gcc/ada/ali.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                                  A L I                                   --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2002 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 2,  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 COPYING.  If not, write --
  19 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, USA.                                                      --
  21 --                                                                          --
  22 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 --  This package defines the internal data structures used for representation
  28 --  of Ada Library Information (ALI) acquired from the ALI files generated
  29 --  by the front end.
  30
  31 with Casing;  use Casing;
  32 with Gnatvsn; use Gnatvsn;
  33 with Rident;  use Rident;
  34 with Table;
  35 with Types;   use Types;
  36
  37 with GNAT.HTable; use GNAT.HTable;
  38
  39 package ALI is
  40
  41    --------------
  42    -- Id Types --
  43    --------------
  44
  45    --  The various entries are stored in tables with distinct subscript
  46    --  ranges. The following type definitions indicate the ranges used
  47    --  for the subscripts (Id values) for the various tables.
  48
  49    type ALI_Id is range 0 .. 999_999;
  50    --  Id values used for ALIs table entries
  51
  52    type Unit_Id is range 1_000_000 .. 1_999_999;
  53    --  Id values used for Unit table entries
  54
  55    type With_Id is range 2_000_000 .. 2_999_999;
  56    --  Id values used for Withs table entries
  57
  58    type Arg_Id is range 3_000_000 .. 3_999_999;
  59    --  Id values used for argument table entries
  60
  61    type Sdep_Id is range 4_000_000 .. 4_999_999;
  62    --  Id values used for Sdep table entries
  63
  64    type Source_Id is range 5_000_000 .. 5_999_999;
  65    --  Id values used for Source table entries
  66
  67    --------------------
  68    -- ALI File Table --
  69    --------------------
  70
  71    --  Each ALI file read generates an entry in the ALIs table
  72
  73    No_ALI_Id : constant ALI_Id := ALI_Id'First;
  74    --  Special value indicating no ALI entry
  75
  76    First_ALI_Entry : constant ALI_Id := No_ALI_Id + 1;
  77    --  Id of first actual entry in table
  78
  79    type Main_Program_Type is (None, Proc, Func);
  80    --  Indicator of whether unit can be used as main program
  81
  82    type Restrictions_String is array (All_Restrictions) of Character;
  83    --  Type used to hold string from R line
  84
  85    type ALIs_Record is record
  86
  87       Afile : File_Name_Type;
  88       --  Name of ALI file
  89
  90       Ofile_Full_Name : Name_Id;
  91       --  Full name of object file corresponding to the ALI file
  92
  93       Sfile : File_Name_Type;
  94       --  Name of source file that generates this ALI file (which is equal
  95       --  to the name of the source file in the first unit table entry for
  96       --  this ALI file, since the body if present is always first).
  97
  98       Ver : String (1 .. Ver_Len_Max);
  99       --  Value of library version (V line in ALI file)
 100
 101       Ver_Len : Natural;
 102       --  Length of characters stored in Ver
 103
 104       First_Unit : Unit_Id;
 105       --  Id of first Unit table entry for this file
 106
 107       Last_Unit : Unit_Id;
 108       --  Id of last Unit table entry for this file
 109
 110       First_Sdep : Sdep_Id;
 111       --  Id of first Sdep table entry for this file
 112
 113       Last_Sdep : Sdep_Id;
 114       --  Id of last Sdep table entry for this file
 115
 116       Main_Program : Main_Program_Type;
 117       --  Indicator of whether first unit can be used as main program
 118
 119       Main_Priority : Int;
 120       --  Indicates priority value if Main_Program field indicates that
 121       --  this can be a main program. A value of -1 (No_Main_Priority)
 122       --  indicates that no parameter was found, or no M line was present.
 123
 124       Time_Slice_Value : Int;
 125       --  Indicates value of time slice parameter from T=xxx on main program
 126       --  line. A value of -1 indicates that no T=xxx parameter was found,
 127       --  or no M line was present.
 128
 129       WC_Encoding : Character;
 130       --  Wide character encoding if main procedure. Otherwise not relevant.
