1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2022, Free Software Foundation, Inc. --
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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with System
.Strings
; use System
.Strings
;
28 with Atree
; use Atree
;
31 with Debug
; use Debug
;
37 with Ghost
; use Ghost
;
38 with Inline
; use Inline
;
40 with Lib
.Load
; use Lib
.Load
;
42 with Namet
; use Namet
;
43 with Nlists
; use Nlists
;
49 with Restrict
; use Restrict
;
50 with Rident
; use Rident
;
52 with Snames
; use Snames
;
59 with Sem_Elab
; use Sem_Elab
;
60 with Sem_Prag
; use Sem_Prag
;
62 with Sinfo
; use Sinfo
;
63 with Sinfo
.Nodes
; use Sinfo
.Nodes
;
64 with Sinfo
.Utils
; use Sinfo
.Utils
;
65 with Sinput
; use Sinput
;
66 with Sinput
.L
; use Sinput
.L
;
68 with Tbuild
; use Tbuild
;
69 with Types
; use Types
;
74 -- Carry out package initializations. These are initializations which might
75 -- logically be performed at elaboration time, were it not for the fact
76 -- that we may be doing things more than once in the big loop over files.
77 -- Like elaboration, the order in which these calls are made is in some
78 -- cases important. For example, Lib cannot be initialized before Namet,
79 -- since it uses names table entries.
98 -- Create package Standard
100 CStand
.Create_Standard
;
102 -- Check possible symbol definitions specified by -gnateD switches
104 Prepcomp
.Process_Command_Line_Symbol_Definitions
;
106 -- If -gnatep= was specified, parse the preprocessing data file
108 if Preprocessing_Data_File
/= null then
109 Name_Len
:= Preprocessing_Data_File
'Length;
110 Name_Buffer
(1 .. Name_Len
) := Preprocessing_Data_File
.all;
111 Prepcomp
.Parse_Preprocessing_Data_File
(Name_Find
);
113 -- Otherwise, check if there were preprocessing symbols on the command
114 -- line and set preprocessing if there are.
117 Prepcomp
.Check_Symbols
;
120 -- We set Parsing_Main_Extended_Source true here to cover processing of all
121 -- the configuration pragma files, as well as the main source unit itself.
123 Parsing_Main_Extended_Source
:= True;
125 -- Now that the preprocessing situation is established, we are able to
126 -- load the main source (this is no longer done by Lib.Load.Initialize).
128 Lib
.Load
.Load_Main_Source
;
130 -- Return immediately if the main source could not be found
132 if Sinput
.Main_Source_File
<= No_Source_File
then
136 -- Read and process configuration pragma files if present
139 Dot_Gnat_Adc
: constant File_Name_Type
:= Name_Find
("./gnat.adc");
140 Gnat_Adc
: constant File_Name_Type
:= Name_Find
("gnat.adc");
142 Save_Style_Check
: constant Boolean := Opt
.Style_Check
;
143 -- Save style check mode so it can be restored later
145 Config_Pragmas
: List_Id
:= Empty_List
;
146 -- Gather configuration pragmas
148 Source_Config_File
: Source_File_Index
;
149 -- Source reference for -gnatec configuration file
154 -- We always analyze config files with style checks off, since we
155 -- don't want a miscellaneous gnat.adc that is around to discombobulate
156 -- intended -gnatg or -gnaty compilations. We also disconnect checking
157 -- for maximum line length.
159 Opt
.Style_Check
:= False;
160 Style_Check
:= False;
162 -- Capture current suppress options, which may get modified
164 Scope_Suppress
:= Opt
.Suppress_Options
;
166 -- First deal with gnat.adc file
168 if Opt
.Config_File
then
169 Source_gnat_adc
:= Load_Config_File
(Gnat_Adc
);
171 -- Case of gnat.adc file present
173 if Source_gnat_adc
> No_Source_File
then
175 -- Parse the gnat.adc file for configuration pragmas
177 Initialize_Scanner
(No_Unit
, Source_gnat_adc
);
178 Config_Pragmas
:= Par
(Configuration_Pragmas
=> True);
180 -- We add a compilation dependency for gnat.adc so that if it
181 -- changes, we force a recompilation.
