1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                                  O P T                                   --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 1992-2013, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT is free software;  you can  redistribute it  and/or modify it under --
12-- terms of the  GNU General Public License as published  by the Free Soft- --
13-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
14-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
15-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
16-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNAT was originally developed  by the GNAT team at  New York University. --
28-- Extensive contributions were provided by Ada Core Technologies Inc.      --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--  This package contains global flags set by the initialization routine from
33--  the command line and referenced throughout the compiler, the binder, or
34--  other GNAT tools. The comments indicate which options are used by which
35--  programs (GNAT, GNATBIND, GNATLINK, GNATMAKE, GPRMAKE, etc).
36
37--  Some flags are labelled "PROJECT MANAGER". These are used by tools that
38--  use the Project Manager. These tools include gnatmake, gnatname, the gnat
39--  driver, gnatclean, gprbuild and gprclean.
40
41with Hostparm; use Hostparm;
42with Types;    use Types;
43
44pragma Warnings (Off);
45--  This package is used also by gnatcoll
46with System.Strings; use System.Strings;
47with System.WCh_Con; use System.WCh_Con;
48pragma Warnings (On);
49
50package Opt is
51
52   ----------------------
53   -- Checksum Control --
54   ----------------------
55
56   --  Checksums are computed for sources to check for sources being the same
57   --  from a compilation point of view (e.g. spelling of identifiers and
58   --  white space layout do not count in this computation).
59
60   --  The way the checksum is computed has evolved across the various versions
61   --  of GNAT. When gprbuild is called with -m, the checksums must be computed
62   --  the same way in gprbuild as it was in the GNAT version of the compiler.
63   --  The different ways are
64
65   --    Version 6.4 and later:
66
67   --      The Accumulate_Token_Checksum procedure is called after each numeric
68   --      literal and each identifier/keyword. For keywords, Tok_Identifier is
69   --      used in the call to Accumulate_Token_Checksum.
70
71   --    Versions 5.04 to 6.3:
72
73   --      For keywords, the token value were used in the call to procedure
74   --      Accumulate_Token_Checksum. Type Token_Type did not include Tok_Some.
75
76   --    Versions 5.03:
77
78   --      For keywords, the token value were used in the call to
79   --      Accumulate_Token_Checksum. Type Token_Type did not include
80   --      Tok_Interface, Tok_Overriding, Tok_Synchronized and Tok_Some.
81
82   --    Versions 5.02 and before:
83
84   --      No calls to procedure Accumulate_Token_Checksum (the checksum
85   --      mechanism was introduced in version 5.03).
86
87   --  To signal to the scanner whether Accumulate_Token_Checksum needs to be
88   --  called and what versions to call, the following Boolean flags are used:
89
90   Checksum_Accumulate_Token_Checksum : Boolean := True;
91   --  GPRBUILD
92   --  Set to False by gprbuild when the version of GNAT is 5.02 or before. If
93   --  this switch is False, then we do not call Accumulate_Token_Checksum, so
94   --  the setting of the following two flags is irrelevant.
95
96   Checksum_GNAT_6_3 : Boolean := False;
97   --  GPRBUILD
98   --  Set to True by gprbuild when the version of GNAT is 6.3 or before.
99
100   Checksum_GNAT_5_03 : Boolean := False;
101   --  GPRBUILD
102   --  Set to True by gprbuild when the version of GNAT is 5.03 or before.
103
104   ----------------------------------------------
105   -- Settings of Modes for Current Processing --
106   ----------------------------------------------
107
108   --  The following mode values represent the current state of processing.
109   --  The values set here are the default values. Unless otherwise noted,
110   --  the value may be reset in Switch-? with an appropriate switch. In
111   --  some cases, the values can also be modified by pragmas, and in the
112   --  case of some binder variables, Gnatbind.Scan_Bind_Arg may modify
113   --  the default values.
114
115   type Ada_Version_Type is (Ada_83, Ada_95, Ada_2005, Ada_2012);
116   pragma Ordered (Ada_Version_Type);
117   --  Versions of Ada for Ada_Version below. Note that these are ordered,
118   --  so that tests like Ada_Version >= Ada_95 are legitimate and useful.
119   --  Think twice before using "="; Ada_Version >= Ada_2012 is more likely
120   --  what you want, because it will apply to future versions of the language.
121
122   Ada_Version_Default : constant Ada_Version_Type := Ada_2005;
123   pragma Warnings (Off, Ada_Version_Default);
124   --  GNAT
125   --  Default Ada version if no switch given. The Warnings off is to kill
126   --  constant condition warnings.
127   --
128   --  WARNING: some scripts rely on the format of this line of code. Any
129   --  change must be coordinated with the scripts requirements.
130
131   Ada_Version : Ada_Version_Type := Ada_Version_Default;
132   --  GNAT
133   --  Current Ada version for compiler, as set by configuration pragmas,
134   --  compiler switches, or implicitly (to Ada_Version_Runtime) when a
135   --  predefined or internal file is compiled.
136
137   Ada_Version_Explicit : Ada_Version_Type := Ada_Version_Default;
138   --  GNAT
139   --  Like Ada_Version, but does not get set implicitly for predefined
140   --  or internal units, so it reflects the Ada version explicitly set
141   --  using configuration pragmas or compiler switches (or if neither
142   --  appears, it remains set to Ada_Version_Default). This is used in
143   --  the rare cases (notably for pragmas Preelaborate_05 and Pure_05/12)
144   --  where in the run-time we want the explicit version set.
145
146   Ada_Version_Runtime : Ada_Version_Type := Ada_2012;
147   --  GNAT
148   --  Ada version used to compile the runtime. Used to set Ada_Version (but
149   --  not Ada_Version_Explicit) when compiling predefined or internal units.
150
151   Ada_Final_Suffix : constant String := "final";
152   Ada_Final_Name   : String_Ptr := new String'("ada" & Ada_Final_Suffix);
153   --  GNATBIND
154   --  The name of the procedure that performs the finalization at the end of
155   --  execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
156
157   Ada_Init_Suffix : constant String := "init";
158   Ada_Init_Name   : String_Ptr := new String'("ada" & Ada_Init_Suffix);
159   --  GNATBIND
160   --  The name of the procedure that performs initialization at the start
161   --  of execution. This variable may be modified by Gnatbind.Scan_Bind_Arg.
162
163   Ada_Main_Name_Suffix : constant String := "main";
164   --  GNATBIND
165   --  The suffix for Ada_Main_Name. Defined as a constant here so that it
166   --  can be referenced in a uniform manner to create either the default
167   --  value of Ada_Main_Name (declared below), or the non-default name
168   --  set by Gnatbind.Scan_Bind_Arg.
169
170   Ada_Main_Name : String_Ptr := new String'("ada_" & Ada_Main_Name_Suffix);
171   --  GNATBIND
172   --  The name of the Ada package generated by the binder (when in Ada mode).
173   --  This variable may be modified by Gnatbind.Scan_Bind_Arg.
174
175   Address_Clause_Overlay_Warnings : Boolean := True;
176   --  GNAT
177   --  Set False to disable address clause warnings. Modified by use of
178   --  -gnatwo/O.
179
180   Address_Is_Private : Boolean := False;
181   --  GNAT, GNATBIND
182   --  Set True if package System has the line "type Address is private;"
183
184   All_Errors_Mode : Boolean := False;
185   --  GNAT
186   --  Flag set to force display of multiple errors on a single line and
187   --  also repeated error messages for references to undefined identifiers
188   --  and certain other repeated error messages. Set by use of -gnatf.
189
190   All_Sources : Boolean := False;
191   --  GNATBIND
192   --  Set to True to require all source files to be present. This flag is
193   --  directly modified by gnatmake to affect the shared binder routines.
194
195   Alternate_Main_Name : String_Ptr := null;
196   --  GNATBIND
197   --  Set to non null when Bind_Alternate_Main_Name is True. This value
198   --  is modified as needed by Gnatbind.Scan_Bind_Arg.
199
200   ASIS_Mode : Boolean := False;
201   --  GNAT
202   --  Enable semantic checks and tree transformations that are important
203   --  for ASIS but that are usually skipped if Operating_Mode is set to
204   --  Check_Semantics. This flag does not have the corresponding option to set
205   --  it ON. It is set ON when Tree_Output is set ON, it can also be set ON
206   --  from the code of GNSA-based tool (a client may need to set ON the
207   --  Back_Annotate_Rep_Info flag in this case. At the moment this does not
208   --  make very much sense, because GNSA cannot do back annotation).
209
210   Assertions_Enabled : Boolean := False;
211   --  GNAT
212   --  Enable assertions made using pragma Assert
213
214   Assume_No_Invalid_Values : Boolean := False;
215   --  GNAT Normally, in accordance with (RM 13.9.1 (9-11)) the front end
216   --  assumes that values could have invalid representations, unless it can
217   --  clearly prove that the values are valid. If this switch is set (by
218   --  pragma Assume_No_Invalid_Values (Off)), then the compiler assumes values
219   --  are valid and in range of their representations. This feature is now
220   --  fully enabled in the compiler.
221
222   Back_Annotate_Rep_Info : Boolean := False;
223   --  GNAT
224   --  If set True, enables back annotation of representation information
225   --  by gigi, even in -gnatc mode. This is set True by the use of -gnatR
226   --  (list representation information) or -gnatt (generate tree). It is
227   --  also set true if certain Unchecked_Conversion instantiations require
228   --  checking based on annotated values.
229
230   Back_End_Handles_Limited_Types : Boolean;
231   --  This flag is set true if the back end can properly handle limited or
232   --  other by reference types, and avoid copies. If this flag is False, then
233   --  the front end does special expansion for if/case expressions to make
234   --  sure that no copy occurs. If the flag is True, then the expansion for
235   --  if and case expressions relies on the back end properly handling things.
236   --  Currently the default is False for all cases (set in gnat1drv). The
237   --  default can be modified using -gnatd.L (sets the flag True). This is
238   --  used to test the possibility of having the backend handle this.
239
240   Bind_Alternate_Main_Name : Boolean := False;
241   --  GNATBIND
242   --  True if main should be called Alternate_Main_Name.all.
243   --  This variable may be set to True by Gnatbind.Scan_Bind_Arg.
244
245   Bind_Main_Program : Boolean := True;
246   --  GNATBIND
247   --  Set to False if not binding main Ada program
248
249   Bind_For_Library : Boolean := False;
250   --  GNATBIND
251   --  Set to True if the binder needs to generate a file designed for building
252   --  a library. May be set to True by Gnatbind.Scan_Bind_Arg.
253
254   Bind_Only : Boolean := False;
255   --  GNATMAKE, GPRMAKE, GPRBUILD
256   --  Set to True to skip compile and link steps
257   --  (except when Compile_Only and/or Link_Only are True).
258
259   Blank_Deleted_Lines : Boolean := False;
260   --  GNAT, GNATPREP
261   --  Output empty lines for each line of preprocessed input that is deleted
262   --  in the output, including preprocessor lines starting with a '#'.
263
264   Brief_Output : Boolean := False;
265   --  GNAT, GNATBIND
266   --  Force brief error messages to standard error, even if verbose mode is
267   --  set (so that main error messages go to standard output).
268
269   Build_Bind_And_Link_Full_Project : Boolean := False;
270   --  GNATMAKE
271   --  Set to True to build, bind and link all the sources of a project file
272   --  (switch -B)
273
274   Check_Aliasing_Of_Parameters : Boolean := False;
275   --  GNAT
276   --  Set to True to detect whether subprogram parameters and function results
277   --  alias the same object(s).
278
279   Check_Float_Overflow : Boolean := False;
280   --  GNAT
281   --  Set to True to check that operations on predefined unconstrained float
282   --  types (e.g. Float, Long_Float) do not overflow and generate infinities
283   --  or invalid values. Set by the Check_Float_Overflow pragma, or by use
284   --  of the -gnateF switch.
