1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2013, 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;
65 with Sinfo; use Sinfo;
66 with Sinput.L; use Sinput.L;
68 with Sprint; use Sprint;
70 with Stylesw; use Stylesw;
71 with Targparm; use Targparm;
73 with Treepr; use Treepr;
75 with Types; use Types;
76 with Uintp; use Uintp;
77 with Uname; use Uname;
80 with Validsw; use Validsw;
82 with System.Assertions;
85 Main_Unit_Node : Node_Id;
86 -- Compilation unit node for main unit
88 Main_Kind : Node_Kind;
89 -- Kind of main compilation unit node
91 Back_End_Mode : Back_End.Back_End_Mode_Type;
92 -- Record back end mode
94 procedure Adjust_Global_Switches;
95 -- There are various interactions between front end switch settings,
96 -- including debug switch settings and target dependent parameters.
97 -- This procedure takes care of properly handling these interactions.
98 -- We do it after scanning out all the switches, so that we are not
99 -- depending on the order in which switches appear.
101 procedure Check_Bad_Body;
102 -- Called to check if the unit we are compiling has a bad body
104 procedure Check_Rep_Info;
105 -- Called when we are not generating code, to check if -gnatR was requested
106 -- and if so, explain that we will not be honoring the request.
108 ----------------------------
109 -- Adjust_Global_Switches --
110 ----------------------------
112 procedure Adjust_Global_Switches is
114 -- -gnatd.M enables Relaxed_RM_Semantics
116 if Debug_Flag_Dot_MM then
117 Relaxed_RM_Semantics := True;
120 -- -gnatd.V or -gnatd.u enables special C expansion mode
122 if Debug_Flag_Dot_VV or Debug_Flag_Dot_U then
123 Modify_Tree_For_C := True;
126 -- -gnatd.E sets Error_To_Warning mode, causing selected error messages
127 -- to be treated as warnings instead of errors.
129 if Debug_Flag_Dot_EE then
130 Error_To_Warning := True;
133 -- Disable CodePeer_Mode in Check_Syntax, since we need front-end
136 if Operating_Mode = Check_Syntax then
137 CodePeer_Mode := False;
140 -- Set ASIS mode if -gnatt and -gnatc are set
142 if Operating_Mode = Check_Semantics and then Tree_Output then
145 -- Turn off inlining in ASIS mode, since ASIS cannot handle the extra
146 -- information in the trees caused by inlining being active.
148 -- More specifically, the tree seems to be malformed from the ASIS
149 -- point of view if -gnatc and -gnatn appear together???
151 Inline_Active := False;
153 -- Turn off SCIL generation and CodePeer mode in semantics mode,
154 -- since SCIL requires front-end expansion.
156 Generate_SCIL := False;
157 CodePeer_Mode := False;
160 -- SCIL mode needs to disable front-end inlining since the generated
161 -- trees (in particular order and consistency between specs compiled
162 -- as part of a main unit or as part of a with-clause) are causing
165 if Generate_SCIL then
166 Front_End_Inlining := False;
169 -- Tune settings for optimal SCIL generation in CodePeer mode
171 if CodePeer_Mode then
173 -- Turn off inlining, confuses CodePeer output and gains nothing
175 Front_End_Inlining := False;
176 Inline_Active := False;
178 -- Disable front-end optimizations, to keep the tree as close to the
179 -- source code as possible, and also to avoid inconsistencies between
180 -- trees when using different optimization switches.
182 Optimization_Level := 0;
184 -- Enable some restrictions systematically to simplify the generated
185 -- code (and ease analysis). Note that restriction checks are also
186 -- disabled in CodePeer mode, see Restrict.Check_Restriction, and
187 -- user specified Restrictions pragmas are ignored, see
188 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
190 Restrict.Restrictions.Set (No_Initialize_Scalars) := True;
191 Restrict.Restrictions.Set (No_Task_Hierarchy) := True;
192 Restrict.Restrictions.Set (No_Abort_Statements) := True;
193 Restrict.Restrictions.Set (Max_Asynchronous_Select_Nesting) := True;
194 Restrict.Restrictions.Value (Max_Asynchronous_Select_Nesting) := 0;
196 -- Suppress division by zero and access checks since they are handled
197 -- implicitly by CodePeer.
