1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004 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 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree
; use Atree
;
28 with Back_End
; use Back_End
;
30 with Csets
; use Csets
;
31 with Debug
; use Debug
;
33 with Errout
; use Errout
;
35 with Fname
; use Fname
;
36 with Fname
.UF
; use Fname
.UF
;
38 with Gnatvsn
; use Gnatvsn
;
42 with Lib
.Writ
; use Lib
.Writ
;
44 with Namet
; use Namet
;
47 with Osint
; use Osint
;
48 with Output
; use Output
;
50 with Repinfo
; use Repinfo
;
59 with Sinfo
; use Sinfo
;
60 with Sinput
.L
; use Sinput
.L
;
62 with Sprint
; use Sprint
;
66 with Treepr
; use Treepr
;
68 with Types
; use Types
;
69 with Uintp
; use Uintp
;
70 with Uname
; use Uname
;
74 with System
.Assertions
;
77 Main_Unit_Node
: Node_Id
;
78 -- Compilation unit node for main unit
80 Main_Kind
: Node_Kind
;
81 -- Kind of main compilation unit node
83 Back_End_Mode
: Back_End
.Back_End_Mode_Type
;
84 -- Record back end mode
87 -- This inner block is set up to catch assertion errors and constraint
88 -- errors. Since the code for handling these errors can cause another
89 -- exception to be raised (namely Unrecoverable_Error), we need two
90 -- nested blocks, so that the outer one handles unrecoverable error.
93 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
94 -- because it initialize a table that is filled by
95 -- Scan_Compiler_Arguments.
101 Scan_Compiler_Arguments
;
102 Osint
.Add_Default_Search_Dirs
;
120 Sem_Type
.Init_Interp_Tables
;
122 -- Acquire target parameters from system.ads (source of package System)
127 S
: Source_File_Index
;
131 Name_Buffer
(1 .. 10) := "system.ads";
134 S
:= Load_Source_File
(N
);
136 if S
= No_Source_File
then
138 ("fatal error, run-time library not installed correctly");
140 ("cannot locate file system.ads");
141 raise Unrecoverable_Error
;
143 -- Remember source index of system.ads (which was read successfully)
146 System_Source_File_Index
:= S
;
149 Targparm
.Get_Target_Parameters
150 (System_Text
=> Source_Text
(S
),
151 Source_First
=> Source_First
(S
),
152 Source_Last
=> Source_Last
(S
));
154 -- Acquire configuration pragma information from Targparm
156 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
159 -- Set Configurable_Run_Time mode if system.ads flag set
161 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
162 Configurable_Run_Time_Mode
:= True;
165 -- Set -gnatR3m mode if debug flag A set
167 if Debug_Flag_AA
then
168 Back_Annotate_Rep_Info
:= True;
169 List_Representation_Info
:= 1;
170 List_Representation_Info_Mechanisms
:= True;
173 -- Output copyright notice if full list mode
175 if (Verbose_Mode
or Full_List
)
176 and then (not Debug_Flag_7
)
180 Write_Str
(Gnat_Version_String
);
182 Write_Str
("Copyright 1992-2004 Free Software Foundation, Inc.");
186 -- Before we do anything else, adjust certain global values for
187 -- debug switches which modify their normal natural settings.
190 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
194 Targparm
.OpenVMS_On_Target
:= True;
195 Hostparm
.OpenVMS
:= True;
198 if Debug_Flag_FF
then
199 Targparm
.Frontend_Layout_On_Target
:= True;
202 -- We take the default exception mechanism into account
204 if Targparm
.ZCX_By_Default_On_Target
then
205 if Targparm
.GCC_ZCX_Support_On_Target
then
206 Exception_Mechanism
:= Back_End_ZCX_Exceptions
;
208 Exception_Mechanism
:= Front_End_ZCX_Exceptions
;
212 -- We take the command line exception mechanism into account
214 if Opt
.Zero_Cost_Exceptions_Set
then
215 if Opt
.Zero_Cost_Exceptions_Val
= False then
216 Exception_Mechanism
:= Front_End_Setjmp_Longjmp_Exceptions
;
218 elsif Debug_Flag_XX
then
219 Exception_Mechanism
:= Front_End_ZCX_Exceptions
;
221 elsif Targparm
.GCC_ZCX_Support_On_Target
then
222 Exception_Mechanism
:= Back_End_ZCX_Exceptions
;
224 elsif Targparm
.Front_End_ZCX_Support_On_Target
then
225 Exception_Mechanism
:= Front_End_ZCX_Exceptions
;
229 ("Zero Cost Exceptions not supported on this target");
233 -- Set proper status for overflow checks. We turn on overflow checks
234 -- if -gnatp was not specified, and either -gnato is set or the back
235 -- end takes care of overflow checks. Otherwise we suppress overflow
236 -- checks by default (since front end checks are expensive).
