gcc/ada/opt.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                                  O P T                                   --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2004, 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 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNAT was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  This package contains global flags set by the initialization
  35 --  routine from the command line and referenced throughout the compiler,
  36 --  the binder, gnatmake or other GNAT tools. The comments indicate which
  37 --  options are used by which programs (GNAT, GNATBIND, GNATMAKE, etc).
  38
  39 with Gnatvsn;  use Gnatvsn;
  40 with Hostparm; use Hostparm;
  41 with Types;    use Types;
  42
  43 with System.WCh_Con; use System.WCh_Con;
  44 with GNAT.Strings;   use GNAT.Strings;
  45
  46 package Opt is
  47
  48    ----------------------------------------------
  49    -- Settings of Modes for Current Processing --
  50    ----------------------------------------------
  51
  52    --  The following mode values represent the current state of processing.
  53    --  The values set here are the default values. Unless otherwise noted,
  54    --  the value may be reset in Switch with an appropropiate switch. In
  55    --  some cases, the values can also be modified by pragmas, and in the
  56    --  case of some binder variables, Gnatbind.Scan_Bind_Arg may modify
  57    --  the default values.
  58
  59    Ada_Bind_File : Boolean := True;
  60    --  GNATBIND, GNATLINK
  61    --  Set True if binder file to be generated in Ada rather than C
  62
  63    Ada_95 : Boolean := True;
  64    --  GNAT
  65    --  Set True if operating in Ada 95 mode
  66    --  Set False if operating in Ada 83 mode
  67
  68    Ada_83 : Boolean := False;
  69    --  GNAT
  70    --  Set True if operating in Ada 83 mode
  71    --  Set False if operating in Ada 95 mode
  72
  73    Ada_Final_Suffix : constant String := "final";
  74    Ada_Final_Name : String_Ptr := new String'("ada" & Ada_Final_Suffix);
  75    --  GNATBIND
  76    --  The name of the procedure that performs the finalization at the end of
  77    --  execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
  78
  79    Ada_Init_Suffix : constant String := "init";
  80    Ada_Init_Name : String_Ptr := new String'("ada" & Ada_Init_Suffix);
  81    --  GNATBIND
  82    --  The name of the procedure that performs initialization at the start
  83    --  of execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
  84
  85    Ada_Main_Name_Suffix : constant String := "main";
  86    --  GNATBIND
  87    --  The suffix for Ada_Main_Name. Defined as a constant here so that it
  88    --  can be referenced in a uniform manner to create either the default
  89    --  value of Ada_Main_Name (declared below), or the non-default name
  90    --  set by Gnatbind.Scan_Bind_Arg.
  91
  92    Ada_Main_Name : String_Ptr := new String'("ada_" & Ada_Main_Name_Suffix);
  93    --  GNATBIND
  94    --  The name of the Ada package generated by the binder (when in Ada mode).
  95    --  This variable may be modified by Gnatbind.Scan_Bind_Arg.
  96
  97    Address_Clause_Overlay_Warnings : Boolean := True;
  98    --  GNAT
  99    --  Set False to disable address clause warnings
 100
 101    All_Errors_Mode : Boolean := False;
 102    --  GNAT
 103    --  Flag set to force display of multiple errors on a single line and
 104    --  also repeated error messages for references to undefined identifiers
 105    --  and certain other repeated error messages.
 106
 107    All_Sources : Boolean := False;
 108    --  GNATBIND
 109    --  Set to True to require all source files to be present. This flag is
 110    --  directly modified by gnatmake to affect the shared binder routines.
 111
 112    Alternate_Main_Name : String_Ptr := null;
 113    --  GNATBIND
 114    --  Set to non null when Bind_Alternate_Main_Name is True. This value
 115    --  is modified as needed by Gnatbind.Scan_Bind_Arg.
 116
 117    Assertions_Enabled : Boolean := False;
 118    --  GNAT
 119    --  Enable assertions made using pragma Assert.
 120
 121    ASIS_Mode : Boolean := False;
 122    --  GNAT
 123    --  Enable semantic checks and tree transformations that are important
 124    --  for ASIS but that are usually skipped if Operating_Mode is set to
 125    --  Check_Semantics. This flag does not have the corresponding option to set
 126    --  it ON. It is set ON when Tree_Output is set ON, it can also be set ON
 127    --  from the code of GNSA-based tool (a client may need to set ON the
 128    --  Back_Annotate_Rep_Info flag in this case. At the moment this does not
 129    --  make very much sense, because GNSA can not do back annotation).
 130
 131    Back_Annotate_Rep_Info : Boolean := False;
 132    --  GNAT
 133    --  If set True, enables back annotation of representation information
 134    --  by gigi, even in -gnatc mode. This is set True by the use of -gnatR
 135    --  (list representation information) or -gnatt (generate tree). It is
 136    --  also set true if certain Unchecked_Conversion instantiations require
 137    --  checking based on annotated values.
 138
 139    Bind_Alternate_Main_Name : Boolean := False;
 140    --  GNATBIND
 141    --  True if main should be called Alternate_Main_Name.all.
 142    --  This variable may be set to True by Gnatbind.Scan_Bind_Arg.
 143
 144    Bind_Main_Program : Boolean := True;
 145    --  GNATBIND
 146    --  Set to False if not binding main Ada program.
 147
 148    Bind_For_Library : Boolean := False;
 149    --  GNATBIND
 150    --  Set to True if the binder needs to generate a file designed for
 151    --  building a library. May be set to True by Gnatbind.Scan_Bind_Arg.
 152
 153    Bind_Only : Boolean := False;
 154    --  GNATMAKE
 155    --  Set to True to skip compile and link steps
 156    --  (except when Compile_Only and/or Link_Only are True).
 157
 158    Blank_Deleted_Lines : Boolean := False;
 159    --  GNAT, GNATPREP
 160    --  Output empty lines for each line of preprocessed input that is deleted
 161    --  in the output, including preprocessor lines starting with a '#'.
 162
 163    Brief_Output : Boolean := False;
 164    --  GNAT, GNATBIND
 165    --  Force brief error messages to standard error, even if verbose mode is
 166    --  set (so that main error messages go to standard output).
 167
 168    Build_Bind_And_Link_Full_Project : Boolean := False;
 169    --  GNATMAKE
 170    --  Set to True to build, bind and link all the sources of a project file
 171    --  (switch -B)
 172
 173    Check_Object_Consistency : Boolean := False;
 174    --  GNATBIND, GNATMAKE
 175    --  Set to True to check whether every object file is consistent with
 176    --  its corresponding ada library information (ALI) file. An object
 177    --  file is inconsistent with the corresponding ALI file if the object
 178    --  file does not exist or if it has an older time stamp than the ALI file.
 179    --  Default above is for GNATBIND. GNATMAKE overrides this default to
 180    --  True (see Make.Initialize) since we normally do need to check source
 181    --  consistencies in gnatmake.
 182
 183    Check_Only : Boolean := False;
 184    --  GNATBIND
 185    --  Set to True to do checks only, no output of binder file.
 186
 187    Check_Readonly_Files : Boolean := False;
 188    --  GNATMAKE
 189    --  Set to True to check readonly files during the make process.
