gcc/ada/opt.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                                  O P T                                   --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --          Copyright (C) 1992-2002, Free Software Foundation, Inc.         --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNAT was originally developed  by the GNAT team at  New York University. --
  31 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  32 --                                                                          --
  33 ------------------------------------------------------------------------------
  34
  35 --  This package contains global flags set by the initialization
  36 --  routine from the command line and referenced throughout the compiler,
  37 --  the binder, gnatmake or other GNAT tools. The comments indicate which
  38 --  options are used by which programs (GNAT, GNATBIND, GNATMAKE, etc).
  39
  40 with Hostparm;       use Hostparm;
  41 with Types;          use Types;
  42 with System.WCh_Con; use System.WCh_Con;
  43
  44 package Opt is
  45
  46    ----------------------------------------------
  47    -- Settings of Modes for Current Processing --
  48    ----------------------------------------------
  49
  50    --  The following mode values represent the current state of processing.
  51    --  The values set here are the default values. Unless otherwise noted,
  52    --  the value may be reset in Switch with an appropropiate switch. In
  53    --  some cases, the values can also be modified by pragmas, and in the
  54    --  case of some binder variables, Gnatbind.Scan_Bind_Arg may modify
  55    --  the default values.
  56
  57    Ada_Bind_File : Boolean := True;
  58    --  GNATBIND, GNATLINK
  59    --  Set True if binder file to be generated in Ada rather than C
  60
  61    Ada_95 : Boolean := True;
  62    --  GNAT
  63    --  Set True if operating in Ada 95 mode
  64    --  Set False if operating in Ada 83 mode
  65
  66    Ada_83 : Boolean := False;
  67    --  GNAT
  68    --  Set True if operating in Ada 83 mode
  69    --  Set False if operating in Ada 95 mode
  70
  71    Ada_Final_Suffix : constant String := "final";
  72    Ada_Final_Name : String_Ptr := new String'("ada" & Ada_Final_Suffix);
  73    --  GNATBIND
  74    --  The name of the procedure that performs the finalization at the end of
  75    --  execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
  76
  77    Ada_Init_Suffix : constant String := "init";
  78    Ada_Init_Name : String_Ptr := new String'("ada" & Ada_Init_Suffix);
  79    --  GNATBIND
  80    --  The name of the procedure that performs initialization at the start
  81    --  of execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
  82
  83    Ada_Main_Name_Suffix : constant String := "main";
  84    --  GNATBIND
  85    --  The suffix for Ada_Main_Name. Defined as a constant here so that it
  86    --  can be referenced in a uniform manner to create either the default
  87    --  value of Ada_Main_Name (declared below), or the non-default name
  88    --  set by Gnatbind.Scan_Bind_Arg.
  89
  90    Ada_Main_Name : String_Ptr := new String'("ada_" & Ada_Main_Name_Suffix);
  91    --  GNATBIND
  92    --  The name of the Ada package generated by the binder (when in Ada mode).
  93    --  This variable may be modified by Gnatbind.Scan_Bind_Arg.
  94
  95    Address_Clause_Overlay_Warnings : Boolean := True;
  96    --  GNAT
  97    --  Set False to disable address clause warnings
  98
  99    All_Errors_Mode : Boolean := False;
 100    --  GNAT
 101    --  Flag set to force display of multiple errors on a single line and
 102    --  also repeated error messages for references to undefined identifiers
 103    --  and certain other repeated error messages.
 104
 105    All_Sources : Boolean := False;
 106    --  GNATBIND
 107    --  Set to True to require all source files to be present. This flag is
 108    --  directly modified by gnatmake to affect the shared binder routines.
 109
 110    Alternate_Main_Name : String_Ptr := null;
 111    --  GNATBIND
 112    --  Set to non null when Bind_Alternate_Main_Name is True. This value
 113    --  is modified as needed by Gnatbind.Scan_Bind_Arg.
 114
 115    Assertions_Enabled : Boolean := False;
 116    --  GNAT
 117    --  Enable assertions made using pragma Assert.
 118
 119    Back_Annotate_Rep_Info : Boolean := False;
 120    --  GNAT
 121    --  If set True (by use of -gnatB), enables back annotation of
 122    --  representation information by gigi, even in -gnatc mode.
 123
 124    Bind_Alternate_Main_Name : Boolean := False;
 125    --  GNATBIND
 126    --  True if main should be called Alternate_Main_Name.all.
 127    --  This variable may be set to True by Gnatbind.Scan_Bind_Arg.
 128
 129    Bind_Main_Program : Boolean := True;
 130    --  GNATBIND
 131    --  Set to False if not binding main Ada program.
 132
 133    Bind_For_Library : Boolean := False;
 134    --  GNATBIND
 135    --  Set to True if the binder needs to generate a file designed for
 136    --  building a library. May be set to True by Gnatbind.Scan_Bind_Arg.
 137
 138    Bind_Only : Boolean := False;
 139    --  GNATMAKE
 140    --  Set to True to skip compile and link steps
 141    --  (except when Compile_Only and/or Link_Only are True).
 142
 143    Brief_Output : Boolean := False;
 144    --  GNAT, GNATBIND
 145    --  Force brief error messages to standard error, even if verbose mode is
 146    --  set (so that main error messages go to standard output).
