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 -- Disable validity checks, since it generates code raising
388 -- exceptions for invalid data, which confuses GNATprove. Invalid
389 -- data is directly detected by GNATprove's flow analysis.
391 Validity_Checks_On
:= False;
393 -- Turn off style check options since we are not interested in any
394 -- front-end warnings when we are getting SPARK output.
396 Reset_Style_Check_Options
;
398 -- Suppress the generation of name tables for enumerations, which are
399 -- not needed for formal verification, and fall outside the SPARK
400 -- subset (use of pointers).
402 Global_Discard_Names
:= True;
404 -- Suppress the expansion of tagged types and dispatching calls,
405 -- which lead to the generation of non-SPARK code (use of pointers),
406 -- which is more complex to formally verify than the original source.
408 Tagged_Type_Expansion
:= False;
411 -- Set Configurable_Run_Time mode if system.ads flag set or if the
412 -- special debug flag -gnatdY is set.
414 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
415 Configurable_Run_Time_Mode
:= True;
418 -- Set -gnatR3m mode if debug flag A set
420 if Debug_Flag_AA
then
421 Back_Annotate_Rep_Info
:= True;
422 List_Representation_Info
:= 1;
423 List_Representation_Info_Mechanisms
:= True;
426 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
428 if Debug_Flag_Dot_A
then
429 Ttypes
.Target_Strict_Alignment
:= True;
432 -- Increase size of allocated entities if debug flag -gnatd.N is set
434 if Debug_Flag_Dot_NN
then
435 Atree
.Num_Extension_Nodes
:= Atree
.Num_Extension_Nodes
+ 1;
438 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
439 -- is enabled. The front end's layout phase currently treats types that
440 -- have discriminant-dependent arrays as not being static even when a
441 -- discriminant constraint on the type is static, and this leads to
442 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
444 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
445 Static_Dispatch_Tables
:= False;
448 -- Flip endian mode if -gnatd8 set
451 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
454 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
455 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
456 -- before doing this, so we know if we are in real OpenVMS or not.
458 Opt
.True_VMS_Target
:= Targparm
.OpenVMS_On_Target
;
461 Targparm
.OpenVMS_On_Target
:= True;
462 Hostparm
.OpenVMS
:= True;
465 -- Activate front end layout if debug flag -gnatdF is set
467 if Debug_Flag_FF
then
468 Targparm
.Frontend_Layout_On_Target
:= True;
471 -- Set and check exception mechanism
473 if Targparm
.ZCX_By_Default_On_Target
then
474 Exception_Mechanism
:= Back_End_Exceptions
;
477 -- Set proper status for overflow check mechanism
479 -- If already set (by -gnato or above in SPARK or CodePeer mode) then we
480 -- have nothing to do.
482 if Opt
.Suppress_Options
.Overflow_Mode_General
/= Not_Set
then
485 -- Otherwise set overflow mode defaults
488 -- Otherwise set overflow checks off by default
490 Suppress_Options
.Suppress
(Overflow_Check
) := True;
492 -- Set appropriate default overflow handling mode. Note: at present
493 -- we set STRICT in all three of the following cases. They are
494 -- separated because in the future we may make different choices.
496 -- By default set STRICT mode if -gnatg in effect
499 Suppress_Options
.Overflow_Mode_General
:= Strict
;
500 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
502 -- If we have backend divide and overflow checks, then by default
503 -- overflow checks are STRICT. Historically this code used to also
504 -- activate overflow checks, although no target currently has these
505 -- flags set, so this was dead code anyway.
507 elsif Targparm
.Backend_Divide_Checks_On_Target
509 Targparm
.Backend_Overflow_Checks_On_Target
511 Suppress_Options
.Overflow_Mode_General
:= Strict
;
512 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
514 -- Otherwise for now, default is STRICT mode. This may change in the
515 -- future, but for now this is the compatible behavior with previous
519 Suppress_Options
.Overflow_Mode_General
:= Strict
;
520 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
524 -- Set default for atomic synchronization. As this synchronization
525 -- between atomic accesses can be expensive, and not typically needed
526 -- on some targets, an optional target parameter can turn the option
527 -- off. Note Atomic Synchronization is implemented as check.
