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 overflow, division by zero and access checks since they
184 -- are handled 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
196 (Suppress
=> (Access_Check
=> True,
197 Alignment_Check
=> True,
198 Division_Check
=> True,
199 Elaboration_Check
=> True,
201 Overflow_Checks_General
=> Suppressed
,
202 Overflow_Checks_Assertions
=> Suppressed
);
204 Dynamic_Elaboration_Checks
:= False;
206 -- Kill debug of generated code, since it messes up sloc values
208 Debug_Generated_Code
:= False;
210 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
211 -- Do we really need to spend time generating xref in CodePeer
212 -- mode??? Consider setting Xref_Active to False.
216 -- Polling mode forced off, since it generates confusing junk
218 Polling_Required
:= False;
220 -- Set operating mode to Generate_Code to benefit from full front-end
221 -- expansion (e.g. generics).
223 Operating_Mode
:= Generate_Code
;
225 -- We need SCIL generation of course
227 Generate_SCIL
:= True;
229 -- Enable assertions and debug pragmas, since they give CodePeer
230 -- valuable extra information.
232 Assertions_Enabled
:= True;
233 Debug_Pragmas_Enabled
:= True;
235 -- Disable all simple value propagation. This is an optimization
236 -- which is valuable for code optimization, and also for generation
237 -- of compiler warnings, but these are being turned off by default,
238 -- and CodePeer generates better messages (referencing original
239 -- variables) this way.
241 Debug_Flag_MM
:= True;
243 -- Set normal RM validity checking, and checking of IN OUT parameters
244 -- (this might give CodePeer more useful checks to analyze, to be
245 -- confirmed???). All other validity checking is turned off, since
246 -- this can generate very complex trees that only confuse CodePeer
247 -- and do not bring enough useful info.
249 Reset_Validity_Check_Options
;
250 Validity_Check_Default
:= True;
251 Validity_Check_In_Out_Params
:= True;
252 Validity_Check_In_Params
:= True;
254 -- Turn off style check options since we are not interested in any
255 -- front-end warnings when we are getting CodePeer output.
257 Reset_Style_Check_Options
;
259 -- Always perform semantics and generate ali files in CodePeer mode,
260 -- so that a gnatmake -c -k will proceed further when possible.
262 Force_ALI_Tree_File
:= True;
263 Try_Semantics
:= True;
266 -- Set Configurable_Run_Time mode if system.ads flag set
268 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
269 Configurable_Run_Time_Mode
:= True;
272 -- Set -gnatR3m mode if debug flag A set
274 if Debug_Flag_AA
then
275 Back_Annotate_Rep_Info
:= True;
276 List_Representation_Info
:= 1;
277 List_Representation_Info_Mechanisms
:= True;
280 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
282 if Debug_Flag_Dot_A
then
283 Ttypes
.Target_Strict_Alignment
:= True;
286 -- Increase size of allocated entities if debug flag -gnatd.N is set
288 if Debug_Flag_Dot_NN
then
289 Atree
.Num_Extension_Nodes
:= Atree
.Num_Extension_Nodes
+ 1;
292 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
293 -- is enabled. The front end's layout phase currently treats types that
294 -- have discriminant-dependent arrays as not being static even when a
295 -- discriminant constraint on the type is static, and this leads to
296 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
298 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
299 Static_Dispatch_Tables
:= False;
302 -- Flip endian mode if -gnatd8 set
305 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
308 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
309 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
310 -- before doing this, so we know if we are in real OpenVMS or not!
312 Opt
.True_VMS_Target
:= Targparm
.OpenVMS_On_Target
;
315 Targparm
.OpenVMS_On_Target
:= True;
316 Hostparm
.OpenVMS
:= True;
319 -- Activate front end layout if debug flag -gnatdF is set
321 if Debug_Flag_FF
then
322 Targparm
.Frontend_Layout_On_Target
:= True;
325 -- Set and check exception mechanism
327 if Targparm
.ZCX_By_Default_On_Target
then
328 Exception_Mechanism
:= Back_End_Exceptions
;
331 -- Set proper status for overflow checks
333 -- If already set (by - gnato or -gnatp) then we have nothing to do
335 if Opt
.Suppress_Options
.Overflow_Checks_General
/= Not_Set
then
338 -- Otherwise set appropriate default mode. Note: at present we set
339 -- SUPPRESSED in all three of the following cases. They are separated
340 -- because in the future we may make different choices.