 147
 148    Check_Object_Consistency : Boolean := False;
 149    --  GNATBIND, GNATMAKE
 150    --  Set to True to check whether every object file is consistent with
 151    --  its corresponding ada library information (ALI) file. An object
 152    --  file is inconsistent with the corresponding ALI file if the object
 153    --  file does not exist or if it has an older time stamp than the ALI file.
 154    --  Default above is for GNATBIND. GNATMAKE overrides this default to
 155    --  True (see Make.Initialize) since we normally do need to check source
 156    --  consistencies in gnatmake.
 157
 158    Check_Only : Boolean := False;
 159    --  GNATBIND
 160    --  Set to True to do checks only, no output of binder file.
 161
 162    Check_Readonly_Files : Boolean := False;
 163    --  GNATMAKE
 164    --  Set to True to check readonly files during the make process.
 165
 166    Check_Source_Files : Boolean := True;
 167    --  GNATBIND, GNATMAKE
 168    --  Set to True to enable consistency checking for any source files that
 169    --  are present (i.e. date must match the date in the library info file).
 170    --  Set to False for object file consistency check only. This flag is
 171    --  directly modified by gnatmake, to affect the shared binder routines.
 172
 173    Check_Switches : Boolean := False;
 174    --  GNATMAKE
 175    --  Set to True to check compiler options during the make process.
 176
 177    Check_Unreferenced : Boolean := False;
 178    --  GNAT
 179    --  Set to True to enable checking for unreferenced entities other
 180    --  than formal parameters (for which see Check_Unreferenced_Formals)
 181
 182    Check_Unreferenced_Formals : Boolean := False;
 183    --  GNAT
 184    --  Set True to check for unreferenced formals. This is turned
 185    --  on by -gnatwa/wf/wu and turned off by -gnatwA/wF/wU.
 186
 187    Check_Withs : Boolean := False;
 188    --  GNAT
 189    --  Set to True to enable checking for unused withs, and also the case
 190    --  of withing a package and using none of the entities in the package.
 191
 192    Compile_Only : Boolean := False;
 193    --  GNATMAKE
 194    --  Set to True to skip bind and link steps (except when Bind_Only is True)
 195
 196    Compress_Debug_Names : Boolean := False;
 197    --  GNAT
 198    --  Set to True if the option to compress debug information is set (-gnatC)
 199
 200    Config_File : Boolean := True;
 201    --  GNAT
 202    --  Set to False to inhibit reading and processing of gnat.adc file
 203
 204    Config_File_Name : String_Ptr := null;
 205    --  GNAT
 206    --  File name of configuration pragmas file (given by switch -gnatec)
 207
 208    Constant_Condition_Warnings : Boolean := False;
 209    --  GNAT
 210    --  Set to True to activate warnings on constant conditions
 211
 212    Create_Mapping_File : Boolean := False;
 213    --  GNATMAKE
 214    --  Set to True (-C switch) to indicate that gnatmake
 215    --  invokes the compiler with a mapping file (-gnatem compiler switch).
 216
 217    subtype Debug_Level_Value is Nat range 0 .. 3;
 218    Debugger_Level : Debug_Level_Value := 0;
 219    --  GNATBIND
 220    --  The value given to the -g parameter.
 221    --  The default value for -g with no value is 2
 222    --  This is usually ignored by GNATBIND, except in the VMS version
 223    --  where it is passed as an argument to __gnat_initialize to trigger
 224    --  the activation of the remote debugging interface (is this true???).
 225
 226    Debug_Generated_Code : Boolean := False;
 227    --  GNAT
 228    --  Set True (-gnatD switch) to debug generated expanded code instead
 229    --  of the original source code. Causes debugging information to be
 230    --  written with respect to the generated code file that is written.
 231
 232    Display_Compilation_Progress : Boolean := False;
 233    --  GNATMAKE
 234    --  Set True (-d switch) to display information on progress while compiling
 235    --  files. Internal flag to be used in conjunction with an IDE such as
 236    --  Glide.
 237
 238    type Distribution_Stub_Mode_Type is
 239    --  GNAT
 240      (No_Stubs,
 241       --  Normal mode, no generation/compilation of distribution stubs
 242
 243       Generate_Receiver_Stub_Body,
 244       --  The unit being compiled is the RCI body, and the compiler will
 245       --  generate the body for the receiver stubs and compile it.
 246
 247       Generate_Caller_Stub_Body);
 248       --  The unit being compiled is the RCI spec, and the compiler will
 249       --  generate the body for the caller stubs and compile it.
 250
 251    Distribution_Stub_Mode : Distribution_Stub_Mode_Type := No_Stubs;
 252    --  GNAT
 253    --  This enumeration variable indicates the five states of distribution
 254    --  annex stub generation/compilation.
 255
 256    Do_Not_Execute : Boolean := False;
 257    --  GNATMAKE
 258    --  Set to True if no actual compilations should be undertaken.
 259
 260    Dynamic_Elaboration_Checks : Boolean := False;
 261    --  GNAT
 262    --  Set True for dynamic elaboration checking mode, as set by the -gnatE
 263    --  switch or by the use of pragma Elaboration_Checks (Dynamic).