529 Suppress_Options
.Suppress
(Atomic_Synchronization
) :=
530 not Atomic_Sync_Default_On_Target
;
532 -- Set switch indicating if back end can handle limited types, and
533 -- guarantee that no incorrect copies are made (e.g. in the context
534 -- of an if or case expression).
536 -- Debug flag -gnatd.L decisively sets usage on
538 if Debug_Flag_Dot_LL
then
539 Back_End_Handles_Limited_Types
:= True;
541 -- If no debug flag, usage off for AAMP, VM, SCIL cases
544 or else VM_Target
/= No_VM
545 or else Generate_SCIL
547 Back_End_Handles_Limited_Types
:= False;
549 -- Otherwise normal gcc back end, for now still turn flag off by
550 -- default, since there are unresolved problems in the front end.
553 Back_End_Handles_Limited_Types
:= False;
556 -- If the inlining level has not been set by the user, compute it from
557 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
559 if Inline_Level
= 0 then
560 if Optimization_Level
< 3 then
567 -- Output warning if -gnateE specified and cannot be supported
569 if Exception_Extra_Info
570 and then Restrict
.No_Exception_Handlers_Set
574 ("warning: extra exception information (-gnateE) was specified");
577 ("warning: this capability is not available in this configuration");
582 -- Finally capture adjusted value of Suppress_Options as the initial
583 -- value for Scope_Suppress, which will be modified as we move from
584 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
586 Sem
.Scope_Suppress
:= Opt
.Suppress_Options
;
587 end Adjust_Global_Switches
;
593 procedure Check_Bad_Body
is
594 Sname
: Unit_Name_Type
;
595 Src_Ind
: Source_File_Index
;
596 Fname
: File_Name_Type
;
598 procedure Bad_Body_Error
(Msg
: String);
599 -- Issue message for bad body found
605 procedure Bad_Body_Error
(Msg
: String) is
607 Error_Msg_N
(Msg
, Main_Unit_Node
);
608 Error_Msg_File_1
:= Fname
;
609 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
612 -- Start of processing for Check_Bad_Body
615 -- Nothing to do if we are only checking syntax, because we don't know
616 -- enough to know if we require or forbid a body in this case.
618 if Operating_Mode
= Check_Syntax
then
622 -- Check for body not allowed
624 if (Main_Kind
= N_Package_Declaration
625 and then not Body_Required
(Main_Unit_Node
))
626 or else (Main_Kind
= N_Generic_Package_Declaration
627 and then not Body_Required
(Main_Unit_Node
))
628 or else Main_Kind
= N_Package_Renaming_Declaration
629 or else Main_Kind
= N_Subprogram_Renaming_Declaration
630 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
631 in N_Generic_Instantiation
633 Sname
:= Unit_Name
(Main_Unit
);
635 -- If we do not already have a body name, then get the body name
636 -- (but how can we have a body name here???)
638 if not Is_Body_Name
(Sname
) then
639 Sname
:= Get_Body_Name
(Sname
);
642 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
643 Src_Ind
:= Load_Source_File
(Fname
);
645 -- Case where body is present and it is not a subunit. Exclude the
646 -- subunit case, because it has nothing to do with the package we are
647 -- compiling. It is illegal for a child unit and a subunit with the
648 -- same expanded name (RM 10.2(9)) to appear together in a partition,
649 -- but there is nothing to stop a compilation environment from having
650 -- both, and the test here simply allows that. If there is an attempt
651 -- to include both in a partition, this is diagnosed at bind time. In
652 -- Ada 83 mode this is not a warning case.
654 -- Note: if weird file names are being used, we can have a situation
655 -- where the file name that supposedly contains body in fact contains
656 -- a spec, or we can't tell what it contains. Skip the error message
659 -- Also ignore body that is nothing but pragma No_Body; (that's the
660 -- whole point of this pragma, to be used this way and to cause the
661 -- body file to be ignored in this context).