342 -- By default suppress overflow checks in -gnatg mode
345 Suppress_Options
.Overflow_Checks_General
:= Suppressed
;
346 Suppress_Options
.Overflow_Checks_Assertions
:= Suppressed
;
348 -- If we have backend divide and overflow checks, then by default
349 -- overflow checks are suppressed. Historically this code used to
350 -- activate overflow checks, although no target currently has these
351 -- flags set, so this was dead code anyway.
353 elsif Targparm
.Backend_Divide_Checks_On_Target
355 Targparm
.Backend_Overflow_Checks_On_Target
357 Suppress_Options
.Overflow_Checks_General
:= Suppressed
;
358 Suppress_Options
.Overflow_Checks_Assertions
:= Suppressed
;
360 -- Otherwise for now, default is checks are suppressed. This is subject
361 -- to change in the future, but for now this is the compatible behavior
362 -- with previous versions of GNAT.
365 Suppress_Options
.Overflow_Checks_General
:= Suppressed
;
366 Suppress_Options
.Overflow_Checks_Assertions
:= Suppressed
;
369 -- Set default for atomic synchronization. As this synchronization
370 -- between atomic accesses can be expensive, and not typically needed
371 -- on some targets, an optional target parameter can turn the option
372 -- off. Note Atomic Synchronization is implemented as check.
374 Suppress_Options
.Suppress
(Atomic_Synchronization
) :=
375 not Atomic_Sync_Default
;
377 -- Set switch indicating if we can use N_Expression_With_Actions
379 -- Debug flag -gnatd.X decisively sets usage on
381 if Debug_Flag_Dot_XX
then
382 Use_Expression_With_Actions
:= True;
384 -- Debug flag -gnatd.Y decisively sets usage off
386 elsif Debug_Flag_Dot_YY
then
387 Use_Expression_With_Actions
:= False;
389 -- Otherwise this feature is implemented, so we allow its use
392 Use_Expression_With_Actions
:= True;
395 -- Set switch indicating if back end can handle limited types, and
396 -- guarantee that no incorrect copies are made (e.g. in the context
397 -- of an if or case expression).
399 -- Debug flag -gnatd.L decisively sets usage on
401 if Debug_Flag_Dot_LL
then
402 Back_End_Handles_Limited_Types
:= True;
404 -- If no debug flag, usage off for AAMP, VM, SCIL cases
407 or else VM_Target
/= No_VM
408 or else Generate_SCIL
410 Back_End_Handles_Limited_Types
:= False;
412 -- Otherwise normal gcc back end, for now still turn flag off by
413 -- default, since there are unresolved problems in the front end.
416 Back_End_Handles_Limited_Types
:= False;
419 -- Set switches for formal verification mode
421 if Debug_Flag_Dot_FF
then
425 -- Set strict standard interpretation of compiler permissions
427 if Debug_Flag_Dot_DD
then
428 Strict_Alfa_Mode
:= True;
431 -- Turn off inlining, which would confuse formal verification output
434 Front_End_Inlining
:= False;
435 Inline_Active
:= False;
437 -- Disable front-end optimizations, to keep the tree as close to the
438 -- source code as possible, and also to avoid inconsistencies between
439 -- trees when using different optimization switches.
441 Optimization_Level
:= 0;
443 -- Enable some restrictions systematically to simplify the generated
444 -- code (and ease analysis). Note that restriction checks are also
445 -- disabled in Alfa mode, see Restrict.Check_Restriction, and user
446 -- specified Restrictions pragmas are ignored, see
447 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
449 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
451 -- Suppress all language checks since they are handled implicitly by
452 -- the formal verification backend.
453 -- Turn off dynamic elaboration checks.
454 -- Turn off alignment checks.
455 -- Turn off validity checking.
457 Suppress_Options
:= Suppress_All
;
458 Dynamic_Elaboration_Checks
:= False;
459 Reset_Validity_Check_Options
;
461 -- Kill debug of generated code, since it messes up sloc values
463 Debug_Generated_Code
:= False;
465 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
466 -- as it is needed for computing effects of subprograms in the formal
467 -- verification backend.
