1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, 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;
34 with Fname; use Fname;
35 with Fname.UF; use Fname.UF;
37 with Gnatvsn; use Gnatvsn;
41 with Lib.Writ; use Lib.Writ;
43 with Namet; use Namet;
46 with Osint; use Osint;
47 with Output; use Output;
49 with Repinfo; use Repinfo;
59 with Sinfo; use Sinfo;
60 with Sinput.L; use Sinput.L;
62 with Sprint; use Sprint;
64 with Targparm; use Targparm;
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
86 procedure Adjust_Global_Switches;
87 -- There are various interactions between front end switch settings,
88 -- including debug switch settings and target dependent parameters.
89 -- This procedure takes care of properly handling these interactions.
90 -- We do it after scanning out all the switches, that way we are not
91 -- depending on the order in which switches appear.
93 procedure Check_Bad_Body;
94 -- Called to check if the unit we are compiling has a bad body
96 procedure Check_Rep_Info;
97 -- Called when we are not generating code, to check if -gnatR was requested
98 -- and if so, explain that we will not be honoring the request.
100 procedure Check_Library_Items;
101 -- For debugging -- checks the behavior of Walk_Library_Items
102 pragma Warnings (Off, Check_Library_Items);
103 -- In case the call below is commented out
105 ----------------------------
106 -- Adjust_Global_Switches --
107 ----------------------------
109 procedure Adjust_Global_Switches is
112 -- Set ASIS mode if -gnatt and -gnatc are set
114 if Operating_Mode = Check_Semantics and then Tree_Output then
117 -- Turn off inlining in ASIS mode, since ASIS cannot handle the extra
118 -- information in the trees caused by inlining being active.
120 -- More specifically, the tree seems to malformed from the ASIS point
121 -- of view if -gnatc and -gnatn appear together ???
123 Inline_Active := False;
125 -- Turn off inspector mode in ASIS mode. For reasons that need
126 -- clearer documentation, Inspector cannot function in this mode ???
128 Inspector_Mode := False;
131 -- Inspeector mode requires back-end rep info and also needs to disable
132 -- front-end inlining (but -gnatn does not need to be disabled).
134 if Inspector_Mode then
135 Back_Annotate_Rep_Info := True;
136 Front_End_Inlining := False;
139 -- Set Configurable_Run_Time mode if system.ads flag set
141 if Targparm.Configurable_Run_Time_On_Target or Debug_Flag_YY then
142 Configurable_Run_Time_Mode := True;
145 -- Set -gnatR3m mode if debug flag A set
147 if Debug_Flag_AA then
148 Back_Annotate_Rep_Info := True;
149 List_Representation_Info := 1;
150 List_Representation_Info_Mechanisms := True;
153 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
155 if Debug_Flag_Dot_A then
156 Ttypes.Target_Strict_Alignment := True;
159 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
160 -- is enabled. The front end's layout phase currently treats types that
161 -- have discriminant-dependent arrays as not being static even when a
162 -- discriminant constraint on the type is static, and this leads to
163 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
165 if Debug_Flag_Dot_T or else Frontend_Layout_On_Target then
166 Static_Dispatch_Tables := False;
169 -- Flip endian mode if -gnatd8 set
172 Ttypes.Bytes_Big_Endian := not Ttypes.Bytes_Big_Endian;
175 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
176 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
177 -- before doing this, so we know if we are in real openVMS or not!
179 Opt.True_VMS_Target := Targparm.OpenVMS_On_Target;
182 Targparm.OpenVMS_On_Target := True;
183 Hostparm.OpenVMS := True;
186 -- Activate front end layout if debug flag -gnatdF is set
188 if Debug_Flag_FF then
189 Targparm.Frontend_Layout_On_Target := True;
192 -- Set and check exception mechnism
194 if Targparm.ZCX_By_Default_On_Target then
195 if Targparm.GCC_ZCX_Support_On_Target then
196 Exception_Mechanism := Back_End_Exceptions;
198 Osint.Fail ("Zero Cost Exceptions not supported on this target");
202 -- Set proper status for overflow checks. We turn on overflow checks
203 -- if -gnatp was not specified, and either -gnato is set or the back
204 -- end takes care of overflow checks. Otherwise we suppress overflow
205 -- checks by default (since front end checks are expensive).