663 if Src_Ind
/= No_Source_File
664 and then Get_Expected_Unit_Type
(Fname
) = Expect_Body
665 and then not Source_File_Is_Subunit
(Src_Ind
)
666 and then not Source_File_Is_No_Body
(Src_Ind
)
668 Errout
.Finalize
(Last_Call
=> False);
670 Error_Msg_Unit_1
:= Sname
;
672 -- Ada 83 case of a package body being ignored. This is not an
673 -- error as far as the Ada 83 RM is concerned, but it is almost
674 -- certainly not what is wanted so output a warning. Give this
675 -- message only if there were no errors, since otherwise it may
676 -- be incorrect (we may have misinterpreted a junk spec as not
677 -- needing a body when it really does).
679 if Main_Kind
= N_Package_Declaration
680 and then Ada_Version
= Ada_83
681 and then Operating_Mode
= Generate_Code
682 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
683 and then not Compilation_Errors
686 ("package $$ does not require a body??", Main_Unit_Node
);
687 Error_Msg_File_1
:= Fname
;
688 Error_Msg_N
("body in file{ will be ignored??", Main_Unit_Node
);
690 -- Ada 95 cases of a body file present when no body is
691 -- permitted. This we consider to be an error.
694 -- For generic instantiations, we never allow a body
696 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
697 in N_Generic_Instantiation
700 ("generic instantiation for $$ does not allow a body");
702 -- A library unit that is a renaming never allows a body
704 elsif Main_Kind
in N_Renaming_Declaration
then
706 ("renaming declaration for $$ does not allow a body!");
708 -- Remaining cases are packages and generic packages. Here
709 -- we only do the test if there are no previous errors,
710 -- because if there are errors, they may lead us to
711 -- incorrectly believe that a package does not allow a
712 -- body when in fact it does.
714 elsif not Compilation_Errors
then
715 if Main_Kind
= N_Package_Declaration
then
717 ("package $$ does not allow a body!");
719 elsif Main_Kind
= N_Generic_Package_Declaration
then
721 ("generic package $$ does not allow a body!");
734 procedure Check_Rep_Info
is
736 if List_Representation_Info
/= 0
737 or else List_Representation_Info_Mechanisms
742 ("cannot generate representation information, no code generated");
749 -- Start of processing for Gnat1drv
752 -- This inner block is set up to catch assertion errors and constraint
753 -- errors. Since the code for handling these errors can cause another
754 -- exception to be raised (namely Unrecoverable_Error), we need two
755 -- nested blocks, so that the outer one handles unrecoverable error.
758 -- Initialize all packages. For the most part, these initialization
759 -- calls can be made in any order. Exceptions are as follows:
761 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
762 -- because it initializes a table filled by Scan_Compiler_Arguments.
768 Scan_Compiler_Arguments
;
769 Osint
.Add_Default_Search_Dirs
;
789 Sem_Type
.Init_Interp_Tables
;
791 -- Acquire target parameters from system.ads (source of package System)
796 S
: Source_File_Index
;
800 Name_Buffer
(1 .. 10) := "system.ads";
803 S
:= Load_Source_File
(N
);
805 if S
= No_Source_File
then
807 ("fatal error, run-time library not installed correctly");
808 Write_Line
("cannot locate file system.ads");
809 raise Unrecoverable_Error
;
811 -- Remember source index of system.ads (which was read successfully)
814 System_Source_File_Index
:= S
;
817 Targparm
.Get_Target_Parameters
818 (System_Text
=> Source_Text
(S
),
819 Source_First
=> Source_First
(S
),
820 Source_Last
=> Source_Last
(S
));
822 -- Acquire configuration pragma information from Targparm
824 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
827 Adjust_Global_Switches
;
829 -- Output copyright notice if full list mode unless we have a list
830 -- file, in which case we defer this so that it is output in the file
832 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
833 and then not Debug_Flag_7
837 Write_Str
(Gnat_Version_String
);
839 Write_Str
("Copyright 1992-" & Current_Year
840 & ", Free Software Foundation, Inc.");
844 -- Check we do not have more than one source file, this happens only in
845 -- the case where the driver is called directly, it cannot happen when
846 -- gnat1 is invoked from gcc in the normal case.
848 if Osint
.Number_Of_Files
/= 1 then
851 Osint
.Fail
("you must provide one source file");
853 elsif Usage_Requested
then
857 -- Generate target dependent output file if requested
859 if Target_Dependent_Info_Write_Name
/= null then
860 Set_Targ
.Write_Target_Dependent_Values
;
863 -- Call the front end
865 Original_Operating_Mode
:= Operating_Mode
;
868 -- Exit with errors if the main source could not be parsed.