471 -- Polling mode forced off, since it generates confusing junk
473 Polling_Required
:= False;
475 -- Set operating mode to Generate_Code, but full front-end expansion
476 -- is not desirable in Alfa mode, so a light expansion is performed
479 Operating_Mode
:= Generate_Code
;
483 Debug_Flag_HH
:= True;
485 -- Disable Expressions_With_Actions nodes
487 -- The gnat2why backend does not deal with Expressions_With_Actions
488 -- in all places (in particular assertions). It is difficult to
489 -- determine in the frontend which cases are allowed, so we disable
490 -- Expressions_With_Actions entirely. Even in the cases where
491 -- gnat2why deals with Expressions_With_Actions, it is easier to
492 -- deal with the original constructs (quantified, conditional and
493 -- case expressions) instead of the rewritten ones.
495 Use_Expression_With_Actions
:= False;
497 -- Enable assertions and debug pragmas, since they give valuable
498 -- extra information for formal verification.
500 Assertions_Enabled
:= True;
501 Debug_Pragmas_Enabled
:= True;
503 -- Turn off style check options since we are not interested in any
504 -- front-end warnings when we are getting Alfa output.
506 Reset_Style_Check_Options
;
508 -- Suppress compiler warnings, since what we are interested in here
509 -- is what formal verification can find out.
511 Warning_Mode
:= Suppress
;
513 -- Suppress the generation of name tables for enumerations, which are
514 -- not needed for formal verification, and fall outside the Alfa
515 -- subset (use of pointers).
517 Global_Discard_Names
:= True;
519 -- Suppress the expansion of tagged types and dispatching calls,
520 -- which lead to the generation of non-Alfa code (use of pointers),
521 -- which is more complex to formally verify than the original source.
523 Tagged_Type_Expansion
:= False;
526 -- If the inlining level has not been set by the user, compute it from
527 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
529 if Inline_Level
= 0 then
530 if Optimization_Level
< 3 then
537 -- Finally capture adjusted value of Suppress_Options as the initial
538 -- value for Scope_Suppress, which will be modified as we move from
539 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
541 Sem
.Scope_Suppress
:= Opt
.Suppress_Options
;
542 end Adjust_Global_Switches
;
548 procedure Check_Bad_Body
is
549 Sname
: Unit_Name_Type
;
550 Src_Ind
: Source_File_Index
;
551 Fname
: File_Name_Type
;
553 procedure Bad_Body_Error
(Msg
: String);
554 -- Issue message for bad body found
560 procedure Bad_Body_Error
(Msg
: String) is
562 Error_Msg_N
(Msg
, Main_Unit_Node
);
563 Error_Msg_File_1
:= Fname
;
564 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
567 -- Start of processing for Check_Bad_Body
570 -- Nothing to do if we are only checking syntax, because we don't know
571 -- enough to know if we require or forbid a body in this case.
573 if Operating_Mode
= Check_Syntax
then
577 -- Check for body not allowed
579 if (Main_Kind
= N_Package_Declaration
580 and then not Body_Required
(Main_Unit_Node
))
581 or else (Main_Kind
= N_Generic_Package_Declaration
582 and then not Body_Required
(Main_Unit_Node
))
583 or else Main_Kind
= N_Package_Renaming_Declaration
584 or else Main_Kind
= N_Subprogram_Renaming_Declaration
585 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
586 in N_Generic_Instantiation
588 Sname
:= Unit_Name
(Main_Unit
);
590 -- If we do not already have a body name, then get the body name
591 -- (but how can we have a body name here???)
593 if not Is_Body_Name
(Sname
) then
594 Sname
:= Get_Body_Name
(Sname
);
597 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
598 Src_Ind
:= Load_Source_File
(Fname
);
600 -- Case where body is present and it is not a subunit. Exclude the
601 -- subunit case, because it has nothing to do with the package we are
602 -- compiling. It is illegal for a child unit and a subunit with the
603 -- same expanded name (RM 10.2(9)) to appear together in a partition,
604 -- but there is nothing to stop a compilation environment from having
605 -- both, and the test here simply allows that. If there is an attempt
606 -- to include both in a partition, this is diagnosed at bind time. In
607 -- Ada 83 mode this is not a warning case.