 131
 132       Locking_Policy : Character;
 133       --  Indicates locking policy for units in this file. Space means
 134       --  tasking was not used, or that no Locking_Policy pragma was
 135       --  present or that this is a language defined unit. Otherwise set
 136       --  to first character (upper case) of policy name.
 137
 138       Queuing_Policy : Character;
 139       --  Indicates queuing policy for units in this file. Space means
 140       --  tasking was not used, or that no Queuing_Policy pragma was
 141       --  present or that this is a language defined unit. Otherwise set
 142       --  to first character (upper case) of policy name.
 143
 144       Task_Dispatching_Policy : Character;
 145       --  Indicates task dispatching policy for units in this file. Space
 146       --  means tasking was not used, or that no Task_Dispatching_Policy
 147       --  pragma was present or that this is a language defined unit.
 148       --  Otherwise set to first character (upper case) of policy name.
 149
 150       Compile_Errors : Boolean;
 151       --  Set to True if compile errors for unit. Note that No_Object
 152       --  will always be set as well in this case.
 153
 154       Float_Format : Character;
 155       --  Set to float format (set to I if no float-format given)
 156
 157       No_Object : Boolean;
 158       --  Set to True if no object file generated
 159
 160       No_Run_Time : Boolean;
 161       --  Set to True if file was compiled with pragma No_Run_Time
 162
 163       Normalize_Scalars : Boolean;
 164       --  Set to True if file was compiled with Normalize_Scalars
 165
 166       Unit_Exception_Table : Boolean;
 167       --  Set to True if unit exception table pointer generated
 168
 169       Zero_Cost_Exceptions : Boolean;
 170       --  Set to True if file was compiled with zero cost exceptions
 171
 172       Restrictions : Restrictions_String;
 173       --  Copy of restrictions letters from R line
 174
 175    end record;
 176
 177    No_Main_Priority : constant Int := -1;
 178    --  Code for no main priority set
 179
 180    package ALIs is new Table.Table (
 181      Table_Component_Type => ALIs_Record,
 182      Table_Index_Type     => ALI_Id,
 183      Table_Low_Bound      => First_ALI_Entry,
 184      Table_Initial        => 500,
 185      Table_Increment      => 200,
 186      Table_Name           => "ALIs");
 187
 188    ----------------
 189    -- Unit Table --
 190    ----------------
 191
 192    --  Each unit within an ALI file generates an entry in the unit table
 193
 194    No_Unit_Id : constant Unit_Id := Unit_Id'First;
 195    --  Special value indicating no unit table entry
 196
 197    First_Unit_Entry : constant Unit_Id := No_Unit_Id + 1;
 198    --  Id of first actual entry in table
 199
 200    type Unit_Type is (Is_Spec, Is_Body, Is_Spec_Only, Is_Body_Only);
 201    --  Indicates type of entry, if both body and spec appear in the ALI file,
 202    --  then the first unit is marked Is_Body, and the second is marked Is_Spec.
 203    --  If only a spec appears, then it is marked as Is_Spec_Only, and if only
 204    --  a body appears, then it is marked Is_Body_Only).
 205
 206    subtype Version_String is String (1 .. 8);
 207    --  Version string, taken from unit record
 208
 209    type Unit_Record is record
 210
 211       My_ALI : ALI_Id;
 212       --  Corresponding ALI entry
 213
 214       Uname : Unit_Name_Type;
 215       --  Name of Unit
 216
 217       Sfile : File_Name_Type;
 218       --  Name of source file
 219
 220       Preelab : Boolean;
 221       --  Indicates presence of PR parameter for a preelaborated package
 222
 223       No_Elab : Boolean;
 224       --  Indicates presence of NE parameter for a unit that has does not
 225       --  have an elaboration routine (since it has no elaboration code).
 226
 227       Pure : Boolean;
 228       --  Indicates presence of PU parameter for a pure package
 229
 230       Dynamic_Elab : Boolean;
 231       --  Set to True if the unit was compiled with dynamic elaboration
 232       --  checks (i.e. either -gnatE or pragma Elaboration_Checks (Static)
 233       --  was used to compile the unit).
 234
 235       Elaborate_Body : Boolean;
 236       --  Indicates presence of EB parameter for a package which has a
 237       --  pragma Preelaborate_Body.
