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) 1992-2006, 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,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, 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 routine from
  35 --  the command line and referenced throughout the compiler, the binder, or
  36 --  other GNAT tools. The comments indicate which options are used by which
  37 --  programs (GNAT, GNATBIND, GNATLINK, GNATMAKE, GPRMAKE, etc).
  38
  39 with Hostparm; use Hostparm;
  40 with Types;    use Types;
  41
  42 with System.WCh_Con; use System.WCh_Con;
  43 with GNAT.Strings;   use GNAT.Strings;
  44
  45 package Opt is
  46
  47    ----------------------------------------------
  48    -- Settings of Modes for Current Processing --
  49    ----------------------------------------------
  50
  51    --  The following mode values represent the current state of processing.
  52    --  The values set here are the default values. Unless otherwise noted,
  53    --  the value may be reset in Switch-? with an appropropiate switch. In
  54    --  some cases, the values can also be modified by pragmas, and in the
  55    --  case of some binder variables, Gnatbind.Scan_Bind_Arg may modify
  56    --  the default values.
  57
  58    Ada_Bind_File : Boolean := True;
  59    --  GNATBIND, GNATLINK
  60    --  Set True if binder file to be generated in Ada rather than C
  61
  62    type Ada_Version_Type is (Ada_83, Ada_95, Ada_05);
  63    pragma Warnings (Off, Ada_Version_Type);
  64    --  Versions of Ada for Ada_Version below. Note that these are ordered,
  65    --  so that tests like Ada_Version >= Ada_95 are legitimate and useful.
  66    --  The Warnings_Off pragma stops warnings for Ada_Version >= Ada_05,
  67    --  which we want to allow, so that things work OK when Ada_15 is added!
  68    --  This warning is now removed, so this pragma can be removed some time???
  69
  70    Ada_Version_Default : Ada_Version_Type := Ada_05;
  71    --  GNAT
  72    --  Default Ada version if no switch given
  73
  74    Ada_Version : Ada_Version_Type := Ada_Version_Default;
  75    --  GNAT
  76    --  Current Ada version for compiler, as set by configuration pragmas,
  77    --  compiler switches, or implicitly (to Ada_Version_Runtime) when a
  78    --  predefined or internal file is compiled.
  79
  80    Ada_Version_Explicit : Ada_Version_Type := Ada_Version_Default;
  81    --  GNAT
  82    --  Like Ada_Version, but does not get set implicitly for predefined
  83    --  or internal units, so it reflects the Ada version explicitly set
  84    --  using configuration pragmas or compiler switches (or if neither
  85    --  appears, it remains set to Ada_Version_Default). This is used in
  86    --  the rare cases (notably for pragmas Preelaborate_05 and Pure_05)
  87    --  where in the run-time we want the explicit version set.
  88
  89    Ada_Version_Runtime : Ada_Version_Type := Ada_05;
  90    --  GNAT
  91    --  Ada version used to compile the runtime. Used to set Ada_Version (but
  92    --  not Ada_Version_Explicit) when compiling predefined or internal units.
  93
  94    Ada_Final_Suffix : constant String := "final";
  95    Ada_Final_Name   : String_Ptr := new String'("ada" & Ada_Final_Suffix);
  96    --  GNATBIND
  97    --  The name of the procedure that performs the finalization at the end of
  98    --  execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
  99
 100    Ada_Init_Suffix : constant String := "init";
 101    Ada_Init_Name   : String_Ptr := new String'("ada" & Ada_Init_Suffix);
 102    --  GNATBIND
 103    --  The name of the procedure that performs initialization at the start
 104    --  of execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
 105
 106    Ada_Main_Name_Suffix : constant String := "main";
 107    --  GNATBIND
 108    --  The suffix for Ada_Main_Name. Defined as a constant here so that it
 109    --  can be referenced in a uniform manner to create either the default
 110    --  value of Ada_Main_Name (declared below), or the non-default name
 111    --  set by Gnatbind.Scan_Bind_Arg.
 112
 113    Ada_Main_Name : String_Ptr := new String'("ada_" & Ada_Main_Name_Suffix);
 114    --  GNATBIND
 115    --  The name of the Ada package generated by the binder (when in Ada mode).
 116    --  This variable may be modified by Gnatbind.Scan_Bind_Arg.
 117
 118    Address_Clause_Overlay_Warnings : Boolean := True;
 119    --  GNAT
 120    --  Set False to disable address clause warnings
 121
 122    Address_Is_Private : Boolean := False;
 123    --  GNAT, GNATBIND
 124    --  Set True if package System has the line "type Address is private;"
 125
 126    All_Errors_Mode : Boolean := False;
 127    --  GNAT
 128    --  Flag set to force display of multiple errors on a single line and
 129    --  also repeated error messages for references to undefined identifiers
 130    --  and certain other repeated error messages. Set by use of -gnatf.
 131
 132    All_Sources : Boolean := False;
 133    --  GNATBIND
 134    --  Set to True to require all source files to be present. This flag is
 135    --  directly modified by gnatmake to affect the shared binder routines.
 136
 137    Alternate_Main_Name : String_Ptr := null;
 138    --  GNATBIND
 139    --  Set to non null when Bind_Alternate_Main_Name is True. This value
 140    --  is modified as needed by Gnatbind.Scan_Bind_Arg.
 141
 142    Assertions_Enabled : Boolean := False;
 143    --  GNAT
 144    --  Enable assertions made using pragma Assert
 145
 146    ASIS_Mode : Boolean := False;
 147    --  GNAT
 148    --  Enable semantic checks and tree transformations that are important
 149    --  for ASIS but that are usually skipped if Operating_Mode is set to
 150    --  Check_Semantics. This flag does not have the corresponding option to set
 151    --  it ON. It is set ON when Tree_Output is set ON, it can also be set ON
 152    --  from the code of GNSA-based tool (a client may need to set ON the
 153    --  Back_Annotate_Rep_Info flag in this case. At the moment this does not
 154    --  make very much sense, because GNSA cannot do back annotation).
 155
 156    Back_Annotate_Rep_Info : Boolean := False;
 157    --  GNAT
 158    --  If set True, enables back annotation of representation information
 159    --  by gigi, even in -gnatc mode. This is set True by the use of -gnatR
 160    --  (list representation information) or -gnatt (generate tree). It is
 161    --  also set true if certain Unchecked_Conversion instantiations require
 162    --  checking based on annotated values.
 163
 164    Bind_Alternate_Main_Name : Boolean := False;
 165    --  GNATBIND
 166    --  True if main should be called Alternate_Main_Name.all.
 167    --  This variable may be set to True by Gnatbind.Scan_Bind_Arg.
 168
 169    Bind_Main_Program : Boolean := True;
 170    --  GNATBIND
 171    --  Set to False if not binding main Ada program
 172
 173    Bind_For_Library : Boolean := False;
 174    --  GNATBIND
 175    --  Set to True if the binder needs to generate a file designed for
 176    --  building a library. May be set to True by Gnatbind.Scan_Bind_Arg.
 177
 178    Bind_Only : Boolean := False;
 179    --  GNATMAKE, GPRMAKE
 180    --  Set to True to skip compile and link steps
 181    --  (except when Compile_Only and/or Link_Only are True).
 182
 183    Blank_Deleted_Lines : Boolean := False;
 184    --  GNAT, GNATPREP
 185    --  Output empty lines for each line of preprocessed input that is deleted
 186    --  in the output, including preprocessor lines starting with a '#'.
 187
 188    Brief_Output : Boolean := False;
 189    --  GNAT, GNATBIND
 190    --  Force brief error messages to standard error, even if verbose mode is
 191    --  set (so that main error messages go to standard output).
 192
 193    Build_Bind_And_Link_Full_Project : Boolean := False;
 194    --  GNATMAKE
 195    --  Set to True to build, bind and link all the sources of a project file
 196    --  (switch -B)
 197
 198    Check_Object_Consistency : Boolean := False;
 199    --  GNATBIND, GNATMAKE
 200    --  Set to True to check whether every object file is consistent with
 201    --  its corresponding ada library information (ALI) file. An object
 202    --  file is inconsistent with the corresponding ALI file if the object
 203    --  file does not exist or if it has an older time stamp than the ALI file.
