1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, 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 Atree
; use Atree
;
27 with Back_End
; use Back_End
;
29 with Csets
; use Csets
;
30 with Debug
; use Debug
;
32 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
;
51 with Repinfo
; use Repinfo
;
53 with Rident
; use Rident
;
63 with Sinfo
; use Sinfo
;
64 with Sinput
.L
; use Sinput
.L
;
66 with Sprint
; use Sprint
;
68 with Stylesw
; use Stylesw
;
69 with Targparm
; use Targparm
;
71 with Treepr
; use Treepr
;
73 with Types
; use Types
;
74 with Uintp
; use Uintp
;
75 with Uname
; use Uname
;
78 with Validsw
; use Validsw
;
80 with System
.Assertions
;
83 Main_Unit_Node
: Node_Id
;
84 -- Compilation unit node for main unit
86 Main_Kind
: Node_Kind
;
87 -- Kind of main compilation unit node
89 Back_End_Mode
: Back_End
.Back_End_Mode_Type
;
90 -- Record back end mode
92 procedure Adjust_Global_Switches
;
93 -- There are various interactions between front end switch settings,
94 -- including debug switch settings and target dependent parameters.
95 -- This procedure takes care of properly handling these interactions.
96 -- We do it after scanning out all the switches, so that we are not
97 -- depending on the order in which switches appear.
99 procedure Check_Bad_Body
;
100 -- Called to check if the unit we are compiling has a bad body
102 procedure Check_Rep_Info
;
103 -- Called when we are not generating code, to check if -gnatR was requested
104 -- and if so, explain that we will not be honoring the request.
106 procedure Check_Library_Items
;
107 -- For debugging -- checks the behavior of Walk_Library_Items
108 pragma Warnings
(Off
, Check_Library_Items
);
109 -- In case the call below is commented out
111 ----------------------------
112 -- Adjust_Global_Switches --
113 ----------------------------
115 procedure Adjust_Global_Switches
is
117 -- Debug flag -gnatd.I is a synonym for Generate_SCIL and requires code
121 and then Operating_Mode
= Generate_Code
123 Generate_SCIL
:= True;
126 -- Disable CodePeer_Mode in Check_Syntax, since we need front-end
129 if Operating_Mode
= Check_Syntax
then
130 CodePeer_Mode
:= False;
133 -- Set ASIS mode if -gnatt and -gnatc are set
135 if Operating_Mode
= Check_Semantics
and then Tree_Output
then
138 -- Turn off inlining in ASIS mode, since ASIS cannot handle the extra
139 -- information in the trees caused by inlining being active.
141 -- More specifically, the tree seems to be malformed from the ASIS
142 -- point of view if -gnatc and -gnatn appear together???
144 Inline_Active
:= False;
146 -- Turn off SCIL generation and CodePeer mode in semantics mode,
147 -- since SCIL requires front-end expansion.
149 Generate_SCIL
:= False;
150 CodePeer_Mode
:= False;
153 -- SCIL mode needs to disable front-end inlining since the generated
154 -- trees (in particular order and consistency between specs compiled
155 -- as part of a main unit or as part of a with-clause) are causing
158 if Generate_SCIL
then
159 Front_End_Inlining
:= False;
162 -- Tune settings for optimal SCIL generation in CodePeer mode
164 if CodePeer_Mode
then
166 -- Turn off inlining, confuses CodePeer output and gains nothing
168 Front_End_Inlining
:= False;
169 Inline_Active
:= False;
171 -- Disable front-end optimizations, to keep the tree as close to the
172 -- source code as possible, and also to avoid inconsistencies between
173 -- trees when using different optimization switches.
175 Optimization_Level
:= 0;
177 -- Enable some restrictions systematically to simplify the generated
178 -- code (and ease analysis). Note that restriction checks are also
179 -- disabled in CodePeer mode, see Restrict.Check_Restriction, and
180 -- user specified Restrictions pragmas are ignored, see
181 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
183 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
184 Restrict
.Restrictions
.Set
(No_Task_Hierarchy
) := True;
185 Restrict
.Restrictions
.Set
(No_Abort_Statements
) := True;
186 Restrict
.Restrictions
.Set
(Max_Asynchronous_Select_Nesting
) := True;
187 Restrict
.Restrictions
.Value
(Max_Asynchronous_Select_Nesting
) := 0;
189 -- Suppress overflow, division by zero and access checks since they
190 -- are handled implicitly by CodePeer.