199 -- Turn off dynamic elaboration checks: generates inconsistencies in
200 -- trees between specs compiled as part of a main unit or as part of
203 -- Turn off alignment checks: these cannot be proved statically by
204 -- CodePeer and generate false positives.
206 -- Enable all other language checks
208 Suppress_Options.Suppress :=
209 (Access_Check => True,
210 Alignment_Check => True,
211 Division_Check => True,
212 Elaboration_Check => True,
215 Dynamic_Elaboration_Checks := False;
217 -- Set STRICT mode for overflow checks if not set explicitly. This
218 -- prevents suppressing of overflow checks by default, in code down
221 if Suppress_Options.Overflow_Mode_General = Not_Set then
222 Suppress_Options.Overflow_Mode_General := Strict;
223 Suppress_Options.Overflow_Mode_Assertions := Strict;
226 -- CodePeer handles division and overflow checks directly, based on
227 -- the marks set by the frontend, hence no special expansion should
228 -- be performed in the frontend for division and overflow checks.
230 Backend_Divide_Checks_On_Target := True;
231 Backend_Overflow_Checks_On_Target := True;
233 -- Kill debug of generated code, since it messes up sloc values
235 Debug_Generated_Code := False;
237 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
238 -- Do we really need to spend time generating xref in CodePeer
239 -- mode??? Consider setting Xref_Active to False.
243 -- Polling mode forced off, since it generates confusing junk
245 Polling_Required := False;
247 -- Set operating mode to Generate_Code to benefit from full front-end
248 -- expansion (e.g. generics).
250 Operating_Mode := Generate_Code;
252 -- We need SCIL generation of course
254 Generate_SCIL := True;
256 -- Enable assertions, since they give CodePeer valuable extra info
258 Assertions_Enabled := True;
260 -- Disable all simple value propagation. This is an optimization
261 -- which is valuable for code optimization, and also for generation
262 -- of compiler warnings, but these are being turned off by default,
263 -- and CodePeer generates better messages (referencing original
264 -- variables) this way.
266 Debug_Flag_MM := True;
268 -- Set normal RM validity checking, and checking of IN OUT parameters
269 -- (this might give CodePeer more useful checks to analyze, to be
270 -- confirmed???). All other validity checking is turned off, since
271 -- this can generate very complex trees that only confuse CodePeer
272 -- and do not bring enough useful info.
274 Reset_Validity_Check_Options;
275 Validity_Check_Default := True;
276 Validity_Check_In_Out_Params := True;
277 Validity_Check_In_Params := True;
279 -- Turn off style check options since we are not interested in any
280 -- front-end warnings when we are getting CodePeer output.
282 Reset_Style_Check_Options;
284 -- Always perform semantics and generate ali files in CodePeer mode,
285 -- so that a gnatmake -c -k will proceed further when possible.
287 Force_ALI_Tree_File := True;
288 Try_Semantics := True;
290 -- Make the Ada front-end more liberal so that the compiler will
291 -- allow illegal code that is allowed by other compilers. CodePeer
292 -- is in the business of finding problems, not enforcing rules.
293 -- This is useful when using CodePeer mode with other compilers.
295 Relaxed_RM_Semantics := True;
298 -- Enable some individual switches that are implied by relaxed RM
301 if Relaxed_RM_Semantics then
302 Opt.Allow_Integer_Address := True;
303 Overriding_Renamings := True;
304 Treat_Categorization_Errors_As_Warnings := True;
307 -- Enable GNATprove_Mode when using -gnatd.F switch
309 if Debug_Flag_Dot_FF then
310 GNATprove_Mode := True;
313 -- GNATprove_Mode is also activated by default in the gnat2why
316 if GNATprove_Mode then
318 -- Turn off inlining, which would confuse formal verification output
321 Front_End_Inlining := False;
322 Inline_Active := False;
324 -- Disable front-end optimizations, to keep the tree as close to the
325 -- source code as possible, and also to avoid inconsistencies between
326 -- trees when using different optimization switches.