 238
 239       Set_Elab_Entity : Boolean;
 240       --  Indicates presence of EE parameter for a unit which has an
 241       --  elaboration entity which must be set true as part of the
 242       --  elaboration of the entity.
 243
 244       Has_RACW : Boolean;
 245       --  Indicates presence of RA parameter for a package that declares
 246       --  at least one Remote Access to Class_Wide (RACW) object.
 247
 248       Remote_Types : Boolean;
 249       --  Indicates presence of RT parameter for a package which has a
 250       --  pragma Remote_Types.
 251
 252       Shared_Passive : Boolean;
 253       --  Indicates presence of SP parameter for a package which has a
 254       --  pragma Shared_Passive.
 255
 256       RCI : Boolean;
 257       --  Indicates presence of RC parameter for a package which has a
 258       --  pragma Remote_Call_Interface.
 259
 260       Predefined : Boolean;
 261       --  Indicates if unit is language predefined (or a child of such a unit)
 262
 263       Internal : Boolean;
 264       --  Indicates if unit is an internal unit (or a child of such a unit)
 265
 266       First_With : With_Id;
 267       --  Id of first withs table entry for this file
 268
 269       Last_With : With_Id;
 270       --  Id of last withs table entry for this file
 271
 272       First_Arg : Arg_Id;
 273       --  Id of first args table entry for this file
 274
 275       Last_Arg : Arg_Id;
 276       --  Id of last args table entry for this file
 277
 278       Utype : Unit_Type;
 279       --  Type of entry
 280
 281       Is_Generic : Boolean;
 282       --  True for generic unit (i.e. a generic declaration, or a generic
 283       --  body). False for a non-generic unit.
 284
 285       Unit_Kind : Character;
 286       --  Indicates the nature of the unit. 'p' for Packages and 's' for
 287       --  subprograms.
 288
 289       Version : Version_String;
 290       --  Version of unit
 291
 292       Icasing : Casing_Type;
 293       --  Indicates casing of identifiers in source file for this unit. This
 294       --  is used for informational output, and also for constructing the
 295       --  main unit if it is being built in Ada.
 296
 297       Kcasing : Casing_Type;
 298       --  Indicates casing of keyowords in source file for this unit. This
 299       --  is used for informational output, and also for constructing the
 300       --  main unit if it is being built in Ada.
 301
 302       Elab_Position : aliased Natural;
 303       --  Initialized to zero. Set non-zero when a unit is chosen and
 304       --  placed in the elaboration order. The value represents the
 305       --  ordinal position in the elaboration order.
 306
 307       Init_Scalars : Boolean;
 308       --  Set True if IS qualifier appears in ALI file, indicating that
 309       --  an Initialize_Scalars pragma applies to the unit.
 310
 311    end record;
 312
 313    package Units is new Table.Table (
 314      Table_Component_Type => Unit_Record,
 315      Table_Index_Type     => Unit_Id,
 316      Table_Low_Bound      => First_Unit_Entry,
 317      Table_Initial        => 100,
 318      Table_Increment      => 200,
 319      Table_Name           => "Unit");
 320
 321    --------------
 322    -- Switches --
 323    --------------
 324
 325    --  These switches record status information about ali files that
 326    --  have been read, for quick reference without searching tables.
 327
 328    Dynamic_Elaboration_Checks_Specified : Boolean := False;
 329    --  Set to False by Initialize_ALI. Set to True if Read_ALI reads
 330    --  a unit for which dynamic elaboration checking is enabled.
 331
 332    Float_Format_Specified : Character := ' ';
 333    --  Set to blank by Initialize_ALI. Set to appropriate float format
 334    --  character (V or I, see Opt.Float_Format) if an an ali file that
 335    --  is read contains an F line setting the floating point format.
 336
 337    Initialize_Scalars_Used : Boolean := False;
 338    --  Set True if an ali file contains the Initialize_Scalars flag
 339
 340    Locking_Policy_Specified : Character := ' ';
 341    --  Set to blank by Initialize_ALI. Set to the appropriate locking policy
 342    --  character if an ali file contains a P line setting the locking policy.
