1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2012, 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 Exp_Ch6; use Exp_Ch6;
36 with Fname; use Fname;
37 with Fname.UF; use Fname.UF;
39 with Gnatvsn; use Gnatvsn;
43 with Lib.Writ; use Lib.Writ;
45 with Namet; use Namet;
48 with Osint; use Osint;
49 with Output; use Output;
52 with Repinfo; use Repinfo;
54 with Rident; use Rident;
64 with Sinfo; use Sinfo;
65 with Sinput.L; use Sinput.L;
67 with Sprint; use Sprint;
69 with Stylesw; use Stylesw;
70 with Targparm; use Targparm;
72 with Treepr; use Treepr;
74 with Types; use Types;
75 with Uintp; use Uintp;
76 with Uname; use Uname;
79 with Validsw; use Validsw;
81 with System.Assertions;
84 Main_Unit_Node : Node_Id;
85 -- Compilation unit node for main unit
87 Main_Kind : Node_Kind;
88 -- Kind of main compilation unit node
90 Back_End_Mode : Back_End.Back_End_Mode_Type;
91 -- Record back end mode
93 procedure Adjust_Global_Switches;
94 -- There are various interactions between front end switch settings,
95 -- including debug switch settings and target dependent parameters.
96 -- This procedure takes care of properly handling these interactions.
97 -- We do it after scanning out all the switches, so that we are not
98 -- depending on the order in which switches appear.
100 procedure Check_Bad_Body;
101 -- Called to check if the unit we are compiling has a bad body
103 procedure Check_Rep_Info;
104 -- Called when we are not generating code, to check if -gnatR was requested
105 -- and if so, explain that we will not be honoring the request.
107 ----------------------------
108 -- Adjust_Global_Switches --
109 ----------------------------
111 procedure Adjust_Global_Switches is
113 -- Debug flag -gnatd.I is a synonym for Generate_SCIL and requires code
116 if Debug_Flag_Dot_II and then Operating_Mode = Generate_Code then
117 Generate_SCIL := True;
120 -- Disable CodePeer_Mode in Check_Syntax, since we need front-end
123 if Operating_Mode = Check_Syntax then
124 CodePeer_Mode := False;
127 -- Set ASIS mode if -gnatt and -gnatc are set
129 if Operating_Mode = Check_Semantics and then Tree_Output then
132 -- Turn off inlining in ASIS mode, since ASIS cannot handle the extra
133 -- information in the trees caused by inlining being active.
135 -- More specifically, the tree seems to be malformed from the ASIS
136 -- point of view if -gnatc and -gnatn appear together???
138 Inline_Active := False;
140 -- Turn off SCIL generation and CodePeer mode in semantics mode,
141 -- since SCIL requires front-end expansion.
143 Generate_SCIL := False;
144 CodePeer_Mode := False;
147 -- SCIL mode needs to disable front-end inlining since the generated
148 -- trees (in particular order and consistency between specs compiled
149 -- as part of a main unit or as part of a with-clause) are causing
152 if Generate_SCIL then
153 Front_End_Inlining := False;
156 -- Tune settings for optimal SCIL generation in CodePeer mode
158 if CodePeer_Mode then
160 -- Turn off inlining, confuses CodePeer output and gains nothing
162 Front_End_Inlining := False;
163 Inline_Active := False;
165 -- Disable front-end optimizations, to keep the tree as close to the
166 -- source code as possible, and also to avoid inconsistencies between
167 -- trees when using different optimization switches.
169 Optimization_Level := 0;
171 -- Enable some restrictions systematically to simplify the generated
172 -- code (and ease analysis). Note that restriction checks are also
173 -- disabled in CodePeer mode, see Restrict.Check_Restriction, and
174 -- user specified Restrictions pragmas are ignored, see
175 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
177 Restrict.Restrictions.Set (No_Initialize_Scalars) := True;
178 Restrict.Restrictions.Set (No_Task_Hierarchy) := True;
179 Restrict.Restrictions.Set (No_Abort_Statements) := True;
180 Restrict.Restrictions.Set (Max_Asynchronous_Select_Nesting) := True;
181 Restrict.Restrictions.Value (Max_Asynchronous_Select_Nesting) := 0;
183 -- Suppress division by zero and access checks since they are handled
184 -- implicitly by CodePeer.
186 -- Turn off dynamic elaboration checks: generates inconsistencies in
187 -- trees between specs compiled as part of a main unit or as part of
190 -- Turn off alignment checks: these cannot be proved statically by
191 -- CodePeer and generate false positives.
