1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S E M _ C A T -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1992-2019, 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. 725 726 if Nkind (P) /= N_Compilation_Unit then 727 return; 728 end if; 729 730 declare 731 PN : Node_Id; 732 733 begin 734 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then 735 Set_Parents (True); 736 end if; 737 738 PN := First (Pragmas_After (Aux_Decls_Node (P))); 739 while Present (PN) loop 740 741 -- Skip implicit types that may have been introduced by 742 -- previous analysis. 743 744 if Nkind (PN) = N_Pragma then 745 case Get_Pragma_Id (PN) is 746 when Pragma_All_Calls_Remote 747 | Pragma_Preelaborate 748 | Pragma_Pure 749 | Pragma_Remote_Call_Interface 750 | Pragma_Remote_Types 751 | Pragma_Shared_Passive 752 => 753 Analyze (PN); 754 755 when others => 756 null; 757 end case; 758 end if; 759 760 Next (PN); 761 end loop; 762 763 if Is_Child_Unit (S) and then Is_Generic_Instance (S) then 764 Set_Parents (False); 765 end if; 766 end; 767 end Set_Categorization_From_Pragmas; 768 769 ----------------------------------- 770 -- Set_Categorization_From_Scope -- 771 ----------------------------------- 772 773 procedure Set_Categorization_From_Scope (E : Entity_Id; Scop : Entity_Id) is 774 Declaration : Node_Id := Empty; 775 Specification : Node_Id := Empty; 776 777 begin 778 -- Do not modify the purity of an internally generated entity if it has 779 -- been explicitly marked as pure for optimization purposes. 780 781 if not Has_Pragma_Pure_Function (E) then 782 Set_Is_Pure 783 (E, Is_Pure (Scop) and then Is_Library_Level_Entity (E)); 784 end if; 785 786 if not Is_Remote_Call_Interface (E) then 787 if Ekind (E) in Subprogram_Kind then 788 Declaration := Unit_Declaration_Node (E); 789 790 if Nkind_In (Declaration, N_Subprogram_Body, 791 N_Subprogram_Renaming_Declaration) 792 then 793 Specification := Corresponding_Spec (Declaration); 794 end if; 795 end if; 796 797 -- A subprogram body or renaming-as-body is a remote call interface 798 -- if it serves as the completion of a subprogram declaration that 799 -- is a remote call interface. 800 801 if Nkind (Specification) in N_Entity then 802 Set_Is_Remote_Call_Interface 803 (E, Is_Remote_Call_Interface (Specification)); 804 805 -- A subprogram declaration is a remote call interface when it is 806 -- declared within the visible part of, or declared by, a library 807 -- unit declaration that is a remote call interface. 808 809 else 810 Set_Is_Remote_Call_Interface 811 (E, Is_Remote_Call_Interface (Scop) 812 and then not (In_Private_Part (Scop) 813 or else In_Package_Body (Scop))); 814 end if; 815 end if; 816 817 Set_Is_Remote_Types 818 (E, Is_Remote_Types (Scop) 819 and then not (In_Private_Part (Scop) 820 or else In_Package_Body (Scop))); 821 end Set_Categorization_From_Scope; 822 823 ------------------------------ 824 -- Static_Discriminant_Expr -- 825 ------------------------------ 826 827 -- We need to accommodate a Why_Not_Static call somehow here ??? 828 829 function Static_Discriminant_Expr (L : List_Id) return Boolean is 830 Discriminant_Spec : Node_Id; 831 832 begin 833 Discriminant_Spec := First (L); 834 while Present (Discriminant_Spec) loop 835 if Present (Expression (Discriminant_Spec)) 836 and then 837 not Is_OK_Static_Expression (Expression (Discriminant_Spec)) 838 then 839 return False; 840 end if; 841 842 Next (Discriminant_Spec); 843 end loop; 844 845 return True; 846 end Static_Discriminant_Expr; 847 848 -------------------------------------- 849 -- Validate_Access_Type_Declaration -- 850 -------------------------------------- 851 852 procedure Validate_Access_Type_Declaration (T : Entity_Id; N : Node_Id) is 853 Def : constant Node_Id := Type_Definition (N); 854 855 begin 856 case Nkind (Def) is 857 858 -- Access to subprogram case 859 860 when N_Access_To_Subprogram_Definition => 861 862 -- A pure library_item must not contain the declaration of a 863 -- named access type, except within a subprogram, generic 864 -- subprogram, task unit, or protected unit (RM 10.2.1(16)). 865 866 -- This test is skipped in Ada 2005 (see AI-366) 867 868 if Ada_Version < Ada_2005 869 and then Comes_From_Source (T) 870 and then In_Pure_Unit 871 and then not In_Subprogram_Task_Protected_Unit 872 then 873 Error_Msg_N ("named access type not allowed in pure unit", T); 874 end if; 875 876 -- Access to object case 877 878 when N_Access_To_Object_Definition => 879 if Comes_From_Source (T) 880 and then In_Pure_Unit 881 and then not In_Subprogram_Task_Protected_Unit 882 then 883 -- We can't give the message yet, since the type is not frozen 884 -- and in Ada 2005 mode, access types are allowed in pure units 885 -- if the type has no storage pool (see AI-366). So we set a 886 -- flag which will be checked at freeze time. 887 888 Set_Is_Pure_Unit_Access_Type (T); 889 end if; 890 891 -- Check for RCI or RT unit type declaration: declaration of an 892 -- access-to-object type is illegal unless it is a general access 893 -- type that designates a class-wide limited private type. 894 -- Note that constraints on the primitive subprograms of the 895 -- designated tagged type are not enforced here but in 896 -- Validate_RACW_Primitives, which is done separately because the 897 -- designated type might not be frozen (and therefore its 898 -- primitive operations might not be completely known) at the 899 -- point of the RACW declaration. 900 901 Validate_Remote_Access_Object_Type_Declaration (T); 902 903 -- Check for shared passive unit type declaration. It should 904 -- not contain the declaration of access to class wide type, 905 -- access to task type and access to protected type with entry. 906 907 Validate_SP_Access_Object_Type_Decl (T); 908 909 when others => 910 null; 911 end case; 912 913 -- Set categorization flag from package on entity as well, to allow 914 -- easy checks later on for required validations of RCI or RT units. 915 -- This is only done for entities that are in the original source. 