entity_Id) return Boolean; 72 -- Return True if entity has attribute definition clauses for Read and 73 -- Write attributes that are visible at some place. 74 75 function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean; 76 -- Returns true if the entity is a type whose full view is a non-remote 77 -- access type, for the purpose of enforcing E.2.2(8) rules. 78 79 function Has_Non_Remote_Access (Typ : Entity_Id) return Boolean; 80 -- Return true if Typ or the type of any of its subcomponents is a non 81 -- remote access type and doesn't have user-defined stream attributes. 82 83 function No_External_Streaming (E : Entity_Id) return Boolean; 84 -- Return True if the entity or one of its subcomponents does not support 85 -- external streaming. 86 87 function In_RCI_Declaration return Boolean; 88 function In_RT_Declaration return Boolean; 89 -- Determine if current scope is within the declaration of a Remote Call 90 -- Interface or Remote Types unit, for semantic checking purposes. 91 92 function In_Package_Declaration return Boolean; 93 -- Shared supporting routine for In_RCI_Declaration and In_RT_Declaration 94 95 function In_Shared_Passive_Unit return Boolean; 96 -- Determines if current scope is within a Shared Passive compilation unit 97 98 function Static_Discriminant_Expr (L : List_Id) return Boolean; 99 -- Iterate through the list of discriminants to check if any of them 100 -- contains non-static default expression, which is a violation in 101 -- a preelaborated library unit. 102 103 procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id); 104 -- Check validity of declaration if RCI or RT unit. It should not contain 105 -- the declaration of an access-to-object type unless it is a general 106 -- access type that designates a class-wide limited private type. There are 107 -- also constraints about the primitive subprograms of the class-wide type. 108 -- RM E.2 (9, 13, 14) 109 110 procedure Validate_RACW_Primitive 111 (Subp : Entity_Id; 112 RACW : Entity_Id); 113 -- Check legality of the declaration of primitive Subp of the designated 114 -- type of the given RACW type. 115 116 --------------------------------------- 117 -- Check_Categorization_Dependencies -- 118 --------------------------------------- 119 120 procedure Check_Categorization_Dependencies 121 (Unit_Entity : Entity_Id; 122 Depended_Entity : Entity_Id; 123 Info_Node : Node_Id; 124 Is_Subunit : Boolean) 125 is 126 N : constant Node_Id := Info_Node; 127 Err : Boolean; 128 129 -- Here we define an enumeration type to represent categorization types, 130 -- ordered so that a unit with a given categorization can only WITH 131 -- units with lower or equal categorization type. 132 133 type Categorization is 134 (Pure, 135 Shared_Passive, 136 Remote_Types, 137 Remote_Call_Interface, 138 Normal); 139 140 function Get_Categorization (E : Entity_Id) return Categorization; 141 -- Check categorization flags from entity, and return in the form 142 -- of the lowest value of the Categorization type that applies to E. 143 144 ------------------------ 145 -- Get_Categorization -- 146 ------------------------ 147 148 function Get_Categorization (E : Entity_Id) return Categorization is 149 begin 150 -- Get the lowest categorization that corresponds to E. Note that 151 -- nothing prevents several (different) categorization pragmas 152 -- to apply to the same library unit, in which case the unit has 153 -- all associated categories, so we need to be careful here to 154 -- check pragmas in proper Categorization order in order to 155 -- return the lowest applicable value. 156 157 -- Ignore Pure specification if set by pragma Pure_Function 158 159 if Is_Pure (E) 160 and then not 161 (Has_Pragma_Pure_Function (E) and not Has_Pragma_Pure (E)) 162 then 163 return Pure; 164 165 elsif Is_Shared_Passive (E) then 166 return Shared_Passive; 167 168 elsif Is_Remote_Types (E) then 169 return Remote_Types; 170 171 elsif Is_Remote_Call_Interface (E) then 172 return Remote_Call_Interface; 173 174 else 175 return Normal; 176 end if; 177 end Get_Categorization; 178 179 Unit_Category : Categorization; 180 With_Category : Categorization; 181 182 -- Start of processing for Check_Categorization_Dependencies 183 184 begin 185 -- Intrinsic subprograms are preelaborated, so do not impose any 186 -- categorization dependencies. Also, ignore categorization 187 -- dependencies when compilation switch -gnatdu is used. 188 189 if Is_Intrinsic_Subprogram (Depended_Entity) or else Debug_Flag_U then 190 return; 191 end if; 192 193 -- First check 10.2.1 (11/1) rules on preelaborate packages 194 195 if Is_Preelaborated (Unit_Entity) 196 and then not Is_Preelaborated (Depended_Entity) 197 and then not Is_Pure (Depended_Entity) 198 then 199 Err := True; 200 else 201 Err := False; 202 end if; 203 204 -- Check categorization rules of RM E.2(5) 205 206 Unit_Category := Get_Categorization (Unit_Entity); 207 With_Category := Get_Categorization (Depended_Entity); 208 209 if With_Category > Unit_Category then 210 211 -- Special case: Remote_Types and Remote_Call_Interface are allowed 212 -- to WITH anything in the package body, per (RM E.2(5)). 213 214 if (Unit_Category = Remote_Types 215 or else Unit_Category = Remote_Call_Interface) 216 and then In_Package_Body (Unit_Entity) 217 then 218 null; 219 220 -- Special case: Remote_Types and Remote_Call_Interface declarations 221 -- can depend on a preelaborated unit via a private with_clause, per 222 -- AI05-0206. 223 224 elsif (Unit_Category = Remote_Types 225 or else 226 Unit_Category = Remote_Call_Interface) 227 and then Nkind (N) = N_With_Clause 228 and then Private_Present (N) 229 and then Is_Preelaborated (Depended_Entity) 230 then 231 null; 232 233 -- All other cases, we do have an error 234 235 else 236 Err := True; 237 end if; 238 end if; 239 240 -- Here if we have an error 241 242 if Err then 243 244 -- These messages are warnings in GNAT mode or if the -gnateP switch 245 -- was set. Otherwise these are real errors for real illegalities. 246 247 -- The reason we suppress these errors in GNAT mode is that the run- 248 -- time has several instances of violations of the categorization 249 -- errors (e.g. Pure units withing Preelaborate units. All these 250 -- violations are harmless in the cases where we intend them, and 251 -- we suppress the warnings with Warnings (Off). In cases where we 252 -- do not intend the violation, warnings are errors in GNAT mode 253 -- anyway, so we will still get an error. 254 255 Error_Msg_Warn := 256 Treat_Categorization_Errors_As_Warnings or GNAT_Mode; 257 258 -- Don't give error if main unit is not an internal unit, and the 259 -- unit generating the message is an internal unit. This is the 260 -- situation in which such messages would be ignored in any case, 261 -- so it is convenient not to generate them (since it causes 262 -- annoying interference with debugging). 263 264 if Is_Internal_Unit (Current_Sem_Unit) 265 and then not Is_Internal_Unit (Main_Unit) 266 then 267 return; 268 269 -- Dependence of Remote_Types or Remote_Call_Interface declaration 270 -- on a preelaborated unit with a normal with_clause. 271 272 elsif (Unit_Category = Remote_Types 273 or else 274 Unit_Category = Remote_Call_Interface) 275 and then Is_Preelaborated (Depended_Entity) 276 then 277 Error_Msg_NE 278 ("<<must use private with clause for preelaborated unit& ", 279 N, Depended_Entity); 280 281 -- Subunit case 282 283 elsif Is_Subunit then 284 Error_Msg_NE 285 ("<subunit cannot depend on& " & 286 "(parent has wrong categorization)", N, Depended_Entity); 287 288 -- Normal unit, not subunit 289 290 else 291 Error_Msg_NE 292 ("<<cannot depend on& " & 293 "(wrong categorization)", N, Depended_Entity); 294 end if; 295 296 -- Add further explanation for Pure/Preelaborate common cases 297 298 if Unit_Category = Pure then 299 Error_Msg_NE 300 ("\<<pure unit cannot depend on non-pure unit", 301 N, Depended_Entity); 302 303 elsif Is_Preelaborated (Unit_Entity) 304 and then not Is_Preelaborated (Depended_Entity) 305 and then not Is_Pure (Depended_Entity) 306 then 307 Error_Msg_NE 308 ("\<<preelaborated unit cannot depend on " 309 & "non-preelaborated unit", 310 N, Depended_Entity); 311 end if; 312 end if; 313 end Check_Categorization_Dependencies; 314 315 ----------------------------------- 316 -- Check_Non_Static_Default_Expr -- 317 ----------------------------------- 318 319 procedure Check_Non_Static_Default_Expr 320 (Type_Def : Node_Id; 321 Obj_Decl : Node_Id) 322 is 323 Recdef : Node_Id; 324 Component_Decl : Node_Id; 325 326 begin 327 if Nkind (Type_Def) = N_Derived_Type_Definition then 328 Recdef := Record_Extension_Part (Type_Def); 329 330 if No (Recdef) then 331 return; 332 end if; 333 334 else 335 Recdef := Type_Def; 336 end if; 337 338 -- Check that component declarations do not involve: 339 340 -- a. a non-static default expression, where the object is 341 -- declared to be default initialized. 