183 Prepcomp
.Add_Dependency
(Source_gnat_adc
);
187 -- Now deal with specified config pragmas files if there are any
189 if Opt
.Config_File_Names
/= null then
191 -- Loop through config pragmas files
193 for Index
in Opt
.Config_File_Names
'Range loop
195 Len
: constant Natural := Config_File_Names
(Index
)'Length;
196 Str
: constant String (1 .. Len
) :=
197 Config_File_Names
(Index
).all;
199 Config_Name
: constant File_Name_Type
:= Name_Find
(Str
);
200 Temp_File
: constant Boolean :=
203 (Str
(Len
- 3 .. Len
) = ".TMP"
205 Str
(Len
- 3 .. Len
) = ".tmp");
206 -- Extension indicating a temporary config file?
209 -- Skip it if it's the default name, already loaded above.
210 -- Otherwise, we get confusing warning messages about seeing
211 -- the same thing twice.
213 if Config_Name
/= Gnat_Adc
214 and then Config_Name
/= Dot_Gnat_Adc
216 -- Load the file, error if we did not find it
218 Source_Config_File
:= Load_Config_File
(Config_Name
);
220 if Source_Config_File
<= No_Source_File
then
222 ("cannot find configuration pragmas file "
223 & Config_File_Names
(Index
).all);
225 -- If we did find the file, and it is not a temporary file,
226 -- then we add a compilation dependency for it so that if it
227 -- changes, we force a recompilation.
229 elsif not Temp_File
then
230 Prepcomp
.Add_Dependency
(Source_Config_File
);
233 -- Parse the config pragmas file, and accumulate results
235 Initialize_Scanner
(No_Unit
, Source_Config_File
);
237 (Config_Pragmas
, Par
(Configuration_Pragmas
=> True));
243 -- Now analyze all pragmas except those whose analysis must be
244 -- deferred till after the main unit is analyzed.
246 if Config_Pragmas
/= Error_List
247 and then Operating_Mode
/= Check_Syntax
249 Prag
:= First
(Config_Pragmas
);
250 while Present
(Prag
) loop
251 if not Delay_Config_Pragma_Analyze
(Prag
) then
252 Analyze_Pragma
(Prag
);
259 -- Restore style check, but if config file turned on checks, leave on
261 Opt
.Style_Check
:= Save_Style_Check
or Style_Check
;
263 -- Capture any modifications to suppress options from config pragmas
265 Opt
.Suppress_Options
:= Scope_Suppress
;
267 -- If a target dependency info file has been read through switch
268 -- -gnateT=, add it to the dependencies.
270 if Target_Dependent_Info_Read_Name
/= null then
272 Index
: Source_File_Index
;
275 Add_Str_To_Name_Buffer
(Target_Dependent_Info_Read_Name
.all);
276 Index
:= Load_Config_File
(Name_Enter
);
277 Prepcomp
.Add_Dependency
(Index
);
281 -- This is where we can capture the value of the compilation unit
282 -- specific restrictions that have been set by the config pragma
283 -- files (or from Targparm), for later restoration when processing
286 Save_Config_Cunit_Boolean_Restrictions
;
288 -- If there was a -gnatem switch, initialize the mappings of unit names
289 -- to file names and of file names to path names from the mapping file.