285
286   Check_Object_Consistency : Boolean := False;
287   --  GNATBIND, GNATMAKE
288   --  Set to True to check whether every object file is consistent with
289   --  its corresponding ada library information (ALI) file. An object
290   --  file is inconsistent with the corresponding ALI file if the object
291   --  file does not exist or if it has an older time stamp than the ALI file.
292   --  Default above is for GNATBIND. GNATMAKE overrides this default to
293   --  True (see Make.Initialize) since we normally do need to check source
294   --  consistencies in gnatmake.
295
296   Check_Only : Boolean := False;
297   --  GNATBIND
298   --  Set to True to do checks only, no output of binder file
299
300   Check_Policy_List : Node_Id := Empty;
301   --  GNAT
302   --  This points to the list of N_Pragma nodes for Check_Policy pragmas
303   --  that are linked through the Next_Pragma fields, with the list being
304   --  terminated by Empty. The order is most recently processed first. Note
305   --  that Push_Scope and Pop_Scope in Sem_Ch8 save and restore the value
306   --  of this variable, implementing the required scope control for pragmas
307   --  appearing a declarative part.
308
309   Check_Readonly_Files : Boolean := False;
310   --  GNATMAKE
311   --  Set to True to check readonly files during the make process
312
313   Check_Source_Files : Boolean := True;
314   --  GNATBIND, GNATMAKE
315   --  Set to True to enable consistency checking for any source files that
316   --  are present (i.e. date must match the date in the library info file).
317   --  Set to False for object file consistency check only. This flag is
318   --  directly modified by gnatmake, to affect the shared binder routines.
319
320   Check_Switches : Boolean := False;
321   --  GNATMAKE, GPRMAKE, GPBUILD
322   --  Set to True to check compiler options during the make process
323
324   Check_Unreferenced : Boolean := False;
325   --  GNAT
326   --  Set to True to enable checking for unreferenced entities other
327   --  than formal parameters (for which see Check_Unreferenced_Formals)
328   --  Modified by use of -gnatwu/U.
329
330   Check_Unreferenced_Formals : Boolean := False;
331   --  GNAT
332   --  Set to True to check for unreferenced formals. This is turned on by
333   --  -gnatwa/wf/wu and turned off by -gnatwA/wF/wU.
334
335   Check_Validity_Of_Parameters : Boolean := False;
336   --  GNAT
337   --  Set to True to check for proper scalar initialization of subprogram
338   --  parameters on both entry and exit. Turned on by??? turned off by???
339
340   Check_Withs : Boolean := False;
341   --  GNAT
342   --  Set to True to enable checking for unused withs, and also the case
343   --  of withing a package and using none of the entities in the package.
344   --  Modified by use of -gnatwu/U.
345
346   CodePeer_Mode : Boolean := False;
347   --  GNAT, GNATBIND
348   --  Enable full CodePeer mode (SCIL generation, disable switches that
349   --  interact badly with it, etc...).
350
351   Commands_To_Stdout : Boolean := False;
352   --  GNATMAKE
353   --  True if echoed commands to be written to stdout instead of stderr
354
355   Comment_Deleted_Lines : Boolean := False;
356   --  GNATPREP
357   --  True if source lines removed by the preprocessor should be commented
358   --  in the output file.
359
360   Compile_Only : Boolean := False;
361   --  GNATMAKE, GNATCLEAN, GPRMAKE, GPBUILD, GPRCLEAN
362   --  GNATMAKE, GPRMAKE, GPRMAKE:
363   --    set to True to skip bind and link steps (except when Bind_Only is
364   --    True).
365   --  GNATCLEAN, GPRCLEAN:
366   --    set to True to delete only the files produced by the compiler but not
367   --    the library files or the executable files.
368
369   Config_File : Boolean := True;
370   --  GNAT
371   --  Set to False to inhibit reading and processing of gnat.adc file
372
373   Config_File_Names : String_List_Access := null;
374   --  GNAT
375   --  Names of configuration pragmas files (given by switches -gnatec)
376
377   Configurable_Run_Time_Mode : Boolean := False;
378   --  GNAT, GNATBIND
379   --  Set True if the compiler is operating in configurable run-time mode.
380   --  This happens if the flag Targparm.Configurable_Run_TimeMode_On_Target
381   --  is set True, or if pragma No_Run_Time is used. See the spec of Rtsfind
382   --  for details on the handling of the latter pragma.
383
384   Constant_Condition_Warnings : Boolean := False;
385   --  GNAT
386   --  Set to True to activate warnings on constant conditions. Modified by
387   --  use of -gnatwc/C.
388
389   Create_Mapping_File : Boolean := False;
390   --  GNATMAKE, GPRMAKE
391   --  Set to True (-C switch) to indicate that the compiler will be invoked
392   --  with a mapping file (-gnatem compiler switch).
393
394   Debug_Pragmas_Enabled : Boolean := False;
395   --  GNAT
396   --  Enable debug statements from pragma Debug
397
398   Debug_Pragmas_Disabled : Boolean := False;
399   --  GNAT
400   --  Debug pragmas completely disabled (no semantic checking)
401
402   subtype Debug_Level_Value is Nat range 0 .. 3;
403   Debugger_Level : Debug_Level_Value := 0;
404   --  GNATBIND
405   --  The value given to the -g parameter. The default value for -g with
406   --  no value is 2. This is usually ignored by GNATBIND, except in the
407   --  VMS version where it is passed as an argument to __gnat_initialize
408   --  to trigger the activation of the remote debugging interface.
409   --  Is this still true ???
410
411   Debug_Generated_Code : Boolean := False;
412   --  GNAT
413   --  Set True (-gnatD switch) to debug generated expanded code instead
414   --  of the original source code. Causes debugging information to be
415   --  written with respect to the generated code file that is written.
416
417   Default_Exit_Status : Int := 0;
418   --  GNATBIND
419   --  Set the default exit status value. Set by the -Xnnn switch for the
420   --  binder.
421
422   Default_Stack_Size : Int := -1;
423   --  GNATBIND
424   --  Set to default primary stack size in units of bytes. Set by
425   --  the -dnnn switch for the binder. A value of -1 indicates that no
426   --  default was set by the binder.
427
428   Default_Sec_Stack_Size : Int := -1;
429   --  GNATBIND
430   --  Set to default secondary stack size in units of bytes. Set by
431   --  the -Dnnn switch for the binder. A value of -1 indicates that no
432   --  default was set by the binder, and that the default should be the
433   --  initial value of System.Secondary_Stack.Default_Secondary_Stack_Size.
434
435   Default_Pool : Node_Id := Empty;
436   --  GNAT
437   --  Used to record the storage pool name (or null literal) that is the
438   --  argument of an applicable pragma Default_Storage_Pool.
439   --    Empty:       No pragma Default_Storage_Pool applies.
440   --    N_Null node: "pragma Default_Storage_Pool (null);" applies.
441   --    otherwise:   "pragma Default_Storage_Pool (X);" applies, and
442   --                 this points to the name X.
443   --  Push_Scope and Pop_Scope in Sem_Ch8 save and restore this value.
444
445   Detect_Blocking : Boolean := False;
446   --  GNAT
447   --  Set True to force the run time to raise Program_Error if calls to
448   --  potentially blocking operations are detected from protected actions.
449
450   Display_Compilation_Progress : Boolean := False;
451   --  GNATMAKE, GPRMAKE, GPRBUILD
452   --  Set True (-d switch) to display information on progress while compiling
453   --  files. Internal flag to be used in conjunction with an IDE (e.g GPS).
454
455   type Distribution_Stub_Mode_Type is
456   --  GNAT
457     (No_Stubs,
458      --  Normal mode, no generation/compilation of distribution stubs
459
460      Generate_Receiver_Stub_Body,
461      --  The unit being compiled is the RCI body, and the compiler will
462      --  generate the body for the receiver stubs and compile it.
463
464      Generate_Caller_Stub_Body);
465      --  The unit being compiled is the RCI spec, and the compiler will
466      --  generate the body for the caller stubs and compile it.
467
468   Distribution_Stub_Mode : Distribution_Stub_Mode_Type := No_Stubs;
469   --  GNAT
470   --  This enumeration variable indicates the five states of distribution
471   --  annex stub generation/compilation.
472
473   Do_Not_Execute : Boolean := False;
474   --  GNATMAKE
475   --  Set to True if no actual compilations should be undertaken.
476
477   Dump_Source_Text : Boolean := False;
478   --  GNAT
479   --  Set to True (by -gnatL) to dump source text intermingled with generated
480   --  code. Effective only if either of Debug/Print_Generated_Code is true.
481
482   Dynamic_Elaboration_Checks : Boolean := False;
483   --  GNAT
484   --  Set True for dynamic elaboration checking mode, as set by the -gnatE
485   --  switch or by the use of pragma Elaboration_Checks (Dynamic).
486
487   Dynamic_Stack_Measurement : Boolean := False;
488   --  GNATBIND
489   --  Set True to enable dynamic stack measurement (-u flag for gnatbind)
490
491   Dynamic_Stack_Measurement_Array_Size : Nat := 100;
492   --  GNATBIND
493   --  Number of measurements we want to store during dynamic stack analysis.
494   --  When the buffer is full, non-storable results will be output on the fly.
495   --  The value is relevant only if Dynamic_Stack_Measurement is set. Set
496   --  by processing of -u flag for gnatbind.
497
498   Elab_Dependency_Output : Boolean := False;
499   --  GNATBIND
500   --  Set to True to output complete list of elaboration constraints
501
502   Elab_Order_Output : Boolean := False;
503   --  GNATBIND
504   --  Set to True to output chosen elaboration order
505
506   Elab_Warnings : Boolean := False;
507   --  GNAT
508   --  Set to True to generate full elaboration warnings (-gnatwl)
509
510   Error_Msg_Line_Length : Nat := 0;
511   --  GNAT
512   --  Records the error message line length limit. If this is set to zero,
513   --  then we get the old style behavior, in which each call to the error
514   --  message routines generates one line of output as a separate message.
515   --  If it is set to a non-zero value, then continuation lines are folded
516   --  to make a single long message, and then this message is split up into
517   --  multiple lines not exceeding the specified length. Set by -gnatj=nn.
518
519   Exception_Handler_Encountered : Boolean := False;
520   --  GNAT
521   --  This flag is set true if the parser encounters an exception handler.
522   --  It is used to set Warn_On_Exception_Propagation True if the restriction
523   --  No_Exception_Propagation is set.
524
525   Exception_Extra_Info : Boolean := False;
526   --  GNAT
527   --  True when switch -gnateE is used. When True, generate extra information
528   --  associated with exception messages (in particular range and index
529   --  checks).
530
531   Exception_Locations_Suppressed : Boolean := False;
532   --  GNAT
533   --  Set to True if a Suppress_Exception_Locations configuration pragma is
534   --  currently active.
535
536   type Exception_Mechanism_Type is
537   --  Determines the handling of exceptions. See Exp_Ch11 for details
538   --
539     (Front_End_Setjmp_Longjmp_Exceptions,
540      --  Exceptions use setjmp/longjmp generated explicitly by the front end
541      --  (this includes gigi or other equivalent parts of the code generator).
542      --  AT END handlers are converted into exception handlers by the front
543      --  end in this mode.
544
545      Back_End_Exceptions);
546      --  Exceptions are handled by the back end. The front end simply
547      --  generates the handlers as they appear in the source, and AT END
548      --  handlers are left untouched (they are not converted into exception
549      --  handlers when operating in this mode.