 264
 265    Elab_Dependency_Output : Boolean := False;
 266    --  GNATBIND
 267    --  Set to True to output complete list of elaboration constraints
 268
 269    Elab_Order_Output : Boolean := False;
 270    --  GNATBIND
 271    --  Set to True to output chosen elaboration order
 272
 273    Elab_Warnings : Boolean := False;
 274    --  GNAT
 275    --  Set to True to generate full elaboration warnings (-gnatwl)
 276
 277    Enable_Overflow_Checks : Boolean := False;
 278    --  GNAT
 279    --  Set to True if -gnato (enable overflow checks) switch is set,
 280    --  but not -gnatp.
 281
 282    type Exception_Mechanism_Type is (Setjmp_Longjmp, Front_End_ZCX, GCC_ZCX);
 283    pragma Convention (C, Exception_Mechanism_Type);
 284
 285    Exception_Mechanism : Exception_Mechanism_Type := Setjmp_Longjmp;
 286    --  GNAT
 287    --  Set to the appropriate value depending on the default as given in
 288    --  system.ads (ZCX_By_Default, GCC_ZCX_Support, Front_End_ZCX_Support)
 289    --  and the use of -gnatL -gnatZ (and -gnatdX). The C convention is
 290    --  there to make this variable accessible to gigi.
 291
 292    Exception_Tracebacks : Boolean := False;
 293    --  GNATBIND
 294    --  Set to True to store tracebacks in exception occurrences (-E)
 295
 296    Extensions_Allowed : Boolean := False;
 297    --  GNAT
 298    --  Set to True by switch -gnatX if GNAT specific language extensions
 299    --  are allowed. For example, "with type" is a GNAT extension.
 300
 301    type External_Casing_Type is (
 302      As_Is,       -- External names cased as they appear in the Ada source
 303      Uppercase,   -- External names forced to all uppercase letters
 304      Lowercase);  -- External names forced to all lowercase letters
 305
 306    External_Name_Imp_Casing : External_Casing_Type := Lowercase;
 307    --  GNAT
 308    --  The setting of this flag determines the casing of external names
 309    --  when the name is implicitly derived from an entity name (i.e. either
 310    --  no explicit External_Name or Link_Name argument is used, or, in the
 311    --  case of extended DEC pragmas, the external name is given using an
 312    --  identifier. The As_Is setting is not permitted here (since this would
 313    --  create Ada source programs that were case sensitive).
 314
 315    External_Name_Exp_Casing : External_Casing_Type := As_Is;
 316    --  GNAT
 317    --  The setting of this flag determines the casing of an external name
 318    --  specified explicitly with a string literal. As_Is means the string
 319    --  literal is used as given with no modification to the casing. If
 320    --  Lowercase or Uppercase is set, then the string is forced to all
 321    --  lowercase or all uppercase letters as appropriate. Note that this
 322    --  setting has no effect if the external name is given using an identifier
 323    --  in the case of extended DEC import/export pragmas (in this case the
 324    --  casing is controlled by External_Name_Imp_Casing), and also has no
 325    --  effect if an explicit Link_Name is supplied (a link name is always
 326    --  used exactly as given).
 327
 328    Float_Format : Character := ' ';
 329    --  GNAT
 330    --  A non-blank value indicates that a Float_Format pragma has been
 331    --  processed, in which case this variable is set to 'I' for IEEE or
 332    --  to 'V' for VAX. The setting of 'V' is only possible on OpenVMS
 333    --  versions of GNAT.
 334
 335    Float_Format_Long : Character := ' ';
 336    --  GNAT
 337    --  A non-blank value indicates that a Long_Float pragma has been
 338    --  processed (this pragma is recognized only in OpenVMS versions
 339    --  of GNAT), in which case this variable is set to D or G for
 340    --  D_Float or G_Float.
 341
 342    Force_ALI_Tree_File : Boolean := False;
 343    --  GNAT
 344    --  Force generation of ALI file even if errors are encountered.
 345    --  Also forces generation of tree file if -gnatt is also set.
 346
 347    Force_Compilations : Boolean := False;
 348    --  GNATMAKE
 349    --  Set to force recompilations even when the objects are up-to-date.
 350
 351    Force_RM_Elaboration_Order : Boolean := False;
 352    --  GNATBIND
 353    --  True if binding with forced RM elaboration order (-f switch set)
 354    --  Note: this is considered an obsolescent option, to be removed in
 355    --  some future release. It is no longer documented. The proper way
 356    --  to get this effect is to use -gnatE and suppress elab checks.
 357
 358    Full_List : Boolean := False;
 359    --  GNAT
 360    --  Set True to generate full source listing with embedded errors
 361
 362    Global_Discard_Names : Boolean := False;
 363    --  GNAT
 364    --  Set true if a pragma Discard_Names applies to the current unit
 365
 366    GNAT_Mode : Boolean := False;
 367    --  GNAT
 368    --  True if compiling in GNAT system mode (-gnatg switch)
 369
 370    HLO_Active : Boolean := False;
 371    --  GNAT
 372    --  True if High Level Optimizer is activated (-gnatH switch)
 373
 374    Implementation_Unit_Warnings : Boolean := True;
 375    --  GNAT
 376    --  Set True to active warnings for use of implementation internal units.
 377    --  Can be controlled by use of -gnatwi/-gnatwI.
 378
 379    Identifier_Character_Set : Character;
 380    --  GNAT
 381    --  This variable indicates the character set to be used for identifiers.