 190
 191    Check_Source_Files : Boolean := True;
 192    --  GNATBIND, GNATMAKE
 193    --  Set to True to enable consistency checking for any source files that
 194    --  are present (i.e. date must match the date in the library info file).
 195    --  Set to False for object file consistency check only. This flag is
 196    --  directly modified by gnatmake, to affect the shared binder routines.
 197
 198    Check_Switches : Boolean := False;
 199    --  GNATMAKE
 200    --  Set to True to check compiler options during the make process.
 201
 202    Check_Unreferenced : Boolean := False;
 203    --  GNAT
 204    --  Set to True to enable checking for unreferenced entities other
 205    --  than formal parameters (for which see Check_Unreferenced_Formals)
 206
 207    Check_Unreferenced_Formals : Boolean := False;
 208    --  GNAT
 209    --  Set True to check for unreferenced formals. This is turned
 210    --  on by -gnatwa/wf/wu and turned off by -gnatwA/wF/wU.
 211
 212    Check_Withs : Boolean := False;
 213    --  GNAT
 214    --  Set to True to enable checking for unused withs, and also the case
 215    --  of withing a package and using none of the entities in the package.
 216
 217    Comment_Deleted_Lines : Boolean := False;
 218    --  GNATPREP
 219    --  True if source lines removed by the preprocessor should be commented
 220    --  in the output file.
 221
 222    Compile_Only : Boolean := False;
 223    --  GNATMAKE, GNATCLEAN
 224    --  GNATMAKE: set to True to skip bind and link steps (except when
 225    --            Bind_Only is True).
 226    --  GNATCLEAN: set to True to only the files produced by the compiler are to
 227    --             be deleted, but not the library files or executable files.
 228
 229    Config_File : Boolean := True;
 230    --  GNAT
 231    --  Set to False to inhibit reading and processing of gnat.adc file
 232
 233    Config_File_Names : String_List_Access := null;
 234    --  GNAT
 235    --  Names of configuration pragmas files (given by switches -gnatec)
 236
 237    Configurable_Run_Time_Mode : Boolean := False;
 238    --  GNAT, GNATBIND
 239    --  Set True if the compiler is operating in configurable run-time mode.
 240    --  This happens if the flag Targparm.Configurable_Run_TimeMode_On_Target
 241    --  is set True, or if pragma No_Run_Time is used. See the spec of Rtsfind
 242    --  for details on the handling of the latter pragma.
 243
 244    Constant_Condition_Warnings : Boolean := False;
 245    --  GNAT
 246    --  Set to True to activate warnings on constant conditions
 247
 248    Create_Mapping_File : Boolean := False;
 249    --  GNATMAKE
 250    --  Set to True (-C switch) to indicate that gnatmake
 251    --  invokes the compiler with a mapping file (-gnatem compiler switch).
 252
 253    subtype Debug_Level_Value is Nat range 0 .. 3;
 254    Debugger_Level : Debug_Level_Value := 0;
 255    --  GNATBIND
 256    --  The value given to the -g parameter.
 257    --  The default value for -g with no value is 2
 258    --  This is usually ignored by GNATBIND, except in the VMS version
 259    --  where it is passed as an argument to __gnat_initialize to trigger
 260    --  the activation of the remote debugging interface (is this true???).
 261
 262    Debug_Generated_Code : Boolean := False;
 263    --  GNAT
 264    --  Set True (-gnatD switch) to debug generated expanded code instead
 265    --  of the original source code. Causes debugging information to be
 266    --  written with respect to the generated code file that is written.
 267
 268    Default_Sec_Stack_Size : Int := -1;
 269    --  GNATBIND
 270    --  Set to default secondary stack size in units of kilobytes. Set by
 271    --  the -Dnnn switch for the binder. A value of -1 indicates that no
 272    --  default was set by the binder, and that the default should be the
 273    --  initial value of System.Secondary_Stack.Default_Secondary_Stack_Size.
 274
 275    Display_Compilation_Progress : Boolean := False;
 276    --  GNATMAKE
 277    --  Set True (-d switch) to display information on progress while compiling
 278    --  files. Internal flag to be used in conjunction with an IDE such as
 279    --  Glide.
 280
 281    type Distribution_Stub_Mode_Type is
 282    --  GNAT
 283      (No_Stubs,
 284       --  Normal mode, no generation/compilation of distribution stubs
 285
 286       Generate_Receiver_Stub_Body,
 287       --  The unit being compiled is the RCI body, and the compiler will
 288       --  generate the body for the receiver stubs and compile it.
 289
 290       Generate_Caller_Stub_Body);
 291       --  The unit being compiled is the RCI spec, and the compiler will
 292       --  generate the body for the caller stubs and compile it.
 293
 294    Distribution_Stub_Mode : Distribution_Stub_Mode_Type := No_Stubs;
 295    --  GNAT
 296    --  This enumeration variable indicates the five states of distribution
 297    --  annex stub generation/compilation.
 298
 299    Do_Not_Execute : Boolean := False;
 300    --  GNATMAKE
 301    --  Set to True if no actual compilations should be undertaken.
 302
 303    Dynamic_Elaboration_Checks : Boolean := False;
 304    --  GNAT
 305    --  Set True for dynamic elaboration checking mode, as set by the -gnatE
 306    --  switch or by the use of pragma Elaboration_Checks (Dynamic).
 307
 308    Elab_Dependency_Output : Boolean := False;
 309    --  GNATBIND
 310    --  Set to True to output complete list of elaboration constraints
 311
 312    Elab_Order_Output : Boolean := False;
 313    --  GNATBIND
 314    --  Set to True to output chosen elaboration order
 315
 316    Elab_Warnings : Boolean := False;
 317    --  GNAT
 318    --  Set to True to generate full elaboration warnings (-gnatwl)
 319
 320    Enable_Overflow_Checks : Boolean := False;
 321    --  GNAT
 322    --  Set to True if -gnato (enable overflow checks) switch is set,
 323    --  but not -gnatp.
 324
 325    Exception_Locations_Suppressed : Boolean := False;
 326    --  GNAT
 327    --  This flag is set True if a Suppress_Exception_Locations configuration
 328    --  pragma is currently active.
 329
 330    type Exception_Mechanism_Type is
 331    --  Determines the handling of exceptions. See Exp_Ch11 for details
 332    --
 333      (Front_End_Setjmp_Longjmp_Exceptions,
 334       --  Exceptions use setjmp/longjmp generated explicitly by the
 335       --  front end (this includes gigi or other equivalent parts of
 336       --  the code generator). AT END handlers are converted into
 337       --  exception handlers by the front end in this mode.
 338
 339       Front_End_ZCX_Exceptions,
 340       --  Exceptions use the zero cost table mechanism with explicit
 341       --  tables and exception regions generated by the front end.
 342       --  AT END handlers are converted into exception handlers by
 343       --  the front end in this mode.