550   pragma Convention (C, Exception_Mechanism_Type);
551
552   Exception_Mechanism : Exception_Mechanism_Type :=
553                           Front_End_Setjmp_Longjmp_Exceptions;
554   --  GNAT
555   --  Set to the appropriate value depending on the default as given in
556   --  system.ads (ZCX_By_Default). The C convention is there to make this
557   --  variable accessible to gigi.
558
559   Exception_Tracebacks : Boolean := False;
560   --  GNATBIND
561   --  Set to True to store tracebacks in exception occurrences (-E)
562
563   Extensions_Allowed : Boolean := False;
564   --  GNAT
565   --  Set to True by switch -gnatX if GNAT specific language extensions
566   --  are allowed. Currently there are no such defined extensions.
567
568   type External_Casing_Type is (
569     As_Is,       -- External names cased as they appear in the Ada source
570     Uppercase,   -- External names forced to all uppercase letters
571     Lowercase);  -- External names forced to all lowercase letters
572
573   External_Name_Imp_Casing : External_Casing_Type := Lowercase;
574   --  GNAT
575   --  The setting of this flag determines the casing of external names
576   --  when the name is implicitly derived from an entity name (i.e. either
577   --  no explicit External_Name or Link_Name argument is used, or, in the
578   --  case of extended DEC pragmas, the external name is given using an
579   --  identifier. The As_Is setting is not permitted here (since this would
580   --  create Ada source programs that were case sensitive).
581
582   External_Name_Exp_Casing : External_Casing_Type := As_Is;
583   --  GNAT
584   --  The setting of this flag determines the casing of an external name
585   --  specified explicitly with a string literal. As_Is means the string
586   --  literal is used as given with no modification to the casing. If
587   --  Lowercase or Uppercase is set, then the string is forced to all
588   --  lowercase or all uppercase letters as appropriate. Note that this
589   --  setting has no effect if the external name is given using an identifier
590   --  in the case of extended DEC import/export pragmas (in this case the
591   --  casing is controlled by External_Name_Imp_Casing), and also has no
592   --  effect if an explicit Link_Name is supplied (a link name is always
593   --  used exactly as given).
594
595   External_Unit_Compilation_Allowed : Boolean := False;
596   --  GNATMAKE
597   --  When True (set by gnatmake switch -x), allow compilation of sources
598   --  that are not part of any project file.
599
600   Fast_Math : Boolean := False;
601   --  GNAT
602   --  Indicates the current setting of Fast_Math mode, as set by the use
603   --  of a Fast_Math pragma (set on by Fast_Math (On)).
604
605   Float_Format : Character := ' ';
606   --  GNAT
607   --  A non-blank value indicates that a Float_Format pragma has been
608   --  processed, in which case this variable is set to 'I' for IEEE or
609   --  to 'V' for VAX. The setting of 'V' is only possible on OpenVMS
610   --  versions of GNAT.
611
612   Float_Format_Long : Character := ' ';
613   --  GNAT
614   --  A non-blank value indicates that a Long_Float pragma has been
615   --  processed (this pragma is recognized only in OpenVMS versions
616   --  of GNAT), in which case this variable is set to D or G for
617   --  D_Float or G_Float.
618
619   Force_ALI_Tree_File : Boolean := False;
620   --  GNAT
621   --  Force generation of ALI file even if errors are encountered.
622   --  Also forces generation of tree file if -gnatt is also set.
623
624   Disable_ALI_File : Boolean := False;
625   --  GNAT
626   --  Disable generation of ALI file
627
628   Force_Checking_Of_Elaboration_Flags : Boolean := False;
629   --  GNATBIND
630   --  True if binding with forced checking of the elaboration flags
631   --  (-F switch set).
632
633   Force_Compilations : Boolean := False;
634   --  GNATMAKE, GPRMAKE, GPRBUILD
635   --  Set to force recompilations even when the objects are up-to-date.
636
637   Full_Path_Name_For_Brief_Errors : Boolean := False;
638   --  PROJECT MANAGER
639   --  When True, in Brief_Output mode, each error message line
640   --  will start with the full path name of the source.
641   --  When False, only the file name without directory information
642   --  is used.
643
644   Full_List : Boolean := False;
645   --  GNAT
646   --  Set True to generate full source listing with embedded errors
647
648   Full_List_File_Name : String_Ptr := null;
649   --  GNAT
650   --  Set to file name to generate full source listing to named file (or if
651   --  the name is of the form .xxx, then to name.xxx where name is the source
652   --  file name with extension stripped.
653
654   Generate_Processed_File : Boolean := False;
655   --  GNAT
656   --  True when switch -gnateG is used. When True, create in a file
657   --  <source>.prep, if the source is preprocessed.
658
659   Generate_SCO : Boolean := False;
660   --  GNAT
661   --  True when switch -fdump-scos (or -gnateS) is used. When True, Source
662   --  Coverage Obligation (SCO) information is generated and output in the ALI
663   --  file. See unit Par_SCO for full details.
664
665   Generate_SCO_Instance_Table : Boolean := False;
666   --  GNAT
667   --  True when switch -fdebug-instances is used. When True, a table of
668   --  instances is included in SCOs.
669
670   Generate_Target_Dependent_Info : Boolean := False;
671   --  GNAT
672   --  When true (-gnatet switch used). True if target dependent info is to be
673   --  generated in the ali file.
674
675   Generating_Code : Boolean := False;
676   --  GNAT
677   --  True if the frontend finished its work and has called the backend to
678   --  process the tree and generate the object file.
679
680   Global_Discard_Names : Boolean := False;
681   --  GNAT, GNATBIND
682   --  True if a pragma Discard_Names appeared as a configuration pragma for
683   --  the current compilation unit.
684
685   GNAT_Mode : Boolean := False;
686   --  GNAT
687   --  True if compiling in GNAT system mode (-gnatg switch)
688
689   Heap_Size : Nat := 0;
690   --  GNATBIND
691   --  Heap size for memory allocations. Valid values are 32 and 64. Only
692   --  available on VMS.
693
694   Identifier_Character_Set : Character;
695   --  GNAT
696   --  This variable indicates the character set to be used for identifiers.
697   --  The possible settings are:
698   --    '1'  Latin-5 (ISO-8859-1)
699   --    '2'  Latin-5 (ISO-8859-2)
700   --    '3'  Latin-5 (ISO-8859-3)
701   --    '4'  Latin-5 (ISO-8859-4)
702   --    '5'  Latin-5 (ISO-8859-5, Cyrillic)
703   --    '9'  Latin-5 (ISO-8859-9)
704   --    'p'  PC (US, IBM page 437)
705   --    '8'  PC (European, IBM page 850)
706   --    'f'  Full upper set (all distinct)
707   --    'n'  No upper characters (Ada 83 rules)
708   --    'w'  Latin-1 plus wide characters allowed in identifiers
709   --
710   --  The setting affects the set of letters allowed in identifiers and the
711   --  upper/lower case equivalences. It does not affect the interpretation of
712   --  character and string literals, which are always stored using the actual
713   --  coding in the source program. This variable is initialized to the
714   --  default value appropriate to the system (in Osint.Initialize), and then
715   --  reset if a command line switch is used to change the setting.
716
717   Ignore_Rep_Clauses : Boolean := False;
718   --  GNAT
719   --  Set True to ignore all representation clauses. Useful when compiling
720   --  code from foreign compilers for checking or ASIS purposes. Can be
721   --  set True by use of -gnatI.
722
723   Ignore_Style_Checks_Pragmas : Boolean := False;
724   --  GNAT
725   --  Set True to ignore all Style_Checks pragmas. Can be set True by use
726   --  of -gnateY.
727
728   Implementation_Unit_Warnings : Boolean := True;
729   --  GNAT
730   --  Set True to active warnings for use of implementation internal units.
731   --  Modified by use of -gnatwi/-gnatwI.
732
733   Implicit_Packing : Boolean := False;
734   --  GNAT
735   --  If set True, then a Size attribute clause on an array is allowed to
736   --  cause implicit packing instead of generating an error message. Set by
737   --  use of pragma Implicit_Packing.
738
739   Ineffective_Inline_Warnings : Boolean := False;
740   --  GNAT
741   --  Set True to activate warnings if front-end inlining (-gnatN) is not
742   --  able to actually inline a particular call (or all calls). Can be
743   --  controlled by use of -gnatwp/-gnatwP.
744
745   Init_Or_Norm_Scalars : Boolean := False;
746   --  GNAT, GANTBIND
747   --  Set True if a pragma Initialize_Scalars applies to the current unit.
748   --  Also set True if a pragma Normalize_Scalars applies.
749
750   Initialize_Scalars : Boolean := False;
751   --  GNAT
752   --  Set True if a pragma Initialize_Scalars applies to the current unit.
753   --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
754
755   Initialize_Scalars_Mode1 : Character := 'I';
756   Initialize_Scalars_Mode2 : Character := 'N';
757   --  GNATBIND
758   --  Set to two characters from -S switch (IN/LO/HI/EV/xx). The default
759   --  is IN (invalid values), used if no -S switch is used.
760
761   Inline_Active : Boolean := False;
762   --  GNAT
763   --  Set True to activate pragma Inline processing across modules. Default
764   --  for now is not to inline across module boundaries.
765
766   Inline_Level : Nat := 0;
767   --  GNAT
768   --  Set to indicate the inlining level: 0 means that an appropriate value is
769   --  to be computed by the compiler based on the optimization level (-gnatn),
770   --  1 is for moderate inlining across modules (-gnatn1) and 2 for full
771   --  inlining across modules (-gnatn2).
772
773   Interface_Library_Unit : Boolean := False;
774   --  GNATBIND
775   --  Set to True to indicate that at least one ALI file is an interface ALI:
776   --  then elaboration flag checks are to be generated in the binder
777   --  generated file.
778
779   Generate_SCIL : Boolean := False;
780   --  GNAT
781   --  Set True to activate SCIL code generation.
782
783   Invalid_Value_Used : Boolean := False;
784   --  GNAT
785   --  Set True if a valid Invalid_Value attribute is encountered
786
787   Follow_Links_For_Files : Boolean := False;
788   --  PROJECT MANAGER
789   --  Set to True (-eL) to process the project files in trusted mode. If
790   --  Follow_Links is False, it is assumed that the project doesn't contain
791   --  any file duplicated through symbolic links (although the latter are
792   --  still valid if they point to a file which is outside of the project),
793   --  and that no directory has a name which is a valid source name.
794
795   Follow_Links_For_Dirs : Boolean := False;
796   --  PROJECT MANAGER
797   --  Set to True if directories can be links in this project, and therefore
798   --  additional system calls must be performed to ensure that we always see
799   --  the same full name for each directory.
800
801   Front_End_Inlining : Boolean := False;
802   --  GNAT
803   --  Set True to activate inlining by front-end expansion
804
805   Inline_Processing_Required : Boolean := False;
806   --  GNAT
807   --  Set True if inline processing is required. Inline processing is required
808   --  if an active Inline pragma is processed. The flag is set for a pragma
809   --  Inline or Inline_Always that is actually active.
810
811   In_Place_Mode : Boolean := False;
812   --  GNATMAKE
813   --  Set True to store ALI and object files in place i.e. in the object
814   --  directory if these files already exist or in the source directory
815   --  if not.
816
817   Keep_Going : Boolean := False;
818   --  GNATMAKE, GPRMAKE, GPRBUILD
819   --  When True signals to ignore compilation errors and keep processing
820   --  sources until there is no more work.
821
822   Keep_Temporary_Files : Boolean := False;
823   --  GNATCMD
824   --  When True the temporary files created by the GNAT driver are not
825   --  deleted. Set by switch -dn or qualifier /KEEP_TEMPORARY_FILES.
826
827   Leap_Seconds_Support : Boolean := False;
828   --  GNATBIND
829   --  Set to True to enable leap seconds support in Ada.Calendar and its
830   --  children.