 343
 344    No_Normalize_Scalars_Specified : Boolean := False;
 345    --  Set to False by Initialize_ALI. Set to True if an ali file indicates
 346    --  that the file was compiled without normalize scalars.
 347
 348    No_Object_Specified : Boolean := False;
 349    --  Set to False by Initialize_ALI. Set to True if an ali file contains
 350    --  the No_Object flag.
 351
 352    Normalize_Scalars_Specified : Boolean := False;
 353    --  Set to False by Initialize_ALI. Set to True if an ali file indicates
 354    --  that the file was compiled in Normalize_Scalars mode.
 355
 356    No_Run_Time_Specified : Boolean := False;
 357    --  Set to False by Initialize_ALI, Set to True if an ali file indicates
 358    --  that the file was compiled in No_Run_Time mode.
 359
 360    Queuing_Policy_Specified : Character := ' ';
 361    --  Set to blank by Initialize_ALI. Set to the appropriate queuing policy
 362    --  character if an ali file contains a P line setting the queuing policy.
 363
 364    Restrictions : Restrictions_String := (others => 'n');
 365    --  This array records the cumulative contributions of R lines in all
 366    --  ali files. An entry is changed will be set to v if any ali file
 367    --  indicates that the restriction is violated, and otherwise will be
 368    --  set to r if the restriction is specified by some unit.
 369
 370    Static_Elaboration_Model_Used : Boolean := False;
 371    --  Set to False by Initialize_ALI. Set to True if any ALI file for a
 372    --  non-internal unit compiled with the static elaboration model is
 373    --  encountered.
 374
 375    Task_Dispatching_Policy_Specified : Character := ' ';
 376    --  Set to blank by Initialize_ALI. Set to the appropriate task dispatching
 377    --  policy character if an ali file contains a P line setting the
 378    --  task dispatching policy.
 379
 380    Unreserve_All_Interrupts_Specified : Boolean := False;
 381    --  Set to False by Initialize_ALI. Set to True if an ali file is read that
 382    --  has  P line specifying unreserve all interrupts mode.
 383
 384    Zero_Cost_Exceptions_Specified : Boolean := False;
 385    --  Set to False by Initialize_ALI. Set to True if an ali file is read that
 386    --  has a P line specifying the generation of zero cost exceptions.
 387
 388    -----------------
 389    -- Withs Table --
 390    -----------------
 391
 392    --  Each With line (W line) in an ALI file generates a Withs table entry
 393
 394    No_With_Id : constant With_Id := With_Id'First;
 395    --  Special value indicating no withs table entry
 396
 397    First_With_Entry : constant With_Id := No_With_Id + 1;
 398    --  Id of first actual entry in table
 399
 400    type With_Record is record
 401
 402       Uname : Unit_Name_Type;
 403       --  Name of Unit
 404
 405       Sfile : File_Name_Type;
 406       --  Name of source file, set to No_File in generic case
 407
 408       Afile : File_Name_Type;
 409       --  Name of ALI file, set to No_File in generic case
 410
 411       Elaborate : Boolean;
 412       --  Indicates presence of E parameter
 413
 414       Elaborate_All : Boolean;
 415       --  Indicates presence of EA parameter
 416
 417       Elab_All_Desirable : Boolean;
 418       --  Indicates presence of ED parameter
 419
 420    end record;
 421
 422    package Withs is new Table.Table (
 423      Table_Component_Type => With_Record,
 424      Table_Index_Type     => With_Id,
 425      Table_Low_Bound      => First_With_Entry,
 426      Table_Initial        => 5000,
 427      Table_Increment      => 200,
 428      Table_Name           => "Withs");
 429
 430    ---------------------
 431    -- Arguments Table --
 432    ---------------------
 433
 434    --  Each Arg line (A line) in an ALI file generates an Args table entry
 435
 436    No_Arg_Id : constant Arg_Id := Arg_Id'First;
 437    --  Special value indicating no args table entry
 438
 439    First_Arg_Entry : constant Arg_Id := No_Arg_Id + 1;
 440    --  Id of first actual entry in table
 441
 442    package Args is new Table.Table (
 443      Table_Component_Type => String_Ptr,
 444      Table_Index_Type     => Arg_Id,
 445      Table_Low_Bound      => First_Arg_Entry,
 446      Table_Initial        => 1000,
 447      Table_Increment      => 100,
 448      Table_Name           => "Args");
 449
 450    --------------------------
 451    -- Linker_Options Table --
 452    --------------------------
 453
 454    --  If an ALI file has one of more Linker_Options lines, then a single
 455    --  entry is made in this table. If more than one Linker_Options lines
 456    --  appears in a given ALI file, then the arguments are concatenated
 457    --  to form the entry in this table, using a NUL character as the
 458    --  separator, and a final NUL character is appended to the end.