328 Optimization_Level := 0;
330 -- Enable some restrictions systematically to simplify the generated
331 -- code (and ease analysis). Note that restriction checks are also
332 -- disabled in SPARK mode, see Restrict.Check_Restriction, and user
333 -- specified Restrictions pragmas are ignored, see
334 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
336 Restrict.Restrictions.Set (No_Initialize_Scalars) := True;
338 -- Note: at this point we used to suppress various checks, but that
339 -- is not what we want. We need the semantic processing for these
340 -- checks (which will set flags like Do_Overflow_Check, showing the
341 -- points at which potential checks are required semantically). We
342 -- don't want the expansion associated with these checks, but that
343 -- happens anyway because this expansion is simply not done in the
344 -- SPARK version of the expander.
346 -- Turn off dynamic elaboration checks: generates inconsistencies in
347 -- trees between specs compiled as part of a main unit or as part of
350 -- Comment is incomplete, SPARK semantics rely on static mode no???
352 Dynamic_Elaboration_Checks := False;
354 -- Set STRICT mode for overflow checks if not set explicitly. This
355 -- prevents suppressing of overflow checks by default, in code down
358 if Suppress_Options.Overflow_Mode_General = Not_Set then
359 Suppress_Options.Overflow_Mode_General := Strict;
360 Suppress_Options.Overflow_Mode_Assertions := Strict;
363 -- Kill debug of generated code, since it messes up sloc values
365 Debug_Generated_Code := False;
367 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
368 -- as it is needed for computing effects of subprograms in the formal
369 -- verification backend.
373 -- Polling mode forced off, since it generates confusing junk
375 Polling_Required := False;
377 -- Set operating mode to Check_Semantics, but a light front-end
378 -- expansion is still performed.
380 Operating_Mode := Check_Semantics;
382 -- Enable assertions, since they give valuable extra information for
383 -- formal verification.
385 Assertions_Enabled := True;
387 -- Turn off style check options since we are not interested in any
388 -- front-end warnings when we are getting SPARK output.
390 Reset_Style_Check_Options;
392 -- Suppress the generation of name tables for enumerations, which are
393 -- not needed for formal verification, and fall outside the SPARK
394 -- subset (use of pointers).
396 Global_Discard_Names := True;
398 -- Suppress the expansion of tagged types and dispatching calls,
399 -- which lead to the generation of non-SPARK code (use of pointers),
400 -- which is more complex to formally verify than the original source.
402 Tagged_Type_Expansion := False;
405 -- Set Configurable_Run_Time mode if system.ads flag set or if the
406 -- special debug flag -gnatdY is set.
408 if Targparm.Configurable_Run_Time_On_Target or Debug_Flag_YY then
409 Configurable_Run_Time_Mode := True;
412 -- Set -gnatR3m mode if debug flag A set
414 if Debug_Flag_AA then
415 Back_Annotate_Rep_Info := True;
416 List_Representation_Info := 1;
417 List_Representation_Info_Mechanisms := True;
420 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
422 if Debug_Flag_Dot_A then
423 Ttypes.Target_Strict_Alignment := True;
426 -- Increase size of allocated entities if debug flag -gnatd.N is set
428 if Debug_Flag_Dot_NN then
429 Atree.Num_Extension_Nodes := Atree.Num_Extension_Nodes + 1;
432 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
433 -- is enabled. The front end's layout phase currently treats types that
434 -- have discriminant-dependent arrays as not being static even when a
435 -- discriminant constraint on the type is static, and this leads to
436 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
438 if Debug_Flag_Dot_T or else Frontend_Layout_On_Target then
439 Static_Dispatch_Tables := False;
442 -- Flip endian mode if -gnatd8 set
445 Ttypes.Bytes_Big_Endian := not Ttypes.Bytes_Big_Endian;
448 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
449 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
450 -- before doing this, so we know if we are in real OpenVMS or not.
452 Opt.True_VMS_Target := Targparm.OpenVMS_On_Target;
455 Targparm.OpenVMS_On_Target := True;
456 Hostparm.OpenVMS := True;
459 -- Activate front end layout if debug flag -gnatdF is set
461 if Debug_Flag_FF then
462 Targparm.Frontend_Layout_On_Target := True;
465 -- Set and check exception mechanism
467 if Targparm.ZCX_By_Default_On_Target then
468 Exception_Mechanism := Back_End_Exceptions;
471 -- Set proper status for overflow check mechanism
473 -- If already set (by -gnato or above in SPARK or CodePeer mode) then we
474 -- have nothing to do.