 382    --  The possible settings are:
 383    --    '1'  Latin-5 (ISO-8859-1)
 384    --    '2'  Latin-5 (ISO-8859-2)
 385    --    '3'  Latin-5 (ISO-8859-3)
 386    --    '4'  Latin-5 (ISO-8859-4)
 387    --    '5'  Latin-5 (ISO-8859-5, Cyrillic)
 388    --    '9'  Latin-5 (ISO-8859-9)
 389    --    'p'  PC (US, IBM page 437)
 390    --    '8'  PC (European, IBM page 850)
 391    --    'f'  Full upper set (all distinct)
 392    --    'n'  No upper characters (Ada/83 rules)
 393    --    'w'  Latin-1 plus wide characters allowed in identifiers
 394    --
 395    --  The setting affects the set of letters allowed in identifiers and the
 396    --  upper/lower case equivalences. It does not affect the interpretation of
 397    --  character and string literals, which are always stored using the actual
 398    --  coding in the source program. This variable is initialized to the
 399    --  default value appropriate to the system (in Osint.Initialize), and then
 400    --  reset if a command line switch is used to change the setting.
 401
 402    Ineffective_Inline_Warnings : Boolean := False;
 403    --  GNAT
 404    --  Set True to activate warnings if front-end inlining (-gnatN) is not
 405    --  able to actually inline a particular call (or all calls). Can be
 406    --  controlled by use of -gnatwp/-gnatwP.
 407
 408    Init_Or_Norm_Scalars : Boolean := False;
 409    --  GNAT
 410    --  Set True if a pragma Initialize_Scalars applies to the current unit.
 411    --  Also set True if a pragma Normalize_Scalars applies.
 412
 413    Initialize_Scalars : Boolean := False;
 414    --  GNAT
 415    --  Set True if a pragma Initialize_Scalars applies to the current unit.
 416    --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
 417
 418    Initialize_Scalars_Mode : Character := 'I';
 419    --  GNATBIND
 420    --  Set to 'I' for -Sin (default), 'L' for -Slo, 'H' for -Shi, 'X' for -Sxx
 421
 422    Initialize_Scalars_Val : String (1 .. 2);
 423    --  GNATBIND
 424    --  Valid only if Initialize_Scalars_Mode is set to 'X' (-Shh). Contains
 425    --  the two hex bytes from the -Shh switch.
 426
 427    Inline_Active : Boolean := False;
 428    --  GNAT
 429    --  Set True to activate pragma Inline processing across modules. Default
 430    --  for now is not to inline across module boundaries.
 431
 432    Front_End_Inlining : Boolean := False;
 433    --  GNAT
 434    --  Set True to activate inlining by front-end expansion.
 435
 436    Inline_Processing_Required : Boolean := False;
 437    --  GNAT
 438    --  Set True if inline processing is required. Inline processing is
 439    --  required if an active Inline pragma is processed. The flag is set
 440    --  for a pragma Inline or Inline_Always that is actually active.
 441
 442    In_Place_Mode : Boolean := False;
 443    --  GNATMAKE
 444    --  Set True to store ALI and object files in place ie in the object
 445    --  directory if these files already exist or in the source directory
 446    --  if not.
 447
 448    Keep_Going : Boolean := False;
 449    --  GNATMAKE
 450    --  When True signals gnatmake to ignore compilation errors and keep
 451    --  processing sources until there is no more work.
 452
 453    Link_Only : Boolean := False;
 454    --  GNATMAKE
 455    --  Set to True to skip compile and bind steps
 456    --  (except when Bind_Only is set to True).
 457
 458    List_Restrictions : Boolean := False;
 459    --  GNATBIND
 460    --  Set to True to list restrictions pragmas that could apply to partition
 461
 462    List_Units : Boolean := False;
 463    --  GNAT
 464    --  List units in the active library for a compilation (-gnatu switch)
 465
 466    List_Dependencies : Boolean := False;
 467    --  GNATMAKE
 468    --  When True gnatmake verifies that the objects are up to date and
 469    --  outputs the list of object dependencies (-M switch).
 470    --  Output depends if -a switch is used or not.
 471    --  This list can be used directly in a Makefile.
 472
 473    List_Representation_Info : Int range 0 .. 3 := 0;
 474    --  GNAT
 475    --  Set non-zero by -gnatR switch to list representation information.
 476    --  The settings are as follows:
 477    --
 478    --    0 = no listing of representation information (default as above)
 479    --    1 = list rep info for user defined record and array types
 480    --    2 = list rep info for all user defined types and objects
 481    --    3 = like 2, but variable fields are decoded symbolically
 482
 483    List_Representation_Info_To_File : Boolean := False;
 484    --  GNAT
 485    --  Set true by -gnatRs switch. Causes information from -gnatR/1/2/3
 486    --  to be written to file.rep (where file is the name of the source
 487    --  file) instead of stdout. For example, if file x.adb is compiled
 488    --  using -gnatR2s then representation info is written to x.adb.ref.
 489
 490    type Creat_Repinfo_File_Proc is access procedure (Src : File_Name_Type);
 491    type Write_Repinfo_Line_Proc is access procedure (Info : String);
 492    type Close_Repinfo_File_Proc is access procedure;
 493    --  Types used for procedure addresses below
 494
 495    Creat_Repinfo_File_Access : Creat_Repinfo_File_Proc := null;
 496    Write_Repinfo_Line_Access : Write_Repinfo_Line_Proc := null;
 497    Close_Repinfo_File_Access : Close_Repinfo_File_Proc := null;
 498    --  GNAT
 499    --  These three locations are left null when operating in non-compiler
 500    --  (e.g. ASIS mode), but when operating in compiler mode, they are
 501    --  set to point to the three corresponding procedures in Osint. The
 502    --  reason for this slightly strange interface is to prevent Repinfo
 503    --  from dragging in Osint in ASIS mode, which would include a lot of
 504    --  unwanted units in the ASIS build.