916 917 if Comes_From_Source (T) 918 and then not (In_Package_Body (Scope (T)) 919 or else In_Private_Part (Scope (T))) 920 then 921 Set_Is_Remote_Call_Interface 922 (T, Is_Remote_Call_Interface (Scope (T))); 923 Set_Is_Remote_Types 924 (T, Is_Remote_Types (Scope (T))); 925 end if; 926 end Validate_Access_Type_Declaration; 927 928 ---------------------------- 929 -- Validate_Ancestor_Part -- 930 ---------------------------- 931 932 procedure Validate_Ancestor_Part (N : Node_Id) is 933 A : constant Node_Id := Ancestor_Part (N); 934 T : constant Entity_Id := Entity (A); 935 936 begin 937 if In_Preelaborated_Unit 938 and then not In_Subprogram_Or_Concurrent_Unit 939 and then (not Inside_A_Generic 940 or else Present (Enclosing_Generic_Body (N))) 941 then 942 -- If the type is private, it must have the Ada 2005 pragma 943 -- Has_Preelaborable_Initialization. 944 945 -- The check is omitted within predefined units. This is probably 946 -- obsolete code to fix the Ada 95 weakness in this area ??? 947 948 if Is_Private_Type (T) 949 and then not Has_Pragma_Preelab_Init (T) 950 and then not In_Internal_Unit (N) 951 then 952 Error_Msg_N 953 ("private ancestor type not allowed in preelaborated unit", A); 954 955 elsif Is_Record_Type (T) then 956 if Nkind (Parent (T)) = N_Full_Type_Declaration then 957 Check_Non_Static_Default_Expr 958 (Type_Definition (Parent (T)), A); 959 end if; 960 end if; 961 end if; 962 end Validate_Ancestor_Part; 963 964 ---------------------------------------- 965 -- Validate_Categorization_Dependency -- 966 ---------------------------------------- 967 968 procedure Validate_Categorization_Dependency 969 (N : Node_Id; 970 E : Entity_Id) 971 is 972 K : constant Node_Kind := Nkind (N); 973 P : Node_Id := Parent (N); 974 U : Entity_Id := E; 975 Is_Subunit : constant Boolean := Nkind (P) = N_Subunit; 976 977 begin 978 -- Only validate library units and subunits. For subunits, checks 979 -- concerning withed units apply to the parent compilation unit. 980 981 if Is_Subunit then 982 P := Parent (P); 983 U := Scope (E); 984 985 while Present (U) 986 and then not Is_Compilation_Unit (U) 987 and then not Is_Child_Unit (U) 988 loop 989 U := Scope (U); 990 end loop; 991 end if; 992 993 if Nkind (P) /= N_Compilation_Unit then 994 return; 995 end if; 996 997 -- Body of RCI unit does not need validation 998 999 if Is_Remote_Call_Interface (E) 1000 and then Nkind_In (N, N_Package_Body, N_Subprogram_Body) 1001 then 1002 return; 1003 end if; 1004 1005 -- Ada 2005 (AI-50217): Process explicit non-limited with_clauses 1006 1007 declare 1008 Item : Node_Id; 1009 Entity_Of_Withed : Entity_Id; 1010 1011 begin 1012 Item := First (Context_Items (P)); 1013 while Present (Item) loop 1014 if Nkind (Item) = N_With_Clause 1015 and then 1016 not (Implicit_With (Item) 1017 or else Limited_Present (Item) 1018 1019 -- Skip if error already posted on the WITH clause (in 1020 -- which case the Name attribute may be invalid). In 1021 -- particular, this fixes the problem of hanging in the 1022 -- presence of a WITH clause on a child that is an 1023 -- illegal generic instantiation. 1024 1025 or else Error_Posted (Item)) 1026 and then 1027 not (Try_Semantics 1028 1029 -- Skip processing malformed trees 1030 1031 and then Nkind (Name (Item)) not in N_Has_Entity) 1032 then 1033 Entity_Of_Withed := Entity (Name (Item)); 1034 Check_Categorization_Dependencies 1035 (U, Entity_Of_Withed, Item, Is_Subunit); 1036 end if; 1037 1038 Next (Item); 1039 end loop; 1040 end; 1041 1042 -- Child depends on parent; therefore parent should also be categorized 1043 -- and satisfy the dependency hierarchy. 1044 1045 -- Check if N is a child spec 1046 1047 if (K in N_Generic_Declaration or else 1048 K in N_Generic_Instantiation or else 1049 K in N_Generic_Renaming_Declaration or else 1050 K = N_Package_Declaration or else 1051 K = N_Package_Renaming_Declaration or else 1052 K = N_Subprogram_Declaration or else 1053 K = N_Subprogram_Renaming_Declaration) 1054 and then Present (Parent_Spec (N)) 1055 then 1056 Check_Categorization_Dependencies (E, Scope (E), N, False); 1057 1058 -- Verify that public child of an RCI library unit must also be an 1059 -- RCI library unit (RM E.2.3(15)). 1060 1061 if Is_Remote_Call_Interface (Scope (E)) 1062 and then not Private_Present (P) 1063 and then not Is_Remote_Call_Interface (E) 1064 then 1065 Error_Msg_N ("public child of rci unit must also be rci unit", N); 1066 end if; 1067 end if; 1068 end Validate_Categorization_Dependency; 1069 1070 -------------------------------- 1071 -- Validate_Controlled_Object -- 1072 -------------------------------- 1073 1074 procedure Validate_Controlled_Object (E : Entity_Id) is 1075 begin 1076 -- Don't need this check in Ada 2005 mode, where this is all taken 1077 -- care of by the mechanism for Preelaborable Initialization. 1078 1079 if Ada_Version >= Ada_2005 then 1080 return; 1081 end if; 1082 1083 -- For now, never apply this check for internal GNAT units, since we 1084 -- have a number of cases in the library where we are stuck with objects 1085 -- of this type, and the RM requires Preelaborate. 1086 1087 -- For similar reasons, we only do this check for source entities, since 1088 -- we generate entities of this type in some situations. 1089 1090 -- Note that the 10.2.1(9) restrictions are not relevant to us anyway. 1091 -- We have to enforce them for RM compatibility, but we have no trouble 1092 -- accepting these objects and doing the right thing. Note that there is 1093 -- no requirement that Preelaborate not actually generate any code. 1094 1095 if In_Preelaborated_Unit 1096 and then not Debug_Flag_PP 1097 and then Comes_From_Source (E) 1098 and then not In_Internal_Unit (E) 1099 and then (not Inside_A_Generic 1100 or else Present (Enclosing_Generic_Body (E))) 1101 and then not Is_Protected_Type (Etype (E)) 1102 then 1103 Error_Msg_N 1104 ("library level controlled object not allowed in " & 1105 "preelaborated unit", E); 1106 end if; 1107 end Validate_Controlled_Object; 1108 1109 -------------------------------------- 1110 -- Validate_Null_Statement_Sequence -- 1111 -------------------------------------- 1112 1113 procedure Validate_Null_Statement_Sequence (N : Node_Id) is 1114 Item : Node_Id; 1115 1116 begin 1117 if In_Preelaborated_Unit then 1118 Item := First (Statements (Handled_Statement_Sequence (N))); 1119 while Present (Item) loop 1120 if Nkind (Item) /= N_Label 1121 and then Nkind (Item) /= N_Null_Statement 1122 then 1123 -- In GNAT mode, this is a warning, allowing the run-time 1124 -- to judiciously bypass this error condition. 