 344
 345       Back_End_ZCX_Exceptions);
 346       --  Exceptions are handled by the back end. The front end simply
 347       --  generates the handlers as they appear in the source, and AT
 348       --  END handlers are left untouched (they are not converted into
 349       --  exception handlers when operating in this mode. Note that the
 350       --  name includes ZCX, since the expectation is that the back end
 351       --  mechanism will in fact be a ZCX approach, but nothing in the
 352       --  compiler depends on this, so for example if GNAT is run with
 353       --  a version of GCC configured for setjmp/longjmp exception handling,
 354       --  then everything will work fine.
 355    pragma Convention (C, Exception_Mechanism_Type);
 356
 357    Exception_Mechanism : Exception_Mechanism_Type :=
 358                            Front_End_Setjmp_Longjmp_Exceptions;
 359    --  GNAT
 360    --  Set to the appropriate value depending on the default as given in
 361    --  system.ads (ZCX_By_Default, GCC_ZCX_Support, Front_End_ZCX_Support)
 362    --  and the use of -gnatL -gnatZ (and -gnatdX). The C convention is
 363    --  there to make this variable accessible to gigi.
 364
 365    Exception_Tracebacks : Boolean := False;
 366    --  GNATBIND
 367    --  Set to True to store tracebacks in exception occurrences (-E)
 368
 369    Extensions_Allowed : Boolean := False;
 370    --  GNAT
 371    --  Set to True by switch -gnatX if GNAT specific language extensions
 372    --  are allowed. For example, "with type" is a GNAT extension.
 373
 374    type External_Casing_Type is (
 375      As_Is,       -- External names cased as they appear in the Ada source
 376      Uppercase,   -- External names forced to all uppercase letters
 377      Lowercase);  -- External names forced to all lowercase letters
 378
 379    External_Name_Imp_Casing : External_Casing_Type := Lowercase;
 380    --  GNAT
 381    --  The setting of this flag determines the casing of external names
 382    --  when the name is implicitly derived from an entity name (i.e. either
 383    --  no explicit External_Name or Link_Name argument is used, or, in the
 384    --  case of extended DEC pragmas, the external name is given using an
 385    --  identifier. The As_Is setting is not permitted here (since this would
 386    --  create Ada source programs that were case sensitive).
 387
 388    External_Name_Exp_Casing : External_Casing_Type := As_Is;
 389    --  GNAT
 390    --  The setting of this flag determines the casing of an external name
 391    --  specified explicitly with a string literal. As_Is means the string
 392    --  literal is used as given with no modification to the casing. If
 393    --  Lowercase or Uppercase is set, then the string is forced to all
 394    --  lowercase or all uppercase letters as appropriate. Note that this
 395    --  setting has no effect if the external name is given using an identifier
 396    --  in the case of extended DEC import/export pragmas (in this case the
 397    --  casing is controlled by External_Name_Imp_Casing), and also has no
 398    --  effect if an explicit Link_Name is supplied (a link name is always
 399    --  used exactly as given).
 400
 401    External_Unit_Compilation_Allowed : Boolean := False;
 402    --  GNATMAKE
 403    --  When True (set by gnatmake switch -x), allow compilation of sources
 404    --  that are not part of any project file.
 405
 406    Float_Format : Character := ' ';
 407    --  GNAT
 408    --  A non-blank value indicates that a Float_Format pragma has been
 409    --  processed, in which case this variable is set to 'I' for IEEE or
 410    --  to 'V' for VAX. The setting of 'V' is only possible on OpenVMS
 411    --  versions of GNAT.
 412
 413    Float_Format_Long : Character := ' ';
 414    --  GNAT
 415    --  A non-blank value indicates that a Long_Float pragma has been
 416    --  processed (this pragma is recognized only in OpenVMS versions
 417    --  of GNAT), in which case this variable is set to D or G for
 418    --  D_Float or G_Float.
 419
 420    Force_ALI_Tree_File : Boolean := False;
 421    --  GNAT
 422    --  Force generation of ALI file even if errors are encountered.
 423    --  Also forces generation of tree file if -gnatt is also set.
 424
 425    Force_Checking_Of_Elaboration_Flags : Boolean := False;
 426    --  GNATBIND
 427    --  True if binding with forced checking of the elaboration flags
 428    --  (-F switch set).
 429
 430    Force_Compilations : Boolean := False;
 431    --  GNATMAKE
 432    --  Set to force recompilations even when the objects are up-to-date.
 433
 434    Force_RM_Elaboration_Order : Boolean := False;
 435    --  GNATBIND
 436    --  True if binding with forced RM elaboration order (-f switch set)
 437    --  Note: this is considered an obsolescent option, to be removed in
 438    --  some future release. It is no longer documented. The proper way
 439    --  to get this effect is to use -gnatE and suppress elab checks.
 440
 441    Full_Path_Name_For_Brief_Errors : Boolean := False;
 442    --  GNAT, GNATMAKE, GNATCLEAN
 443    --  When True, in Brief_Output mode, each error message line
 444    --  will start with the full path name of the source.
 445    --  When False, only the file name without directory information
 446    --  is used.
 447
 448    Full_List : Boolean := False;
 449    --  GNAT
 450    --  Set True to generate full source listing with embedded errors
 451
 452    function get_gcc_version return Int;
 453    pragma Import (C, get_gcc_version, "get_gcc_version");
 454
 455    GCC_Version : constant Nat := get_gcc_version;
 456    --  GNATMAKE
 457    --  Indicates which version of gcc is in use (2 = 2.8.1, 3 = 3.x).
 458    --  Used in particular to decide if gcc switch -shared-libgcc should be
 459    --  used (it cannot be used for 2.8.1).
 460
 461    Global_Discard_Names : Boolean := False;
 462    --  GNAT, GNATBIND
 463    --  Set true if a pragma Discard_Names applies to the current unit
 464
 465    GNAT_Mode : Boolean := False;
 466    --  GNAT
 467    --  True if compiling in GNAT system mode (-gnatg switch)
 468
 469    HLO_Active : Boolean := False;
 470    --  GNAT
 471    --  True if High Level Optimizer is activated (-gnatH switch)
 472
 473    Implementation_Unit_Warnings : Boolean := True;
 474    --  GNAT
 475    --  Set True to active warnings for use of implementation internal units.
 476    --  Can be controlled by use of -gnatwi/-gnatwI.
 477
 478    Identifier_Character_Set : Character;
 479    --  GNAT
 480    --  This variable indicates the character set to be used for identifiers.
 481    --  The possible settings are:
 482    --    '1'  Latin-5 (ISO-8859-1)
 483    --    '2'  Latin-5 (ISO-8859-2)
 484    --    '3'  Latin-5 (ISO-8859-3)
 485    --    '4'  Latin-5 (ISO-8859-4)
 486    --    '5'  Latin-5 (ISO-8859-5, Cyrillic)
 487    --    '9'  Latin-5 (ISO-8859-9)
 488    --    'p'  PC (US, IBM page 437)
 489    --    '8'  PC (European, IBM page 850)
 490    --    'f'  Full upper set (all distinct)
 491    --    'n'  No upper characters (Ada/83 rules)
 492    --    'w'  Latin-1 plus wide characters allowed in identifiers
 493    --
 494    --  The setting affects the set of letters allowed in identifiers and the
 495    --  upper/lower case equivalences. It does not affect the interpretation of
 496    --  character and string literals, which are always stored using the actual
 497    --  coding in the source program. This variable is initialized to the
 498    --  default value appropriate to the system (in Osint.Initialize), and then
 499    --  reset if a command line switch is used to change the setting.