291 if Mapping_File_Name
/= null then
292 Fmap
.Initialize
(Mapping_File_Name
.all);
295 -- Adjust Optimize_Alignment mode from debug switches if necessary
297 if Debug_Flag_Dot_SS
then
298 Optimize_Alignment
:= 'S';
299 elsif Debug_Flag_Dot_TT
then
300 Optimize_Alignment
:= 'T';
303 -- We have now processed the command line switches, and the
304 -- configuration pragma files, so this is the point at which we want to
305 -- capture the values of the configuration switches (see Opt for further
308 Register_Config_Switches
;
310 -- Check for file which contains No_Body pragma
312 if Source_File_Is_No_Body
(Source_Index
(Main_Unit
)) then
313 Change_Main_Unit_To_Spec
;
316 -- Initialize the scanner. Note that we do this after the call to
317 -- Create_Standard, which uses the scanner in its processing of
318 -- floating-point bounds.
320 Initialize_Scanner
(Main_Unit
, Source_Index
(Main_Unit
));
322 -- Here we call the parser to parse the compilation unit (or units in
323 -- the check syntax mode, but in that case we won't go on to the
324 -- semantics in any case).
326 Discard_List
(Par
(Configuration_Pragmas
=> False));
327 Parsing_Main_Extended_Source
:= False;
329 -- The main unit is now loaded, and subunits of it can be loaded,
330 -- without reporting spurious loading circularities.
332 Set_Loading
(Main_Unit
, False);
334 -- Now that the main unit is installed, we can complete the analysis
335 -- of the pragmas in gnat.adc and the configuration file, that require
336 -- a context for their semantic processing.
338 if Config_Pragmas
/= Error_List
339 and then Operating_Mode
/= Check_Syntax
341 -- Do not attempt to process deferred configuration pragmas if the
342 -- main unit failed to load, to avoid cascaded inconsistencies that
343 -- can lead to a compiler crash.
345 and then Fatal_Error
(Main_Unit
) /= Error_Detected
347 -- Pragmas that require some semantic activity, such as
348 -- Interrupt_State, cannot be processed until the main unit is
349 -- installed, because they require a compilation unit on which to
350 -- attach with_clauses, etc. So analyze them now.
356 Prag
:= First
(Config_Pragmas
);
357 while Present
(Prag
) loop
359 -- Guard against the case where a configuration pragma may be
360 -- split into multiple pragmas and the original rewritten as a
363 if Nkind
(Prag
) = N_Pragma
364 and then Delay_Config_Pragma_Analyze
(Prag
)
366 Analyze_Pragma
(Prag
);
374 -- If we have restriction No_Exception_Propagation, and we did not have
375 -- an explicit switch turning off Warn_On_Non_Local_Exception, then turn
376 -- on this warning by default if we have encountered an exception
379 if Restriction_Check_Required
(No_Exception_Propagation
)
380 and then not No_Warn_On_Non_Local_Exception
381 and then Exception_Handler_Encountered
383 Warn_On_Non_Local_Exception
:= True;
386 -- Disable Initialize_Scalars for runtime files to avoid circular
389 if Initialize_Scalars
390 and then Fname
.Is_Predefined_File_Name
(File_Name
(Main_Source_File
))
392 Initialize_Scalars
:= False;
393 Init_Or_Norm_Scalars
:= Normalize_Scalars
;
396 -- Now on to the semantics. Skip if in syntax only mode
398 if Operating_Mode
/= Check_Syntax
then
400 -- Install the configuration pragmas in the tree
403 (Aux_Decls_Node
(Cunit
(Main_Unit
)), Config_Pragmas
);
405 -- Following steps are skipped if we had a fatal error during parsing
407 if Fatal_Error
(Main_Unit
) /= Error_Detected
then
409 -- Reset Operating_Mode to Check_Semantics for subunits. We cannot
410 -- actually generate code for subunits, so we suppress expansion.
411 -- This also corrects certain problems that occur if we try to
412 -- incorporate subunits at a lower level.
414 if Operating_Mode
= Generate_Code
415 and then Nkind
(Unit
(Cunit
(Main_Unit
))) = N_Subunit
417 Operating_Mode
:= Check_Semantics
;
420 -- Analyze (and possibly expand) main unit
422 Scope_Suppress
:= Suppress_Options
;
423 Semantics
(Cunit
(Main_Unit
));
425 -- Cleanup processing after completing main analysis
427 -- In GNATprove_Mode we do not perform most expansions but body
428 -- instantiation is needed.
