1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S E M _ C H 7 -- 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 26-- This package contains the routines to process package specifications and 27-- bodies. The most important semantic aspects of package processing are the 28-- handling of private and full declarations, and the construction of dispatch 29-- tables for tagged types. 30 31with Aspects; use Aspects; 32with Atree; use Atree; 33with Contracts; use Contracts; 34with Debug; use Debug; 35with Einfo; use Einfo; 36with Elists; use Elists; 37with Errout; use Errout; 38with Exp_Disp; use Exp_Disp; 39with Exp_Dist; use Exp_Dist; 40with Exp_Dbug; use Exp_Dbug; 41with Freeze; use Freeze; 42with Ghost; use Ghost; 43with Lib; use Lib; 44with Lib.Xref; use Lib.Xref; 45with Namet; use Namet; 46with Nmake; use Nmake; 47with Nlists; use Nlists; 48with Opt; use Opt; 49with Output; use Output; 50with Restrict; use Restrict; 51with Rtsfind; use Rtsfind; 52with Sem; use Sem; 53with Sem_Aux; use Sem_Aux; 54with Sem_Cat; use Sem_Cat; 55with Sem_Ch3; use Sem_Ch3; 56with Sem_Ch6; use Sem_Ch6; 57with Sem_Ch8; use Sem_Ch8; 58with Sem_Ch10; use Sem_Ch10; 59with Sem_Ch12; use Sem_Ch12; 60with Sem_Ch13; use Sem_Ch13; 61with Sem_Disp; use Sem_Disp; 62with Sem_Eval; use Sem_Eval; 63with Sem_Prag; use Sem_Prag; 64with Sem_Util; use Sem_Util; 65with Sem_Warn; use Sem_Warn; 66with Snames; use Snames; 67with Stand; use Stand; 68with Sinfo; use Sinfo; 69with Sinput; use Sinput; 70with Style; 71with Uintp; use Uintp; 72 73with GNAT.HTable; 74 75package body Sem_Ch7 is 76 77 ----------------------------------- 78 -- Handling private declarations -- 79 ----------------------------------- 80 81 -- The principle that each entity has a single defining occurrence clashes 82 -- with the presence of two separate definitions for private types: the 83 -- first is the private type declaration, and the second is the full type 84 -- declaration. It is important that all references to the type point to 85 -- the same defining occurrence, namely the first one. To enforce the two 86 -- separate views of the entity, the corresponding information is swapped 87 -- between the two declarations. Outside of the package, the defining 88 -- occurrence only contains the private declaration information, while in 89 -- the private part and the body of the package the defining occurrence 90 -- contains the full declaration. To simplify the swap, the defining 91 -- occurrence that currently holds the private declaration points to the 92 -- full declaration. During semantic processing the defining occurrence 93 -- also points to a list of private dependents, that is to say access types 94 -- or composite types whose designated types or component types are 95 -- subtypes or derived types of the private type in question. After the 96 -- full declaration has been seen, the private dependents are updated to 97 -- indicate that they have full definitions. 98 99 ----------------------- 100 -- Local Subprograms -- 101 ----------------------- 102 103 procedure Analyze_Package_Body_Helper (N : Node_Id); 104 -- Does all the real work of Analyze_Package_Body 105 106 procedure Check_Anonymous_Access_Types 107 (Spec_Id : Entity_Id; 108 P_Body : Node_Id); 109 -- If the spec of a package has a limited_with_clause, it may declare 110 -- anonymous access types whose designated type is a limited view, such an 111 -- anonymous access return type for a function. This access type cannot be 112 -- elaborated in the spec itself, but it may need an itype reference if it 113 -- is used within a nested scope. In that case the itype reference is 114 -- created at the beginning of the corresponding package body and inserted 115 -- before other body declarations. 116 117 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id); 118 -- Called upon entering the private part of a public child package and the 119 -- body of a nested package, to potentially declare certain inherited 120 -- subprograms that were inherited by types in the visible part, but whose 121 -- declaration was deferred because the parent operation was private and 122 -- not visible at that point. These subprograms are located by traversing 123 -- the visible part declarations looking for non-private type extensions 124 -- and then examining each of the primitive operations of such types to 125 -- find those that were inherited but declared with a special internal 126 -- name. Each such operation is now declared as an operation with a normal 127 -- name (using the name of the parent operation) and replaces the previous 128 -- implicit operation in the primitive operations list of the type. If the 129 -- inherited private operation has been overridden, then it's replaced by 130 -- the overriding operation. 131 132 procedure Install_Package_Entity (Id : Entity_Id); 133 -- Supporting procedure for Install_{Visible,Private}_Declarations. Places 134 -- one entity on its visibility chain, and recurses on the visible part if 135 -- the entity is an inner package. 136 137 function Is_Private_Base_Type (E : Entity_Id) return Boolean; 138 -- True for a private type that is not a subtype 139 140 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean; 141 -- If the private dependent is a private type whose full view is derived 142 -- from the parent type, its full properties are revealed only if we are in 143 -- the immediate scope of the private dependent. Should this predicate be 144 -- tightened further??? 145 146 function Requires_Completion_In_Body 147 (Id : Entity_Id; 148 Pack_Id : Entity_Id; 149 Do_Abstract_States : Boolean := False) return Boolean; 150 -- Subsidiary to routines Unit_Requires_Body and Unit_Requires_Body_Info. 151 -- Determine whether entity Id declared in package spec Pack_Id requires 152 -- completion in a package body. Flag Do_Abstract_Stats should be set when 153 -- abstract states are to be considered in the completion test. 154 155 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id); 156 -- Outputs info messages showing why package Pack_Id requires a body. The 157 -- caller has checked that the switch requesting this information is set, 158 -- and that the package does indeed require a body. 159 160 -------------------------- 161 -- Analyze_Package_Body -- 162 -------------------------- 163 164 procedure Analyze_Package_Body (N : Node_Id) is 165 Loc : constant Source_Ptr := Sloc (N); 166 167 begin 168 if Debug_Flag_C then 169 Write_Str ("==> package body "); 170 Write_Name (Chars (Defining_Entity (N))); 171 Write_Str (" from "); 172 Write_Location (Loc); 173 Write_Eol; 174 Indent; 175 end if; 176 177 -- The real work is split out into the helper, so it can do "return;" 178 -- without skipping the debug output. 179 180 Analyze_Package_Body_Helper (N); 181 182 if Debug_Flag_C then 183 Outdent; 184 Write_Str ("<== package body "); 185 Write_Name (Chars (Defining_Entity (N))); 186 Write_Str (" from "); 187 Write_Location (Loc); 188 Write_Eol; 189 end if; 190 end Analyze_Package_Body; 191 192 ------------------------------------------------------ 193 -- Analyze_Package_Body_Helper Data and Subprograms -- 194 ------------------------------------------------------ 195 196 Entity_Table_Size : constant := 4093; 197 -- Number of headers in hash table 198 199 subtype Entity_Header_Num is Integer range 0 .. Entity_Table_Size - 1; 200 -- Range of headers in hash table 201 202 function Node_Hash (Id : Entity_Id) return Entity_Header_Num; 203 -- Simple hash function for Entity_Ids 204 205 package Subprogram_Table is new GNAT.Htable.Simple_HTable 206 (Header_Num => Entity_Header_Num, 207 Element => Boolean, 208 No_Element => False, 209 Key => Entity_Id, 210 Hash => Node_Hash, 211 Equal => "="); 212 -- Hash table to record which subprograms are referenced. It is declared 213 -- at library level to avoid elaborating it for every call to Analyze. 214 215 package Traversed_Table is new GNAT.Htable.Simple_HTable 216 (Header_Num => Entity_Header_Num, 217 Element => Boolean, 218 No_Element => False, 219 Key => Node_Id, 220 Hash => Node_Hash, 221 Equal => "="); 222 -- Hash table to record which nodes we have traversed, so we can avoid 223 -- traversing the same nodes repeatedly. 224 225 ----------------- 226 -- Node_Hash -- 227 ----------------- 228 229 function Node_Hash (Id : Entity_Id) return Entity_Header_Num is 230 begin 231 return Entity_Header_Num (Id mod Entity_Table_Size); 232 end Node_Hash; 233 234 --------------------------------- 235 -- Analyze_Package_Body_Helper -- 236 --------------------------------- 237 238 -- WARNING: This routine manages Ghost regions. Return statements must be 239 -- replaced by gotos which jump to the end of the routine and restore the 240 -- Ghost mode. 241 242 procedure Analyze_Package_Body_Helper (N : Node_Id) is 243 procedure Hide_Public_Entities (Decls : List_Id); 244 -- Attempt to hide all public entities found in declarative list Decls 245 -- by resetting their Is_Public flag to False depending on whether the 246 -- entities are not referenced by inlined or generic bodies. This kind 247 -- of processing is a conservative approximation and will still leave 248 -- entities externally visible if the package is not simple enough. 249 250 procedure Install_Composite_Operations (P : Entity_Id); 251 -- Composite types declared in the current scope may depend on types 252 -- that were private at the point of declaration, and whose full view 253 -- is now in scope. Indicate that the corresponding operations on the 254 -- composite type are available. 255 256 -------------------------- 257 -- Hide_Public_Entities -- 258 -------------------------- 259 260 procedure Hide_Public_Entities (Decls : List_Id) is 261 function Has_Referencer 262 (Decls : List_Id; 263 In_Nested_Instance : Boolean; 264 Has_Outer_Referencer_Of_Non_Subprograms : Boolean) return Boolean; 265 -- A "referencer" is a construct which may reference a previous 266 -- declaration. Examine all declarations in list Decls in reverse 267 -- and determine whether one such referencer exists. All entities 268 -- in the range Last (Decls) .. Referencer are hidden from external 269 -- visibility. 270 271 function Scan_Subprogram_Ref (N : Node_Id) return Traverse_Result; 272 -- Determine whether a node denotes a reference to a subprogram 273 274 procedure Traverse_And_Scan_Subprogram_Refs is 275 new Traverse_Proc (Scan_Subprogram_Ref); 276 -- Subsidiary to routine Has_Referencer. Determine whether a node 277 -- contains references to a subprogram and record them. 278 -- WARNING: this is a very expensive routine as it performs a full 279 -- tree traversal. 280 281 procedure Scan_Subprogram_Refs (Node : Node_Id); 282 -- If we haven't already traversed Node, then mark it and traverse 283 -- it. 284 285 -------------------- 286 -- Has_Referencer -- 287 -------------------- 288 289 function Has_Referencer 290 (Decls : List_Id; 291 In_Nested_Instance : Boolean; 292 Has_Outer_Referencer_Of_Non_Subprograms : Boolean) return Boolean 293 is 294 Decl : Node_Id; 295 Decl_Id : Entity_Id; 296 Spec : Node_Id; 297 298 Has_Referencer_Of_Non_Subprograms : Boolean := 299 Has_Outer_Referencer_Of_Non_Subprograms; 300 -- Set if an inlined subprogram body was detected as a referencer. 301 -- In this case, we do not return True immediately but keep hiding 302 -- subprograms from external visibility. 303 304 begin 305 if No (Decls) then 306 return False; 307 end if; 308 309 -- Examine all declarations in reverse order, hiding all entities 310 -- from external visibility until a referencer has been found. The 311 -- algorithm recurses into nested packages. 312 313 Decl := Last (Decls); 314 while Present (Decl) loop 315 316 -- A stub is always considered a referencer 317 318 if Nkind (Decl) in N_Body_Stub then 319 return True; 320 321 -- Package declaration 322 323 elsif Nkind (Decl) = N_Package_Declaration then 324 Spec := Specification (Decl); 325 Decl_Id := Defining_Entity (Spec); 326 327 -- Inspect the declarations of a non-generic package to try 328 -- and hide more entities from external visibility. 329 330 if not Is_Generic_Unit (Decl_Id) then 331 if Has_Referencer (Private_Declarations (Spec), 332 In_Nested_Instance 333 or else 334 Is_Generic_Instance (Decl_Id), 335 Has_Referencer_Of_Non_Subprograms) 336 or else 337 Has_Referencer (Visible_Declarations (Spec), 338 In_Nested_Instance 339 or else 340 Is_Generic_Instance (Decl_Id), 341 Has_Referencer_Of_Non_Subprograms) 342 then 343 return True; 344 end if; 345 end if; 346 347 -- Package body 348 349 elsif Nkind (Decl) = N_Package_Body 350 and then Present (Corresponding_Spec (Decl)) 351 then 352 Decl_Id := Corresponding_Spec (Decl); 353 354 -- A generic package body is a referencer. It would seem 355 -- that we only have to consider generics that can be 356 -- exported, i.e. where the corresponding spec is the 357 -- spec of the current package, but because of nested 358 -- instantiations, a fully private generic body may export 359 -- other private body entities. Furthermore, regardless of 360 -- whether there was a previous inlined subprogram, (an 361 -- instantiation of) the generic package may reference any 362 -- entity declared before it. 363 364 if Is_Generic_Unit (Decl_Id) then 365 return True; 366 367 -- Inspect the declarations of a non-generic package body to 368 -- try and hide more entities from external visibility. 369 370 elsif Has_Referencer (Declarations (Decl), 371 In_Nested_Instance 372 or else 373 Is_Generic_Instance (Decl_Id), 374 Has_Referencer_Of_Non_Subprograms) 375 then 376 return True; 377 end if; 378 379 -- Subprogram body 380 381 elsif Nkind (Decl) = N_Subprogram_Body then 382 if Present (Corresponding_Spec (Decl)) then 383 Decl_Id := Corresponding_Spec (Decl); 384 385 -- A generic subprogram body acts as a referencer 386 387 if Is_Generic_Unit (Decl_Id) then 388 return True; 389 end if; 390 391 -- An inlined subprogram body acts as a referencer 392 393 -- Note that we test Has_Pragma_Inline here in addition 394 -- to Is_Inlined. We are doing this for a client, since 395 -- we are computing which entities should be public, and 396 -- it is the client who will decide if actual inlining 397 -- should occur, so we need to catch all cases where the 398 -- subprogram may be inlined by the client. 