1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006 Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Back_End; use Back_End;
30 with Csets; use Csets;
31 with Debug; use Debug;
33 with Errout; use Errout;
35 with Fname; use Fname;
36 with Fname.UF; use Fname.UF;
38 with Gnatvsn; use Gnatvsn;
42 with Lib.Writ; use Lib.Writ;
44 with Namet; use Namet;
47 with Osint; use Osint;
48 with Output; use Output;
50 with Repinfo; use Repinfo;
59 with Sinfo; use Sinfo;
60 with Sinput.L; use Sinput.L;
62 with Sprint; use Sprint;
66 with Treepr; use Treepr;
68 with Types; use Types;
69 with Uintp; use Uintp;
70 with Uname; use Uname;
74 with System.Assertions;
77 Main_Unit_Node : Node_Id;
78 -- Compilation unit node for main unit
80 Main_Kind : Node_Kind;
81 -- Kind of main compilation unit node
83 Back_End_Mode : Back_End.Back_End_Mode_Type;
84 -- Record back end mode
87 -- This inner block is set up to catch assertion errors and constraint
88 -- errors. Since the code for handling these errors can cause another
89 -- exception to be raised (namely Unrecoverable_Error), we need two
90 -- nested blocks, so that the outer one handles unrecoverable error.
93 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
94 -- because it initialize a table that is filled by
95 -- Scan_Compiler_Arguments.
101 Scan_Compiler_Arguments;
102 Osint.Add_Default_Search_Dirs;
120 Sem_Type.Init_Interp_Tables;
122 -- Acquire target parameters from system.ads (source of package System)
127 S : Source_File_Index;
131 Name_Buffer (1 .. 10) := "system.ads";
134 S := Load_Source_File (N);
136 if S = No_Source_File then
138 ("fatal error, run-time library not installed correctly");
140 ("cannot locate file system.ads");
141 raise Unrecoverable_Error;
143 -- Remember source index of system.ads (which was read successfully)
146 System_Source_File_Index := S;
149 Targparm.Get_Target_Parameters
150 (System_Text => Source_Text (S),
151 Source_First => Source_First (S),
152 Source_Last => Source_Last (S));
154 -- Acquire configuration pragma information from Targparm
156 Restrict.Restrictions := Targparm.Restrictions_On_Target;
159 -- Set Configurable_Run_Time mode if system.ads flag set
161 if Targparm.Configurable_Run_Time_On_Target or Debug_Flag_YY then
162 Configurable_Run_Time_Mode := True;
165 -- Set -gnatR3m mode if debug flag A set
167 if Debug_Flag_AA then
168 Back_Annotate_Rep_Info := True;
169 List_Representation_Info := 1;
170 List_Representation_Info_Mechanisms := True;
173 -- Output copyright notice if full list mode unless we have a list
174 -- file, in which case we defer this so that it is output in the file
176 if (Verbose_Mode or else (Full_List and Full_List_File_Name = null))
177 and then not Debug_Flag_7
181 Write_Str (Gnat_Version_String);
183 Write_Str ("Copyright 1992-" &
185 ", Free Software Foundation, Inc.");
189 -- Before we do anything else, adjust certain global values for
190 -- debug switches which modify their normal natural settings.
193 Ttypes.Bytes_Big_Endian := not Ttypes.Bytes_Big_Endian;
197 Targparm.OpenVMS_On_Target := True;
198 Hostparm.OpenVMS := True;
201 if Debug_Flag_FF then
202 Targparm.Frontend_Layout_On_Target := True;
205 -- We take the default exception mechanism into account
207 if Targparm.ZCX_By_Default_On_Target then
208 if Targparm.GCC_ZCX_Support_On_Target then
209 Exception_Mechanism := Back_End_Exceptions;
212 ("Zero Cost Exceptions not supported on this target");
216 -- Set proper status for overflow checks. We turn on overflow checks
217 -- if -gnatp was not specified, and either -gnato is set or the back
218 -- end takes care of overflow checks. Otherwise we suppress overflow
219 -- checks by default (since front end checks are expensive).
221 if not Opt.Suppress_Checks
222 and then (Opt.Enable_Overflow_Checks
224 (Targparm.Backend_Divide_Checks_On_Target
226 Targparm.Backend_Overflow_Checks_On_Target))
228 Suppress_Options (Overflow_Check) := False;
230 Suppress_Options (Overflow_Check) := True;
233 -- Check we have exactly one source file, this happens only in the case
234 -- where the driver is called directly, it cannot happen when gnat1 is
235 -- invoked from gcc in the normal case.