 204    --  Default above is for GNATBIND. GNATMAKE overrides this default to
 205    --  True (see Make.Initialize) since we normally do need to check source
 206    --  consistencies in gnatmake.
 207
 208    Check_Only : Boolean := False;
 209    --  GNATBIND
 210    --  Set to True to do checks only, no output of binder file
 211
 212    Check_Readonly_Files : Boolean := False;
 213    --  GNATMAKE
 214    --  Set to True to check readonly files during the make process
 215
 216    Check_Source_Files : Boolean := True;
 217    --  GNATBIND, GNATMAKE
 218    --  Set to True to enable consistency checking for any source files that
 219    --  are present (i.e. date must match the date in the library info file).
 220    --  Set to False for object file consistency check only. This flag is
 221    --  directly modified by gnatmake, to affect the shared binder routines.
 222
 223    Check_Switches : Boolean := False;
 224    --  GNATMAKE, GPRMAKE
 225    --  Set to True to check compiler options during the make process
 226
 227    Check_Unreferenced : Boolean := False;
 228    --  GNAT
 229    --  Set to True to enable checking for unreferenced entities other
 230    --  than formal parameters (for which see Check_Unreferenced_Formals)
 231
 232    Check_Unreferenced_Formals : Boolean := False;
 233    --  GNAT
 234    --  Set True to check for unreferenced formals. This is turned on by
 235    --  -gnatwa/wf/wu and turned off by -gnatwA/wF/wU.
 236
 237    Check_Withs : Boolean := False;
 238    --  GNAT
 239    --  Set to True to enable checking for unused withs, and also the case
 240    --  of withing a package and using none of the entities in the package.
 241
 242    Commands_To_Stdout : Boolean := False;
 243    --  GNATMAKE
 244    --  True if echoed commands to be written to stdout instead of stderr
 245
 246    Comment_Deleted_Lines : Boolean := False;
 247    --  GNATPREP
 248    --  True if source lines removed by the preprocessor should be commented
 249    --  in the output file.
 250
 251    Compile_Only : Boolean := False;
 252    --  GNATMAKE, GNATCLEAN, GPRMAKE
 253    --  GNATMAKE, GPRMAKE: set to True to skip bind and link steps (except when
 254    --                     Bind_Only is True).
 255    --  GNATCLEAN: set to True to only the files produced by the compiler are to
 256    --             be deleted, but not the library files or executable files.
 257
 258    Config_File : Boolean := True;
 259    --  GNAT
 260    --  Set to False to inhibit reading and processing of gnat.adc file
 261
 262    Config_File_Names : String_List_Access := null;
 263    --  GNAT
 264    --  Names of configuration pragmas files (given by switches -gnatec)
 265
 266    Configurable_Run_Time_Mode : Boolean := False;
 267    --  GNAT, GNATBIND
 268    --  Set True if the compiler is operating in configurable run-time mode.
 269    --  This happens if the flag Targparm.Configurable_Run_TimeMode_On_Target
 270    --  is set True, or if pragma No_Run_Time is used. See the spec of Rtsfind
 271    --  for details on the handling of the latter pragma.
 272
 273    Constant_Condition_Warnings : Boolean := False;
 274    --  GNAT
 275    --  Set to True to activate warnings on constant conditions
 276
 277    Create_Mapping_File : Boolean := False;
 278    --  GNATMAKE, GPRMAKE
 279    --  Set to True (-C switch) to indicate that the compiler will be invoked
 280    --  with a mapping file (-gnatem compiler switch).
 281
 282    Debug_Pragmas_Enabled : Boolean := False;
 283    --  GNAT
 284    --  Enable debug statements from pragma Debug
 285
 286    subtype Debug_Level_Value is Nat range 0 .. 3;
 287    Debugger_Level : Debug_Level_Value := 0;
 288    --  GNATBIND
 289    --  The value given to the -g parameter. The default value for -g with
 290    --  no value is 2. This is usually ignored by GNATBIND, except in the
 291    --  VMS version where it is passed as an argument to __gnat_initialize
 292    --  to trigger the activation of the remote debugging interface.
 293    --  Is this still true ???
 294
 295    Debug_Generated_Code : Boolean := False;
 296    --  GNAT
 297    --  Set True (-gnatD switch) to debug generated expanded code instead
 298    --  of the original source code. Causes debugging information to be
 299    --  written with respect to the generated code file that is written.
 300
 301    Default_Exit_Status : Int := 0;
 302    --  GNATBIND
 303    --  Set the default exit status value. Set by the -Xnnn switch for the
 304    --  binder.
 305
 306    Default_Stack_Size : Int := -1;
 307    --  GNATBIND
 308    --  Set to default primary stack size in units of bytes. Set by
 309    --  the -dnnn switch for the binder. A value of -1 indicates that no
 310    --  default was set by the binder.
 311
 312    Default_Sec_Stack_Size : Int := -1;
 313    --  GNATBIND
 314    --  Set to default secondary stack size in units of bytes. Set by
 315    --  the -Dnnn switch for the binder. A value of -1 indicates that no
 316    --  default was set by the binder, and that the default should be the
 317    --  initial value of System.Secondary_Stack.Default_Secondary_Stack_Size.
 318
 319    Detect_Blocking : Boolean := False;
 320    --  GNAT
 321    --  Set True to force the run time to raise Program_Error if calls to
 322    --  potentially blocking operations are detected from protected actions.
 323
 324    Display_Compilation_Progress : Boolean := False;
 325    --  GNATMAKE, GPRMAKE
 326    --  Set True (-d switch) to display information on progress while compiling
 327    --  files. Internal flag to be used in conjunction with an IDE (e.g GPS).
 328
 329    type Distribution_Stub_Mode_Type is
 330    --  GNAT
 331      (No_Stubs,
 332       --  Normal mode, no generation/compilation of distribution stubs
 333
 334       Generate_Receiver_Stub_Body,
 335       --  The unit being compiled is the RCI body, and the compiler will
 336       --  generate the body for the receiver stubs and compile it.
 337
 338       Generate_Caller_Stub_Body);
 339       --  The unit being compiled is the RCI spec, and the compiler will
 340       --  generate the body for the caller stubs and compile it.
 341
 342    Distribution_Stub_Mode : Distribution_Stub_Mode_Type := No_Stubs;
 343    --  GNAT
 344    --  This enumeration variable indicates the five states of distribution
 345    --  annex stub generation/compilation.
 346
 347    Do_Not_Execute : Boolean := False;
 348    --  GNATMAKE
 349    --  Set to True if no actual compilations should be undertaken.
 350
 351    Dump_Source_Text : Boolean := False;
 352    --  GNAT
 353    --  Set to True (by -gnatL) to dump source text intermingled with generated
 354    --  code. Effective only if either of Debug/Print_Generated_Code is true.
 355
 356    Dynamic_Elaboration_Checks : Boolean := False;
 357    --  GNAT
 358    --  Set True for dynamic elaboration checking mode, as set by the -gnatE
 359    --  switch or by the use of pragma Elaboration_Checks (Dynamic).
 360
 361    Dynamic_Stack_Measurement : Boolean := False;
 362    --  GNATBIND
 363    --  Set True to enable dynamic stack measurement (-u flag for gnatbind)
 364
 365    Dynamic_Stack_Measurement_Array_Size : Nat := 100;
 366    --  GNATBIND
 367    --  Number of measurements we want to store during dynamic stack analysis.
 368    --  When the buffer is full, non-storable results will be output on the fly.
 369    --  The value is relevant only if Dynamic_Stack_Measurement is set. Set
 370    --  by processing of -u flag for gnatbind.
 371
 372    Elab_Dependency_Output : Boolean := False;
 373    --  GNATBIND
 374    --  Set to True to output complete list of elaboration constraints
 375
 376    Elab_Order_Output : Boolean := False;
 377    --  GNATBIND
 378    --  Set to True to output chosen elaboration order
 379
 380    Elab_Warnings : Boolean := False;
 381    --  GNAT
 382    --  Set to True to generate full elaboration warnings (-gnatwl)
 383
 384    Enable_Overflow_Checks : Boolean := False;
 385    --  GNAT
 386    --  Set to True if -gnato (enable overflow checks) switch is set,
 387    --  but not -gnatp.