609 -- Note: if weird file names are being used, we can have a situation
610 -- where the file name that supposedly contains body in fact contains
611 -- a spec, or we can't tell what it contains. Skip the error message
614 -- Also ignore body that is nothing but pragma No_Body; (that's the
615 -- whole point of this pragma, to be used this way and to cause the
616 -- body file to be ignored in this context).
618 if Src_Ind
/= No_Source_File
619 and then Get_Expected_Unit_Type
(Fname
) = Expect_Body
620 and then not Source_File_Is_Subunit
(Src_Ind
)
621 and then not Source_File_Is_No_Body
(Src_Ind
)
623 Errout
.Finalize
(Last_Call
=> False);
625 Error_Msg_Unit_1
:= Sname
;
627 -- Ada 83 case of a package body being ignored. This is not an
628 -- error as far as the Ada 83 RM is concerned, but it is almost
629 -- certainly not what is wanted so output a warning. Give this
630 -- message only if there were no errors, since otherwise it may
631 -- be incorrect (we may have misinterpreted a junk spec as not
632 -- needing a body when it really does).
634 if Main_Kind
= N_Package_Declaration
635 and then Ada_Version
= Ada_83
636 and then Operating_Mode
= Generate_Code
637 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
638 and then not Compilation_Errors
641 ("package $$ does not require a body?", Main_Unit_Node
);
642 Error_Msg_File_1
:= Fname
;
643 Error_Msg_N
("body in file{? will be ignored", Main_Unit_Node
);
645 -- Ada 95 cases of a body file present when no body is
646 -- permitted. This we consider to be an error.
649 -- For generic instantiations, we never allow a body
651 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
652 in N_Generic_Instantiation
655 ("generic instantiation for $$ does not allow a body");
657 -- A library unit that is a renaming never allows a body
659 elsif Main_Kind
in N_Renaming_Declaration
then
661 ("renaming declaration for $$ does not allow a body!");
663 -- Remaining cases are packages and generic packages. Here
664 -- we only do the test if there are no previous errors,
665 -- because if there are errors, they may lead us to
666 -- incorrectly believe that a package does not allow a body
667 -- when in fact it does.
669 elsif not Compilation_Errors
then
670 if Main_Kind
= N_Package_Declaration
then
672 ("package $$ does not allow a body!");
674 elsif Main_Kind
= N_Generic_Package_Declaration
then
676 ("generic package $$ does not allow a body!");
689 procedure Check_Rep_Info
is
691 if List_Representation_Info
/= 0
692 or else List_Representation_Info_Mechanisms
697 ("cannot generate representation information, no code generated");
704 -- Start of processing for Gnat1drv
707 -- This inner block is set up to catch assertion errors and constraint
708 -- errors. Since the code for handling these errors can cause another
709 -- exception to be raised (namely Unrecoverable_Error), we need two
710 -- nested blocks, so that the outer one handles unrecoverable error.
713 -- Initialize all packages. For the most part, these initialization
714 -- calls can be made in any order. Exceptions are as follows:
716 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
717 -- because it initializes a table filled by Scan_Compiler_Arguments.
723 Scan_Compiler_Arguments
;
724 Osint
.Add_Default_Search_Dirs
;
744 Sem_Type
.Init_Interp_Tables
;
746 -- Acquire target parameters from system.ads (source of package System)
751 S
: Source_File_Index
;
755 Name_Buffer
(1 .. 10) := "system.ads";
758 S
:= Load_Source_File
(N
);
760 if S
= No_Source_File
then
762 ("fatal error, run-time library not installed correctly");
763 Write_Line
("cannot locate file system.ads");
764 raise Unrecoverable_Error
;
766 -- Remember source index of system.ads (which was read successfully)
769 System_Source_File_Index
:= S
;
772 Targparm
.Get_Target_Parameters
773 (System_Text
=> Source_Text
(S
),
774 Source_First
=> Source_First
(S
),
775 Source_Last
=> Source_Last
(S
));
777 -- Acquire configuration pragma information from Targparm
779 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
782 Adjust_Global_Switches
;
784 -- Output copyright notice if full list mode unless we have a list
785 -- file, in which case we defer this so that it is output in the file
787 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
788 and then not Debug_Flag_7
792 Write_Str
(Gnat_Version_String
);
794 Write_Str
("Copyright 1992-" & Current_Year
795 & ", Free Software Foundation, Inc.");
799 -- Check we do not have more than one source file, this happens only in
800 -- the case where the driver is called directly, it cannot happen when
801 -- gnat1 is invoked from gcc in the normal case.