342 343 -- b. a dynamic Itype (discriminants and constraints) 344 345 if Null_Present (Recdef) then 346 return; 347 else 348 Component_Decl := First (Component_Items (Component_List (Recdef))); 349 end if; 350 351 while Present (Component_Decl) 352 and then Nkind (Component_Decl) = N_Component_Declaration 353 loop 354 if Present (Expression (Component_Decl)) 355 and then Nkind (Expression (Component_Decl)) /= N_Null 356 and then not Is_OK_Static_Expression (Expression (Component_Decl)) 357 then 358 Error_Msg_Sloc := Sloc (Component_Decl); 359 Error_Msg_F 360 ("object in preelaborated unit has non-static default#", 361 Obj_Decl); 362 363 -- Fix this later ??? 364 365 -- elsif Has_Dynamic_Itype (Component_Decl) then 366 -- Error_Msg_N 367 -- ("dynamic type discriminant," & 368 -- " constraint in preelaborated unit", 369 -- Component_Decl); 370 end if; 371 372 Next (Component_Decl); 373 end loop; 374 end Check_Non_Static_Default_Expr; 375 376 --------------------------- 377 -- Has_Non_Remote_Access -- 378 --------------------------- 379 380 function Has_Non_Remote_Access (Typ : Entity_Id) return Boolean is 381 Component : Entity_Id; 382 Comp_Type : Entity_Id; 383 U_Typ : constant Entity_Id := Underlying_Type (Typ); 384 385 begin 386 if No (U_Typ) then 387 return False; 388 389 elsif Has_Read_Write_Attributes (Typ) 390 or else Has_Read_Write_Attributes (U_Typ) 391 then 392 return False; 393 394 elsif Is_Non_Remote_Access_Type (U_Typ) then 395 return True; 396 end if; 397 398 if Is_Record_Type (U_Typ) then 399 Component := First_Entity (U_Typ); 400 while Present (Component) loop 401 if not Is_Tag (Component) then 402 Comp_Type := Etype (Component); 403 404 if Has_Non_Remote_Access (Comp_Type) then 405 return True; 406 end if; 407 end if; 408 409 Next_Entity (Component); 410 end loop; 411 412 elsif Is_Array_Type (U_Typ) then 413 return Has_Non_Remote_Access (Component_Type (U_Typ)); 414 415 end if; 416 417 return False; 418 end Has_Non_Remote_Access; 419 420 ------------------------------- 421 -- Has_Read_Write_Attributes -- 422 ------------------------------- 423 424 function Has_Read_Write_Attributes (E : Entity_Id) return Boolean is 425 begin 426 return True 427 and then Has_Stream_Attribute_Definition 428 (E, TSS_Stream_Read, At_Any_Place => True) 429 and then Has_Stream_Attribute_Definition 430 (E, TSS_Stream_Write, At_Any_Place => True); 431 end Has_Read_Write_Attributes; 432 433 ------------------------------------- 434 -- Has_Stream_Attribute_Definition -- 435 ------------------------------------- 436 437 function Has_Stream_Attribute_Definition 438 (Typ : Entity_Id; 439 Nam : TSS_Name_Type; 440 At_Any_Place : Boolean := False) return Boolean 441 is 442 Rep_Item : Node_Id; 443 444 Real_Rep : Node_Id; 445 -- The stream operation may be specified by an attribute definition 446 -- clause in the source, or by an aspect that generates such an 447 -- attribute definition. For an aspect, the generated attribute 448 -- definition may be placed at the freeze point of the full view of 449 -- the type, but the aspect specification makes the operation visible 450 -- to a client wherever the partial view is visible. 451 452 begin 453 -- We start from the declaration node and then loop until the end of 454 -- the list until we find the requested attribute definition clause. 455 -- In Ada 2005 mode, clauses are ignored if they are not currently 456 -- visible (this is tested using the corresponding Entity, which is 457 -- inserted by the expander at the point where the clause occurs), 458 -- unless At_Any_Place is true. 459 460 Rep_Item := First_Rep_Item (Typ); 461 while Present (Rep_Item) loop 462 Real_Rep := Rep_Item; 463 464 -- If the representation item is an aspect specification, retrieve 465 -- the corresponding pragma or attribute definition. 466 467 if Nkind (Rep_Item) = N_Aspect_Specification then 468 Real_Rep := Aspect_Rep_Item (Rep_Item); 469 end if; 470 471 if Nkind (Real_Rep) = N_Attribute_Definition_Clause then 472 case Chars (Real_Rep) is 473 when Name_Read => 474 exit when Nam = TSS_Stream_Read; 475 476 when Name_Write => 477 exit when Nam = TSS_Stream_Write; 478 479 when Name_Input => 480 exit when Nam = TSS_Stream_Input; 481 482 when Name_Output => 483 exit when Nam = TSS_Stream_Output; 484 485 when others => 486 null; 487 end case; 488 end if; 489 490 Next_Rep_Item (Rep_Item); 491 end loop; 492 493 -- If not found, and the type is derived from a private view, check 494 -- for a stream attribute inherited from parent. Any specified stream 495 -- attributes will be attached to the derived type's underlying type 496 -- rather the derived type entity itself (which is itself private). 497 498 if No (Rep_Item) 499 and then Is_Private_Type (Typ) 500 and then Is_Derived_Type (Typ) 501 and then Present (Full_View (Typ)) 502 then 503 return Has_Stream_Attribute_Definition 504 (Underlying_Type (Typ), Nam, At_Any_Place); 505 506 -- Otherwise, if At_Any_Place is true, return True if the attribute is 507 -- available at any place; if it is false, return True only if the 508 -- attribute is currently visible. 509 510 else 511 return Present (Rep_Item) 512 and then (Ada_Version < Ada_2005 513 or else At_Any_Place 514 or else not Is_Hidden (Entity (Rep_Item))); 515 end if; 516 end Has_Stream_Attribute_Definition; 517 518 ---------------------------- 519 -- In_Package_Declaration -- 520 ---------------------------- 521 522 function In_Package_Declaration return Boolean is 523 Unit_Kind : constant Node_Kind := 524 Nkind (Unit (Cunit (Current_Sem_Unit))); 525 526 begin 527 -- There are no restrictions on the body of an RCI or RT unit 528 529 return Is_Package_Or_Generic_Package (Current_Scope) 530 and then Unit_Kind /= N_Package_Body 531 and then not In_Package_Body (Current_Scope) 532 and then not In_Instance; 533 end In_Package_Declaration; 534 535 --------------------------- 536 -- In_Preelaborated_Unit -- 537 --------------------------- 538 539 function In_Preelaborated_Unit return Boolean is 540 Unit_Entity : Entity_Id := Current_Scope; 541 Unit_Kind : constant Node_Kind := 542 Nkind (Unit (Cunit (Current_Sem_Unit))); 543 544 begin 545 -- If evaluating actuals for a child unit instantiation, then ignore 546 -- the preelaboration status of the parent; use the child instead. 547 548 if Is_Compilation_Unit (Unit_Entity) 549 and then Unit_Kind in N_Generic_Instantiation 550 and then not In_Same_Source_Unit (Unit_Entity, 551 Cunit (Current_Sem_Unit)) 552 then 553 Unit_Entity := Cunit_Entity (Current_Sem_Unit); 554 end if; 555 556 -- There are no constraints on the body of Remote_Call_Interface or 557 -- Remote_Types packages. 558 559 return (Unit_Entity /= Standard_Standard) 560 and then (Is_Preelaborated (Unit_Entity) 561 or else Is_Pure (Unit_Entity) 562 or else Is_Shared_Passive (Unit_Entity) 563 or else 564 ((Is_Remote_Types (Unit_Entity) 565 or else Is_Remote_Call_Interface (Unit_Entity)) 566 and then Ekind (Unit_Entity) = E_Package 567 and then Unit_Kind /= N_Package_Body 568 and then not In_Package_Body (Unit_Entity) 569 and then not In_Instance)); 570 end In_Preelaborated_Unit; 571 572 ------------------ 573 -- In_Pure_Unit -- 574 ------------------ 575 576 function In_Pure_Unit return Boolean is 577 begin 578 return Is_Pure (Current_Scope); 579 end In_Pure_Unit; 580 581 ------------------------ 582 -- In_RCI_Declaration -- 583 ------------------------ 584 585 function In_RCI_Declaration return Boolean is 586 begin 587 return Is_Remote_Call_Interface (Current_Scope) 588 and then In_Package_Declaration; 589 end In_RCI_Declaration; 590 591 ----------------------- 592 -- In_RT_Declaration -- 593 ----------------------- 594 595 function In_RT_Declaration return Boolean is 596 begin 597 return Is_Remote_Types (Current_Scope) and then In_Package_Declaration; 598 end In_RT_Declaration; 599 600 ---------------------------- 601 -- In_Shared_Passive_Unit -- 602 ---------------------------- 603 604 function In_Shared_Passive_Unit return Boolean is 605 Unit_Entity : constant Entity_Id := Current_Scope; 606 607 begin 608 return Is_Shared_Passive (Unit_Entity); 609 end In_Shared_Passive_Unit; 610 611 --------------------------------------- 612 -- In_Subprogram_Task_Protected_Unit -- 613 --------------------------------------- 614 615 function In_Subprogram_Task_Protected_Unit return Boolean is 616 E : Entity_Id; 617 618 begin 619 -- The following is to verify that a declaration is inside 620 -- subprogram, generic subprogram, task unit, protected unit. 621 -- Used to validate if a lib. unit is Pure. RM 10.2.1(16). 