 500
 501    Ineffective_Inline_Warnings : Boolean := False;
 502    --  GNAT
 503    --  Set True to activate warnings if front-end inlining (-gnatN) is not
 504    --  able to actually inline a particular call (or all calls). Can be
 505    --  controlled by use of -gnatwp/-gnatwP.
 506
 507    Init_Or_Norm_Scalars : Boolean := False;
 508    --  GNAT, GANTBIND
 509    --  Set True if a pragma Initialize_Scalars applies to the current unit.
 510    --  Also set True if a pragma Normalize_Scalars applies.
 511
 512    Initialize_Scalars : Boolean := False;
 513    --  GNAT
 514    --  Set True if a pragma Initialize_Scalars applies to the current unit.
 515    --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
 516
 517    Initialize_Scalars_Mode1 : Character := 'I';
 518    Initialize_Scalars_Mode2 : Character := 'N';
 519    --  GNATBIND
 520    --  Set to two characters from -S switch (IN/LO/HI/EV/xx). The default
 521    --  is IN (invalid values), used if no -S switch is used.
 522
 523    Inline_Active : Boolean := False;
 524    --  GNAT
 525    --  Set True to activate pragma Inline processing across modules. Default
 526    --  for now is not to inline across module boundaries.
 527
 528    Interface_Library_Unit : Boolean := False;
 529    --  GNATBIND
 530    --  Set to True to indicate that at least one ALI file is an interface ALI:
 531    --  then elaboration flag checks are to be generated in the binder
 532    --  generated file.
 533
 534    Follow_Links : Boolean := False;
 535    --  GNATMAKE
 536    --  Set to True (-eL) to process the project files in trusted mode
 537
 538    Front_End_Inlining : Boolean := False;
 539    --  GNAT
 540    --  Set True to activate inlining by front-end expansion.
 541
 542    Inline_Processing_Required : Boolean := False;
 543    --  GNAT
 544    --  Set True if inline processing is required. Inline processing is
 545    --  required if an active Inline pragma is processed. The flag is set
 546    --  for a pragma Inline or Inline_Always that is actually active.
 547
 548    In_Place_Mode : Boolean := False;
 549    --  GNATMAKE
 550    --  Set True to store ALI and object files in place ie in the object
 551    --  directory if these files already exist or in the source directory
 552    --  if not.
 553
 554    Keep_Going : Boolean := False;
 555    --  GNATMAKE
 556    --  When True signals gnatmake to ignore compilation errors and keep
 557    --  processing sources until there is no more work.
 558
 559    Link_Only : Boolean := False;
 560    --  GNATMAKE
 561    --  Set to True to skip compile and bind steps
 562    --  (except when Bind_Only is set to True).
 563
 564    List_Restrictions : Boolean := False;
 565    --  GNATBIND
 566    --  Set to True to list restrictions pragmas that could apply to partition
 567
 568    List_Units : Boolean := False;
 569    --  GNAT
 570    --  List units in the active library for a compilation (-gnatu switch)
 571
 572    List_Dependencies : Boolean := False;
 573    --  GNATMAKE
 574    --  When True gnatmake verifies that the objects are up to date and
 575    --  outputs the list of object dependencies (-M switch).
 576    --  Output depends if -a switch is used or not.
 577    --  This list can be used directly in a Makefile.
 578
 579    List_Representation_Info : Int range 0 .. 3 := 0;
 580    --  GNAT
 581    --  Set non-zero by -gnatR switch to list representation information.
 582    --  The settings are as follows:
 583    --
 584    --    0 = no listing of representation information (default as above)
 585    --    1 = list rep info for user defined record and array types
 586    --    2 = list rep info for all user defined types and objects
 587    --    3 = like 2, but variable fields are decoded symbolically
 588
 589    List_Representation_Info_To_File : Boolean := False;
 590    --  GNAT
 591    --  Set true by -gnatRs switch. Causes information from -gnatR/1/2/3
 592    --  to be written to file.rep (where file is the name of the source
 593    --  file) instead of stdout. For example, if file x.adb is compiled
 594    --  using -gnatR2s then representation info is written to x.adb.ref.
 595
 596    List_Representation_Info_Mechanisms : Boolean := False;
 597    --  GNAT
 598    --  Set true by -gnatRm switch. Causes information on mechanisms to
 599    --  be included in the representation output information.
 600
 601    List_Preprocessing_Symbols : Boolean := False;
 602    --  GNAT, GNATPREP
 603    --  Set to True if symbols for preprocessing a source are to be listed
 604    --  before preprocessing occurs. Set to True by switch -s of gnatprep
 605    --  or -s in preprocessing data file for the compiler.
 606
 607    type Creat_Repinfo_File_Proc is access procedure (Src : File_Name_Type);
 608    type Write_Repinfo_Line_Proc is access procedure (Info : String);
 609    type Close_Repinfo_File_Proc is access procedure;
 610    --  Types used for procedure addresses below
 611
 612    Creat_Repinfo_File_Access : Creat_Repinfo_File_Proc := null;
 613    Write_Repinfo_Line_Access : Write_Repinfo_Line_Proc := null;
 614    Close_Repinfo_File_Access : Close_Repinfo_File_Proc := null;
 615    --  GNAT
 616    --  These three locations are left null when operating in non-compiler
 617    --  (e.g. ASIS mode), but when operating in compiler mode, they are
 618    --  set to point to the three corresponding procedures in Osint. The
 619    --  reason for this slightly strange interface is to prevent Repinfo
 620    --  from dragging in Osint in ASIS mode, which would include a lot of
 621    --  unwanted units in the ASIS build.
 622
 623    Locking_Policy : Character := ' ';
 624    --  GNAT, GNATBIND
 625    --  Set to ' ' for the default case (no locking policy specified).
 626    --  Reset to first character (uppercase) of locking policy name if a
 627    --  valid pragma Locking_Policy is encountered.
 628
 629    Locking_Policy_Sloc : Source_Ptr := No_Location;
 630    --  GNAT, GNATBIND
 631    --  Remember location of previous Locking_Policy pragma. This is used
 632    --  for inconsistency error messages. A value of System_Location is
 633    --  used if the policy is set in package System.
 634
 635    Look_In_Primary_Dir : Boolean := True;
 636    --  GNAT, GNATBIND, GNATMAKE, GNATCLEAN
 637    --  Set to False if a -I- was present on the command line.
 638    --  When True we are allowed to look in the primary directory to locate
 639    --  other source or library files.
 640
 641    Make_Steps : Boolean := False;
 642    --  GNATMAKE
 643    --  Set to True when either Compile_Only, Bind_Only or Link_Only is
 644    --  set to True.
 645
 646    Main_Index : Int := 0;
 647    --  GNATMAKE
 648    --  This is set to non-zero by gnatmake switch -eInnn to indicate that
 649    --  the main program is the nnn unit in a multi-unit source file.
