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 -- Disable CodePeer_Mode in Check_Syntax, since we need front-end
123 if Operating_Mode
= Check_Syntax
then
124 CodePeer_Mode
:= False;
127 -- Set ASIS mode if -gnatt and -gnatc are set
129 if Operating_Mode
= Check_Semantics
and then Tree_Output
then
132 -- Turn off inlining in ASIS mode, since ASIS cannot handle the extra
133 -- information in the trees caused by inlining being active.
135 -- More specifically, the tree seems to be malformed from the ASIS
136 -- point of view if -gnatc and -gnatn appear together???
138 Inline_Active
:= False;
140 -- Turn off SCIL generation and CodePeer mode in semantics mode,
141 -- since SCIL requires front-end expansion.
143 Generate_SCIL
:= False;
144 CodePeer_Mode
:= False;
147 -- SCIL mode needs to disable front-end inlining since the generated
148 -- trees (in particular order and consistency between specs compiled
149 -- as part of a main unit or as part of a with-clause) are causing
152 if Generate_SCIL
then
153 Front_End_Inlining
:= False;
156 -- Tune settings for optimal SCIL generation in CodePeer mode
158 if CodePeer_Mode
then
160 -- Turn off inlining, confuses CodePeer output and gains nothing
162 Front_End_Inlining
:= False;
163 Inline_Active
:= False;
165 -- Disable front-end optimizations, to keep the tree as close to the
166 -- source code as possible, and also to avoid inconsistencies between
167 -- trees when using different optimization switches.
169 Optimization_Level
:= 0;
171 -- Enable some restrictions systematically to simplify the generated
172 -- code (and ease analysis). Note that restriction checks are also
173 -- disabled in CodePeer mode, see Restrict.Check_Restriction, and
174 -- user specified Restrictions pragmas are ignored, see
175 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
177 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
178 Restrict
.Restrictions
.Set
(No_Task_Hierarchy
) := True;
179 Restrict
.Restrictions
.Set
(No_Abort_Statements
) := True;
180 Restrict
.Restrictions
.Set
(Max_Asynchronous_Select_Nesting
) := True;
181 Restrict
.Restrictions
.Value
(Max_Asynchronous_Select_Nesting
) := 0;
183 -- Suppress division by zero and access checks since they are handled
184 -- implicitly by CodePeer.
186 -- Turn off dynamic elaboration checks: generates inconsistencies in
187 -- trees between specs compiled as part of a main unit or as part of
190 -- Turn off alignment checks: these cannot be proved statically by
191 -- CodePeer and generate false positives.
193 -- Enable all other language checks
195 Suppress_Options
.Suppress
:=
196 (Access_Check
=> True,
197 Alignment_Check
=> True,
198 Division_Check
=> True,
199 Elaboration_Check
=> True,
202 Dynamic_Elaboration_Checks
:= False;
204 -- Set STRICT mode for overflow checks if not set explicitly. This
205 -- prevents suppressing of overflow checks by default, in code down
208 if Suppress_Options
.Overflow_Mode_General
= Not_Set
then
209 Suppress_Options
.Overflow_Mode_General
:= Strict
;
210 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
213 -- CodePeer handles division and overflow checks directly, based on
214 -- the marks set by the frontend, hence no special expansion should
215 -- be performed in the frontend for division and overflow checks.
217 Backend_Divide_Checks_On_Target
:= True;
218 Backend_Overflow_Checks_On_Target
:= True;
220 -- Kill debug of generated code, since it messes up sloc values
222 Debug_Generated_Code
:= False;
224 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
225 -- Do we really need to spend time generating xref in CodePeer
226 -- mode??? Consider setting Xref_Active to False.
230 -- Polling mode forced off, since it generates confusing junk
232 Polling_Required
:= False;
234 -- Set operating mode to Generate_Code to benefit from full front-end
235 -- expansion (e.g. generics).
237 Operating_Mode
:= Generate_Code
;
239 -- We need SCIL generation of course
241 Generate_SCIL
:= True;
243 -- Enable assertions and debug pragmas, since they give CodePeer
244 -- valuable extra information.
246 Assertions_Enabled
:= True;
247 Debug_Pragmas_Enabled
:= True;
249 -- Disable all simple value propagation. This is an optimization
250 -- which is valuable for code optimization, and also for generation
251 -- of compiler warnings, but these are being turned off by default,
252 -- and CodePeer generates better messages (referencing original
253 -- variables) this way.
255 Debug_Flag_MM
:= True;
257 -- Set normal RM validity checking, and checking of IN OUT parameters
258 -- (this might give CodePeer more useful checks to analyze, to be
259 -- confirmed???). All other validity checking is turned off, since
260 -- this can generate very complex trees that only confuse CodePeer
261 -- and do not bring enough useful info.
263 Reset_Validity_Check_Options
;
264 Validity_Check_Default
:= True;
265 Validity_Check_In_Out_Params
:= True;
266 Validity_Check_In_Params
:= True;
268 -- Turn off style check options since we are not interested in any
269 -- front-end warnings when we are getting CodePeer output.
271 Reset_Style_Check_Options
;
273 -- Always perform semantics and generate ali files in CodePeer mode,
274 -- so that a gnatmake -c -k will proceed further when possible.
276 Force_ALI_Tree_File
:= True;
277 Try_Semantics
:= True;
279 -- Make the Ada front-end more liberal so that the compiler will
280 -- allow illegal code that is allowed by other compilers. CodePeer
281 -- is in the business of finding problems, not enforcing rules!