1125 1126 Error_Msg_Warn := GNAT_Mode; 1127 Error_Msg_N 1128 ("<<statements not allowed in preelaborated unit", Item); 1129 1130 exit; 1131 end if; 1132 1133 Next (Item); 1134 end loop; 1135 end if; 1136 end Validate_Null_Statement_Sequence; 1137 1138 --------------------------------- 1139 -- Validate_Object_Declaration -- 1140 --------------------------------- 1141 1142 procedure Validate_Object_Declaration (N : Node_Id) is 1143 Id : constant Entity_Id := Defining_Identifier (N); 1144 E : constant Node_Id := Expression (N); 1145 Odf : constant Node_Id := Object_Definition (N); 1146 T : constant Entity_Id := Etype (Id); 1147 1148 begin 1149 -- Verify that any access to subprogram object does not have in its 1150 -- subprogram profile access type parameters or limited parameters 1151 -- without Read and Write attributes (E.2.3(13)). 1152 1153 Validate_RCI_Subprogram_Declaration (N); 1154 1155 -- Check that if we are in preelaborated elaboration code, then we 1156 -- do not have an instance of a default initialized private, task or 1157 -- protected object declaration which would violate (RM 10.2.1(9)). 1158 -- Note that constants are never default initialized (and the test 1159 -- below also filters out deferred constants). A variable is default 1160 -- initialized if it does *not* have an initialization expression. 1161 1162 -- Filter out cases that are not declaration of a variable from source 1163 1164 if Nkind (N) /= N_Object_Declaration 1165 or else Constant_Present (N) 1166 or else not Comes_From_Source (Id) 1167 then 1168 return; 1169 end if; 1170 1171 -- Exclude generic specs from the checks (this will get rechecked 1172 -- on instantiations). 1173 1174 if Inside_A_Generic and then No (Enclosing_Generic_Body (Id)) then 1175 return; 1176 end if; 1177 1178 -- Required checks for declaration that is in a preelaborated package 1179 -- and is not within some subprogram. 1180 1181 if In_Preelaborated_Unit 1182 and then not In_Subprogram_Or_Concurrent_Unit 1183 then 1184 -- Check for default initialized variable case. Note that in 1185 -- accordance with (RM B.1(24)) imported objects are not subject to 1186 -- default initialization. 1187 -- If the initialization does not come from source and is an 1188 -- aggregate, it is a static initialization that replaces an 1189 -- implicit call, and must be treated as such. 1190 1191 if Present (E) 1192 and then (Comes_From_Source (E) or else Nkind (E) /= N_Aggregate) 1193 then 1194 null; 1195 1196 elsif Is_Imported (Id) then 1197 null; 1198 1199 else 1200 declare 1201 Ent : Entity_Id := T; 1202 1203 begin 1204 -- An array whose component type is a record with nonstatic 1205 -- default expressions is a violation, so we get the array's 1206 -- component type. 1207 1208 if Is_Array_Type (Ent) then 1209 declare 1210 Comp_Type : Entity_Id; 1211 1212 begin 1213 Comp_Type := Component_Type (Ent); 1214 while Is_Array_Type (Comp_Type) loop 1215 Comp_Type := Component_Type (Comp_Type); 1216 end loop; 1217 1218 Ent := Comp_Type; 1219 end; 1220 end if; 1221 1222 -- Object decl. that is of record type and has no default expr. 1223 -- should check if there is any non-static default expression 1224 -- in component decl. of the record type decl. 1225 1226 if Is_Record_Type (Ent) then 1227 if Nkind (Parent (Ent)) = N_Full_Type_Declaration then 1228 Check_Non_Static_Default_Expr 1229 (Type_Definition (Parent (Ent)), N); 1230 1231 elsif Nkind (Odf) = N_Subtype_Indication 1232 and then not Is_Array_Type (T) 1233 and then not Is_Private_Type (T) 1234 then 1235 Check_Non_Static_Default_Expr (Type_Definition 1236 (Parent (Entity (Subtype_Mark (Odf)))), N); 1237 end if; 1238 end if; 1239 1240 -- Check for invalid use of private object. Note that Ada 2005 1241 -- AI-161 modifies the rules for Ada 2005, including the use of 1242 -- the new pragma Preelaborable_Initialization. 1243 1244 if Is_Private_Type (Ent) 1245 or else Depends_On_Private (Ent) 1246 then 1247 -- Case where type has preelaborable initialization which 1248 -- means that a pragma Preelaborable_Initialization was 1249 -- given for the private type. 1250 1251 if Relaxed_RM_Semantics then 1252 1253 -- In relaxed mode, do not issue these messages, this 1254 -- is basically similar to the GNAT_Mode test below. 1255 1256 null; 1257 1258 elsif Has_Preelaborable_Initialization (Ent) then 1259 1260 -- But for the predefined units, we will ignore this 1261 -- status unless we are in Ada 2005 mode since we want 1262 -- Ada 95 compatible behavior, in which the entities 1263 -- marked with this pragma in the predefined library are 1264 -- not treated specially. 1265 1266 if Ada_Version < Ada_2005 then 1267 Error_Msg_N 1268 ("private object not allowed in preelaborated unit", 1269 N); 1270 Error_Msg_N ("\(would be legal in Ada 2005 mode)", N); 1271 end if; 1272 1273 -- Type does not have preelaborable initialization 1274 1275 else 1276 -- We allow this when compiling in GNAT mode to make life 1277 -- easier for some cases where it would otherwise be hard 1278 -- to be exactly valid Ada. 1279 1280 if not GNAT_Mode then 1281 Error_Msg_N 1282 ("private object not allowed in preelaborated unit", 1283 N); 1284 1285 -- Add a message if it would help to provide a pragma 1286 -- Preelaborable_Initialization on the type of the 1287 -- object (which would make it legal in Ada 2005). 1288 1289 -- If the type has no full view (generic type, or 1290 -- previous error), the warning does not apply. 