193 -- Enable all other language checks
195 Suppress_Options.Suppress :=
196 (Access_Check => True,
197 Alignment_Check => True,
198 Division_Check => True,
199 Elaboration_Check => True,
202 Dynamic_Elaboration_Checks := False;
204 -- Set STRICT mode for overflow checks if not set explicitly. This
205 -- prevents suppressing of overflow checks by default, in code down
208 if Suppress_Options.Overflow_Mode_General = Not_Set then
209 Suppress_Options.Overflow_Mode_General := Strict;
210 Suppress_Options.Overflow_Mode_Assertions := Strict;
213 -- Kill debug of generated code, since it messes up sloc values
215 Debug_Generated_Code := False;
217 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
218 -- Do we really need to spend time generating xref in CodePeer
219 -- mode??? Consider setting Xref_Active to False.
223 -- Polling mode forced off, since it generates confusing junk
225 Polling_Required := False;
227 -- Set operating mode to Generate_Code to benefit from full front-end
228 -- expansion (e.g. generics).
230 Operating_Mode := Generate_Code;
232 -- We need SCIL generation of course
234 Generate_SCIL := True;
236 -- Enable assertions and debug pragmas, since they give CodePeer
237 -- valuable extra information.
239 Assertions_Enabled := True;
240 Debug_Pragmas_Enabled := True;
242 -- Disable all simple value propagation. This is an optimization
243 -- which is valuable for code optimization, and also for generation
244 -- of compiler warnings, but these are being turned off by default,
245 -- and CodePeer generates better messages (referencing original
246 -- variables) this way.
248 Debug_Flag_MM := True;
250 -- Set normal RM validity checking, and checking of IN OUT parameters
251 -- (this might give CodePeer more useful checks to analyze, to be
252 -- confirmed???). All other validity checking is turned off, since
253 -- this can generate very complex trees that only confuse CodePeer
254 -- and do not bring enough useful info.
256 Reset_Validity_Check_Options;
257 Validity_Check_Default := True;
258 Validity_Check_In_Out_Params := True;
259 Validity_Check_In_Params := True;
261 -- Turn off style check options since we are not interested in any
262 -- front-end warnings when we are getting CodePeer output.
264 Reset_Style_Check_Options;
266 -- Always perform semantics and generate ali files in CodePeer mode,
267 -- so that a gnatmake -c -k will proceed further when possible.
269 Force_ALI_Tree_File := True;
270 Try_Semantics := True;
273 -- Set switches for formal verification mode
275 if Debug_Flag_Dot_VV then
276 Formal_Extensions := True;
279 if Debug_Flag_Dot_FF then
282 -- Set strict standard interpretation of compiler permissions
284 if Debug_Flag_Dot_DD then
285 Strict_Alfa_Mode := True;
288 -- Turn off inlining, which would confuse formal verification output
291 Front_End_Inlining := False;
292 Inline_Active := False;
294 -- Disable front-end optimizations, to keep the tree as close to the
295 -- source code as possible, and also to avoid inconsistencies between
296 -- trees when using different optimization switches.
298 Optimization_Level := 0;
300 -- Enable some restrictions systematically to simplify the generated
301 -- code (and ease analysis). Note that restriction checks are also
302 -- disabled in Alfa mode, see Restrict.Check_Restriction, and user
303 -- specified Restrictions pragmas are ignored, see
304 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
306 Restrict.Restrictions.Set (No_Initialize_Scalars) := True;
308 -- Note: at this point we used to suppress various checks, but that
309 -- is not what we want. We need the semantic processing for these
310 -- checks (which will set flags like Do_Overflow_Check, showing the
311 -- points at which potential checks are required semantically). We
312 -- don't want the expansion associated with these checks, but that
313 -- happens anyway because this expansion is simply not done in the
314 -- Alfa version of the expander.
316 -- Turn off dynamic elaboration checks: generates inconsistencies in
317 -- trees between specs compiled as part of a main unit or as part of
320 Dynamic_Elaboration_Checks := False;
322 -- Set STRICT mode for overflow checks if not set explicitly. This
323 -- prevents suppressing of overflow checks by default, in code down
326 if Suppress_Options.Overflow_Mode_General = Not_Set then
327 Suppress_Options.Overflow_Mode_General := Strict;
328 Suppress_Options.Overflow_Mode_Assertions := Strict;
331 -- Kill debug of generated code, since it messes up sloc values
333 Debug_Generated_Code := False;
335 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
336 -- as it is needed for computing effects of subprograms in the formal
337 -- verification backend.