622 623 -- Use scope chain to check successively outer scopes 624 625 E := Current_Scope; 626 loop 627 if Is_Subprogram_Or_Generic_Subprogram (E) 628 or else 629 Is_Concurrent_Type (E) 630 then 631 return True; 632 633 elsif E = Standard_Standard then 634 return False; 635 end if; 636 637 E := Scope (E); 638 end loop; 639 end In_Subprogram_Task_Protected_Unit; 640 641 ------------------------------- 642 -- Is_Non_Remote_Access_Type -- 643 ------------------------------- 644 645 function Is_Non_Remote_Access_Type (E : Entity_Id) return Boolean is 646 U_E : constant Entity_Id := Underlying_Type (Base_Type (E)); 647 -- Use full view of base type to handle subtypes properly. 648 649 begin 650 if No (U_E) then 651 652 -- This case arises for the case of a generic formal type, in which 653 -- case E.2.2(8) rules will be enforced at instantiation time. 654 655 return False; 656 end if; 657 658 return Is_Access_Type (U_E) 659 and then not Is_Remote_Access_To_Class_Wide_Type (U_E) 660 and then not Is_Remote_Access_To_Subprogram_Type (U_E); 661 end Is_Non_Remote_Access_Type; 662 663 --------------------------- 664 -- No_External_Streaming -- 665 --------------------------- 666 667 function No_External_Streaming (E : Entity_Id) return Boolean is 668 U_E : constant Entity_Id := Underlying_Type (E); 669 670 begin 671 if No (U_E) then 672 return False; 673 674 elsif Has_Read_Write_Attributes (E) then 675 676 -- Note: availability of stream attributes is tested on E, not U_E. 677 -- There may be stream attributes defined on U_E that are not visible 678 -- at the place where support of external streaming is tested. 679 680 return False; 681 682 elsif Has_Non_Remote_Access (U_E) then 683 return True; 684 end if; 685 686 return Is_Limited_Type (E); 687 end No_External_Streaming; 688 689 ------------------------------------- 690 -- Set_Categorization_From_Pragmas -- 691 ------------------------------------- 692 693 procedure Set_Categorization_From_Pragmas (N : Node_Id) is 694 P : constant Node_Id := Parent (N); 695 S : constant Entity_Id := Current_Scope; 696 697 procedure Set_Parents (Visibility : Boolean); 698 -- If this is a child instance, the parents are not immediately 699 -- visible during analysis. Make them momentarily visible so that 700 -- the argument of the pragma can be resolved properly, and reset 701 -- afterwards. 702 703 ----------------- 704 -- Set_Parents -- 705 ----------------- 706 707 procedure Set_Parents (Visibility : Boolean) is 708 Par : Entity_Id; 709 begin 710 Par := Scope (S); 711 while Present (Par) and then Par /= Standard_Standard loop 712 Set_Is_Immediately_Visible (Par, Visibility); 713 Par := Scope (Par); 714 end loop; 715 end Set_Parents; 716 717 -- Start of processing for Set_Categorization_From_Pragmas 718 719 begin 720 -- Deal with categorization pragmas in Pragmas of Compilation_Unit. 721 -- The purpose is to set categorization flags before analyzing the 722 -- unit itself, so as to diagnose violations of categorization as 723 -- we process each declaration, even though the pragma appears after 724 -- the unit. This processing is only needed if compilation unit pragmas 725 -- are present. 726 -- Note: This code may be incorrect in the unlikely case a child generic 727 -- unit is instantiated as a child of its (nongeneric) parent, so that 728 -- generic and instance are siblings. 729 730 if Nkind (P) /= N_Compilation_Unit 731 or else No (First (Pragmas_After (Aux_Decls_Node (P)))) 732 then 733 return; 734 end if; 735 736 declare 737 PN : Node_Id; 738 739 begin 740 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then 741 Set_Parents (True); 742 end if; 743 744 PN := First (Pragmas_After (Aux_Decls_Node (P))); 745 while Present (PN) loop 746 747 -- Skip implicit types that may have been introduced by 748 -- previous analysis. 749 750 if Nkind (PN) = N_Pragma then 751 case Get_Pragma_Id (PN) is 752 when Pragma_All_Calls_Remote 753 | Pragma_Preelaborate 754 | Pragma_Pure 755 | Pragma_Remote_Call_Interface 756 | Pragma_Remote_Types 757 | Pragma_Shared_Passive 758 => 759 Analyze (PN); 760 761 when others => 762 null; 763 end case; 764 end if; 765 766 Next (PN); 767 end loop; 768 769 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then 770 Set_Parents (False); 771 end if; 772 end; 773 end Set_Categorization_From_Pragmas; 774 775 ----------------------------------- 776 -- Set_Categorization_From_Scope -- 777 ----------------------------------- 778 779 procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id) is 780 Declaration : Node_Id := Empty; 781 Specification : Node_Id := Empty; 782 783 begin 784 -- Do not modify the purity of an internally generated entity if it has 785 -- been explicitly marked as pure for optimization purposes. 786 787 if not Has_Pragma_Pure_Function (E) then 788 Set_Is_Pure 789 (E, Is_Pure (Scop) and then Is_Library_Level_Entity (E)); 790 end if; 791 792 if not Is_Remote_Call_Interface (E) then 793 if Ekind (E) in Subprogram_Kind then 794 Declaration := Unit_Declaration_Node (E); 795 796 if Nkind (Declaration) in 797 N_Subprogram_Body | N_Subprogram_Renaming_Declaration 798 then 799 Specification := Corresponding_Spec (Declaration); 800 end if; 801 end if; 802 803 -- A subprogram body or renaming-as-body is a remote call interface 804 -- if it serves as the completion of a subprogram declaration that 805 -- is a remote call interface. 806 807 if Nkind (Specification) in N_Entity then 808 Set_Is_Remote_Call_Interface 809 (E, Is_Remote_Call_Interface (Specification)); 810 811 -- A subprogram declaration is a remote call interface when it is 812 -- declared within the visible part of, or declared by, a library 813 -- unit declaration that is a remote call interface. 814 815 else 816 Set_Is_Remote_Call_Interface 817 (E, Is_Remote_Call_Interface (Scop) 818 and then not (In_Private_Part (Scop) 819 or else In_Package_Body (Scop))); 820 end if; 821 end if; 822 823 Set_Is_Remote_Types 824 (E, Is_Remote_Types (Scop) 825 and then not (In_Private_Part (Scop) 826 or else In_Package_Body (Scop))); 827 end Set_Categorization_From_Scope; 828 829 ------------------------------ 830 -- Static_Discriminant_Expr -- 831 ------------------------------ 832 833 -- We need to accommodate a Why_Not_Static call somehow here ??? 834 835 function Static_Discriminant_Expr (L : List_Id) return Boolean is 836 Discriminant_Spec : Node_Id; 837 838 begin 839 Discriminant_Spec := First (L); 840 while Present (Discriminant_Spec) loop 841 if Present (Expression (Discriminant_Spec)) 842 and then 843 not Is_OK_Static_Expression (Expression (Discriminant_Spec)) 844 then 845 return False; 846 end if; 847 848 Next (Discriminant_Spec); 849 end loop; 850 851 return True; 852 end Static_Discriminant_Expr; 853 854 -------------------------------------- 855 -- Validate_Access_Type_Declaration -- 856 -------------------------------------- 857 858 procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id) is 859 Def : constant Node_Id := Type_Definition (N); 860 861 begin 862 case Nkind (Def) is 863 864 -- Access to subprogram case 865 866 when N_Access_To_Subprogram_Definition => 867 868 -- A pure library_item must not contain the declaration of a 869 -- named access type, except within a subprogram, generic 870 -- subprogram, task unit, or protected unit (RM 10.2.1(16)). 871 872 -- This test is skipped in Ada 2005 (see AI-366) 873 874 if Ada_Version < Ada_2005 875 and then Comes_From_Source (T) 876 and then In_Pure_Unit 877 and then not In_Subprogram_Task_Protected_Unit 878 then 879 Error_Msg_N ("named access type not allowed in pure unit", T); 880 end if; 881 882 -- Access to object case 883 884 when N_Access_To_Object_Definition => 885 if Comes_From_Source (T) 886 and then In_Pure_Unit 887 and then not In_Subprogram_Task_Protected_Unit 888 then 889 -- We can't give the message yet, since the type is not frozen 890 -- and in Ada 2005 mode, access types are allowed in pure units 891 -- if the type has no storage pool (see AI-366). So we set a 892 -- flag which will be checked at freeze time. 893 894 Set_Is_Pure_Unit_Access_Type (T); 895 end if; 896 897 -- Check for RCI or RT unit type declaration: declaration of an 898 -- access-to-object type is illegal unless it is a general access 899 -- type that designates a class-wide limited private type. 900 -- Note that constraints on the primitive subprograms of the 901 -- designated tagged type are not enforced here but in 902 -- Validate_RACW_Primitives, which is done separately because the 903 -- designated type might not be frozen (and therefore its 904 -- primitive operations might not be completely known) at the 905 -- point of the RACW declaration. 