1291 1292 if Is_Private_Type (Ent) 1293 and then Present (Full_View (Ent)) 1294 and then 1295 Has_Preelaborable_Initialization (Full_View (Ent)) 1296 then 1297 Error_Msg_Sloc := Sloc (Ent); 1298 1299 if Ada_Version >= Ada_2005 then 1300 Error_Msg_NE 1301 ("\would be legal if pragma Preelaborable_" & 1302 "Initialization given for & #", N, Ent); 1303 else 1304 Error_Msg_NE 1305 ("\would be legal in Ada 2005 if pragma " & 1306 "Preelaborable_Initialization given for & #", 1307 N, Ent); 1308 end if; 1309 end if; 1310 end if; 1311 end if; 1312 1313 -- Access to Task or Protected type 1314 1315 elsif Is_Entity_Name (Odf) 1316 and then Present (Etype (Odf)) 1317 and then Is_Access_Type (Etype (Odf)) 1318 then 1319 Ent := Designated_Type (Etype (Odf)); 1320 1321 elsif Is_Entity_Name (Odf) then 1322 Ent := Entity (Odf); 1323 1324 elsif Nkind (Odf) = N_Subtype_Indication then 1325 Ent := Etype (Subtype_Mark (Odf)); 1326 1327 elsif Nkind (Odf) = N_Constrained_Array_Definition then 1328 Ent := Component_Type (T); 1329 end if; 1330 1331 if Is_Task_Type (Ent) 1332 or else (Is_Protected_Type (Ent) and then Has_Entries (Ent)) 1333 then 1334 Error_Msg_N 1335 ("concurrent object not allowed in preelaborated unit", 1336 N); 1337 return; 1338 end if; 1339 end; 1340 end if; 1341 1342 -- Non-static discriminants not allowed in preelaborated unit. 1343 -- Objects of a controlled type with a user-defined Initialize 1344 -- are forbidden as well. 1345 1346 if Is_Record_Type (Etype (Id)) then 1347 declare 1348 ET : constant Entity_Id := Etype (Id); 1349 EE : constant Entity_Id := Etype (Etype (Id)); 1350 PEE : Node_Id; 1351 1352 begin 1353 if Has_Discriminants (ET) and then Present (EE) then 1354 PEE := Parent (EE); 1355 1356 if Nkind (PEE) = N_Full_Type_Declaration 1357 and then not Static_Discriminant_Expr 1358 (Discriminant_Specifications (PEE)) 1359 then 1360 Error_Msg_N 1361 ("non-static discriminant in preelaborated unit", 1362 PEE); 1363 end if; 1364 end if; 1365 1366 -- For controlled type or type with controlled component, check 1367 -- preelaboration flag, as there may be a non-null Initialize 1368 -- primitive. For language versions earlier than Ada 2005, 1369 -- there is no notion of preelaborable initialization, and 1370 -- Validate_Controlled_Object is used to enforce rules for 1371 -- controlled objects. 1372 1373 if (Is_Controlled (ET) or else Has_Controlled_Component (ET)) 1374 and then Ada_Version >= Ada_2005 1375 and then not Has_Preelaborable_Initialization (ET) 1376 then 1377 Error_Msg_NE 1378 ("controlled type& does not have" 1379 & " preelaborable initialization", N, ET); 1380 end if; 1381 end; 1382 1383 end if; 1384 end if; 1385 1386 -- A pure library_item must not contain the declaration of any variable 1387 -- except within a subprogram, generic subprogram, task unit, or 1388 -- protected unit (RM 10.2.1(16)). 1389 1390 if In_Pure_Unit and then not In_Subprogram_Task_Protected_Unit then 1391 Error_Msg_N ("declaration of variable not allowed in pure unit", N); 1392 1393 elsif not In_Private_Part (Id) then 1394 1395 -- The visible part of an RCI library unit must not contain the 1396 -- declaration of a variable (RM E.1.3(9)). 1397 1398 if In_RCI_Declaration then 1399 Error_Msg_N ("visible variable not allowed in 'R'C'I unit", N); 1400 1401 -- The visible part of a Shared Passive library unit must not contain 1402 -- the declaration of a variable (RM E.2.2(7)). 1403 1404 elsif In_RT_Declaration then 1405 Error_Msg_N 1406 ("visible variable not allowed in remote types unit", N); 1407 end if; 1408 end if; 1409 end Validate_Object_Declaration; 1410 1411 ----------------------------- 1412 -- Validate_RACW_Primitive -- 1413 ----------------------------- 1414 1415 procedure Validate_RACW_Primitive 1416 (Subp : Entity_Id; 1417 RACW : Entity_Id) 1418 is 1419 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id); 1420 -- Diagnose illegality on N. If RACW is present, report the error on it 1421 -- rather than on N. 1422 1423 ------------------------- 1424 -- Illegal_Remote_Subp -- 1425 ------------------------- 1426 1427 procedure Illegal_Remote_Subp (Msg : String; N : Node_Id) is 1428 begin 1429 if Present (RACW) then 1430 if not Error_Posted (RACW) then 1431 Error_Msg_N 1432 ("illegal remote access to class-wide type&", RACW); 1433 end if; 1434 1435 Error_Msg_Sloc := Sloc (N); 1436 Error_Msg_NE ("\\" & Msg & " in primitive& #", RACW, Subp); 1437 1438 else 1439 Error_Msg_NE (Msg & " in remote subprogram&", N, Subp); 1440 end if; 1441 end Illegal_Remote_Subp; 1442 1443 Rtyp : Entity_Id; 1444 Param : Node_Id; 1445 Param_Spec : Node_Id; 1446 Param_Type : Entity_Id; 1447 1448 -- Start of processing for Validate_RACW_Primitive 1449 1450 begin 1451 -- Check return type 1452 1453 if Ekind (Subp) = E_Function then 1454 Rtyp := Etype (Subp); 1455 1456 -- AI05-0101 (Binding Interpretation): The result type of a remote 1457 -- function must either support external streaming or be a 1458 -- controlling access result type. 1459 1460 if Has_Controlling_Result (Subp) then 1461 null; 1462 1463 elsif Ekind (Rtyp) = E_Anonymous_Access_Type then 1464 Illegal_Remote_Subp ("anonymous access result", Rtyp); 1465 1466 elsif Is_Limited_Type (Rtyp) then 1467 if No (TSS (Rtyp, TSS_Stream_Read)) 1468 or else 1469 No (TSS (Rtyp, TSS_Stream_Write)) 1470 then 1471 Illegal_Remote_Subp 1472 ("limited return type must have Read and Write attributes", 1473 Parent (Subp)); 1474 Explain_Limited_Type (Rtyp, Parent (Subp)); 1475 end if; 1476 1477 -- Check that the return type supports external streaming 1478 1479 elsif No_External_Streaming (Rtyp) 1480 and then not Error_Posted (Rtyp) 1481 then 1482 Illegal_Remote_Subp ("return type containing non-remote access " 1483 & "must have Read and Write attributes", 1484 Parent (Subp)); 1485 end if; 1486 end if; 1487 1488 Param := First_Formal (Subp); 1489 while Present (Param) loop 1490 1491 -- Now find out if this parameter is a controlling parameter 1492 1493 Param_Spec := Parent (Param); 1494 Param_Type := Etype (Param); 1495 1496 if Is_Controlling_Formal (Param) then 1497 1498 -- It is a controlling parameter, so specific checks below do not 1499 -- apply. 