 388
 389    Error_Msg_Line_Length : Nat := 0;
 390    --  GNAT
 391    --  Records the error message line length limit. If this is set to zero,
 392    --  then we get the old style behavior, in which each call to the error
 393    --  message routines generates one line of output as a separate message.
 394    --  If it is set to a non-zero value, then continuation lines are folded
 395    --  to make a single long message, and then this message is split up into
 396    --  multiple lines not exceeding the specified length. Set by -gnatLnnn.
 397
 398    Exception_Locations_Suppressed : Boolean := False;
 399    --  GNAT
 400    --  This flag is set True if a Suppress_Exception_Locations configuration
 401    --  pragma is currently active.
 402
 403    type Exception_Mechanism_Type is
 404    --  Determines the handling of exceptions. See Exp_Ch11 for details
 405    --
 406      (Front_End_Setjmp_Longjmp_Exceptions,
 407       --  Exceptions use setjmp/longjmp generated explicitly by the
 408       --  front end (this includes gigi or other equivalent parts of
 409       --  the code generator). AT END handlers are converted into
 410       --  exception handlers by the front end in this mode.
 411
 412       Back_End_Exceptions);
 413       --  Exceptions are handled by the back end. The front end simply
 414       --  generates the handlers as they appear in the source, and AT
 415       --  END handlers are left untouched (they are not converted into
 416       --  exception handlers when operating in this mode.
 417    pragma Convention (C, Exception_Mechanism_Type);
 418
 419    Exception_Mechanism : Exception_Mechanism_Type :=
 420                            Front_End_Setjmp_Longjmp_Exceptions;
 421    --  GNAT
 422    --  Set to the appropriate value depending on the default as given in
 423    --  system.ads (ZCX_By_Default, GCC_ZCX_Support).
 424    --  The C convention is there to make this variable accessible to gigi.
 425
 426    Exception_Tracebacks : Boolean := False;
 427    --  GNATBIND
 428    --  Set to True to store tracebacks in exception occurrences (-E)
 429
 430    Extensions_Allowed : Boolean := False;
 431    --  GNAT
 432    --  Set to True by switch -gnatX if GNAT specific language extensions
 433    --  are allowed. For example, "limited with" is a GNAT extension.
 434
 435    type External_Casing_Type is (
 436      As_Is,       -- External names cased as they appear in the Ada source
 437      Uppercase,   -- External names forced to all uppercase letters
 438      Lowercase);  -- External names forced to all lowercase letters
 439
 440    External_Name_Imp_Casing : External_Casing_Type := Lowercase;
 441    --  GNAT
 442    --  The setting of this flag determines the casing of external names
 443    --  when the name is implicitly derived from an entity name (i.e. either
 444    --  no explicit External_Name or Link_Name argument is used, or, in the
 445    --  case of extended DEC pragmas, the external name is given using an
 446    --  identifier. The As_Is setting is not permitted here (since this would
 447    --  create Ada source programs that were case sensitive).
 448
 449    External_Name_Exp_Casing : External_Casing_Type := As_Is;
 450    --  GNAT
 451    --  The setting of this flag determines the casing of an external name
 452    --  specified explicitly with a string literal. As_Is means the string
 453    --  literal is used as given with no modification to the casing. If
 454    --  Lowercase or Uppercase is set, then the string is forced to all
 455    --  lowercase or all uppercase letters as appropriate. Note that this
 456    --  setting has no effect if the external name is given using an identifier
 457    --  in the case of extended DEC import/export pragmas (in this case the
 458    --  casing is controlled by External_Name_Imp_Casing), and also has no
 459    --  effect if an explicit Link_Name is supplied (a link name is always
 460    --  used exactly as given).
 461
 462    External_Unit_Compilation_Allowed : Boolean := False;
 463    --  GNATMAKE
 464    --  When True (set by gnatmake switch -x), allow compilation of sources
 465    --  that are not part of any project file.
 466
 467    Float_Format : Character := ' ';
 468    --  GNAT
 469    --  A non-blank value indicates that a Float_Format pragma has been
 470    --  processed, in which case this variable is set to 'I' for IEEE or
 471    --  to 'V' for VAX. The setting of 'V' is only possible on OpenVMS
 472    --  versions of GNAT.
 473
 474    Float_Format_Long : Character := ' ';
 475    --  GNAT
 476    --  A non-blank value indicates that a Long_Float pragma has been
 477    --  processed (this pragma is recognized only in OpenVMS versions
 478    --  of GNAT), in which case this variable is set to D or G for
 479    --  D_Float or G_Float.
 480
 481    Force_ALI_Tree_File : Boolean := False;
 482    --  GNAT
 483    --  Force generation of ALI file even if errors are encountered.
 484    --  Also forces generation of tree file if -gnatt is also set.
 485
 486    Force_Checking_Of_Elaboration_Flags : Boolean := False;
 487    --  GNATBIND
 488    --  True if binding with forced checking of the elaboration flags
 489    --  (-F switch set).
 490
 491    Force_Compilations : Boolean := False;
 492    --  GNATMAKE, GPRMAKE
 493    --  Set to force recompilations even when the objects are up-to-date.
 494
 495    Full_Path_Name_For_Brief_Errors : Boolean := False;
 496    --  GNAT, GNATMAKE, GNATCLEAN, GPRMAKE
 497    --  When True, in Brief_Output mode, each error message line
 498    --  will start with the full path name of the source.
 499    --  When False, only the file name without directory information
 500    --  is used.
 501
 502    Full_List : Boolean := False;
 503    --  GNAT
 504    --  Set True to generate full source listing with embedded errors
 505
 506    Full_List_File_Name : String_Ptr := null;
 507    --  GNAT
 508    --  Set to file name to generate full source listing to named file (or if
 509    --  the name is of the form .xxx, then to name.xxx where name is the source
 510    --  file name with extension stripped.
 511
 512    function get_gcc_version return Int;
 513    pragma Import (C, get_gcc_version, "get_gcc_version");
 514
 515    GCC_Version : constant Nat := get_gcc_version;
 516    --  GNATMAKE
 517    --  Indicates which version of gcc is in use (2 = 2.8.1, 3 = 3.x)
 518
 519    Global_Discard_Names : Boolean := False;
 520    --  GNAT, GNATBIND
 521    --  Set true if a pragma Discard_Names applies to the current unit
 522
 523    GNAT_Mode : Boolean := False;
 524    --  GNAT
 525    --  True if compiling in GNAT system mode (-gnatg switch)
 526
 527    HLO_Active : Boolean := False;
 528    --  GNAT
 529    --  True if High Level Optimizer is activated (-gnatH switch)
 530
 531    Implementation_Unit_Warnings : Boolean := True;
 532    --  GNAT
 533    --  Set True to active warnings for use of implementation internal units.
 534    --  Can be controlled by use of -gnatwi/-gnatwI.
 535
 536    Identifier_Character_Set : Character;
 537    --  GNAT
 538    --  This variable indicates the character set to be used for identifiers.
 539    --  The possible settings are:
 540    --    '1'  Latin-5 (ISO-8859-1)
 541    --    '2'  Latin-5 (ISO-8859-2)
 542    --    '3'  Latin-5 (ISO-8859-3)
 543    --    '4'  Latin-5 (ISO-8859-4)
 544    --    '5'  Latin-5 (ISO-8859-5, Cyrillic)
 545    --    '9'  Latin-5 (ISO-8859-9)
 546    --    'p'  PC (US, IBM page 437)
 547    --    '8'  PC (European, IBM page 850)
 548    --    'f'  Full upper set (all distinct)
 549    --    'n'  No upper characters (Ada 83 rules)
 550    --    'w'  Latin-1 plus wide characters allowed in identifiers
 551    --
 552    --  The setting affects the set of letters allowed in identifiers and the
 553    --  upper/lower case equivalences. It does not affect the interpretation of
 554    --  character and string literals, which are always stored using the actual
 555    --  coding in the source program. This variable is initialized to the
 556    --  default value appropriate to the system (in Osint.Initialize), and then
 557    --  reset if a command line switch is used to change the setting.