906 907 Validate_Remote_Access_Object_Type_Declaration (T); 908 909 -- Check for shared passive unit type declaration. It should 910 -- not contain the declaration of access to class wide type, 911 -- access to task type and access to protected type with entry. 912 913 Validate_SP_Access_Object_Type_Decl (T); 914 915 when others => 916 null; 917 end case; 918 919 -- Set categorization flag from package on entity as well, to allow 920 -- easy checks later on for required validations of RCI or RT units. 921 -- This is only done for entities that are in the original source. 922 923 if Comes_From_Source (T) 924 and then not (In_Package_Body (Scope (T)) 925 or else In_Private_Part (Scope (T))) 926 then 927 Set_Is_Remote_Call_Interface 928 (T, Is_Remote_Call_Interface (Scope (T))); 929 Set_Is_Remote_Types 930 (T, Is_Remote_Types (Scope (T))); 931 end if; 932 end Validate_Access_Type_Declaration; 933 934 ---------------------------- 935 -- Validate_Ancestor_Part -- 936 ---------------------------- 937 938 procedure Validate_Ancestor_Part (N : Node_Id) is 939 A : constant Node_Id := Ancestor_Part (N); 940 T : constant Entity_Id := Entity (A); 941 942 begin 943 if In_Preelaborated_Unit 944 and then not In_Subprogram_Or_Concurrent_Unit 945 and then (not Inside_A_Generic 946 or else Present (Enclosing_Generic_Body (N))) 947 then 948 -- If the type is private, it must have the Ada 2005 pragma 949 -- Has_Preelaborable_Initialization. 950 951 -- The check is omitted within predefined units. This is probably 952 -- obsolete code to fix the Ada 95 weakness in this area ??? 953 954 if Is_Private_Type (T) 955 and then not Has_Pragma_Preelab_Init (T) 956 and then not In_Internal_Unit (N) 957 then 958 Error_Msg_N 959 ("private ancestor type not allowed in preelaborated unit", A); 960 961 elsif Is_Record_Type (T) then 962 if Nkind (Parent (T)) = N_Full_Type_Declaration then 963 Check_Non_Static_Default_Expr 964 (Type_Definition (Parent (T)), A); 965 end if; 966 end if; 967 end if; 968 end Validate_Ancestor_Part; 969 970 ---------------------------------------- 971 -- Validate_Categorization_Dependency -- 972 ---------------------------------------- 973 974 procedure Validate_Categorization_Dependency 975 (N : Node_Id; 976 E : Entity_Id) 977 is 978 K : constant Node_Kind := Nkind (N); 979 P : Node_Id := Parent (N); 980 U : Entity_Id := E; 981 Is_Subunit : constant Boolean := Nkind (P) = N_Subunit; 982 983 begin 984 -- Only validate library units and subunits. For subunits, checks 985 -- concerning withed units apply to the parent compilation unit. 986 987 if Is_Subunit then 988 P := Parent (P); 989 U := Scope (E); 990 991 while Present (U) 992 and then not Is_Compilation_Unit (U) 993 and then not Is_Child_Unit (U) 994 loop 995 U := Scope (U); 996 end loop; 997 end if; 998 999 if Nkind (P) /= N_Compilation_Unit then 1000 return; 1001 end if; 1002 1003 -- Body of RCI unit does not need validation 1004 1005 if Is_Remote_Call_Interface (E) 1006 and then Nkind (N) in N_Package_Body | N_Subprogram_Body 1007 then 1008 return; 1009 end if; 1010 1011 -- Ada 2005 (AI-50217): Process explicit non-limited with_clauses 1012 1013 declare 1014 Item : Node_Id; 1015 Entity_Of_Withed : Entity_Id; 1016 1017 begin 1018 Item := First (Context_Items (P)); 1019 while Present (Item) loop 1020 if Nkind (Item) = N_With_Clause 1021 and then 1022 not (Implicit_With (Item) 1023 or else Limited_Present (Item) 1024 1025 -- Skip if error already posted on the WITH clause (in 1026 -- which case the Name attribute may be invalid). In 1027 -- particular, this fixes the problem of hanging in the 1028 -- presence of a WITH clause on a child that is an 1029 -- illegal generic instantiation. 1030 1031 or else Error_Posted (Item)) 1032 and then 1033 not (Try_Semantics 1034 1035 -- Skip processing malformed trees 1036 1037 and then Nkind (Name (Item)) not in N_Has_Entity) 1038 then 1039 Entity_Of_Withed := Entity (Name (Item)); 1040 Check_Categorization_Dependencies 1041 (U, Entity_Of_Withed, Item, Is_Subunit); 1042 end if; 1043 1044 Next (Item); 1045 end loop; 1046 end; 1047 1048 -- Child depends on parent; therefore parent should also be categorized 1049 -- and satisfy the dependency hierarchy. 1050 1051 -- Check if N is a child spec 1052 1053 if (K in N_Generic_Declaration or else 1054 K in N_Generic_Instantiation or else 1055 K in N_Generic_Renaming_Declaration or else 1056 K = N_Package_Declaration or else 1057 K = N_Package_Renaming_Declaration or else 1058 K = N_Subprogram_Declaration or else 1059 K = N_Subprogram_Renaming_Declaration) 1060 and then Present (Parent_Spec (N)) 1061 then 1062 Check_Categorization_Dependencies (E, Scope (E), N, False); 1063 1064 -- Verify that public child of an RCI library unit must also be an 1065 -- RCI library unit (RM E.2.3(15)). 1066 1067 if Is_Remote_Call_Interface (Scope (E)) 1068 and then not Private_Present (P) 1069 and then not Is_Remote_Call_Interface (E) 1070 then 1071 Error_Msg_N 1072 ("public child of 'R'C'I unit must also be 'R'C'I unit", N); 1073 end if; 1074 end if; 1075 end Validate_Categorization_Dependency; 1076 1077 -------------------------------- 1078 -- Validate_Controlled_Object -- 1079 -------------------------------- 1080 1081 procedure Validate_Controlled_Object (E : Entity_Id) is 1082 begin 1083 -- Don't need this check in Ada 2005 mode, where this is all taken 1084 -- care of by the mechanism for Preelaborable Initialization. 1085 1086 if Ada_Version >= Ada_2005 then 1087 return; 1088 end if; 1089 1090 -- For now, never apply this check for internal GNAT units, since we 1091 -- have a number of cases in the library where we are stuck with objects 1092 -- of this type, and the RM requires Preelaborate. 1093 1094 -- For similar reasons, we only do this check for source entities, since 1095 -- we generate entities of this type in some situations. 1096 1097 -- Note that the 10.2.1(9) restrictions are not relevant to us anyway. 1098 -- We have to enforce them for RM compatibility, but we have no trouble 1099 -- accepting these objects and doing the right thing. Note that there is 1100 -- no requirement that Preelaborate not actually generate any code. 1101 1102 if In_Preelaborated_Unit 1103 and then not Debug_Flag_PP 1104 and then Comes_From_Source (E) 1105 and then not In_Internal_Unit (E) 1106 and then (not Inside_A_Generic 1107 or else Present (Enclosing_Generic_Body (E))) 1108 and then not Is_Protected_Type (Etype (E)) 1109 then 1110 Error_Msg_N 1111 ("library level controlled object not allowed in " & 1112 "preelaborated unit", E); 1113 end if; 1114 end Validate_Controlled_Object; 1115 1116 -------------------------------------- 1117 -- Validate_Null_Statement_Sequence -- 1118 -------------------------------------- 1119 1120 procedure Validate_Null_Statement_Sequence (N : Node_Id) is 1121 Item : Node_Id; 1122 1123 begin 1124 if In_Preelaborated_Unit then 1125 Item := First (Statements (Handled_Statement_Sequence (N))); 1126 while Present (Item) loop 1127 if Nkind (Item) /= N_Label 1128 and then Nkind (Item) /= N_Null_Statement 1129 then 1130 -- In GNAT mode, this is a warning, allowing the run-time 1131 -- to judiciously bypass this error condition. 1132 1133 Error_Msg_Warn := GNAT_Mode; 1134 Error_Msg_N 1135 ("<<statements not allowed in preelaborated unit", Item); 1136 1137 exit; 1138 end if; 1139 1140 Next (Item); 1141 end loop; 1142 end if; 1143 end Validate_Null_Statement_Sequence; 1144 1145 --------------------------------- 1146 -- Validate_Object_Declaration -- 1147 --------------------------------- 1148 1149 procedure Validate_Object_Declaration (N : Node_Id) is 1150 Id : constant Entity_Id := Defining_Identifier (N); 1151 E : constant Node_Id := Expression (N); 1152 Odf : constant Node_Id := Object_Definition (N); 1153 T : constant Entity_Id := Etype (Id); 1154 1155 begin 1156 -- Verify that any access to subprogram object does not have in its 1157 -- subprogram profile access type parameters or limited parameters 1158 -- without Read and Write attributes (E.2.3(13)). 1159 1160 Validate_RCI_Subprogram_Declaration (N); 1161 1162 -- Check that if we are in preelaborated elaboration code, then we 1163 -- do not have an instance of a default initialized private, task or 1164 -- protected object declaration which would violate (RM 10.2.1(9)). 1165 -- Note that constants are never default initialized (and the test 1166 -- below also filters out deferred constants). A variable is default 1167 -- initialized if it does *not* have an initialization expression. 