 650
 651    Mapping_File_Name : String_Ptr := null;
 652    --  GNAT
 653    --  File name of mapping between unit names, file names and path names.
 654    --  (given by switch -gnatem)
 655
 656    Maximum_Errors : Int := 9999;
 657    --  GNAT, GNATBIND
 658    --  Maximum default number of errors before compilation is terminated.
 659    --  Can be overridden using -gnatm (GNAT) or -m (GNATBIND) switch.
 660
 661    Maximum_File_Name_Length : Int;
 662    --  GNAT, GNATBIND
 663    --  Maximum number of characters allowed in a file name, not counting the
 664    --  extension, as set by the appropriate switch. If no switch is given,
 665    --  then this value is initialized by Osint to the appropriate value.
 666
 667    Max_Line_Length : Int := Hostparm.Max_Line_Length;
 668    --  This is a copy of Max_Line_Length used by the scanner. It is usually
 669    --  set to be a copy of Hostparm.Max_Line_Length, and is used to check
 670    --  the maximum line length in the scanner when style checking is inactive.
 671    --  The only time it is set to a different value is during the scanning of
 672    --  configuration pragma files, where we want to turn off all checking and
 673    --  in particular we want to allow long lines. So we reset this value to
 674    --  Column_Number'Last during scanning of configuration pragma files.
 675
 676    Maximum_Processes : Positive := 1;
 677    --  GNATMAKE
 678    --  Maximum number of processes that should be spawned to carry out
 679    --  compilations.
 680
 681    Minimal_Recompilation : Boolean := False;
 682    --  GNATMAKE
 683    --  Set to True if minimal recompilation mode requested.
 684
 685    Multiple_Unit_Index : Int;
 686    --  GNAT
 687    --  This is set non-zero if the current unit is being compiled in multiple
 688    --  unit per file mode, meaning that the current unit is selected from the
 689    --  sequence of units in the current source file, using the value stored
 690    --  in this variable (e.g. 2 = select second unit in file). A value of
 691    --  zero indicates that we are in normal (one unit per file) mode.
 692
 693    No_Main_Subprogram : Boolean := False;
 694    --  GNATMAKE, GNATBIND
 695    --  Set to True if compilation/binding of a program without main
 696    --  subprogram requested.
 697
 698    No_Run_Time_Mode : Boolean := False;
 699    --  GNAT, GNATBIND
 700    --  This flag is set True if a No_Run_Time pragma is encountered. See
 701    --  spec of Rtsfind for a full description of handling of this pragma.
 702
 703    No_Stdinc : Boolean := False;
 704    --  GNAT, GNATBIND, GNATMAKE, GNATFIND, GNATXREF
 705    --  Set to True if no default source search dirs added to search list
 706
 707    No_Stdlib : Boolean := False;
 708    --  GNATMAKE, GNATBIND, GNATFIND, GNATXREF
 709    --  Set to True if no default library search dirs added to search list
 710
 711    No_Strict_Aliasing : Boolean := False;
 712    --  GNAT
 713    --  Set True if pragma No_Strict_Aliasing with no parameters encountered
 714
 715    Normalize_Scalars : Boolean := False;
 716    --  GNAT, GNATBIND
 717    --  Set True if a pragma Normalize_Scalars applies to the current unit.
 718    --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
 719
 720    Object_Directory_Present : Boolean := False;
 721    --  GNATMAKE
 722    --  Set to True when an object directory is specified with option -D
 723
 724    type Operating_Mode_Type is (Check_Syntax, Check_Semantics, Generate_Code);
 725    Operating_Mode : Operating_Mode_Type := Generate_Code;
 726    --  GNAT
 727    --  Indicates the operating mode of the compiler. The default is generate
 728    --  code, which runs the parser, semantics and backend. Switches can be
 729    --  used to set syntax checking only mode, or syntax and semantics checking
 730    --  only mode. Operating_Mode can also be modified as a result of detecting
 731    --  errors during the compilation process. In particular if any serious
 732    --  error is detected then this flag is reset from Generate_Code to
 733    --  Check_Semantics after generating an error message.
 734
 735    Original_Operating_Mode : Operating_Mode_Type := Generate_Code;
 736    --  GNAT
 737    --  Indicates the original operating mode of the compiler as set by
 738    --  compiler options. This is identical to Operating_Mode except that
 739    --  this is not affected by errors.
 740
 741    Optimization_Level : Int;
 742    pragma Import (C, Optimization_Level, "optimize");
 743    --  This constant reflects the optimization level (0,1,2 for -O0,-O1,-O2)
 744
 745    Output_File_Name_Present : Boolean := False;
 746    --  GNATBIND, GNAT, GNATMAKE
 747    --  Set to True when the output C file name is given with option -o
 748    --  for GNATBIND, when the object file name is given with option
 749    --  -gnatO for GNAT or when the executable is given with option -o
 750    --  for GNATMAKE.
 751
 752    Output_Linker_Option_List : Boolean := False;
 753    --  GNATBIND
 754    --  True if output of list of linker options is requested (-K switch set)
 755
 756    Output_Object_List : Boolean := False;
 757    --  GNATBIND
 758    --  True if output of list of objects is requested (-O switch set)
 759
 760    Pessimistic_Elab_Order : Boolean := False;
 761    --  GNATBIND
 762    --  True if pessimistic elaboration order is to be chosen (-p switch set)
 763
 764    Polling_Required : Boolean := False;
 765    --  GNAT
 766    --  Set to True if polling for asynchronous abort is enabled by using
 767    --  the -gnatP option for GNAT.
 768
 769    Preprocessing_Data_File : String_Ptr := null;
 770    --  GNAT
 771    --  Set by switch -gnatep=. The file name of the prepocessing data file.
 772
 773    Print_Generated_Code : Boolean := False;
 774    --  GNAT
 775    --  Set to True to enable output of generated code in source form. This
 776    --  flag is set by the -gnatG switch.
 777
 778    Print_Standard : Boolean := False;
 779    --  GNAT
 780    --  Set to true to enable printing of package standard in source form.
 781    --  This flag is set by the -gnatS switch
 782
 783    Propagate_Exceptions : Boolean := False;
 784    --  GNAT
 785    --  Indicates if subprogram descriptor exception tables should be
 786    --  built for imported subprograms. Set True if a Propagate_Exceptions
 787    --  pragma applies to the extended main unit.
 788
 789    type Usage is (Unknown, Not_In_Use, In_Use);
 790    Project_File_In_Use : Usage := Unknown;
 791    --  GNAT
 792    --  Indicates if a project file is used or not.
 793    --  Set to In_Use by the first SFNP pragma.
 794
 795    Queuing_Policy : Character := ' ';
 796    --  GNAT, GNATBIND
 797    --  Set to ' ' for the default case (no queuing policy specified).
 798    --  Reset to first character (uppercase) of locking policy name if a valid
 799    --  Queuing_Policy pragma is encountered.
 800
 801    Queuing_Policy_Sloc : Source_Ptr := No_Location;
 802    --  GNAT, GNATBIND
 803    --  Remember location of previous Queuing_Policy pragma. This is used
 804    --  for inconsistency error messages. A value of System_Location is
 805    --  used if the policy is set in package System.