207 if not Opt.Suppress_Checks
208 and then (Opt.Enable_Overflow_Checks
210 (Targparm.Backend_Divide_Checks_On_Target
212 Targparm.Backend_Overflow_Checks_On_Target))
214 Suppress_Options (Overflow_Check) := False;
216 Suppress_Options (Overflow_Check) := True;
218 end Adjust_Global_Switches;
224 procedure Check_Bad_Body is
225 Sname : Unit_Name_Type;
226 Src_Ind : Source_File_Index;
227 Fname : File_Name_Type;
229 procedure Bad_Body_Error (Msg : String);
230 -- Issue message for bad body found
236 procedure Bad_Body_Error (Msg : String) is
238 Error_Msg_N (Msg, Main_Unit_Node);
239 Error_Msg_File_1 := Fname;
240 Error_Msg_N ("remove incorrect body in file{!", Main_Unit_Node);
243 -- Start of processing for Check_Bad_Body
246 -- Nothing to do if we are only checking syntax, because we don't know
247 -- enough to know if we require or forbid a body in this case.
249 if Operating_Mode = Check_Syntax then
253 -- Check for body not allowed
255 if (Main_Kind = N_Package_Declaration
256 and then not Body_Required (Main_Unit_Node))
257 or else (Main_Kind = N_Generic_Package_Declaration
258 and then not Body_Required (Main_Unit_Node))
259 or else Main_Kind = N_Package_Renaming_Declaration
260 or else Main_Kind = N_Subprogram_Renaming_Declaration
261 or else Nkind (Original_Node (Unit (Main_Unit_Node)))
262 in N_Generic_Instantiation
264 Sname := Unit_Name (Main_Unit);
266 -- If we do not already have a body name, then get the body name
267 -- (but how can we have a body name here ???)
269 if not Is_Body_Name (Sname) then
270 Sname := Get_Body_Name (Sname);
273 Fname := Get_File_Name (Sname, Subunit => False);
274 Src_Ind := Load_Source_File (Fname);
276 -- Case where body is present and it is not a subunit. Exclude
277 -- the subunit case, because it has nothing to do with the
278 -- package we are compiling. It is illegal for a child unit and a
279 -- subunit with the same expanded name (RM 10.2(9)) to appear
280 -- together in a partition, but there is nothing to stop a
281 -- compilation environment from having both, and the test here
282 -- simply allows that. If there is an attempt to include both in
283 -- a partition, this is diagnosed at bind time. In Ada 83 mode
284 -- this is not a warning case.
286 -- Note: if weird file names are being used, we can have
287 -- situation where the file name that supposedly contains body,
288 -- in fact contains a spec, or we can't tell what it contains.
289 -- Skip the error message in these cases.
291 -- Also ignore body that is nothing but pragma No_Body; (that's the
292 -- whole point of this pragma, to be used this way and to cause the
293 -- body file to be ignored in this context).
295 if Src_Ind /= No_Source_File
296 and then Get_Expected_Unit_Type (Fname) = Expect_Body
297 and then not Source_File_Is_Subunit (Src_Ind)
298 and then not Source_File_Is_No_Body (Src_Ind)
300 Errout.Finalize (Last_Call => False);
302 Error_Msg_Unit_1 := Sname;
304 -- Ada 83 case of a package body being ignored. This is not an
305 -- error as far as the Ada 83 RM is concerned, but it is almost
306 -- certainly not what is wanted so output a warning. Give this
307 -- message only if there were no errors, since otherwise it may
308 -- be incorrect (we may have misinterpreted a junk spec as not
309 -- needing a body when it really does).
311 if Main_Kind = N_Package_Declaration
312 and then Ada_Version = Ada_83
313 and then Operating_Mode = Generate_Code
314 and then Distribution_Stub_Mode /= Generate_Caller_Stub_Body
315 and then not Compilation_Errors
318 ("package $$ does not require a body?", Main_Unit_Node);
319 Error_Msg_File_1 := Fname;
320 Error_Msg_N ("body in file{? will be ignored", Main_Unit_Node);
322 -- Ada 95 cases of a body file present when no body is
323 -- permitted. This we consider to be an error.
326 -- For generic instantiations, we never allow a body
328 if Nkind (Original_Node (Unit (Main_Unit_Node)))
329 in N_Generic_Instantiation
332 ("generic instantiation for $$ does not allow a body");
334 -- A library unit that is a renaming never allows a body
336 elsif Main_Kind in N_Renaming_Declaration then
338 ("renaming declaration for $$ does not allow a body!");
340 -- Remaining cases are packages and generic packages. Here
341 -- we only do the test if there are no previous errors,
342 -- because if there are errors, they may lead us to
343 -- incorrectly believe that a package does not allow a body
344 -- when in fact it does.