1500 1501 null; 1502 1503 elsif Ekind_In (Param_Type, E_Anonymous_Access_Type, 1504 E_Anonymous_Access_Subprogram_Type) 1505 then 1506 -- From RM E.2.2(14), no anonymous access parameter other than 1507 -- controlling ones may be used (because an anonymous access 1508 -- type never supports external streaming). 1509 1510 Illegal_Remote_Subp 1511 ("non-controlling access parameter", Param_Spec); 1512 1513 elsif No_External_Streaming (Param_Type) 1514 and then not Error_Posted (Param_Type) 1515 then 1516 Illegal_Remote_Subp ("formal parameter in remote subprogram must " 1517 & "support external streaming", Param_Spec); 1518 end if; 1519 1520 -- Check next parameter in this subprogram 1521 1522 Next_Formal (Param); 1523 end loop; 1524 end Validate_RACW_Primitive; 1525 1526 ------------------------------ 1527 -- Validate_RACW_Primitives -- 1528 ------------------------------ 1529 1530 procedure Validate_RACW_Primitives (T : Entity_Id) is 1531 Desig_Type : Entity_Id; 1532 Primitive_Subprograms : Elist_Id; 1533 Subprogram_Elmt : Elmt_Id; 1534 Subprogram : Entity_Id; 1535 1536 begin 1537 Desig_Type := Etype (Designated_Type (T)); 1538 1539 -- No action needed for concurrent types 1540 1541 if Is_Concurrent_Type (Desig_Type) then 1542 return; 1543 end if; 1544 1545 Primitive_Subprograms := Primitive_Operations (Desig_Type); 1546 1547 Subprogram_Elmt := First_Elmt (Primitive_Subprograms); 1548 while Subprogram_Elmt /= No_Elmt loop 1549 Subprogram := Node (Subprogram_Elmt); 1550 1551 if Is_Predefined_Dispatching_Operation (Subprogram) 1552 or else Is_Hidden (Subprogram) 1553 then 1554 goto Next_Subprogram; 1555 end if; 1556 1557 Validate_RACW_Primitive (Subp => Subprogram, RACW => T); 1558 1559 <<Next_Subprogram>> 1560 Next_Elmt (Subprogram_Elmt); 1561 end loop; 1562 end Validate_RACW_Primitives; 1563 1564 ------------------------------- 1565 -- Validate_RCI_Declarations -- 1566 ------------------------------- 1567 1568 procedure Validate_RCI_Declarations (P : Entity_Id) is 1569 E : Entity_Id; 1570 1571 begin 1572 E := First_Entity (P); 1573 while Present (E) loop 1574 if Comes_From_Source (E) then 1575 if Is_Limited_Type (E) then 1576 Error_Msg_N 1577 ("limited type not allowed in rci unit", Parent (E)); 1578 Explain_Limited_Type (E, Parent (E)); 1579 1580 elsif Ekind_In (E, E_Generic_Function, 1581 E_Generic_Package, 1582 E_Generic_Procedure) 1583 then 1584 Error_Msg_N ("generic declaration not allowed in rci unit", 1585 Parent (E)); 1586 1587 elsif (Ekind (E) = E_Function or else Ekind (E) = E_Procedure) 1588 and then Has_Pragma_Inline (E) 1589 then 1590 Error_Msg_N 1591 ("inlined subprogram not allowed in rci unit", Parent (E)); 1592 1593 -- Inner packages that are renamings need not be checked. Generic 1594 -- RCI packages are subject to the checks, but entities that come 1595 -- from formal packages are not part of the visible declarations 1596 -- of the package and are not checked. 1597 1598 elsif Ekind (E) = E_Package then 1599 if Present (Renamed_Entity (E)) then 1600 null; 1601 1602 elsif Ekind (P) /= E_Generic_Package 1603 or else List_Containing (Unit_Declaration_Node (E)) /= 1604 Generic_Formal_Declarations 1605 (Unit_Declaration_Node (P)) 1606 then 1607 Validate_RCI_Declarations (E); 1608 end if; 1609 end if; 1610 end if; 1611 1612 Next_Entity (E); 1613 end loop; 1614 end Validate_RCI_Declarations; 1615 1616 ----------------------------------------- 1617 -- Validate_RCI_Subprogram_Declaration -- 1618 ----------------------------------------- 1619 1620 procedure Validate_RCI_Subprogram_Declaration (N : Node_Id) is 1621 K : constant Node_Kind := Nkind (N); 1622 Profile : List_Id; 1623 Id : constant Entity_Id := Defining_Entity (N); 1624 Param_Spec : Node_Id; 1625 Param_Type : Entity_Id; 1626 Error_Node : Node_Id := N; 1627 1628 begin 1629 -- This procedure enforces rules on subprogram and access to subprogram 1630 -- declarations in RCI units. These rules do not apply to expander 1631 -- generated routines, which are not remote subprograms. It is called: 1632 1633 -- 1. from Analyze_Subprogram_Declaration. 1634 -- 2. from Validate_Object_Declaration (access to subprogram). 1635 1636 if not (Comes_From_Source (N) 1637 and then In_RCI_Declaration 1638 and then not In_Private_Part (Scope (Id))) 1639 then 1640 return; 1641 end if; 1642 1643 if K = N_Subprogram_Declaration then 1644 Profile := Parameter_Specifications (Specification (N)); 1645 1646 else 1647 pragma Assert (K = N_Object_Declaration); 1648 1649 -- The above assertion is dubious, the visible declarations of an 1650 -- RCI unit never contain an object declaration, this should be an 1651 -- ACCESS-to-object declaration??? 1652 1653 if Nkind (Id) = N_Defining_Identifier 1654 and then Nkind (Parent (Etype (Id))) = N_Full_Type_Declaration 1655 and then Ekind (Etype (Id)) = E_Access_Subprogram_Type 1656 then 1657 Profile := 1658 Parameter_Specifications (Type_Definition (Parent (Etype (Id)))); 1659 else 1660 return; 1661 end if; 1662 end if; 1663 1664 -- Iterate through the parameter specification list, checking that 1665 -- no access parameter and no limited type parameter in the list. 1666 -- RM E.2.3(14). 1667 1668 if Present (Profile) then 1669 Param_Spec := First (Profile); 1670 while Present (Param_Spec) loop 1671 Param_Type := Etype (Defining_Identifier (Param_Spec)); 1672 1673 if Ekind (Param_Type) = E_Anonymous_Access_Type then 1674 if K = N_Subprogram_Declaration then 1675 Error_Node := Param_Spec; 1676 end if; 1677 1678 -- Report error only if declaration is in source program 1679 1680 if Comes_From_Source (Id) then 1681 Error_Msg_N 1682 ("subprogram in 'R'C'I unit cannot have access parameter", 1683 Error_Node); 1684 end if; 1685 1686 -- For a limited private type parameter, we check only the private 1687 -- declaration and ignore full type declaration, unless this is 1688 -- the only declaration for the type, e.g., as a limited record. 