 558
 559    Ineffective_Inline_Warnings : Boolean := False;
 560    --  GNAT
 561    --  Set True to activate warnings if front-end inlining (-gnatN) is not
 562    --  able to actually inline a particular call (or all calls). Can be
 563    --  controlled by use of -gnatwp/-gnatwP.
 564
 565    Init_Or_Norm_Scalars : Boolean := False;
 566    --  GNAT, GANTBIND
 567    --  Set True if a pragma Initialize_Scalars applies to the current unit.
 568    --  Also set True if a pragma Normalize_Scalars applies.
 569
 570    Initialize_Scalars : Boolean := False;
 571    --  GNAT
 572    --  Set True if a pragma Initialize_Scalars applies to the current unit.
 573    --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
 574
 575    Initialize_Scalars_Mode1 : Character := 'I';
 576    Initialize_Scalars_Mode2 : Character := 'N';
 577    --  GNATBIND
 578    --  Set to two characters from -S switch (IN/LO/HI/EV/xx). The default
 579    --  is IN (invalid values), used if no -S switch is used.
 580
 581    Inline_Active : Boolean := False;
 582    --  GNAT
 583    --  Set True to activate pragma Inline processing across modules. Default
 584    --  for now is not to inline across module boundaries.
 585
 586    Interface_Library_Unit : Boolean := False;
 587    --  GNATBIND
 588    --  Set to True to indicate that at least one ALI file is an interface ALI:
 589    --  then elaboration flag checks are to be generated in the binder
 590    --  generated file.
 591
 592    Follow_Links : Boolean := False;
 593    --  GNATMAKE
 594    --  Set to True (-eL) to process the project files in trusted mode
 595
 596    Front_End_Inlining : Boolean := False;
 597    --  GNAT
 598    --  Set True to activate inlining by front-end expansion
 599
 600    Inline_Processing_Required : Boolean := False;
 601    --  GNAT
 602    --  Set True if inline processing is required. Inline processing is
 603    --  required if an active Inline pragma is processed. The flag is set
 604    --  for a pragma Inline or Inline_Always that is actually active.
 605
 606    In_Place_Mode : Boolean := False;
 607    --  GNATMAKE
 608    --  Set True to store ALI and object files in place ie in the object
 609    --  directory if these files already exist or in the source directory
 610    --  if not.
 611
 612    Keep_Going : Boolean := False;
 613    --  GNATMAKE, GPRMAKE
 614    --  When True signals to ignore compilation errors and keep
 615    --  processing sources until there is no more work.
 616
 617    Keep_Temporary_Files : Boolean := False;
 618    --  GNATCMD
 619    --  When True the temporary files created by the GNAT driver are not
 620    --  deleted. Set by switch -dn or qualifier /KEEP_TEMPORARY_FILES.
 621
 622    Link_Only : Boolean := False;
 623    --  GNATMAKE, GPRMAKE
 624    --  Set to True to skip compile and bind steps
 625    --  (except when Bind_Only is set to True).
 626
 627    List_Restrictions : Boolean := False;
 628    --  GNATBIND
 629    --  Set to True to list restrictions pragmas that could apply to partition
 630
 631    List_Units : Boolean := False;
 632    --  GNAT
 633    --  List units in the active library for a compilation (-gnatu switch)
 634
 635    List_Dependencies : Boolean := False;
 636    --  GNATMAKE
 637    --  When True gnatmake verifies that the objects are up to date and
 638    --  outputs the list of object dependencies (-M switch).
 639    --  Output depends if -a switch is used or not.
 640    --  This list can be used directly in a Makefile.
 641
 642    List_Representation_Info : Int range 0 .. 3 := 0;
 643    --  GNAT
 644    --  Set non-zero by -gnatR switch to list representation information.
 645    --  The settings are as follows:
 646    --
 647    --    0 = no listing of representation information (default as above)
 648    --    1 = list rep info for user defined record and array types
 649    --    2 = list rep info for all user defined types and objects
 650    --    3 = like 2, but variable fields are decoded symbolically
 651
 652    List_Representation_Info_To_File : Boolean := False;
 653    --  GNAT
 654    --  Set true by -gnatRs switch. Causes information from -gnatR/1/2/3
 655    --  to be written to file.rep (where file is the name of the source
 656    --  file) instead of stdout. For example, if file x.adb is compiled
 657    --  using -gnatR2s then representation info is written to x.adb.ref.
 658
 659    List_Representation_Info_Mechanisms : Boolean := False;
 660    --  GNAT
 661    --  Set true by -gnatRm switch. Causes information on mechanisms to
 662    --  be included in the representation output information.
 663
 664    List_Preprocessing_Symbols : Boolean := False;
 665    --  GNAT, GNATPREP
 666    --  Set to True if symbols for preprocessing a source are to be listed
 667    --  before preprocessing occurs. Set to True by switch -s of gnatprep
 668    --  or -s in preprocessing data file for the compiler.
 669
 670    type Create_Repinfo_File_Proc is access procedure (Src : File_Name_Type);
 671    type Write_Repinfo_Line_Proc  is access procedure (Info : String);
 672    type Close_Repinfo_File_Proc  is access procedure;
 673    --  Types used for procedure addresses below
 674
 675    Create_Repinfo_File_Access : Create_Repinfo_File_Proc := null;
 676    Write_Repinfo_Line_Access  : Write_Repinfo_Line_Proc  := null;
 677    Close_Repinfo_File_Access  : Close_Repinfo_File_Proc  := null;
 678    --  GNAT
 679    --  These three locations are left null when operating in non-compiler
 680    --  (e.g. ASIS mode), but when operating in compiler mode, they are
 681    --  set to point to the three corresponding procedures in Osint-C. The
 682    --  reason for this slightly strange interface is to prevent Repinfo
 683    --  from dragging in Osint in ASIS mode, which would include a lot of
 684    --  unwanted units in the ASIS build.
 685
 686    type Create_List_File_Proc is access procedure (S : String);
 687    type Write_List_Info_Proc  is access procedure (S : String);
 688    type Close_List_File_Proc  is access procedure;
 689    --  Types used for procedure addresses below
 690
 691    Create_List_File_Access : Create_List_File_Proc := null;
 692    Write_List_Info_Access  : Write_List_Info_Proc  := null;
 693    Close_List_File_Access  : Close_List_File_Proc  := null;
 694    --  GNAT
 695    --  These three locations are left null when operating in non-compiler
 696    --  (e.g. from the binder), but when operating in compiler mode, they are
 697    --  set to point to the three corresponding procedures in Osint-C. The
 698    --  reason for this slightly strange interface is to prevent Repinfo
 699    --  from dragging in Osint-C in the binder, which would include unwanted
 700    --  units in the  binder.
 701
 702    Locking_Policy : Character := ' ';
 703    --  GNAT, GNATBIND
 704    --  Set to ' ' for the default case (no locking policy specified).
 705    --  Reset to first character (uppercase) of locking policy name if a
 706    --  valid pragma Locking_Policy is encountered.
 707
 708    Locking_Policy_Sloc : Source_Ptr := No_Location;
 709    --  GNAT, GNATBIND
 710    --  Remember location of previous Locking_Policy pragma. This is used
 711    --  for inconsistency error messages. A value of System_Location is
 712    --  used if the policy is set in package System.
 713
 714    Look_In_Primary_Dir : Boolean := True;
 715    --  GNAT, GNATBIND, GNATMAKE, GNATCLEAN
 716    --  Set to False if a -I- was present on the command line.
 717    --  When True we are allowed to look in the primary directory to locate
 718    --  other source or library files.
 719
 720    Make_Steps : Boolean := False;
 721    --  GNATMAKE
 722    --  Set to True when either Compile_Only, Bind_Only or Link_Only is
 723    --  set to True.
 724
 725    Main_Index : Int := 0;
 726    --  GNATMAKE
 727    --  This is set to non-zero by gnatmake switch -eInnn to indicate that
 728    --  the main program is the nnn unit in a multi-unit source file.
 729
 730    Mapping_File_Name : String_Ptr := null;
 731    --  GNAT
 732    --  File name of mapping between unit names, file names and path names.
 733    --  (given by switch -gnatem)
 734
 735    Maximum_Errors : Int := 9999;
 736    --  GNAT, GNATBIND
 737    --  Maximum default number of errors before compilation is terminated.