399 400 if Is_Inlined (Decl_Id) 401 or else Has_Pragma_Inline (Decl_Id) 402 then 403 Has_Referencer_Of_Non_Subprograms := True; 404 405 -- Inspect the statements of the subprogram body 406 -- to determine whether the body references other 407 -- subprograms. 408 409 Scan_Subprogram_Refs (Decl); 410 end if; 411 412 -- Otherwise this is a stand alone subprogram body 413 414 else 415 Decl_Id := Defining_Entity (Decl); 416 417 -- An inlined subprogram body acts as a referencer 418 419 if Is_Inlined (Decl_Id) 420 or else Has_Pragma_Inline (Decl_Id) 421 then 422 Has_Referencer_Of_Non_Subprograms := True; 423 424 -- Inspect the statements of the subprogram body 425 -- to determine whether the body references other 426 -- subprograms. 427 428 Scan_Subprogram_Refs (Decl); 429 430 -- Otherwise we can reset Is_Public right away 431 432 elsif not Subprogram_Table.Get (Decl_Id) then 433 Set_Is_Public (Decl_Id, False); 434 end if; 435 end if; 436 437 -- Freeze node 438 439 elsif Nkind (Decl) = N_Freeze_Entity then 440 declare 441 Discard : Boolean; 442 pragma Unreferenced (Discard); 443 begin 444 -- Inspect the actions to find references to subprograms. 445 -- We assume that the actions do not contain other kinds 446 -- of references and, therefore, we do not stop the scan 447 -- or set Has_Referencer_Of_Non_Subprograms here. Doing 448 -- it would pessimize common cases for which the actions 449 -- contain the declaration of an init procedure, since 450 -- such a procedure is automatically marked inline. 451 452 Discard := 453 Has_Referencer (Actions (Decl), 454 In_Nested_Instance, 455 Has_Referencer_Of_Non_Subprograms); 456 end; 457 458 -- Exceptions, objects and renamings do not need to be public 459 -- if they are not followed by a construct which can reference 460 -- and export them. Likewise for subprograms but we work harder 461 -- for them to see whether they are referenced on an individual 462 -- basis by looking into the table of referenced subprograms. 463 -- But we cannot say anything for entities declared in nested 464 -- instances because instantiations are not done yet so the 465 -- bodies are not visible and could contain references to them. 466 elsif Nkind_In (Decl, N_Exception_Declaration, 467 N_Object_Declaration, 468 N_Object_Renaming_Declaration, 469 N_Subprogram_Declaration, 470 N_Subprogram_Renaming_Declaration) 471 then 472 Decl_Id := Defining_Entity (Decl); 473 474 if not In_Nested_Instance 475 and then not Is_Imported (Decl_Id) 476 and then not Is_Exported (Decl_Id) 477 and then No (Interface_Name (Decl_Id)) 478 and then 479 ((Nkind (Decl) /= N_Subprogram_Declaration 480 and then not Has_Referencer_Of_Non_Subprograms) 481 or else (Nkind (Decl) = N_Subprogram_Declaration 482 and then not Subprogram_Table.Get (Decl_Id))) 483 then 484 Set_Is_Public (Decl_Id, False); 485 end if; 486 487 -- For a subprogram renaming, if the entity is referenced, 488 -- then so is the renamed subprogram. But there is an issue 489 -- with generic bodies because instantiations are not done 490 -- yet and, therefore, cannot be scanned for referencers. 491 -- That's why we use an approximation and test that we have 492 -- at least one subprogram referenced by an inlined body 493 -- instead of precisely the entity of this renaming. 494 495 if Nkind (Decl) = N_Subprogram_Renaming_Declaration 496 and then Subprogram_Table.Get_First 497 and then Is_Entity_Name (Name (Decl)) 498 and then Present (Entity (Name (Decl))) 499 and then Is_Subprogram (Entity (Name (Decl))) 500 then 501 Subprogram_Table.Set (Entity (Name (Decl)), True); 502 end if; 503 end if; 504 505 Prev (Decl); 506 end loop; 507 508 return Has_Referencer_Of_Non_Subprograms; 509 end Has_Referencer; 510 511 ------------------------- 512 -- Scan_Subprogram_Ref -- 513 ------------------------- 514 515 function Scan_Subprogram_Ref (N : Node_Id) return Traverse_Result is 516 begin 517 -- Detect a reference of the form 518 -- Subp_Call 519 520 if Nkind (N) in N_Subprogram_Call 521 and then Is_Entity_Name (Name (N)) 522 and then Present (Entity (Name (N))) 523 and then Is_Subprogram (Entity (Name (N))) 524 then 525 Subprogram_Table.Set (Entity (Name (N)), True); 526 527 -- Detect a reference of the form 528 -- Subp'Some_Attribute 529 530 elsif Nkind (N) = N_Attribute_Reference 531 and then Is_Entity_Name (Prefix (N)) 532 and then Present (Entity (Prefix (N))) 533 and then Is_Subprogram (Entity (Prefix (N))) 534 then 535 Subprogram_Table.Set (Entity (Prefix (N)), True); 536 537 -- Constants can be substituted by their value in gigi, which may 538 -- contain a reference, so scan the value recursively. 539 540 elsif Is_Entity_Name (N) 541 and then Present (Entity (N)) 542 and then Ekind (Entity (N)) = E_Constant 543 then 544 declare 545 Val : constant Node_Id := Constant_Value (Entity (N)); 546 begin 547 if Present (Val) 548 and then not Compile_Time_Known_Value (Val) 549 then 550 Scan_Subprogram_Refs (Val); 551 end if; 552 end; 553 end if; 554 555 return OK; 556 end Scan_Subprogram_Ref; 557 558 -------------------------- 559 -- Scan_Subprogram_Refs -- 560 -------------------------- 561 562 procedure Scan_Subprogram_Refs (Node : Node_Id) is 563 begin 564 if not Traversed_Table.Get (Node) then 565 Traversed_Table.Set (Node, True); 566 Traverse_And_Scan_Subprogram_Refs (Node); 567 end if; 568 end Scan_Subprogram_Refs; 569 570 -- Local variables 571 572 Discard : Boolean; 573 pragma Unreferenced (Discard); 574 575 -- Start of processing for Hide_Public_Entities 576 577 begin 578 -- The algorithm examines the top level declarations of a package 579 -- body in reverse looking for a construct that may export entities 580 -- declared prior to it. If such a scenario is encountered, then all 581 -- entities in the range Last (Decls) .. construct are hidden from 582 -- external visibility. Consider: 583 584 -- package Pack is 585 -- generic 586 -- package Gen is 587 -- end Gen; 588 -- end Pack; 589 590 -- package body Pack is 591 -- External_Obj : ...; -- (1) 592 593 -- package body Gen is -- (2) 594 -- ... External_Obj ... -- (3) 595 -- end Gen; 596 597 -- Local_Obj : ...; -- (4) 598 -- end Pack; 599 600 -- In this example Local_Obj (4) must not be externally visible as 601 -- it cannot be exported by anything in Pack. The body of generic 602 -- package Gen (2) on the other hand acts as a "referencer" and may 603 -- export anything declared before it. Since the compiler does not 604 -- perform flow analysis, it is not possible to determine precisely 605 -- which entities will be exported when Gen is instantiated. In the 606 -- example above External_Obj (1) is exported at (3), but this may 607 -- not always be the case. The algorithm takes a conservative stance 608 -- and leaves entity External_Obj public. 609 610 -- This very conservative algorithm is supplemented by a more precise 611 -- processing for inlined bodies. For them, we traverse the syntactic 612 -- tree and record which subprograms are actually referenced from it. 613 -- This makes it possible to compute a much smaller set of externally 614 -- visible subprograms in the absence of generic bodies, which can 615 -- have a significant impact on the inlining decisions made in the 616 -- back end and the removal of out-of-line bodies from the object 617 -- code. We do it only for inlined bodies because they are supposed 618 -- to be reasonably small and tree traversal is very expensive. 619 620 -- Note that even this special processing is not optimal for inlined 621 -- bodies, because we treat all inlined subprograms alike. An optimal 622 -- algorithm would require computing the transitive closure of the 623 -- inlined subprograms that can really be referenced from other units 624 -- in the source code. 625 626 -- We could extend this processing for inlined bodies and record all 627 -- entities, not just subprograms, referenced from them, which would 628 -- make it possible to compute a much smaller set of all externally 629 -- visible entities in the absence of generic bodies. But this would 630 -- mean implementing a more thorough tree traversal of the bodies, 631 -- i.e. not just syntactic, and the gain would very likely be worth 632 -- neither the hassle nor the slowdown of the compiler. 633 634 -- Finally, an important thing to be aware of is that, at this point, 635 -- instantiations are not done yet so we cannot directly see inlined 636 -- bodies coming from them. That's not catastrophic because only the 637 -- actual parameters of the instantiations matter here, and they are 638 -- present in the declarations list of the instantiated packages. 639 640 Traversed_Table.Reset; 641 Subprogram_Table.Reset; 642 Discard := Has_Referencer (Decls, False, False); 643 end Hide_Public_Entities; 644 645 ---------------------------------- 646 -- Install_Composite_Operations -- 647 ---------------------------------- 648 649 procedure Install_Composite_Operations (P : Entity_Id) is 650 Id : Entity_Id; 651 652 begin 653 Id := First_Entity (P); 654 while Present (Id) loop 655 if Is_Type (Id) 656 and then (Is_Limited_Composite (Id) 657 or else Is_Private_Composite (Id)) 658 and then No (Private_Component (Id)) 659 then 660 Set_Is_Limited_Composite (Id, False); 661 Set_Is_Private_Composite (Id, False); 662 end if; 663 664 Next_Entity (Id); 665 end loop; 666 end Install_Composite_Operations; 667 668 -- Local variables 669 670 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode; 671 Saved_IGR : constant Node_Id := Ignored_Ghost_Region; 672 Saved_EA : constant Boolean := Expander_Active; 673 Saved_ISMP : constant Boolean := 674 Ignore_SPARK_Mode_Pragmas_In_Instance; 675 -- Save the Ghost and SPARK mode-related data to restore on exit 676 677 Body_Id : Entity_Id; 678 HSS : Node_Id; 679 Last_Spec_Entity : Entity_Id; 680 New_N : Node_Id; 681 Pack_Decl : Node_Id; 682 Spec_Id : Entity_Id; 683 684 -- Start of processing for Analyze_Package_Body_Helper 685 686 begin 687 -- Find corresponding package specification, and establish the current 688 -- scope. The visible defining entity for the package is the defining 689 -- occurrence in the spec. On exit from the package body, all body 690 -- declarations are attached to the defining entity for the body, but 691 -- the later is never used for name resolution. In this fashion there 692 -- is only one visible entity that denotes the package. 693 694 -- Set Body_Id. Note that this will be reset to point to the generic 695 -- copy later on in the generic case. 696 697 Body_Id := Defining_Entity (N); 698 699 -- Body is body of package instantiation. Corresponding spec has already 700 -- been set. 701 702 if Present (Corresponding_Spec (N)) then 703 Spec_Id := Corresponding_Spec (N); 704 Pack_Decl := Unit_Declaration_Node (Spec_Id); 705 706 else 707 Spec_Id := Current_Entity_In_Scope (Defining_Entity (N)); 708 709 if Present (Spec_Id) 710 and then Is_Package_Or_Generic_Package (Spec_Id) 711 then 712 Pack_Decl := Unit_Declaration_Node (Spec_Id); 713 714 if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then 715 Error_Msg_N ("cannot supply body for package renaming", N); 716 return; 717 718 elsif Present (Corresponding_Body (Pack_Decl)) then 719 Error_Msg_N ("redefinition of package body", N); 720 return; 721 end if; 722 723 else 724 Error_Msg_N ("missing specification for package body", N); 725 return; 726 end if; 727 728 if Is_Package_Or_Generic_Package (Spec_Id) 729 and then (Scope (Spec_Id) = Standard_Standard 730 or else Is_Child_Unit (Spec_Id)) 731 and then not Unit_Requires_Body (Spec_Id) 732 then 733 if Ada_Version = Ada_83 then 734 Error_Msg_N 735 ("optional package body (not allowed in Ada 95)??", N); 736 else 737 Error_Msg_N ("spec of this package does not allow a body", N); 738 end if; 739 end if; 740 end if; 741 742 -- A [generic] package body freezes the contract of the nearest 743 -- enclosing package body and all other contracts encountered in 744 -- the same declarative part up to and excluding the package body: 745 746 -- package body Nearest_Enclosing_Package 747 -- with Refined_State => (State => Constit) 748 -- is 749 -- Constit : ...; 750 751 -- package body Freezes_Enclosing_Package_Body 752 -- with Refined_State => (State_2 => Constit_2) 753 -- is 754 -- Constit_2 : ...; 755 756 -- procedure Proc 757 -- with Refined_Depends => (Input => (Constit, Constit_2)) ... 758 759 -- This ensures that any annotations referenced by the contract of a 760 -- [generic] subprogram body declared within the current package body 761 -- are available. This form of freezing is decoupled from the usual 762 -- Freeze_xxx mechanism because it must also work in the context of 763 -- generics where normal freezing is disabled. 764 765 -- Only bodies coming from source should cause this type of freezing. 766 -- Instantiated generic bodies are excluded because their processing is 767 -- performed in a separate compilation pass which lacks enough semantic 768 -- information with respect to contract analysis. It is safe to suppress 769 -- the freezing of contracts in this case because this action already 770 -- took place at the end of the enclosing declarative part. 771 772 if Comes_From_Source (N) 773 and then not Is_Generic_Instance (Spec_Id) 774 then 775 Freeze_Previous_Contracts (N); 776 end if; 777 778 -- A package body is Ghost when the corresponding spec is Ghost. Set 779 -- the mode now to ensure that any nodes generated during analysis and 780 -- expansion are properly flagged as ignored Ghost. 781 782 Mark_And_Set_Ghost_Body (N, Spec_Id); 783 784 -- Deactivate expansion inside the body of ignored Ghost entities, 785 -- as this code will ultimately be ignored. This avoids requiring the 786 -- presence of run-time units which are not needed. Only do this for 787 -- user entities, as internally generated entitities might still need 788 -- to be expanded (e.g. those generated for types). 