192 -- Turn off dynamic elaboration checks: generates inconsistencies in
193 -- trees between specs compiled as part of a main unit or as part of
196 -- Turn off alignment checks: these cannot be proved statically by
197 -- CodePeer and generate false positives.
199 -- Enable all other language checks
202 (Access_Check
=> True,
203 Alignment_Check
=> True,
204 Division_Check
=> True,
205 Elaboration_Check
=> True,
206 Overflow_Check
=> True,
208 Enable_Overflow_Checks
:= False;
209 Dynamic_Elaboration_Checks
:= False;
211 -- Kill debug of generated code, since it messes up sloc values
213 Debug_Generated_Code
:= False;
215 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
216 -- Do we really need to spend time generating xref in CodePeer
217 -- mode??? Consider setting Xref_Active to False.
221 -- Polling mode forced off, since it generates confusing junk
223 Polling_Required
:= False;
225 -- Set operating mode to Generate_Code to benefit from full front-end
226 -- expansion (e.g. generics).
228 Operating_Mode
:= Generate_Code
;
230 -- We need SCIL generation of course
232 Generate_SCIL
:= True;
234 -- Enable assertions and debug pragmas, since they give CodePeer
235 -- valuable extra information.
237 Assertions_Enabled
:= True;
238 Debug_Pragmas_Enabled
:= True;
240 -- Disable all simple value propagation. This is an optimization
241 -- which is valuable for code optimization, and also for generation
242 -- of compiler warnings, but these are being turned off by default,
243 -- and CodePeer generates better messages (referencing original
244 -- variables) this way.
246 Debug_Flag_MM
:= True;
248 -- Set normal RM validity checking, and checking of IN OUT parameters
249 -- (this might give CodePeer more useful checks to analyze, to be
250 -- confirmed???). All other validity checking is turned off, since
251 -- this can generate very complex trees that only confuse CodePeer
252 -- and do not bring enough useful info.
254 Reset_Validity_Check_Options
;
255 Validity_Check_Default
:= True;
256 Validity_Check_In_Out_Params
:= True;
257 Validity_Check_In_Params
:= True;
259 -- Turn off style check options since we are not interested in any
260 -- front-end warnings when we are getting CodePeer output.
262 Reset_Style_Check_Options
;
264 -- Always perform semantics and generate ali files in CodePeer mode,
265 -- so that a gnatmake -c -k will proceed further when possible.
267 Force_ALI_Tree_File
:= True;
268 Try_Semantics
:= True;
271 -- Set Configurable_Run_Time mode if system.ads flag set
273 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
274 Configurable_Run_Time_Mode
:= True;
277 -- Set -gnatR3m mode if debug flag A set
279 if Debug_Flag_AA
then
280 Back_Annotate_Rep_Info
:= True;
281 List_Representation_Info
:= 1;
282 List_Representation_Info_Mechanisms
:= True;
285 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
287 if Debug_Flag_Dot_A
then
288 Ttypes
.Target_Strict_Alignment
:= True;
291 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
292 -- is enabled. The front end's layout phase currently treats types that
293 -- have discriminant-dependent arrays as not being static even when a
294 -- discriminant constraint on the type is static, and this leads to
295 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
297 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
298 Static_Dispatch_Tables
:= False;
301 -- Flip endian mode if -gnatd8 set
304 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
307 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
308 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
309 -- before doing this, so we know if we are in real OpenVMS or not!