238 if not Opt
.Suppress_Checks
239 and then (Opt
.Enable_Overflow_Checks
241 (Targparm
.Backend_Divide_Checks_On_Target
243 Targparm
.Backend_Overflow_Checks_On_Target
))
245 Suppress_Options
(Overflow_Check
) := False;
247 Suppress_Options
(Overflow_Check
) := True;
250 -- Check we have exactly one source file, this happens only in
251 -- the case where the driver is called directly, it cannot happen
252 -- when gnat1 is invoked from gcc in the normal case.
254 if Osint
.Number_Of_Files
/= 1 then
257 Osint
.Fail
("you must provide one source file");
259 elsif Usage_Requested
then
263 Original_Operating_Mode
:= Operating_Mode
;
265 Main_Unit_Node
:= Cunit
(Main_Unit
);
266 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
268 -- Check for suspicious or incorrect body present if we are doing
269 -- semantic checking. We omit this check in syntax only mode, because
270 -- in that case we do not know if we need a body or not.
272 if Operating_Mode
/= Check_Syntax
274 ((Main_Kind
= N_Package_Declaration
275 and then not Body_Required
(Main_Unit_Node
))
276 or else (Main_Kind
= N_Generic_Package_Declaration
277 and then not Body_Required
(Main_Unit_Node
))
278 or else Main_Kind
= N_Package_Renaming_Declaration
279 or else Main_Kind
= N_Subprogram_Renaming_Declaration
280 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
281 in N_Generic_Instantiation
)
284 Sname
: Unit_Name_Type
:= Unit_Name
(Main_Unit
);
285 Src_Ind
: Source_File_Index
;
286 Fname
: File_Name_Type
;
288 procedure Bad_Body
(Msg
: String);
289 -- Issue message for bad body found
291 procedure Bad_Body
(Msg
: String) is
293 Error_Msg_N
(Msg
, Main_Unit_Node
);
294 Error_Msg_Name_1
:= Fname
;
296 ("remove incorrect body in file{!", Main_Unit_Node
);
300 Sname
:= Unit_Name
(Main_Unit
);
302 -- If we do not already have a body name, then get the body
303 -- name (but how can we have a body name here ???)
305 if not Is_Body_Name
(Sname
) then
306 Sname
:= Get_Body_Name
(Sname
);
309 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
310 Src_Ind
:= Load_Source_File
(Fname
);
312 -- Case where body is present and it is not a subunit. Exclude
313 -- the subunit case, because it has nothing to do with the
314 -- package we are compiling. It is illegal for a child unit
315 -- and a subunit with the same expanded name (RM 10.2(9)) to
316 -- appear together in a partition, but there is nothing to
317 -- stop a compilation environment from having both, and the
318 -- test here simply allows that. If there is an attempt to
319 -- include both in a partition, this is diagnosed at bind time.
320 -- In Ada 83 mode this is not a warning case.
322 -- Note: if weird file names are being used, we can have a
323 -- situation where the file name that supposedly contains a
324 -- body, in fact contains a spec, or we can't tell what it
325 -- contains. Skip the error message in these cases.
327 if Src_Ind
/= No_Source_File
328 and then Get_Expected_Unit_Type
(Fname
) = Expect_Body
329 and then not Source_File_Is_Subunit
(Src_Ind
)
331 Error_Msg_Name_1
:= Sname
;
333 -- Ada 83 case of a package body being ignored. This is not
334 -- an error as far as the Ada 83 RM is concerned, but it is
335 -- almost certainly not what is wanted so output a warning.
336 -- Give this message only if there were no errors, since
337 -- otherwise it may be incorrect (we may have misinterpreted
338 -- a junk spec as not needing a body when it really does).
340 if Main_Kind
= N_Package_Declaration
341 and then Ada_Version
= Ada_83
342 and then Operating_Mode
= Generate_Code
343 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
344 and then not Compilation_Errors
347 ("package % does not require a body?!", Main_Unit_Node
);
348 Error_Msg_Name_1
:= Fname
;
350 ("body in file{?! will be ignored", Main_Unit_Node
);
352 -- Ada 95 cases of a body file present when no body is
353 -- permitted. This we consider to be an error.