831
832   Link_Only : Boolean := False;
833   --  GNATMAKE, GPRMAKE, GPRBUILD
834   --  Set to True to skip compile and bind steps (except when Bind_Only is
835   --  set to True).
836
837   List_Inherited_Aspects : Boolean := False;
838   --  GNAT
839   --  List inherited invariants, preconditions, and postconditions from
840   --  Invariant'Class, Pre'Class, and Post'Class aspects. Also list inherited
841   --  subtype predicates. Modified by use of -gnatw.l/.L.
842
843   List_Restrictions : Boolean := False;
844   --  GNATBIND
845   --  Set to True to list restrictions pragmas that could apply to partition
846
847   List_Units : Boolean := False;
848   --  GNAT
849   --  List units in the active library for a compilation (-gnatu switch)
850
851   List_Closure : Boolean := False;
852   --  GNATBIND
853   --  List all sources in the closure of a main (-R gnatbind switch)
854
855   List_Dependencies : Boolean := False;
856   --  GNATMAKE
857   --  When True gnatmake verifies that the objects are up to date and
858   --  outputs the list of object dependencies (-M switch).
859   --  Output depends if -a switch is used or not.
860   --  This list can be used directly in a Makefile.
861
862   List_Representation_Info : Int range 0 .. 3 := 0;
863   --  GNAT
864   --  Set non-zero by -gnatR switch to list representation information.
865   --  The settings are as follows:
866   --
867   --    0 = no listing of representation information (default as above)
868   --    1 = list rep info for user defined record and array types
869   --    2 = list rep info for all user defined types and objects
870   --    3 = like 2, but variable fields are decoded symbolically
871
872   List_Representation_Info_To_File : Boolean := False;
873   --  GNAT
874   --  Set true by -gnatRs switch. Causes information from -gnatR/1/2/3 to be
875   --  written to file.rep (where file is the name of the source file) instead
876   --  of stdout. For example, if file x.adb is compiled using -gnatR2s then
877   --  representation info is written to x.adb.ref.
878
879   List_Representation_Info_Mechanisms : Boolean := False;
880   --  GNAT
881   --  Set true by -gnatRm switch. Causes information on mechanisms to be
882   --  included in the representation output information.
883
884   List_Preprocessing_Symbols : Boolean := False;
885   --  GNAT, GNATPREP
886   --  Set to True if symbols for preprocessing a source are to be listed
887   --  before preprocessing occurs. Set to True by switch -s of gnatprep or
888   --  -s in preprocessing data file for the compiler.
889
890   type Create_Repinfo_File_Proc is access procedure (Src  : String);
891   type Write_Repinfo_Line_Proc  is access procedure (Info : String);
892   type Close_Repinfo_File_Proc  is access procedure;
893   --  Types used for procedure addresses below
894
895   Create_Repinfo_File_Access : Create_Repinfo_File_Proc := null;
896   Write_Repinfo_Line_Access  : Write_Repinfo_Line_Proc  := null;
897   Close_Repinfo_File_Access  : Close_Repinfo_File_Proc  := null;
898   --  GNAT
899   --  These three locations are left null when operating in non-compiler (e.g.
900   --  ASIS mode), but when operating in compiler mode, they are set to point
901   --  to the three corresponding procedures in Osint-C. The reason for this
902   --  slightly strange interface is to stop Repinfo from dragging in Osint in
903   --  ASIS mode, which would include lots of unwanted units in the ASIS build.
904
905   type Create_List_File_Proc is access procedure (S : String);
906   type Write_List_Info_Proc  is access procedure (S : String);
907   type Close_List_File_Proc  is access procedure;
908   --  Types used for procedure addresses below
909
910   Create_List_File_Access : Create_List_File_Proc := null;
911   Write_List_Info_Access  : Write_List_Info_Proc  := null;
912   Close_List_File_Access  : Close_List_File_Proc  := null;
913   --  GNAT
914   --  These three locations are left null when operating in non-compiler
915   --  (e.g. from the binder), but when operating in compiler mode, they are
916   --  set to point to the three corresponding procedures in Osint-C. The
917   --  reason for this slightly strange interface is to prevent Repinfo
918   --  from dragging in Osint-C in the binder, which would include unwanted
919   --  units in the binder.
920
921   Locking_Policy : Character := ' ';
922   --  GNAT, GNATBIND
923   --  Set to ' ' for the default case (no locking policy specified). Reset to
924   --  first character (uppercase) of locking policy name if a valid pragma
925   --  Locking_Policy is encountered.
926
927   Locking_Policy_Sloc : Source_Ptr := No_Location;
928   --  GNAT, GNATBIND
929   --  Remember location of previous Locking_Policy pragma. This is used for
930   --  inconsistency error messages. A value of System_Location is used if the
931   --  policy is set in package System.
932
933   Look_In_Primary_Dir : Boolean := True;
934   --  GNAT, GNATBIND, GNATMAKE, GNATCLEAN
935   --  Set to False if a -I- was present on the command line. When True we are
936   --  allowed to look in the primary directory to locate other source or
937   --  library files.
938
939   Make_Steps : Boolean := False;
940   --  GNATMAKE
941   --  Set to True when either Compile_Only, Bind_Only or Link_Only is
942   --  set to True.
943
944   Main_Index : Int := 0;
945   --  GNATMAKE
946   --  This is set to non-zero by gnatmake switch -eInnn to indicate that
947   --  the main program is the nnn unit in a multi-unit source file.
948
949   Mapping_File_Name : String_Ptr := null;
950   --  GNAT
951   --  File name of mapping between unit names, file names and path names.
952   --  (given by switch -gnatem)
953
954   Maximum_Messages : Int := 9999;
955   --  GNAT, GNATBIND
956   --  Maximum default number of errors before compilation is terminated, or in
957   --  the case of GNAT, maximum number of warnings before further warnings are
958   --  suppressed. Can be overridden by -gnatm (GNAT) or -m (GNATBIND) switch.
959
960   Maximum_File_Name_Length : Int;
961   --  GNAT, GNATBIND
962   --  Maximum number of characters allowed in a file name, not counting the
963   --  extension, as set by the appropriate switch. If no switch is given,
964   --  then this value is initialized by Osint to the appropriate value.
965
966   Maximum_Instantiations : Int := 8000;
967   --  GNAT
968   --  Maximum number of instantiations permitted (to stop runaway cases
969   --  of nested instantiations). These situations probably only occur in
970   --  specially concocted test cases. Can be modified by -gnateinn switch.
971
972   Maximum_Processes : Positive := 1;
973   --  GNATMAKE, GPRMAKE, GPRBUILD
974   --  Maximum number of processes that should be spawned to carry out
975   --  compilations.
976
977   Minimal_Recompilation : Boolean := False;
978   --  GNATMAKE
979   --  Set to True if minimal recompilation mode requested
980
981   Multiple_Unit_Index : Int;
982   --  GNAT
983   --  This is set non-zero if the current unit is being compiled in multiple
984   --  unit per file mode, meaning that the current unit is selected from the
985   --  sequence of units in the current source file, using the value stored
986   --  in this variable (e.g. 2 = select second unit in file). A value of
987   --  zero indicates that we are in normal (one unit per file) mode.
988
989   No_Deletion : Boolean := False;
990   --  GNATPREP
991   --  Set by preprocessor switch -a. Do not eliminate any source text. Implies
992   --  Undefined_Symbols_Are_False. Useful to perform a syntax check on all
993   --  branches of #if constructs.
994
995   No_Main_Subprogram : Boolean := False;
996   --  GNATMAKE, GNATBIND
997   --  Set to True if compilation/binding of a program without main
998   --  subprogram requested.
999
1000   No_Run_Time_Mode : Boolean := False;
1001   --  GNAT, GNATBIND
1002   --  This flag is set True if a No_Run_Time pragma is encountered. See
1003   --  spec of Rtsfind for a full description of handling of this pragma.
1004
1005   No_Split_Units : Boolean := False;
1006   --  GPRBUILD
1007   --  Set to True with switch --no-split-units. When True, unit sources, spec,
1008   --  body and subunits, must all be in the same project.This is checked after
1009   --  each compilation.
1010
1011   No_Stdinc : Boolean := False;
1012   --  GNAT, GNATBIND, GNATMAKE, GNATFIND, GNATXREF
1013   --  Set to True if no default source search dirs added to search list
1014
1015   No_Stdlib : Boolean := False;
1016   --  GNATMAKE, GNATBIND, GNATFIND, GNATXREF
1017   --  Set to True if no default library search dirs added to search list
1018
1019   No_Strict_Aliasing : Boolean := False;
1020   --  GNAT
1021   --  Set True if pragma No_Strict_Aliasing with no parameters encountered
1022
1023   Normalize_Scalars : Boolean := False;
1024   --  GNAT, GNATBIND
1025   --  Set True if a pragma Normalize_Scalars applies to the current unit.
1026   --  Note that Init_Or_Norm_Scalars is also set to True if this is True.
1027
1028   Object_Directory_Present : Boolean := False;
1029   --  GNATMAKE
1030   --  Set to True when an object directory is specified with option -D
1031
1032   Object_Path_File_Name : String_Ptr := null;
1033   --  GNAT2WHY
1034   --  Path of the temporary file that contains a list of object directories
1035   --  passed by -gnateO=<obj_path_file>.
1036
1037   One_Compilation_Per_Obj_Dir : Boolean := False;
1038   --  GNATMAKE, GPRBUILD
1039   --  Set to True with switch --single-compile-per-obj-dir. When True, there
1040   --  cannot be simultaneous compilations with the object files in the same
1041   --  object directory, if project files are used.
1042
1043   type Operating_Mode_Type is (Check_Syntax, Check_Semantics, Generate_Code);
1044   Operating_Mode : Operating_Mode_Type := Generate_Code;
1045   --  GNAT
1046   --  Indicates the operating mode of the compiler. The default is generate
1047   --  code, which runs the parser, semantics and backend. Switches can be
1048   --  used to set syntax checking only mode, or syntax and semantics checking
1049   --  only mode. Operating_Mode can also be modified as a result of detecting
1050   --  errors during the compilation process. In particular if any serious
1051   --  error is detected then this flag is reset from Generate_Code to
1052   --  Check_Semantics after generating an error message.
1053
1054   Optimize_Alignment : Character := 'O';
1055   --  Setting of Optimize_Alignment, set to T/S/O for time/space/off. Can
1056   --  be modified by use of pragma Optimize_Alignment.
1057
1058   Optimize_Alignment_Local : Boolean := False;
1059   --  Set True if Optimize_Alignment mode is set by a local configuration
1060   --  pragma that overrides the gnat.adc (or other configuration file) default
1061   --  so that the unit is not dependent on the default setting. Also always
1062   --  set True for internal units, since these always have a default setting
1063   --  of Optimize_Alignment (Off) that is enforced (essentially equivalent to
1064   --  them all having such an explicit pragma in each unit).
1065
1066   Original_Operating_Mode : Operating_Mode_Type := Generate_Code;
1067   --  GNAT
1068   --  Indicates the original operating mode of the compiler as set by compiler
1069   --  options. This is identical to Operating_Mode except that this is not
1070   --  affected by errors.
1071
1072   Optimization_Level : Int;
1073   pragma Import (C, Optimization_Level, "optimize");
1074   --  Constant reflecting the optimization level (0,1,2,3 for -O0,-O1,-O2,-O3)
1075   --  See jmissing.c and aamissing.c for definitions for dotnet/jgnat and
1076   --  GNAAMP back ends.