311 Opt
.True_VMS_Target
:= Targparm
.OpenVMS_On_Target
;
314 Targparm
.OpenVMS_On_Target
:= True;
315 Hostparm
.OpenVMS
:= True;
318 -- Activate front end layout if debug flag -gnatdF is set
320 if Debug_Flag_FF
then
321 Targparm
.Frontend_Layout_On_Target
:= True;
324 -- Set and check exception mechanism
326 if Targparm
.ZCX_By_Default_On_Target
then
327 if Targparm
.GCC_ZCX_Support_On_Target
then
328 Exception_Mechanism
:= Back_End_Exceptions
;
330 Osint
.Fail
("Zero Cost Exceptions not supported on this target");
334 -- Set proper status for overflow checks. We turn on overflow checks if
335 -- -gnatp was not specified, and either -gnato is set or the back-end
336 -- takes care of overflow checks. Otherwise we suppress overflow checks
337 -- by default (since front end checks are expensive).
339 if not Opt
.Suppress_Checks
340 and then (Opt
.Enable_Overflow_Checks
342 (Targparm
.Backend_Divide_Checks_On_Target
344 Targparm
.Backend_Overflow_Checks_On_Target
))
346 Suppress_Options
(Overflow_Check
) := False;
348 Suppress_Options
(Overflow_Check
) := True;
351 -- Set switch indicating if we can use N_Expression_With_Actions
353 -- Debug flag -gnatd.X decisively sets usage on
355 if Debug_Flag_Dot_XX
then
356 Use_Expression_With_Actions
:= True;
358 -- Debug flag -gnatd.Y decisively sets usage off
360 elsif Debug_Flag_Dot_YY
then
361 Use_Expression_With_Actions
:= False;
363 -- Otherwise this feature is implemented, so we allow its use
366 Use_Expression_With_Actions
:= True;
369 -- Set switch indicating if back end can handle limited types, and
370 -- guarantee that no incorrect copies are made (e.g. in the context
371 -- of a conditional expression).
373 -- Debug flag -gnatd.L decisively sets usage on
375 if Debug_Flag_Dot_LL
then
376 Back_End_Handles_Limited_Types
:= True;
378 -- If no debug flag, usage off for AAMP, VM, SCIL cases
381 or else VM_Target
/= No_VM
382 or else Generate_SCIL
384 Back_End_Handles_Limited_Types
:= False;
386 -- Otherwise normal gcc back end, for now still turn flag off by
387 -- default, since there are unresolved problems in the front end.
390 Back_End_Handles_Limited_Types
:= False;
392 end Adjust_Global_Switches
;
398 procedure Check_Bad_Body
is
399 Sname
: Unit_Name_Type
;
400 Src_Ind
: Source_File_Index
;
401 Fname
: File_Name_Type
;
403 procedure Bad_Body_Error
(Msg
: String);
404 -- Issue message for bad body found
410 procedure Bad_Body_Error
(Msg
: String) is
412 Error_Msg_N
(Msg
, Main_Unit_Node
);
413 Error_Msg_File_1
:= Fname
;
414 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
417 -- Start of processing for Check_Bad_Body
420 -- Nothing to do if we are only checking syntax, because we don't know
421 -- enough to know if we require or forbid a body in this case.
423 if Operating_Mode
= Check_Syntax
then
427 -- Check for body not allowed
429 if (Main_Kind
= N_Package_Declaration
430 and then not Body_Required
(Main_Unit_Node
))
431 or else (Main_Kind
= N_Generic_Package_Declaration
432 and then not Body_Required
(Main_Unit_Node
))
433 or else Main_Kind
= N_Package_Renaming_Declaration
434 or else Main_Kind
= N_Subprogram_Renaming_Declaration
435 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
436 in N_Generic_Instantiation
438 Sname
:= Unit_Name
(Main_Unit
);
440 -- If we do not already have a body name, then get the body name
441 -- (but how can we have a body name here???)
443 if not Is_Body_Name
(Sname
) then
444 Sname
:= Get_Body_Name
(Sname
);
447 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
448 Src_Ind
:= Load_Source_File
(Fname
);
450 -- Case where body is present and it is not a subunit. Exclude the
451 -- subunit case, because it has nothing to do with the package we are
452 -- compiling. It is illegal for a child unit and a subunit with the
453 -- same expanded name (RM 10.2(9)) to appear together in a partition,
454 -- but there is nothing to stop a compilation environment from having
455 -- both, and the test here simply allows that. If there is an attempt
456 -- to include both in a partition, this is diagnosed at bind time. In
457 -- Ada 83 mode this is not a warning case.