870 if Sinput
.Main_Source_File
= No_Source_File
then
871 Errout
.Finalize
(Last_Call
=> True);
872 Errout
.Output_Messages
;
873 Exit_Program
(E_Errors
);
876 Main_Unit_Node
:= Cunit
(Main_Unit
);
877 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
880 -- In CodePeer mode we always delete old SCIL files before regenerating
881 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
882 -- files generated by CodePeer itself.
884 if CodePeer_Mode
then
885 Comperr
.Delete_SCIL_Files
;
888 -- Exit if compilation errors detected
890 Errout
.Finalize
(Last_Call
=> False);
892 if Compilation_Errors
then
894 Sem_Ch13
.Validate_Unchecked_Conversions
;
895 Sem_Ch13
.Validate_Address_Clauses
;
896 Sem_Ch13
.Validate_Independence
;
897 Errout
.Output_Messages
;
900 -- Generate ALI file if specially requested
902 if Opt
.Force_ALI_Tree_File
then
903 Write_ALI
(Object
=> False);
907 Errout
.Finalize
(Last_Call
=> True);
908 Exit_Program
(E_Errors
);
911 -- Set Generate_Code on main unit and its spec. We do this even if are
912 -- not generating code, since Lib-Writ uses this to determine which
913 -- units get written in the ali file.
915 Set_Generate_Code
(Main_Unit
);
917 -- If we have a corresponding spec, and it comes from source or it is
918 -- not a generated spec for a child subprogram body, then we need object
919 -- code for the spec unit as well.
921 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
922 and then not Acts_As_Spec
(Main_Unit_Node
)
924 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
925 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
930 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
934 -- Case of no code required to be generated, exit indicating no error
936 if Original_Operating_Mode
= Check_Syntax
then
938 Errout
.Finalize
(Last_Call
=> True);
939 Errout
.Output_Messages
;
944 -- Use a goto instead of calling Exit_Program so that finalization
949 elsif Original_Operating_Mode
= Check_Semantics
then
950 Back_End_Mode
:= Declarations_Only
;
952 -- All remaining cases are cases in which the user requested that code
953 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
954 -- can in fact satisfy this request.
956 -- Cannot generate code if someone has turned off code generation for
957 -- any reason at all. We will try to figure out a reason below.
959 elsif Operating_Mode
/= Generate_Code
then
960 Back_End_Mode
:= Skip
;
962 -- We can generate code for a subprogram body unless there were missing
963 -- subunits. Note that we always generate code for all generic units (a
964 -- change from some previous versions of GNAT).
966 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
967 Back_End_Mode
:= Generate_Object
;
969 -- We can generate code for a package body unless there are subunits
970 -- missing (note that we always generate code for generic units, which
971 -- is a change from some earlier versions of GNAT).
973 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
974 Back_End_Mode
:= Generate_Object
;
976 -- We can generate code for a package declaration or a subprogram
977 -- declaration only if it does not required a body.
979 elsif Nkind_In
(Main_Kind
,
980 N_Package_Declaration
,
981 N_Subprogram_Declaration
)
983 (not Body_Required
(Main_Unit_Node
)
985 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
987 Back_End_Mode
:= Generate_Object
;
989 -- We can generate code for a generic package declaration of a generic
990 -- subprogram declaration only if does not require a body.
992 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
993 N_Generic_Subprogram_Declaration
)
994 and then not Body_Required
(Main_Unit_Node
)
996 Back_End_Mode
:= Generate_Object
;
998 -- Compilation units that are renamings do not require bodies, so we can
999 -- generate code for them.
1001 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
1002 N_Subprogram_Renaming_Declaration
)
1004 Back_End_Mode
:= Generate_Object
;
1006 -- Compilation units that are generic renamings do not require bodies
1007 -- so we can generate code for them.
1009 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
1010 Back_End_Mode
:= Generate_Object
;
1012 -- It is not an error to analyze in CodePeer mode a spec which requires
1013 -- a body, in order to generate SCIL for this spec.