476 if Opt.Suppress_Options.Overflow_Mode_General /= Not_Set then
479 -- Otherwise set overflow mode defaults
482 -- Otherwise set overflow checks off by default
484 Suppress_Options.Suppress (Overflow_Check) := True;
486 -- Set appropriate default overflow handling mode. Note: at present
487 -- we set STRICT in all three of the following cases. They are
488 -- separated because in the future we may make different choices.
490 -- By default set STRICT mode if -gnatg in effect
493 Suppress_Options.Overflow_Mode_General := Strict;
494 Suppress_Options.Overflow_Mode_Assertions := Strict;
496 -- If we have backend divide and overflow checks, then by default
497 -- overflow checks are STRICT. Historically this code used to also
498 -- activate overflow checks, although no target currently has these
499 -- flags set, so this was dead code anyway.
501 elsif Targparm.Backend_Divide_Checks_On_Target
503 Targparm.Backend_Overflow_Checks_On_Target
505 Suppress_Options.Overflow_Mode_General := Strict;
506 Suppress_Options.Overflow_Mode_Assertions := Strict;
508 -- Otherwise for now, default is STRICT mode. This may change in the
509 -- future, but for now this is the compatible behavior with previous
513 Suppress_Options.Overflow_Mode_General := Strict;
514 Suppress_Options.Overflow_Mode_Assertions := Strict;
518 -- Set default for atomic synchronization. As this synchronization
519 -- between atomic accesses can be expensive, and not typically needed
520 -- on some targets, an optional target parameter can turn the option
521 -- off. Note Atomic Synchronization is implemented as check.
523 Suppress_Options.Suppress (Atomic_Synchronization) :=
524 not Atomic_Sync_Default_On_Target;
526 -- Set switch indicating if back end can handle limited types, and
527 -- guarantee that no incorrect copies are made (e.g. in the context
528 -- of an if or case expression).
530 -- Debug flag -gnatd.L decisively sets usage on
532 if Debug_Flag_Dot_LL then
533 Back_End_Handles_Limited_Types := True;
535 -- If no debug flag, usage off for AAMP, VM, SCIL cases
538 or else VM_Target /= No_VM
539 or else Generate_SCIL
541 Back_End_Handles_Limited_Types := False;
543 -- Otherwise normal gcc back end, for now still turn flag off by
544 -- default, since there are unresolved problems in the front end.
547 Back_End_Handles_Limited_Types := False;
550 -- If the inlining level has not been set by the user, compute it from
551 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
553 if Inline_Level = 0 then
554 if Optimization_Level < 3 then
561 -- Output warning if -gnateE specified and cannot be supported
563 if Exception_Extra_Info
564 and then Restrict.No_Exception_Handlers_Set
568 ("warning: extra exception information (-gnateE) was specified");
571 ("warning: this capability is not available in this configuration");
576 -- Finally capture adjusted value of Suppress_Options as the initial
577 -- value for Scope_Suppress, which will be modified as we move from
578 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
580 Sem.Scope_Suppress := Opt.Suppress_Options;
581 end Adjust_Global_Switches;
587 procedure Check_Bad_Body is
588 Sname : Unit_Name_Type;
589 Src_Ind : Source_File_Index;
590 Fname : File_Name_Type;
592 procedure Bad_Body_Error (Msg : String);
593 -- Issue message for bad body found
599 procedure Bad_Body_Error (Msg : String) is
601 Error_Msg_N (Msg, Main_Unit_Node);
602 Error_Msg_File_1 := Fname;
603 Error_Msg_N ("remove incorrect body in file{!", Main_Unit_Node);
606 -- Start of processing for Check_Bad_Body
609 -- Nothing to do if we are only checking syntax, because we don't know
610 -- enough to know if we require or forbid a body in this case.