459 -- Note: if weird file names are being used, we can have a situation
460 -- where the file name that supposedly contains body in fact contains
461 -- a spec, or we can't tell what it contains. Skip the error message
464 -- Also ignore body that is nothing but pragma No_Body; (that's the
465 -- whole point of this pragma, to be used this way and to cause the
466 -- body file to be ignored in this context).
468 if Src_Ind
/= No_Source_File
469 and then Get_Expected_Unit_Type
(Fname
) = Expect_Body
470 and then not Source_File_Is_Subunit
(Src_Ind
)
471 and then not Source_File_Is_No_Body
(Src_Ind
)
473 Errout
.Finalize
(Last_Call
=> False);
475 Error_Msg_Unit_1
:= Sname
;
477 -- Ada 83 case of a package body being ignored. This is not an
478 -- error as far as the Ada 83 RM is concerned, but it is almost
479 -- certainly not what is wanted so output a warning. Give this
480 -- message only if there were no errors, since otherwise it may
481 -- be incorrect (we may have misinterpreted a junk spec as not
482 -- needing a body when it really does).
484 if Main_Kind
= N_Package_Declaration
485 and then Ada_Version
= Ada_83
486 and then Operating_Mode
= Generate_Code
487 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
488 and then not Compilation_Errors
491 ("package $$ does not require a body?", Main_Unit_Node
);
492 Error_Msg_File_1
:= Fname
;
493 Error_Msg_N
("body in file{? will be ignored", Main_Unit_Node
);
495 -- Ada 95 cases of a body file present when no body is
496 -- permitted. This we consider to be an error.
499 -- For generic instantiations, we never allow a body
501 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
502 in N_Generic_Instantiation
505 ("generic instantiation for $$ does not allow a body");
507 -- A library unit that is a renaming never allows a body
509 elsif Main_Kind
in N_Renaming_Declaration
then
511 ("renaming declaration for $$ does not allow a body!");
513 -- Remaining cases are packages and generic packages. Here
514 -- we only do the test if there are no previous errors,
515 -- because if there are errors, they may lead us to
516 -- incorrectly believe that a package does not allow a body
517 -- when in fact it does.
519 elsif not Compilation_Errors
then
520 if Main_Kind
= N_Package_Declaration
then
522 ("package $$ does not allow a body!");
524 elsif Main_Kind
= N_Generic_Package_Declaration
then
526 ("generic package $$ does not allow a body!");
535 -------------------------
536 -- Check_Library_Items --
537 -------------------------
539 -- Walk_Library_Items has plenty of assertions, so all we need to do is
540 -- call it, just for these assertions, not actually doing anything else.
542 procedure Check_Library_Items
is
544 procedure Action
(Item
: Node_Id
);
545 -- Action passed to Walk_Library_Items to do nothing
551 procedure Action
(Item
: Node_Id
) is
556 procedure Walk
is new Sem
.Walk_Library_Items
(Action
);
558 -- Start of processing for Check_Library_Items
562 end Check_Library_Items
;
568 procedure Check_Rep_Info
is
570 if List_Representation_Info
/= 0
571 or else List_Representation_Info_Mechanisms
576 ("cannot generate representation information, no code generated");
583 -- Start of processing for Gnat1drv
586 -- This inner block is set up to catch assertion errors and constraint
587 -- errors. Since the code for handling these errors can cause another
588 -- exception to be raised (namely Unrecoverable_Error), we need two
589 -- nested blocks, so that the outer one handles unrecoverable error.
592 -- Initialize all packages. For the most part, these initialization
593 -- calls can be made in any order. Exceptions are as follows:
595 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
596 -- because it initializes a table filled by Scan_Compiler_Arguments.