 459
 460    type Linker_Option_Record is record
 461       Name : Name_Id;
 462       --  Name entry containing concatenated list of Linker_Options
 463       --  arguments separated by NUL and ended by NUL as described above.
 464
 465       Unit : Unit_Id;
 466       --  Unit_Id for the entry
 467
 468       Internal_File : Boolean;
 469       --  Set True if the linker options are from an internal file. This is
 470       --  used to insert certain standard entries after all the user entries
 471       --  but before the entries from the run-time.
 472
 473       Original_Pos : Positive;
 474       --  Keep track of original position in the linker options table. This
 475       --  is used to implement a stable sort when we sort the linker options
 476       --  table.
 477    end record;
 478
 479    --  Declare the Linker_Options Table
 480
 481    --  The indexes of active entries in this table range from 1 to the
 482    --  value of Linker_Options.Last. The zero'th element is for sort call.
 483
 484    package Linker_Options is new Table.Table (
 485      Table_Component_Type => Linker_Option_Record,
 486      Table_Index_Type     => Integer,
 487      Table_Low_Bound      => 0,
 488      Table_Initial        => 200,
 489      Table_Increment      => 400,
 490      Table_Name           => "Linker_Options");
 491
 492    -------------------------------------------
 493    -- External Version Reference Hash Table --
 494    -------------------------------------------
 495
 496    --  This hash table keeps track of external version reference strings
 497    --  as read from E lines in the ali file. The stored values do not
 498    --  include the terminating quote characters.
 499
 500    type Vindex is range 0 .. 98;
 501    --  Type to define range of headers
 502
 503    function SHash (S : String_Ptr) return Vindex;
 504    --  Hash function for this table
 505
 506    function SEq (F1, F2 : String_Ptr) return Boolean;
 507    --  Equality function for this table
 508
 509    package Version_Ref is new Simple_HTable (
 510      Header_Num => Vindex,
 511      Element    => Boolean,
 512      No_Element => False,
 513      Key        => String_Ptr,
 514      Hash       => SHash,
 515      Equal      => SEq);
 516
 517    ------------------------------------
 518    -- Sdep (Source Dependency) Table --
 519    ------------------------------------
 520
 521    --  Each source dependency (D line) in an ALI file generates an
 522    --  entry in the Sdep table.
 523
 524    No_Sdep_Id : constant Sdep_Id := Sdep_Id'First;
 525    --  Special value indicating no Sdep table entry
 526
 527    First_Sdep_Entry : constant Sdep_Id := No_Sdep_Id + 1;
 528    --  Id of first actual entry in table
 529
 530    type Sdep_Record is record
 531
 532       Sfile : File_Name_Type;
 533       --  Name of source file
 534
 535       Stamp : Time_Stamp_Type;
 536       --  Time stamp value. Note that this will be all zero characters
 537       --  for the dummy entries for missing or non-dependent files.
 538
 539       Checksum : Word;
 540       --  Checksum value. Note that this will be all zero characters
 541       --  for the dummy entries for missing or non-dependent files
 542
 543       Dummy_Entry : Boolean;
 544       --  Set True for dummy entries that correspond to missing files
 545       --  or files where no dependency relationship exists.
 546
 547       Subunit_Name : Name_Id;
 548       --  Name_Id for subunit name if present, else No_Name
 549
 550       Rfile : File_Name_Type;
 551       --  Reference file name. Same as Sfile unless a Source_Reference
 552       --  pragma was used, in which case it reflects the name used in
 553       --  the pragma.