341 -- Polling mode forced off, since it generates confusing junk
343 Polling_Required := False;
345 -- Set operating mode to Generate_Code, but full front-end expansion
346 -- is not desirable in Alfa mode, so a light expansion is performed
349 Operating_Mode := Generate_Code;
353 Debug_Flag_HH := True;
355 -- Disable Expressions_With_Actions nodes
357 -- The gnat2why backend does not deal with Expressions_With_Actions
358 -- in all places (in particular assertions). It is difficult to
359 -- determine in the frontend which cases are allowed, so we disable
360 -- Expressions_With_Actions entirely. Even in the cases where
361 -- gnat2why deals with Expressions_With_Actions, it is easier to
362 -- deal with the original constructs (quantified, conditional and
363 -- case expressions) instead of the rewritten ones.
365 Use_Expression_With_Actions := False;
367 -- Enable assertions and debug pragmas, since they give valuable
368 -- extra information for formal verification.
370 Assertions_Enabled := True;
371 Debug_Pragmas_Enabled := True;
373 -- Turn off style check options since we are not interested in any
374 -- front-end warnings when we are getting Alfa output.
376 Reset_Style_Check_Options;
378 -- Suppress compiler warnings, since what we are interested in here
379 -- is what formal verification can find out.
381 Warning_Mode := Suppress;
383 -- Suppress the generation of name tables for enumerations, which are
384 -- not needed for formal verification, and fall outside the Alfa
385 -- subset (use of pointers).
387 Global_Discard_Names := True;
389 -- Suppress the expansion of tagged types and dispatching calls,
390 -- which lead to the generation of non-Alfa code (use of pointers),
391 -- which is more complex to formally verify than the original source.
393 Tagged_Type_Expansion := False;
396 -- Set Configurable_Run_Time mode if system.ads flag set
398 if Targparm.Configurable_Run_Time_On_Target or Debug_Flag_YY then
399 Configurable_Run_Time_Mode := True;
402 -- Set -gnatR3m mode if debug flag A set
404 if Debug_Flag_AA then
405 Back_Annotate_Rep_Info := True;
406 List_Representation_Info := 1;
407 List_Representation_Info_Mechanisms := True;
410 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
412 if Debug_Flag_Dot_A then
413 Ttypes.Target_Strict_Alignment := True;
416 -- Increase size of allocated entities if debug flag -gnatd.N is set
418 if Debug_Flag_Dot_NN then
419 Atree.Num_Extension_Nodes := Atree.Num_Extension_Nodes + 1;
422 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
423 -- is enabled. The front end's layout phase currently treats types that
424 -- have discriminant-dependent arrays as not being static even when a
425 -- discriminant constraint on the type is static, and this leads to
426 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
428 if Debug_Flag_Dot_T or else Frontend_Layout_On_Target then
429 Static_Dispatch_Tables := False;
432 -- Flip endian mode if -gnatd8 set
435 Ttypes.Bytes_Big_Endian := not Ttypes.Bytes_Big_Endian;
438 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
439 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
440 -- before doing this, so we know if we are in real OpenVMS or not!
442 Opt.True_VMS_Target := Targparm.OpenVMS_On_Target;
445 Targparm.OpenVMS_On_Target := True;
446 Hostparm.OpenVMS := True;
449 -- Activate front end layout if debug flag -gnatdF is set
451 if Debug_Flag_FF then
452 Targparm.Frontend_Layout_On_Target := True;
455 -- Set and check exception mechanism
457 if Targparm.ZCX_By_Default_On_Target then
458 Exception_Mechanism := Back_End_Exceptions;
461 -- Set proper status for overflow check mechanism
463 -- If already set (by -gnato or above in Alfa or CodePeer mode) then we
464 -- have nothing to do.
466 if Opt.Suppress_Options.Overflow_Mode_General /= Not_Set then
469 -- Otherwise set overflow mode defaults
472 -- Otherwise set overflow checks off by default
474 Suppress_Options.Suppress (Overflow_Check) := True;
476 -- Set appropriate default overflow handling mode. Note: at present
477 -- we set STRICT in all three of the following cases. They are
478 -- separated because in the future we may make different choices.