612 if Operating_Mode = Check_Syntax then
616 -- Check for body not allowed
618 if (Main_Kind = N_Package_Declaration
619 and then not Body_Required (Main_Unit_Node))
620 or else (Main_Kind = N_Generic_Package_Declaration
621 and then not Body_Required (Main_Unit_Node))
622 or else Main_Kind = N_Package_Renaming_Declaration
623 or else Main_Kind = N_Subprogram_Renaming_Declaration
624 or else Nkind (Original_Node (Unit (Main_Unit_Node)))
625 in N_Generic_Instantiation
627 Sname := Unit_Name (Main_Unit);
629 -- If we do not already have a body name, then get the body name
630 -- (but how can we have a body name here???)
632 if not Is_Body_Name (Sname) then
633 Sname := Get_Body_Name (Sname);
636 Fname := Get_File_Name (Sname, Subunit => False);
637 Src_Ind := Load_Source_File (Fname);
639 -- Case where body is present and it is not a subunit. Exclude the
640 -- subunit case, because it has nothing to do with the package we are
641 -- compiling. It is illegal for a child unit and a subunit with the
642 -- same expanded name (RM 10.2(9)) to appear together in a partition,
643 -- but there is nothing to stop a compilation environment from having
644 -- both, and the test here simply allows that. If there is an attempt
645 -- to include both in a partition, this is diagnosed at bind time. In
646 -- Ada 83 mode this is not a warning case.
648 -- Note: if weird file names are being used, we can have a situation
649 -- where the file name that supposedly contains body in fact contains
650 -- a spec, or we can't tell what it contains. Skip the error message
653 -- Also ignore body that is nothing but pragma No_Body; (that's the
654 -- whole point of this pragma, to be used this way and to cause the
655 -- body file to be ignored in this context).
657 if Src_Ind /= No_Source_File
658 and then Get_Expected_Unit_Type (Fname) = Expect_Body
659 and then not Source_File_Is_Subunit (Src_Ind)
660 and then not Source_File_Is_No_Body (Src_Ind)
662 Errout.Finalize (Last_Call => False);
664 Error_Msg_Unit_1 := Sname;
666 -- Ada 83 case of a package body being ignored. This is not an
667 -- error as far as the Ada 83 RM is concerned, but it is almost
668 -- certainly not what is wanted so output a warning. Give this
669 -- message only if there were no errors, since otherwise it may
670 -- be incorrect (we may have misinterpreted a junk spec as not
671 -- needing a body when it really does).
673 if Main_Kind = N_Package_Declaration
674 and then Ada_Version = Ada_83
675 and then Operating_Mode = Generate_Code
676 and then Distribution_Stub_Mode /= Generate_Caller_Stub_Body
677 and then not Compilation_Errors
680 ("package $$ does not require a body??", Main_Unit_Node);
681 Error_Msg_File_1 := Fname;
682 Error_Msg_N ("body in file{ will be ignored??", Main_Unit_Node);
684 -- Ada 95 cases of a body file present when no body is
685 -- permitted. This we consider to be an error.
688 -- For generic instantiations, we never allow a body
690 if Nkind (Original_Node (Unit (Main_Unit_Node)))
691 in N_Generic_Instantiation
694 ("generic instantiation for $$ does not allow a body");
696 -- A library unit that is a renaming never allows a body
698 elsif Main_Kind in N_Renaming_Declaration then
700 ("renaming declaration for $$ does not allow a body!");
702 -- Remaining cases are packages and generic packages. Here
703 -- we only do the test if there are no previous errors,
704 -- because if there are errors, they may lead us to
705 -- incorrectly believe that a package does not allow a
706 -- body when in fact it does.
708 elsif not Compilation_Errors then
709 if Main_Kind = N_Package_Declaration then
711 ("package $$ does not allow a body!");
713 elsif Main_Kind = N_Generic_Package_Declaration then
715 ("generic package $$ does not allow a body!");
728 procedure Check_Rep_Info is
730 if List_Representation_Info /= 0
731 or else List_Representation_Info_Mechanisms
736 ("cannot generate representation information, no code generated");
743 -- Start of processing for Gnat1drv
746 -- This inner block is set up to catch assertion errors and constraint
747 -- errors. Since the code for handling these errors can cause another
748 -- exception to be raised (namely Unrecoverable_Error), we need two
749 -- nested blocks, so that the outer one handles unrecoverable error.