 554
 555       Start_Line : Nat;
 556       --  Starting line number in file. Always 1, unless a Source_Reference
 557       --  pragma was used, in which case it reflects the line number value
 558       --  given in the pragma.
 559
 560    end record;
 561
 562    package Sdep is new Table.Table (
 563      Table_Component_Type => Sdep_Record,
 564      Table_Index_Type     => Sdep_Id,
 565      Table_Low_Bound      => First_Sdep_Entry,
 566      Table_Initial        => 5000,
 567      Table_Increment      => 200,
 568      Table_Name           => "Sdep");
 569
 570    ----------------------------
 571    -- Use of Name Table Info --
 572    ----------------------------
 573
 574    --  All unit names and file names are entered into the Names table. The
 575    --  Info fields of these entries are used as follows:
 576
 577    --    Unit name           Info field has Unit_Id of unit table entry
 578    --    ALI file name       Info field has ALI_Id of ALI table entry
 579    --    Source file name    Info field has Source_Id of source table entry
 580
 581    --------------------------
 582    -- Cross-Reference Data --
 583    --------------------------
 584
 585    --  The following table records cross-reference sections, there is one
 586    --  entry for each X header line in the ALI file for an xref section.
 587    --  Note that there will be no entries in this table if the Read_Xref
 588    --  parameter to Scan_ALI was set to False.
 589
 590    type Xref_Section_Record is record
 591       File_Num : Sdep_Id;
 592       --  Dependency number for file (entry in Sdep.Table)
 593
 594       File_Name : Name_Id;
 595       --  Name of file
 596
 597       First_Entity : Nat;
 598       --  First entry in Xref_Entity table
 599
 600       Last_Entity : Nat;
 601       --  Last entry in Xref_Entity table
 602
 603    end record;
 604
 605    package Xref_Section is new Table.Table (
 606      Table_Component_Type => Xref_Section_Record,
 607      Table_Index_Type     => Nat,
 608      Table_Low_Bound      => 1,
 609      Table_Initial        => 50,
 610      Table_Increment      => 300,
 611      Table_Name           => "Xref_Section");
 612
 613    --  The following is used to indicate whether a typeref field is present
 614    --  for the entity, and if so what kind of typeref field.
 615
 616    type Tref_Kind is (
 617      Tref_None,    --  No typeref present
 618      Tref_Access,  --  Access type typeref (points to designated type)
 619      Tref_Derived, --  Derived type typeref (points to parent type)
 620      Tref_Type);   --  All other cases
 621
 622    --  The following table records entities for which xrefs are recorded
 623
 624    type Xref_Entity_Record is record
 625       Line : Pos;
 626       --  Line number of definition
 627
 628       Etype : Character;
 629       --  Set to the identification character for the entity. See section
 630       --  "Cross-Reference Entity Identifiers in lib-xref.ads for details.
 631
 632       Col : Pos;
 633       --  Column number of definition
 634
 635       Lib : Boolean;
 636       --  True if entity is library level entity
 637
 638       Entity : Name_Id;
 639       --  Name of entity
 640
 641       Rref_Line : Nat;
 642       --  This field is set to the line number of a renaming reference if
 643       --  one is present, or to zero if no renaming reference is present
 644
 645       Rref_Col : Nat;
 646       --  This field is set to the column number of a renaming reference
 647       --  if one is present, or to zero if no renaming reference is present.
 648
 649       Tref : Tref_Kind;
 650       --  Indicates if a typeref is present, and if so what kind. Set to
 651       --  Tref_None if no typeref field is present.
 652
 653       Tref_File_Num : Sdep_Id;
 654       --  This field is set to No_Sdep_Id if no typeref is present, or
 655       --  if the typeref refers to an entity in standard. Otherwise it
 656       --  it is the dependency reference for the file containing the
 657       --  declaration of the typeref entity.
 658
 659       Tref_Line : Nat;
 660       --  This field is set to zero if no typeref is present, or if the
 661       --  typeref refers to an entity in standard. Otherwise it contains
 662       --  the line number of the declaration of the typeref entity.