 505
 506    Locking_Policy : Character := ' ';
 507    --  GNAT
 508    --  Set to ' ' for the default case (no locking policy specified).
 509    --  Reset to first character (uppercase) of locking policy name if a
 510    --  valid pragma Locking_Policy is encountered.
 511
 512    Look_In_Primary_Dir : Boolean := True;
 513    --  GNAT, GNATBIND, GNATMAKE
 514    --  Set to False if a -I- was present on the command line.
 515    --  When True we are allowed to look in the primary directory to locate
 516    --  other source or library files.
 517
 518    Mapping_File_Name : String_Ptr := null;
 519    --  GNAT
 520    --  File name of mapping between unit names, file names and path names.
 521    --  (given by switch -gnatem)
 522
 523    Maximum_Errors : Int := 9999;
 524    --  GNAT, GNATBIND
 525    --  Maximum number of errors before compilation is terminated
 526
 527    Maximum_File_Name_Length : Int;
 528    --  GNAT, GNATBIND
 529    --  Maximum number of characters allowed in a file name, not counting the
 530    --  extension, as set by the appropriate switch. If no switch is given,
 531    --  then this value is initialized by Osint to the appropriate value.
 532
 533    Maximum_Processes : Positive := 1;
 534    --  GNATMAKE
 535    --  Maximum number of processes that should be spawned to carry out
 536    --  compilations.
 537
 538    Minimal_Recompilation : Boolean := False;
 539    --  GNATMAKE
 540    --  Set to True if minimal recompilation mode requested.
 541
 542    No_Stdlib : Boolean := False;
 543    --  GNATMAKE, GNATBIND, GNATFIND, GNATXREF
 544    --  Set to True if no default library search dirs added to search list.
 545
 546    No_Stdinc : Boolean := False;
 547    --  GNAT, GNATBIND, GNATMAKE, GNATFIND, GNATXREF
 548    --  Set to True if no default source search dirs added to search list.
 549
 550    No_Main_Subprogram : Boolean := False;
 551    --  GNATMAKE, GNATBIND
 552    --  Set to True if compilation/binding of a program without main
 553    --  subprogram requested.
 554
 555    Normalize_Scalars : Boolean := False;
 556    --  GNAT
 557    --  Set True if a pragma Normalize_Scalars applies to the current unit.
 558    --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
 559
 560    No_Run_Time : Boolean := False;
 561    --  GNAT
 562    --  Set True if a valid pragma No_Run_Time is processed or if the
 563    --  flag Targparm.High_Integrity_Mode_On_Target is set True.
 564
 565    type Operating_Mode_Type is (Check_Syntax, Check_Semantics, Generate_Code);
 566    Operating_Mode : Operating_Mode_Type := Generate_Code;
 567    --  GNAT
 568    --  Indicates the operating mode of the compiler. The default is generate
 569    --  code, which runs the parser, semantics and backend. Switches can be
 570    --  used to set syntax checking only mode, or syntax and semantics checking
 571    --  only mode. Operating_Mode can also be modified as a result of detecting
 572    --  errors during the compilation process. In particular if any error is
 573    --  detected then this flag is reset from Generate_Code to Check_Semantics
 574    --  after generating an error message.
 575
 576    Output_File_Name_Present : Boolean := False;
 577    --  GNATBIND, GNAT, GNATMAKE
 578    --  Set to True when the output C file name is given with option -o
 579    --  for GNATBIND, when the object file name is given with option
 580    --  -gnatO for GNAT or when the executable is given with option -o
 581    --  for GNATMAKE.
 582
 583    Output_Linker_Option_List : Boolean := False;
 584    --  GNATBIND
 585    --  True if output of list of linker options is requested (-K switch set)
 586
 587    Output_Object_List : Boolean := False;
 588    --  GNATBIND
 589    --  True if output of list of objects is requested (-O switch set)
 590
 591    Pessimistic_Elab_Order : Boolean := False;
 592    --  GNATBIND
 593    --  True if pessimistic elaboration order is to be chosen (-p switch set)
 594
 595    Polling_Required : Boolean := False;
 596    --  GNAT
 597    --  Set to True if polling for asynchronous abort is enabled by using
 598    --  the -gnatP option for GNAT.
 599
 600    Print_Generated_Code : Boolean := False;
 601    --  GNAT
 602    --  Set to True to enable output of generated code in source form. This
 603    --  flag is set by the -gnatG switch.
 604
 605    Propagate_Exceptions : Boolean := False;
 606    --  GNAT
 607    --  Indicates if subprogram descriptor exception tables should be
 608    --  built for imported subprograms. Set True if a Propagate_Exceptions
 609    --  pragma applies to the extended main unit.
 610
 611    Queuing_Policy : Character := ' ';
 612    --  GNAT
 613    --  Set to ' ' for the default case (no queuing policy specified).
 614    --  Reset to first character (uppercase) of locking policy name if a valid
 615    --  Queuing_Policy pragma is encountered.