1168 1169 -- Filter out cases that are not declaration of a variable from source 1170 1171 if Nkind (N) /= N_Object_Declaration 1172 or else Constant_Present (N) 1173 or else not Comes_From_Source (Id) 1174 then 1175 return; 1176 end if; 1177 1178 -- Exclude generic specs from the checks (this will get rechecked 1179 -- on instantiations). 1180 1181 if Inside_A_Generic and then No (Enclosing_Generic_Body (Id)) then 1182 return; 1183 end if; 1184 1185 -- Required checks for declaration that is in a preelaborated package 1186 -- and is not within some subprogram. 1187 1188 if In_Preelaborated_Unit 1189 and then not In_Subprogram_Or_Concurrent_Unit 1190 then 1191 -- Check for default initialized variable case. Note that in 1192 -- accordance with (RM B.1(24)) imported objects are not subject to 1193 -- default initialization. 1194 -- If the initialization does not come from source and is an 1195 -- aggregate, it is a static initialization that replaces an 1196 -- implicit call, and must be treated as such. 1197 1198 if Present (E) 1199 and then (Comes_From_Source (E) or else Nkind (E) /= N_Aggregate) 1200 then 1201 null; 1202 1203 elsif Is_Imported (Id) then 1204 null; 1205 1206 else 1207 declare 1208 Ent : Entity_Id := T; 1209 1210 begin 1211 -- An array whose component type is a record with nonstatic 1212 -- default expressions is a violation, so we get the array's 1213 -- component type. 1214 1215 if Is_Array_Type (Ent) then 1216 declare 1217 Comp_Type : Entity_Id; 1218 1219 begin 1220 Comp_Type := Component_Type (Ent); 1221 while Is_Array_Type (Comp_Type) loop 1222 Comp_Type := Component_Type (Comp_Type); 1223 end loop; 1224 1225 Ent := Comp_Type; 1226 end; 1227 end if; 1228 1229 -- Object decl. that is of record type and has no default expr. 1230 -- should check if there is any non-static default expression 1231 -- in component decl. of the record type decl. 1232 1233 if Is_Record_Type (Ent) then 1234 if Nkind (Parent (Ent)) = N_Full_Type_Declaration then 1235 Check_Non_Static_Default_Expr 1236 (Type_Definition (Parent (Ent)), N); 1237 1238 elsif Nkind (Odf) = N_Subtype_Indication 1239 and then not Is_Array_Type (T) 1240 and then not Is_Private_Type (T) 1241 then 1242 Check_Non_Static_Default_Expr (Type_Definition 1243 (Parent (Entity (Subtype_Mark (Odf)))), N); 1244 end if; 1245 end if; 1246 1247 -- Check for invalid use of private object. Note that Ada 2005 1248 -- AI-161 modifies the rules for Ada 2005, including the use of 1249 -- the new pragma Preelaborable_Initialization. 1250 1251 if Is_Private_Type (Ent) 1252 or else Depends_On_Private (Ent) 1253 then 1254 -- Case where type has preelaborable initialization which 1255 -- means that a pragma Preelaborable_Initialization was 1256 -- given for the private type. 1257 1258 if Relaxed_RM_Semantics then 1259 1260 -- In relaxed mode, do not issue these messages, this 1261 -- is basically similar to the GNAT_Mode test below. 1262 1263 null; 1264 1265 elsif Has_Preelaborable_Initialization (Ent) then 1266 1267 -- But for the predefined units, we will ignore this 1268 -- status unless we are in Ada 2005 mode since we want 1269 -- Ada 95 compatible behavior, in which the entities 1270 -- marked with this pragma in the predefined library are 1271 -- not treated specially. 1272 1273 if Ada_Version < Ada_2005 then 1274 Error_Msg_N 1275 ("private object not allowed in preelaborated unit", 1276 N); 1277 Error_Msg_N ("\(would be legal in Ada 2005 mode)", N); 1278 end if; 1279 1280 -- Type does not have preelaborable initialization 1281 1282 else 1283 -- We allow this when compiling in GNAT mode to make life 1284 -- easier for some cases where it would otherwise be hard 1285 -- to be exactly valid Ada. 1286 1287 if not GNAT_Mode then 1288 Error_Msg_N 1289 ("private object not allowed in preelaborated unit", 1290 N); 1291 1292 -- Add a message if it would help to provide a pragma 1293 -- Preelaborable_Initialization on the type of the 1294 -- object (which would make it legal in Ada 2005). 1295 1296 -- If the type has no full view (generic type, or 1297 -- previous error), the warning does not apply. 1298 1299 if Is_Private_Type (Ent) 1300 and then Present (Full_View (Ent)) 1301 and then 1302 Has_Preelaborable_Initialization (Full_View (Ent)) 1303 then 1304 Error_Msg_Sloc := Sloc (Ent); 1305 1306 if Ada_Version >= Ada_2005 then 1307 Error_Msg_NE 1308 ("\would be legal if pragma Preelaborable_" & 1309 "Initialization given for & #", N, Ent); 1310 else 1311 Error_Msg_NE 1312 ("\would be legal in Ada 2005 if pragma " & 1313 "Preelaborable_Initialization given for & #", 1314 N, Ent); 1315 end if; 1316 end if; 1317 end if; 1318 end if; 1319 1320 -- Access to Task or Protected type 1321 1322 elsif Is_Entity_Name (Odf) 1323 and then Present (Etype (Odf)) 1324 and then Is_Access_Type (Etype (Odf)) 1325 then 1326 Ent := Designated_Type (Etype (Odf)); 1327 1328 elsif Is_Entity_Name (Odf) then 1329 Ent := Entity (Odf); 1330 1331 elsif Nkind (Odf) = N_Subtype_Indication then 1332 Ent := Etype (Subtype_Mark (Odf)); 1333 1334 elsif Nkind (Odf) = N_Constrained_Array_Definition then 1335 Ent := Component_Type (T); 1336 end if; 1337 1338 if Is_Task_Type (Ent) 1339 or else (Is_Protected_Type (Ent) and then Has_Entries (Ent)) 1340 then 1341 Error_Msg_N 1342 ("concurrent object not allowed in preelaborated unit", 1343 N); 1344 return; 1345 end if; 1346 end; 1347 end if; 1348 1349 -- Non-static discriminants not allowed in preelaborated unit. 1350 -- Objects of a controlled type with a user-defined Initialize 1351 -- are forbidden as well. 1352 1353 if Is_Record_Type (Etype (Id)) then 1354 declare 1355 ET : constant Entity_Id := Etype (Id); 1356 EE : constant Entity_Id := Etype (Etype (Id)); 1357 PEE : Node_Id; 1358 1359 begin 1360 if Has_Discriminants (ET) and then Present (EE) then 1361 PEE := Parent (EE); 1362 1363 if Nkind (PEE) = N_Full_Type_Declaration 1364 and then not Static_Discriminant_Expr 1365 (Discriminant_Specifications (PEE)) 1366 then 1367 Error_Msg_N 1368 ("non-static discriminant in preelaborated unit", 1369 PEE); 1370 end if; 1371 end if; 1372 1373 -- For controlled type or type with controlled component, check 1374 -- preelaboration flag, as there may be a non-null Initialize 1375 -- primitive. For language versions earlier than Ada 2005, 1376 -- there is no notion of preelaborable initialization, and 1377 -- Validate_Controlled_Object is used to enforce rules for 1378 -- controlled objects. 1379 1380 if (Is_Controlled (ET) or else Has_Controlled_Component (ET)) 1381 and then Ada_Version >= Ada_2005 1382 and then not Has_Preelaborable_Initialization (ET) 1383 then 1384 Error_Msg_NE 1385 ("controlled type& does not have" 1386 & " preelaborable initialization", N, ET); 1387 end if; 1388 end; 1389 1390 end if; 1391 end if; 1392 1393 -- A pure library_item must not contain the declaration of any variable 1394 -- except within a subprogram, generic subprogram, task unit, or 1395 -- protected unit (RM 10.2.1(16)). 1396 1397 if In_Pure_Unit and then not In_Subprogram_Task_Protected_Unit then 1398 Error_Msg_N ("declaration of variable not allowed in pure unit", N); 1399 1400 elsif not In_Private_Part (Id) then 1401 1402 -- The visible part of an RCI library unit must not contain the 1403 -- declaration of a variable (RM E.1.3(9)). 1404 1405 if In_RCI_Declaration then 1406 Error_Msg_N ("visible variable not allowed in 'R'C'I unit", N); 1407 1408 -- The visible part of a Shared Passive library unit must not contain 1409 -- the declaration of a variable (RM E.2.2(7)). 