 806
 807    Quiet_Output : Boolean := False;
 808    --  GNATMAKE, GNATCLEAN, GPR2MAKE
 809    --  Set to True if the tool should not have any output if there are no
 810    --  errors or warnings.
 811
 812    RTS_Lib_Path_Name : String_Ptr := null;
 813    RTS_Src_Path_Name : String_Ptr := null;
 814    --  GNAT
 815    --  Set to the "adalib" and "adainclude" directories of the run time
 816    --  specified by --RTS=.
 817
 818    RTS_Switch : Boolean := False;
 819    --  GNAT, GNATMAKE, GNATBIND, GNATLS, GNATFIND, GNATXREF
 820    --  Set to True when the --RTS switch is set
 821
 822    Run_Path_Option : Boolean := True;
 823    --  GNATMAKE, GNATLINK
 824    --  Set to False when no run_path_option should be issued to the linker
 825
 826    Sec_Stack_Used : Boolean := False;
 827    --  GNAT, GBATBIND
 828    --  Set True if generated code uses the System.Secondary_Stack package.
 829    --  For the binder, set if any unit uses the secondary stack package.
 830
 831    Shared_Libgnat : Boolean;
 832    --  GNATBIND
 833    --  Set to True if a shared libgnat is requested by using the -shared
 834    --  option for GNATBIND and to False when using the -static option. The
 835    --  value of this flag is set by Gnatbind.Scan_Bind_Arg.
 836
 837    Stack_Checking_Enabled : Boolean;
 838    --  GNAT
 839    --  Set to indicate if -fstack-check switch is set for the compilation.
 840    --  True means that the switch is set, so that stack checking is enabled.
 841    --  False means that the switch is not set (no stack checking). This
 842    --  value is obtained from the external imported value flag_stack_check
 843    --  in the gcc backend (see Frontend) and may be referenced throughout
 844    --  the compilation phases.
 845
 846    Style_Check : Boolean := False;
 847    --  GNAT
 848    --  Set True to perform style checks. Activates checks carried out
 849    --  in package Style (see body of this package for details of checks)
 850    --  This flag is set True by either the -gnatg or -gnaty switches.
 851
 852    System_Extend_Pragma_Arg : Node_Id := Empty;
 853    --  GNAT
 854    --  Set non-empty if and only if a correct Extend_System pragma was present
 855    --  in which case it points to the argument of the pragma, and the name can
 856    --  be located as Chars (Expression (System_Extend_Pragma_Arg)).
 857
 858    System_Extend_Unit : Node_Id := Empty;
 859    --  GNAT
 860    --  This is set to Empty if GNAT_Mode is set, since pragma Extend_System
 861    --  is never appropriate in GNAT_Mode (and causes troubles, including
 862    --  bogus circularities, if we try to compile the run-time library with
 863    --  a System extension). If GNAT_Mode is not set, then System_Extend_Unit
 864    --  is a copy of the value set in System_Extend_Pragma_Ary.
 865
 866    Subunits_Missing : Boolean := False;
 867    --  GNAT
 868    --  This flag is set true if missing subunits are detected with code
 869    --  generation active. This causes code generation to be skipped.
 870
 871    Suppress_Checks : Boolean := False;
 872    --  GNAT
 873    --  Set to True if -gnatp (suppress all checks) switch present.
 874
 875    Suppress_Options : Suppress_Array;
 876    --  GNAT
 877    --  Flags set True to suppress corresponding check, i.e. add an implicit
 878    --  pragma Suppress at the outer level of each unit compiled. Note that
 879    --  these suppress actions can be overridden by the use of the Unsuppress
 880    --  pragma. This variable is initialized by Osint.Initialize.
 881
 882    Suppress_Back_Annotation : Boolean := False;
 883    --  GNAT
 884    --  This flag is set True if back annotation of representation information
 885    --  is to be suppressed. This is set if neither -gnatt or -gnatR0-3 is set.
 886    --  This avoids unnecessary time being spent on back annotation.
 887
 888    Table_Factor : Int := 1;
 889    --  GNAT
 890    --  Factor by which all initial table sizes set in Alloc are multiplied.
 891    --  Used in Table to calculate initial table sizes (the initial table
 892    --  size is the value in Alloc, used as the Table_Initial parameter
 893    --  value, multiplied by the factor given here. The default value is
 894    --  used if no -gnatT switch appears.
 895
 896    Task_Dispatching_Policy : Character := ' ';
 897    --  GNAT, GNATBIND
 898    --  Set to ' ' for the default case (no task dispatching policy specified).
 899    --  Reset to first character (uppercase) of task dispatching policy name
 900    --  if a valid Task_Dispatching_Policy pragma is encountered.
 901
 902    Task_Dispatching_Policy_Sloc : Source_Ptr := No_Location;
 903    --  GNAT, GNATBIND
 904    --  Remember location of previous Task_Dispatching_Policy pragma. This is
 905    --  used for inconsistency error messages. A value of System_Location is
 906    --  used if the policy is set in package System.
 907
 908    Tasking_Used : Boolean := False;
 909    --  Set True if any tasking construct is encountered. Used to activate the
 910    --  output of the Q, L and T lines in ALI files.
 911
 912    Time_Slice_Set : Boolean := False;
 913    --  GNATBIND
 914    --  Set True if a pragma Time_Slice is processed in the main unit, or
 915    --  if the -gnatTnn switch is present to set a time slice value.
 916
 917    Time_Slice_Value : Nat;
 918    --  GNATBIND
 919    --  Time slice value. Valid only if Time_Slice_Set is True, i.e. if a
 920    --  Time_Slice pragma has been processed. Set to the time slice value
 921    --  in microseconds. Negative values are stored as zero, and the value
 922    --  is not larger than 1_000_000_000 (1000 seconds). Values larger than
 923    --  this are reset to this maximum. This can also be set with the -gnatTnn
 924    --  switch.
 925
 926    Tolerate_Consistency_Errors : Boolean := False;
 927    --  GNATBIND
 928    --  Tolerate time stamp and other consistency errors. If this flag is
 929    --  set to True (-t), then inconsistencies result in warnings rather than
 930    --  errors.
 931
 932    Tree_Output : Boolean := False;
 933    --  GNAT
 934    --  Set to True (-gnatt) to generate output tree file
 935
 936    Try_Semantics : Boolean := False;
 937    --  GNAT
 938    --  Flag set to force attempt at semantic analysis, even if parser errors
 939    --  occur. This will probably cause blowups at this stage in the game. On
 940    --  the other hand, most such blowups will be caught cleanly and simply
 941    --  say compilation abandoned. This flag is set to True by -gnatq or -gnatQ.
 942
 943    Undefined_Symbols_Are_False : Boolean := False;
 944    --  GNAT, GNATPREP
 945    --  Set to True by switch -u of gnatprep or -u in the preprocessing data
 946    --  file for the compiler. Indicates that while preprocessing sources,
 947    --  symbols that are not defined have the value FALSE.