789 790 if Present (Ignored_Ghost_Region) 791 and then Comes_From_Source (Body_Id) 792 then 793 Expander_Active := False; 794 end if; 795 796 -- If the body completes the initial declaration of a compilation unit 797 -- which is subject to pragma Elaboration_Checks, set the model of the 798 -- pragma because it applies to all parts of the unit. 799 800 Install_Elaboration_Model (Spec_Id); 801 802 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id)); 803 Style.Check_Identifier (Body_Id, Spec_Id); 804 805 if Is_Child_Unit (Spec_Id) then 806 if Nkind (Parent (N)) /= N_Compilation_Unit then 807 Error_Msg_NE 808 ("body of child unit& cannot be an inner package", N, Spec_Id); 809 end if; 810 811 Set_Is_Child_Unit (Body_Id); 812 end if; 813 814 -- Generic package case 815 816 if Ekind (Spec_Id) = E_Generic_Package then 817 818 -- Disable expansion and perform semantic analysis on copy. The 819 -- unannotated body will be used in all instantiations. 820 821 Body_Id := Defining_Entity (N); 822 Set_Ekind (Body_Id, E_Package_Body); 823 Set_Scope (Body_Id, Scope (Spec_Id)); 824 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id)); 825 Set_Body_Entity (Spec_Id, Body_Id); 826 Set_Spec_Entity (Body_Id, Spec_Id); 827 828 New_N := Copy_Generic_Node (N, Empty, Instantiating => False); 829 Rewrite (N, New_N); 830 831 -- Once the contents of the generic copy and the template are 832 -- swapped, do the same for their respective aspect specifications. 833 834 Exchange_Aspects (N, New_N); 835 836 -- Collect all contract-related source pragmas found within the 837 -- template and attach them to the contract of the package body. 838 -- This contract is used in the capture of global references within 839 -- annotations. 840 841 Create_Generic_Contract (N); 842 843 -- Update Body_Id to point to the copied node for the remainder of 844 -- the processing. 845 846 Body_Id := Defining_Entity (N); 847 Start_Generic; 848 end if; 849 850 -- The Body_Id is that of the copied node in the generic case, the 851 -- current node otherwise. Note that N was rewritten above, so we must 852 -- be sure to get the latest Body_Id value. 853 854 Set_Ekind (Body_Id, E_Package_Body); 855 Set_Body_Entity (Spec_Id, Body_Id); 856 Set_Spec_Entity (Body_Id, Spec_Id); 857 858 -- Defining name for the package body is not a visible entity: Only the 859 -- defining name for the declaration is visible. 860 861 Set_Etype (Body_Id, Standard_Void_Type); 862 Set_Scope (Body_Id, Scope (Spec_Id)); 863 Set_Corresponding_Spec (N, Spec_Id); 864 Set_Corresponding_Body (Pack_Decl, Body_Id); 865 866 -- The body entity is not used for semantics or code generation, but 867 -- it is attached to the entity list of the enclosing scope to simplify 868 -- the listing of back-annotations for the types it main contain. 869 870 if Scope (Spec_Id) /= Standard_Standard then 871 Append_Entity (Body_Id, Scope (Spec_Id)); 872 end if; 873 874 -- Indicate that we are currently compiling the body of the package 875 876 Set_In_Package_Body (Spec_Id); 877 Set_Has_Completion (Spec_Id); 878 Last_Spec_Entity := Last_Entity (Spec_Id); 879 880 if Has_Aspects (N) then 881 Analyze_Aspect_Specifications (N, Body_Id); 882 end if; 883 884 Push_Scope (Spec_Id); 885 886 -- Set SPARK_Mode only for non-generic package 887 888 if Ekind (Spec_Id) = E_Package then 889 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma); 890 Set_SPARK_Aux_Pragma (Body_Id, SPARK_Mode_Pragma); 891 Set_SPARK_Pragma_Inherited (Body_Id); 892 Set_SPARK_Aux_Pragma_Inherited (Body_Id); 893 894 -- A package body may be instantiated or inlined at a later pass. 895 -- Restore the state of Ignore_SPARK_Mode_Pragmas_In_Instance when 896 -- it applied to the package spec. 897 898 if Ignore_SPARK_Mode_Pragmas (Spec_Id) then 899 Ignore_SPARK_Mode_Pragmas_In_Instance := True; 900 end if; 901 end if; 902 903 Set_Categorization_From_Pragmas (N); 904 905 Install_Visible_Declarations (Spec_Id); 906 Install_Private_Declarations (Spec_Id); 907 Install_Private_With_Clauses (Spec_Id); 908 Install_Composite_Operations (Spec_Id); 909 910 Check_Anonymous_Access_Types (Spec_Id, N); 911 912 if Ekind (Spec_Id) = E_Generic_Package then 913 Set_Use (Generic_Formal_Declarations (Pack_Decl)); 914 end if; 915 916 Set_Use (Visible_Declarations (Specification (Pack_Decl))); 917 Set_Use (Private_Declarations (Specification (Pack_Decl))); 918 919 -- This is a nested package, so it may be necessary to declare certain 920 -- inherited subprograms that are not yet visible because the parent 921 -- type's subprograms are now visible. 922 923 if Ekind (Scope (Spec_Id)) = E_Package 924 and then Scope (Spec_Id) /= Standard_Standard 925 then 926 Declare_Inherited_Private_Subprograms (Spec_Id); 927 end if; 928 929 if Present (Declarations (N)) then 930 Analyze_Declarations (Declarations (N)); 931 Inspect_Deferred_Constant_Completion (Declarations (N)); 932 end if; 933 934 -- Verify that the SPARK_Mode of the body agrees with that of its spec 935 936 if Present (SPARK_Pragma (Body_Id)) then 937 if Present (SPARK_Aux_Pragma (Spec_Id)) then 938 if Get_SPARK_Mode_From_Annotation (SPARK_Aux_Pragma (Spec_Id)) = 939 Off 940 and then 941 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On 942 then 943 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id)); 944 Error_Msg_N ("incorrect application of SPARK_Mode#", N); 945 Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id)); 946 Error_Msg_NE 947 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id); 948 end if; 949 950 else 951 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id)); 952 Error_Msg_N ("incorrect application of SPARK_Mode#", N); 953 Error_Msg_Sloc := Sloc (Spec_Id); 954 Error_Msg_NE 955 ("\no value was set for SPARK_Mode on & #", N, Spec_Id); 956 end if; 957 end if; 958 959 -- Analyze_Declarations has caused freezing of all types. Now generate 960 -- bodies for RACW primitives and stream attributes, if any. 961 962 if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then 963 964 -- Attach subprogram bodies to support RACWs declared in spec 965 966 Append_RACW_Bodies (Declarations (N), Spec_Id); 967 Analyze_List (Declarations (N)); 968 end if; 969 970 HSS := Handled_Statement_Sequence (N); 971 972 if Present (HSS) then 973 Process_End_Label (HSS, 't', Spec_Id); 974 Analyze (HSS); 975 976 -- Check that elaboration code in a preelaborable package body is 977 -- empty other than null statements and labels (RM 10.2.1(6)). 978 979 Validate_Null_Statement_Sequence (N); 980 end if; 981 982 Validate_Categorization_Dependency (N, Spec_Id); 983 Check_Completion (Body_Id); 984 985 -- Generate start of body reference. Note that we do this fairly late, 986 -- because the call will use In_Extended_Main_Source_Unit as a check, 987 -- and we want to make sure that Corresponding_Stub links are set 988 989 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False); 990 991 -- For a generic package, collect global references and mark them on 992 -- the original body so that they are not resolved again at the point 993 -- of instantiation. 994 995 if Ekind (Spec_Id) /= E_Package then 996 Save_Global_References (Original_Node (N)); 997 End_Generic; 998 end if; 999 1000 -- The entities of the package body have so far been chained onto the 1001 -- declaration chain for the spec. That's been fine while we were in the 1002 -- body, since we wanted them to be visible, but now that we are leaving 1003 -- the package body, they are no longer visible, so we remove them from 1004 -- the entity chain of the package spec entity, and copy them to the 1005 -- entity chain of the package body entity, where they will never again 1006 -- be visible. 1007 1008 if Present (Last_Spec_Entity) then 1009 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity)); 1010 Set_Next_Entity (Last_Spec_Entity, Empty); 1011 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id)); 1012 Set_Last_Entity (Spec_Id, Last_Spec_Entity); 1013 1014 else 1015 Set_First_Entity (Body_Id, First_Entity (Spec_Id)); 1016 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id)); 1017 Set_First_Entity (Spec_Id, Empty); 1018 Set_Last_Entity (Spec_Id, Empty); 1019 end if; 1020 1021 Update_Use_Clause_Chain; 1022 End_Package_Scope (Spec_Id); 1023 1024 -- All entities declared in body are not visible 1025 1026 declare 1027 E : Entity_Id; 1028 1029 begin 1030 E := First_Entity (Body_Id); 1031 while Present (E) loop 1032 Set_Is_Immediately_Visible (E, False); 1033 Set_Is_Potentially_Use_Visible (E, False); 1034 Set_Is_Hidden (E); 1035 1036 -- Child units may appear on the entity list (e.g. if they appear 1037 -- in the context of a subunit) but they are not body entities. 1038 1039 if not Is_Child_Unit (E) then 1040 Set_Is_Package_Body_Entity (E); 1041 end if; 1042 1043 Next_Entity (E); 1044 end loop; 1045 end; 1046 1047 Check_References (Body_Id); 1048 1049 -- For a generic unit, check that the formal parameters are referenced, 1050 -- and that local variables are used, as for regular packages. 1051 1052 if Ekind (Spec_Id) = E_Generic_Package then 1053 Check_References (Spec_Id); 1054 end if; 1055 1056 -- At this point all entities of the package body are externally visible 1057 -- to the linker as their Is_Public flag is set to True. This proactive 1058 -- approach is necessary because an inlined or a generic body for which 1059 -- code is generated in other units may need to see these entities. Cut 1060 -- down the number of global symbols that do not neet public visibility 1061 -- as this has two beneficial effects: 1062 -- (1) It makes the compilation process more efficient. 1063 -- (2) It gives the code generator more leeway to optimize within each 1064 -- unit, especially subprograms. 1065 1066 -- This is done only for top-level library packages or child units as 1067 -- the algorithm does a top-down traversal of the package body. 1068 1069 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id)) 1070 and then not Is_Generic_Unit (Spec_Id) 1071 then 1072 Hide_Public_Entities (Declarations (N)); 1073 end if; 1074 1075 -- If expander is not active, then here is where we turn off the 1076 -- In_Package_Body flag, otherwise it is turned off at the end of the 1077 -- corresponding expansion routine. If this is an instance body, we need 1078 -- to qualify names of local entities, because the body may have been 1079 -- compiled as a preliminary to another instantiation. 1080 1081 if not Expander_Active then 1082 Set_In_Package_Body (Spec_Id, False); 1083 1084 if Is_Generic_Instance (Spec_Id) 1085 and then Operating_Mode = Generate_Code 1086 then 1087 Qualify_Entity_Names (N); 1088 end if; 1089 end if; 1090 1091 if Present (Ignored_Ghost_Region) then 1092 Expander_Active := Saved_EA; 1093 end if; 1094 1095 Ignore_SPARK_Mode_Pragmas_In_Instance := Saved_ISMP; 1096 Restore_Ghost_Region (Saved_GM, Saved_IGR); 1097 end Analyze_Package_Body_Helper; 1098 1099 --------------------------------- 1100 -- Analyze_Package_Declaration -- 1101 --------------------------------- 1102 1103 procedure Analyze_Package_Declaration (N : Node_Id) is 1104 Id : constant Node_Id := Defining_Entity (N); 1105 1106 Is_Comp_Unit : constant Boolean := 1107 Nkind (Parent (N)) = N_Compilation_Unit; 1108 1109 Body_Required : Boolean; 1110 -- True when this package declaration requires a corresponding body 1111 1112 begin 1113 if Debug_Flag_C then 1114 Write_Str ("==> package spec "); 1115 Write_Name (Chars (Id)); 1116 Write_Str (" from "); 1117 Write_Location (Sloc (N)); 1118 Write_Eol; 1119 Indent; 1120 end if; 1121 1122 Generate_Definition (Id); 1123 Enter_Name (Id); 1124 Set_Ekind (Id, E_Package); 1125 Set_Etype (Id, Standard_Void_Type); 1126 1127 -- Set SPARK_Mode from context 1128 1129 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma); 1130 Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma); 1131 Set_SPARK_Pragma_Inherited (Id); 1132 Set_SPARK_Aux_Pragma_Inherited (Id); 1133 1134 -- Save the state of flag Ignore_SPARK_Mode_Pragmas_In_Instance in case 1135 -- the body of this package is instantiated or inlined later and out of 1136 -- context. The body uses this attribute to restore the value of the 1137 -- global flag. 1138 1139 if Ignore_SPARK_Mode_Pragmas_In_Instance then 1140 Set_Ignore_SPARK_Mode_Pragmas (Id); 1141 end if; 1142 1143 -- Analyze aspect specifications immediately, since we need to recognize 1144 -- things like Pure early enough to diagnose violations during analysis. 1145 1146 if Has_Aspects (N) then 1147 Analyze_Aspect_Specifications (N, Id); 1148 end if; 1149 1150 -- Ada 2005 (AI-217): Check if the package has been illegally named in 1151 -- a limited-with clause of its own context. In this case the error has 1152 -- been previously notified by Analyze_Context. 1153 1154 -- limited with Pkg; -- ERROR 1155 -- package Pkg is ... 1156 1157 if From_Limited_With (Id) then 1158 return; 1159 end if; 1160 1161 Push_Scope (Id); 1162 1163 Set_Is_Pure (Id, Is_Pure (Enclosing_Lib_Unit_Entity)); 1164 Set_Categorization_From_Pragmas (N); 1165 1166 Analyze (Specification (N)); 1167 Validate_Categorization_Dependency (N, Id); 1168 1169 -- Determine whether the package requires a body. Abstract states are 1170 -- intentionally ignored because they do require refinement which can 1171 -- only come in a body, but at the same time they do not force the need 1172 -- for a body on their own (SPARK RM 7.1.4(4) and 7.2.2(3)). 1173 1174 Body_Required := Unit_Requires_Body (Id); 1175 1176 if not Body_Required then 1177 1178 -- If the package spec does not require an explicit body, then there 1179 -- are not entities requiring completion in the language sense. Call 1180 -- Check_Completion now to ensure that nested package declarations 1181 -- that require an implicit body get one. (In the case where a body 1182 -- is required, Check_Completion is called at the end of the body's 1183 -- declarative part.) 1184 1185 Check_Completion; 1186 1187 -- If the package spec does not require an explicit body, then all 1188 -- abstract states declared in nested packages cannot possibly get 1189 -- a proper refinement (SPARK RM 7.2.2(3)). This check is performed 1190 -- only when the compilation unit is the main unit to allow for 1191 -- modular SPARK analysis where packages do not necessarily have 1192 -- bodies. 