 663
 664       Tref_Type : Character;
 665       --  This field is set to blank if no typeref is present, or if the
 666       --  typeref refers to an entity in standard. Otherwise it contains
 667       --  the identification character for the typeref entity. See section
 668       --  "Cross-Reference Entity Identifiers in lib-xref.ads for details.
 669
 670       Tref_Col : Nat;
 671       --  This field is set to zero if no typeref is present, or if the
 672       --  typeref refers to an entity in standard. Otherwise it contains
 673       --  the column number of the declaration of the parent type.
 674
 675       Tref_Standard_Entity : Name_Id;
 676       --  This field is set to No_Name if no typeref is present or if the
 677       --  typeref refers to a declared entity rather than an entity in
 678       --  package Standard. If there is a typeref that references an
 679       --  entity in package Standard, then this field is a Name_Id
 680       --  reference for the entity name.
 681
 682       First_Xref : Nat;
 683       --  Index into Xref table of first cross-reference
 684
 685       Last_Xref : Nat;
 686       --  Index into Xref table of last cross-reference. The value in
 687       --  Last_Xref can be less than the First_Xref value to indicate
 688       --  that no entries are present in the Xref Table.
 689    end record;
 690
 691    package Xref_Entity is new Table.Table (
 692      Table_Component_Type => Xref_Entity_Record,
 693      Table_Index_Type     => Nat,
 694      Table_Low_Bound      => 1,
 695      Table_Initial        => 500,
 696      Table_Increment      => 300,
 697      Table_Name           => "Xref_Entity");
 698
 699    --  The following table records actual cross-references
 700
 701    type Xref_Record is record
 702       File_Num : Sdep_Id;
 703       --  Set to the file dependency number for the cross-reference. Note
 704       --  that if no file entry is present explicitly, this is just a copy
 705       --  of the reference for the current cross-reference section.
 706
 707       Line : Pos;
 708       --  Line number for the reference
 709
 710       Rtype : Character;
 711       --  Indicates type of reference, using code used in ALI file:
 712       --    r = reference
 713       --    m = modification
 714       --    b = body entity
 715       --    c = completion of private or incomplete type
 716       --    x = type extension
 717       --    i = implicit reference
 718       --  See description in lib-xref.ads for further details
 719
 720       Col : Nat;
 721       --  Column number for the reference
 722
 723       --  Note: for instantiation references, Rtype is set to ' ', and Col is
 724       --  set to zero. One or more such entries can follow any other reference.
 725    end record;
 726
 727    package Xref is new Table.Table (
 728      Table_Component_Type => Xref_Record,
 729      Table_Index_Type     => Nat,
 730      Table_Low_Bound      => 1,
 731      Table_Initial        => 2000,
 732      Table_Increment      => 300,
 733      Table_Name           => "Xref");
 734
 735    --------------------------------------
 736    -- Subprograms for Reading ALI File --
 737    --------------------------------------
 738
 739    procedure Initialize_ALI;
 740    --  Initialize the ALI tables. Also resets all switch values to defaults.
 741
 742    function Scan_ALI
 743      (F         : File_Name_Type;
 744       T         : Text_Buffer_Ptr;
 745       Ignore_ED : Boolean;
 746       Err       : Boolean;
 747       Read_Xref : Boolean := False)
 748       return      ALI_Id;
 749    --  Given the text, T, of an ALI file, F, scan and store the information
 750    --  from the file, and return the Id of the resulting entry in the ALI
 751    --  table. Switch settings may be modified as described above in the
 752    --  switch description settings.
 753    --
 754    --    Ignore_ED is normally False. If set to True, it indicates that
 755    --    all ED (elaboration desirable) indications in the ALI file are
 756    --    to be ignored.
 757    --
 758    --    Err determines the action taken on an incorrectly formatted file.
 759    --    If Err is False, then an error message is output, and the program
 760    --    is terminated. If Err is True, then no error message is output,
 761    --    and No_ALI_Id is returned.
 762    --
 763    --    Read_XREF is set True to read and acquire the cross-reference
 764    --    information, otherwise the scan is terminated when a cross-
 765    --    reference line is encountered.
 766
 767 end ALI;