 738    --  Can be overridden using -gnatm (GNAT) or -m (GNATBIND) switch.
 739
 740    Maximum_File_Name_Length : Int;
 741    --  GNAT, GNATBIND
 742    --  Maximum number of characters allowed in a file name, not counting the
 743    --  extension, as set by the appropriate switch. If no switch is given,
 744    --  then this value is initialized by Osint to the appropriate value.
 745
 746    Maximum_Processes : Positive := 1;
 747    --  GNATMAKE, GPRMAKE
 748    --  Maximum number of processes that should be spawned to carry out
 749    --  compilations.
 750
 751    Minimal_Recompilation : Boolean := False;
 752    --  GNATMAKE
 753    --  Set to True if minimal recompilation mode requested
 754
 755    Multiple_Unit_Index : Int;
 756    --  GNAT
 757    --  This is set non-zero if the current unit is being compiled in multiple
 758    --  unit per file mode, meaning that the current unit is selected from the
 759    --  sequence of units in the current source file, using the value stored
 760    --  in this variable (e.g. 2 = select second unit in file). A value of
 761    --  zero indicates that we are in normal (one unit per file) mode.
 762
 763    No_Main_Subprogram : Boolean := False;
 764    --  GNATMAKE, GNATBIND
 765    --  Set to True if compilation/binding of a program without main
 766    --  subprogram requested.
 767
 768    No_Run_Time_Mode : Boolean := False;
 769    --  GNAT, GNATBIND
 770    --  This flag is set True if a No_Run_Time pragma is encountered. See
 771    --  spec of Rtsfind for a full description of handling of this pragma.
 772
 773    No_Stdinc : Boolean := False;
 774    --  GNAT, GNATBIND, GNATMAKE, GNATFIND, GNATXREF
 775    --  Set to True if no default source search dirs added to search list
 776
 777    No_Stdlib : Boolean := False;
 778    --  GNATMAKE, GNATBIND, GNATFIND, GNATXREF
 779    --  Set to True if no default library search dirs added to search list
 780
 781    No_Strict_Aliasing : Boolean := False;
 782    --  GNAT
 783    --  Set True if pragma No_Strict_Aliasing with no parameters encountered
 784
 785    Normalize_Scalars : Boolean := False;
 786    --  GNAT, GNATBIND
 787    --  Set True if a pragma Normalize_Scalars applies to the current unit.
 788    --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
 789
 790    Object_Directory_Present : Boolean := False;
 791    --  GNATMAKE
 792    --  Set to True when an object directory is specified with option -D
 793
 794    type Operating_Mode_Type is (Check_Syntax, Check_Semantics, Generate_Code);
 795    Operating_Mode : Operating_Mode_Type := Generate_Code;
 796    --  GNAT
 797    --  Indicates the operating mode of the compiler. The default is generate
 798    --  code, which runs the parser, semantics and backend. Switches can be
 799    --  used to set syntax checking only mode, or syntax and semantics checking
 800    --  only mode. Operating_Mode can also be modified as a result of detecting
 801    --  errors during the compilation process. In particular if any serious
 802    --  error is detected then this flag is reset from Generate_Code to
 803    --  Check_Semantics after generating an error message.
 804
 805    Original_Operating_Mode : Operating_Mode_Type := Generate_Code;
 806    --  GNAT
 807    --  Indicates the original operating mode of the compiler as set by
 808    --  compiler options. This is identical to Operating_Mode except that
 809    --  this is not affected by errors.
 810
 811    Optimization_Level : Int;
 812    pragma Import (C, Optimization_Level, "optimize");
 813    --  This constant reflects the optimization level (0,1,2 for -O0,-O1,-O2)
 814
 815    Output_File_Name_Present : Boolean := False;
 816    --  GNATBIND, GNAT, GNATMAKE, GPRMAKE
 817    --  Set to True when the output C file name is given with option -o
 818    --  for GNATBIND, when the object file name is given with option
 819    --  -gnatO for GNAT or when the executable is given with option -o
 820    --  for GNATMAKE or GPRMAKE.
 821
 822    Output_Linker_Option_List : Boolean := False;
 823    --  GNATBIND
 824    --  True if output of list of linker options is requested (-K switch set)
 825
 826    Output_Object_List : Boolean := False;
 827    --  GNATBIND
 828    --  True if output of list of objects is requested (-O switch set)
 829
 830    Persistent_BSS_Mode : Boolean := False;
 831    --  GNAT
 832    --  True if a Persistent_BSS configuration pragma is in effect, causing
 833    --  potentially persistent data to be placed in the persistent_bss section.
 834
 835    Pessimistic_Elab_Order : Boolean := False;
 836    --  GNATBIND
 837    --  True if pessimistic elaboration order is to be chosen (-p switch set)
 838
 839    Polling_Required : Boolean := False;
 840    --  GNAT
 841    --  Set to True if polling for asynchronous abort is enabled by using
 842    --  the -gnatP option for GNAT.
 843
 844    Preprocessing_Data_File : String_Ptr := null;
 845    --  GNAT
 846    --  Set by switch -gnatep=. The file name of the prepocessing data file.
 847
 848    Print_Generated_Code : Boolean := False;
 849    --  GNAT
 850    --  Set to True to enable output of generated code in source form. This
 851    --  flag is set by the -gnatG switch.
 852
 853    Print_Standard : Boolean := False;
 854    --  GNAT
 855    --  Set to true to enable printing of package standard in source form.
 856    --  This flag is set by the -gnatS switch
 857
 858    Propagate_Exceptions : Boolean := False;
 859    --  GNAT
 860    --  Indicates if subprogram descriptor exception tables should be
 861    --  built for imported subprograms. Set True if a Propagate_Exceptions
 862    --  pragma applies to the extended main unit.
 863
 864    type Usage is (Unknown, Not_In_Use, In_Use);
 865    Project_File_In_Use : Usage := Unknown;
 866    --  GNAT
 867    --  Indicates if a project file is used or not.
 868    --  Set to In_Use by the first SFNP pragma.
 869
 870    Queuing_Policy : Character := ' ';
 871    --  GNAT, GNATBIND
 872    --  Set to ' ' for the default case (no queuing policy specified).
 873    --  Reset to first character (uppercase) of locking policy name if a valid
 874    --  Queuing_Policy pragma is encountered.
 875
 876    Queuing_Policy_Sloc : Source_Ptr := No_Location;
 877    --  GNAT, GNATBIND
 878    --  Remember location of previous Queuing_Policy pragma. This is used
 879    --  for inconsistency error messages. A value of System_Location is
 880    --  used if the policy is set in package System.
 881
 882    Quiet_Output : Boolean := False;
 883    --  GNATMAKE, GNATCLEAN, GPRMAKE
 884    --  Set to True if the tool should not have any output if there are no
 885    --  errors or warnings.
 886
 887    Replace_In_Comments : Boolean := False;
 888    --  GNATPREP
 889    --  Set to True if -C switch used
 890
 891    RTS_Lib_Path_Name : String_Ptr := null;
 892    RTS_Src_Path_Name : String_Ptr := null;
 893    --  GNAT
 894    --  Set to the "adalib" and "adainclude" directories of the run time
 895    --  specified by --RTS=.
 896
 897    RTS_Switch : Boolean := False;
 898    --  GNAT, GNATMAKE, GNATBIND, GNATLS, GNATFIND, GNATXREF
 899    --  Set to True when the --RTS switch is set
 900
 901    Run_Path_Option : Boolean := True;
 902    --  GNATMAKE, GNATLINK
 903    --  Set to False when no run_path_option should be issued to the linker
 904
 905    Search_Directory_Present : Boolean := False;
 906    --  GNAT
 907    --  Set to True when argument is -I. Reset to False when next argument,
 908    --  a search directory path is taken into account. Note that this is
 909    --  quite different from other switches in this section in that it is
 910    --  only set in a transitory manner as a result of scanning a -I switch
 911    --  with no file name, and if set, is an indication that the next argument
 912    --  is to be treated as a file name.
 913
 914    Sec_Stack_Used : Boolean := False;
 915    --  GNAT, GBATBIND
 916    --  Set True if generated code uses the System.Secondary_Stack package.