237 if Osint.Number_Of_Files /= 1 then
240 Osint.Fail ("you must provide one source file");
242 elsif Usage_Requested then
246 Original_Operating_Mode := Operating_Mode;
248 Main_Unit_Node := Cunit (Main_Unit);
249 Main_Kind := Nkind (Unit (Main_Unit_Node));
251 -- Check for suspicious or incorrect body present if we are doing
252 -- semantic checking. We omit this check in syntax only mode, because
253 -- in that case we do not know if we need a body or not.
255 if Operating_Mode /= Check_Syntax
257 ((Main_Kind = N_Package_Declaration
258 and then not Body_Required (Main_Unit_Node))
259 or else (Main_Kind = N_Generic_Package_Declaration
260 and then not Body_Required (Main_Unit_Node))
261 or else Main_Kind = N_Package_Renaming_Declaration
262 or else Main_Kind = N_Subprogram_Renaming_Declaration
263 or else Nkind (Original_Node (Unit (Main_Unit_Node)))
264 in N_Generic_Instantiation)
267 Sname : Unit_Name_Type := Unit_Name (Main_Unit);
268 Src_Ind : Source_File_Index;
269 Fname : File_Name_Type;
271 procedure Bad_Body_Error (Msg : String);
272 -- Issue message for bad body found
278 procedure Bad_Body_Error (Msg : String) is
280 Error_Msg_N (Msg, Main_Unit_Node);
281 Error_Msg_Name_1 := Fname;
283 ("remove incorrect body in file{!", Main_Unit_Node);
286 -- Start of processing for Bad_Body
289 Sname := Unit_Name (Main_Unit);
291 -- If we do not already have a body name, then get the body name
292 -- (but how can we have a body name here ???)
294 if not Is_Body_Name (Sname) then
295 Sname := Get_Body_Name (Sname);
298 Fname := Get_File_Name (Sname, Subunit => False);
299 Src_Ind := Load_Source_File (Fname);
301 -- Case where body is present and it is not a subunit. Exclude
302 -- the subunit case, because it has nothing to do with the
303 -- package we are compiling. It is illegal for a child unit and a
304 -- subunit with the same expanded name (RM 10.2(9)) to appear
305 -- together in a partition, but there is nothing to stop a
306 -- compilation environment from having both, and the test here
307 -- simply allows that. If there is an attempt to include both in
308 -- a partition, this is diagnosed at bind time. In Ada 83 mode
309 -- this is not a warning case.
311 -- Note: if weird file names are being used, we can have
312 -- situation where the file name that supposedly contains body,
313 -- in fact contains a spec, or we can't tell what it contains.
314 -- Skip the error message in these cases.
316 if Src_Ind /= No_Source_File
317 and then Get_Expected_Unit_Type (Fname) = Expect_Body
318 and then not Source_File_Is_Subunit (Src_Ind)
320 Error_Msg_Name_1 := Sname;
322 -- Ada 83 case of a package body being ignored. This is not an
323 -- error as far as the Ada 83 RM is concerned, but it is
324 -- almost certainly not what is wanted so output a warning.
325 -- Give this message only if there were no errors, since
326 -- otherwise it may be incorrect (we may have misinterpreted a
327 -- junk spec as not needing a body when it really does).
329 if Main_Kind = N_Package_Declaration
330 and then Ada_Version = Ada_83
331 and then Operating_Mode = Generate_Code
332 and then Distribution_Stub_Mode /= Generate_Caller_Stub_Body
333 and then not Compilation_Errors
336 ("package % does not require a body?", Main_Unit_Node);
337 Error_Msg_Name_1 := Fname;
339 ("body in file{? will be ignored", Main_Unit_Node);
341 -- Ada 95 cases of a body file present when no body is
342 -- permitted. This we consider to be an error.
345 -- For generic instantiations, we never allow a body
347 if Nkind (Original_Node (Unit (Main_Unit_Node)))
348 in N_Generic_Instantiation
351 ("generic instantiation for % does not allow a body");
353 -- A library unit that is a renaming never allows a body
355 elsif Main_Kind in N_Renaming_Declaration then
357 ("renaming declaration for % does not allow a body!");
359 -- Remaining cases are packages and generic packages. Here
360 -- we only do the test if there are no previous errors,
361 -- because if there are errors, they may lead us to
362 -- incorrectly believe that a package does not allow a body
363 -- when in fact it does.