 616
 617    Quiet_Output : Boolean := False;
 618    --  GNATMAKE
 619    --  Set to True if the list of compilation commands should not be output.
 620
 621    RTS_Switch : Boolean := False;
 622    --  GNAT, GNATMAKE, GNATBIND, GNATLS, GNATFIND, GNATXREF
 623    --  Set to True when the --RTS switch is set
 624
 625    Shared_Libgnat : Boolean;
 626    --  GNATBIND
 627    --  Set to True if a shared libgnat is requested by using the -shared
 628    --  option for GNATBIND and to False when using the -static option. The
 629    --  value of this flag is set by Gnatbind.Scan_Bind_Arg.
 630
 631    Stack_Checking_Enabled : Boolean;
 632    --  GNAT
 633    --  Set to indicate if -fstack-check switch is set for the compilation.
 634    --  True means that the switch is set, so that stack checking is enabled.
 635    --  False means that the switch is not set (no stack checking). This
 636    --  value is obtained from the external imported value flag_stack_check
 637    --  in the gcc backend (see Frontend) and may be referenced throughout
 638    --  the compilation phases.
 639
 640    Style_Check : Boolean := False;
 641    --  GNAT
 642    --  Set True to perform style checks. Activates checks carried out
 643    --  in package Style (see body of this package for details of checks)
 644    --  This flag is set True by either the -gnatg or -gnaty switches.
 645
 646    System_Extend_Pragma_Arg : Node_Id := Empty;
 647    --  GNAT
 648    --  Set non-empty if and only if a correct Extend_System pragma was present
 649    --  in which case it points to the argument of the pragma, and the name can
 650    --  be located as Chars (Expression (System_Extend_Pragma_Arg)).
 651
 652    Subunits_Missing : Boolean := False;
 653    --  GNAT
 654    --  This flag is set true if missing subunits are detected with code
 655    --  generation active. This causes code generation to be skipped.
 656
 657    Suppress_Checks : Boolean := False;
 658    --  GNAT
 659    --  Set to True if -gnatp (suppress all checks) switch present.
 660
 661    Suppress_Options : Suppress_Record;
 662    --  GNAT
 663    --  Flags set True to suppress corresponding check, i.e. add an implicit
 664    --  pragma Suppress at the outer level of each unit compiled. Note that
 665    --  these suppress actions can be overridden by the use of the Unsuppress
 666    --  pragma. This variable is initialized by Osint.Initialize.
 667
 668    Table_Factor : Int := 1;
 669    --  GNAT
 670    --  Factor by which all initial table sizes set in Alloc are multiplied.
 671    --  Used in Table to calculate initial table sizes (the initial table
 672    --  size is the value in Alloc, used as the Table_Initial parameter
 673    --  value, multiplied by the factor given here. The default value is
 674    --  used if no -gnatT switch appears.
 675
 676    Task_Dispatching_Policy : Character := ' ';
 677    --  GNAT
 678    --  Set to ' ' for the default case (no task dispatching policy specified).
 679    --  Reset to first character (uppercase) of task dispatching policy name
 680    --  if a valid Task_Dispatching_Policy pragma is encountered.
 681
 682    Tasking_Used : Boolean := False;
 683    --  Set True if any tasking construct is encountered. Used to activate the
 684    --  output of the Q, L and T lines in ALI files.
 685
 686    Time_Slice_Set : Boolean := False;
 687    --  GNATBIND
 688    --  Set True if a pragma Time_Slice is processed in the main unit, or
 689    --  if the -gnatTnn switch is present to set a time slice value.
 690
 691    Time_Slice_Value : Nat;
 692    --  GNATBIND
 693    --  Time slice value. Valid only if Time_Slice_Set is True, i.e. if a
 694    --  Time_Slice pragma has been processed. Set to the time slice value
 695    --  in microseconds. Negative values are stored as zero, and the value
 696    --  is not larger than 1_000_000_000 (1000 seconds). Values larger than
 697    --  this are reset to this maximum. This can also be set with the -gnatTnn
 698    --  switch.
 699
 700    Tolerate_Consistency_Errors : Boolean := False;
 701    --  GNATBIND
 702    --  Tolerate time stamp and other consistency errors. If this flag is
 703    --  set to True (-t), then inconsistencies result in warnings rather than
 704    --  errors.
 705
 706    Tree_Output : Boolean := False;
 707    --  GNAT
 708    --  Set to True (-gnatt) to generate output tree file
 709
 710    Try_Semantics : Boolean := False;
 711    --  GNAT
 712    --  Flag set to force attempt at semantic analysis, even if parser errors
 713    --  occur. This will probably cause blowups at this stage in the game. On
 714    --  the other hand, most such blowups will be caught cleanly and simply
 715    --  say compilation abandoned. This flag is set to True by -gnatq or -gnatQ.
 716
 717    Unique_Error_Tag : Boolean := Tag_Errors;
 718    --  GNAT
 719    --  Indicates if error messages are to be prefixed by the string error:
 720    --  Initialized from Tag_Errors, can be forced on with the -gnatU switch.
 721
 722    Unreserve_All_Interrupts : Boolean := False;
 723    --  GNAT, GNATBIND
 724    --  Normally set False, set True if a valid Unreserve_All_Interrupts
 725    --  pragma appears anywhere in the main unit for GNAT, or if any ALI
 726    --  file has the corresponding attribute set in GNATBIND.