752 -- Initialize all packages. For the most part, these initialization
753 -- calls can be made in any order. Exceptions are as follows:
755 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
756 -- because it initializes a table filled by Scan_Compiler_Arguments.
762 Scan_Compiler_Arguments;
763 Osint.Add_Default_Search_Dirs;
783 Sem_Type.Init_Interp_Tables;
785 -- Acquire target parameters from system.ads (source of package System)
790 S : Source_File_Index;
794 Name_Buffer (1 .. 10) := "system.ads";
797 S := Load_Source_File (N);
799 if S = No_Source_File then
801 ("fatal error, run-time library not installed correctly");
802 Write_Line ("cannot locate file system.ads");
803 raise Unrecoverable_Error;
805 -- Remember source index of system.ads (which was read successfully)
808 System_Source_File_Index := S;
811 Targparm.Get_Target_Parameters
812 (System_Text => Source_Text (S),
813 Source_First => Source_First (S),
814 Source_Last => Source_Last (S));
816 -- Acquire configuration pragma information from Targparm
818 Restrict.Restrictions := Targparm.Restrictions_On_Target;
821 Adjust_Global_Switches;
823 -- Output copyright notice if full list mode unless we have a list
824 -- file, in which case we defer this so that it is output in the file
826 if (Verbose_Mode or else (Full_List and then Full_List_File_Name = null))
827 and then not Debug_Flag_7
831 Write_Str (Gnat_Version_String);
833 Write_Str ("Copyright 1992-" & Current_Year
834 & ", Free Software Foundation, Inc.");
838 -- Check we do not have more than one source file, this happens only in
839 -- the case where the driver is called directly, it cannot happen when
840 -- gnat1 is invoked from gcc in the normal case.
842 if Osint.Number_Of_Files /= 1 then
845 Osint.Fail ("you must provide one source file");
847 elsif Usage_Requested then
851 -- Generate target dependent output file if requested
853 if Target_Dependent_Info_Write_Name /= null then
854 Set_Targ.Write_Target_Dependent_Values;
857 -- Call the front end
859 Original_Operating_Mode := Operating_Mode;
862 -- Exit with errors if the main source could not be parsed.
864 if Sinput.Main_Source_File = No_Source_File then
865 Errout.Finalize (Last_Call => True);
866 Errout.Output_Messages;
867 Exit_Program (E_Errors);
870 Main_Unit_Node := Cunit (Main_Unit);
871 Main_Kind := Nkind (Unit (Main_Unit_Node));
874 -- In CodePeer mode we always delete old SCIL files before regenerating
875 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
876 -- files generated by CodePeer itself.
878 if CodePeer_Mode then
879 Comperr.Delete_SCIL_Files;
882 -- Exit if compilation errors detected
884 Errout.Finalize (Last_Call => False);
886 if Compilation_Errors then
888 Sem_Ch13.Validate_Unchecked_Conversions;
889 Sem_Ch13.Validate_Address_Clauses;
890 Sem_Ch13.Validate_Independence;
891 Errout.Output_Messages;
894 -- Generate ALI file if specially requested
896 if Opt.Force_ALI_Tree_File then
897 Write_ALI (Object => False);
901 Errout.Finalize (Last_Call => True);
902 Exit_Program (E_Errors);
905 -- Set Generate_Code on main unit and its spec. We do this even if are
906 -- not generating code, since Lib-Writ uses this to determine which
907 -- units get written in the ali file.
909 Set_Generate_Code (Main_Unit);
911 -- If we have a corresponding spec, and it comes from source or it is
912 -- not a generated spec for a child subprogram body, then we need object
913 -- code for the spec unit as well.
915 if Nkind (Unit (Main_Unit_Node)) in N_Unit_Body
916 and then not Acts_As_Spec (Main_Unit_Node)
918 if Nkind (Unit (Main_Unit_Node)) = N_Subprogram_Body
919 and then not Comes_From_Source (Library_Unit (Main_Unit_Node))
924 (Get_Cunit_Unit_Number (Library_Unit (Main_Unit_Node)));
928 -- Case of no code required to be generated, exit indicating no error
930 if Original_Operating_Mode = Check_Syntax then
932 Errout.Finalize (Last_Call => True);
933 Errout.Output_Messages;
938 -- Use a goto instead of calling Exit_Program so that finalization
943 elsif Original_Operating_Mode = Check_Semantics then
944 Back_End_Mode := Declarations_Only;
946 -- All remaining cases are cases in which the user requested that code
947 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
948 -- can in fact satisfy this request.