1689 1690 elsif No_External_Streaming (Param_Type) then 1691 if K = N_Subprogram_Declaration then 1692 Error_Node := Param_Spec; 1693 end if; 1694 1695 Error_Msg_NE 1696 ("formal of remote subprogram& " 1697 & "must support external streaming", 1698 Error_Node, Id); 1699 if Is_Limited_Type (Param_Type) then 1700 Explain_Limited_Type (Param_Type, Error_Node); 1701 end if; 1702 end if; 1703 1704 Next (Param_Spec); 1705 end loop; 1706 end if; 1707 1708 if Ekind (Id) = E_Function 1709 and then Ekind (Etype (Id)) = E_Anonymous_Access_Type 1710 and then Comes_From_Source (Id) 1711 then 1712 Error_Msg_N 1713 ("function in 'R'C'I unit cannot have access result", 1714 Error_Node); 1715 end if; 1716 end Validate_RCI_Subprogram_Declaration; 1717 1718 ---------------------------------------------------- 1719 -- Validate_Remote_Access_Object_Type_Declaration -- 1720 ---------------------------------------------------- 1721 1722 procedure Validate_Remote_Access_Object_Type_Declaration (T : Entity_Id) is 1723 Direct_Designated_Type : Entity_Id; 1724 Desig_Type : Entity_Id; 1725 1726 begin 1727 -- We are called from Analyze_Full_Type_Declaration, and the Nkind of 1728 -- the given node is N_Access_To_Object_Definition. 1729 1730 if not Comes_From_Source (T) 1731 or else (not In_RCI_Declaration and then not In_RT_Declaration) 1732 then 1733 return; 1734 end if; 1735 1736 -- An access definition in the private part of a package is not a 1737 -- remote access type. Restrictions related to external streaming 1738 -- support for non-remote access types are enforced elsewhere. Note 1739 -- that In_Private_Part is never set on type entities: check flag 1740 -- on enclosing scope. 1741 1742 if In_Private_Part (Scope (T)) then 1743 return; 1744 end if; 1745 1746 -- Check RCI or RT unit type declaration. It may not contain the 1747 -- declaration of an access-to-object type unless it is a general access 1748 -- type that designates a class-wide limited private type or subtype. 1749 -- There are also constraints on the primitive subprograms of the 1750 -- class-wide type (RM E.2.2(14), see Validate_RACW_Primitives). 1751 1752 if Ekind (T) /= E_General_Access_Type 1753 or else not Is_Class_Wide_Type (Designated_Type (T)) 1754 then 1755 if In_RCI_Declaration then 1756 Error_Msg_N 1757 ("error in access type in Remote_Call_Interface unit", T); 1758 else 1759 Error_Msg_N 1760 ("error in access type in Remote_Types unit", T); 1761 end if; 1762 1763 Error_Msg_N ("\must be general access to class-wide type", T); 1764 return; 1765 end if; 1766 1767 Direct_Designated_Type := Designated_Type (T); 1768 Desig_Type := Etype (Direct_Designated_Type); 1769 1770 -- Why is this check not in Validate_Remote_Access_To_Class_Wide_Type??? 1771 1772 if not Is_Valid_Remote_Object_Type (Desig_Type) then 1773 Error_Msg_N 1774 ("error in designated type of remote access to class-wide type", T); 1775 Error_Msg_N 1776 ("\must be tagged limited private or private extension", T); 1777 return; 1778 end if; 1779 end Validate_Remote_Access_Object_Type_Declaration; 1780 1781 ----------------------------------------------- 1782 -- Validate_Remote_Access_To_Class_Wide_Type -- 1783 ----------------------------------------------- 1784 1785 procedure Validate_Remote_Access_To_Class_Wide_Type (N : Node_Id) is 1786 K : constant Node_Kind := Nkind (N); 1787 PK : constant Node_Kind := Nkind (Parent (N)); 1788 E : Entity_Id; 1789 1790 begin 1791 -- This subprogram enforces the checks in (RM E.2.2(8)) for certain uses 1792 -- of class-wide limited private types. 1793 1794 -- Storage_Pool and Storage_Size are not defined for such types 1795 -- 1796 -- The expected type of allocator must not be such a type. 1797 1798 -- The actual parameter of generic instantiation must not be such a 1799 -- type if the formal parameter is of an access type. 1800 1801 -- On entry, there are several cases: 1802 1803 -- 1. called from sem_attr Analyze_Attribute where attribute name is 1804 -- either Storage_Pool or Storage_Size. 1805 1806 -- 2. called from exp_ch4 Expand_N_Allocator 1807 1808 -- 3. called from sem_ch4 Analyze_Explicit_Dereference 1809 1810 -- 4. called from sem_res Resolve_Actuals 1811 1812 if K = N_Attribute_Reference then 1813 E := Etype (Prefix (N)); 1814 1815 if Is_Remote_Access_To_Class_Wide_Type (E) then 1816 Error_Msg_N ("incorrect attribute of remote operand", N); 1817 return; 1818 end if; 1819 1820 elsif K = N_Allocator then 1821 E := Etype (N); 1822 1823 if Is_Remote_Access_To_Class_Wide_Type (E) then 1824 Error_Msg_N ("incorrect expected remote type of allocator", N); 1825 return; 1826 end if; 1827 1828 -- This subprogram also enforces the checks in E.2.2(13). A value of 1829 -- such type must not be dereferenced unless as controlling operand of 1830 -- a dispatching call. Explicit dereferences not coming from source are 1831 -- exempted from this checking because the expander produces them in 1832 -- some cases (such as for tag checks on dispatching calls with multiple 1833 -- controlling operands). However we do check in the case of an implicit 1834 -- dereference that is expanded to an explicit dereference (hence the 1835 -- test of whether Original_Node (N) comes from source). 1836 1837 elsif K = N_Explicit_Dereference 1838 and then Comes_From_Source (Original_Node (N)) 1839 then 1840 E := Etype (Prefix (N)); 1841 1842 -- If the class-wide type is not a remote one, the restrictions 1843 -- do not apply. 1844 1845 if not Is_Remote_Access_To_Class_Wide_Type (E) then 1846 return; 1847 end if; 1848 1849 -- If we have a true dereference that comes from source and that 1850 -- is a controlling argument for a dispatching call, accept it. 1851 1852 if Is_Actual_Parameter (N) and then Is_Controlling_Actual (N) then 1853 return; 1854 end if; 1855 1856 -- If we are just within a procedure or function call and the 1857 -- dereference has not been analyzed, return because this procedure 1858 -- will be called again from sem_res Resolve_Actuals. The same can 1859 -- apply in the case of dereference that is the prefix of a selected 1860 -- component, which can be a call given in prefixed form. 1861 1862 if (Is_Actual_Parameter (N) or else PK = N_Selected_Component) 1863 and then not Analyzed (N) 1864 then 1865 return; 1866 end if; 1867 1868 -- We must allow expanded code to generate a reference to the tag of 1869 -- the designated object (may be either the actual tag, or the stub 1870 -- tag in the case of a remote object). 