1077
1078   Optimize_Size : Int;
1079   pragma Import (C, Optimize_Size, "optimize_size");
1080   --  Constant reflecting setting of -Os (optimize for size). Set to nonzero
1081   --  in -Os mode and set to zero otherwise. See jmissing.c and aamissing.c
1082   --  for definitions of "optimize_size" for dotnet/jgnat and GNAAMP backends
1083
1084   Output_File_Name_Present : Boolean := False;
1085   --  GNATBIND, GNAT, GNATMAKE, GPRMAKE
1086   --  Set to True when the output C file name is given with option -o for
1087   --  GNATBIND, when the object file name is given with option -gnatO for GNAT
1088   --  or when the executable is given with option -o for GNATMAKE or GPRMAKE.
1089
1090   Output_Linker_Option_List : Boolean := False;
1091   --  GNATBIND
1092   --  True if output of list of linker options is requested (-K switch set)
1093
1094   Output_ALI_List   : Boolean := False;
1095   ALI_List_Filename : String_Ptr;
1096   --  GNATBIND
1097   --  True if output of list of ALIs is requested (-A switch set). List is
1098   --  output under the given filename, or standard output if not specified.
1099
1100   Output_Object_List   : Boolean := False;
1101   Object_List_Filename : String_Ptr;
1102   --  GNATBIND
1103   --  True if output of list of objects is requested (-O switch set). List is
1104   --  output under the given filename, or standard output if not specified.
1105
1106   Partition_Elaboration_Policy : Character := ' ';
1107   --  GNAT, GNATBIND
1108   --  Set to ' ' for the default case (no elaboration policy specified). Reset
1109   --  to first character (uppercase) of locking policy name if a valid pragma
1110   --  Partition_Elaboration_Policy is encountered.
1111
1112   Partition_Elaboration_Policy_Sloc : Source_Ptr := No_Location;
1113   --  GNAT, GNATBIND
1114   --  Remember location of previous Partition_Elaboration_Policy pragma. This
1115   --  is used for inconsistency error messages. A value of System_Location is
1116   --  used if the policy is set in package System.
1117
1118   Persistent_BSS_Mode : Boolean := False;
1119   --  GNAT
1120   --  True if a Persistent_BSS configuration pragma is in effect, causing
1121   --  potentially persistent data to be placed in the persistent_bss section.
1122
1123   Pessimistic_Elab_Order : Boolean := False;
1124   --  GNATBIND
1125   --  True if pessimistic elaboration order is to be chosen (-p switch set)
1126
1127   Polling_Required : Boolean := False;
1128   --  GNAT
1129   --  Set to True if polling for asynchronous abort is enabled by using
1130   --  the -gnatP option for GNAT.
1131
1132   Preprocessing_Data_File : String_Ptr := null;
1133   --  GNAT
1134   --  Set by switch -gnatep=. The file name of the preprocessing data file.
1135
1136   Preprocessing_Symbol_Defs : String_List_Access := new String_List (1 .. 4);
1137   --  An extensible array to temporarily stores symbol definitions specified
1138   --  on the command line with -gnateD switches.
1139   --  What is this magic constant 4 ???
1140   --  What is extensible about this fixed length array ???
1141
1142   Preprocessing_Symbol_Last : Natural := 0;
1143   --  Index of last symbol definition in array Symbol_Definitions
1144
1145   Print_Generated_Code : Boolean := False;
1146   --  GNAT
1147   --  Set to True to enable output of generated code in source form. This
1148   --  flag is set by the -gnatG switch.
1149
1150   Print_Standard : Boolean := False;
1151   --  GNAT
1152   --  Set to true to enable printing of package standard in source form.
1153   --  This flag is set by the -gnatS switch
1154
1155   Propagate_Exceptions : Boolean := False;
1156   --  GNAT
1157   --  Indicates if subprogram descriptor exception tables should be
1158   --  built for imported subprograms. Set True if a Propagate_Exceptions
1159   --  pragma applies to the extended main unit.
1160
1161   type Usage is (Unknown, Not_In_Use, In_Use);
1162   Project_File_In_Use : Usage := Unknown;
1163   --  GNAT
1164   --  Indicates if a project file is used or not. Set to In_Use by the first
1165   --  SFNP pragma.
1166
1167   Queuing_Policy : Character := ' ';
1168   --  GNAT, GNATBIND
1169   --  Set to ' ' for the default case (no queuing policy specified). Reset to
1170   --  first character (uppercase) of locking policy name if a valid
1171   --  Queuing_Policy pragma is encountered.
1172
1173   Queuing_Policy_Sloc : Source_Ptr := No_Location;
1174   --  GNAT, GNATBIND
1175   --  Remember location of previous Queuing_Policy pragma. This is used for
1176   --  inconsistency error messages. A value of System_Location is used if the
1177   --  policy is set in package System.
1178
1179   Quiet_Output : Boolean := False;
1180   --  GNATMAKE, GNATCLEAN, GPRMAKE, GPRBUILD, GPRCLEAN
1181   --  Set to True if the tool should not have any output if there are no
1182   --  errors or warnings.
1183
1184   Overriding_Renamings : Boolean := False;
1185   --  GNAT
1186   --  Set to True to enable compatibility mode with Rational compiler, and
1187   --  to accept renamings of implicit operations in their own scope.
1188
1189   Replace_In_Comments : Boolean := False;
1190   --  GNATPREP
1191   --  Set to True if -C switch used
1192
1193   RTS_Lib_Path_Name : String_Ptr := null;
1194   RTS_Src_Path_Name : String_Ptr := null;
1195   --  GNAT
1196   --  Set to the "adalib" and "adainclude" directories of the run time
1197   --  specified by --RTS=.
1198
1199   RTS_Switch : Boolean := False;
1200   --  GNAT, GNATMAKE, GNATBIND, GNATLS, GNATFIND, GNATXREF
1201   --  Set to True when the --RTS switch is set
1202
1203   Run_Path_Option : Boolean := True;
1204   --  GNATMAKE, GNATLINK
1205   --  Set to False when no run_path_option should be issued to the linker
1206
1207   Search_Directory_Present : Boolean := False;
1208   --  GNAT
1209   --  Set to True when argument is -I. Reset to False when next argument, a
1210   --  search directory path is taken into account. Note that this is quite
1211   --  different from other switches in this section in that it is only set in
1212   --  a transitory manner as a result of scanning a -I switch with no file
1213   --  name, and if set, is an indication that the next argument is to be
1214   --  treated as a file name.
1215
1216   Sec_Stack_Used : Boolean := False;
1217   --  GNAT, GBATBIND
1218   --  Set True if generated code uses the System.Secondary_Stack package. For
1219   --  the binder, set if any unit uses the secondary stack package.
1220
1221   Setup_Projects : Boolean := False;
1222   --  GNAT DRIVER
1223   --  Set to True for GNAT SETUP: the Project Manager creates non existing
1224   --  object, library and exec directories.
1225
1226   Shared_Libgnat : Boolean;
1227   --  GNATBIND
1228   --  Set to True if a shared libgnat is requested by using the -shared option
1229   --  for GNATBIND and to False when using the -static option. The value of
1230   --  this flag is set by Gnatbind.Scan_Bind_Arg.
1231
1232   Short_Circuit_And_Or : Boolean := False;
1233   --  GNAT
1234   --  Set True if a pragma Short_Circuit_And_Or applies to the current unit.
1235
1236   Short_Descriptors : Boolean := False;
1237   --  GNAT
1238   --  Set True if a pragma Short_Descriptors applies to the current unit.
1239
1240   Special_Exception_Package_Used : Boolean := False;
1241   --  GNAT
1242   --  Set to True if either of the unit GNAT.Most_Recent_Exception or
1243   --  GNAT.Exception_Traces is with'ed. Used to inhibit transformation of
1244   --  local raise statements into gotos in the presence of either package.
1245
1246   Sprint_Line_Limit : Nat := 72;
1247   --  GNAT
1248   --  Limit values for chopping long lines in Sprint output, can be reset
1249   --  by use of NNN parameter with -gnatG or -gnatD switches.
1250
1251   Stack_Checking_Enabled : Boolean;
1252   --  GNAT
1253   --  Set to indicate if -fstack-check switch is set for the compilation. True
1254   --  means that the switch is set, so that stack checking is enabled. False
1255   --  means that the switch is not set (no stack checking). This value is
1256   --  obtained from the external imported value flag_stack_check in the gcc
1257   --  backend (see Frontend) and may be referenced throughout the compilation
1258   --  phases.
1259
1260   Style_Check : Boolean := False;
1261   --  GNAT
1262   --  Set True to perform style checks. Activates checks carried out in
1263   --  package Style (see body of this package for details of checks). This
1264   --  flag is set True by either the -gnatg or -gnaty switches.
1265
1266   Suppress_All_Inlining : Boolean := False;
1267   --  GNAT
1268   --  Set by -fno-inline. Suppresses all inlining, both front end and back end
1269   --  regardless of any other switches that are set.
1270
1271   Suppress_Control_Flow_Optimizations : Boolean := False;
1272   --  GNAT
1273   --  Set by -fpreserve-control-flow. Suppresses control flow optimizations
1274   --  that interfere with coverage analysis based on the object code.
1275
1276   System_Extend_Pragma_Arg : Node_Id := Empty;
1277   --  GNAT
1278   --  Set non-empty if and only if a correct Extend_System pragma was present
1279   --  in which case it points to the argument of the pragma, and the name can
1280   --  be located as Chars (Expression (System_Extend_Pragma_Arg)).
1281
1282   System_Extend_Unit : Node_Id := Empty;
1283   --  GNAT
1284   --  This is set to Empty if GNAT_Mode is set, since pragma Extend_System
1285   --  is never appropriate in GNAT_Mode (and causes troubles, including
1286   --  bogus circularities, if we try to compile the run-time library with
1287   --  a System extension). If GNAT_Mode is not set, then System_Extend_Unit
1288   --  is a copy of the value set in System_Extend_Pragma_Arg.
1289
1290   Subunits_Missing : Boolean := False;
1291   --  GNAT
1292   --  This flag is set true if missing subunits are detected with code
1293   --  generation active. This causes code generation to be skipped.
1294
1295   Suppress_Checks : Boolean := False;
1296   --  GNAT
1297   --  Set to True if -gnatp (suppress all checks) switch present.
1298
1299   Suppress_Options : Suppress_Record;
1300   --  GNAT
1301   --  Indicates outer level setting of check suppression. This initializes
1302   --  the settings of the outer scope level in any unit compiled. This is
1303   --  initialized by Osint.Initialize, and further initialized by the
1304   --  Adjust_Global_Switches flag in Gnat1drv.
1305
1306   Suppress_Back_Annotation : Boolean := False;
1307   --  GNAT
1308   --  This flag is set True if back annotation of representation information
1309   --  is to be suppressed. This is set if neither -gnatt or -gnatR0-3 is set.
1310   --  This avoids unnecessary time being spent on back annotation.
1311
1312   Table_Factor : Int := 1;
1313   --  GNAT
1314   --  Factor by which all initial table sizes set in Alloc are multiplied.
1315   --  Used in Table to calculate initial table sizes (the initial table size
1316   --  is the value in Alloc, used as the Table_Initial parameter value,
1317   --  multiplied by the factor given here. The default value is used if no
1318   --  -gnatT switch appears.
1319
1320   Tagged_Type_Expansion : Boolean := True;
1321   --  GNAT
1322   --  Set True if tagged types and interfaces should be expanded by the
1323   --  front-end. If False, the original tree is left unexpanded for tagged
1324   --  types and dispatching calls, assuming the underlying target supports
1325   --  it (e.g. in the JVM case).
1326
1327   Task_Dispatching_Policy : Character := ' ';
1328   --  GNAT, GNATBIND
1329   --  Set to ' ' for the default case (no task dispatching policy specified).
1330   --  Reset to first character (uppercase) of task dispatching policy name
1331   --  if a valid Task_Dispatching_Policy pragma is encountered.