950 -- Cannot generate code if someone has turned off code generation for
951 -- any reason at all. We will try to figure out a reason below.
953 elsif Operating_Mode /= Generate_Code then
954 Back_End_Mode := Skip;
956 -- We can generate code for a subprogram body unless there were missing
957 -- subunits. Note that we always generate code for all generic units (a
958 -- change from some previous versions of GNAT).
960 elsif Main_Kind = N_Subprogram_Body and then not Subunits_Missing then
961 Back_End_Mode := Generate_Object;
963 -- We can generate code for a package body unless there are subunits
964 -- missing (note that we always generate code for generic units, which
965 -- is a change from some earlier versions of GNAT).
967 elsif Main_Kind = N_Package_Body and then not Subunits_Missing then
968 Back_End_Mode := Generate_Object;
970 -- We can generate code for a package declaration or a subprogram
971 -- declaration only if it does not required a body.
973 elsif Nkind_In (Main_Kind,
974 N_Package_Declaration,
975 N_Subprogram_Declaration)
977 (not Body_Required (Main_Unit_Node)
979 Distribution_Stub_Mode = Generate_Caller_Stub_Body)
981 Back_End_Mode := Generate_Object;
983 -- We can generate code for a generic package declaration of a generic
984 -- subprogram declaration only if does not require a body.
986 elsif Nkind_In (Main_Kind, N_Generic_Package_Declaration,
987 N_Generic_Subprogram_Declaration)
988 and then not Body_Required (Main_Unit_Node)
990 Back_End_Mode := Generate_Object;
992 -- Compilation units that are renamings do not require bodies, so we can
993 -- generate code for them.
995 elsif Nkind_In (Main_Kind, N_Package_Renaming_Declaration,
996 N_Subprogram_Renaming_Declaration)
998 Back_End_Mode := Generate_Object;
1000 -- Compilation units that are generic renamings do not require bodies
1001 -- so we can generate code for them.
1003 elsif Main_Kind in N_Generic_Renaming_Declaration then
1004 Back_End_Mode := Generate_Object;
1006 -- It is not an error to analyze in CodePeer mode a spec which requires
1007 -- a body, in order to generate SCIL for this spec.
1009 elsif CodePeer_Mode then
1010 Back_End_Mode := Generate_Object;
1012 -- It is not an error to analyze in GNATprove mode a spec which requires
1013 -- a body, when the body is not available. During frame condition
1014 -- generation, the corresponding ALI file is generated. During
1015 -- analysis, the spec is analyzed.
1017 elsif GNATprove_Mode then
1018 Back_End_Mode := Declarations_Only;
1020 -- In all other cases (specs which have bodies, generics, and bodies
1021 -- where subunits are missing), we cannot generate code and we generate
1022 -- a warning message. Note that generic instantiations are gone at this
1023 -- stage since they have been replaced by their instances.
1026 Back_End_Mode := Skip;
1029 -- At this stage Back_End_Mode is set to indicate if the backend should
1030 -- be called to generate code. If it is Skip, then code generation has
1031 -- been turned off, even though code was requested by the original
1032 -- command. This is not an error from the user point of view, but it is
1033 -- an error from the point of view of the gcc driver, so we must exit
1034 -- with an error status.