365 elsif not Compilation_Errors then
366 if Main_Kind = N_Package_Declaration then
368 ("package % does not allow a body!");
370 elsif Main_Kind = N_Generic_Package_Declaration then
372 ("generic package % does not allow a body!");
381 -- Exit if compilation errors detected
383 if Compilation_Errors then
385 Sem_Ch13.Validate_Unchecked_Conversions;
389 -- Generate ALI file if specially requested
391 if Opt.Force_ALI_Tree_File then
392 Write_ALI (Object => False);
396 Exit_Program (E_Errors);
399 -- Set Generate_Code on main unit and its spec. We do this even if are
400 -- not generating code, since Lib-Writ uses this to determine which
401 -- units get written in the ali file.
403 Set_Generate_Code (Main_Unit);
405 -- If we have a corresponding spec, then we need object
406 -- code for the spec unit as well
408 if Nkind (Unit (Main_Unit_Node)) in N_Unit_Body
409 and then not Acts_As_Spec (Main_Unit_Node)
412 (Get_Cunit_Unit_Number (Library_Unit (Main_Unit_Node)));
415 -- Case of no code required to be generated, exit indicating no error
417 if Original_Operating_Mode = Check_Syntax then
423 -- Use a goto instead of calling Exit_Program so that finalization
428 elsif Original_Operating_Mode = Check_Semantics then
429 Back_End_Mode := Declarations_Only;
431 -- All remaining cases are cases in which the user requested that code
432 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if
433 -- we can in fact satisfy this request.
435 -- Cannot generate code if someone has turned off code generation for
436 -- any reason at all. We will try to figure out a reason below.
438 elsif Operating_Mode /= Generate_Code then
439 Back_End_Mode := Skip;
441 -- We can generate code for a subprogram body unless there were missing
442 -- subunits. Note that we always generate code for all generic units (a
443 -- change from some previous versions of GNAT).
445 elsif Main_Kind = N_Subprogram_Body
446 and then not Subunits_Missing
448 Back_End_Mode := Generate_Object;
450 -- We can generate code for a package body unless there are subunits
451 -- missing (note that we always generate code for generic units, which
452 -- is a change from some earlier versions of GNAT).
454 elsif Main_Kind = N_Package_Body
455 and then not Subunits_Missing
457 Back_End_Mode := Generate_Object;
459 -- We can generate code for a package declaration or a subprogram
460 -- declaration only if it does not required a body.
462 elsif (Main_Kind = N_Package_Declaration
464 Main_Kind = N_Subprogram_Declaration)
466 (not Body_Required (Main_Unit_Node)
468 Distribution_Stub_Mode = Generate_Caller_Stub_Body)
470 Back_End_Mode := Generate_Object;
472 -- We can generate code for a generic package declaration of a generic
473 -- subprogram declaration only if does not require a body.
475 elsif (Main_Kind = N_Generic_Package_Declaration
477 Main_Kind = N_Generic_Subprogram_Declaration)
478 and then not Body_Required (Main_Unit_Node)
480 Back_End_Mode := Generate_Object;
482 -- Compilation units that are renamings do not require bodies,
483 -- so we can generate code for them.
485 elsif Main_Kind = N_Package_Renaming_Declaration
486 or else Main_Kind = N_Subprogram_Renaming_Declaration
488 Back_End_Mode := Generate_Object;
490 -- Compilation units that are generic renamings do not require bodies
491 -- so we can generate code for them.
493 elsif Main_Kind in N_Generic_Renaming_Declaration then
494 Back_End_Mode := Generate_Object;
496 -- In all other cases (specs which have bodies, generics, and bodies
497 -- where subunits are missing), we cannot generate code and we generate
498 -- a warning message. Note that generic instantiations are gone at this
499 -- stage since they have been replaced by their instances.
502 Back_End_Mode := Skip;
505 -- At this stage Call_Back_End is set to indicate if the backend should
506 -- be called to generate code. If it is not set, then code generation
507 -- has been turned off, even though code was requested by the original
508 -- command. This is not an error from the user point of view, but it is
509 -- an error from the point of view of the gcc driver, so we must exit
510 -- with an error status.