1015 elsif CodePeer_Mode
then
1016 Back_End_Mode
:= Generate_Object
;
1018 -- It is not an error to analyze in GNATprove mode a spec which requires
1019 -- a body, when the body is not available. During frame condition
1020 -- generation, the corresponding ALI file is generated. During
1021 -- analysis, the spec is analyzed.
1023 elsif GNATprove_Mode
then
1024 Back_End_Mode
:= Declarations_Only
;
1026 -- In all other cases (specs which have bodies, generics, and bodies
1027 -- where subunits are missing), we cannot generate code and we generate
1028 -- a warning message. Note that generic instantiations are gone at this
1029 -- stage since they have been replaced by their instances.
1032 Back_End_Mode
:= Skip
;
1035 -- At this stage Back_End_Mode is set to indicate if the backend should
1036 -- be called to generate code. If it is Skip, then code generation has
1037 -- been turned off, even though code was requested by the original
1038 -- command. This is not an error from the user point of view, but it is
1039 -- an error from the point of view of the gcc driver, so we must exit
1040 -- with an error status.
1042 -- We generate an informative message (from the gcc point of view, it
1043 -- is an error message, but from the users point of view this is not an
1044 -- error, just a consequence of compiling something that cannot
1047 if Back_End_Mode
= Skip
then
1049 Write_Str
("cannot generate code for ");
1050 Write_Str
("file ");
1051 Write_Name
(Unit_File_Name
(Main_Unit
));
1053 if Subunits_Missing
then
1054 Write_Str
(" (missing subunits)");
1057 -- Force generation of ALI file, for backward compatibility
1059 Opt
.Force_ALI_Tree_File
:= True;
1061 elsif Main_Kind
= N_Subunit
then
1062 Write_Str
(" (subunit)");
1065 -- Force generation of ALI file, for backward compatibility
1067 Opt
.Force_ALI_Tree_File
:= True;
1069 elsif Main_Kind
= N_Subprogram_Declaration
then
1070 Write_Str
(" (subprogram spec)");
1073 -- Generic package body in GNAT implementation mode
1075 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
1076 Write_Str
(" (predefined generic)");
1079 -- Force generation of ALI file, for backward compatibility
1081 Opt
.Force_ALI_Tree_File
:= True;
1083 -- Only other case is a package spec
1086 Write_Str
(" (package spec)");
1090 Set_Standard_Output
;
1092 Sem_Ch13
.Validate_Unchecked_Conversions
;
1093 Sem_Ch13
.Validate_Address_Clauses
;
1094 Sem_Ch13
.Validate_Independence
;
1095 Errout
.Finalize
(Last_Call
=> True);
1096 Errout
.Output_Messages
;
1100 -- Generate ALI file if specially requested, or for missing subunits,
1101 -- subunits or predefined generic.
1103 if Opt
.Force_ALI_Tree_File
then
1104 Write_ALI
(Object
=> False);
1110 -- Exit program with error indication, to kill object file
1112 Exit_Program
(E_No_Code
);
1115 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1116 -- as indicated by Back_Annotate_Rep_Info being set to True.
1118 -- We don't call for annotations on a subunit, because to process those
1119 -- the back-end requires that the parent(s) be properly compiled.
1121 -- Annotation is suppressed for targets where front-end layout is
1122 -- enabled, because the front end determines representations.
1124 -- Annotation is also suppressed in the case of compiling for a VM,
1125 -- since representations are largely symbolic there.
1127 if Back_End_Mode
= Declarations_Only
1129 (not (Back_Annotate_Rep_Info
or Generate_SCIL
or GNATprove_Mode
)
1130 or else Main_Kind
= N_Subunit
1131 or else Targparm
.Frontend_Layout_On_Target
1132 or else Targparm
.VM_Target
/= No_VM
)
1134 Sem_Ch13
.Validate_Unchecked_Conversions
;
1135 Sem_Ch13
.Validate_Address_Clauses
;
1136 Sem_Ch13
.Validate_Independence
;
1137 Errout
.Finalize
(Last_Call
=> True);
1138 Errout
.Output_Messages
;
1139 Write_ALI
(Object
=> False);
1147 -- Ensure that we properly register a dependency on system.ads, since
1148 -- even if we do not semantically depend on this, Targparm has read
1149 -- system parameters from the system.ads file.