1036 -- We generate an informative message (from the gcc point of view, it
1037 -- is an error message, but from the users point of view this is not an
1038 -- error, just a consequence of compiling something that cannot
1041 if Back_End_Mode = Skip then
1043 Write_Str ("cannot generate code for ");
1044 Write_Str ("file ");
1045 Write_Name (Unit_File_Name (Main_Unit));
1047 if Subunits_Missing then
1048 Write_Str (" (missing subunits)");
1051 -- Force generation of ALI file, for backward compatibility
1053 Opt.Force_ALI_Tree_File := True;
1055 elsif Main_Kind = N_Subunit then
1056 Write_Str (" (subunit)");
1059 -- Force generation of ALI file, for backward compatibility
1061 Opt.Force_ALI_Tree_File := True;
1063 elsif Main_Kind = N_Subprogram_Declaration then
1064 Write_Str (" (subprogram spec)");
1067 -- Generic package body in GNAT implementation mode
1069 elsif Main_Kind = N_Package_Body and then GNAT_Mode then
1070 Write_Str (" (predefined generic)");
1073 -- Force generation of ALI file, for backward compatibility
1075 Opt.Force_ALI_Tree_File := True;
1077 -- Only other case is a package spec
1080 Write_Str (" (package spec)");
1084 Set_Standard_Output;
1086 Sem_Ch13.Validate_Unchecked_Conversions;
1087 Sem_Ch13.Validate_Address_Clauses;
1088 Sem_Ch13.Validate_Independence;
1089 Errout.Finalize (Last_Call => True);
1090 Errout.Output_Messages;
1094 -- Generate ALI file if specially requested, or for missing subunits,
1095 -- subunits or predefined generic.
1097 if Opt.Force_ALI_Tree_File then
1098 Write_ALI (Object => False);
1104 -- Exit program with error indication, to kill object file
1106 Exit_Program (E_No_Code);
1109 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1110 -- as indicated by Back_Annotate_Rep_Info being set to True.
1112 -- We don't call for annotations on a subunit, because to process those
1113 -- the back-end requires that the parent(s) be properly compiled.
1115 -- Annotation is suppressed for targets where front-end layout is
1116 -- enabled, because the front end determines representations.
1118 -- Annotation is also suppressed in the case of compiling for a VM,
1119 -- since representations are largely symbolic there.
1121 if Back_End_Mode = Declarations_Only
1123 (not (Back_Annotate_Rep_Info or Generate_SCIL or GNATprove_Mode)
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;
1203 List_Rep_Info (Ttypes.Bytes_Big_Endian);
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 -- In GNATprove mode, an "object" file is always generated as the
1216 -- result of calling gnat1 or gnat2why, although this is not the
1217 -- same as the object file produced for compilation.
1219 Write_ALI (Object => (Back_End_Mode = Generate_Object
1220 or else GNATprove_Mode));
1222 if not Compilation_Errors then
1224 -- In case of ada backends, we need to make sure that the generated
1225 -- object file has a timestamp greater than the ALI file. We do this
1226 -- to make gnatmake happy when checking the ALI and obj timestamps,
1227 -- where it expects the object file being written after the ali file.
1229 -- Gnatmake's assumption is true for gcc platforms where the gcc
1230 -- wrapper needs to call the assembler after calling gnat1, but is
1231 -- not true for ada backends, where the object files are created
1232 -- directly by gnat1 (so are created before the ali file).
1234 Back_End.Gen_Or_Update_Object_File;
1237 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1238 -- Write_ALI may in fact result in further tree decoration from the
1239 -- original tree file. Note that we dump the tree just before generating
1240 -- it, so that the dump will exactly reflect what is written out.
1245 -- Finalize name table and we are all done
1250 -- Handle fatal internal compiler errors
1252 when Rtsfind.RE_Not_Available =>
1253 Comperr.Compiler_Abort ("RE_Not_Available");
1255 when System.Assertions.Assert_Failure =>
1256 Comperr.Compiler_Abort ("Assert_Failure");
1258 when Constraint_Error =>
1259 Comperr.Compiler_Abort ("Constraint_Error");
1261 when Program_Error =>
1262 Comperr.Compiler_Abort ("Program_Error");
1264 when Storage_Error =>
1266 -- Assume this is a bug. If it is real, the message will in any case
1267 -- say Storage_Error, giving a strong hint.
1269 Comperr.Compiler_Abort ("Storage_Error");
1275 -- The outer exception handles an unrecoverable error
1278 when Unrecoverable_Error =>
1279 Errout.Finalize (Last_Call => True);
1280 Errout.Output_Messages;
1283 Write_Str ("compilation abandoned");
1286 Set_Standard_Output;
1289 Exit_Program (E_Errors);