480 -- By default set STRICT mode if -gnatg in effect
483 Suppress_Options.Overflow_Mode_General := Strict;
484 Suppress_Options.Overflow_Mode_Assertions := Strict;
486 -- If we have backend divide and overflow checks, then by default
487 -- overflow checks are STRICT. Historically this code used to also
488 -- activate overflow checks, although no target currently has these
489 -- flags set, so this was dead code anyway.
491 elsif Targparm.Backend_Divide_Checks_On_Target
493 Targparm.Backend_Overflow_Checks_On_Target
495 Suppress_Options.Overflow_Mode_General := Strict;
496 Suppress_Options.Overflow_Mode_Assertions := Strict;
498 -- Otherwise for now, default is STRICT mode. This may change in the
499 -- future, but for now this is the compatible behavior with previous
503 Suppress_Options.Overflow_Mode_General := Strict;
504 Suppress_Options.Overflow_Mode_Assertions := Strict;
508 -- Set default for atomic synchronization. As this synchronization
509 -- between atomic accesses can be expensive, and not typically needed
510 -- on some targets, an optional target parameter can turn the option
511 -- off. Note Atomic Synchronization is implemented as check.
513 Suppress_Options.Suppress (Atomic_Synchronization) :=
514 not Atomic_Sync_Default;
516 -- Set switch indicating if we can use N_Expression_With_Actions
518 -- Debug flag -gnatd.X decisively sets usage on
520 if Debug_Flag_Dot_XX then
521 Use_Expression_With_Actions := True;
523 -- Debug flag -gnatd.Y decisively sets usage off
525 elsif Debug_Flag_Dot_YY then
526 Use_Expression_With_Actions := False;
528 -- Otherwise this feature is implemented, so we allow its use
531 Use_Expression_With_Actions := True;
534 -- Set switch indicating if back end can handle limited types, and
535 -- guarantee that no incorrect copies are made (e.g. in the context
536 -- of an if or case expression).
538 -- Debug flag -gnatd.L decisively sets usage on
540 if Debug_Flag_Dot_LL then
541 Back_End_Handles_Limited_Types := True;
543 -- If no debug flag, usage off for AAMP, VM, SCIL cases
546 or else VM_Target /= No_VM
547 or else Generate_SCIL
549 Back_End_Handles_Limited_Types := False;
551 -- Otherwise normal gcc back end, for now still turn flag off by
552 -- default, since there are unresolved problems in the front end.
555 Back_End_Handles_Limited_Types := False;
558 -- If the inlining level has not been set by the user, compute it from
559 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
561 if Inline_Level = 0 then
562 if Optimization_Level < 3 then
569 -- Finally capture adjusted value of Suppress_Options as the initial
570 -- value for Scope_Suppress, which will be modified as we move from
571 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
573 Sem.Scope_Suppress := Opt.Suppress_Options;
574 end Adjust_Global_Switches;
580 procedure Check_Bad_Body is
581 Sname : Unit_Name_Type;
582 Src_Ind : Source_File_Index;
583 Fname : File_Name_Type;
585 procedure Bad_Body_Error (Msg : String);
586 -- Issue message for bad body found
592 procedure Bad_Body_Error (Msg : String) is
594 Error_Msg_N (Msg, Main_Unit_Node);
595 Error_Msg_File_1 := Fname;
596 Error_Msg_N ("remove incorrect body in file{!", Main_Unit_Node);
599 -- Start of processing for Check_Bad_Body
602 -- Nothing to do if we are only checking syntax, because we don't know
603 -- enough to know if we require or forbid a body in this case.
605 if Operating_Mode = Check_Syntax then
609 -- Check for body not allowed
611 if (Main_Kind = N_Package_Declaration
612 and then not Body_Required (Main_Unit_Node))
613 or else (Main_Kind = N_Generic_Package_Declaration
614 and then not Body_Required (Main_Unit_Node))
615 or else Main_Kind = N_Package_Renaming_Declaration
616 or else Main_Kind = N_Subprogram_Renaming_Declaration
617 or else Nkind (Original_Node (Unit (Main_Unit_Node)))
618 in N_Generic_Instantiation
620 Sname := Unit_Name (Main_Unit);
622 -- If we do not already have a body name, then get the body name
623 -- (but how can we have a body name here???)