1332
1333   Task_Dispatching_Policy_Sloc : Source_Ptr := No_Location;
1334   --  GNAT, GNATBIND
1335   --  Remember location of previous Task_Dispatching_Policy pragma. This is
1336   --  used for inconsistency error messages. A value of System_Location is
1337   --  used if the policy is set in package System.
1338
1339   Tasking_Used : Boolean := False;
1340   --  Set True if any tasking construct is encountered. Used to activate the
1341   --  output of the Q, L and T lines in ALI files.
1342
1343   Time_Slice_Set : Boolean := False;
1344   --  GNATBIND
1345   --  Set True if a pragma Time_Slice is processed in the main unit, or
1346   --  if the -gnatTnn switch is present to set a time slice value.
1347
1348   Time_Slice_Value : Nat;
1349   --  GNATBIND
1350   --  Time slice value. Valid only if Time_Slice_Set is True, i.e. if
1351   --  Time_Slice pragma has been processed. Set to the time slice value in
1352   --  microseconds. Negative values are stored as zero, and the value is not
1353   --  larger than 1_000_000_000 (1000 seconds). Values larger than this are
1354   --  reset to this maximum. This can also be set with the -gnatTnn switch.
1355
1356   Tolerate_Consistency_Errors : Boolean := False;
1357   --  GNATBIND
1358   --  Tolerate time stamp and other consistency errors. If this flag is set to
1359   --  True (-t), then inconsistencies result in warnings rather than errors.
1360
1361   Treat_Categorization_Errors_As_Warnings : Boolean := False;
1362   --  Normally categorization errors are true illegalities. If this switch
1363   --  is set, then such errors result in warning messages rather than error
1364   --  messages. Set True by -gnateP (P for Pure/Preelaborate).
1365
1366   Treat_Restrictions_As_Warnings : Boolean := False;
1367   --  GNAT
1368   --  Set True to treat pragma Restrictions as Restriction_Warnings. Set by
1369   --  -gnatr switch.
1370
1371   Tree_Output : Boolean := False;
1372   --  GNAT
1373   --  Set to True (-gnatt) to generate output tree file
1374
1375   True_VMS_Target : Boolean := False;
1376   --  Set True if we are on a VMS target. The setting of this flag reflects
1377   --  the true state of the compile, unlike Targparm.OpenVMS_On_Target which
1378   --  can also be true when debug flag m is set (-gnatdm). This is used in the
1379   --  few cases where we do NOT want -gnatdm to trigger the VMS behavior.
1380
1381   Try_Semantics : Boolean := False;
1382   --  GNAT
1383   --  Flag set to force attempt at semantic analysis, even if parser errors
1384   --  occur. This will probably cause blowups at this stage in the game. On
1385   --  the other hand, most such blowups will be caught cleanly and simply
1386   --  say compilation abandoned. This flag is set to True by -gnatq or -gnatQ.
1387
1388   Unchecked_Shared_Lib_Imports : Boolean := False;
1389   --  GPRBUILD
1390   --  Set to True when shared library projects are allowed to import projects
1391   --  that are not shared library projects. Set by switch
1392   --  --unchecked-shared-lib-imports.
1393
1394   Undefined_Symbols_Are_False : Boolean := False;
1395   --  GNAT, GNATPREP
1396   --  Set to True by switch -u of gnatprep or -u in the preprocessing data
1397   --  file for the compiler. Indicates that while preprocessing sources,
1398   --  symbols that are not defined have the value FALSE.
1399
1400   Unique_Error_Tag : Boolean := Tag_Errors;
1401   --  GNAT
1402   --  Indicates if error messages are to be prefixed by the string error:
1403   --  Initialized from Tag_Errors, can be forced on with the -gnatU switch.
1404
1405   Universal_Addressing_On_AAMP : Boolean := False;
1406   --  GNAAMP
1407   --  Indicates if library-level objects should be accessed and updated using
1408   --  universal addressing instructions on the AAMP architecture. This flag is
1409   --  set to True when pragma Universal_Data is given as a configuration
1410   --  pragma.
1411
1412   Unreserve_All_Interrupts : Boolean := False;
1413   --  GNAT, GNATBIND
1414   --  Normally set False, set True if a valid Unreserve_All_Interrupts pragma
1415   --  appears anywhere in the main unit for GNAT, or if any ALI file has the
1416   --  corresponding attribute set in GNATBIND.
1417
1418   Upper_Half_Encoding : Boolean := False;
1419   --  GNAT, GNATBIND
1420   --  Normally set False, indicating that upper half ISO 8859-1 characters are
1421   --  used in the normal way to represent themselves. If the wide character
1422   --  encoding method uses the upper bit for this encoding, then this flag is
1423   --  set True, and upper half characters in the source indicate the start of
1424   --  a wide character sequence. Set by -gnatW or -W switches.
1425
1426   Use_Include_Path_File : Boolean := False;
1427   --  GNATMAKE, GPRBUILD
1428   --  When True, create a source search path file, even when a mapping file
1429   --  is used.
1430
1431   Usage_Requested : Boolean := False;
1432   --  GNAT, GNATBIND, GNATMAKE
1433   --  Set to True if -h (-gnath for the compiler) switch encountered
1434   --  requesting usage information
1435
1436   Use_Expression_With_Actions : Boolean;
1437   --  The N_Expression_With_Actions node has been introduced relatively
1438   --  recently, and not all back ends are prepared to handle it yet. So
1439   --  we use this flag to suppress its use during a transitional period.
1440   --  Currently the default is False for all cases (set in gnat1drv).
1441   --  The default can be modified using -gnatd.X/-gnatd.Y.
1442
1443   Use_Pragma_Linker_Constructor : Boolean := False;
1444   --  GNATBIND
1445   --  True if pragma Linker_Constructor applies to adainit
1446
1447   Use_VADS_Size : Boolean := False;
1448   --  GNAT
1449   --  Set to True if a valid pragma Use_VADS_Size is processed
1450
1451   Validity_Checks_On  : Boolean := True;
1452   --  GNAT
1453   --  This flag determines if validity checking is on or off. The initial
1454   --  state is on, and the required default validity checks are active. The
1455   --  actual set of checks that is performed if Validity_Checks_On is set is
1456   --  defined by the switches in package Validsw. The Validity_Checks_On flag
1457   --  is controlled by pragma Validity_Checks (On | Off), and also some
1458   --  generated compiler code (typically code that has to do with validity
1459   --  check generation) is compiled with this flag set to False. This flag is
1460   --  set to False by the -gnatp switch.
1461
1462   Verbose_Mode : Boolean := False;
1463   --  GNAT, GNATBIND, GNATMAKE, GNATLINK, GNATLS, GNATNAME, GNATCLEAN,
1464   --  GPRMAKE, GPRBUILD, GPRCLEAN
1465   --  Set to True to get verbose mode (full error message text and location
1466   --  information sent to standard output, also header, copyright and summary)
1467
1468   type Verbosity_Level_Type is (None, Low, Medium, High);
1469   pragma Ordered (Verbosity_Level_Type);
1470   Verbosity_Level : Verbosity_Level_Type := High;
1471   --  GNATMAKE, GPRMAKE
1472   --  Modified by gnatmake or gprmake switches -v, -vl, -vm, -vh. Indicates
1473   --  the level of verbosity of informational messages:
1474   --
1475   --  In Low Verbosity, the reasons why a source is recompiled, the name
1476   --  of the executable and the reason it must be rebuilt is output.
1477   --
1478   --  In Medium Verbosity, additional lines are output for each ALI file
1479   --  that is checked.
1480   --
1481   --  In High Verbosity, additional lines are output when the ALI file
1482   --  is part of an Ada library, is read-only or is part of the runtime.
1483
1484   Warn_On_Ada_2005_Compatibility : Boolean := True;
1485   --  GNAT
1486   --  Set to True to generate all warnings on Ada 2005 compatibility issues,
1487   --  including warnings on Ada 2005 obsolescent features used in Ada 2005
1488   --  mode. Set by default, modified by use of -gnatwy/Y.
1489
1490   Warn_On_Ada_2012_Compatibility : Boolean := True;
1491   --  GNAT
1492   --  Set to True to generate all warnings on Ada 2012 compatibility issues,
1493   --  including warnings on Ada 2012 obsolescent features used in Ada 2012
1494   --  mode. Modified by use of -gnatwy/Y.
1495
1496   Warn_On_All_Unread_Out_Parameters : Boolean := False;
1497   --  GNAT
1498   --  Set to True to generate warnings in all cases where a variable is
1499   --  modified by being passed as to an OUT formal, but the resulting value is
1500   --  never read. The default is that this warning is suppressed. Modified
1501   --  by use of gnatw.o/.O.
1502
1503   Warn_On_Assertion_Failure : Boolean := True;
1504   --  GNAT
1505   --  Set to True to activate warnings on assertions that can be determined
1506   --  at compile time will always fail. Modified by use of -gnatw.a/.A.
1507
1508   Warn_On_Assumed_Low_Bound : Boolean := True;
1509   --  GNAT
1510   --  Set to True to activate warnings for string parameters that are indexed
1511   --  with literals or S'Length, presumably assuming a lower bound of one.
1512   --  Modified by use of -gnatww/W.
1513
1514   Warn_On_Atomic_Synchronization : Boolean := False;
1515   --  GNAT
1516   --  Set to True to generate information messages for atomic synchronization.
1517   --  Modified by use of -gnatw.n/.N.
1518
1519   Warn_On_Bad_Fixed_Value : Boolean := False;
1520   --  GNAT
1521   --  Set to True to generate warnings for static fixed-point expression
1522   --  values that are not an exact multiple of the small value of the type.
1523   --  Odd by default, modified by use of -gnatwb/B.
1524
1525   Warn_On_Biased_Representation : Boolean := True;
1526   --  GNAT
1527   --  Set to True to generate warnings for size clauses, component clauses
1528   --  and component_size clauses that force biased representation. Modified
1529   --  by use of -gnatw.b/.B.
1530
1531   Warn_On_Constant : Boolean := False;
1532   --  GNAT
1533   --  Set to True to generate warnings for variables that could be declared
1534   --  as constants. Modified by use of -gnatwk/K.
1535
1536   Warn_On_Deleted_Code : Boolean := False;
1537   --  GNAT
1538   --  Set to True to generate warnings for code deleted by the front end
1539   --  for conditional statements whose outcome is known at compile time.
1540   --  Modified by use of -gnatwt/T.
1541
1542   Warn_On_Dereference : Boolean := False;
1543   --  GNAT
1544   --  Set to True to generate warnings for implicit dereferences for array
1545   --  indexing and record component access. Modified by use of -gnatwd/D.
1546
1547   Warn_On_Export_Import : Boolean := True;
1548   --  GNAT
1549   --  Set to True to generate warnings for suspicious use of export or
1550   --  import pragmas. Modified by use of -gnatwx/X.
1551
1552   Warn_On_Hiding : Boolean := False;
1553   --  GNAT
1554   --  Set to True to generate warnings if a declared entity hides another
1555   --  entity. The default is that this warning is suppressed. Modified by
1556   --  use of -gnatwh/H.
1557
1558   Warn_On_Modified_Unread : Boolean := False;
1559   --  GNAT
1560   --  Set to True to generate warnings if a variable is assigned but is never
1561   --  read. Also controls warnings for similar cases involving out parameters,
1562   --  but only if there is only one out parameter for the procedure involved.
1563   --  The default is that this warning is suppressed, modified by use of
1564   --  -gnatwm/M.
1565
1566   Warn_On_No_Value_Assigned : Boolean := True;
1567   --  GNAT
1568   --  Set to True to generate warnings if no value is ever assigned to a
1569   --  variable that is at least partially uninitialized. Set to false to
1570   --  suppress such warnings. The default is that such warnings are enabled.