1410 1411 elsif In_RT_Declaration then 1412 Error_Msg_N 1413 ("visible variable not allowed in remote types unit", N); 1414 end if; 1415 end if; 1416 end Validate_Object_Declaration; 1417 1418 ----------------------------- 1419 -- Validate_RACW_Primitive -- 1420 ----------------------------- 1421 1422 procedure Validate_RACW_Primitive 1423 (Subp : Entity_Id; 1424 RACW : Entity_Id) 1425 is 1426 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id); 1427 -- Diagnose illegality on N. If RACW is present, report the error on it 1428 -- rather than on N. 1429 1430 ------------------------- 1431 -- Illegal_Remote_Subp -- 1432 ------------------------- 1433 1434 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id) is 1435 begin 1436 if Present (RACW) then 1437 if not Error_Posted (RACW) then 1438 Error_Msg_N 1439 ("illegal remote access to class-wide type&", RACW); 1440 end if; 1441 1442 Error_Msg_Sloc := Sloc (N); 1443 Error_Msg_NE ("\\" & Msg & " in primitive& #", RACW, Subp); 1444 1445 else 1446 Error_Msg_NE (Msg & " in remote subprogram&", N, Subp); 1447 end if; 1448 end Illegal_Remote_Subp; 1449 1450 Rtyp : Entity_Id; 1451 Param : Node_Id; 1452 Param_Spec : Node_Id; 1453 Param_Type : Entity_Id; 1454 1455 -- Start of processing for Validate_RACW_Primitive 1456 1457 begin 1458 -- Check return type 1459 1460 if Ekind (Subp) = E_Function then 1461 Rtyp := Etype (Subp); 1462 1463 -- AI05-0101 (Binding Interpretation): The result type of a remote 1464 -- function must either support external streaming or be a 1465 -- controlling access result type. 1466 1467 if Has_Controlling_Result (Subp) then 1468 null; 1469 1470 elsif Ekind (Rtyp) = E_Anonymous_Access_Type then 1471 Illegal_Remote_Subp ("anonymous access result", Rtyp); 1472 1473 elsif Is_Limited_Type (Rtyp) then 1474 if No (TSS (Rtyp, TSS_Stream_Read)) 1475 or else 1476 No (TSS (Rtyp, TSS_Stream_Write)) 1477 then 1478 Illegal_Remote_Subp 1479 ("limited return type must have Read and Write attributes", 1480 Parent (Subp)); 1481 Explain_Limited_Type (Rtyp, Parent (Subp)); 1482 end if; 1483 1484 -- Check that the return type supports external streaming 1485 1486 elsif No_External_Streaming (Rtyp) 1487 and then not Error_Posted (Rtyp) 1488 then 1489 Illegal_Remote_Subp ("return type containing non-remote access " 1490 & "must have Read and Write attributes", 1491 Parent (Subp)); 1492 end if; 1493 end if; 1494 1495 Param := First_Formal (Subp); 1496 while Present (Param) loop 1497 1498 -- Now find out if this parameter is a controlling parameter 1499 1500 Param_Spec := Parent (Param); 1501 Param_Type := Etype (Param); 1502 1503 if Is_Controlling_Formal (Param) then 1504 1505 -- It is a controlling parameter, so specific checks below do not 1506 -- apply. 1507 1508 null; 1509 1510 elsif Ekind (Param_Type) in E_Anonymous_Access_Type 1511 | E_Anonymous_Access_Subprogram_Type 1512 then 1513 -- From RM E.2.2(14), no anonymous access parameter other than 1514 -- controlling ones may be used (because an anonymous access 1515 -- type never supports external streaming). 1516 1517 Illegal_Remote_Subp 1518 ("non-controlling access parameter", Param_Spec); 1519 1520 elsif No_External_Streaming (Param_Type) 1521 and then not Error_Posted (Param_Type) 1522 then 1523 Illegal_Remote_Subp ("formal parameter in remote subprogram must " 1524 & "support external streaming", Param_Spec); 1525 end if; 1526 1527 -- Check next parameter in this subprogram 1528 1529 Next_Formal (Param); 1530 end loop; 1531 end Validate_RACW_Primitive; 1532 1533 ------------------------------ 1534 -- Validate_RACW_Primitives -- 1535 ------------------------------ 1536 1537 procedure Validate_RACW_Primitives (T : Entity_Id) is 1538 Desig_Type : Entity_Id; 1539 Primitive_Subprograms : Elist_Id; 1540 Subprogram_Elmt : Elmt_Id; 1541 Subprogram : Entity_Id; 1542 1543 begin 1544 Desig_Type := Etype (Designated_Type (T)); 1545 1546 -- No action needed for concurrent types 1547 1548 if Is_Concurrent_Type (Desig_Type) then 1549 return; 1550 end if; 1551 1552 Primitive_Subprograms := Primitive_Operations (Desig_Type); 1553 1554 Subprogram_Elmt := First_Elmt (Primitive_Subprograms); 1555 while Subprogram_Elmt /= No_Elmt loop 1556 Subprogram := Node (Subprogram_Elmt); 1557 1558 if Is_Predefined_Dispatching_Operation (Subprogram) 1559 or else Is_Hidden (Subprogram) 1560 then 1561 goto Next_Subprogram; 1562 end if; 1563 1564 Validate_RACW_Primitive (Subp => Subprogram, RACW => T); 1565 1566 <<Next_Subprogram>> 1567 Next_Elmt (Subprogram_Elmt); 1568 end loop; 1569 end Validate_RACW_Primitives; 1570 1571 ------------------------------- 1572 -- Validate_RCI_Declarations -- 1573 ------------------------------- 1574 1575 procedure Validate_RCI_Declarations (P : Entity_Id) is 1576 E : Entity_Id; 1577 1578 begin 1579 E := First_Entity (P); 1580 while Present (E) loop 1581 if Comes_From_Source (E) then 1582 if Is_Limited_Type (E) then 1583 Error_Msg_N 1584 ("limited type not allowed in 'R'C'I unit", Parent (E)); 1585 Explain_Limited_Type (E, Parent (E)); 1586 1587 elsif Ekind (E) in E_Generic_Function 1588 | E_Generic_Package 1589 | E_Generic_Procedure 1590 then 1591 Error_Msg_N ("generic declaration not allowed in 'R'C'I unit", 1592 Parent (E)); 1593 1594 elsif (Ekind (E) = E_Function or else Ekind (E) = E_Procedure) 1595 and then Has_Pragma_Inline (E) 1596 then 1597 Error_Msg_N 1598 ("inlined subprogram not allowed in 'R'C'I unit", Parent (E)); 1599 1600 -- Inner packages that are renamings need not be checked. Generic 1601 -- RCI packages are subject to the checks, but entities that come 1602 -- from formal packages are not part of the visible declarations 1603 -- of the package and are not checked. 1604 1605 elsif Ekind (E) = E_Package then 1606 if Present (Renamed_Entity (E)) then 1607 null; 1608 1609 elsif Ekind (P) /= E_Generic_Package 1610 or else List_Containing (Unit_Declaration_Node (E)) /= 1611 Generic_Formal_Declarations 1612 (Unit_Declaration_Node (P)) 1613 then 1614 Validate_RCI_Declarations (E); 1615 end if; 1616 end if; 1617 end if; 1618 1619 Next_Entity (E); 1620 end loop; 1621 end Validate_RCI_Declarations; 1622 1623 ----------------------------------------- 1624 -- Validate_RCI_Subprogram_Declaration -- 1625 ----------------------------------------- 1626 1627 procedure Validate_RCI_Subprogram_Declaration (N : Node_Id) is 1628 K : constant Node_Kind := Nkind (N); 1629 Profile : List_Id; 1630 Id : constant Entity_Id := Defining_Entity (N); 1631 Param_Spec : Node_Id; 1632 Param_Type : Entity_Id; 1633 Error_Node : Node_Id := N; 1634 1635 begin 1636 -- This procedure enforces rules on subprogram and access to subprogram 1637 -- declarations in RCI units. These rules do not apply to expander 1638 -- generated routines, which are not remote subprograms. It is called: 1639 1640 -- 1. from Analyze_Subprogram_Declaration. 1641 -- 2. from Validate_Object_Declaration (access to subprogram). 1642 1643 if not (Comes_From_Source (N) 1644 and then In_RCI_Declaration 1645 and then not In_Private_Part (Scope (Id))) 1646 then 1647 return; 1648 end if; 1649 1650 if K = N_Subprogram_Declaration then 1651 Profile := Parameter_Specifications (Specification (N)); 1652 1653 else 1654 pragma Assert (K = N_Object_Declaration); 1655 1656 -- The above assertion is dubious, the visible declarations of an 1657 -- RCI unit never contain an object declaration, this should be an 1658 -- ACCESS-to-object declaration??? 1659 1660 if Nkind (Id) = N_Defining_Identifier 1661 and then Nkind (Parent (Etype (Id))) = N_Full_Type_Declaration 1662 and then Ekind (Etype (Id)) = E_Access_Subprogram_Type 1663 then 1664 Profile := 1665 Parameter_Specifications (Type_Definition (Parent (Etype (Id)))); 1666 else 1667 return; 1668 end if; 1669 end if; 1670 1671 -- Iterate through the parameter specification list, checking that 1672 -- no access parameter and no limited type parameter in the list. 1673 -- RM E.2.3(14). 1674 1675 if Present (Profile) then 1676 Param_Spec := First (Profile); 1677 while Present (Param_Spec) loop 1678 Param_Type := Etype (Defining_Identifier (Param_Spec)); 1679 1680 if Ekind (Param_Type) = E_Anonymous_Access_Type then 1681 if K = N_Subprogram_Declaration then 1682 Error_Node := Param_Spec; 1683 end if; 1684 1685 -- Report error only if declaration is in source program 1686 1687 if Comes_From_Source (Id) then 1688 Error_Msg_N 1689 ("subprogram in 'R'C'I unit cannot have access parameter", 1690 Error_Node); 1691 end if; 1692 1693 -- For a limited private type parameter, we check only the private 1694 -- declaration and ignore full type declaration, unless this is 1695 -- the only declaration for the type, e.g., as a limited record. 1696 1697 elsif No_External_Streaming (Param_Type) then 1698 if K = N_Subprogram_Declaration then 1699 Error_Node := Param_Spec; 1700 end if; 1701 1702 Error_Msg_NE 1703 ("formal of remote subprogram& " 1704 & "must support external streaming", 1705 Error_Node, Id); 1706 if Is_Limited_Type (Param_Type) then 1707 Explain_Limited_Type (Param_Type, Error_Node); 1708 end if; 1709 end if; 1710 1711 Next (Param_Spec); 1712 end loop; 1713 end if; 1714 1715 if Ekind (Id) = E_Function 1716 and then Ekind (Etype (Id)) = E_Anonymous_Access_Type 1717 and then Comes_From_Source (Id) 1718 then 1719 Error_Msg_N 1720 ("function in 'R'C'I unit cannot have access result", 1721 Error_Node); 1722 end if; 1723 end Validate_RCI_Subprogram_Declaration; 1724 1725 ---------------------------------------------------- 1726 -- Validate_Remote_Access_Object_Type_Declaration -- 1727 ---------------------------------------------------- 1728 1729 procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id) is 1730 Direct_Designated_Type : Entity_Id; 1731 Desig_Type : Entity_Id; 1732 1733 begin 1734 -- We are called from Analyze_Full_Type_Declaration, and the Nkind of 1735 -- the given node is N_Access_To_Object_Definition. 