1193 1194 if Is_Comp_Unit then 1195 Check_State_Refinements 1196 (Context => N, 1197 Is_Main_Unit => Parent (N) = Cunit (Main_Unit)); 1198 end if; 1199 end if; 1200 1201 -- Set Body_Required indication on the compilation unit node 1202 1203 if Is_Comp_Unit then 1204 Set_Body_Required (Parent (N), Body_Required); 1205 1206 if Legacy_Elaboration_Checks and not Body_Required then 1207 Set_Suppress_Elaboration_Warnings (Id); 1208 end if; 1209 end if; 1210 1211 End_Package_Scope (Id); 1212 1213 -- For the declaration of a library unit that is a remote types package, 1214 -- check legality rules regarding availability of stream attributes for 1215 -- types that contain non-remote access values. This subprogram performs 1216 -- visibility tests that rely on the fact that we have exited the scope 1217 -- of Id. 1218 1219 if Is_Comp_Unit then 1220 Validate_RT_RAT_Component (N); 1221 end if; 1222 1223 if Debug_Flag_C then 1224 Outdent; 1225 Write_Str ("<== package spec "); 1226 Write_Name (Chars (Id)); 1227 Write_Str (" from "); 1228 Write_Location (Sloc (N)); 1229 Write_Eol; 1230 end if; 1231 end Analyze_Package_Declaration; 1232 1233 ----------------------------------- 1234 -- Analyze_Package_Specification -- 1235 ----------------------------------- 1236 1237 -- Note that this code is shared for the analysis of generic package specs 1238 -- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details). 1239 1240 procedure Analyze_Package_Specification (N : Node_Id) is 1241 Id : constant Entity_Id := Defining_Entity (N); 1242 Orig_Decl : constant Node_Id := Original_Node (Parent (N)); 1243 Vis_Decls : constant List_Id := Visible_Declarations (N); 1244 Priv_Decls : constant List_Id := Private_Declarations (N); 1245 E : Entity_Id; 1246 L : Entity_Id; 1247 Public_Child : Boolean; 1248 1249 Private_With_Clauses_Installed : Boolean := False; 1250 -- In Ada 2005, private with_clauses are visible in the private part 1251 -- of a nested package, even if it appears in the public part of the 1252 -- enclosing package. This requires a separate step to install these 1253 -- private_with_clauses, and remove them at the end of the nested 1254 -- package. 1255 1256 procedure Check_One_Tagged_Type_Or_Extension_At_Most; 1257 -- Issue an error in SPARK mode if a package specification contains 1258 -- more than one tagged type or type extension. 1259 1260 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id); 1261 -- Clears constant indications (Never_Set_In_Source, Constant_Value, and 1262 -- Is_True_Constant) on all variables that are entities of Id, and on 1263 -- the chain whose first element is FE. A recursive call is made for all 1264 -- packages and generic packages. 1265 1266 procedure Generate_Parent_References; 1267 -- For a child unit, generate references to parent units, for 1268 -- GPS navigation purposes. 1269 1270 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean; 1271 -- Child and Unit are entities of compilation units. True if Child 1272 -- is a public child of Parent as defined in 10.1.1 1273 1274 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id); 1275 -- Reject completion of an incomplete or private type declarations 1276 -- having a known discriminant part by an unchecked union. 1277 1278 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id); 1279 -- Given the package entity of a generic package instantiation or 1280 -- formal package whose corresponding generic is a child unit, installs 1281 -- the private declarations of each of the child unit's parents. 1282 -- This has to be done at the point of entering the instance package's 1283 -- private part rather than being done in Sem_Ch12.Install_Parent 1284 -- (which is where the parents' visible declarations are installed). 1285 1286 ------------------------------------------------ 1287 -- Check_One_Tagged_Type_Or_Extension_At_Most -- 1288 ------------------------------------------------ 1289 1290 procedure Check_One_Tagged_Type_Or_Extension_At_Most is 1291 Previous : Node_Id; 1292 1293 procedure Check_Decls (Decls : List_Id); 1294 -- Check that either Previous is Empty and Decls does not contain 1295 -- more than one tagged type or type extension, or Previous is 1296 -- already set and Decls contains no tagged type or type extension. 1297 1298 ----------------- 1299 -- Check_Decls -- 1300 ----------------- 1301 1302 procedure Check_Decls (Decls : List_Id) is 1303 Decl : Node_Id; 1304 1305 begin 1306 Decl := First (Decls); 1307 while Present (Decl) loop 1308 if Nkind (Decl) = N_Full_Type_Declaration 1309 and then Is_Tagged_Type (Defining_Identifier (Decl)) 1310 then 1311 if No (Previous) then 1312 Previous := Decl; 1313 1314 else 1315 Error_Msg_Sloc := Sloc (Previous); 1316 Check_SPARK_05_Restriction 1317 ("at most one tagged type or type extension allowed", 1318 "\\ previous declaration#", 1319 Decl); 1320 end if; 1321 end if; 1322 1323 Next (Decl); 1324 end loop; 1325 end Check_Decls; 1326 1327 -- Start of processing for Check_One_Tagged_Type_Or_Extension_At_Most 1328 1329 begin 1330 Previous := Empty; 1331 Check_Decls (Vis_Decls); 1332 1333 if Present (Priv_Decls) then 1334 Check_Decls (Priv_Decls); 1335 end if; 1336 end Check_One_Tagged_Type_Or_Extension_At_Most; 1337 1338 --------------------- 1339 -- Clear_Constants -- 1340 --------------------- 1341 1342 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is 1343 E : Entity_Id; 1344 1345 begin 1346 -- Ignore package renamings, not interesting and they can cause self 1347 -- referential loops in the code below. 1348 1349 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then 1350 return; 1351 end if; 1352 1353 -- Note: in the loop below, the check for Next_Entity pointing back 1354 -- to the package entity may seem odd, but it is needed, because a 1355 -- package can contain a renaming declaration to itself, and such 1356 -- renamings are generated automatically within package instances. 1357 1358 E := FE; 1359 while Present (E) and then E /= Id loop 1360 if Is_Assignable (E) then 1361 Set_Never_Set_In_Source (E, False); 1362 Set_Is_True_Constant (E, False); 1363 Set_Current_Value (E, Empty); 1364 Set_Is_Known_Null (E, False); 1365 Set_Last_Assignment (E, Empty); 1366 1367 if not Can_Never_Be_Null (E) then 1368 Set_Is_Known_Non_Null (E, False); 1369 end if; 1370 1371 elsif Is_Package_Or_Generic_Package (E) then 1372 Clear_Constants (E, First_Entity (E)); 1373 Clear_Constants (E, First_Private_Entity (E)); 1374 end if; 1375 1376 Next_Entity (E); 1377 end loop; 1378 end Clear_Constants; 1379 1380 -------------------------------- 1381 -- Generate_Parent_References -- 1382 -------------------------------- 1383 1384 procedure Generate_Parent_References is 1385 Decl : constant Node_Id := Parent (N); 1386 1387 begin 1388 if Id = Cunit_Entity (Main_Unit) 1389 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit)) 1390 then 1391 Generate_Reference (Id, Scope (Id), 'k', False); 1392 1393 elsif not Nkind_In (Unit (Cunit (Main_Unit)), N_Subprogram_Body, 1394 N_Subunit) 1395 then 1396 -- If current unit is an ancestor of main unit, generate a 1397 -- reference to its own parent. 1398 1399 declare 1400 U : Node_Id; 1401 Main_Spec : Node_Id := Unit (Cunit (Main_Unit)); 1402 1403 begin 1404 if Nkind (Main_Spec) = N_Package_Body then 1405 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit))); 1406 end if; 1407 1408 U := Parent_Spec (Main_Spec); 1409 while Present (U) loop 1410 if U = Parent (Decl) then 1411 Generate_Reference (Id, Scope (Id), 'k', False); 1412 exit; 1413 1414 elsif Nkind (Unit (U)) = N_Package_Body then 1415 exit; 1416 1417 else 1418 U := Parent_Spec (Unit (U)); 1419 end if; 1420 end loop; 1421 end; 1422 end if; 1423 end Generate_Parent_References; 1424 1425 --------------------- 1426 -- Is_Public_Child -- 1427 --------------------- 1428 1429 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is 1430 begin 1431 if not Is_Private_Descendant (Child) then 1432 return True; 1433 else 1434 if Child = Unit then 1435 return not Private_Present ( 1436 Parent (Unit_Declaration_Node (Child))); 1437 else 1438 return Is_Public_Child (Scope (Child), Unit); 1439 end if; 1440 end if; 1441 end Is_Public_Child; 1442 1443 ---------------------------------------- 1444 -- Inspect_Unchecked_Union_Completion -- 1445 ---------------------------------------- 1446 1447 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is 1448 Decl : Node_Id; 1449 1450 begin 1451 Decl := First (Decls); 1452 while Present (Decl) loop 1453 1454 -- We are looking at an incomplete or private type declaration 1455 -- with a known_discriminant_part whose full view is an 1456 -- Unchecked_Union. The seemingly useless check with Is_Type 1457 -- prevents cascaded errors when routines defined only for type 1458 -- entities are called with non-type entities. 1459 1460 if Nkind_In (Decl, N_Incomplete_Type_Declaration, 1461 N_Private_Type_Declaration) 1462 and then Is_Type (Defining_Identifier (Decl)) 1463 and then Has_Discriminants (Defining_Identifier (Decl)) 1464 and then Present (Full_View (Defining_Identifier (Decl))) 1465 and then 1466 Is_Unchecked_Union (Full_View (Defining_Identifier (Decl))) 1467 then 1468 Error_Msg_N 1469 ("completion of discriminated partial view " 1470 & "cannot be an unchecked union", 1471 Full_View (Defining_Identifier (Decl))); 1472 end if; 1473 1474 Next (Decl); 1475 end loop; 1476 end Inspect_Unchecked_Union_Completion; 1477 1478 ----------------------------------------- 1479 -- Install_Parent_Private_Declarations -- 1480 ----------------------------------------- 1481 1482 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is 1483 Inst_Par : Entity_Id; 1484 Gen_Par : Entity_Id; 1485 Inst_Node : Node_Id; 1486 1487 begin 1488 Inst_Par := Inst_Id; 1489 1490 Gen_Par := 1491 Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par))); 1492 while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop 1493 Inst_Node := Get_Unit_Instantiation_Node (Inst_Par); 1494 1495 if Nkind_In (Inst_Node, N_Package_Instantiation, 1496 N_Formal_Package_Declaration) 1497 and then Nkind (Name (Inst_Node)) = N_Expanded_Name 1498 then 1499 Inst_Par := Entity (Prefix (Name (Inst_Node))); 1500 1501 if Present (Renamed_Entity (Inst_Par)) then 1502 Inst_Par := Renamed_Entity (Inst_Par); 1503 end if; 1504 1505 Gen_Par := 1506 Generic_Parent 1507 (Specification (Unit_Declaration_Node (Inst_Par))); 1508 1509 -- Install the private declarations and private use clauses 1510 -- of a parent instance of the child instance, unless the 1511 -- parent instance private declarations have already been 1512 -- installed earlier in Analyze_Package_Specification, which 1513 -- happens when a generic child is instantiated, and the 1514 -- instance is a child of the parent instance. 1515 1516 -- Installing the use clauses of the parent instance twice 1517 -- is both unnecessary and wrong, because it would cause the 1518 -- clauses to be chained to themselves in the use clauses 1519 -- list of the scope stack entry. That in turn would cause 1520 -- an endless loop from End_Use_Clauses upon scope exit. 1521 1522 -- The parent is now fully visible. It may be a hidden open 1523 -- scope if we are currently compiling some child instance 1524 -- declared within it, but while the current instance is being 1525 -- compiled the parent is immediately visible. In particular 1526 -- its entities must remain visible if a stack save/restore 1527 -- takes place through a call to Rtsfind. 1528 1529 if Present (Gen_Par) then 1530 if not In_Private_Part (Inst_Par) then 1531 Install_Private_Declarations (Inst_Par); 1532 Set_Use (Private_Declarations 1533 (Specification 1534 (Unit_Declaration_Node (Inst_Par)))); 1535 Set_Is_Hidden_Open_Scope (Inst_Par, False); 1536 end if; 1537 1538 -- If we've reached the end of the generic instance parents, 1539 -- then finish off by looping through the nongeneric parents 1540 -- and installing their private declarations. 1541 1542 -- If one of the non-generic parents is itself on the scope 1543 -- stack, do not install its private declarations: they are 1544 -- installed in due time when the private part of that parent 1545 -- is analyzed. 1546 1547 else 1548 while Present (Inst_Par) 1549 and then Inst_Par /= Standard_Standard 1550 and then (not In_Open_Scopes (Inst_Par) 1551 or else not In_Private_Part (Inst_Par)) 1552 loop 1553 if Nkind (Inst_Node) = N_Formal_Package_Declaration 1554 or else 1555 not Is_Ancestor_Package 1556 (Inst_Par, Cunit_Entity (Current_Sem_Unit)) 1557 then 1558 Install_Private_Declarations (Inst_Par); 1559 Set_Use 1560 (Private_Declarations 1561 (Specification 1562 (Unit_Declaration_Node (Inst_Par)))); 1563 Inst_Par := Scope (Inst_Par); 1564 else 1565 exit; 1566 end if; 1567 end loop; 1568 1569 exit; 1570 end if; 1571 1572 else 1573 exit; 1574 end if; 1575 end loop; 1576 end Install_Parent_Private_Declarations; 1577 1578 -- Start of processing for Analyze_Package_Specification 1579 1580 begin 1581 if Present (Vis_Decls) then 1582 Analyze_Declarations (Vis_Decls); 1583 end if; 1584 1585 -- Inspect the entities defined in the package and ensure that all 1586 -- incomplete types have received full declarations. Build default 1587 -- initial condition and invariant procedures for all qualifying types. 1588 1589 E := First_Entity (Id); 1590 while Present (E) loop 1591 1592 -- Check on incomplete types 1593 1594 -- AI05-0213: A formal incomplete type has no completion, and neither 1595 -- does the corresponding subtype in an instance. 