602 Scan_Compiler_Arguments
;
603 Osint
.Add_Default_Search_Dirs
;
623 Sem_Type
.Init_Interp_Tables
;
625 -- Acquire target parameters from system.ads (source of package System)
630 S
: Source_File_Index
;
634 Name_Buffer
(1 .. 10) := "system.ads";
637 S
:= Load_Source_File
(N
);
639 if S
= No_Source_File
then
641 ("fatal error, run-time library not installed correctly");
642 Write_Line
("cannot locate file system.ads");
643 raise Unrecoverable_Error
;
645 -- Remember source index of system.ads (which was read successfully)
648 System_Source_File_Index
:= S
;
651 Targparm
.Get_Target_Parameters
652 (System_Text
=> Source_Text
(S
),
653 Source_First
=> Source_First
(S
),
654 Source_Last
=> Source_Last
(S
));
656 -- Acquire configuration pragma information from Targparm
658 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
661 Adjust_Global_Switches
;
663 -- Output copyright notice if full list mode unless we have a list
664 -- file, in which case we defer this so that it is output in the file
666 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
667 and then not Debug_Flag_7
671 Write_Str
(Gnat_Version_String
);
673 Write_Str
("Copyright 1992-" & Current_Year
674 & ", Free Software Foundation, Inc.");
678 -- Check we do not have more than one source file, this happens only in
679 -- the case where the driver is called directly, it cannot happen when
680 -- gnat1 is invoked from gcc in the normal case.
682 if Osint
.Number_Of_Files
/= 1 then
685 Osint
.Fail
("you must provide one source file");
687 elsif Usage_Requested
then
691 Original_Operating_Mode
:= Operating_Mode
;
694 -- Exit with errors if the main source could not be parsed
696 if Sinput
.Main_Source_File
= No_Source_File
then
697 Errout
.Finalize
(Last_Call
=> True);
698 Errout
.Output_Messages
;
699 Exit_Program
(E_Errors
);
702 Main_Unit_Node
:= Cunit
(Main_Unit
);
703 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
706 -- Exit if compilation errors detected
708 Errout
.Finalize
(Last_Call
=> False);
710 if Compilation_Errors
then
712 Sem_Ch13
.Validate_Unchecked_Conversions
;
713 Sem_Ch13
.Validate_Address_Clauses
;
714 Sem_Ch13
.Validate_Independence
;
715 Errout
.Output_Messages
;
718 -- Generate ALI file if specially requested
720 if Opt
.Force_ALI_Tree_File
then
721 Write_ALI
(Object
=> False);
725 Errout
.Finalize
(Last_Call
=> True);
726 Exit_Program
(E_Errors
);
729 -- Set Generate_Code on main unit and its spec. We do this even if are
730 -- not generating code, since Lib-Writ uses this to determine which
731 -- units get written in the ali file.
733 Set_Generate_Code
(Main_Unit
);
735 -- If we have a corresponding spec, and it comes from source or it is
736 -- not a generated spec for a child subprogram body, then we need object
737 -- code for the spec unit as well.
739 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
740 and then not Acts_As_Spec
(Main_Unit_Node
)
742 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
743 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
748 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
752 -- Case of no code required to be generated, exit indicating no error
754 if Original_Operating_Mode
= Check_Syntax
then
756 Errout
.Finalize
(Last_Call
=> True);
757 Errout
.Output_Messages
;
762 -- Use a goto instead of calling Exit_Program so that finalization
767 elsif Original_Operating_Mode
= Check_Semantics
then
768 Back_End_Mode
:= Declarations_Only
;
770 -- All remaining cases are cases in which the user requested that code
771 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
772 -- can in fact satisfy this request.
774 -- Cannot generate code if someone has turned off code generation for
775 -- any reason at all. We will try to figure out a reason below.
777 elsif Operating_Mode
/= Generate_Code
then
778 Back_End_Mode
:= Skip
;
780 -- We can generate code for a subprogram body unless there were missing
781 -- subunits. Note that we always generate code for all generic units (a
782 -- change from some previous versions of GNAT).
784 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
785 Back_End_Mode
:= Generate_Object
;
787 -- We can generate code for a package body unless there are subunits
788 -- missing (note that we always generate code for generic units, which
789 -- is a change from some earlier versions of GNAT).