 727
 728    Upper_Half_Encoding : Boolean := False;
 729    --  GNAT
 730    --  Normally set False, indicating that upper half ASCII characters are
 731    --  used in the normal way to represent themselves. If the wide character
 732    --  encoding method uses the upper bit for this encoding, then this flag
 733    --  is set True, and upper half characters in the source indicate the
 734    --  start of a wide character sequence.
 735
 736    Usage_Requested : Boolean := False;
 737    --  GNAT, GNATBIND, GNATMAKE
 738    --  Set to True if -h (-gnath for the compiler) switch encountered
 739    --  requesting usage information
 740
 741    Use_VADS_Size : Boolean := False;
 742    --  GNAT
 743    --  Set to True if a valid pragma Use_VADS_Size is processed
 744
 745    Validity_Checks_On  : Boolean := True;
 746    --  GNAT
 747    --  This flag determines if validity checking is on or off. The initial
 748    --  state is on, and the required default validity checks are active. The
 749    --  actual set of checks that is performed if Validity_Checks_On is set
 750    --  is defined by the switches in package Sem_Val. The Validity_Checks_On
 751    --  flag is controlled by pragma Validity_Checks (On | Off), and also
 752    --  some generated compiler code (typically code that has to do with
 753    --  validity check generation) is compiled with this flag set to False.
 754    --  This flag is set to False by the -gnatp switch.
 755
 756    Verbose_Mode : Boolean := False;
 757    --  GNAT, GNATBIND, GNATMAKE, GNATLINK, GNATLS, GNATCHOP, GNATNAME
 758    --  Set to True to get verbose mode (full error message text and location
 759    --  information sent to standard output, also header, copyright and summary)
 760
 761    Warn_On_Biased_Rounding : Boolean := False;
 762    --  GNAT
 763    --  Set to True to generate warnings for static constants that are rounded
 764    --  in a manner inconsistent with unbiased rounding (round to even). Can
 765    --  be modified by use of -gnatwb/B.
 766
 767    Warn_On_Dereference : Boolean := False;
 768    --  GNAT
 769    --  Set to True to generate warnings for implicit dereferences for array
 770    --  indexing and record component access. Modified by use of -gnatwd/D.
 771
 772    Warn_On_Hiding : Boolean := False;
 773    --  GNAT
 774    --  Set to True to generate warnings if a declared entity hides another
 775    --  entity. The default is that this warning is suppressed.
 776
 777    Warn_On_Redundant_Constructs : Boolean := False;
 778    --  GNAT
 779    --  Set to True to generate warnings for redundant constructs (e.g. useless
 780    --  assignments/conversions). The default is that this warning is disabled.
 781
 782    type Warning_Mode_Type is (Suppress, Normal, Treat_As_Error);
 783    Warning_Mode : Warning_Mode_Type := Normal;
 784    --  GNAT, GNATBIND
 785    --  Controls treatment of warning messages. If set to Suppress, warning
 786    --  messages are not generated at all. In Normal mode, they are generated
 787    --  but do not count as errors. In Treat_As_Error mode, warning messages
 788    --  are generated and are treated as errors.
 789
 790    Wide_Character_Encoding_Method : WC_Encoding_Method := WCEM_Brackets;
 791    --  GNAT
 792    --  Method used for encoding wide characters in the source program. See
 793    --  description of type in unit System.WCh_Con for a list of the methods
 794    --  that are currently supported. Note that brackets notation is always
 795    --  recognized in source programs regardless of the setting of this
 796    --  variable. The default setting causes only the brackets notation
 797    --  to be recognized. If this is the main unit, this setting also
 798    --  controls the output of the W=? parameter in the ALI file, which
 799    --  is used to provide the default for Wide_Text_IO files.
 800
 801    Xref_Active : Boolean := True;
 802    --  GNAT
 803    --  Set if cross-referencing is enabled (i.e. xref info in ALI files)
 804
 805    Zero_Cost_Exceptions_Val : Boolean;
 806    Zero_Cost_Exceptions_Set : Boolean := False;
 807    --  GNAT
 808    --  These values are to record the setting of the zero cost exception
 809    --  handling mode set by argument switches (-gnatZ/-gnatL). If the
 810    --  value is set by one of these switches, then Zero_Cost_Exceptions_Set
 811    --  is set to True, and Zero_Cost_Exceptions_Val indicates the setting.
 812
 813    ----------------------------
 814    -- Configuration Settings --
 815    ----------------------------
 816
 817    --  These are settings that are used to establish the mode at the start
 818    --  of each unit. The values defined below can be affected either by
 819    --  command line switches, or by the use of appropriate configuration
 820    --  pragmas in the gnat.adc file.
 821
 822    Ada_83_Config : Boolean;
 823    --  GNAT
 824    --  This is the value of the configuration switch for Ada 83 mode, as set
 825    --  by the command line switch -gnat83, and possibly modified by the use
 826    --  of configuration pragmas Ada_95 and Ada_83 in the gnat.adc file. This
 827    --  switch is used to set the initial value for Ada_83 mode at the start
 828    --  of analysis of a unit. Note however, that the setting of this flag
 829    --  is ignored for internal and predefined units (which are always compiled
 830    --  in Ada 95 mode).