1596 1597 if Is_Incomplete_Type (E) 1598 and then No (Full_View (E)) 1599 and then not Is_Generic_Type (E) 1600 and then not From_Limited_With (E) 1601 and then not Is_Generic_Actual_Type (E) 1602 then 1603 Error_Msg_N ("no declaration in visible part for incomplete}", E); 1604 end if; 1605 1606 Next_Entity (E); 1607 end loop; 1608 1609 if Is_Remote_Call_Interface (Id) 1610 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit 1611 then 1612 Validate_RCI_Declarations (Id); 1613 end if; 1614 1615 -- Save global references in the visible declarations, before installing 1616 -- private declarations of parent unit if there is one, because the 1617 -- privacy status of types defined in the parent will change. This is 1618 -- only relevant for generic child units, but is done in all cases for 1619 -- uniformity. 1620 1621 if Ekind (Id) = E_Generic_Package 1622 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration 1623 then 1624 declare 1625 Orig_Spec : constant Node_Id := Specification (Orig_Decl); 1626 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec); 1627 1628 begin 1629 -- Insert the freezing nodes after the visible declarations to 1630 -- ensure that we analyze its aspects; needed to ensure that 1631 -- global entities referenced in the aspects are properly handled. 1632 1633 if Ada_Version >= Ada_2012 1634 and then Is_Non_Empty_List (Vis_Decls) 1635 and then Is_Empty_List (Priv_Decls) 1636 then 1637 Insert_List_After_And_Analyze 1638 (Last (Vis_Decls), Freeze_Entity (Id, Last (Vis_Decls))); 1639 end if; 1640 1641 Set_Private_Declarations (Orig_Spec, Empty_List); 1642 Save_Global_References (Orig_Decl); 1643 Set_Private_Declarations (Orig_Spec, Save_Priv); 1644 end; 1645 end if; 1646 1647 -- If package is a public child unit, then make the private declarations 1648 -- of the parent visible. 1649 1650 Public_Child := False; 1651 1652 declare 1653 Par : Entity_Id; 1654 Pack_Decl : Node_Id; 1655 Par_Spec : Node_Id; 1656 1657 begin 1658 Par := Id; 1659 Par_Spec := Parent_Spec (Parent (N)); 1660 1661 -- If the package is formal package of an enclosing generic, it is 1662 -- transformed into a local generic declaration, and compiled to make 1663 -- its spec available. We need to retrieve the original generic to 1664 -- determine whether it is a child unit, and install its parents. 1665 1666 if No (Par_Spec) 1667 and then 1668 Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration 1669 then 1670 Par := Entity (Name (Original_Node (Parent (N)))); 1671 Par_Spec := Parent_Spec (Unit_Declaration_Node (Par)); 1672 end if; 1673 1674 if Present (Par_Spec) then 1675 Generate_Parent_References; 1676 1677 while Scope (Par) /= Standard_Standard 1678 and then Is_Public_Child (Id, Par) 1679 and then In_Open_Scopes (Par) 1680 loop 1681 Public_Child := True; 1682 Par := Scope (Par); 1683 Install_Private_Declarations (Par); 1684 Install_Private_With_Clauses (Par); 1685 Pack_Decl := Unit_Declaration_Node (Par); 1686 Set_Use (Private_Declarations (Specification (Pack_Decl))); 1687 end loop; 1688 end if; 1689 end; 1690 1691 if Is_Compilation_Unit (Id) then 1692 Install_Private_With_Clauses (Id); 1693 else 1694 -- The current compilation unit may include private with_clauses, 1695 -- which are visible in the private part of the current nested 1696 -- package, and have to be installed now. This is not done for 1697 -- nested instantiations, where the private with_clauses of the 1698 -- enclosing unit have no effect once the instantiation info is 1699 -- established and we start analyzing the package declaration. 1700 1701 declare 1702 Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit); 1703 begin 1704 if Is_Package_Or_Generic_Package (Comp_Unit) 1705 and then not In_Private_Part (Comp_Unit) 1706 and then not In_Instance 1707 then 1708 Install_Private_With_Clauses (Comp_Unit); 1709 Private_With_Clauses_Installed := True; 1710 end if; 1711 end; 1712 end if; 1713 1714 -- If this is a package associated with a generic instance or formal 1715 -- package, then the private declarations of each of the generic's 1716 -- parents must be installed at this point. 1717 1718 if Is_Generic_Instance (Id) then 1719 Install_Parent_Private_Declarations (Id); 1720 end if; 1721 1722 -- Analyze private part if present. The flag In_Private_Part is reset 1723 -- in End_Package_Scope. 1724 1725 L := Last_Entity (Id); 1726 1727 if Present (Priv_Decls) then 1728 Set_In_Private_Part (Id); 1729 1730 -- Upon entering a public child's private part, it may be necessary 1731 -- to declare subprograms that were derived in the package's visible 1732 -- part but not yet made visible. 1733 1734 if Public_Child then 1735 Declare_Inherited_Private_Subprograms (Id); 1736 end if; 1737 1738 Analyze_Declarations (Priv_Decls); 1739 1740 -- Check the private declarations for incomplete deferred constants 1741 1742 Inspect_Deferred_Constant_Completion (Priv_Decls); 1743 1744 -- The first private entity is the immediate follower of the last 1745 -- visible entity, if there was one. 1746 1747 if Present (L) then 1748 Set_First_Private_Entity (Id, Next_Entity (L)); 1749 else 1750 Set_First_Private_Entity (Id, First_Entity (Id)); 1751 end if; 1752 1753 -- There may be inherited private subprograms that need to be declared, 1754 -- even in the absence of an explicit private part. If there are any 1755 -- public declarations in the package and the package is a public child 1756 -- unit, then an implicit private part is assumed. 1757 1758 elsif Present (L) and then Public_Child then 1759 Set_In_Private_Part (Id); 1760 Declare_Inherited_Private_Subprograms (Id); 1761 Set_First_Private_Entity (Id, Next_Entity (L)); 1762 end if; 1763 1764 E := First_Entity (Id); 1765 while Present (E) loop 1766 1767 -- Check rule of 3.6(11), which in general requires waiting till all 1768 -- full types have been seen. 1769 1770 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then 1771 Check_Aliased_Component_Types (E); 1772 end if; 1773 1774 -- Check preelaborable initialization for full type completing a 1775 -- private type for which pragma Preelaborable_Initialization given. 1776 1777 if Is_Type (E) 1778 and then Must_Have_Preelab_Init (E) 1779 and then not Has_Preelaborable_Initialization (E) 1780 then 1781 Error_Msg_N 1782 ("full view of & does not have preelaborable initialization", E); 1783 end if; 1784 1785 Next_Entity (E); 1786 end loop; 1787 1788 -- Ada 2005 (AI-216): The completion of an incomplete or private type 1789 -- declaration having a known_discriminant_part shall not be an 1790 -- unchecked union type. 1791 1792 if Present (Vis_Decls) then 1793 Inspect_Unchecked_Union_Completion (Vis_Decls); 1794 end if; 1795 1796 if Present (Priv_Decls) then 1797 Inspect_Unchecked_Union_Completion (Priv_Decls); 1798 end if; 1799 1800 if Ekind (Id) = E_Generic_Package 1801 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration 1802 and then Present (Priv_Decls) 1803 then 1804 -- Save global references in private declarations, ignoring the 1805 -- visible declarations that were processed earlier. 1806 1807 declare 1808 Orig_Spec : constant Node_Id := Specification (Orig_Decl); 1809 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec); 1810 Save_Form : constant List_Id := 1811 Generic_Formal_Declarations (Orig_Decl); 1812 1813 begin 1814 -- Insert the freezing nodes after the private declarations to 1815 -- ensure that we analyze its aspects; needed to ensure that 1816 -- global entities referenced in the aspects are properly handled. 1817 1818 if Ada_Version >= Ada_2012 1819 and then Is_Non_Empty_List (Priv_Decls) 1820 then 1821 Insert_List_After_And_Analyze 1822 (Last (Priv_Decls), Freeze_Entity (Id, Last (Priv_Decls))); 1823 end if; 1824 1825 Set_Visible_Declarations (Orig_Spec, Empty_List); 1826 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List); 1827 Save_Global_References (Orig_Decl); 1828 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form); 1829 Set_Visible_Declarations (Orig_Spec, Save_Vis); 1830 end; 1831 end if; 1832 1833 Process_End_Label (N, 'e', Id); 1834 1835 -- Remove private_with_clauses of enclosing compilation unit, if they 1836 -- were installed. 1837 1838 if Private_With_Clauses_Installed then 1839 Remove_Private_With_Clauses (Cunit (Current_Sem_Unit)); 1840 end if; 1841 1842 -- For the case of a library level package, we must go through all the 1843 -- entities clearing the indications that the value may be constant and 1844 -- not modified. Why? Because any client of this package may modify 1845 -- these values freely from anywhere. This also applies to any nested 1846 -- packages or generic packages. 1847 1848 -- For now we unconditionally clear constants for packages that are 1849 -- instances of generic packages. The reason is that we do not have the 1850 -- body yet, and we otherwise think things are unreferenced when they 1851 -- are not. This should be fixed sometime (the effect is not terrible, 1852 -- we just lose some warnings, and also some cases of value propagation) 1853 -- ??? 1854 1855 if Is_Library_Level_Entity (Id) 1856 or else Is_Generic_Instance (Id) 1857 then 1858 Clear_Constants (Id, First_Entity (Id)); 1859 Clear_Constants (Id, First_Private_Entity (Id)); 1860 end if; 1861 1862 -- Issue an error in SPARK mode if a package specification contains 1863 -- more than one tagged type or type extension. 1864 1865 Check_One_Tagged_Type_Or_Extension_At_Most; 1866 1867 -- Output relevant information as to why the package requires a body. 1868 -- Do not consider generated packages as this exposes internal symbols 1869 -- and leads to confusing messages. 1870 1871 if List_Body_Required_Info 1872 and then In_Extended_Main_Source_Unit (Id) 1873 and then Unit_Requires_Body (Id) 1874 and then Comes_From_Source (Id) 1875 then 1876 Unit_Requires_Body_Info (Id); 1877 end if; 1878 1879 -- Nested package specs that do not require bodies are not checked for 1880 -- ineffective use clauses due to the possbility of subunits. This is 1881 -- because at this stage it is impossible to tell whether there will be 1882 -- a separate body. 1883 1884 if not Unit_Requires_Body (Id) 1885 and then Is_Compilation_Unit (Id) 1886 and then not Is_Private_Descendant (Id) 1887 then 1888 Update_Use_Clause_Chain; 1889 end if; 1890 end Analyze_Package_Specification; 1891 1892 -------------------------------------- 1893 -- Analyze_Private_Type_Declaration -- 1894 -------------------------------------- 1895 1896 procedure Analyze_Private_Type_Declaration (N : Node_Id) is 1897 Id : constant Entity_Id := Defining_Identifier (N); 1898 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity); 1899 1900 begin 1901 Generate_Definition (Id); 1902 Set_Is_Pure (Id, PF); 1903 Init_Size_Align (Id); 1904 1905 if not Is_Package_Or_Generic_Package (Current_Scope) 1906 or else In_Private_Part (Current_Scope) 1907 then 1908 Error_Msg_N ("invalid context for private declaration", N); 1909 end if; 1910 1911 New_Private_Type (N, Id, N); 1912 Set_Depends_On_Private (Id); 1913 1914 -- Set the SPARK mode from the current context 1915 1916 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma); 1917 Set_SPARK_Pragma_Inherited (Id); 1918 1919 if Has_Aspects (N) then 1920 Analyze_Aspect_Specifications (N, Id); 1921 end if; 1922 end Analyze_Private_Type_Declaration; 1923 1924 ---------------------------------- 1925 -- Check_Anonymous_Access_Types -- 1926 ---------------------------------- 1927 1928 procedure Check_Anonymous_Access_Types 1929 (Spec_Id : Entity_Id; 1930 P_Body : Node_Id) 1931 is 1932 E : Entity_Id; 1933 IR : Node_Id; 1934 1935 begin 1936 -- Itype references are only needed by gigi, to force elaboration of 1937 -- itypes. In the absence of code generation, they are not needed. 1938 1939 if not Expander_Active then 1940 return; 1941 end if; 1942 1943 E := First_Entity (Spec_Id); 1944 while Present (E) loop 1945 if Ekind (E) = E_Anonymous_Access_Type 1946 and then From_Limited_With (E) 1947 then 1948 IR := Make_Itype_Reference (Sloc (P_Body)); 1949 Set_Itype (IR, E); 1950 1951 if No (Declarations (P_Body)) then 1952 Set_Declarations (P_Body, New_List (IR)); 1953 else 1954 Prepend (IR, Declarations (P_Body)); 1955 end if; 1956 end if; 1957 1958 Next_Entity (E); 1959 end loop; 1960 end Check_Anonymous_Access_Types; 1961 1962 ------------------------------------------- 1963 -- Declare_Inherited_Private_Subprograms -- 1964 ------------------------------------------- 1965 1966 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is 1967 1968 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean; 1969 -- Check whether an inherited subprogram S is an operation of an 1970 -- untagged derived type T. 1971 1972 --------------------- 1973 -- Is_Primitive_Of -- 1974 --------------------- 1975 1976 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is 1977 Formal : Entity_Id; 1978 1979 begin 1980 -- If the full view is a scalar type, the type is the anonymous base 1981 -- type, but the operation mentions the first subtype, so check the 1982 -- signature against the base type. 1983 1984 if Base_Type (Etype (S)) = Base_Type (T) then 1985 return True; 1986 1987 else 1988 Formal := First_Formal (S); 1989 while Present (Formal) loop 1990 if Base_Type (Etype (Formal)) = Base_Type (T) then 1991 return True; 1992 end if; 1993 1994 Next_Formal (Formal); 1995 end loop; 1996 1997 return False; 1998 end if; 1999 end Is_Primitive_Of; 2000 2001 -- Local variables 2002 2003 E : Entity_Id; 2004 Op_List : Elist_Id; 2005 Op_Elmt : Elmt_Id; 2006 Op_Elmt_2 : Elmt_Id; 2007 Prim_Op : Entity_Id; 2008 New_Op : Entity_Id := Empty; 2009 Parent_Subp : Entity_Id; 2010 Tag : Entity_Id; 2011 2012 -- Start of processing for Declare_Inherited_Private_Subprograms 2013 2014 begin 2015 E := First_Entity (Id); 2016 while Present (E) loop 2017 2018 -- If the entity is a nonprivate type extension whose parent type 2019 -- is declared in an open scope, then the type may have inherited 2020 -- operations that now need to be made visible. Ditto if the entity 2021 -- is a formal derived type in a child unit. 2022 2023 if ((Is_Derived_Type (E) and then not Is_Private_Type (E)) 2024 or else 2025 (Nkind (Parent (E)) = N_Private_Extension_Declaration 2026 and then Is_Generic_Type (E))) 2027 and then In_Open_Scopes (Scope (Etype (E))) 2028 and then Is_Base_Type (E) 2029 then 2030 if Is_Tagged_Type (E) then 2031 Op_List := Primitive_Operations (E); 2032 New_Op := Empty; 2033 Tag := First_Tag_Component (E); 2034 2035 Op_Elmt := First_Elmt (Op_List); 2036 while Present (Op_Elmt) loop 2037 Prim_Op := Node (Op_Elmt); 2038 2039 -- Search primitives that are implicit operations with an 2040 -- internal name whose parent operation has a normal name. 2041 2042 if Present (Alias (Prim_Op)) 2043 and then Find_Dispatching_Type (Alias (Prim_Op)) /= E 2044 and then not Comes_From_Source (Prim_Op) 2045 and then Is_Internal_Name (Chars (Prim_Op)) 2046 and then not Is_Internal_Name (Chars (Alias (Prim_Op))) 2047 then 2048 Parent_Subp := Alias (Prim_Op); 2049 2050 -- Case 1: Check if the type has also an explicit 2051 -- overriding for this primitive. 