1151 Lib
.Writ
.Ensure_System_Dependency
;
1153 -- Add dependencies, if any, on preprocessing data file and on
1154 -- preprocessing definition file(s).
1156 Prepcomp
.Add_Dependencies
;
1158 -- Back end needs to explicitly unlock tables it needs to touch
1171 -- Here we call the back end to generate the output code
1173 Generating_Code
:= True;
1174 Back_End
.Call_Back_End
(Back_End_Mode
);
1176 -- Once the backend is complete, we unlock the names table. This call
1177 -- allows a few extra entries, needed for example for the file name for
1178 -- the library file output.
1182 -- Generate the call-graph output of dispatching calls
1184 Exp_CG
.Generate_CG_Output
;
1186 -- Validate unchecked conversions (using the values for size and
1187 -- alignment annotated by the backend where possible).
1189 Sem_Ch13
.Validate_Unchecked_Conversions
;
1191 -- Validate address clauses (again using alignment values annotated
1192 -- by the backend where possible).
1194 Sem_Ch13
.Validate_Address_Clauses
;
1196 -- Validate independence pragmas (again using values annotated by
1197 -- the back end for component layout etc.)
1199 Sem_Ch13
.Validate_Independence
;
1201 -- Now we complete output of errors, rep info and the tree info. These
1202 -- are delayed till now, since it is perfectly possible for gigi to
1203 -- generate errors, modify the tree (in particular by setting flags
1204 -- indicating that elaboration is required, and also to back annotate
1205 -- representation information for List_Rep_Info.
1207 Errout
.Finalize
(Last_Call
=> True);
1208 Errout
.Output_Messages
;
1209 List_Rep_Info
(Ttypes
.Bytes_Big_Endian
);
1212 -- Only write the library if the backend did not generate any error
1213 -- messages. Otherwise signal errors to the driver program so that
1214 -- there will be no attempt to generate an object file.
1216 if Compilation_Errors
then
1218 Exit_Program
(E_Errors
);
1221 -- In GNATprove mode, an "object" file is always generated as the
1222 -- result of calling gnat1 or gnat2why, although this is not the
1223 -- same as the object file produced for compilation.
1225 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
1226 or else GNATprove_Mode
));
1228 if not Compilation_Errors
then
1230 -- In case of ada backends, we need to make sure that the generated
1231 -- object file has a timestamp greater than the ALI file. We do this
1232 -- to make gnatmake happy when checking the ALI and obj timestamps,
1233 -- where it expects the object file being written after the ali file.
1235 -- Gnatmake's assumption is true for gcc platforms where the gcc
1236 -- wrapper needs to call the assembler after calling gnat1, but is
1237 -- not true for ada backends, where the object files are created
1238 -- directly by gnat1 (so are created before the ali file).
1240 Back_End
.Gen_Or_Update_Object_File
;
1243 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1244 -- Write_ALI may in fact result in further tree decoration from the
1245 -- original tree file. Note that we dump the tree just before generating
1246 -- it, so that the dump will exactly reflect what is written out.
1251 -- Finalize name table and we are all done
1256 -- Handle fatal internal compiler errors
1258 when Rtsfind
.RE_Not_Available
=>
1259 Comperr
.Compiler_Abort
("RE_Not_Available");
1261 when System
.Assertions
.Assert_Failure
=>
1262 Comperr
.Compiler_Abort
("Assert_Failure");
1264 when Constraint_Error
=>
1265 Comperr
.Compiler_Abort
("Constraint_Error");
1267 when Program_Error
=>
1268 Comperr
.Compiler_Abort
("Program_Error");
1270 when Storage_Error
=>
1272 -- Assume this is a bug. If it is real, the message will in any case
1273 -- say Storage_Error, giving a strong hint.
1275 Comperr
.Compiler_Abort
("Storage_Error");
1281 -- The outer exception handles an unrecoverable error
1284 when Unrecoverable_Error
=>
1285 Errout
.Finalize
(Last_Call
=> True);
1286 Errout
.Output_Messages
;
1289 Write_Str
("compilation abandoned");
1292 Set_Standard_Output
;
1295 Exit_Program
(E_Errors
);