1736 1737 if not Comes_From_Source (T) 1738 or else (not In_RCI_Declaration and then not In_RT_Declaration) 1739 then 1740 return; 1741 end if; 1742 1743 -- An access definition in the private part of a package is not a 1744 -- remote access type. Restrictions related to external streaming 1745 -- support for non-remote access types are enforced elsewhere. Note 1746 -- that In_Private_Part is never set on type entities: check flag 1747 -- on enclosing scope. 1748 1749 if In_Private_Part (Scope (T)) then 1750 return; 1751 end if; 1752 1753 -- Check RCI or RT unit type declaration. It may not contain the 1754 -- declaration of an access-to-object type unless it is a general access 1755 -- type that designates a class-wide limited private type or subtype. 1756 -- There are also constraints on the primitive subprograms of the 1757 -- class-wide type (RM E.2.2(14), see Validate_RACW_Primitives). 1758 1759 if Ekind (T) /= E_General_Access_Type 1760 or else not Is_Class_Wide_Type (Designated_Type (T)) 1761 then 1762 if In_RCI_Declaration then 1763 Error_Msg_N 1764 ("error in access type in Remote_Call_Interface unit", T); 1765 else 1766 Error_Msg_N 1767 ("error in access type in Remote_Types unit", T); 1768 end if; 1769 1770 Error_Msg_N ("\must be general access to class-wide type", T); 1771 return; 1772 end if; 1773 1774 Direct_Designated_Type := Designated_Type (T); 1775 Desig_Type := Etype (Direct_Designated_Type); 1776 1777 -- Why is this check not in Validate_Remote_Access_To_Class_Wide_Type??? 1778 1779 if not Is_Valid_Remote_Object_Type (Desig_Type) then 1780 Error_Msg_N 1781 ("error in designated type of remote access to class-wide type", T); 1782 Error_Msg_N 1783 ("\must be tagged limited private or private extension", T); 1784 return; 1785 end if; 1786 end Validate_Remote_Access_Object_Type_Declaration; 1787 1788 ----------------------------------------------- 1789 -- Validate_Remote_Access_To_Class_Wide_Type -- 1790 ----------------------------------------------- 1791 1792 procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id) is 1793 K : constant Node_Kind := Nkind (N); 1794 PK : constant Node_Kind := Nkind (Parent (N)); 1795 E : Entity_Id; 1796 1797 begin 1798 -- This subprogram enforces the checks in (RM E.2.2(8)) for certain uses 1799 -- of class-wide limited private types. 1800 1801 -- Storage_Pool and Storage_Size are not defined for such types 1802 -- 1803 -- The expected type of allocator must not be such a type. 1804 1805 -- The actual parameter of generic instantiation must not be such a 1806 -- type if the formal parameter is of an access type. 1807 1808 -- On entry, there are several cases: 1809 1810 -- 1. called from sem_attr Analyze_Attribute where attribute name is 1811 -- either Storage_Pool or Storage_Size. 1812 1813 -- 2. called from exp_ch4 Expand_N_Allocator 1814 1815 -- 3. called from sem_ch4 Analyze_Explicit_Dereference 1816 1817 -- 4. called from sem_res Resolve_Actuals 1818 1819 if K = N_Attribute_Definition_Clause then 1820 E := Etype (Entity (N)); 1821 1822 if Is_Remote_Access_To_Class_Wide_Type (E) then 1823 Error_Msg_Name_1 := Chars (N); 1824 Error_Msg_N 1825 ("cannot specify% aspect for a remote operand", N); 1826 return; 1827 end if; 1828 1829 elsif K = N_Attribute_Reference then 1830 E := Etype (Prefix (N)); 1831 1832 if Is_Remote_Access_To_Class_Wide_Type (E) then 1833 Error_Msg_N ("incorrect attribute of remote operand", N); 1834 return; 1835 end if; 1836 1837 elsif K = N_Allocator then 1838 E := Etype (N); 1839 1840 if Is_Remote_Access_To_Class_Wide_Type (E) then 1841 Error_Msg_N ("incorrect expected remote type of allocator", N); 1842 return; 1843 end if; 1844 1845 -- This subprogram also enforces the checks in E.2.2(13). A value of 1846 -- such type must not be dereferenced unless as controlling operand of 1847 -- a dispatching call. Explicit dereferences not coming from source are 1848 -- exempted from this checking because the expander produces them in 1849 -- some cases (such as for tag checks on dispatching calls with multiple 1850 -- controlling operands). However we do check in the case of an implicit 1851 -- dereference that is expanded to an explicit dereference (hence the 1852 -- test of whether Original_Node (N) comes from source). 1853 1854 elsif K = N_Explicit_Dereference 1855 and then Comes_From_Source (Original_Node (N)) 1856 then 1857 E := Etype (Prefix (N)); 1858 1859 -- If the class-wide type is not a remote one, the restrictions 1860 -- do not apply. 1861 1862 if not Is_Remote_Access_To_Class_Wide_Type (E) then 1863 return; 1864 end if; 1865 1866 -- If we have a true dereference that comes from source and that 1867 -- is a controlling argument for a dispatching call, accept it. 1868 1869 if Is_Actual_Parameter (N) and then Is_Controlling_Actual (N) then 1870 return; 1871 end if; 1872 1873 -- If we are just within a procedure or function call and the 1874 -- dereference has not been analyzed, return because this procedure 1875 -- will be called again from sem_res Resolve_Actuals. The same can 1876 -- apply in the case of dereference that is the prefix of a selected 1877 -- component, which can be a call given in prefixed form. 1878 1879 if (Is_Actual_Parameter (N) or else PK = N_Selected_Component) 1880 and then not Analyzed (N) 1881 then 1882 return; 1883 end if; 1884 1885 -- We must allow expanded code to generate a reference to the tag of 1886 -- the designated object (may be either the actual tag, or the stub 1887 -- tag in the case of a remote object). 1888 1889 if PK = N_Selected_Component 1890 and then Is_Tag (Entity (Selector_Name (Parent (N)))) 1891 then 1892 return; 1893 end if; 1894 1895 Error_Msg_N 1896 ("invalid dereference of a remote access-to-class-wide value", N); 1897 end if; 1898 end Validate_Remote_Access_To_Class_Wide_Type; 1899 1900 ------------------------------------------ 1901 -- Validate_Remote_Type_Type_Conversion -- 1902 ------------------------------------------ 1903 1904 procedure Validate_Remote_Type_Type_Conversion (N : Node_Id) is 1905 S : constant Entity_Id := Etype (N); 1906 E : constant Entity_Id := Etype (Expression (N)); 1907 1908 begin 1909 -- This test is required in the case where a conversion appears inside a 1910 -- normal package, it does not necessarily have to be inside an RCI, 1911 -- Remote_Types unit (RM E.2.2(9,12)). 1912 1913 if Is_Remote_Access_To_Subprogram_Type (E) 1914 and then not Is_Remote_Access_To_Subprogram_Type (S) 1915 then 1916 Error_Msg_N 1917 ("incorrect conversion of remote operand to local type", N); 1918 return; 1919 1920 elsif not Is_Remote_Access_To_Subprogram_Type (E) 1921 and then Is_Remote_Access_To_Subprogram_Type (S) 1922 then 1923 Error_Msg_N 1924 ("incorrect conversion of local operand to remote type", N); 1925 return; 1926 1927 elsif Is_Remote_Access_To_Class_Wide_Type (E) 1928 and then not Is_Remote_Access_To_Class_Wide_Type (S) 1929 then 1930 Error_Msg_N 1931 ("incorrect conversion of remote operand to local type", N); 1932 return; 1933 end if; 1934 1935 -- If a local access type is converted into a RACW type, then the 1936 -- current unit has a pointer that may now be exported to another 1937 -- partition. 1938 1939 if Is_Remote_Access_To_Class_Wide_Type (S) 1940 and then not Is_Remote_Access_To_Class_Wide_Type (E) 1941 then 1942 Set_Has_RACW (Current_Sem_Unit); 1943 end if; 1944 end Validate_Remote_Type_Type_Conversion; 1945 1946 ------------------------------- 1947 -- Validate_RT_RAT_Component -- 1948 ------------------------------- 1949 1950 procedure Validate_RT_RAT_Component (N : Node_Id) is 1951 Spec : constant Node_Id := Specification (N); 1952 Name_U : constant Entity_Id := Defining_Entity (Spec); 1953 Typ : Entity_Id; 1954 U_Typ : Entity_Id; 1955 First_Priv_Ent : constant Entity_Id := First_Private_Entity (Name_U); 1956 1957 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean; 1958 -- True if any stream attribute is available for Typ 1959 1960 --------------------------------- 1961 -- Stream_Attributes_Available -- 1962 --------------------------------- 1963 1964 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean 1965 is 1966 begin 1967 return Stream_Attribute_Available (Typ, TSS_Stream_Read) 1968 or else 1969 Stream_Attribute_Available (Typ, TSS_Stream_Write) 1970 or else 1971 Stream_Attribute_Available (Typ, TSS_Stream_Input) 1972 or else 1973 Stream_Attribute_Available (Typ, TSS_Stream_Output); 1974 end Stream_Attributes_Available; 1975 1976 -- Start of processing for Validate_RT_RAT_Component 1977 1978 begin 1979 if not Is_Remote_Types (Name_U) then 1980 return; 1981 end if; 1982 1983 Typ := First_Entity (Name_U); 1984 while Present (Typ) and then Typ /= First_Priv_Ent loop 1985 U_Typ := Underlying_Type (Base_Type (Typ)); 1986 1987 if No (U_Typ) then 1988 U_Typ := Typ; 1989 end if; 1990 1991 if Comes_From_Source (Typ) and then Is_Type (Typ) 1992 and then Ekind (Typ) /= E_Incomplete_Type 1993 then 1994 -- Check that the type can be meaningfully transmitted to another 1995 -- partition (E.2.2(8)). 