2052 2053 Op_Elmt_2 := Next_Elmt (Op_Elmt); 2054 while Present (Op_Elmt_2) loop 2055 2056 -- Skip entities with attribute Interface_Alias since 2057 -- they are not overriding primitives (these entities 2058 -- link an interface primitive with their covering 2059 -- primitive) 2060 2061 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp) 2062 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2)) 2063 and then No (Interface_Alias (Node (Op_Elmt_2))) 2064 then 2065 -- The private inherited operation has been 2066 -- overridden by an explicit subprogram: 2067 -- replace the former by the latter. 2068 2069 New_Op := Node (Op_Elmt_2); 2070 Replace_Elmt (Op_Elmt, New_Op); 2071 Remove_Elmt (Op_List, Op_Elmt_2); 2072 Set_Overridden_Operation (New_Op, Parent_Subp); 2073 2074 -- We don't need to inherit its dispatching slot. 2075 -- Set_All_DT_Position has previously ensured that 2076 -- the same slot was assigned to the two primitives 2077 2078 if Present (Tag) 2079 and then Present (DTC_Entity (New_Op)) 2080 and then Present (DTC_Entity (Prim_Op)) 2081 then 2082 pragma Assert 2083 (DT_Position (New_Op) = DT_Position (Prim_Op)); 2084 null; 2085 end if; 2086 2087 goto Next_Primitive; 2088 end if; 2089 2090 Next_Elmt (Op_Elmt_2); 2091 end loop; 2092 2093 -- Case 2: We have not found any explicit overriding and 2094 -- hence we need to declare the operation (i.e., make it 2095 -- visible). 2096 2097 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E)); 2098 2099 -- Inherit the dispatching slot if E is already frozen 2100 2101 if Is_Frozen (E) 2102 and then Present (DTC_Entity (Alias (Prim_Op))) 2103 then 2104 Set_DTC_Entity_Value (E, New_Op); 2105 Set_DT_Position_Value (New_Op, 2106 DT_Position (Alias (Prim_Op))); 2107 end if; 2108 2109 pragma Assert 2110 (Is_Dispatching_Operation (New_Op) 2111 and then Node (Last_Elmt (Op_List)) = New_Op); 2112 2113 -- Substitute the new operation for the old one in the 2114 -- type's primitive operations list. Since the new 2115 -- operation was also just added to the end of list, 2116 -- the last element must be removed. 2117 2118 -- (Question: is there a simpler way of declaring the 2119 -- operation, say by just replacing the name of the 2120 -- earlier operation, reentering it in the in the symbol 2121 -- table (how?), and marking it as private???) 2122 2123 Replace_Elmt (Op_Elmt, New_Op); 2124 Remove_Last_Elmt (Op_List); 2125 end if; 2126 2127 <<Next_Primitive>> 2128 Next_Elmt (Op_Elmt); 2129 end loop; 2130 2131 -- Generate listing showing the contents of the dispatch table 2132 2133 if Debug_Flag_ZZ then 2134 Write_DT (E); 2135 end if; 2136 2137 else 2138 -- For untagged type, scan forward to locate inherited hidden 2139 -- operations. 2140 2141 Prim_Op := Next_Entity (E); 2142 while Present (Prim_Op) loop 2143 if Is_Subprogram (Prim_Op) 2144 and then Present (Alias (Prim_Op)) 2145 and then not Comes_From_Source (Prim_Op) 2146 and then Is_Internal_Name (Chars (Prim_Op)) 2147 and then not Is_Internal_Name (Chars (Alias (Prim_Op))) 2148 and then Is_Primitive_Of (E, Prim_Op) 2149 then 2150 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E)); 2151 end if; 2152 2153 Next_Entity (Prim_Op); 2154 2155 -- Derived operations appear immediately after the type 2156 -- declaration (or the following subtype indication for 2157 -- a derived scalar type). Further declarations cannot 2158 -- include inherited operations of the type. 2159 2160 if Present (Prim_Op) then 2161 exit when Ekind (Prim_Op) not in Overloadable_Kind; 2162 end if; 2163 end loop; 2164 end if; 2165 end if; 2166 2167 Next_Entity (E); 2168 end loop; 2169 end Declare_Inherited_Private_Subprograms; 2170 2171 ----------------------- 2172 -- End_Package_Scope -- 2173 ----------------------- 2174 2175 procedure End_Package_Scope (P : Entity_Id) is 2176 begin 2177 Uninstall_Declarations (P); 2178 Pop_Scope; 2179 end End_Package_Scope; 2180 2181 --------------------------- 2182 -- Exchange_Declarations -- 2183 --------------------------- 2184 2185 procedure Exchange_Declarations (Id : Entity_Id) is 2186 Full_Id : constant Entity_Id := Full_View (Id); 2187 H1 : constant Entity_Id := Homonym (Id); 2188 Next1 : constant Entity_Id := Next_Entity (Id); 2189 H2 : Entity_Id; 2190 Next2 : Entity_Id; 2191 2192 begin 2193 -- If missing full declaration for type, nothing to exchange 2194 2195 if No (Full_Id) then 2196 return; 2197 end if; 2198 2199 -- Otherwise complete the exchange, and preserve semantic links 2200 2201 Next2 := Next_Entity (Full_Id); 2202 H2 := Homonym (Full_Id); 2203 2204 -- Reset full declaration pointer to reflect the switched entities and 2205 -- readjust the next entity chains. 2206 2207 Exchange_Entities (Id, Full_Id); 2208 2209 Link_Entities (Id, Next1); 2210 Set_Homonym (Id, H1); 2211 2212 Set_Full_View (Full_Id, Id); 2213 Link_Entities (Full_Id, Next2); 2214 Set_Homonym (Full_Id, H2); 2215 end Exchange_Declarations; 2216 2217 ---------------------------- 2218 -- Install_Package_Entity -- 2219 ---------------------------- 2220 2221 procedure Install_Package_Entity (Id : Entity_Id) is 2222 begin 2223 if not Is_Internal (Id) then 2224 if Debug_Flag_E then 2225 Write_Str ("Install: "); 2226 Write_Name (Chars (Id)); 2227 Write_Eol; 2228 end if; 2229 2230 if Is_Child_Unit (Id) then 2231 null; 2232 2233 -- Do not enter implicitly inherited non-overridden subprograms of 2234 -- a tagged type back into visibility if they have non-conformant 2235 -- homographs (Ada RM 8.3 12.3/2). 2236 2237 elsif Is_Hidden_Non_Overridden_Subpgm (Id) then 2238 null; 2239 2240 else 2241 Set_Is_Immediately_Visible (Id); 2242 end if; 2243 end if; 2244 end Install_Package_Entity; 2245 2246 ---------------------------------- 2247 -- Install_Private_Declarations -- 2248 ---------------------------------- 2249 2250 procedure Install_Private_Declarations (P : Entity_Id) is 2251 Id : Entity_Id; 2252 Full : Entity_Id; 2253 Priv_Deps : Elist_Id; 2254 2255 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id); 2256 -- When the full view of a private type is made available, we do the 2257 -- same for its private dependents under proper visibility conditions. 2258 -- When compiling a grand-chid unit this needs to be done recursively. 2259 2260 ----------------------------- 2261 -- Swap_Private_Dependents -- 2262 ----------------------------- 2263 2264 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is 2265 Deps : Elist_Id; 2266 Priv : Entity_Id; 2267 Priv_Elmt : Elmt_Id; 2268 Is_Priv : Boolean; 2269 2270 begin 2271 Priv_Elmt := First_Elmt (Priv_Deps); 2272 while Present (Priv_Elmt) loop 2273 Priv := Node (Priv_Elmt); 2274 2275 -- Before the exchange, verify that the presence of the Full_View 2276 -- field. This field will be empty if the entity has already been 2277 -- installed due to a previous call. 2278 2279 if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv) 2280 then 2281 if Is_Private_Type (Priv) then 2282 Deps := Private_Dependents (Priv); 2283 Is_Priv := True; 2284 else 2285 Is_Priv := False; 2286 end if; 2287 2288 -- For each subtype that is swapped, we also swap the reference 2289 -- to it in Private_Dependents, to allow access to it when we 2290 -- swap them out in End_Package_Scope. 2291 2292 Replace_Elmt (Priv_Elmt, Full_View (Priv)); 2293 2294 -- Ensure that both views of the dependent private subtype are 2295 -- immediately visible if within some open scope. Check full 2296 -- view before exchanging views. 2297 2298 if In_Open_Scopes (Scope (Full_View (Priv))) then 2299 Set_Is_Immediately_Visible (Priv); 2300 end if; 2301 2302 Exchange_Declarations (Priv); 2303 Set_Is_Immediately_Visible 2304 (Priv, In_Open_Scopes (Scope (Priv))); 2305 2306 Set_Is_Potentially_Use_Visible 2307 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt))); 2308 2309 -- Within a child unit, recurse, except in generic child unit, 2310 -- which (unfortunately) handle private_dependents separately. 2311 2312 if Is_Priv 2313 and then Is_Child_Unit (Cunit_Entity (Current_Sem_Unit)) 2314 and then not Is_Empty_Elmt_List (Deps) 2315 and then not Inside_A_Generic 2316 then 2317 Swap_Private_Dependents (Deps); 2318 end if; 2319 end if; 2320 2321 Next_Elmt (Priv_Elmt); 2322 end loop; 2323 end Swap_Private_Dependents; 2324 2325 -- Start of processing for Install_Private_Declarations 2326 2327 begin 2328 -- First exchange declarations for private types, so that the full 2329 -- declaration is visible. For each private type, we check its 2330 -- Private_Dependents list and also exchange any subtypes of or derived 2331 -- types from it. Finally, if this is a Taft amendment type, the 2332 -- incomplete declaration is irrelevant, and we want to link the 2333 -- eventual full declaration with the original private one so we 2334 -- also skip the exchange. 2335 2336 Id := First_Entity (P); 2337 while Present (Id) and then Id /= First_Private_Entity (P) loop 2338 if Is_Private_Base_Type (Id) 2339 and then Present (Full_View (Id)) 2340 and then Comes_From_Source (Full_View (Id)) 2341 and then Scope (Full_View (Id)) = Scope (Id) 2342 and then Ekind (Full_View (Id)) /= E_Incomplete_Type 2343 then 2344 -- If there is a use-type clause on the private type, set the full 2345 -- view accordingly. 2346 2347 Set_In_Use (Full_View (Id), In_Use (Id)); 2348 Full := Full_View (Id); 2349 2350 if Is_Private_Base_Type (Full) 2351 and then Has_Private_Declaration (Full) 2352 and then Nkind (Parent (Full)) = N_Full_Type_Declaration 2353 and then In_Open_Scopes (Scope (Etype (Full))) 2354 and then In_Package_Body (Current_Scope) 2355 and then not Is_Private_Type (Etype (Full)) 2356 then 2357 -- This is the completion of a private type by a derivation 2358 -- from another private type which is not private anymore. This 2359 -- can only happen in a package nested within a child package, 2360 -- when the parent type is defined in the parent unit. At this 2361 -- point the current type is not private either, and we have 2362 -- to install the underlying full view, which is now visible. 2363 -- Save the current full view as well, so that all views can be 2364 -- restored on exit. It may seem that after compiling the child 2365 -- body there are not environments to restore, but the back-end 2366 -- expects those links to be valid, and freeze nodes depend on 2367 -- them. 2368 2369 if No (Full_View (Full)) 2370 and then Present (Underlying_Full_View (Full)) 2371 then 2372 Set_Full_View (Id, Underlying_Full_View (Full)); 2373 Set_Underlying_Full_View (Id, Full); 2374 Set_Is_Underlying_Full_View (Full); 2375 2376 Set_Underlying_Full_View (Full, Empty); 2377 Set_Is_Frozen (Full_View (Id)); 2378 end if; 2379 end if; 2380 2381 Priv_Deps := Private_Dependents (Id); 2382 Exchange_Declarations (Id); 2383 Set_Is_Immediately_Visible (Id); 2384 Swap_Private_Dependents (Priv_Deps); 2385 end if; 2386 2387 Next_Entity (Id); 2388 end loop; 2389 2390 -- Next make other declarations in the private part visible as well 2391 2392 Id := First_Private_Entity (P); 2393 while Present (Id) loop 2394 Install_Package_Entity (Id); 2395 Set_Is_Hidden (Id, False); 2396 Next_Entity (Id); 2397 end loop; 2398 2399 -- An abstract state is partially refined when it has at least one 2400 -- Part_Of constituent. Since these constituents are being installed 2401 -- into visibility, update the partial refinement status of any state 2402 -- defined in the associated package, subject to at least one Part_Of 2403 -- constituent. 2404 2405 if Ekind_In (P, E_Generic_Package, E_Package) then 2406 declare 2407 States : constant Elist_Id := Abstract_States (P); 2408 State_Elmt : Elmt_Id; 2409 State_Id : Entity_Id; 2410 2411 begin 2412 if Present (States) then 2413 State_Elmt := First_Elmt (States); 2414 while Present (State_Elmt) loop 2415 State_Id := Node (State_Elmt); 2416 2417 if Present (Part_Of_Constituents (State_Id)) then 2418 Set_Has_Partial_Visible_Refinement (State_Id); 2419 end if; 2420 2421 Next_Elmt (State_Elmt); 2422 end loop; 2423 end if; 2424 end; 2425 end if; 2426 2427 -- Indicate that the private part is currently visible, so it can be 2428 -- properly reset on exit. 2429 2430 Set_In_Private_Part (P); 2431 end Install_Private_Declarations; 2432 2433 ---------------------------------- 2434 -- Install_Visible_Declarations -- 2435 ---------------------------------- 2436 2437 procedure Install_Visible_Declarations (P : Entity_Id) is 2438 Id : Entity_Id; 2439 Last_Entity : Entity_Id; 2440 2441 begin 2442 pragma Assert 2443 (Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P)); 2444 2445 if Is_Package_Or_Generic_Package (P) then 2446 Last_Entity := First_Private_Entity (P); 2447 else 2448 Last_Entity := Empty; 2449 end if; 2450 2451 Id := First_Entity (P); 2452 while Present (Id) and then Id /= Last_Entity loop 2453 Install_Package_Entity (Id); 2454 Next_Entity (Id); 2455 end loop; 2456 end Install_Visible_Declarations; 2457 2458 -------------------------- 2459 -- Is_Private_Base_Type -- 2460 -------------------------- 2461 2462 function Is_Private_Base_Type (E : Entity_Id) return Boolean is 2463 begin 2464 return Ekind (E) = E_Private_Type 2465 or else Ekind (E) = E_Limited_Private_Type 2466 or else Ekind (E) = E_Record_Type_With_Private; 2467 end Is_Private_Base_Type; 2468 2469 -------------------------- 2470 -- Is_Visible_Dependent -- 2471 -------------------------- 2472 2473 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean 2474 is 2475 S : constant Entity_Id := Scope (Dep); 2476 2477 begin 2478 -- Renamings created for actual types have the visibility of the actual 2479 2480 if Ekind (S) = E_Package 2481 and then Is_Generic_Instance (S) 2482 and then (Is_Generic_Actual_Type (Dep) 2483 or else Is_Generic_Actual_Type (Full_View (Dep))) 2484 then 2485 return True; 2486 2487 elsif not (Is_Derived_Type (Dep)) 2488 and then Is_Derived_Type (Full_View (Dep)) 2489 then 2490 -- When instantiating a package body, the scope stack is empty, so 2491 -- check instead whether the dependent type is defined in the same 2492 -- scope as the instance itself. 