356 -- For generic instantiations, we never allow a body
358 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
359 in N_Generic_Instantiation
362 ("generic instantiation for % does not allow a body");
364 -- A library unit that is a renaming never allows a body
366 elsif Main_Kind
in N_Renaming_Declaration
then
368 ("renaming declaration for % does not allow a body!");
370 -- Remaining cases are packages and generic packages.
371 -- Here we only do the test if there are no previous
372 -- errors, because if there are errors, they may lead
373 -- us to incorrectly believe that a package does not
374 -- allow a body when in fact it does.
376 elsif not Compilation_Errors
then
377 if Main_Kind
= N_Package_Declaration
then
378 Bad_Body
("package % does not allow a body!");
380 elsif Main_Kind
= N_Generic_Package_Declaration
then
381 Bad_Body
("generic package % does not allow a body!");
390 -- Exit if compilation errors detected
392 if Compilation_Errors
then
394 Sem_Ch13
.Validate_Unchecked_Conversions
;
398 -- Generate ALI file if specially requested
400 if Opt
.Force_ALI_Tree_File
then
401 Write_ALI
(Object
=> False);
405 Exit_Program
(E_Errors
);
408 -- Set Generate_Code on main unit and its spec. We do this even if
409 -- are not generating code, since Lib-Writ uses this to determine
410 -- which units get written in the ali file.
412 Set_Generate_Code
(Main_Unit
);
414 -- If we have a corresponding spec, then we need object
415 -- code for the spec unit as well
417 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
418 and then not Acts_As_Spec
(Main_Unit_Node
)
421 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
424 -- Case of no code required to be generated, exit indicating no error
426 if Original_Operating_Mode
= Check_Syntax
then
431 Exit_Program
(E_Success
);
433 elsif Original_Operating_Mode
= Check_Semantics
then
434 Back_End_Mode
:= Declarations_Only
;
436 -- All remaining cases are cases in which the user requested that code
437 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if
438 -- we can in fact satisfy this request.
440 -- Cannot generate code if someone has turned off code generation
441 -- for any reason at all. We will try to figure out a reason below.
443 elsif Operating_Mode
/= Generate_Code
then
444 Back_End_Mode
:= Skip
;
446 -- We can generate code for a subprogram body unless there were
447 -- missing subunits. Note that we always generate code for all
448 -- generic units (a change from some previous versions of GNAT).
450 elsif Main_Kind
= N_Subprogram_Body
451 and then not Subunits_Missing
453 Back_End_Mode
:= Generate_Object
;
455 -- We can generate code for a package body unless there are subunits
456 -- missing (note that we always generate code for generic units, which
457 -- is a change from some earlier versions of GNAT).
459 elsif Main_Kind
= N_Package_Body
460 and then not Subunits_Missing
462 Back_End_Mode
:= Generate_Object
;
464 -- We can generate code for a package declaration or a subprogram
465 -- declaration only if it does not required a body.
467 elsif (Main_Kind
= N_Package_Declaration
469 Main_Kind
= N_Subprogram_Declaration
)
471 (not Body_Required
(Main_Unit_Node
)
473 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
475 Back_End_Mode
:= Generate_Object
;
477 -- We can generate code for a generic package declaration of a generic
478 -- subprogram declaration only if does not require a body.
480 elsif (Main_Kind
= N_Generic_Package_Declaration
482 Main_Kind
= N_Generic_Subprogram_Declaration
)
483 and then not Body_Required
(Main_Unit_Node
)
485 Back_End_Mode
:= Generate_Object
;
487 -- Compilation units that are renamings do not require bodies,
488 -- so we can generate code for them.
490 elsif Main_Kind
= N_Package_Renaming_Declaration
491 or else Main_Kind
= N_Subprogram_Renaming_Declaration
493 Back_End_Mode
:= Generate_Object
;
495 -- Compilation units that are generic renamings do not require bodies
496 -- so we can generate code for them.
498 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
499 Back_End_Mode
:= Generate_Object
;
501 -- In all other cases (specs which have bodies, generics, and bodies
502 -- where subunits are missing), we cannot generate code and we generate
503 -- a warning message. Note that generic instantiations are gone at this
504 -- stage since they have been replaced by their instances.
507 Back_End_Mode
:= Skip
;
510 -- At this stage Call_Back_End is set to indicate if the backend
511 -- should be called to generate code. If it is not set, then code
512 -- generation has been turned off, even though code was requested
513 -- by the original command. This is not an error from the user
514 -- point of view, but it is an error from the point of view of
515 -- the gcc driver, so we must exit with an error status.
517 -- We generate an informative message (from the gcc point of view,
518 -- it is an error message, but from the users point of view this
519 -- is not an error, just a consequence of compiling something that
520 -- cannot generate code).