346 elsif not Compilation_Errors then
347 if Main_Kind = N_Package_Declaration then
349 ("package $$ does not allow a body!");
351 elsif Main_Kind = N_Generic_Package_Declaration then
353 ("generic package $$ does not allow a body!");
366 procedure Check_Rep_Info is
368 if List_Representation_Info /= 0
369 or else List_Representation_Info_Mechanisms
374 ("cannot generate representation information, no code generated");
381 -------------------------
382 -- Check_Library_Items --
383 -------------------------
385 -- Walk_Library_Items has plenty of assertions, so all we need to do is
386 -- call it, just for these assertions, not actually doing anything else.
388 procedure Check_Library_Items is
390 procedure Action (Item : Node_Id);
391 -- Action passed to Walk_Library_Items to do nothing
397 procedure Action (Item : Node_Id) is
402 procedure Walk is new Sem.Walk_Library_Items (Action);
404 -- Start of processing for Check_Library_Items
408 end Check_Library_Items;
410 -- Start of processing for Gnat1drv
413 -- This inner block is set up to catch assertion errors and constraint
414 -- errors. Since the code for handling these errors can cause another
415 -- exception to be raised (namely Unrecoverable_Error), we need two
416 -- nested blocks, so that the outer one handles unrecoverable error.
419 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
420 -- because it initializes a table filled by Scan_Compiler_Arguments.
426 Scan_Compiler_Arguments;
427 Osint.Add_Default_Search_Dirs;
445 Sem_Type.Init_Interp_Tables;
447 -- Acquire target parameters from system.ads (source of package System)
452 S : Source_File_Index;
456 Name_Buffer (1 .. 10) := "system.ads";
459 S := Load_Source_File (N);
461 if S = No_Source_File then
463 ("fatal error, run-time library not installed correctly");
465 ("cannot locate file system.ads");
466 raise Unrecoverable_Error;
468 -- Remember source index of system.ads (which was read successfully)
471 System_Source_File_Index := S;
474 Targparm.Get_Target_Parameters
475 (System_Text => Source_Text (S),
476 Source_First => Source_First (S),
477 Source_Last => Source_Last (S));
479 -- Acquire configuration pragma information from Targparm
481 Restrict.Restrictions := Targparm.Restrictions_On_Target;
484 Adjust_Global_Switches;
486 -- Output copyright notice if full list mode unless we have a list
487 -- file, in which case we defer this so that it is output in the file
489 if (Verbose_Mode or else (Full_List and then Full_List_File_Name = null))
490 and then not Debug_Flag_7
494 Write_Str (Gnat_Version_String);
496 Write_Str ("Copyright 1992-" &
498 ", Free Software Foundation, Inc.");
502 -- Check we do not have more than one source file, this happens only in
503 -- the case where the driver is called directly, it cannot happen when
504 -- gnat1 is invoked from gcc in the normal case.
506 if Osint.Number_Of_Files /= 1 then
509 Osint.Fail ("you must provide one source file");
511 elsif Usage_Requested then
515 Original_Operating_Mode := Operating_Mode;
518 -- Exit with errors if the main source could not be parsed
520 if Sinput.Main_Source_File = No_Source_File then
521 Errout.Finalize (Last_Call => True);
522 Errout.Output_Messages;
523 Exit_Program (E_Errors);
526 Main_Unit_Node := Cunit (Main_Unit);
527 Main_Kind := Nkind (Unit (Main_Unit_Node));
530 -- Exit if compilation errors detected
532 Errout.Finalize (Last_Call => False);
534 if Compilation_Errors then
536 Sem_Ch13.Validate_Unchecked_Conversions;
537 Sem_Ch13.Validate_Address_Clauses;
538 Errout.Output_Messages;
541 -- Generate ALI file if specially requested
543 if Opt.Force_ALI_Tree_File then
544 Write_ALI (Object => False);
548 Errout.Finalize (Last_Call => True);
549 Exit_Program (E_Errors);
552 -- Set Generate_Code on main unit and its spec. We do this even if are
553 -- not generating code, since Lib-Writ uses this to determine which
554 -- units get written in the ali file.
556 Set_Generate_Code (Main_Unit);
558 -- If we have a corresponding spec, and it comes from source
559 -- or it is not a generated spec for a child subprogram body,
560 -- then we need object code for the spec unit as well.