2493 2494 return In_Open_Scopes (S) 2495 or else (Is_Generic_Instance (Current_Scope) 2496 and then Scope (Dep) = Scope (Current_Scope)); 2497 else 2498 return True; 2499 end if; 2500 end Is_Visible_Dependent; 2501 2502 ---------------------------- 2503 -- May_Need_Implicit_Body -- 2504 ---------------------------- 2505 2506 procedure May_Need_Implicit_Body (E : Entity_Id) is 2507 P : constant Node_Id := Unit_Declaration_Node (E); 2508 S : constant Node_Id := Parent (P); 2509 B : Node_Id; 2510 Decls : List_Id; 2511 2512 begin 2513 if not Has_Completion (E) 2514 and then Nkind (P) = N_Package_Declaration 2515 and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E)) 2516 then 2517 B := 2518 Make_Package_Body (Sloc (E), 2519 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E), 2520 Chars => Chars (E)), 2521 Declarations => New_List); 2522 2523 if Nkind (S) = N_Package_Specification then 2524 if Present (Private_Declarations (S)) then 2525 Decls := Private_Declarations (S); 2526 else 2527 Decls := Visible_Declarations (S); 2528 end if; 2529 else 2530 Decls := Declarations (S); 2531 end if; 2532 2533 Append (B, Decls); 2534 Analyze (B); 2535 end if; 2536 end May_Need_Implicit_Body; 2537 2538 ---------------------- 2539 -- New_Private_Type -- 2540 ---------------------- 2541 2542 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is 2543 begin 2544 -- For other than Ada 2012, enter the name in the current scope 2545 2546 if Ada_Version < Ada_2012 then 2547 Enter_Name (Id); 2548 2549 -- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that 2550 -- there may be an incomplete previous view. 2551 2552 else 2553 declare 2554 Prev : Entity_Id; 2555 begin 2556 Prev := Find_Type_Name (N); 2557 pragma Assert (Prev = Id 2558 or else (Ekind (Prev) = E_Incomplete_Type 2559 and then Present (Full_View (Prev)) 2560 and then Full_View (Prev) = Id)); 2561 end; 2562 end if; 2563 2564 if Limited_Present (Def) then 2565 Set_Ekind (Id, E_Limited_Private_Type); 2566 else 2567 Set_Ekind (Id, E_Private_Type); 2568 end if; 2569 2570 Set_Etype (Id, Id); 2571 Set_Has_Delayed_Freeze (Id); 2572 Set_Is_First_Subtype (Id); 2573 Init_Size_Align (Id); 2574 2575 Set_Is_Constrained (Id, 2576 No (Discriminant_Specifications (N)) 2577 and then not Unknown_Discriminants_Present (N)); 2578 2579 -- Set tagged flag before processing discriminants, to catch illegal 2580 -- usage. 2581 2582 Set_Is_Tagged_Type (Id, Tagged_Present (Def)); 2583 2584 Set_Discriminant_Constraint (Id, No_Elist); 2585 Set_Stored_Constraint (Id, No_Elist); 2586 2587 if Present (Discriminant_Specifications (N)) then 2588 Push_Scope (Id); 2589 Process_Discriminants (N); 2590 End_Scope; 2591 2592 elsif Unknown_Discriminants_Present (N) then 2593 Set_Has_Unknown_Discriminants (Id); 2594 end if; 2595 2596 Set_Private_Dependents (Id, New_Elmt_List); 2597 2598 if Tagged_Present (Def) then 2599 Set_Ekind (Id, E_Record_Type_With_Private); 2600 Set_Direct_Primitive_Operations (Id, New_Elmt_List); 2601 Set_Is_Abstract_Type (Id, Abstract_Present (Def)); 2602 Set_Is_Limited_Record (Id, Limited_Present (Def)); 2603 Set_Has_Delayed_Freeze (Id, True); 2604 2605 -- Recognize Ada.Real_Time.Timing_Events.Timing_Events here 2606 2607 if Is_RTE (Id, RE_Timing_Event) then 2608 Set_Has_Timing_Event (Id); 2609 end if; 2610 2611 -- Create a class-wide type with the same attributes 2612 2613 Make_Class_Wide_Type (Id); 2614 2615 elsif Abstract_Present (Def) then 2616 Error_Msg_N ("only a tagged type can be abstract", N); 2617 end if; 2618 end New_Private_Type; 2619 2620 --------------------------------- 2621 -- Requires_Completion_In_Body -- 2622 --------------------------------- 2623 2624 function Requires_Completion_In_Body 2625 (Id : Entity_Id; 2626 Pack_Id : Entity_Id; 2627 Do_Abstract_States : Boolean := False) return Boolean 2628 is 2629 begin 2630 -- Always ignore child units. Child units get added to the entity list 2631 -- of a parent unit, but are not original entities of the parent, and 2632 -- so do not affect whether the parent needs a body. 2633 2634 if Is_Child_Unit (Id) then 2635 return False; 2636 2637 -- Ignore formal packages and their renamings 2638 2639 elsif Ekind (Id) = E_Package 2640 and then Nkind (Original_Node (Unit_Declaration_Node (Id))) = 2641 N_Formal_Package_Declaration 2642 then 2643 return False; 2644 2645 -- Otherwise test to see if entity requires a completion. Note that 2646 -- subprogram entities whose declaration does not come from source are 2647 -- ignored here on the basis that we assume the expander will provide an 2648 -- implicit completion at some point. 2649 2650 elsif (Is_Overloadable (Id) 2651 and then not Ekind_In (Id, E_Enumeration_Literal, E_Operator) 2652 and then not Is_Abstract_Subprogram (Id) 2653 and then not Has_Completion (Id) 2654 and then Comes_From_Source (Parent (Id))) 2655 2656 or else 2657 (Ekind (Id) = E_Package 2658 and then Id /= Pack_Id 2659 and then not Has_Completion (Id) 2660 and then Unit_Requires_Body (Id, Do_Abstract_States)) 2661 2662 or else 2663 (Ekind (Id) = E_Incomplete_Type 2664 and then No (Full_View (Id)) 2665 and then not Is_Generic_Type (Id)) 2666 2667 or else 2668 (Ekind_In (Id, E_Task_Type, E_Protected_Type) 2669 and then not Has_Completion (Id)) 2670 2671 or else 2672 (Ekind (Id) = E_Generic_Package 2673 and then Id /= Pack_Id 2674 and then not Has_Completion (Id) 2675 and then Unit_Requires_Body (Id, Do_Abstract_States)) 2676 2677 or else 2678 (Is_Generic_Subprogram (Id) 2679 and then not Has_Completion (Id)) 2680 then 2681 return True; 2682 2683 -- Otherwise the entity does not require completion in a package body 2684 2685 else 2686 return False; 2687 end if; 2688 end Requires_Completion_In_Body; 2689 2690 ---------------------------- 2691 -- Uninstall_Declarations -- 2692 ---------------------------- 2693 2694 procedure Uninstall_Declarations (P : Entity_Id) is 2695 Decl : constant Node_Id := Unit_Declaration_Node (P); 2696 Id : Entity_Id; 2697 Full : Entity_Id; 2698 Priv_Elmt : Elmt_Id; 2699 Priv_Sub : Entity_Id; 2700 2701 procedure Preserve_Full_Attributes (Priv : Entity_Id; Full : Entity_Id); 2702 -- Copy to the private declaration the attributes of the full view that 2703 -- need to be available for the partial view also. 2704 2705 function Type_In_Use (T : Entity_Id) return Boolean; 2706 -- Check whether type or base type appear in an active use_type clause 2707 2708 ------------------------------ 2709 -- Preserve_Full_Attributes -- 2710 ------------------------------ 2711 2712 procedure Preserve_Full_Attributes 2713 (Priv : Entity_Id; 2714 Full : Entity_Id) 2715 is 2716 Full_Base : constant Entity_Id := Base_Type (Full); 2717 Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv); 2718 2719 begin 2720 Set_Size_Info (Priv, Full); 2721 Set_RM_Size (Priv, RM_Size (Full)); 2722 Set_Size_Known_At_Compile_Time 2723 (Priv, Size_Known_At_Compile_Time (Full)); 2724 Set_Is_Volatile (Priv, Is_Volatile (Full)); 2725 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full)); 2726 Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full)); 2727 Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full)); 2728 Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full)); 2729 Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full)); 2730 Set_Has_Pragma_Unreferenced_Objects 2731 (Priv, Has_Pragma_Unreferenced_Objects 2732 (Full)); 2733 if Is_Unchecked_Union (Full) then 2734 Set_Is_Unchecked_Union (Base_Type (Priv)); 2735 end if; 2736 -- Why is atomic not copied here ??? 2737 2738 if Referenced (Full) then 2739 Set_Referenced (Priv); 2740 end if; 2741 2742 if Priv_Is_Base_Type then 2743 Set_Is_Controlled_Active 2744 (Priv, Is_Controlled_Active (Full_Base)); 2745 Set_Finalize_Storage_Only 2746 (Priv, Finalize_Storage_Only (Full_Base)); 2747 Set_Has_Controlled_Component 2748 (Priv, Has_Controlled_Component (Full_Base)); 2749 2750 Propagate_Concurrent_Flags (Priv, Base_Type (Full)); 2751 end if; 2752 2753 -- As explained in Freeze_Entity, private types are required to point 2754 -- to the same freeze node as their corresponding full view, if any. 2755 -- But we ought not to overwrite a node already inserted in the tree. 2756 2757 pragma Assert 2758 (Serious_Errors_Detected /= 0 2759 or else No (Freeze_Node (Priv)) 2760 or else No (Parent (Freeze_Node (Priv))) 2761 or else Freeze_Node (Priv) = Freeze_Node (Full)); 2762 2763 Set_Freeze_Node (Priv, Freeze_Node (Full)); 2764 2765 -- Propagate Default_Initial_Condition-related attributes from the 2766 -- base type of the full view to the full view and vice versa. This 2767 -- may seem strange, but is necessary depending on which type 2768 -- triggered the generation of the DIC procedure body. As a result, 2769 -- both the full view and its base type carry the same DIC-related 2770 -- information. 2771 2772 Propagate_DIC_Attributes (Full, From_Typ => Full_Base); 2773 Propagate_DIC_Attributes (Full_Base, From_Typ => Full); 2774 2775 -- Propagate Default_Initial_Condition-related attributes from the 2776 -- full view to the private view. 2777 2778 Propagate_DIC_Attributes (Priv, From_Typ => Full); 2779 2780 -- Propagate invariant-related attributes from the base type of the 2781 -- full view to the full view and vice versa. This may seem strange, 2782 -- but is necessary depending on which type triggered the generation 2783 -- of the invariant procedure body. As a result, both the full view 2784 -- and its base type carry the same invariant-related information. 2785 2786 Propagate_Invariant_Attributes (Full, From_Typ => Full_Base); 2787 Propagate_Invariant_Attributes (Full_Base, From_Typ => Full); 2788 2789 -- Propagate invariant-related attributes from the full view to the 2790 -- private view. 2791 2792 Propagate_Invariant_Attributes (Priv, From_Typ => Full); 2793 2794 if Is_Tagged_Type (Priv) 2795 and then Is_Tagged_Type (Full) 2796 and then not Error_Posted (Full) 2797 then 2798 if Is_Tagged_Type (Priv) then 2799 2800 -- If the type is tagged, the tag itself must be available on 2801 -- the partial view, for expansion purposes. 2802 2803 Set_First_Entity (Priv, First_Entity (Full)); 2804 2805 -- If there are discriminants in the partial view, these remain 2806 -- visible. Otherwise only the tag itself is visible, and there 2807 -- are no nameable components in the partial view. 2808 2809 if No (Last_Entity (Priv)) then 2810 Set_Last_Entity (Priv, First_Entity (Priv)); 2811 end if; 2812 end if; 2813 2814 Set_Has_Discriminants (Priv, Has_Discriminants (Full)); 2815 2816 if Has_Discriminants (Full) then 2817 Set_Discriminant_Constraint (Priv, 2818 Discriminant_Constraint (Full)); 2819 end if; 2820 end if; 2821 end Preserve_Full_Attributes; 2822 2823 ----------------- 2824 -- Type_In_Use -- 2825 ----------------- 2826 2827 function Type_In_Use (T : Entity_Id) return Boolean is 2828 begin 2829 return Scope (Base_Type (T)) = P 2830 and then (In_Use (T) or else In_Use (Base_Type (T))); 2831 end Type_In_Use; 2832 2833 -- Start of processing for Uninstall_Declarations 2834 2835 begin 2836 Id := First_Entity (P); 2837 while Present (Id) and then Id /= First_Private_Entity (P) loop 2838 if Debug_Flag_E then 2839 Write_Str ("unlinking visible entity "); 2840 Write_Int (Int (Id)); 2841 Write_Eol; 2842 end if; 2843 2844 -- On exit from the package scope, we must preserve the visibility 2845 -- established by use clauses in the current scope. Two cases: 2846 2847 -- a) If the entity is an operator, it may be a primitive operator of 2848 -- a type for which there is a visible use-type clause. 2849 2850 -- b) For other entities, their use-visibility is determined by a 2851 -- visible use clause for the package itself or a use-all-type clause 2852 -- applied directly to the entity's type. For a generic instance, 2853 -- the instantiation of the formals appears in the visible part, 2854 -- but the formals are private and remain so. 2855 2856 if Ekind (Id) = E_Function 2857 and then Is_Operator_Symbol_Name (Chars (Id)) 2858 and then not Is_Hidden (Id) 2859 and then not Error_Posted (Id) 2860 then 2861 Set_Is_Potentially_Use_Visible (Id, 2862 In_Use (P) 2863 or else Type_In_Use (Etype (Id)) 2864 or else Type_In_Use (Etype (First_Formal (Id))) 2865 or else (Present (Next_Formal (First_Formal (Id))) 2866 and then 2867 Type_In_Use 2868 (Etype (Next_Formal (First_Formal (Id)))))); 2869 else 2870 if In_Use (P) and then not Is_Hidden (Id) then 2871 2872 -- A child unit of a use-visible package remains use-visible 2873 -- only if it is itself a visible child unit. Otherwise it 2874 -- would remain visible in other contexts where P is use- 2875 -- visible, because once compiled it stays in the entity list 2876 -- of its parent unit. 2877 2878 if Is_Child_Unit (Id) then 2879 Set_Is_Potentially_Use_Visible 2880 (Id, Is_Visible_Lib_Unit (Id)); 2881 else 2882 Set_Is_Potentially_Use_Visible (Id); 2883 end if; 2884 2885 -- We need to avoid incorrectly marking enumeration literals as 2886 -- non-visible when a visible use-all-type clause is in effect. 2887 2888 elsif Type_In_Use (Etype (Id)) 2889 and then Nkind (Current_Use_Clause (Etype (Id))) = 2890 N_Use_Type_Clause 2891 and then All_Present (Current_Use_Clause (Etype (Id))) 2892 then 2893 null; 2894 2895 else 2896 Set_Is_Potentially_Use_Visible (Id, False); 2897 end if; 2898 end if; 2899 2900 -- Local entities are not immediately visible outside of the package 2901 2902 Set_Is_Immediately_Visible (Id, False); 2903 2904 -- If this is a private type with a full view (for example a local 2905 -- subtype of a private type declared elsewhere), ensure that the 2906 -- full view is also removed from visibility: it may be exposed when 2907 -- swapping views in an instantiation. Similarly, ensure that the 2908 -- use-visibility is properly set on both views. 