1871 1872 if PK = N_Selected_Component 1873 and then Is_Tag (Entity (Selector_Name (Parent (N)))) 1874 then 1875 return; 1876 end if; 1877 1878 Error_Msg_N 1879 ("invalid dereference of a remote access-to-class-wide value", N); 1880 end if; 1881 end Validate_Remote_Access_To_Class_Wide_Type; 1882 1883 ------------------------------------------ 1884 -- Validate_Remote_Type_Type_Conversion -- 1885 ------------------------------------------ 1886 1887 procedure Validate_Remote_Type_Type_Conversion (N : Node_Id) is 1888 S : constant Entity_Id := Etype (N); 1889 E : constant Entity_Id := Etype (Expression (N)); 1890 1891 begin 1892 -- This test is required in the case where a conversion appears inside a 1893 -- normal package, it does not necessarily have to be inside an RCI, 1894 -- Remote_Types unit (RM E.2.2(9,12)). 1895 1896 if Is_Remote_Access_To_Subprogram_Type (E) 1897 and then not Is_Remote_Access_To_Subprogram_Type (S) 1898 then 1899 Error_Msg_N 1900 ("incorrect conversion of remote operand to local type", N); 1901 return; 1902 1903 elsif not Is_Remote_Access_To_Subprogram_Type (E) 1904 and then Is_Remote_Access_To_Subprogram_Type (S) 1905 then 1906 Error_Msg_N 1907 ("incorrect conversion of local operand to remote type", N); 1908 return; 1909 1910 elsif Is_Remote_Access_To_Class_Wide_Type (E) 1911 and then not Is_Remote_Access_To_Class_Wide_Type (S) 1912 then 1913 Error_Msg_N 1914 ("incorrect conversion of remote operand to local type", N); 1915 return; 1916 end if; 1917 1918 -- If a local access type is converted into a RACW type, then the 1919 -- current unit has a pointer that may now be exported to another 1920 -- partition. 1921 1922 if Is_Remote_Access_To_Class_Wide_Type (S) 1923 and then not Is_Remote_Access_To_Class_Wide_Type (E) 1924 then 1925 Set_Has_RACW (Current_Sem_Unit); 1926 end if; 1927 end Validate_Remote_Type_Type_Conversion; 1928 1929 ------------------------------- 1930 -- Validate_RT_RAT_Component -- 1931 ------------------------------- 1932 1933 procedure Validate_RT_RAT_Component (N : Node_Id) is 1934 Spec : constant Node_Id := Specification (N); 1935 Name_U : constant Entity_Id := Defining_Entity (Spec); 1936 Typ : Entity_Id; 1937 U_Typ : Entity_Id; 1938 First_Priv_Ent : constant Entity_Id := First_Private_Entity (Name_U); 1939 1940 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean; 1941 -- True if any stream attribute is available for Typ 1942 1943 --------------------------------- 1944 -- Stream_Attributes_Available -- 1945 --------------------------------- 1946 1947 function Stream_Attributes_Available (Typ : Entity_Id) return Boolean 1948 is 1949 begin 1950 return Stream_Attribute_Available (Typ, TSS_Stream_Read) 1951 or else 1952 Stream_Attribute_Available (Typ, TSS_Stream_Write) 1953 or else 1954 Stream_Attribute_Available (Typ, TSS_Stream_Input) 1955 or else 1956 Stream_Attribute_Available (Typ, TSS_Stream_Output); 1957 end Stream_Attributes_Available; 1958 1959 -- Start of processing for Validate_RT_RAT_Component 1960 1961 begin 1962 if not Is_Remote_Types (Name_U) then 1963 return; 1964 end if; 1965 1966 Typ := First_Entity (Name_U); 1967 while Present (Typ) and then Typ /= First_Priv_Ent loop 1968 U_Typ := Underlying_Type (Base_Type (Typ)); 1969 1970 if No (U_Typ) then 1971 U_Typ := Typ; 1972 end if; 1973 1974 if Comes_From_Source (Typ) and then Is_Type (Typ) 1975 and then Ekind (Typ) /= E_Incomplete_Type 1976 then 1977 -- Check that the type can be meaningfully transmitted to another 1978 -- partition (E.2.2(8)). 1979 1980 if (Ada_Version < Ada_2005 and then Has_Non_Remote_Access (U_Typ)) 1981 or else (Stream_Attributes_Available (Typ) 1982 and then No_External_Streaming (U_Typ)) 1983 then 1984 if Is_Non_Remote_Access_Type (Typ) then 1985 Error_Msg_N ("error in non-remote access type", U_Typ); 1986 else 1987 Error_Msg_N 1988 ("error in record type containing a component of a " & 1989 "non-remote access type", U_Typ); 1990 end if; 1991 1992 if Ada_Version >= Ada_2005 then 1993 Error_Msg_N 1994 ("\must have visible Read and Write attribute " & 1995 "definition clauses (RM E.2.2(8))", U_Typ); 1996 else 1997 Error_Msg_N 1998 ("\must have Read and Write attribute " & 1999 "definition clauses (RM E.2.2(8))", U_Typ); 2000 end if; 2001 end if; 2002 end if; 2003 2004 Next_Entity (Typ); 2005 end loop; 2006 end Validate_RT_RAT_Component; 2007 2008 ----------------------------------------- 2009 -- Validate_SP_Access_Object_Type_Decl -- 2010 ----------------------------------------- 2011 2012 procedure Validate_SP_Access_Object_Type_Decl (T : Entity_Id) is 2013 Direct_Designated_Type : Entity_Id; 2014 2015 function Has_Entry_Declarations (E : Entity_Id) return Boolean; 2016 -- Return true if the protected type designated by T has entry 2017 -- declarations. 2018 2019 ---------------------------- 2020 -- Has_Entry_Declarations -- 2021 ---------------------------- 2022 2023 function Has_Entry_Declarations (E : Entity_Id) return Boolean is 2024 Ety : Entity_Id; 2025 2026 begin 2027 if Nkind (Parent (E)) = N_Protected_Type_Declaration then 2028 Ety := First_Entity (E); 2029 while Present (Ety) loop 2030 if Ekind (Ety) = E_Entry then 2031 return True; 2032 end if; 2033 2034 Next_Entity (Ety); 2035 end loop; 2036 end if; 2037 2038 return False; 2039 end Has_Entry_Declarations; 2040 2041 -- Start of processing for Validate_SP_Access_Object_Type_Decl 2042 2043 begin 2044 -- We are called from Sem_Ch3.Analyze_Full_Type_Declaration, and the 2045 -- Nkind of the given entity is N_Access_To_Object_Definition. 2046 2047 if not Comes_From_Source (T) 2048 or else not In_Shared_Passive_Unit 2049 or else In_Subprogram_Task_Protected_Unit 2050 then 2051 return; 2052 end if; 2053 2054 -- Check Shared Passive unit. It should not contain the declaration 2055 -- of an access-to-object type whose designated type is a class-wide 2056 -- type, task type or protected type with entry (RM E.2.1(7)). 