562 if Nkind (Unit (Main_Unit_Node)) in N_Unit_Body
563 and then not Acts_As_Spec (Main_Unit_Node)
565 if Nkind (Unit (Main_Unit_Node)) = N_Subprogram_Body
566 and then not Comes_From_Source (Library_Unit (Main_Unit_Node))
571 (Get_Cunit_Unit_Number (Library_Unit (Main_Unit_Node)));
575 -- Case of no code required to be generated, exit indicating no error
577 if Original_Operating_Mode = Check_Syntax then
579 Errout.Finalize (Last_Call => True);
580 Errout.Output_Messages;
585 -- Use a goto instead of calling Exit_Program so that finalization
590 elsif Original_Operating_Mode = Check_Semantics then
591 Back_End_Mode := Declarations_Only;
593 -- All remaining cases are cases in which the user requested that code
594 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if
595 -- we can in fact satisfy this request.
597 -- Cannot generate code if someone has turned off code generation for
598 -- any reason at all. We will try to figure out a reason below.
600 elsif Operating_Mode /= Generate_Code then
601 Back_End_Mode := Skip;
603 -- We can generate code for a subprogram body unless there were missing
604 -- subunits. Note that we always generate code for all generic units (a
605 -- change from some previous versions of GNAT).
607 elsif Main_Kind = N_Subprogram_Body
608 and then not Subunits_Missing
610 Back_End_Mode := Generate_Object;
612 -- We can generate code for a package body unless there are subunits
613 -- missing (note that we always generate code for generic units, which
614 -- is a change from some earlier versions of GNAT).
616 elsif Main_Kind = N_Package_Body
617 and then not Subunits_Missing
619 Back_End_Mode := Generate_Object;
621 -- We can generate code for a package declaration or a subprogram
622 -- declaration only if it does not required a body.
624 elsif (Main_Kind = N_Package_Declaration
626 Main_Kind = N_Subprogram_Declaration)
628 (not Body_Required (Main_Unit_Node)
630 Distribution_Stub_Mode = Generate_Caller_Stub_Body)
632 Back_End_Mode := Generate_Object;
634 -- We can generate code for a generic package declaration of a generic
635 -- subprogram declaration only if does not require a body.
637 elsif (Main_Kind = N_Generic_Package_Declaration
639 Main_Kind = N_Generic_Subprogram_Declaration)
640 and then not Body_Required (Main_Unit_Node)
642 Back_End_Mode := Generate_Object;
644 -- Compilation units that are renamings do not require bodies,
645 -- so we can generate code for them.
647 elsif Main_Kind = N_Package_Renaming_Declaration
648 or else Main_Kind = N_Subprogram_Renaming_Declaration
650 Back_End_Mode := Generate_Object;
652 -- Compilation units that are generic renamings do not require bodies
653 -- so we can generate code for them.
655 elsif Main_Kind in N_Generic_Renaming_Declaration then
656 Back_End_Mode := Generate_Object;
658 -- In all other cases (specs which have bodies, generics, and bodies
659 -- where subunits are missing), we cannot generate code and we generate
660 -- a warning message. Note that generic instantiations are gone at this
661 -- stage since they have been replaced by their instances.
664 Back_End_Mode := Skip;
667 -- At this stage Back_End_Mode is set to indicate if the backend should
668 -- be called to generate code. If it is Skip, then code generation has
669 -- been turned off, even though code was requested by the original
670 -- command. This is not an error from the user point of view, but it is
671 -- an error from the point of view of the gcc driver, so we must exit
672 -- with an error status.
674 -- We generate an informative message (from the gcc point of view, it
675 -- is an error message, but from the users point of view this is not an
676 -- error, just a consequence of compiling something that cannot
679 if Back_End_Mode = Skip then
681 Write_Str ("cannot generate code for ");
683 Write_Name (Unit_File_Name (Main_Unit));
685 if Subunits_Missing then
686 Write_Str (" (missing subunits)");
688 Write_Str ("to check parent unit");
690 elsif Main_Kind = N_Subunit then
691 Write_Str (" (subunit)");
693 Write_Str ("to check subunit");
695 elsif Main_Kind = N_Subprogram_Declaration then
696 Write_Str (" (subprogram spec)");
698 Write_Str ("to check subprogram spec");
700 -- Generic package body in GNAT implementation mode
702 elsif Main_Kind = N_Package_Body and then GNAT_Mode then
703 Write_Str (" (predefined generic)");
705 Write_Str ("to check predefined generic");
707 -- Only other case is a package spec
710 Write_Str (" (package spec)");
712 Write_Str ("to check package spec");
715 Write_Str (" for errors, use ");
717 if Hostparm.OpenVMS then
718 Write_Str ("/NOLOAD");
720 Write_Str ("-gnatc");
726 Sem_Ch13.Validate_Unchecked_Conversions;
727 Sem_Ch13.Validate_Address_Clauses;
728 Errout.Finalize (Last_Call => True);
729 Errout.Output_Messages;
732 Write_ALI (Object => False);
736 -- Exit program with error indication, to kill object file
738 Exit_Program (E_No_Code);
741 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also
742 -- set as indicated by Back_Annotate_Rep_Info being set to True.