2909 2910 if Is_Type (Id) and then Present (Full_View (Id)) then 2911 Set_Is_Immediately_Visible (Full_View (Id), False); 2912 Set_Is_Potentially_Use_Visible (Full_View (Id), 2913 Is_Potentially_Use_Visible (Id)); 2914 end if; 2915 2916 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then 2917 Check_Abstract_Overriding (Id); 2918 Check_Conventions (Id); 2919 end if; 2920 2921 if Ekind_In (Id, E_Private_Type, E_Limited_Private_Type) 2922 and then No (Full_View (Id)) 2923 and then not Is_Generic_Type (Id) 2924 and then not Is_Derived_Type (Id) 2925 then 2926 Error_Msg_N ("missing full declaration for private type&", Id); 2927 2928 elsif Ekind (Id) = E_Record_Type_With_Private 2929 and then not Is_Generic_Type (Id) 2930 and then No (Full_View (Id)) 2931 then 2932 if Nkind (Parent (Id)) = N_Private_Type_Declaration then 2933 Error_Msg_N ("missing full declaration for private type&", Id); 2934 else 2935 Error_Msg_N 2936 ("missing full declaration for private extension", Id); 2937 end if; 2938 2939 -- Case of constant, check for deferred constant declaration with 2940 -- no full view. Likely just a matter of a missing expression, or 2941 -- accidental use of the keyword constant. 2942 2943 elsif Ekind (Id) = E_Constant 2944 2945 -- OK if constant value present 2946 2947 and then No (Constant_Value (Id)) 2948 2949 -- OK if full view present 2950 2951 and then No (Full_View (Id)) 2952 2953 -- OK if imported, since that provides the completion 2954 2955 and then not Is_Imported (Id) 2956 2957 -- OK if object declaration replaced by renaming declaration as 2958 -- a result of OK_To_Rename processing (e.g. for concatenation) 2959 2960 and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration 2961 2962 -- OK if object declaration with the No_Initialization flag set 2963 2964 and then not (Nkind (Parent (Id)) = N_Object_Declaration 2965 and then No_Initialization (Parent (Id))) 2966 then 2967 -- If no private declaration is present, we assume the user did 2968 -- not intend a deferred constant declaration and the problem 2969 -- is simply that the initializing expression is missing. 2970 2971 if not Has_Private_Declaration (Etype (Id)) then 2972 2973 -- We assume that the user did not intend a deferred constant 2974 -- declaration, and the expression is just missing. 2975 2976 Error_Msg_N 2977 ("constant declaration requires initialization expression", 2978 Parent (Id)); 2979 2980 if Is_Limited_Type (Etype (Id)) then 2981 Error_Msg_N 2982 ("\if variable intended, remove CONSTANT from declaration", 2983 Parent (Id)); 2984 end if; 2985 2986 -- Otherwise if a private declaration is present, then we are 2987 -- missing the full declaration for the deferred constant. 2988 2989 else 2990 Error_Msg_N 2991 ("missing full declaration for deferred constant (RM 7.4)", 2992 Id); 2993 2994 if Is_Limited_Type (Etype (Id)) then 2995 Error_Msg_N 2996 ("\if variable intended, remove CONSTANT from declaration", 2997 Parent (Id)); 2998 end if; 2999 end if; 3000 end if; 3001 3002 Next_Entity (Id); 3003 end loop; 3004 3005 -- If the specification was installed as the parent of a public child 3006 -- unit, the private declarations were not installed, and there is 3007 -- nothing to do. 3008 3009 if not In_Private_Part (P) then 3010 return; 3011 else 3012 Set_In_Private_Part (P, False); 3013 end if; 3014 3015 -- Make private entities invisible and exchange full and private 3016 -- declarations for private types. Id is now the first private entity 3017 -- in the package. 3018 3019 while Present (Id) loop 3020 if Debug_Flag_E then 3021 Write_Str ("unlinking private entity "); 3022 Write_Int (Int (Id)); 3023 Write_Eol; 3024 end if; 3025 3026 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then 3027 Check_Abstract_Overriding (Id); 3028 Check_Conventions (Id); 3029 end if; 3030 3031 Set_Is_Immediately_Visible (Id, False); 3032 3033 if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then 3034 Full := Full_View (Id); 3035 3036 -- If the partial view is not declared in the visible part of the 3037 -- package (as is the case when it is a type derived from some 3038 -- other private type in the private part of the current package), 3039 -- no exchange takes place. 3040 3041 if No (Parent (Id)) 3042 or else List_Containing (Parent (Id)) /= 3043 Visible_Declarations (Specification (Decl)) 3044 then 3045 goto Next_Id; 3046 end if; 3047 3048 -- The entry in the private part points to the full declaration, 3049 -- which is currently visible. Exchange them so only the private 3050 -- type declaration remains accessible, and link private and full 3051 -- declaration in the opposite direction. Before the actual 3052 -- exchange, we copy back attributes of the full view that must 3053 -- be available to the partial view too. 3054 3055 Preserve_Full_Attributes (Id, Full); 3056 3057 Set_Is_Potentially_Use_Visible (Id, In_Use (P)); 3058 3059 -- The following test may be redundant, as this is already 3060 -- diagnosed in sem_ch3. ??? 3061 3062 if not Is_Definite_Subtype (Full) 3063 and then Is_Definite_Subtype (Id) 3064 then 3065 Error_Msg_Sloc := Sloc (Parent (Id)); 3066 Error_Msg_NE 3067 ("full view of& not compatible with declaration#", Full, Id); 3068 end if; 3069 3070 -- Swap out the subtypes and derived types of Id that 3071 -- were compiled in this scope, or installed previously 3072 -- by Install_Private_Declarations. 3073 3074 -- Before we do the swap, we verify the presence of the Full_View 3075 -- field which may be empty due to a swap by a previous call to 3076 -- End_Package_Scope (e.g. from the freezing mechanism). 3077 3078 Priv_Elmt := First_Elmt (Private_Dependents (Id)); 3079 while Present (Priv_Elmt) loop 3080 Priv_Sub := Node (Priv_Elmt); 3081 3082 if Present (Full_View (Priv_Sub)) then 3083 if Scope (Priv_Sub) = P 3084 or else not In_Open_Scopes (Scope (Priv_Sub)) 3085 then 3086 Set_Is_Immediately_Visible (Priv_Sub, False); 3087 end if; 3088 3089 if Is_Visible_Dependent (Priv_Sub) then 3090 Preserve_Full_Attributes 3091 (Priv_Sub, Full_View (Priv_Sub)); 3092 Replace_Elmt (Priv_Elmt, Full_View (Priv_Sub)); 3093 Exchange_Declarations (Priv_Sub); 3094 end if; 3095 end if; 3096 3097 Next_Elmt (Priv_Elmt); 3098 end loop; 3099 3100 -- Now restore the type itself to its private view 3101 3102 Exchange_Declarations (Id); 3103 3104 -- If we have installed an underlying full view for a type derived 3105 -- from a private type in a child unit, restore the proper views 3106 -- of private and full view. See corresponding code in 3107 -- Install_Private_Declarations. 3108 3109 -- After the exchange, Full denotes the private type in the 3110 -- visible part of the package. 3111 3112 if Is_Private_Base_Type (Full) 3113 and then Present (Full_View (Full)) 3114 and then Present (Underlying_Full_View (Full)) 3115 and then In_Package_Body (Current_Scope) 3116 then 3117 Set_Full_View (Full, Underlying_Full_View (Full)); 3118 Set_Underlying_Full_View (Full, Empty); 3119 end if; 3120 3121 elsif Ekind (Id) = E_Incomplete_Type 3122 and then Comes_From_Source (Id) 3123 and then No (Full_View (Id)) 3124 then 3125 -- Mark Taft amendment types. Verify that there are no primitive 3126 -- operations declared for the type (3.10.1(9)). 3127 3128 Set_Has_Completion_In_Body (Id); 3129 3130 declare 3131 Elmt : Elmt_Id; 3132 Subp : Entity_Id; 3133 3134 begin 3135 Elmt := First_Elmt (Private_Dependents (Id)); 3136 while Present (Elmt) loop 3137 Subp := Node (Elmt); 3138 3139 -- Is_Primitive is tested because there can be cases where 3140 -- nonprimitive subprograms (in nested packages) are added 3141 -- to the Private_Dependents list. 3142 3143 if Is_Overloadable (Subp) and then Is_Primitive (Subp) then 3144 Error_Msg_NE 3145 ("type& must be completed in the private part", 3146 Parent (Subp), Id); 3147 3148 -- The result type of an access-to-function type cannot be a 3149 -- Taft-amendment type, unless the version is Ada 2012 or 3150 -- later (see AI05-151). 3151 3152 elsif Ada_Version < Ada_2012 3153 and then Ekind (Subp) = E_Subprogram_Type 3154 then 3155 if Etype (Subp) = Id 3156 or else 3157 (Is_Class_Wide_Type (Etype (Subp)) 3158 and then Etype (Etype (Subp)) = Id) 3159 then 3160 Error_Msg_NE 3161 ("type& must be completed in the private part", 3162 Associated_Node_For_Itype (Subp), Id); 3163 end if; 3164 end if; 3165 3166 Next_Elmt (Elmt); 3167 end loop; 3168 end; 3169 3170 elsif not Is_Child_Unit (Id) 3171 and then (not Is_Private_Type (Id) or else No (Full_View (Id))) 3172 then 3173 Set_Is_Hidden (Id); 3174 Set_Is_Potentially_Use_Visible (Id, False); 3175 end if; 3176 3177 <<Next_Id>> 3178 Next_Entity (Id); 3179 end loop; 3180 end Uninstall_Declarations; 3181 3182 ------------------------ 3183 -- Unit_Requires_Body -- 3184 ------------------------ 3185 3186 function Unit_Requires_Body 3187 (Pack_Id : Entity_Id; 3188 Do_Abstract_States : Boolean := False) return Boolean 3189 is 3190 E : Entity_Id; 3191 3192 Requires_Body : Boolean := False; 3193 -- Flag set when the unit has at least one construct that requries 3194 -- completion in a body. 3195 3196 begin 3197 -- Imported entity never requires body. Right now, only subprograms can 3198 -- be imported, but perhaps in the future we will allow import of 3199 -- packages. 3200 3201 if Is_Imported (Pack_Id) then 3202 return False; 3203 3204 -- Body required if library package with pragma Elaborate_Body 3205 3206 elsif Has_Pragma_Elaborate_Body (Pack_Id) then 3207 return True; 3208 3209 -- Body required if subprogram 3210 3211 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then 3212 return True; 3213 3214 -- Treat a block as requiring a body 3215 3216 elsif Ekind (Pack_Id) = E_Block then 3217 return True; 3218 3219 elsif Ekind (Pack_Id) = E_Package 3220 and then Nkind (Parent (Pack_Id)) = N_Package_Specification 3221 and then Present (Generic_Parent (Parent (Pack_Id))) 3222 then 3223 declare 3224 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id)); 3225 begin 3226 if Has_Pragma_Elaborate_Body (G_P) then 3227 return True; 3228 end if; 3229 end; 3230 end if; 3231 3232 -- Traverse the entity chain of the package and look for constructs that 3233 -- require a completion in a body. 3234 3235 E := First_Entity (Pack_Id); 3236 while Present (E) loop 3237 3238 -- Skip abstract states because their completion depends on several 3239 -- criteria (see below). 3240 3241 if Ekind (E) = E_Abstract_State then 3242 null; 3243 3244 elsif Requires_Completion_In_Body 3245 (E, Pack_Id, Do_Abstract_States) 3246 then 3247 Requires_Body := True; 3248 exit; 3249 end if; 3250 3251 Next_Entity (E); 3252 end loop; 3253 3254 -- A [generic] package that defines at least one non-null abstract state 3255 -- requires a completion only when at least one other construct requires 3256 -- a completion in a body (SPARK RM 7.1.4(4) and (6)). This check is not 3257 -- performed if the caller requests this behavior. 3258 3259 if Do_Abstract_States 3260 and then Ekind_In (Pack_Id, E_Generic_Package, E_Package) 3261 and then Has_Non_Null_Abstract_State (Pack_Id) 3262 and then Requires_Body 3263 then 3264 return True; 3265 end if; 3266 3267 return Requires_Body; 3268 end Unit_Requires_Body; 3269 3270 ----------------------------- 3271 -- Unit_Requires_Body_Info -- 3272 ----------------------------- 3273 3274 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id) is 3275 E : Entity_Id; 3276 3277 begin 3278 -- An imported entity never requires body. Right now, only subprograms 3279 -- can be imported, but perhaps in the future we will allow import of 3280 -- packages. 3281 3282 if Is_Imported (Pack_Id) then 3283 return; 3284 3285 -- Body required if library package with pragma Elaborate_Body 3286 3287 elsif Has_Pragma_Elaborate_Body (Pack_Id) then 3288 Error_Msg_N ("info: & requires body (Elaborate_Body)?Y?", Pack_Id); 3289 3290 -- Body required if subprogram 3291 3292 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then 3293 Error_Msg_N ("info: & requires body (subprogram case)?Y?", Pack_Id); 3294 3295 -- Body required if generic parent has Elaborate_Body 3296 3297 elsif Ekind (Pack_Id) = E_Package 3298 and then Nkind (Parent (Pack_Id)) = N_Package_Specification 3299 and then Present (Generic_Parent (Parent (Pack_Id))) 3300 then 3301 declare 3302 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id)); 3303 begin 3304 if Has_Pragma_Elaborate_Body (G_P) then 3305 Error_Msg_N 3306 ("info: & requires body (generic parent Elaborate_Body)?Y?", 3307 Pack_Id); 3308 end if; 3309 end; 3310 3311 -- A [generic] package that introduces at least one non-null abstract 3312 -- state requires completion. However, there is a separate rule that 3313 -- requires that such a package have a reason other than this for a 3314 -- body being required (if necessary a pragma Elaborate_Body must be 3315 -- provided). If Ignore_Abstract_State is True, we don't do this check 3316 -- (so we can use Unit_Requires_Body to check for some other reason). 3317 3318 elsif Ekind_In (Pack_Id, E_Generic_Package, E_Package) 3319 and then Present (Abstract_States (Pack_Id)) 3320 and then not Is_Null_State 3321 (Node (First_Elmt (Abstract_States (Pack_Id)))) 3322 then 3323 Error_Msg_N 3324 ("info: & requires body (non-null abstract state aspect)?Y?", 3325 Pack_Id); 3326 end if; 3327 3328 -- Otherwise search entity chain for entity requiring completion 3329 3330 E := First_Entity (Pack_Id); 3331 while Present (E) loop 3332 if Requires_Completion_In_Body (E, Pack_Id) then 3333 Error_Msg_Node_2 := E; 3334 Error_Msg_NE 3335 ("info: & requires body (& requires completion)?Y?", E, Pack_Id); 3336 end if; 3337 3338 Next_Entity (E); 3339 end loop; 3340 end Unit_Requires_Body_Info; 3341 3342end Sem_Ch7; 3343