 917    --  For the binder, set if any unit uses the secondary stack package.
 918
 919    Setup_Projects : Boolean := False;
 920    --  GNAT DRIVER
 921    --  Set to True for GNAT SETUP: the Project Manager creates non existing
 922    --  object, library and exec directories.
 923
 924    Shared_Libgnat : Boolean;
 925    --  GNATBIND
 926    --  Set to True if a shared libgnat is requested by using the -shared
 927    --  option for GNATBIND and to False when using the -static option. The
 928    --  value of this flag is set by Gnatbind.Scan_Bind_Arg.
 929
 930    Stack_Checking_Enabled : Boolean;
 931    --  GNAT
 932    --  Set to indicate if -fstack-check switch is set for the compilation. True
 933    --  means that the switch is set, so that stack checking is enabled. False
 934    --  means that the switch is not set (no stack checking). This value is
 935    --  obtained from the external imported value flag_stack_check in the gcc
 936    --  backend (see Frontend) and may be referenced throughout the compilation
 937    --  phases.
 938
 939    Style_Check : Boolean := False;
 940    --  GNAT
 941    --  Set True to perform style checks. Activates checks carried out
 942    --  in package Style (see body of this package for details of checks)
 943    --  This flag is set True by either the -gnatg or -gnaty switches.
 944
 945    System_Extend_Pragma_Arg : Node_Id := Empty;
 946    --  GNAT
 947    --  Set non-empty if and only if a correct Extend_System pragma was present
 948    --  in which case it points to the argument of the pragma, and the name can
 949    --  be located as Chars (Expression (System_Extend_Pragma_Arg)).
 950
 951    System_Extend_Unit : Node_Id := Empty;
 952    --  GNAT
 953    --  This is set to Empty if GNAT_Mode is set, since pragma Extend_System
 954    --  is never appropriate in GNAT_Mode (and causes troubles, including
 955    --  bogus circularities, if we try to compile the run-time library with
 956    --  a System extension). If GNAT_Mode is not set, then System_Extend_Unit
 957    --  is a copy of the value set in System_Extend_Pragma_Arg.
 958
 959    Subunits_Missing : Boolean := False;
 960    --  GNAT
 961    --  This flag is set true if missing subunits are detected with code
 962    --  generation active. This causes code generation to be skipped.
 963
 964    Suppress_Checks : Boolean := False;
 965    --  GNAT
 966    --  Set to True if -gnatp (suppress all checks) switch present.
 967
 968    Suppress_Options : Suppress_Array;
 969    --  GNAT
 970    --  Flags set True to suppress corresponding check, i.e. add an implicit
 971    --  pragma Suppress at the outer level of each unit compiled. Note that
 972    --  these suppress actions can be overridden by the use of the Unsuppress
 973    --  pragma. This variable is initialized by Osint.Initialize.
 974
 975    Suppress_Back_Annotation : Boolean := False;
 976    --  GNAT
 977    --  This flag is set True if back annotation of representation information
 978    --  is to be suppressed. This is set if neither -gnatt or -gnatR0-3 is set.
 979    --  This avoids unnecessary time being spent on back annotation.
 980
 981    Table_Factor : Int := 1;
 982    --  GNAT
 983    --  Factor by which all initial table sizes set in Alloc are multiplied.
 984    --  Used in Table to calculate initial table sizes (the initial table size
 985    --  is the value in Alloc, used as the Table_Initial parameter value,
 986    --  multiplied by the factor given here. The default value is used if no
 987    --  -gnatT switch appears.
 988
 989    Task_Dispatching_Policy : Character := ' ';
 990    --  GNAT, GNATBIND
 991    --  Set to ' ' for the default case (no task dispatching policy specified).
 992    --  Reset to first character (uppercase) of task dispatching policy name
 993    --  if a valid Task_Dispatching_Policy pragma is encountered.
 994
 995    Task_Dispatching_Policy_Sloc : Source_Ptr := No_Location;
 996    --  GNAT, GNATBIND
 997    --  Remember location of previous Task_Dispatching_Policy pragma. This is
 998    --  used for inconsistency error messages. A value of System_Location is
 999    --  used if the policy is set in package System.
1000
1001    Tasking_Used : Boolean := False;
1002    --  Set True if any tasking construct is encountered. Used to activate the
1003    --  output of the Q, L and T lines in ALI files.
1004
1005    Time_Slice_Set : Boolean := False;
1006    --  GNATBIND
1007    --  Set True if a pragma Time_Slice is processed in the main unit, or
1008    --  if the -gnatTnn switch is present to set a time slice value.
1009
1010    Time_Slice_Value : Nat;
1011    --  GNATBIND
1012    --  Time slice value. Valid only if Time_Slice_Set is True, i.e. if
1013    --  Time_Slice pragma has been processed. Set to the time slice value in
1014    --  microseconds. Negative values are stored as zero, and the value is not
1015    --  larger than 1_000_000_000 (1000 seconds). Values larger than this are
1016    --  reset to this maximum. This can also be set with the -gnatTnn switch.
1017
1018    Tolerate_Consistency_Errors : Boolean := False;
1019    --  GNATBIND
1020    --  Tolerate time stamp and other consistency errors. If this flag is set to
1021    --  True (-t), then inconsistencies result in warnings rather than errors.
1022
1023    Tree_Output : Boolean := False;
1024    --  GNAT
1025    --  Set to True (-gnatt) to generate output tree file
1026
1027    Try_Semantics : Boolean := False;
1028    --  GNAT
1029    --  Flag set to force attempt at semantic analysis, even if parser errors
1030    --  occur. This will probably cause blowups at this stage in the game. On
1031    --  the other hand, most such blowups will be caught cleanly and simply
1032    --  say compilation abandoned. This flag is set to True by -gnatq or -gnatQ.
1033
1034    Undefined_Symbols_Are_False : Boolean := False;
1035    --  GNAT, GNATPREP
1036    --  Set to True by switch -u of gnatprep or -u in the preprocessing data
1037    --  file for the compiler. Indicates that while preprocessing sources,
1038    --  symbols that are not defined have the value FALSE.
1039
1040    Unique_Error_Tag : Boolean := Tag_Errors;
1041    --  GNAT
1042    --  Indicates if error messages are to be prefixed by the string error:
1043    --  Initialized from Tag_Errors, can be forced on with the -gnatU switch.
1044
1045    Universal_Addressing_On_AAMP : Boolean := False;
1046    --  GNAAMP
1047    --  Indicates if library-level objects should be accessed and updated using
1048    --  universal addressing instructions on the AAMP architecture. This flag is
1049    --  set to True when pragma Universal_Data is given as a configuration
1050    --  pragma.
1051
1052    Unreserve_All_Interrupts : Boolean := False;
1053    --  GNAT, GNATBIND
1054    --  Normally set False, set True if a valid Unreserve_All_Interrupts pragma
1055    --  appears anywhere in the main unit for GNAT, or if any ALI file has the
1056    --  corresponding attribute set in GNATBIND.
1057
1058    Upper_Half_Encoding : Boolean := False;
1059    --  GNAT
1060    --  Normally set False, indicating that upper half ASCII characters are
1061    --  used in the normal way to represent themselves. If the wide character
1062    --  encoding method uses the upper bit for this encoding, then this flag is
1063    --  set True, and upper half characters in the source indicate the start of
1064    --  a wide character sequence.
1065
1066    Usage_Requested : Boolean := False;
1067    --  GNAT, GNATBIND, GNATMAKE
1068    --  Set to True if -h (-gnath for the compiler) switch encountered
1069    --  requesting usage information
1070
1071    Use_Pragma_Linker_Constructor : Boolean := False;
1072    --  GNATBIND
1073    --  True if pragma Linker_Constructor applies to adainit
1074
1075    Use_VADS_Size : Boolean := False;
1076    --  GNAT
1077    --  Set to True if a valid pragma Use_VADS_Size is processed
1078
1079    Validity_Checks_On  : Boolean := True;
1080    --  GNAT
1081    --  This flag determines if validity checking is on or off. The initial
1082    --  state is on, and the required default validity checks are active. The
1083    --  actual set of checks that is performed if Validity_Checks_On is set is
1084    --  defined by the switches in package Validsw. The Validity_Checks_On flag
1085    --  is controlled by pragma Validity_Checks (On | Off), and also some
1086    --  generated compiler code (typically code that has to do with validity
1087    --  check generation) is compiled with this flag set to False. This flag is
1088    --  set to False by the -gnatp switch.