625 if not Is_Body_Name (Sname) then
626 Sname := Get_Body_Name (Sname);
629 Fname := Get_File_Name (Sname, Subunit => False);
630 Src_Ind := Load_Source_File (Fname);
632 -- Case where body is present and it is not a subunit. Exclude the
633 -- subunit case, because it has nothing to do with the package we are
634 -- compiling. It is illegal for a child unit and a subunit with the
635 -- same expanded name (RM 10.2(9)) to appear together in a partition,
636 -- but there is nothing to stop a compilation environment from having
637 -- both, and the test here simply allows that. If there is an attempt
638 -- to include both in a partition, this is diagnosed at bind time. In
639 -- Ada 83 mode this is not a warning case.
641 -- Note: if weird file names are being used, we can have a situation
642 -- where the file name that supposedly contains body in fact contains
643 -- a spec, or we can't tell what it contains. Skip the error message
646 -- Also ignore body that is nothing but pragma No_Body; (that's the
647 -- whole point of this pragma, to be used this way and to cause the
648 -- body file to be ignored in this context).
650 if Src_Ind /= No_Source_File
651 and then Get_Expected_Unit_Type (Fname) = Expect_Body
652 and then not Source_File_Is_Subunit (Src_Ind)
653 and then not Source_File_Is_No_Body (Src_Ind)
655 Errout.Finalize (Last_Call => False);
657 Error_Msg_Unit_1 := Sname;
659 -- Ada 83 case of a package body being ignored. This is not an
660 -- error as far as the Ada 83 RM is concerned, but it is almost
661 -- certainly not what is wanted so output a warning. Give this
662 -- message only if there were no errors, since otherwise it may
663 -- be incorrect (we may have misinterpreted a junk spec as not
664 -- needing a body when it really does).
666 if Main_Kind = N_Package_Declaration
667 and then Ada_Version = Ada_83
668 and then Operating_Mode = Generate_Code
669 and then Distribution_Stub_Mode /= Generate_Caller_Stub_Body
670 and then not Compilation_Errors
673 ("package $$ does not require a body?", Main_Unit_Node);
674 Error_Msg_File_1 := Fname;
675 Error_Msg_N ("body in file{? will be ignored", Main_Unit_Node);
677 -- Ada 95 cases of a body file present when no body is
678 -- permitted. This we consider to be an error.
681 -- For generic instantiations, we never allow a body
683 if Nkind (Original_Node (Unit (Main_Unit_Node)))
684 in N_Generic_Instantiation
687 ("generic instantiation for $$ does not allow a body");
689 -- A library unit that is a renaming never allows a body
691 elsif Main_Kind in N_Renaming_Declaration then
693 ("renaming declaration for $$ does not allow a body!");
695 -- Remaining cases are packages and generic packages. Here
696 -- we only do the test if there are no previous errors,
697 -- because if there are errors, they may lead us to
698 -- incorrectly believe that a package does not allow a body
699 -- when in fact it does.
701 elsif not Compilation_Errors then
702 if Main_Kind = N_Package_Declaration then
704 ("package $$ does not allow a body!");
706 elsif Main_Kind = N_Generic_Package_Declaration then
708 ("generic package $$ does not allow a body!");
721 procedure Check_Rep_Info is
723 if List_Representation_Info /= 0
724 or else List_Representation_Info_Mechanisms
729 ("cannot generate representation information, no code generated");
736 -- Start of processing for Gnat1drv
739 -- This inner block is set up to catch assertion errors and constraint
740 -- errors. Since the code for handling these errors can cause another
741 -- exception to be raised (namely Unrecoverable_Error), we need two
742 -- nested blocks, so that the outer one handles unrecoverable error.
745 -- Initialize all packages. For the most part, these initialization
746 -- calls can be made in any order. Exceptions are as follows:
748 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
749 -- because it initializes a table filled by Scan_Compiler_Arguments.
755 Scan_Compiler_Arguments;
756 Osint.Add_Default_Search_Dirs;
776 Sem_Type.Init_Interp_Tables;
778 -- Acquire target parameters from system.ads (source of package System)
783 S : Source_File_Index;
787 Name_Buffer (1 .. 10) := "system.ads";
790 S := Load_Source_File (N);
792 if S = No_Source_File then
794 ("fatal error, run-time library not installed correctly");
795 Write_Line ("cannot locate file system.ads");
796 raise Unrecoverable_Error;
798 -- Remember source index of system.ads (which was read successfully)
801 System_Source_File_Index := S;
804 Targparm.Get_Target_Parameters
805 (System_Text => Source_Text (S),
806 Source_First => Source_First (S),
807 Source_Last => Source_Last (S));
809 -- Acquire configuration pragma information from Targparm
811 Restrict.Restrictions := Targparm.Restrictions_On_Target;
814 Adjust_Global_Switches;
816 -- Output copyright notice if full list mode unless we have a list
817 -- file, in which case we defer this so that it is output in the file
819 if (Verbose_Mode or else (Full_List and then Full_List_File_Name = null))
820 and then not Debug_Flag_7
824 Write_Str (Gnat_Version_String);
826 Write_Str ("Copyright 1992-" & Current_Year
827 & ", Free Software Foundation, Inc.");
831 -- Check we do not have more than one source file, this happens only in
832 -- the case where the driver is called directly, it cannot happen when
833 -- gnat1 is invoked from gcc in the normal case.