1571   --  Modified by use of -gnatwv/V.
1572
1573   Warn_On_Non_Local_Exception : Boolean := False;
1574   --  GNAT
1575   --  Set to True to generate warnings for non-local exception raises and also
1576   --  handlers that can never handle a local raise. This warning is only ever
1577   --  generated if pragma Restrictions (No_Exception_Propagation) is set. The
1578   --  default is not to generate the warnings except that if the source has
1579   --  at least one exception handler, and this restriction is set, and the
1580   --  warning was not explicitly turned off, then it is turned on by default.
1581   --  Modified by use of -gnatw.x/.X.
1582
1583   No_Warn_On_Non_Local_Exception : Boolean := False;
1584   --  GNAT
1585   --  This is set to True if the above warning is explicitly suppressed. We
1586   --  use this to avoid turning it on by default when No_Exception_Propagation
1587   --  restriction is set and an exception handler is present.
1588
1589   Warn_On_Object_Renames_Function : Boolean := False;
1590   --  GNAT
1591   --  Set to True to generate warnings when a function result is renamed as
1592   --  an object. The default is that this warning is disabled. Modified by
1593   --  use of -gnatw.r/.R.
1594
1595   Warn_On_Obsolescent_Feature : Boolean := False;
1596   --  GNAT
1597   --  Set to True to generate warnings on use of any feature in Annex or if a
1598   --  subprogram is called for which a pragma Obsolescent applies. Modified
1599   --  by use of -gnatwj/J.
1600
1601   Warn_On_Overlap : Boolean := False;
1602   --  GNAT
1603   --  Set to True to generate warnings when a writable actual overlaps with
1604   --  another actual in a subprogram call. This applies only in modes before
1605   --  Ada 2012. Starting with Ada 2012, such overlaps are illegal.
1606   --  Modified by use of -gnatw.i/.I.
1607
1608   Warn_On_Questionable_Missing_Parens : Boolean := True;
1609   --  GNAT
1610   --  Set to True to generate warnings for cases where parentheses are missing
1611   --  and the usage is questionable, because the intent is unclear. On by
1612   --  default, modified by use of -gnatwq/Q.
1613
1614   Warn_On_Parameter_Order : Boolean := False;
1615   --  GNAT
1616   --  Set to True to generate warnings for cases where the argument list for
1617   --  a call is a sequence of identifiers that match the formal identifiers,
1618   --  but are in the wrong order.
1619
1620   Warn_On_Redundant_Constructs : Boolean := False;
1621   --  GNAT
1622   --  Set to True to generate warnings for redundant constructs (e.g. useless
1623   --  assignments/conversions). The default is that this warning is disabled.
1624   --  Modified by use of -gnatwr/R.
1625
1626   Warn_On_Reverse_Bit_Order : Boolean := True;
1627   --  GNAT
1628   --  Set to True to generate warning (informational) messages for component
1629   --  clauses that are affected by non-standard bit-order. The default is
1630   --  that this warning is enabled. Modified by -gnatw.v/.V.
1631
1632   Warn_On_Suspicious_Contract : Boolean := True;
1633   --  GNAT
1634   --  Set to True to generate warnings for suspicious contracts expressed as
1635   --  pragmas or aspects precondition and postcondition. The default is that
1636   --  this warning is enabled. Modified by use of -gnatw.t/.T.
1637
1638   Warn_On_Suspicious_Modulus_Value : Boolean := True;
1639   --  GNAT
1640   --  Set to True to generate warnings for suspicious modulus values. The
1641   --  default is that this warning is enabled. Modified by -gnatw.m/.M.
1642
1643   Warn_On_Unchecked_Conversion : Boolean := True;
1644   --  GNAT
1645   --  Set to True to generate warnings for unchecked conversions that may have
1646   --  non-portable semantics (e.g. because sizes of types differ). Modified
1647   --  by use of -gnatwz/Z.
1648
1649   Warn_On_Unordered_Enumeration_Type : Boolean := False;
1650   --  GNAT
1651   --  Set to True to generate warnings for inappropriate uses (comparisons
1652   --  and explicit ranges) on unordered enumeration types (which includes
1653   --  all enumeration types for which pragma Ordered is not given). The
1654   --  default is that this warning is disabled. Modified by -gnat.u/.U.
1655
1656   Warn_On_Unrecognized_Pragma : Boolean := True;
1657   --  GNAT
1658   --  Set to True to generate warnings for unrecognized pragmas. The default
1659   --  is that this warning is enabled. Modified by use of -gnatwg/G.
1660
1661   Warn_On_Unrepped_Components : Boolean := False;
1662   --  GNAT
1663   --  Set to True to generate warnings for the case of components of record
1664   --  which have a record representation clause but this component does not
1665   --  have a component clause. Modified by use of -gnatw.c/.C.
1666
1667   Warn_On_Warnings_Off : Boolean := False;
1668   --  GNAT
1669   --  Set to True to generate warnings for use of Pragma Warnings (Off, ent),
1670   --  where either the pragma is never used, or it could be replaced by a
1671   --  pragma Unmodified or Unreferenced. Modified by use of -gnatw.w/.W.
1672
1673   type Warning_Mode_Type is (Suppress, Normal, Treat_As_Error);
1674   Warning_Mode : Warning_Mode_Type := Normal;
1675   --  GNAT, GNATBIND
1676   --  Controls treatment of warning messages. If set to Suppress, warning
1677   --  messages are not generated at all. In Normal mode, they are generated
1678   --  but do not count as errors. In Treat_As_Error mode, warning messages
1679   --  are generated and are treated as errors.
1680
1681   Wide_Character_Encoding_Method : WC_Encoding_Method := WCEM_Brackets;
1682   --  GNAT, GNATBIND
1683   --  Method used for encoding wide characters in the source program. See
1684   --  description of type in unit System.WCh_Con for a list of the methods
1685   --  that are currently supported. Note that brackets notation is always
1686   --  recognized in source programs regardless of the setting of this
1687   --  variable. The default setting causes only the brackets notation to be
1688   --  recognized. If this is the main unit, this setting also controls the
1689   --  output of the W=? parameter in the ALI file, which is used to provide
1690   --  the default for encoding [Wide_[Wide_]]Text_IO files. For the binder,
1691   --  the value set here overrides this main unit default.
1692
1693   Wide_Character_Encoding_Method_Specified : Boolean := False;
1694   --  GNAT, GNATBIND
1695   --  Set True if the value in Wide_Character_Encoding_Method was set as
1696   --  a result of an explicit -gnatW? or -W? switch. False otherwise.
1697
1698   Xref_Active : Boolean := True;
1699   --  GNAT
1700   --  Set if cross-referencing is enabled (i.e. xref info in ALI files)
1701
1702   Zero_Formatting : Boolean := False;
1703   --  GNATBIND
1704   --  Do no formatting (no title, no leading spaces, no empty lines) in
1705   --  auxiliary outputs (-e, -K, -l, -R).
1706
1707   ----------------------------
1708   -- Configuration Settings --
1709   ----------------------------
1710
1711   --  These are settings that are used to establish the mode at the start of
1712   --  each unit. The values defined below can be affected either by command
1713   --  line switches, or by the use of appropriate configuration pragmas in a
1714   --  configuration pragma file.
1715
1716   Ada_Version_Config : Ada_Version_Type;
1717   --  GNAT
1718   --  This is the value of the configuration switch for the Ada 83 mode, as
1719   --  set by the command line switches -gnat83/95/05, and possibly modified by
1720   --  the use of configuration pragmas Ada_*. This switch is used to set the
1721   --  initial value for Ada_Version mode at the start of analysis of a unit.
1722   --  Note however that the setting of this flag is ignored for internal and
1723   --  predefined units (which are always compiled in the most up to date
1724   --  version of Ada).
1725
1726   Ada_Version_Explicit_Config : Ada_Version_Type;
1727   --  GNAT
1728   --  This is set in the same manner as Ada_Version_Config. The difference is
1729   --  that the setting of this flag is not ignored for internal and predefined
1730   --  units, which for some purposes do indeed access this value, regardless
1731   --  of the fact that they are compiled the most up to date ada version).
1732
1733   Assertions_Enabled_Config : Boolean;
1734   --  GNAT
1735   --  This is the value of the configuration switch for assertions enabled
1736   --  mode, as possibly set by the command line switch -gnata, and possibly
1737   --  modified by the use of the configuration pragma Assertion_Policy.
1738
1739   Assume_No_Invalid_Values_Config : Boolean;
1740   --  GNAT
1741   --  This is the value of the configuration switch for assuming "no invalid
1742   --  values enabled" mode, as possibly set by the command line switch
1743   --  -gnatB, and possibly modified by the use of the configuration pragma
1744   --  Assume_No_Invalid_Values.
1745
1746   Check_Float_Overflow_Config : Boolean;
1747   --  GNAT
1748   --  Set to True to check that operations on predefined unconstrained float
1749   --  types (e.g. Float, Long_Float) do not overflow and generate infinities
1750   --  or invalid values. Set by the Check_Float_Overflow pragma, or by use
1751   --  of the -gnateF switch.
1752
1753   Check_Policy_List_Config : Node_Id;
1754   --  GNAT
1755   --  This points to the list of N_Pragma nodes for Check_Policy pragmas
1756   --  that are linked through the Next_Pragma fields, with the list being
1757   --  terminated by Empty. The order is most recently processed first. This
1758   --  list includes only those pragmas in configuration pragma files.
1759
1760   Debug_Pragmas_Disabled_Config : Boolean;
1761   --  GNAT
1762   --  This is the value of the configuration switch for debug pragmas disabled
1763   --  mode, as possibly set by use of the configuration pragma Debug_Policy.
1764
1765   Debug_Pragmas_Enabled_Config : Boolean;
1766   --  GNAT
1767   --  This is the value of the configuration switch for debug pragmas enabled
1768   --  mode, as possibly set by the command line switch -gnata and possibly
1769   --  modified by the use of the configuration pragma Debug_Policy.
1770
1771   Default_Pool_Config : Node_Id := Empty;
1772   --  GNAT
1773   --  Same as Default_Pool above, except this is only for Default_Storage_Pool
1774   --  pragmas that are configuration pragmas.
1775
1776   Dynamic_Elaboration_Checks_Config : Boolean := False;
1777   --  GNAT
1778   --  Set True for dynamic elaboration checking mode, as set by the -gnatE
1779   --  switch or by the use of pragma Elaboration_Checking (Dynamic).
1780
1781   Exception_Locations_Suppressed_Config : Boolean := False;
1782   --  GNAT
1783   --  Set True by use of the configuration pragma Suppress_Exception_Messages
1784
1785   Extensions_Allowed_Config : Boolean;
1786   --  GNAT
1787   --  This is the flag that indicates whether extensions are allowed. It can
1788   --  be set True either by use of the -gnatX switch, or by use of the
1789   --  configuration pragma Extensions_Allowed (On). It is always set to True
1790   --  for internal GNAT units, since extensions are always permitted in such
1791   --  units.
1792
1793   External_Name_Exp_Casing_Config : External_Casing_Type;
1794   --  GNAT
1795   --  This is the value of the configuration switch that controls casing of
1796   --  external symbols for which an explicit external name is given. It can be
1797   --  set to Uppercase by the command line switch -gnatF, and further modified
1798   --  by the use of the configuration pragma External_Name_Casing in the
1799   --  gnat.adc file. This flag is used to set the initial value for
1800   --  External_Name_Exp_Casing at the start of analyzing each unit. Note
1801   --  however that the setting of this flag is ignored for internal and
1802   --  predefined units (which are always compiled with As_Is mode).