1089
1090    Verbose_Mode : Boolean := False;
1091    --  GNAT, GNATBIND, GNATMAKE, GNATLINK, GNATLS, GNATNAME, GNATCLEAN,
1092    --  GPRMAKE
1093    --  Set to True to get verbose mode (full error message text and location
1094    --  information sent to standard output, also header, copyright and summary)
1095
1096    type Verbosity_Level_Type is (None, Low, Medium, High);
1097    Verbosity_Level : Verbosity_Level_Type := High;
1098    --  GNATMAKE, GPRMAKE
1099    --  Modified by gnatmake or gprmake switches -v, -vl, -vm, -vh. Indicates
1100    --  the level of verbosity of informational messages:
1101    --
1102    --  In Low Verbosity, the reasons why a source is recompiled, the name
1103    --  of the executable and the reason it must be rebuilt is output.
1104    --
1105    --  In Medium Verbosity, additional lines are output for each ALI file
1106    --  that is checked.
1107    --
1108    --  In High Verbosity, additional lines are output when the ALI file
1109    --  is part of an Ada library, is read-only or is part of the runtime.
1110
1111    Warn_On_Ada_2005_Compatibility : Boolean := True;
1112    --  GNAT
1113    --  Set to True to generate all warnings on Ada 2005 compatibility issues,
1114    --  including warnings on Ada 2005 obsolescent features used in Ada 2005
1115    --  mode. Set False by -gnatwY.
1116
1117    Warn_On_Assumed_Low_Bound : Boolean := True;
1118    --  GNAT
1119    --  Set to True to activate warnings for string parameters that are indexed
1120    --  with literals or S'Length, presumably assuming a lower bound of one. Set
1121    --  False by -gnatwW.
1122
1123    Warn_On_Bad_Fixed_Value : Boolean := False;
1124    --  GNAT
1125    --  Set to True to generate warnings for static fixed-point expression
1126    --  values that are not an exact multiple of the small value of the type.
1127
1128    Warn_On_Constant : Boolean := False;
1129    --  GNAT
1130    --  Set to True to generate warnings for variables that could be declared
1131    --  as constants. Modified by use of -gnatwk/K.
1132
1133    Warn_On_Deleted_Code : Boolean := False;
1134    --  GNAT
1135    --  Set to True to generate warnings for code deleted by the front end
1136    --  for conditional statements whose outcome is known at compile time.
1137    --  Modified by use of -gnatwt/T.
1138
1139    Warn_On_Dereference : Boolean := False;
1140    --  GNAT
1141    --  Set to True to generate warnings for implicit dereferences for array
1142    --  indexing and record component access. Modified by use of -gnatwd/D.
1143
1144    Warn_On_Export_Import : Boolean := True;
1145    --  GNAT
1146    --  Set to True to generate warnings for suspicious use of export or
1147    --  import pragmas. Modified by use of -gnatwx/X.
1148
1149    Warn_On_Hiding : Boolean := False;
1150    --  GNAT
1151    --  Set to True to generate warnings if a declared entity hides another
1152    --  entity. The default is that this warning is suppressed.
1153
1154    Warn_On_Modified_Unread : Boolean := False;
1155    --  GNAT
1156    --  Set to True to generate warnings if a variable is assigned but is never
1157    --  read. The default is that this warning is suppressed. Also controls
1158    --  warnings about assignments whose value is never read.
1159
1160    Warn_On_No_Value_Assigned : Boolean := True;
1161    --  GNAT
1162    --  Set to True to generate warnings if no value is ever assigned to a
1163    --  variable that is at least partially uninitialized. Set to false to
1164    --  suppress such warnings. The default is that such warnings are enabled.
1165
1166    Warn_On_Obsolescent_Feature : Boolean := False;
1167    --  GNAT
1168    --  Set to True to generate warnings on use of any feature in Annex or if a
1169    --  subprogram is called for which a pragma Obsolescent applies.
1170
1171    Warn_On_Questionable_Missing_Parens : Boolean := False;
1172    --  GNAT
1173    --  Set to True to generate warnings for cases where parenthese are missing
1174    --  and the usage is questionable, because the intent is unclear.
1175
1176    Warn_On_Redundant_Constructs : Boolean := False;
1177    --  GNAT
1178    --  Set to True to generate warnings for redundant constructs (e.g. useless
1179    --  assignments/conversions). The default is that this warning is disabled.
1180
1181    Warn_On_Unchecked_Conversion : Boolean := True;
1182    --  GNAT
1183    --  Set to True to generate warnings for unchecked conversions that may have
1184    --  non-portable semantics (e.g. because sizes of types differ). The default
1185    --  is that this warning is enabled.
1186
1187    Warn_On_Unrecognized_Pragma : Boolean := True;
1188    --  GNAT
1189    --  Set to True to generate warnings for unrecognized pragmas. The default
1190    --  is that this warning is enabled.
1191
1192    type Warning_Mode_Type is (Suppress, Normal, Treat_As_Error);
1193    Warning_Mode : Warning_Mode_Type := Normal;
1194    --  GNAT, GNATBIND
1195    --  Controls treatment of warning messages. If set to Suppress, warning
1196    --  messages are not generated at all. In Normal mode, they are generated
1197    --  but do not count as errors. In Treat_As_Error mode, warning messages
1198    --  are generated and are treated as errors.
1199
1200    Wide_Character_Encoding_Method : WC_Encoding_Method := WCEM_Brackets;
1201    --  GNAT
1202    --  Method used for encoding wide characters in the source program. See
1203    --  description of type in unit System.WCh_Con for a list of the methods
1204    --  that are currently supported. Note that brackets notation is always
1205    --  recognized in source programs regardless of the setting of this
1206    --  variable. The default setting causes only the brackets notation to be
1207    --  recognized. If this is the main unit, this setting also controls the
1208    --  output of the W=? parameter in the ALI file, which is used to provide
1209    --  the default for Wide_Text_IO files.
1210
1211    Xref_Active : Boolean := True;
1212    --  GNAT
1213    --  Set if cross-referencing is enabled (i.e. xref info in ALI files)
1214
1215    ----------------------------
1216    -- Configuration Settings --
1217    ----------------------------
1218
1219    --  These are settings that are used to establish the mode at the start of
1220    --  each unit. The values defined below can be affected either by command
1221    --  line switches, or by the use of appropriate configuration pragmas in the
1222    --  gnat.adc file.
1223
1224    Ada_Version_Config : Ada_Version_Type;
1225    --  GNAT
1226    --  This is the value of the configuration switch for the Ada 83 mode, as
1227    --  set by the command line switches -gnat83/95/05, and possibly modified by
1228    --  the use of configuration pragmas Ada_83/Ada95/Ada05. This switch is used
1229    --  to set the initial value for Ada_Version mode at the start of analysis
1230    --  of a unit. Note however, that the setting of this flag is ignored for
1231    --  internal and predefined units (which are always compiled in the most up
1232    --  to date version of Ada).
1233
1234    Ada_Version_Explicit_Config : Ada_Version_Type;
1235    --  GNAT
1236    --  This is set in the same manner as Ada_Version_Config. The difference is
1237    --  that the setting of this flag is not ignored for internal and predefined
1238    --  units, which for some purposes do indeed access this value, regardless
1239    --  of the fact that they are compiled the the most up to date ada version).
1240
1241    Assertions_Enabled_Config : Boolean;
1242    --  GNAT
1243    --  This is the value of the configuration switch for assertions enabled
1244    --  mode, as possibly set by the command line switch -gnata, and possibly
1245    --  modified by the use of the configuration pragma Assertion_Policy.
1246
1247    Debug_Pragmas_Enabled_Config : Boolean;
1248    --  GNAT
1249    --  This is the value of the configuration switch for debug pragmas enabled
1250    --  mode, as possibly set by the command line switch -gnata and possibly
1251    --  modified by the use of the configuration pragma Debug_Policy.