835 if Osint.Number_Of_Files /= 1 then
838 Osint.Fail ("you must provide one source file");
840 elsif Usage_Requested then
844 Original_Operating_Mode := Operating_Mode;
847 -- Exit with errors if the main source could not be parsed. Also, when
848 -- -gnatd.H is present, the source file is not set.
850 if Sinput.Main_Source_File = No_Source_File then
852 -- Handle -gnatd.H debug mode
854 if Debug_Flag_Dot_HH then
856 -- For -gnatd.H, lock all the tables to keep the convention that
857 -- the backend needs to unlock the tables it wants to touch.
870 -- And all we need to do is to call the back end
872 Back_End.Call_Back_End (Back_End.Generate_Object);
875 Errout.Finalize (Last_Call => True);
876 Errout.Output_Messages;
877 Exit_Program (E_Errors);
880 Main_Unit_Node := Cunit (Main_Unit);
881 Main_Kind := Nkind (Unit (Main_Unit_Node));
884 -- In CodePeer mode we always delete old SCIL files before regenerating
885 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
886 -- files generated by CodePeer itself.
888 if CodePeer_Mode then
889 Comperr.Delete_SCIL_Files;
892 -- Exit if compilation errors detected
894 Errout.Finalize (Last_Call => False);
896 if Compilation_Errors then
898 Sem_Ch13.Validate_Unchecked_Conversions;
899 Sem_Ch13.Validate_Address_Clauses;
900 Sem_Ch13.Validate_Independence;
901 Errout.Output_Messages;
904 -- Generate ALI file if specially requested
906 if Opt.Force_ALI_Tree_File then
907 Write_ALI (Object => False);
911 Errout.Finalize (Last_Call => True);
912 Exit_Program (E_Errors);
915 -- Set Generate_Code on main unit and its spec. We do this even if are
916 -- not generating code, since Lib-Writ uses this to determine which
917 -- units get written in the ali file.
919 Set_Generate_Code (Main_Unit);
921 -- If we have a corresponding spec, and it comes from source or it is
922 -- not a generated spec for a child subprogram body, then we need object
923 -- code for the spec unit as well.
925 if Nkind (Unit (Main_Unit_Node)) in N_Unit_Body
926 and then not Acts_As_Spec (Main_Unit_Node)
928 if Nkind (Unit (Main_Unit_Node)) = N_Subprogram_Body
929 and then not Comes_From_Source (Library_Unit (Main_Unit_Node))
934 (Get_Cunit_Unit_Number (Library_Unit (Main_Unit_Node)));
938 -- Case of no code required to be generated, exit indicating no error
940 if Original_Operating_Mode = Check_Syntax then
942 Errout.Finalize (Last_Call => True);
943 Errout.Output_Messages;
948 -- Use a goto instead of calling Exit_Program so that finalization
953 elsif Original_Operating_Mode = Check_Semantics then
954 Back_End_Mode := Declarations_Only;
956 -- All remaining cases are cases in which the user requested that code
957 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
958 -- can in fact satisfy this request.
960 -- Cannot generate code if someone has turned off code generation for
961 -- any reason at all. We will try to figure out a reason below.
963 elsif Operating_Mode /= Generate_Code then
964 Back_End_Mode := Skip;
966 -- We can generate code for a subprogram body unless there were missing
967 -- subunits. Note that we always generate code for all generic units (a
968 -- change from some previous versions of GNAT).
970 elsif Main_Kind = N_Subprogram_Body and then not Subunits_Missing then
971 Back_End_Mode := Generate_Object;
973 -- We can generate code for a package body unless there are subunits
974 -- missing (note that we always generate code for generic units, which
975 -- is a change from some earlier versions of GNAT).
977 elsif Main_Kind = N_Package_Body and then not Subunits_Missing then
978 Back_End_Mode := Generate_Object;
980 -- We can generate code for a package declaration or a subprogram
981 -- declaration only if it does not required a body.