 831
 832    Dynamic_Elaboration_Checks_Config : Boolean := False;
 833    --  GNAT
 834    --  Set True for dynamic elaboration checking mode, as set by the -gnatE
 835    --  switch or by the use of pragma Elaboration_Checking (Dynamic).
 836
 837    Extensions_Allowed_Config : Boolean;
 838    --  GNAT
 839    --  This is the flag that indicates whether extensions are allowed.
 840    --  It can be set True either by use of the -gnatX switch, or by use
 841    --  of the configuration pragma Extensions_Allowed (On). It is always
 842    --  set to True for internal GNAT units, since extensions are always
 843    --  permitted in such units.
 844
 845    External_Name_Exp_Casing_Config : External_Casing_Type;
 846    --  GNAT
 847    --  This is the value of the configuration switch that controls casing
 848    --  of external symbols for which an explicit external name is given. It
 849    --  can be set to Uppercase by the command line switch -gnatF, and further
 850    --  modified by the use of the configuration pragma External_Name_Casing
 851    --  in the gnat.adc file. This flag is used to set the initial value
 852    --  for External_Name_Exp_Casing at the start of analyzing each unit.
 853    --  Note however that the setting of this flag is ignored for internal
 854    --  and predefined units (which are always compiled with As_Is mode).
 855
 856    External_Name_Imp_Casing_Config : External_Casing_Type;
 857    --  GNAT
 858    --  This is the value of the configuration switch that controls casing
 859    --  of external symbols where the external name is implicitly given. It
 860    --  can be set to Uppercase by the command line switch -gnatF, and further
 861    --  modified by the use of the configuration pragma External_Name_Casing
 862    --  in the gnat.adc file. This flag is used to set the initial value
 863    --  for External_Name_Imp_Casing at the start of analyzing each unit.
 864    --  Note however that the setting of this flag is ignored for internal
 865    --  and predefined units (which are always compiled with Lowercase mode).
 866
 867    Polling_Required_Config : Boolean;
 868    --  GNAT
 869    --  This is the value of the configuration switch that controls polling
 870    --  mode. It can be set True by the command line switch -gnatP, and then
 871    --  further modified by the use of pragma Polling in the gnat.adc file.
 872    --  This flag is used to set the initial value for Polling_Required
 873    --  at the start of analyzing each unit.
 874
 875    Use_VADS_Size_Config : Boolean;
 876    --  GNAT
 877    --  This is the value of the configuration switch that controls the use
 878    --  of VADS_Size instead of Size whereever the attribute Size is used.
 879    --  It can be set True by the use of the pragma Use_VADS_Size in the
 880    --  gnat.adc file. This flag is used to set the initial value for
 881    --  Use_VADS_Size at the start of analyzing each unit. Note however that
 882    --  the setting of this flag is ignored for internal and predefined
 883    --  units (which are always compiled with the standard Size semantics).
 884
 885    type Config_Switches_Type is private;
 886    --  Type used to save values of the switches set from Config values
 887
 888    procedure Save_Opt_Config_Switches (Save : out Config_Switches_Type);
 889    --  This procedure saves the current values of the switches which are
 890    --  initialized from the above Config values, and then resets these
 891    --  switches according to the Config value settings.
 892
 893    procedure Set_Opt_Config_Switches (Internal_Unit : Boolean);
 894    --  This procedure sets the switches to the appropriate initial values.
 895    --  The parameter Internal_Unit is True for an internal or predefined
 896    --  unit, and affects the way the switches are set (see above).
 897
 898    procedure Restore_Opt_Config_Switches (Save : Config_Switches_Type);
 899    --  This procedure restores a set of switch values previously saved
 900    --  by a call to Save_Opt_Switches.
 901
 902    procedure Register_Opt_Config_Switches;
 903    --  This procedure is called after processing the gnat.adc file to record
 904    --  the values of the Config switches, as possibly modified by the use
 905    --  of command line switches and configuration pragmas.
 906
 907    ------------------------
 908    -- Other Global Flags --
 909    ------------------------
 910
 911    Expander_Active : Boolean := False;
 912    --  A flag that indicates if expansion is active (True) or deactivated
 913    --  (False). When expansion is deactivated all calls to expander routines
 914    --  have no effect. Note that the initial setting of False is merely to
 915    --  prevent saving of an undefined value for an initial call to the
 916    --  Expander_Mode_Save_And_Set procedure. For more information on the
 917    --  use of this flag, see package Expander. Indeed this flag might more
 918    --  logically be in the spec of Expander, but it is referenced by Errout,
 919    --  and it really seems wrong for Errout to depend on Expander.
 920
 921    -----------------------
 922    -- Tree I/O Routines --
 923    -----------------------
 924
 925    procedure Tree_Read;
 926    --  Reads switch settings from current tree file using Tree_Read
 927
 928    procedure Tree_Write;
 929    --  Writes out switch settings to current tree file using Tree_Write
 930
 931 private
 932
 933    type Config_Switches_Type is record
 934       Ada_83                     : Boolean;
 935       Dynamic_Elaboration_Checks : Boolean;
 936       Extensions_Allowed         : Boolean;
 937       External_Name_Exp_Casing   : External_Casing_Type;
 938       External_Name_Imp_Casing   : External_Casing_Type;
 939       Polling_Required           : Boolean;
 940       Use_VADS_Size              : Boolean;
 941    end record;
 942
 943 end Opt;