791 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
792 Back_End_Mode
:= Generate_Object
;
794 -- We can generate code for a package declaration or a subprogram
795 -- declaration only if it does not required a body.
797 elsif Nkind_In
(Main_Kind
,
798 N_Package_Declaration
,
799 N_Subprogram_Declaration
)
801 (not Body_Required
(Main_Unit_Node
)
803 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
805 Back_End_Mode
:= Generate_Object
;
807 -- We can generate code for a generic package declaration of a generic
808 -- subprogram declaration only if does not require a body.
810 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
811 N_Generic_Subprogram_Declaration
)
812 and then not Body_Required
(Main_Unit_Node
)
814 Back_End_Mode
:= Generate_Object
;
816 -- Compilation units that are renamings do not require bodies, so we can
817 -- generate code for them.
819 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
820 N_Subprogram_Renaming_Declaration
)
822 Back_End_Mode
:= Generate_Object
;
824 -- Compilation units that are generic renamings do not require bodies
825 -- so we can generate code for them.
827 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
828 Back_End_Mode
:= Generate_Object
;
830 -- It's not an error to generate SCIL for e.g. a spec which has a body
832 elsif CodePeer_Mode
then
833 Back_End_Mode
:= Generate_Object
;
835 -- In all other cases (specs which have bodies, generics, and bodies
836 -- where subunits are missing), we cannot generate code and we generate
837 -- a warning message. Note that generic instantiations are gone at this
838 -- stage since they have been replaced by their instances.
841 Back_End_Mode
:= Skip
;
844 -- At this stage Back_End_Mode is set to indicate if the backend should
845 -- be called to generate code. If it is Skip, then code generation has
846 -- been turned off, even though code was requested by the original
847 -- command. This is not an error from the user point of view, but it is
848 -- an error from the point of view of the gcc driver, so we must exit
849 -- with an error status.
851 -- We generate an informative message (from the gcc point of view, it
852 -- is an error message, but from the users point of view this is not an
853 -- error, just a consequence of compiling something that cannot
856 if Back_End_Mode
= Skip
then
858 Write_Str
("cannot generate code for ");
860 Write_Name
(Unit_File_Name
(Main_Unit
));
862 if Subunits_Missing
then
863 Write_Str
(" (missing subunits)");
866 -- Force generation of ALI file, for backward compatibility
868 Opt
.Force_ALI_Tree_File
:= True;
870 elsif Main_Kind
= N_Subunit
then
871 Write_Str
(" (subunit)");
874 -- Force generation of ALI file, for backward compatibility
876 Opt
.Force_ALI_Tree_File
:= True;
878 elsif Main_Kind
= N_Subprogram_Declaration
then
879 Write_Str
(" (subprogram spec)");
882 -- Generic package body in GNAT implementation mode
884 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
885 Write_Str
(" (predefined generic)");
888 -- Force generation of ALI file, for backward compatibility
890 Opt
.Force_ALI_Tree_File
:= True;
892 -- Only other case is a package spec
895 Write_Str
(" (package spec)");
901 Sem_Ch13
.Validate_Unchecked_Conversions
;
902 Sem_Ch13
.Validate_Address_Clauses
;
903 Sem_Ch13
.Validate_Independence
;
904 Errout
.Finalize
(Last_Call
=> True);
905 Errout
.Output_Messages
;
909 -- Generate ALI file if specially requested, or for missing subunits,
910 -- subunits or predefined generic.
912 if Opt
.Force_ALI_Tree_File
then
913 Write_ALI
(Object
=> False);
919 -- Exit program with error indication, to kill object file
921 Exit_Program
(E_No_Code
);
924 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
925 -- as indicated by Back_Annotate_Rep_Info being set to True.
927 -- We don't call for annotations on a subunit, because to process those
928 -- the back-end requires that the parent(s) be properly compiled.
930 -- Annotation is suppressed for targets where front-end layout is
931 -- enabled, because the front end determines representations.
933 -- Annotation is also suppressed in the case of compiling for a VM,
934 -- since representations are largely symbolic there.