 948
 949    Unique_Error_Tag : Boolean := Tag_Errors;
 950    --  GNAT
 951    --  Indicates if error messages are to be prefixed by the string error:
 952    --  Initialized from Tag_Errors, can be forced on with the -gnatU switch.
 953
 954    Universal_Addressing_On_AAMP : Boolean := False;
 955    --  GNAAMP
 956    --  Indicates if library-level objects should be accessed and updated
 957    --  using universal addressing instructions on the AAMP architecture.
 958    --  This flag is set to True when pragma Universal_Data is given as
 959    --  a configuration pragma.
 960
 961    Unreserve_All_Interrupts : Boolean := False;
 962    --  GNAT, GNATBIND
 963    --  Normally set False, set True if a valid Unreserve_All_Interrupts
 964    --  pragma appears anywhere in the main unit for GNAT, or if any ALI
 965    --  file has the corresponding attribute set in GNATBIND.
 966
 967    Upper_Half_Encoding : Boolean := False;
 968    --  GNAT
 969    --  Normally set False, indicating that upper half ASCII characters are
 970    --  used in the normal way to represent themselves. If the wide character
 971    --  encoding method uses the upper bit for this encoding, then this flag
 972    --  is set True, and upper half characters in the source indicate the
 973    --  start of a wide character sequence.
 974
 975    Usage_Requested : Boolean := False;
 976    --  GNAT, GNATBIND, GNATMAKE
 977    --  Set to True if -h (-gnath for the compiler) switch encountered
 978    --  requesting usage information
 979
 980    Use_VADS_Size : Boolean := False;
 981    --  GNAT
 982    --  Set to True if a valid pragma Use_VADS_Size is processed
 983
 984    Validity_Checks_On  : Boolean := True;
 985    --  GNAT
 986    --  This flag determines if validity checking is on or off. The initial
 987    --  state is on, and the required default validity checks are active. The
 988    --  actual set of checks that is performed if Validity_Checks_On is set
 989    --  is defined by the switches in package Sem_Val. The Validity_Checks_On
 990    --  flag is controlled by pragma Validity_Checks (On | Off), and also
 991    --  some generated compiler code (typically code that has to do with
 992    --  validity check generation) is compiled with this flag set to False.
 993    --  This flag is set to False by the -gnatp switch.
 994
 995    Verbose_Mode : Boolean := False;
 996    --  GNAT, GNATBIND, GNATMAKE, GNATLINK, GNATLS, GNATCHOP, GNATNAME,
 997    --  GNATCLEAN
 998    --  Set to True to get verbose mode (full error message text and location
 999    --  information sent to standard output, also header, copyright and summary)
1000
1001    Warn_On_Constant : Boolean := False;
1002    --  GNAT
1003    --  Set to True to generate warnings for variables that could be declared
1004    --  as constants. Modified by use of -gnatwk/K.
1005
1006    Warn_On_Dereference : Boolean := False;
1007    --  GNAT
1008    --  Set to True to generate warnings for implicit dereferences for array
1009    --  indexing and record component access. Modified by use of -gnatwd/D.
1010
1011    Warn_On_Export_Import : Boolean := True;
1012    --  GNAT
1013    --  Set to True to generate warnings for suspicious use of export or
1014    --  import pragmas. Modified by use of -gnatwx/X.
1015
1016    Warn_On_Hiding : Boolean := False;
1017    --  GNAT
1018    --  Set to True to generate warnings if a declared entity hides another
1019    --  entity. The default is that this warning is suppressed.
1020
1021    Warn_On_Modified_Unread : Boolean := False;
1022    --  GNAT
1023    --  Set to True to generate warnings if a variable is assigned but is
1024    --  never read. The default is that this warning is suppressed.
1025
1026    Warn_On_No_Value_Assigned : Boolean := True;
1027    --  GNAT
1028    --  Set to True to generate warnings if no value is ever assigned to a
1029    --  variable that is at least partially uninitialized. Set to false to
1030    --  suppress such warnings. The default is that such warnings are enabled.
1031
1032    Warn_On_Obsolescent_Feature : Boolean := False;
1033    --  GNAT
1034    --  Set to True to generate warnings on use of any feature in Annex J
1035    --  or if a subprogram is called for which a pragma Obsolescent applies.
1036
1037    Warn_On_Redundant_Constructs : Boolean := False;
1038    --  GNAT
1039    --  Set to True to generate warnings for redundant constructs (e.g. useless
1040    --  assignments/conversions). The default is that this warning is disabled.
1041
1042    Warn_On_Unchecked_Conversion : Boolean := True;
1043    --  GNAT
1044    --  Set to True to generate warnings for unchecked conversions that may have
1045    --  non-portable semantics (e.g. because sizes of types differ). The default
1046    --  is that this warning is enabled.
1047
1048    Warn_On_Unrecognized_Pragma : Boolean := True;
1049    --  GNAT
1050    --  Set to True to generate warnings for unrecognized pragmas. The default
1051    --  is that this warning is enabled.
1052
1053    type Warning_Mode_Type is (Suppress, Normal, Treat_As_Error);
1054    Warning_Mode : Warning_Mode_Type := Normal;
1055    --  GNAT, GNATBIND
1056    --  Controls treatment of warning messages. If set to Suppress, warning
1057    --  messages are not generated at all. In Normal mode, they are generated
1058    --  but do not count as errors. In Treat_As_Error mode, warning messages
1059    --  are generated and are treated as errors.
1060
1061    Wide_Character_Encoding_Method : WC_Encoding_Method := WCEM_Brackets;
1062    --  GNAT
1063    --  Method used for encoding wide characters in the source program. See
1064    --  description of type in unit System.WCh_Con for a list of the methods
1065    --  that are currently supported. Note that brackets notation is always
1066    --  recognized in source programs regardless of the setting of this
1067    --  variable. The default setting causes only the brackets notation
1068    --  to be recognized. If this is the main unit, this setting also
1069    --  controls the output of the W=? parameter in the ALI file, which
1070    --  is used to provide the default for Wide_Text_IO files.
1071
1072    Xref_Active : Boolean := True;
1073    --  GNAT
1074    --  Set if cross-referencing is enabled (i.e. xref info in ALI files)
1075
1076    Zero_Cost_Exceptions_Val : Boolean;
1077    Zero_Cost_Exceptions_Set : Boolean := False;
1078    --  GNAT
1079    --  These values are to record the setting of the zero cost exception
1080    --  handling mode set by argument switches (-gnatZ/-gnatL). If the
1081    --  value is set by one of these switches, then Zero_Cost_Exceptions_Set
1082    --  is set to True, and Zero_Cost_Exceptions_Val indicates the setting.
1083
1084    ----------------------------
1085    -- Configuration Settings --
1086    ----------------------------
1087
1088    --  These are settings that are used to establish the mode at the start
1089    --  of each unit. The values defined below can be affected either by
1090    --  command line switches, or by the use of appropriate configuration
1091    --  pragmas in the gnat.adc file.