1996 1997 if (Ada_Version < Ada_2005 and then Has_Non_Remote_Access (U_Typ)) 1998 or else (Stream_Attributes_Available (Typ) 1999 and then No_External_Streaming (U_Typ)) 2000 then 2001 if Is_Non_Remote_Access_Type (Typ) then 2002 Error_Msg_N ("error in non-remote access type", U_Typ); 2003 else 2004 Error_Msg_N 2005 ("error in record type containing a component of a " & 2006 "non-remote access type", U_Typ); 2007 end if; 2008 2009 if Ada_Version >= Ada_2005 then 2010 Error_Msg_N 2011 ("\must have visible Read and Write attribute " & 2012 "definition clauses (RM E.2.2(8))", U_Typ); 2013 else 2014 Error_Msg_N 2015 ("\must have Read and Write attribute " & 2016 "definition clauses (RM E.2.2(8))", U_Typ); 2017 end if; 2018 end if; 2019 end if; 2020 2021 Next_Entity (Typ); 2022 end loop; 2023 end Validate_RT_RAT_Component; 2024 2025 ----------------------------------------- 2026 -- Validate_SP_Access_Object_Type_Decl -- 2027 ----------------------------------------- 2028 2029 procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id) is 2030 Direct_Designated_Type : Entity_Id; 2031 2032 function Has_Entry_Declarations (E : Entity_Id) return Boolean; 2033 -- Return true if the protected type designated by T has entry 2034 -- declarations. 2035 2036 ---------------------------- 2037 -- Has_Entry_Declarations -- 2038 ---------------------------- 2039 2040 function Has_Entry_Declarations (E : Entity_Id) return Boolean is 2041 Ety : Entity_Id; 2042 2043 begin 2044 if Nkind (Parent (E)) = N_Protected_Type_Declaration then 2045 Ety := First_Entity (E); 2046 while Present (Ety) loop 2047 if Ekind (Ety) = E_Entry then 2048 return True; 2049 end if; 2050 2051 Next_Entity (Ety); 2052 end loop; 2053 end if; 2054 2055 return False; 2056 end Has_Entry_Declarations; 2057 2058 -- Start of processing for Validate_SP_Access_Object_Type_Decl 2059 2060 begin 2061 -- We are called from Sem_Ch3.Analyze_Full_Type_Declaration, and the 2062 -- Nkind of the given entity is N_Access_To_Object_Definition. 2063 2064 if not Comes_From_Source (T) 2065 or else not In_Shared_Passive_Unit 2066 or else In_Subprogram_Task_Protected_Unit 2067 then 2068 return; 2069 end if; 2070 2071 -- Check Shared Passive unit. It should not contain the declaration 2072 -- of an access-to-object type whose designated type is a class-wide 2073 -- type, task type or protected type with entry (RM E.2.1(7)). 2074 2075 Direct_Designated_Type := Designated_Type (T); 2076 2077 if Ekind (Direct_Designated_Type) = E_Class_Wide_Type then 2078 Error_Msg_N 2079 ("invalid access-to-class-wide type in shared passive unit", T); 2080 return; 2081 2082 elsif Ekind (Direct_Designated_Type) in Task_Kind then 2083 Error_Msg_N 2084 ("invalid access-to-task type in shared passive unit", T); 2085 return; 2086 2087 elsif Ekind (Direct_Designated_Type) in Protected_Kind 2088 and then Has_Entry_Declarations (Direct_Designated_Type) 2089 then 2090 Error_Msg_N 2091 ("invalid access-to-protected type in shared passive unit", T); 2092 return; 2093 end if; 2094 end Validate_SP_Access_Object_Type_Decl; 2095 2096 --------------------------------- 2097 -- Validate_Static_Object_Name -- 2098 --------------------------------- 2099 2100 procedure Validate_Static_Object_Name (N : Node_Id) is 2101 E : Entity_Id; 2102 Val : Node_Id; 2103 2104 function Is_Primary (N : Node_Id) return Boolean; 2105 -- Determine whether node is syntactically a primary in an expression 2106 -- This function should probably be somewhere else ??? 2107 -- 2108 -- Also it does not do what it says, e.g if N is a binary operator 2109 -- whose parent is a binary operator, Is_Primary returns True ??? 2110 2111 ---------------- 2112 -- Is_Primary -- 2113 ---------------- 2114 2115 function Is_Primary (N : Node_Id) return Boolean is 2116 K : constant Node_Kind := Nkind (Parent (N)); 2117 2118 begin 2119 case K is 2120 when N_Aggregate 2121 | N_Component_Association 2122 | N_Index_Or_Discriminant_Constraint 2123 | N_Membership_Test 2124 | N_Op 2125 | N_Range 2126 => 2127 return True; 2128 2129 when N_Attribute_Reference => 2130 declare 2131 Attr : constant Name_Id := Attribute_Name (Parent (N)); 2132 2133 begin 2134 return Attr /= Name_Address 2135 and then Attr /= Name_Access 2136 and then Attr /= Name_Unchecked_Access 2137 and then Attr /= Name_Unrestricted_Access; 2138 end; 2139 2140 when N_Indexed_Component => 2141 return N /= Prefix (Parent (N)) or else Is_Primary (Parent (N)); 2142 2143 when N_Qualified_Expression 2144 | N_Type_Conversion 2145 => 2146 return Is_Primary (Parent (N)); 2147 2148 when N_Assignment_Statement 2149 | N_Object_Declaration 2150 => 2151 return N = Expression (Parent (N)); 2152 2153 when N_Selected_Component => 2154 return Is_Primary (Parent (N)); 2155 2156 when others => 2157 return False; 2158 end case; 2159 end Is_Primary; 2160 2161 -- Start of processing for Validate_Static_Object_Name 2162 2163 begin 2164 if not In_Preelaborated_Unit 2165 or else not Comes_From_Source (N) 2166 or else In_Subprogram_Or_Concurrent_Unit 2167 or else Ekind (Current_Scope) = E_Block 2168 then 2169 return; 2170 2171 -- Filter out cases where primary is default in a component declaration, 2172 -- discriminant specification, or actual in a record type initialization 2173 -- call. 2174 2175 -- Initialization call of internal types 2176 2177 elsif Nkind (Parent (N)) = N_Procedure_Call_Statement then 2178 2179 if Present (Parent (Parent (N))) 2180 and then Nkind (Parent (Parent (N))) = N_Freeze_Entity 2181 then 2182 return; 2183 end if; 2184 2185 if Nkind (Name (Parent (N))) = N_Identifier 2186 and then not Comes_From_Source (Entity (Name (Parent (N)))) 2187 then 2188 return; 2189 end if; 2190 end if; 2191 2192 -- Error if the name is a primary in an expression. The parent must not 2193 -- be an operator, or a selected component or an indexed component that 2194 -- is itself a primary. Entities that are actuals do not need to be 2195 -- checked, because the call itself will be diagnosed. Entities in a 2196 -- generic unit or within a preanalyzed expression are not checked: 2197 -- only their use in executable code matters. 2198 2199 if Is_Primary (N) 2200 and then (not Inside_A_Generic 2201 or else Present (Enclosing_Generic_Body (N))) 2202 and then not In_Spec_Expression 2203 then 2204 if Ekind (Entity (N)) = E_Variable 2205 or else Ekind (Entity (N)) in Formal_Object_Kind 2206 then 2207 Flag_Non_Static_Expr 2208 ("non-static object name in preelaborated unit", N); 2209 2210 -- Give an error for a reference to a nonstatic constant, unless the 2211 -- constant is in another GNAT library unit that is preelaborable. 2212 2213 elsif Ekind (Entity (N)) = E_Constant 2214 and then not Is_Static_Expression (N) 2215 then 2216 E := Entity (N); 2217 Val := Constant_Value (E); 2218 2219 if In_Internal_Unit (N) 2220 and then 2221 Enclosing_Comp_Unit_Node (N) /= Enclosing_Comp_Unit_Node (E) 2222 and then (Is_Preelaborated (Scope (E)) 2223 or else Is_Pure (Scope (E)) 2224 or else (Present (Renamed_Object (E)) 2225 and then Is_Entity_Name (Renamed_Object (E)) 2226 and then 2227 (Is_Preelaborated 2228 (Scope (Renamed_Object (E))) 2229 or else 2230 Is_Pure 2231 (Scope (Renamed_Object (E)))))) 2232 then 2233 null; 2234 2235 -- If the value of the constant is a local variable that renames 2236 -- an aggregate, this is in itself legal. The aggregate may be 2237 -- expanded into a loop, but this does not affect preelaborability 2238 -- in itself. If some aggregate components are non-static, that is 2239 -- to say if they involve non static primaries, they will be 2240 -- flagged when analyzed. 2241 2242 elsif Present (Val) 2243 and then Is_Entity_Name (Val) 2244 and then Is_Array_Type (Etype (Val)) 2245 and then not Comes_From_Source (Val) 2246 and then Nkind (Original_Node (Val)) = N_Aggregate 2247 then 2248 null; 2249 2250 -- This is the error case 2251 2252 else 2253 -- In GNAT mode or Relaxed RM Semantic mode, this is just a 2254 -- warning, to allow it to be judiciously turned off. 2255 -- Otherwise it is a real error. 2256 2257 if GNAT_Mode or Relaxed_RM_Semantics then 2258 Error_Msg_N 2259 ("??non-static constant in preelaborated unit", N); 2260 else 2261 Flag_Non_Static_Expr 2262 ("non-static constant in preelaborated unit", N); 2263 end if; 2264 end if; 2265 end if; 2266 end if; 2267 end Validate_Static_Object_Name; 2268 2269end Sem_Cat; 2270