983 elsif Nkind_In (Main_Kind,
984 N_Package_Declaration,
985 N_Subprogram_Declaration)
987 (not Body_Required (Main_Unit_Node)
989 Distribution_Stub_Mode = Generate_Caller_Stub_Body)
991 Back_End_Mode := Generate_Object;
993 -- We can generate code for a generic package declaration of a generic
994 -- subprogram declaration only if does not require a body.
996 elsif Nkind_In (Main_Kind, N_Generic_Package_Declaration,
997 N_Generic_Subprogram_Declaration)
998 and then not Body_Required (Main_Unit_Node)
1000 Back_End_Mode := Generate_Object;
1002 -- Compilation units that are renamings do not require bodies, so we can
1003 -- generate code for them.
1005 elsif Nkind_In (Main_Kind, N_Package_Renaming_Declaration,
1006 N_Subprogram_Renaming_Declaration)
1008 Back_End_Mode := Generate_Object;
1010 -- Compilation units that are generic renamings do not require bodies
1011 -- so we can generate code for them.
1013 elsif Main_Kind in N_Generic_Renaming_Declaration then
1014 Back_End_Mode := Generate_Object;
1016 -- It's not an error to generate SCIL for e.g. a spec which has a body
1018 elsif CodePeer_Mode then
1019 Back_End_Mode := Generate_Object;
1021 -- In all other cases (specs which have bodies, generics, and bodies
1022 -- where subunits are missing), we cannot generate code and we generate
1023 -- a warning message. Note that generic instantiations are gone at this
1024 -- stage since they have been replaced by their instances.
1027 Back_End_Mode := Skip;
1030 -- At this stage Back_End_Mode is set to indicate if the backend should
1031 -- be called to generate code. If it is Skip, then code generation has
1032 -- been turned off, even though code was requested by the original
1033 -- command. This is not an error from the user point of view, but it is
1034 -- an error from the point of view of the gcc driver, so we must exit
1035 -- with an error status.
1037 -- We generate an informative message (from the gcc point of view, it
1038 -- is an error message, but from the users point of view this is not an
1039 -- error, just a consequence of compiling something that cannot
1042 if Back_End_Mode = Skip then
1044 Write_Str ("cannot generate code for ");
1045 Write_Str ("file ");
1046 Write_Name (Unit_File_Name (Main_Unit));
1048 if Subunits_Missing then
1049 Write_Str (" (missing subunits)");
1052 -- Force generation of ALI file, for backward compatibility
1054 Opt.Force_ALI_Tree_File := True;
1056 elsif Main_Kind = N_Subunit then
1057 Write_Str (" (subunit)");
1060 -- Force generation of ALI file, for backward compatibility
1062 Opt.Force_ALI_Tree_File := True;
1064 elsif Main_Kind = N_Subprogram_Declaration then
1065 Write_Str (" (subprogram spec)");
1068 -- Generic package body in GNAT implementation mode
1070 elsif Main_Kind = N_Package_Body and then GNAT_Mode then
1071 Write_Str (" (predefined generic)");
1074 -- Force generation of ALI file, for backward compatibility
1076 Opt.Force_ALI_Tree_File := True;
1078 -- Only other case is a package spec
1081 Write_Str (" (package spec)");
1085 Set_Standard_Output;
1087 Sem_Ch13.Validate_Unchecked_Conversions;
1088 Sem_Ch13.Validate_Address_Clauses;
1089 Sem_Ch13.Validate_Independence;
1090 Errout.Finalize (Last_Call => True);
1091 Errout.Output_Messages;
1095 -- Generate ALI file if specially requested, or for missing subunits,
1096 -- subunits or predefined generic.
1098 if Opt.Force_ALI_Tree_File then
1099 Write_ALI (Object => False);
1105 -- Exit program with error indication, to kill object file
1107 Exit_Program (E_No_Code);
1110 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1111 -- as indicated by Back_Annotate_Rep_Info being set to True.
1113 -- We don't call for annotations on a subunit, because to process those
1114 -- the back-end requires that the parent(s) be properly compiled.
1116 -- Annotation is suppressed for targets where front-end layout is
1117 -- enabled, because the front end determines representations.
1119 -- Annotation is also suppressed in the case of compiling for a VM,
1120 -- since representations are largely symbolic there.