1252
1253    Dynamic_Elaboration_Checks_Config : Boolean := False;
1254    --  GNAT
1255    --  Set True for dynamic elaboration checking mode, as set by the -gnatE
1256    --  switch or by the use of pragma Elaboration_Checking (Dynamic).
1257
1258    Exception_Locations_Suppressed_Config : Boolean := False;
1259    --  GNAT
1260    --  Set True by use of the configuration pragma Suppress_Exception_Messages
1261
1262    Extensions_Allowed_Config : Boolean;
1263    --  GNAT
1264    --  This is the flag that indicates whether extensions are allowed. It can
1265    --  be set True either by use of the -gnatX switch, or by use of the
1266    --  configuration pragma Extensions_Allowed (On). It is always set to True
1267    --  for internal GNAT units, since extensions are always permitted in such
1268    --  units.
1269
1270    External_Name_Exp_Casing_Config : External_Casing_Type;
1271    --  GNAT
1272    --  This is the value of the configuration switch that controls casing of
1273    --  external symbols for which an explicit external name is given. It can be
1274    --  set to Uppercase by the command line switch -gnatF, and further modified
1275    --  by the use of the configuration pragma External_Name_Casing in the
1276    --  gnat.adc file. This flag is used to set the initial value for
1277    --  External_Name_Exp_Casing at the start of analyzing each unit. Note
1278    --  however that the setting of this flag is ignored for internal and
1279    --  predefined units (which are always compiled with As_Is mode).
1280
1281    External_Name_Imp_Casing_Config : External_Casing_Type;
1282    --  GNAT
1283    --  This is the value of the configuration switch that controls casing of
1284    --  external symbols where the external name is implicitly given. It can be
1285    --  set to Uppercase by the command line switch -gnatF, and further modified
1286    --  by the use of the configuration pragma External_Name_Casing in the
1287    --  gnat.adc file. This flag is used to set the initial value for
1288    --  External_Name_Imp_Casing at the start of analyzing each unit. Note
1289    --  however that the setting of this flag is ignored for internal and
1290    --  predefined units (which are always compiled with Lowercase mode).
1291
1292    Persistent_BSS_Mode_Config : Boolean;
1293    --  GNAT
1294    --  This is the value of the configuration switch that controls whether
1295    --  potentially persistent data is to be placed in the persistent_bss
1296    --  section. It can be set True by use of the pragma Persistent_BSS.
1297    --  This flag is used to set the initial value of Persistent_BSS_Mode
1298    --  at the start of each compilation unit, except that it is always
1299    --  set False for predefined units.
1300
1301    Polling_Required_Config : Boolean;
1302    --  GNAT
1303    --  This is the value of the configuration switch that controls polling
1304    --  mode. It can be set True by the command line switch -gnatP, and then
1305    --  further modified by the use of pragma Polling in the gnat.adc file. This
1306    --  flag is used to set the initial value for Polling_Required at the start
1307    --  of analyzing each unit.
1308
1309    Use_VADS_Size_Config : Boolean;
1310    --  GNAT
1311    --  This is the value of the configuration switch that controls the use of
1312    --  VADS_Size instead of Size whereever the attribute Size is used. It can
1313    --  be set True by the use of the pragma Use_VADS_Size in the gnat.adc file.
1314    --  This flag is used to set the initial value for Use_VADS_Size at the
1315    --  start of analyzing each unit. Note however that the setting of this flag
1316    --  is ignored for internal and predefined units (which are always compiled
1317    --  with the standard Size semantics).
1318
1319    type Config_Switches_Type is private;
1320    --  Type used to save values of the switches set from Config values
1321
1322    procedure Save_Opt_Config_Switches (Save : out Config_Switches_Type);
1323    --  This procedure saves the current values of the switches which are
1324    --  initialized from the above Config values, and then resets these switches
1325    --  according to the Config value settings.
1326
1327    procedure Set_Opt_Config_Switches
1328      (Internal_Unit : Boolean;
1329       Main_Unit     : Boolean);
1330    --  This procedure sets the switches to the appropriate initial values. The
1331    --  parameter Internal_Unit is True for an internal or predefined unit, and
1332    --  affects the way the switches are set (see above). Main_Unit is true if
1333    --  switches are being set for the main unit (this affects setting of the
1334    --  assert/debug pragm switches, which are normally set false by default for
1335    --  an internal unit, except when the internal unit is the main unit, in
1336    --  which case we use the command line settings).
1337
1338    procedure Restore_Opt_Config_Switches (Save : Config_Switches_Type);
1339    --  This procedure restores a set of switch values previously saved by a
1340    --  call to Save_Opt_Switches.
1341
1342    procedure Register_Opt_Config_Switches;
1343    --  This procedure is called after processing the gnat.adc file to record
1344    --  the values of the Config switches, as possibly modified by the use of
1345    --  command line switches and configuration pragmas.
1346
1347    ------------------------
1348    -- Other Global Flags --
1349    ------------------------
1350
1351    Expander_Active : Boolean := False;
1352    --  A flag that indicates if expansion is active (True) or deactivated
1353    --  (False). When expansion is deactivated all calls to expander routines
1354    --  have no effect. Note that the initial setting of False is merely to
1355    --  prevent saving of an undefined value for an initial call to the
1356    --  Expander_Mode_Save_And_Set procedure. For more information on the use of
1357    --  this flag, see package Expander. Indeed this flag might more logically
1358    --  be in the spec of Expander, but it is referenced by Errout, and it
1359    --  really seems wrong for Errout to depend on Expander.
1360
1361    -----------------------
1362    -- Tree I/O Routines --
1363    -----------------------
1364
1365    procedure Tree_Read;
1366    --  Reads switch settings from current tree file using Tree_Read
1367
1368    procedure Tree_Write;
1369    --  Writes out switch settings to current tree file using Tree_Write
1370
1371    --------------------------
1372    -- ASIS Version Control --
1373    --------------------------
1374
1375    --  These two variables (Tree_Version_String and Tree_ASIS_Version_Number)
1376    --  are supposed to be used in the GNAT/ASIS version check performed in
1377    --  the ASIS code (this package is also a part of the ASIS implementation).
1378    --  They are set by Tree_Read procedure, so they represent the version
1379    --  number (and the version string) of the compiler which has created the
1380    --  tree, and they are supposed to be compared with the corresponding values
1381    --  from the Gnatvsn package which is a part of ASIS implementation.
1382
1383    Tree_Version_String : String_Access;
1384    --  Used to store the compiler version string read from a tree file to check
1385    --  if it is from the same date as stored in the version string in Gnatvsn.
1386    --  We require that ASIS Pro can be used only with GNAT Pro, but we allow
1387    --  non-Pro ASIS and ASIS-based tools to be used with any version of the
1388    --  GNAT compiler. Therefore, we need the possibility to compare the dates
1389    --  of the corresponding source sets, using version strings that may be
1390    --  of different lengths.
1391
1392    Tree_ASIS_Version_Number : Int;
1393    --  Used to store the ASIS version number read from a tree file to check if
1394    --  it is the same as stored in the ASIS version number in Gnatvsn.
1395
1396 private
1397
1398    --  The following type is used to save and restore settings of switches in
1399    --  Opt that represent the configuration (i.e. result of config pragmas).
1400
1401    --  Note that Ada_Version_Explicit is not included, since this is a sticky
1402    --  flag that once set does not get reset, since the whole idea of this flag
1403    --  is to record the setting for the main unit.
1404
1405    type Config_Switches_Type is record
1406       Ada_Version                    : Ada_Version_Type;
1407       Ada_Version_Explicit           : Ada_Version_Type;
1408       Assertions_Enabled             : Boolean;
1409       Debug_Pragmas_Enabled          : Boolean;
1410       Dynamic_Elaboration_Checks     : Boolean;
1411       Exception_Locations_Suppressed : Boolean;
1412       Extensions_Allowed             : Boolean;
1413       External_Name_Exp_Casing       : External_Casing_Type;
1414       External_Name_Imp_Casing       : External_Casing_Type;
1415       Persistent_BSS_Mode            : Boolean;
1416       Polling_Required               : Boolean;
1417       Use_VADS_Size                  : Boolean;
1418    end record;
1419
1420 end Opt;