803 if Osint
.Number_Of_Files
/= 1 then
806 Osint
.Fail
("you must provide one source file");
808 elsif Usage_Requested
then
812 Original_Operating_Mode
:= Operating_Mode
;
815 -- Exit with errors if the main source could not be parsed. Also, when
816 -- -gnatd.H is present, the source file is not set.
818 if Sinput
.Main_Source_File
= No_Source_File
then
820 -- Handle -gnatd.H debug mode
822 if Debug_Flag_Dot_HH
then
824 -- For -gnatd.H, lock all the tables to keep the convention that
825 -- the backend needs to unlock the tables it wants to touch.
838 -- And all we need to do is to call the back end
840 Back_End
.Call_Back_End
(Back_End
.Generate_Object
);
843 Errout
.Finalize
(Last_Call
=> True);
844 Errout
.Output_Messages
;
845 Exit_Program
(E_Errors
);
848 Main_Unit_Node
:= Cunit
(Main_Unit
);
849 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
852 -- In CodePeer mode we always delete old SCIL files before regenerating
853 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
854 -- files generated by CodePeer itself.
856 if CodePeer_Mode
then
857 Comperr
.Delete_SCIL_Files
;
860 -- Exit if compilation errors detected
862 Errout
.Finalize
(Last_Call
=> False);
864 if Compilation_Errors
then
866 Sem_Ch13
.Validate_Unchecked_Conversions
;
867 Sem_Ch13
.Validate_Address_Clauses
;
868 Sem_Ch13
.Validate_Independence
;
869 Errout
.Output_Messages
;
872 -- Generate ALI file if specially requested
874 if Opt
.Force_ALI_Tree_File
then
875 Write_ALI
(Object
=> False);
879 Errout
.Finalize
(Last_Call
=> True);
880 Exit_Program
(E_Errors
);
883 -- Set Generate_Code on main unit and its spec. We do this even if are
884 -- not generating code, since Lib-Writ uses this to determine which
885 -- units get written in the ali file.
887 Set_Generate_Code
(Main_Unit
);
889 -- If we have a corresponding spec, and it comes from source or it is
890 -- not a generated spec for a child subprogram body, then we need object
891 -- code for the spec unit as well.
893 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
894 and then not Acts_As_Spec
(Main_Unit_Node
)
896 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
897 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
902 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
906 -- Case of no code required to be generated, exit indicating no error
908 if Original_Operating_Mode
= Check_Syntax
then
910 Errout
.Finalize
(Last_Call
=> True);
911 Errout
.Output_Messages
;
916 -- Use a goto instead of calling Exit_Program so that finalization
921 elsif Original_Operating_Mode
= Check_Semantics
then
922 Back_End_Mode
:= Declarations_Only
;
924 -- All remaining cases are cases in which the user requested that code
925 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
926 -- can in fact satisfy this request.
928 -- Cannot generate code if someone has turned off code generation for
929 -- any reason at all. We will try to figure out a reason below.
931 elsif Operating_Mode
/= Generate_Code
then
932 Back_End_Mode
:= Skip
;
934 -- We can generate code for a subprogram body unless there were missing
935 -- subunits. Note that we always generate code for all generic units (a
936 -- change from some previous versions of GNAT).
938 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
939 Back_End_Mode
:= Generate_Object
;
941 -- We can generate code for a package body unless there are subunits
942 -- missing (note that we always generate code for generic units, which
943 -- is a change from some earlier versions of GNAT).
945 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
946 Back_End_Mode
:= Generate_Object
;
948 -- We can generate code for a package declaration or a subprogram
949 -- declaration only if it does not required a body.
951 elsif Nkind_In
(Main_Kind
,
952 N_Package_Declaration
,
953 N_Subprogram_Declaration
)
955 (not Body_Required
(Main_Unit_Node
)
957 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
959 Back_End_Mode
:= Generate_Object
;
961 -- We can generate code for a generic package declaration of a generic
962 -- subprogram declaration only if does not require a body.