1092
1093    Ada_83_Config : Boolean;
1094    --  GNAT
1095    --  This is the value of the configuration switch for Ada 83 mode, as set
1096    --  by the command line switch -gnat83, and possibly modified by the use
1097    --  of configuration pragmas Ada_95 and Ada_83 in the gnat.adc file. This
1098    --  switch is used to set the initial value for Ada_83 mode at the start
1099    --  of analysis of a unit. Note however, that the setting of this flag
1100    --  is ignored for internal and predefined units (which are always compiled
1101    --  in Ada 95 mode).
1102
1103    Dynamic_Elaboration_Checks_Config : Boolean := False;
1104    --  GNAT
1105    --  Set True for dynamic elaboration checking mode, as set by the -gnatE
1106    --  switch or by the use of pragma Elaboration_Checking (Dynamic).
1107
1108    Exception_Locations_Suppressed_Config : Boolean := False;
1109    --  GNAT
1110    --  Set True by use of the configuration pragma Suppress_Exception_Messages
1111
1112    Extensions_Allowed_Config : Boolean;
1113    --  GNAT
1114    --  This is the flag that indicates whether extensions are allowed.
1115    --  It can be set True either by use of the -gnatX switch, or by use
1116    --  of the configuration pragma Extensions_Allowed (On). It is always
1117    --  set to True for internal GNAT units, since extensions are always
1118    --  permitted in such units.
1119
1120    External_Name_Exp_Casing_Config : External_Casing_Type;
1121    --  GNAT
1122    --  This is the value of the configuration switch that controls casing
1123    --  of external symbols for which an explicit external name is given. It
1124    --  can be set to Uppercase by the command line switch -gnatF, and further
1125    --  modified by the use of the configuration pragma External_Name_Casing
1126    --  in the gnat.adc file. This flag is used to set the initial value
1127    --  for External_Name_Exp_Casing at the start of analyzing each unit.
1128    --  Note however that the setting of this flag is ignored for internal
1129    --  and predefined units (which are always compiled with As_Is mode).
1130
1131    External_Name_Imp_Casing_Config : External_Casing_Type;
1132    --  GNAT
1133    --  This is the value of the configuration switch that controls casing
1134    --  of external symbols where the external name is implicitly given. It
1135    --  can be set to Uppercase by the command line switch -gnatF, and further
1136    --  modified by the use of the configuration pragma External_Name_Casing
1137    --  in the gnat.adc file. This flag is used to set the initial value
1138    --  for External_Name_Imp_Casing at the start of analyzing each unit.
1139    --  Note however that the setting of this flag is ignored for internal
1140    --  and predefined units (which are always compiled with Lowercase mode).
1141
1142    Polling_Required_Config : Boolean;
1143    --  GNAT
1144    --  This is the value of the configuration switch that controls polling
1145    --  mode. It can be set True by the command line switch -gnatP, and then
1146    --  further modified by the use of pragma Polling in the gnat.adc file.
1147    --  This flag is used to set the initial value for Polling_Required
1148    --  at the start of analyzing each unit.
1149
1150    Use_VADS_Size_Config : Boolean;
1151    --  GNAT
1152    --  This is the value of the configuration switch that controls the use
1153    --  of VADS_Size instead of Size whereever the attribute Size is used.
1154    --  It can be set True by the use of the pragma Use_VADS_Size in the
1155    --  gnat.adc file. This flag is used to set the initial value for
1156    --  Use_VADS_Size at the start of analyzing each unit. Note however that
1157    --  the setting of this flag is ignored for internal and predefined
1158    --  units (which are always compiled with the standard Size semantics).
1159
1160    type Config_Switches_Type is private;
1161    --  Type used to save values of the switches set from Config values
1162
1163    procedure Save_Opt_Config_Switches (Save : out Config_Switches_Type);
1164    --  This procedure saves the current values of the switches which are
1165    --  initialized from the above Config values, and then resets these
1166    --  switches according to the Config value settings.
1167
1168    procedure Set_Opt_Config_Switches (Internal_Unit : Boolean);
1169    --  This procedure sets the switches to the appropriate initial values.
1170    --  The parameter Internal_Unit is True for an internal or predefined
1171    --  unit, and affects the way the switches are set (see above).
1172
1173    procedure Restore_Opt_Config_Switches (Save : Config_Switches_Type);
1174    --  This procedure restores a set of switch values previously saved
1175    --  by a call to Save_Opt_Switches.
1176
1177    procedure Register_Opt_Config_Switches;
1178    --  This procedure is called after processing the gnat.adc file to record
1179    --  the values of the Config switches, as possibly modified by the use
1180    --  of command line switches and configuration pragmas.
1181
1182    ------------------------
1183    -- Other Global Flags --
1184    ------------------------
1185
1186    Expander_Active : Boolean := False;
1187    --  A flag that indicates if expansion is active (True) or deactivated
1188    --  (False). When expansion is deactivated all calls to expander routines
1189    --  have no effect. Note that the initial setting of False is merely to
1190    --  prevent saving of an undefined value for an initial call to the
1191    --  Expander_Mode_Save_And_Set procedure. For more information on the
1192    --  use of this flag, see package Expander. Indeed this flag might more
1193    --  logically be in the spec of Expander, but it is referenced by Errout,
1194    --  and it really seems wrong for Errout to depend on Expander.
1195
1196    -----------------------
1197    -- Tree I/O Routines --
1198    -----------------------
1199
1200    procedure Tree_Read;
1201    --  Reads switch settings from current tree file using Tree_Read
1202
1203    procedure Tree_Write;
1204    --  Writes out switch settings to current tree file using Tree_Write
1205
1206    --------------------------
1207    -- ASIS Version Control --
1208    --------------------------
1209
1210    --  These two variables (Tree_Version_String and Tree_ASIS_Version_Number)
1211    --  are supposed to be used in the GNAT/ASIS version check performed in
1212    --  the ASIS code (this package is also a part of the ASIS implementation).
1213    --  They are set by Tree_Read procedure, so they represent the version
1214    --  number (and the version string) of the compiler which has created the
1215    --  tree, and they are supposed to be compared with the corresponding values
1216    --  from the Gnatvsn package which is a part of ASIS implementation.
1217
1218    Tree_Version_String : String (Gnat_Version_String'Range);
1219    --  Used to store the compiler version string read from a tree file to
1220    --  check if it is the same as stored in the version string in Gnatvsn.
1221    --  Therefore its length is taken directly from the version string in
1222    --  Gnatvsn. If the length of the version string stored in the tree is
1223    --  different, then versions are for sure different, and a string containing
1224    --  '?' characters is assigned to this variable as a result of tree read.
1225
1226    Tree_ASIS_Version_Number : Int;
1227    --  Used to store the ASIS version number read from a tree file to check if
1228    --  it is the same as stored in the ASIS version number in Gnatvsn.
1229
1230 private
1231
1232    type Config_Switches_Type is record
1233       Ada_83                         : Boolean;
1234       Dynamic_Elaboration_Checks     : Boolean;
1235       Exception_Locations_Suppressed : Boolean;
1236       Extensions_Allowed             : Boolean;
1237       External_Name_Exp_Casing       : External_Casing_Type;
1238       External_Name_Imp_Casing       : External_Casing_Type;
1239       Polling_Required               : Boolean;
1240       Use_VADS_Size                  : Boolean;
1241    end record;
1242
1243 end Opt;