522 if Back_End_Mode
= Skip
then
523 Write_Str
("cannot generate code for ");
525 Write_Name
(Unit_File_Name
(Main_Unit
));
527 if Subunits_Missing
then
528 Write_Str
(" (missing subunits)");
530 Write_Str
("to check parent unit");
532 elsif Main_Kind
= N_Subunit
then
533 Write_Str
(" (subunit)");
535 Write_Str
("to check subunit");
537 elsif Main_Kind
= N_Subprogram_Declaration
then
538 Write_Str
(" (subprogram spec)");
540 Write_Str
("to check subprogram spec");
542 -- Generic package body in GNAT implementation mode
544 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
545 Write_Str
(" (predefined generic)");
547 Write_Str
("to check predefined generic");
549 -- Only other case is a package spec
552 Write_Str
(" (package spec)");
554 Write_Str
("to check package spec");
557 Write_Str
(" for errors, use ");
559 if Hostparm
.OpenVMS
then
560 Write_Str
("/NOLOAD");
562 Write_Str
("-gnatc");
567 Sem_Ch13
.Validate_Unchecked_Conversions
;
571 Write_ALI
(Object
=> False);
574 -- Exit program with error indication, to kill object file
576 Exit_Program
(E_No_Code
);
579 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also
580 -- set as indicated by Back_Annotate_Rep_Info being set to True.
582 -- We don't call for annotations on a subunit, because to process those
583 -- the back-end requires that the parent(s) be properly compiled.
585 -- Annotation is suppressed for targets where front-end layout is
586 -- enabled, because the front end determines representations.
588 -- Annotation is also suppressed in the case of compiling for
589 -- the Java VM, since representations are largely symbolic there.
591 if Back_End_Mode
= Declarations_Only
592 and then (not Back_Annotate_Rep_Info
593 or else Main_Kind
= N_Subunit
594 or else Targparm
.Frontend_Layout_On_Target
595 or else Hostparm
.Java_VM
)
597 Sem_Ch13
.Validate_Unchecked_Conversions
;
599 Write_ALI
(Object
=> False);
606 -- Ensure that we properly register a dependency on system.ads,
607 -- since even if we do not semantically depend on this, Targparm
608 -- has read system parameters from the system.ads file.
610 Lib
.Writ
.Ensure_System_Dependency
;
612 -- Add dependencies, if any, on preprocessing data file and on
613 -- preprocessing definition file(s).
615 Prepcomp
.Add_Dependencies
;
617 -- Back end needs to explicitly unlock tables it needs to touch
630 -- Here we call the back end to generate the output code
632 Back_End
.Call_Back_End
(Back_End_Mode
);
634 -- Once the backend is complete, we unlock the names table. This
635 -- call allows a few extra entries, needed for example for the file
636 -- name for the library file output.
640 -- Validate unchecked conversions (using the values for size
641 -- and alignment annotated by the backend where possible).
643 Sem_Ch13
.Validate_Unchecked_Conversions
;
645 -- Now we complete output of errors, rep info and the tree info.
646 -- These are delayed till now, since it is perfectly possible for
647 -- gigi to generate errors, modify the tree (in particular by setting
648 -- flags indicating that elaboration is required, and also to back
649 -- annotate representation information for List_Rep_Info.
654 -- Only write the library if the backend did not generate any error
655 -- messages. Otherwise signal errors to the driver program so that
656 -- there will be no attempt to generate an object file.
658 if Compilation_Errors
then
660 Exit_Program
(E_Errors
);
663 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
));
665 -- Generate the ASIS tree after writing the ALI file, since in
666 -- ASIS mode, Write_ALI may in fact result in further tree
667 -- decoration from the original tree file. Note that we dump
668 -- the tree just before generating it, so that the dump will
669 -- exactly reflect what is written out.
674 -- Finalize name table and we are all done
679 -- Handle fatal internal compiler errors
681 when System
.Assertions
.Assert_Failure
=>
682 Comperr
.Compiler_Abort
("Assert_Failure");
684 when Constraint_Error
=>
685 Comperr
.Compiler_Abort
("Constraint_Error");
687 when Program_Error
=>
688 Comperr
.Compiler_Abort
("Program_Error");
690 when Storage_Error
=>
692 -- Assume this is a bug. If it is real, the message will in
693 -- any case say Storage_Error, giving a strong hint!
695 Comperr
.Compiler_Abort
("Storage_Error");
698 -- The outer exception handles an unrecoverable error
701 when Unrecoverable_Error
=>
705 Write_Str
("compilation abandoned");
711 Exit_Program
(E_Errors
);