936 if Back_End_Mode
= Declarations_Only
937 and then (not (Back_Annotate_Rep_Info
or Generate_SCIL
)
938 or else Main_Kind
= N_Subunit
939 or else Targparm
.Frontend_Layout_On_Target
940 or else Targparm
.VM_Target
/= No_VM
)
942 Sem_Ch13
.Validate_Unchecked_Conversions
;
943 Sem_Ch13
.Validate_Address_Clauses
;
944 Sem_Ch13
.Validate_Independence
;
945 Errout
.Finalize
(Last_Call
=> True);
946 Errout
.Output_Messages
;
947 Write_ALI
(Object
=> False);
955 -- Ensure that we properly register a dependency on system.ads, since
956 -- even if we do not semantically depend on this, Targparm has read
957 -- system parameters from the system.ads file.
959 Lib
.Writ
.Ensure_System_Dependency
;
961 -- Add dependencies, if any, on preprocessing data file and on
962 -- preprocessing definition file(s).
964 Prepcomp
.Add_Dependencies
;
966 -- Back end needs to explicitly unlock tables it needs to touch
979 -- ???Check_Library_Items under control of a debug flag, because it
980 -- currently does not work if the -gnatn switch (back end inlining) is
983 if Debug_Flag_Dot_WW
then
987 -- Here we call the back end to generate the output code
989 Generating_Code
:= True;
990 Back_End
.Call_Back_End
(Back_End_Mode
);
992 -- Once the backend is complete, we unlock the names table. This call
993 -- allows a few extra entries, needed for example for the file name for
994 -- the library file output.
998 -- Generate the call-graph output of dispatching calls
1000 Exp_CG
.Generate_CG_Output
;
1002 -- Validate unchecked conversions (using the values for size and
1003 -- alignment annotated by the backend where possible).
1005 Sem_Ch13
.Validate_Unchecked_Conversions
;
1007 -- Validate address clauses (again using alignment values annotated
1008 -- by the backend where possible).
1010 Sem_Ch13
.Validate_Address_Clauses
;
1012 -- Validate independence pragmas (again using values annotated by
1013 -- the back end for component layout etc.)
1015 Sem_Ch13
.Validate_Independence
;
1017 -- Now we complete output of errors, rep info and the tree info. These
1018 -- are delayed till now, since it is perfectly possible for gigi to
1019 -- generate errors, modify the tree (in particular by setting flags
1020 -- indicating that elaboration is required, and also to back annotate
1021 -- representation information for List_Rep_Info.
1023 Errout
.Finalize
(Last_Call
=> True);
1024 Errout
.Output_Messages
;
1027 -- Only write the library if the backend did not generate any error
1028 -- messages. Otherwise signal errors to the driver program so that
1029 -- there will be no attempt to generate an object file.
1031 if Compilation_Errors
then
1033 Exit_Program
(E_Errors
);
1036 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
));
1038 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1039 -- Write_ALI may in fact result in further tree decoration from the
1040 -- original tree file. Note that we dump the tree just before generating
1041 -- it, so that the dump will exactly reflect what is written out.
1046 -- Finalize name table and we are all done
1051 -- Handle fatal internal compiler errors
1053 when Rtsfind
.RE_Not_Available
=>
1054 Comperr
.Compiler_Abort
("RE_Not_Available");
1056 when System
.Assertions
.Assert_Failure
=>
1057 Comperr
.Compiler_Abort
("Assert_Failure");
1059 when Constraint_Error
=>
1060 Comperr
.Compiler_Abort
("Constraint_Error");
1062 when Program_Error
=>
1063 Comperr
.Compiler_Abort
("Program_Error");
1065 when Storage_Error
=>
1067 -- Assume this is a bug. If it is real, the message will in any case
1068 -- say Storage_Error, giving a strong hint!
1070 Comperr
.Compiler_Abort
("Storage_Error");
1076 -- The outer exception handles an unrecoverable error
1079 when Unrecoverable_Error
=>
1080 Errout
.Finalize
(Last_Call
=> True);
1081 Errout
.Output_Messages
;
1084 Write_Str
("compilation abandoned");
1087 Set_Standard_Output
;
1090 Exit_Program
(E_Errors
);