1122 if Back_End_Mode = Declarations_Only
1123 and then (not (Back_Annotate_Rep_Info or Generate_SCIL)
1124 or else Main_Kind = N_Subunit
1125 or else Targparm.Frontend_Layout_On_Target
1126 or else Targparm.VM_Target /= No_VM)
1128 Sem_Ch13.Validate_Unchecked_Conversions;
1129 Sem_Ch13.Validate_Address_Clauses;
1130 Sem_Ch13.Validate_Independence;
1131 Errout.Finalize (Last_Call => True);
1132 Errout.Output_Messages;
1133 Write_ALI (Object => False);
1141 -- Ensure that we properly register a dependency on system.ads, since
1142 -- even if we do not semantically depend on this, Targparm has read
1143 -- system parameters from the system.ads file.
1145 Lib.Writ.Ensure_System_Dependency;
1147 -- Add dependencies, if any, on preprocessing data file and on
1148 -- preprocessing definition file(s).
1150 Prepcomp.Add_Dependencies;
1152 -- Back end needs to explicitly unlock tables it needs to touch
1165 -- Here we call the back end to generate the output code
1167 Generating_Code := True;
1168 Back_End.Call_Back_End (Back_End_Mode);
1170 -- Once the backend is complete, we unlock the names table. This call
1171 -- allows a few extra entries, needed for example for the file name for
1172 -- the library file output.
1176 -- Generate the call-graph output of dispatching calls
1178 Exp_CG.Generate_CG_Output;
1180 -- Validate unchecked conversions (using the values for size and
1181 -- alignment annotated by the backend where possible).
1183 Sem_Ch13.Validate_Unchecked_Conversions;
1185 -- Validate address clauses (again using alignment values annotated
1186 -- by the backend where possible).
1188 Sem_Ch13.Validate_Address_Clauses;
1190 -- Validate independence pragmas (again using values annotated by
1191 -- the back end for component layout etc.)
1193 Sem_Ch13.Validate_Independence;
1195 -- Now we complete output of errors, rep info and the tree info. These
1196 -- are delayed till now, since it is perfectly possible for gigi to
1197 -- generate errors, modify the tree (in particular by setting flags
1198 -- indicating that elaboration is required, and also to back annotate
1199 -- representation information for List_Rep_Info.
1201 Errout.Finalize (Last_Call => True);
1202 Errout.Output_Messages;
1206 -- Only write the library if the backend did not generate any error
1207 -- messages. Otherwise signal errors to the driver program so that
1208 -- there will be no attempt to generate an object file.
1210 if Compilation_Errors then
1212 Exit_Program (E_Errors);
1215 Write_ALI (Object => (Back_End_Mode = Generate_Object));
1217 if not Compilation_Errors then
1219 -- In case of ada backends, we need to make sure that the generated
1220 -- object file has a timestamp greater than the ALI file. We do this
1221 -- to make gnatmake happy when checking the ALI and obj timestamps,
1222 -- where it expects the object file being written after the ali file.
1224 -- Gnatmake's assumption is true for gcc platforms where the gcc
1225 -- wrapper needs to call the assembler after calling gnat1, but is
1226 -- not true for ada backends, where the object files are created
1227 -- directly by gnat1 (so are created before the ali file).
1229 Back_End.Gen_Or_Update_Object_File;
1232 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1233 -- Write_ALI may in fact result in further tree decoration from the
1234 -- original tree file. Note that we dump the tree just before generating
1235 -- it, so that the dump will exactly reflect what is written out.
1240 -- Finalize name table and we are all done
1245 -- Handle fatal internal compiler errors
1247 when Rtsfind.RE_Not_Available =>
1248 Comperr.Compiler_Abort ("RE_Not_Available");
1250 when System.Assertions.Assert_Failure =>
1251 Comperr.Compiler_Abort ("Assert_Failure");
1253 when Constraint_Error =>
1254 Comperr.Compiler_Abort ("Constraint_Error");
1256 when Program_Error =>
1257 Comperr.Compiler_Abort ("Program_Error");
1259 when Storage_Error =>
1261 -- Assume this is a bug. If it is real, the message will in any case
1262 -- say Storage_Error, giving a strong hint!
1264 Comperr.Compiler_Abort ("Storage_Error");
1270 -- The outer exception handles an unrecoverable error
1273 when Unrecoverable_Error =>
1274 Errout.Finalize (Last_Call => True);
1275 Errout.Output_Messages;
1278 Write_Str ("compilation abandoned");
1281 Set_Standard_Output;
1284 Exit_Program (E_Errors);