2057 2058 Direct_Designated_Type := Designated_Type (T); 2059 2060 if Ekind (Direct_Designated_Type) = E_Class_Wide_Type then 2061 Error_Msg_N 2062 ("invalid access-to-class-wide type in shared passive unit", T); 2063 return; 2064 2065 elsif Ekind (Direct_Designated_Type) in Task_Kind then 2066 Error_Msg_N 2067 ("invalid access-to-task type in shared passive unit", T); 2068 return; 2069 2070 elsif Ekind (Direct_Designated_Type) in Protected_Kind 2071 and then Has_Entry_Declarations (Direct_Designated_Type) 2072 then 2073 Error_Msg_N 2074 ("invalid access-to-protected type in shared passive unit", T); 2075 return; 2076 end if; 2077 end Validate_SP_Access_Object_Type_Decl; 2078 2079 --------------------------------- 2080 -- Validate_Static_Object_Name -- 2081 --------------------------------- 2082 2083 procedure Validate_Static_Object_Name (N : Node_Id) is 2084 E : Entity_Id; 2085 Val : Node_Id; 2086 2087 function Is_Primary (N : Node_Id) return Boolean; 2088 -- Determine whether node is syntactically a primary in an expression 2089 -- This function should probably be somewhere else ??? 2090 -- 2091 -- Also it does not do what it says, e.g if N is a binary operator 2092 -- whose parent is a binary operator, Is_Primary returns True ??? 2093 2094 ---------------- 2095 -- Is_Primary -- 2096 ---------------- 2097 2098 function Is_Primary (N : Node_Id) return Boolean is 2099 K : constant Node_Kind := Nkind (Parent (N)); 2100 2101 begin 2102 case K is 2103 when N_Aggregate 2104 | N_Component_Association 2105 | N_Index_Or_Discriminant_Constraint 2106 | N_Membership_Test 2107 | N_Op 2108 => 2109 return True; 2110 2111 when N_Attribute_Reference => 2112 declare 2113 Attr : constant Name_Id := Attribute_Name (Parent (N)); 2114 2115 begin 2116 return Attr /= Name_Address 2117 and then Attr /= Name_Access 2118 and then Attr /= Name_Unchecked_Access 2119 and then Attr /= Name_Unrestricted_Access; 2120 end; 2121 2122 when N_Indexed_Component => 2123 return N /= Prefix (Parent (N)) or else Is_Primary (Parent (N)); 2124 2125 when N_Qualified_Expression 2126 | N_Type_Conversion 2127 => 2128 return Is_Primary (Parent (N)); 2129 2130 when N_Assignment_Statement 2131 | N_Object_Declaration 2132 => 2133 return N = Expression (Parent (N)); 2134 2135 when N_Selected_Component => 2136 return Is_Primary (Parent (N)); 2137 2138 when others => 2139 return False; 2140 end case; 2141 end Is_Primary; 2142 2143 -- Start of processing for Validate_Static_Object_Name 2144 2145 begin 2146 if not In_Preelaborated_Unit 2147 or else not Comes_From_Source (N) 2148 or else In_Subprogram_Or_Concurrent_Unit 2149 or else Ekind (Current_Scope) = E_Block 2150 then 2151 return; 2152 2153 -- Filter out cases where primary is default in a component declaration, 2154 -- discriminant specification, or actual in a record type initialization 2155 -- call. 2156 2157 -- Initialization call of internal types 2158 2159 elsif Nkind (Parent (N)) = N_Procedure_Call_Statement then 2160 2161 if Present (Parent (Parent (N))) 2162 and then Nkind (Parent (Parent (N))) = N_Freeze_Entity 2163 then 2164 return; 2165 end if; 2166 2167 if Nkind (Name (Parent (N))) = N_Identifier 2168 and then not Comes_From_Source (Entity (Name (Parent (N)))) 2169 then 2170 return; 2171 end if; 2172 end if; 2173 2174 -- Error if the name is a primary in an expression. The parent must not 2175 -- be an operator, or a selected component or an indexed component that 2176 -- is itself a primary. Entities that are actuals do not need to be 2177 -- checked, because the call itself will be diagnosed. Entities in a 2178 -- generic unit or within a preanalyzed expression are not checked: 2179 -- only their use in executable code matters. 2180 2181 if Is_Primary (N) 2182 and then (not Inside_A_Generic 2183 or else Present (Enclosing_Generic_Body (N))) 2184 and then not In_Spec_Expression 2185 then 2186 if Ekind (Entity (N)) = E_Variable 2187 or else Ekind (Entity (N)) in Formal_Object_Kind 2188 then 2189 Flag_Non_Static_Expr 2190 ("non-static object name in preelaborated unit", N); 2191 2192 -- Give an error for a reference to a nonstatic constant, unless the 2193 -- constant is in another GNAT library unit that is preelaborable. 2194 2195 elsif Ekind (Entity (N)) = E_Constant 2196 and then not Is_Static_Expression (N) 2197 then 2198 E := Entity (N); 2199 Val := Constant_Value (E); 2200 2201 if In_Internal_Unit (N) 2202 and then 2203 Enclosing_Comp_Unit_Node (N) /= Enclosing_Comp_Unit_Node (E) 2204 and then (Is_Preelaborated (Scope (E)) 2205 or else Is_Pure (Scope (E)) 2206 or else (Present (Renamed_Object (E)) 2207 and then Is_Entity_Name (Renamed_Object (E)) 2208 and then 2209 (Is_Preelaborated 2210 (Scope (Renamed_Object (E))) 2211 or else 2212 Is_Pure 2213 (Scope (Renamed_Object (E)))))) 2214 then 2215 null; 2216 2217 -- If the value of the constant is a local variable that renames 2218 -- an aggregate, this is in itself legal. The aggregate may be 2219 -- expanded into a loop, but this does not affect preelaborability 2220 -- in itself. If some aggregate components are non-static, that is 2221 -- to say if they involve non static primaries, they will be 2222 -- flagged when analyzed. 2223 2224 elsif Present (Val) 2225 and then Is_Entity_Name (Val) 2226 and then Is_Array_Type (Etype (Val)) 2227 and then not Comes_From_Source (Val) 2228 and then Nkind (Original_Node (Val)) = N_Aggregate 2229 then 2230 null; 2231 2232 -- This is the error case 2233 2234 else 2235 -- In GNAT mode or Relaxed RM Semantic mode, this is just a 2236 -- warning, to allow it to be judiciously turned off. 2237 -- Otherwise it is a real error. 2238 2239 if GNAT_Mode or Relaxed_RM_Semantics then 2240 Error_Msg_N 2241 ("??non-static constant in preelaborated unit", N); 2242 else 2243 Flag_Non_Static_Expr 2244 ("non-static constant in preelaborated unit", N); 2245 end if; 2246 end if; 2247 end if; 2248 end if; 2249 end Validate_Static_Object_Name; 2250 2251end Sem_Cat; 2252