512 -- We generate an informative message (from the gcc point of view, it
513 -- is an error message, but from the users point of view this is not an
514 -- error, just a consequence of compiling something that cannot
517 if Back_End_Mode = Skip then
518 Write_Str ("cannot generate code for ");
520 Write_Name (Unit_File_Name (Main_Unit));
522 if Subunits_Missing then
523 Write_Str (" (missing subunits)");
525 Write_Str ("to check parent unit");
527 elsif Main_Kind = N_Subunit then
528 Write_Str (" (subunit)");
530 Write_Str ("to check subunit");
532 elsif Main_Kind = N_Subprogram_Declaration then
533 Write_Str (" (subprogram spec)");
535 Write_Str ("to check subprogram spec");
537 -- Generic package body in GNAT implementation mode
539 elsif Main_Kind = N_Package_Body and then GNAT_Mode then
540 Write_Str (" (predefined generic)");
542 Write_Str ("to check predefined generic");
544 -- Only other case is a package spec
547 Write_Str (" (package spec)");
549 Write_Str ("to check package spec");
552 Write_Str (" for errors, use ");
554 if Hostparm.OpenVMS then
555 Write_Str ("/NOLOAD");
557 Write_Str ("-gnatc");
562 Sem_Ch13.Validate_Unchecked_Conversions;
566 Write_ALI (Object => False);
569 -- Exit program with error indication, to kill object file
571 Exit_Program (E_No_Code);
574 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also
575 -- set as indicated by Back_Annotate_Rep_Info being set to True.
577 -- We don't call for annotations on a subunit, because to process those
578 -- the back-end requires that the parent(s) be properly compiled.
580 -- Annotation is suppressed for targets where front-end layout is
581 -- enabled, because the front end determines representations.
583 -- Annotation is also suppressed in the case of compiling for
584 -- the Java VM, since representations are largely symbolic there.
586 if Back_End_Mode = Declarations_Only
587 and then (not Back_Annotate_Rep_Info
588 or else Main_Kind = N_Subunit
589 or else Targparm.Frontend_Layout_On_Target
590 or else Hostparm.Java_VM)
592 Sem_Ch13.Validate_Unchecked_Conversions;
594 Write_ALI (Object => False);
601 -- Ensure that we properly register a dependency on system.ads, since
602 -- even if we do not semantically depend on this, Targparm has read
603 -- system parameters from the system.ads file.
605 Lib.Writ.Ensure_System_Dependency;
607 -- Add dependencies, if any, on preprocessing data file and on
608 -- preprocessing definition file(s).
610 Prepcomp.Add_Dependencies;
612 -- Back end needs to explicitly unlock tables it needs to touch
625 -- Here we call the back end to generate the output code
627 Back_End.Call_Back_End (Back_End_Mode);
629 -- Once the backend is complete, we unlock the names table. This call
630 -- allows a few extra entries, needed for example for the file name for
631 -- the library file output.
635 -- Validate unchecked conversions (using the values for size and
636 -- alignment annotated by the backend where possible).
638 Sem_Ch13.Validate_Unchecked_Conversions;
640 -- Now we complete output of errors, rep info and the tree info. These
641 -- are delayed till now, since it is perfectly possible for gigi to
642 -- generate errors, modify the tree (in particular by setting flags
643 -- indicating that elaboration is required, and also to back annotate
644 -- representation information for List_Rep_Info.
649 -- Only write the library if the backend did not generate any error
650 -- messages. Otherwise signal errors to the driver program so that
651 -- there will be no attempt to generate an object file.
653 if Compilation_Errors then
655 Exit_Program (E_Errors);
658 Write_ALI (Object => (Back_End_Mode = Generate_Object));
660 -- Generate the ASIS tree after writing the ALI file, since in ASIS
661 -- mode, Write_ALI may in fact result in further tree decoration from
662 -- the original tree file. Note that we dump the tree just before
663 -- generating it, so that the dump will exactly reflect what is written
669 -- Finalize name table and we are all done
674 -- Handle fatal internal compiler errors
676 when System.Assertions.Assert_Failure =>
677 Comperr.Compiler_Abort ("Assert_Failure");
679 when Constraint_Error =>
680 Comperr.Compiler_Abort ("Constraint_Error");
682 when Program_Error =>
683 Comperr.Compiler_Abort ("Program_Error");
685 when Storage_Error =>
687 -- Assume this is a bug. If it is real, the message will in any case
688 -- say Storage_Error, giving a strong hint!
690 Comperr.Compiler_Abort ("Storage_Error");
696 -- The outer exception handles an unrecoverable error
699 when Unrecoverable_Error =>
703 Write_Str ("compilation abandoned");
709 Exit_Program (E_Errors);