431 (Operating_Mode
= Generate_Code
432 or else Operating_Mode
= Check_Semantics
);
434 if Operating_Mode
= Generate_Code
435 or else GNATprove_Mode
440 -- Analyze all inlined bodies, check access-before-elaboration
441 -- rules, and remove ignored Ghost code when generating code or
442 -- compiling for GNATprove.
444 if Operating_Mode
= Generate_Code
or else GNATprove_Mode
then
445 if Inline_Processing_Required
then
446 Analyze_Inlined_Bodies
;
449 -- Remove entities from program that do not have any execution
452 if Debug_Flag_UU
then
453 Collect_Garbage_Entities
;
456 if Legacy_Elaboration_Checks
then
460 -- Examine all top level scenarios collected during analysis
461 -- and resolution. Diagnose conditional ABEs, install run-time
462 -- checks to catch conditional ABEs, and guarantee the prior
463 -- elaboration of external units.
465 Check_Elaboration_Scenarios
;
467 -- Examine all top level scenarios collected during analysis and
468 -- resolution in order to diagnose conditional ABEs, even in the
469 -- presence of serious errors.
472 Check_Elaboration_Scenarios
;
475 -- List library units if requested
481 -- Output waiting warning messages
483 Sem_Warn
.Output_Non_Modified_In_Out_Warnings
;
484 Sem_Warn
.Output_Unreferenced_Messages
;
485 Sem_Warn
.Check_Unused_Withs
;
486 Sem_Warn
.Output_Unused_Warnings_Off_Warnings
;
488 -- Remove any ignored Ghost code as it must not appear in the
489 -- executable. This action must be performed very late because it
490 -- heavily alters the tree.
492 if Operating_Mode
= Generate_Code
or else GNATprove_Mode
then
493 Remove_Ignored_Ghost_Code
;
496 -- At this stage we can unnest subprogram bodies if required
498 if Total_Errors_Detected
= 0 then
499 Exp_Unst
.Unnest_Subprograms
(Cunit
(Main_Unit
));
506 -- Qualify all entity names in inner packages, package bodies, etc
508 if not GNATprove_Mode
then
509 Exp_Dbug
.Qualify_All_Entity_Names
;
512 -- SCIL backend requirement. Check that SCIL nodes associated with
513 -- dispatching calls reference subprogram calls.
515 if Generate_SCIL
then
516 pragma Debug
(Sem_SCIL
.Check_SCIL_Nodes
(Cunit
(Main_Unit
)));
520 -- Verify the validity of the tree
522 if Debug_Flag_Underscore_VV
then
523 VAST
.Check_Tree
(Cunit
(Main_Unit
));
526 -- Dump the source now. Note that we do this as soon as the analysis
527 -- of the tree is complete, because it is not just a dump in the case
528 -- of -gnatD, where it rewrites all source locations in the tree.
532 -- Check again for configuration pragmas that appear in the context
533 -- of the main unit. These pragmas only affect the main unit, and the
534 -- corresponding flag is reset after each call to Semantics, but they
535 -- may affect the generated ali for the unit, and therefore the flag
536 -- must be set properly after compilation. Currently we only check for
537 -- Initialize_Scalars, but others should be checked: as well???
543 Item
:= First
(Context_Items
(Cunit
(Main_Unit
)));
544 while Present
(Item
) loop
545 if Nkind
(Item
) = N_Pragma
546 and then Pragma_Name
(Item
) = Name_Initialize_Scalars
548 Initialize_Scalars
:= True;
555 -- If a mapping file has been specified by a -gnatem switch, update
556 -- it if there has been some sources that were not in the mappings.
558 if Mapping_File_Name
/= null then
559 Fmap
.Update_Mapping_File
(Mapping_File_Name
.all);