964 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
965 N_Generic_Subprogram_Declaration
)
966 and then not Body_Required
(Main_Unit_Node
)
968 Back_End_Mode
:= Generate_Object
;
970 -- Compilation units that are renamings do not require bodies, so we can
971 -- generate code for them.
973 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
974 N_Subprogram_Renaming_Declaration
)
976 Back_End_Mode
:= Generate_Object
;
978 -- Compilation units that are generic renamings do not require bodies
979 -- so we can generate code for them.
981 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
982 Back_End_Mode
:= Generate_Object
;
984 -- It's not an error to generate SCIL for e.g. a spec which has a body
986 elsif CodePeer_Mode
then
987 Back_End_Mode
:= Generate_Object
;
989 -- In all other cases (specs which have bodies, generics, and bodies
990 -- where subunits are missing), we cannot generate code and we generate
991 -- a warning message. Note that generic instantiations are gone at this
992 -- stage since they have been replaced by their instances.
995 Back_End_Mode
:= Skip
;
998 -- At this stage Back_End_Mode is set to indicate if the backend should
999 -- be called to generate code. If it is Skip, then code generation has
1000 -- been turned off, even though code was requested by the original
1001 -- command. This is not an error from the user point of view, but it is
1002 -- an error from the point of view of the gcc driver, so we must exit
1003 -- with an error status.
1005 -- We generate an informative message (from the gcc point of view, it
1006 -- is an error message, but from the users point of view this is not an
1007 -- error, just a consequence of compiling something that cannot
1010 if Back_End_Mode
= Skip
then
1012 Write_Str
("cannot generate code for ");
1013 Write_Str
("file ");
1014 Write_Name
(Unit_File_Name
(Main_Unit
));
1016 if Subunits_Missing
then
1017 Write_Str
(" (missing subunits)");
1020 -- Force generation of ALI file, for backward compatibility
1022 Opt
.Force_ALI_Tree_File
:= True;
1024 elsif Main_Kind
= N_Subunit
then
1025 Write_Str
(" (subunit)");
1028 -- Force generation of ALI file, for backward compatibility
1030 Opt
.Force_ALI_Tree_File
:= True;
1032 elsif Main_Kind
= N_Subprogram_Declaration
then
1033 Write_Str
(" (subprogram spec)");
1036 -- Generic package body in GNAT implementation mode
1038 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
1039 Write_Str
(" (predefined generic)");
1042 -- Force generation of ALI file, for backward compatibility
1044 Opt
.Force_ALI_Tree_File
:= True;
1046 -- Only other case is a package spec
1049 Write_Str
(" (package spec)");
1053 Set_Standard_Output
;
1055 Sem_Ch13
.Validate_Unchecked_Conversions
;
1056 Sem_Ch13
.Validate_Address_Clauses
;
1057 Sem_Ch13
.Validate_Independence
;
1058 Errout
.Finalize
(Last_Call
=> True);
1059 Errout
.Output_Messages
;
1063 -- Generate ALI file if specially requested, or for missing subunits,
1064 -- subunits or predefined generic.
1066 if Opt
.Force_ALI_Tree_File
then
1067 Write_ALI
(Object
=> False);
1073 -- Exit program with error indication, to kill object file
1075 Exit_Program
(E_No_Code
);
1078 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1079 -- as indicated by Back_Annotate_Rep_Info being set to True.
1081 -- We don't call for annotations on a subunit, because to process those
1082 -- the back-end requires that the parent(s) be properly compiled.
1084 -- Annotation is suppressed for targets where front-end layout is
1085 -- enabled, because the front end determines representations.
1087 -- Annotation is also suppressed in the case of compiling for a VM,
1088 -- since representations are largely symbolic there.
1090 if Back_End_Mode
= Declarations_Only
1091 and then (not (Back_Annotate_Rep_Info
or Generate_SCIL
)
1092 or else Main_Kind
= N_Subunit
1093 or else Targparm
.Frontend_Layout_On_Target
1094 or else Targparm
.VM_Target
/= No_VM
)
1096 Sem_Ch13
.Validate_Unchecked_Conversions
;
1097 Sem_Ch13
.Validate_Address_Clauses
;
1098 Sem_Ch13
.Validate_Independence
;
1099 Errout
.Finalize
(Last_Call
=> True);
1100 Errout
.Output_Messages
;
1101 Write_ALI
(Object
=> False);
1109 -- Ensure that we properly register a dependency on system.ads, since
1110 -- even if we do not semantically depend on this, Targparm has read
1111 -- system parameters from the system.ads file.