1803
1804   External_Name_Imp_Casing_Config : External_Casing_Type;
1805   --  GNAT
1806   --  This is the value of the configuration switch that controls casing of
1807   --  external symbols where the external name is implicitly given. It can be
1808   --  set to Uppercase by the command line switch -gnatF, and further modified
1809   --  by the use of the configuration pragma External_Name_Casing in the
1810   --  gnat.adc file. This flag is used to set the initial value for
1811   --  External_Name_Imp_Casing at the start of analyzing each unit. Note
1812   --  however that the setting of this flag is ignored for internal and
1813   --  predefined units (which are always compiled with Lowercase mode).
1814
1815   Fast_Math_Config : Boolean;
1816   --  GNAT
1817   --  This is the value of the configuration switch that controls Fast_Math
1818   --  mode, as set by a Fast_Math pragma in configuration pragmas. It is
1819   --  used to set the initial value of Fast_Math at the start of each new
1820   --  compilation unit.
1821
1822   Initialize_Scalars_Config : Boolean;
1823   --  GNAT
1824   --  This is the value of the configuration switch that is set by the
1825   --  pragma Initialize_Scalars when it appears in the gnat.adc file.
1826   --  This switch is not set when the pragma appears ahead of a given
1827   --  unit, so it does not affect the compilation of other units.
1828
1829   Optimize_Alignment_Config : Character;
1830   --  GNAT
1831   --  This is the value of the configuration switch that controls the
1832   --  alignment optimization mode, as set by an Optimize_Alignment pragma.
1833   --  It is used to set the initial value of Optimize_Alignment at the start
1834   --  of each new compilation unit, except that it is always set to 'O' (off)
1835   --  for internal units.
1836
1837   Persistent_BSS_Mode_Config : Boolean;
1838   --  GNAT
1839   --  This is the value of the configuration switch that controls whether
1840   --  potentially persistent data is to be placed in the persistent_bss
1841   --  section. It can be set True by use of the pragma Persistent_BSS.
1842   --  This flag is used to set the initial value of Persistent_BSS_Mode
1843   --  at the start of each compilation unit, except that it is always
1844   --  set False for predefined units.
1845
1846   Polling_Required_Config : Boolean;
1847   --  GNAT
1848   --  This is the value of the configuration switch that controls polling
1849   --  mode. It can be set True by the command line switch -gnatP, and then
1850   --  further modified by the use of pragma Polling in the gnat.adc file. This
1851   --  flag is used to set the initial value for Polling_Required at the start
1852   --  of analyzing each unit.
1853
1854   Short_Descriptors_Config : Boolean;
1855   --  GNAT
1856   --  This is the value of the configuration switch that controls the use of
1857   --  Short_Descriptors for setting descriptor default sizes. It can be set
1858   --  True by the use of the pragma Short_Descriptors in the gnat.adc file.
1859   --  This flag is used to set the initial value for Short_Descriptors at the
1860   --  start of analyzing each unit.
1861
1862   Use_VADS_Size_Config : Boolean;
1863   --  GNAT
1864   --  This is the value of the configuration switch that controls the use of
1865   --  VADS_Size instead of Size wherever the attribute Size is used. It can
1866   --  be set True by the use of the pragma Use_VADS_Size in the gnat.adc file.
1867   --  This flag is used to set the initial value for Use_VADS_Size at the
1868   --  start of analyzing each unit. Note however that the setting of this flag
1869   --  is ignored for internal and predefined units (which are always compiled
1870   --  with the standard Size semantics).
1871
1872   type Config_Switches_Type is private;
1873   --  Type used to save values of the switches set from Config values
1874
1875   procedure Save_Opt_Config_Switches (Save : out Config_Switches_Type);
1876   --  This procedure saves the current values of the switches which are
1877   --  initialized from the above Config values, and then resets these switches
1878   --  according to the Config value settings.
1879
1880   procedure Set_Opt_Config_Switches
1881     (Internal_Unit : Boolean;
1882      Main_Unit     : Boolean);
1883   --  This procedure sets the switches to the appropriate initial values. The
1884   --  parameter Internal_Unit is True for an internal or predefined unit, and
1885   --  affects the way the switches are set (see above). Main_Unit is true if
1886   --  switches are being set for the main unit (this affects setting of the
1887   --  assert/debug pragma switches, which are normally set false by default
1888   --  for an internal unit, except when the internal unit is the main unit,
1889   --  in which case we use the command line settings).
1890
1891   procedure Restore_Opt_Config_Switches (Save : Config_Switches_Type);
1892   --  This procedure restores a set of switch values previously saved by a
1893   --  call to Save_Opt_Switches.
1894
1895   procedure Register_Opt_Config_Switches;
1896   --  This procedure is called after processing the gnat.adc file and other
1897   --  configuration pragma files to record the values of the Config switches,
1898   --  as possibly modified by the use of command line switches and pragmas
1899   --  appearing in these files.
1900
1901   ------------------------
1902   -- Other Global Flags --
1903   ------------------------
1904
1905   Expander_Active : Boolean := False;
1906   --  A flag that indicates if expansion is active (True) or deactivated
1907   --  (False). When expansion is deactivated all calls to expander routines
1908   --  have no effect. Note that the initial setting of False is merely to
1909   --  prevent saving of an undefined value for an initial call to the
1910   --  Expander_Mode_Save_And_Set procedure. For more information on the use of
1911   --  this flag, see package Expander. Indeed this flag might more logically
1912   --  be in the spec of Expander, but it is referenced by Errout, and it
1913   --  really seems wrong for Errout to depend on Expander.
1914   --
1915   --  Note: for many purposes, it is more appropriate to test the flag
1916   --  Full_Expander_Active, which also checks that Alfa mode is not active.
1917
1918   Static_Dispatch_Tables : Boolean := True;
1919   --  This flag indicates if the backend supports generation of statically
1920   --  allocated dispatch tables. If it is True, then the front end will
1921   --  generate static aggregates for dispatch tables that contain forward
1922   --  references to addresses of subprograms not seen yet, and the back end
1923   --  must be prepared to handle this case. If it is False, then the front
1924   --  end generates assignments to initialize the dispatch table, and there
1925   --  are no such forward references. By default we build statically allocated
1926   --  dispatch tables for all library level tagged types in all platforms.This
1927   --  behavior can be disabled using switch -gnatd.t which will set this flag
1928   --  to False and revert to the previous dynamic behavior.
1929
1930   -----------------------
1931   -- Tree I/O Routines --
1932   -----------------------
1933
1934   procedure Tree_Read;
1935   --  Reads switch settings from current tree file using Tree_Read
1936
1937   procedure Tree_Write;
1938   --  Writes out switch settings to current tree file using Tree_Write
1939
1940   --------------------------
1941   -- ASIS Version Control --
1942   --------------------------
1943
1944   --  These two variables (Tree_Version_String and Tree_ASIS_Version_Number)
1945   --  are supposed to be used in the GNAT/ASIS version check performed in
1946   --  the ASIS code (this package is also a part of the ASIS implementation).
1947   --  They are set by Tree_Read procedure, so they represent the version
1948   --  number (and the version string) of the compiler which has created the
1949   --  tree, and they are supposed to be compared with the corresponding values
1950   --  from the Tree_IO and Gnatvsn packages which also are a part of ASIS
1951   --  implementation.
1952
1953   Tree_Version_String : String_Access;
1954   --  Used to store the compiler version string read from a tree file to check
1955   --  if it is from the same date as stored in the version string in Gnatvsn.
1956   --  We require that ASIS Pro can be used only with GNAT Pro, but we allow
1957   --  non-Pro ASIS and ASIS-based tools to be used with any version of the
1958   --  GNAT compiler. Therefore, we need the possibility to compare the dates
1959   --  of the corresponding source sets, using version strings that may be
1960   --  of different lengths.
1961
1962   Tree_ASIS_Version_Number : Int;
1963   --  Used to store the ASIS version number read from a tree file to check if
1964   --  it is the same as stored in the ASIS version number in Tree_IO.
1965
1966   -----------------------------------
1967   -- Modes for Formal Verification --
1968   -----------------------------------
1969
1970   Alfa_Mode : Boolean := False;
1971   --  Specific compiling mode targeting formal verification through the
1972   --  generation of Why code for those parts of the input code that belong to
1973   --  the Alfa subset of Ada. Set by debug flag -gnatd.F.
1974
1975   Strict_Alfa_Mode : Boolean := False;
1976   --  Interpret compiler permissions as strictly as possible. E.g. base ranges
1977   --  for integers are limited to the strict minimum with this option. Set by
1978   --  debug flag -gnatd.D.
1979
1980   Formal_Extensions : Boolean := False;
1981   --  When this flag is set, new aspects/pragmas/attributes are accepted,
1982   --  whose main purpose is to facilitate formal verification. Set by debug
1983   --  flag -gnatd.V.
1984
1985   function Full_Expander_Active return Boolean;
1986   pragma Inline (Full_Expander_Active);
1987   --  Returns the value of (Expander_Active and not Alfa_Mode). This "flag"
1988   --  indicates that expansion is fully active, that is, not in the reduced
1989   --  mode for Alfa (True) or that expansion is either deactivated, or active
1990   --  in the reduced mode for Alfa (False). For more information on full
1991   --  expansion, see package Expander. For more information on reduced
1992   --  Alfa expansion, see package Exp_Alfa.
1993
1994private
1995
1996   --  The following type is used to save and restore settings of switches in
1997   --  Opt that represent the configuration (i.e. result of config pragmas).
1998
1999   --  Note that Ada_Version_Explicit is not included, since this is a sticky
2000   --  flag that once set does not get reset, since the whole idea of this flag
2001   --  is to record the setting for the main unit.
2002
2003   type Config_Switches_Type is record
2004      Ada_Version                    : Ada_Version_Type;
2005      Ada_Version_Explicit           : Ada_Version_Type;
2006      Assertions_Enabled             : Boolean;
2007      Assume_No_Invalid_Values       : Boolean;
2008      Check_Float_Overflow           : Boolean;
2009      Check_Policy_List              : Node_Id;
2010      Debug_Pragmas_Disabled         : Boolean;
2011      Debug_Pragmas_Enabled          : Boolean;
2012      Default_Pool                   : Node_Id;
2013      Dynamic_Elaboration_Checks     : Boolean;
2014      Exception_Locations_Suppressed : Boolean;
2015      Extensions_Allowed             : Boolean;
2016      External_Name_Exp_Casing       : External_Casing_Type;
2017      External_Name_Imp_Casing       : External_Casing_Type;
2018      Fast_Math                      : Boolean;
2019      Initialize_Scalars             : Boolean;
2020      Normalize_Scalars              : Boolean;
2021      Optimize_Alignment             : Character;
2022      Optimize_Alignment_Local       : Boolean;
2023      Persistent_BSS_Mode            : Boolean;
2024      Polling_Required               : Boolean;
2025      Short_Descriptors              : Boolean;
2026      Use_VADS_Size                  : Boolean;
2027   end record;
2028
2029   --  The following declarations are for GCC version dependent flags. We do
2030   --  not let client code in the compiler test GCC_Version directly, but
2031   --  instead use deferred constants for relevant feature tags.
2032
2033   --  Note: there currently are no such constants defined in this section,
2034   --  since the compiler front end is currently entirely independent of the
2035   --  GCC version, which is a desirable state of affairs.
2036
2037   function get_gcc_version return Int;
2038   pragma Import (C, get_gcc_version, "get_gcc_version");
2039
2040   GCC_Version : constant Nat := get_gcc_version;
2041   --  GNATMAKE
2042   --  Indicates which version of gcc is in use (3 = 3.x, 4 = 4.x). Note that
2043   --  gcc 2.8.1 (which used to be a value of 2) is no longer supported.
2044
2045end Opt;
2046