744 -- We don't call for annotations on a subunit, because to process those
745 -- the back-end requires that the parent(s) be properly compiled.
747 -- Annotation is suppressed for targets where front-end layout is
748 -- enabled, because the front end determines representations.
750 -- Annotation is also suppressed in the case of compiling for
751 -- a VM, since representations are largely symbolic there.
753 if Back_End_Mode = Declarations_Only
754 and then (not Back_Annotate_Rep_Info
755 or else Main_Kind = N_Subunit
756 or else Targparm.Frontend_Layout_On_Target
757 or else Targparm.VM_Target /= No_VM)
759 Sem_Ch13.Validate_Unchecked_Conversions;
760 Sem_Ch13.Validate_Address_Clauses;
761 Errout.Finalize (Last_Call => True);
762 Errout.Output_Messages;
763 Write_ALI (Object => False);
771 -- Ensure that we properly register a dependency on system.ads, since
772 -- even if we do not semantically depend on this, Targparm has read
773 -- system parameters from the system.ads file.
775 Lib.Writ.Ensure_System_Dependency;
777 -- Add dependencies, if any, on preprocessing data file and on
778 -- preprocessing definition file(s).
780 Prepcomp.Add_Dependencies;
782 -- Back end needs to explicitly unlock tables it needs to touch
795 -- ???Check_Library_Items under control of a debug flag, because it
796 -- currently does not work if the -gnatn switch (back end inlining) is
799 if Debug_Flag_Dot_WW then
803 -- Here we call the back end to generate the output code
805 Generating_Code := True;
806 Back_End.Call_Back_End (Back_End_Mode);
808 -- Once the backend is complete, we unlock the names table. This call
809 -- allows a few extra entries, needed for example for the file name for
810 -- the library file output.
814 -- Validate unchecked conversions (using the values for size and
815 -- alignment annotated by the backend where possible).
817 Sem_Ch13.Validate_Unchecked_Conversions;
819 -- Validate address clauses (again using alignment values annotated
820 -- by the backend where possible).
822 Sem_Ch13.Validate_Address_Clauses;
824 -- Now we complete output of errors, rep info and the tree info. These
825 -- are delayed till now, since it is perfectly possible for gigi to
826 -- generate errors, modify the tree (in particular by setting flags
827 -- indicating that elaboration is required, and also to back annotate
828 -- representation information for List_Rep_Info.
830 Errout.Finalize (Last_Call => True);
831 Errout.Output_Messages;
834 -- Only write the library if the backend did not generate any error
835 -- messages. Otherwise signal errors to the driver program so that
836 -- there will be no attempt to generate an object file.
838 if Compilation_Errors then
840 Exit_Program (E_Errors);
843 Write_ALI (Object => (Back_End_Mode = Generate_Object));
845 -- Generate the ASIS tree after writing the ALI file, since in ASIS
846 -- mode, Write_ALI may in fact result in further tree decoration from
847 -- the original tree file. Note that we dump the tree just before
848 -- generating it, so that the dump will exactly reflect what is written
854 -- Finalize name table and we are all done
859 -- Handle fatal internal compiler errors
861 when Rtsfind.RE_Not_Available =>
862 Comperr.Compiler_Abort ("RE_Not_Available");
864 when System.Assertions.Assert_Failure =>
865 Comperr.Compiler_Abort ("Assert_Failure");
867 when Constraint_Error =>
868 Comperr.Compiler_Abort ("Constraint_Error");
870 when Program_Error =>
871 Comperr.Compiler_Abort ("Program_Error");
873 when Storage_Error =>
875 -- Assume this is a bug. If it is real, the message will in any case
876 -- say Storage_Error, giving a strong hint!
878 Comperr.Compiler_Abort ("Storage_Error");
884 -- The outer exception handles an unrecoverable error
887 when Unrecoverable_Error =>
888 Errout.Finalize (Last_Call => True);
889 Errout.Output_Messages;
892 Write_Str ("compilation abandoned");
898 Exit_Program (E_Errors);