1113 Lib
.Writ
.Ensure_System_Dependency
;
1115 -- Add dependencies, if any, on preprocessing data file and on
1116 -- preprocessing definition file(s).
1118 Prepcomp
.Add_Dependencies
;
1120 -- Back end needs to explicitly unlock tables it needs to touch
1133 -- Here we call the back end to generate the output code
1135 Generating_Code
:= True;
1136 Back_End
.Call_Back_End
(Back_End_Mode
);
1138 -- Once the backend is complete, we unlock the names table. This call
1139 -- allows a few extra entries, needed for example for the file name for
1140 -- the library file output.
1144 -- Generate the call-graph output of dispatching calls
1146 Exp_CG
.Generate_CG_Output
;
1148 -- Validate unchecked conversions (using the values for size and
1149 -- alignment annotated by the backend where possible).
1151 Sem_Ch13
.Validate_Unchecked_Conversions
;
1153 -- Validate address clauses (again using alignment values annotated
1154 -- by the backend where possible).
1156 Sem_Ch13
.Validate_Address_Clauses
;
1158 -- Validate independence pragmas (again using values annotated by
1159 -- the back end for component layout etc.)
1161 Sem_Ch13
.Validate_Independence
;
1163 -- Now we complete output of errors, rep info and the tree info. These
1164 -- are delayed till now, since it is perfectly possible for gigi to
1165 -- generate errors, modify the tree (in particular by setting flags
1166 -- indicating that elaboration is required, and also to back annotate
1167 -- representation information for List_Rep_Info.
1169 Errout
.Finalize
(Last_Call
=> True);
1170 Errout
.Output_Messages
;
1174 -- Only write the library if the backend did not generate any error
1175 -- messages. Otherwise signal errors to the driver program so that
1176 -- there will be no attempt to generate an object file.
1178 if Compilation_Errors
then
1180 Exit_Program
(E_Errors
);
1183 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
));
1185 if not Compilation_Errors
then
1187 -- In case of ada backends, we need to make sure that the generated
1188 -- object file has a timestamp greater than the ALI file. We do this
1189 -- to make gnatmake happy when checking the ALI and obj timestamps,
1190 -- where it expects the object file being written after the ali file.
1192 -- Gnatmake's assumption is true for gcc platforms where the gcc
1193 -- wrapper needs to call the assembler after calling gnat1, but is
1194 -- not true for ada backends, where the object files are created
1195 -- directly by gnat1 (so are created before the ali file).
1197 Back_End
.Gen_Or_Update_Object_File
;
1200 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1201 -- Write_ALI may in fact result in further tree decoration from the
1202 -- original tree file. Note that we dump the tree just before generating
1203 -- it, so that the dump will exactly reflect what is written out.
1208 -- Finalize name table and we are all done
1213 -- Handle fatal internal compiler errors
1215 when Rtsfind
.RE_Not_Available
=>
1216 Comperr
.Compiler_Abort
("RE_Not_Available");
1218 when System
.Assertions
.Assert_Failure
=>
1219 Comperr
.Compiler_Abort
("Assert_Failure");
1221 when Constraint_Error
=>
1222 Comperr
.Compiler_Abort
("Constraint_Error");
1224 when Program_Error
=>
1225 Comperr
.Compiler_Abort
("Program_Error");
1227 when Storage_Error
=>
1229 -- Assume this is a bug. If it is real, the message will in any case
1230 -- say Storage_Error, giving a strong hint!
1232 Comperr
.Compiler_Abort
("Storage_Error");
1238 -- The outer exception handles an unrecoverable error
1241 when Unrecoverable_Error
=>
1242 Errout
.Finalize
(Last_Call
=> True);
1243 Errout
.Output_Messages
;
1246 Write_Str
("compilation abandoned");
1249 Set_Standard_Output
;
1252 Exit_Program
(E_Errors
);