282 -- This is useful when using CodePeer mode with other compilers.
284 Relaxed_RM_Semantics
:= True;
287 if Relaxed_RM_Semantics
then
288 Overriding_Renamings
:= True;
291 -- Set switches for formal verification mode
293 if Debug_Flag_Dot_VV
then
294 Formal_Extensions
:= True;
297 -- Enable Alfa_Mode when using -gnatd.F switch
299 if Debug_Flag_Dot_FF
then
303 -- Alfa_Mode is also activated by default in the gnat2why executable
307 -- Set strict standard interpretation of compiler permissions
309 if Debug_Flag_Dot_DD
then
310 Strict_Alfa_Mode
:= True;
313 -- Distinguish between the two modes of gnat2why: frame condition
314 -- generation (generation of ALI files) and translation of Why (no
315 -- ALI files generated). This is done with the switch -gnatd.G,
316 -- which activates frame condition mode. The other changes in
317 -- behavior depending on this switch are done in gnat2why directly.
319 if Debug_Flag_Dot_GG
then
320 Frame_Condition_Mode
:= True;
322 Opt
.Disable_ALI_File
:= True;
325 -- Turn off inlining, which would confuse formal verification output
328 Front_End_Inlining
:= False;
329 Inline_Active
:= False;
331 -- Disable front-end optimizations, to keep the tree as close to the
332 -- source code as possible, and also to avoid inconsistencies between
333 -- trees when using different optimization switches.
335 Optimization_Level
:= 0;
337 -- Enable some restrictions systematically to simplify the generated
338 -- code (and ease analysis). Note that restriction checks are also
339 -- disabled in Alfa mode, see Restrict.Check_Restriction, and user
340 -- specified Restrictions pragmas are ignored, see
341 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
343 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
345 -- Note: at this point we used to suppress various checks, but that
346 -- is not what we want. We need the semantic processing for these
347 -- checks (which will set flags like Do_Overflow_Check, showing the
348 -- points at which potential checks are required semantically). We
349 -- don't want the expansion associated with these checks, but that
350 -- happens anyway because this expansion is simply not done in the
351 -- Alfa version of the expander.
353 -- Turn off dynamic elaboration checks: generates inconsistencies in
354 -- trees between specs compiled as part of a main unit or as part of
357 Dynamic_Elaboration_Checks
:= False;
359 -- Set STRICT mode for overflow checks if not set explicitly. This
360 -- prevents suppressing of overflow checks by default, in code down
363 if Suppress_Options
.Overflow_Mode_General
= Not_Set
then
364 Suppress_Options
.Overflow_Mode_General
:= Strict
;
365 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
368 -- Kill debug of generated code, since it messes up sloc values
370 Debug_Generated_Code
:= False;
372 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
373 -- as it is needed for computing effects of subprograms in the formal
374 -- verification backend.
378 -- Polling mode forced off, since it generates confusing junk
380 Polling_Required
:= False;
382 -- Set operating mode to Generate_Code, but full front-end expansion
383 -- is not desirable in Alfa mode, so a light expansion is performed
386 Operating_Mode
:= Generate_Code
;
390 Debug_Flag_HH
:= True;
392 -- Disable Expressions_With_Actions nodes
394 -- The gnat2why backend does not deal with Expressions_With_Actions
395 -- in all places (in particular assertions). It is difficult to
396 -- determine in the frontend which cases are allowed, so we disable
397 -- Expressions_With_Actions entirely. Even in the cases where
398 -- gnat2why deals with Expressions_With_Actions, it is easier to
399 -- deal with the original constructs (quantified, conditional and
400 -- case expressions) instead of the rewritten ones.
402 Use_Expression_With_Actions
:= False;
404 -- Enable assertions and debug pragmas, since they give valuable
405 -- extra information for formal verification.
407 Assertions_Enabled
:= True;
408 Debug_Pragmas_Enabled
:= True;
410 -- Turn off style check options since we are not interested in any
411 -- front-end warnings when we are getting Alfa output.
413 Reset_Style_Check_Options
;
415 -- Suppress compiler warnings, since what we are interested in here
416 -- is what formal verification can find out.
418 Warning_Mode
:= Suppress
;
420 -- Suppress the generation of name tables for enumerations, which are
421 -- not needed for formal verification, and fall outside the Alfa
422 -- subset (use of pointers).
424 Global_Discard_Names
:= True;
426 -- Suppress the expansion of tagged types and dispatching calls,
427 -- which lead to the generation of non-Alfa code (use of pointers),
428 -- which is more complex to formally verify than the original source.
430 Tagged_Type_Expansion
:= False;
434 -- Set Configurable_Run_Time mode if system.ads flag set
436 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
437 Configurable_Run_Time_Mode
:= True;
440 -- Set -gnatR3m mode if debug flag A set
442 if Debug_Flag_AA
then
443 Back_Annotate_Rep_Info
:= True;
444 List_Representation_Info
:= 1;
445 List_Representation_Info_Mechanisms
:= True;
448 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
450 if Debug_Flag_Dot_A
then
451 Ttypes
.Target_Strict_Alignment
:= True;
454 -- Increase size of allocated entities if debug flag -gnatd.N is set
456 if Debug_Flag_Dot_NN
then
457 Atree
.Num_Extension_Nodes
:= Atree
.Num_Extension_Nodes
+ 1;
460 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
461 -- is enabled. The front end's layout phase currently treats types that
462 -- have discriminant-dependent arrays as not being static even when a
463 -- discriminant constraint on the type is static, and this leads to
464 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
466 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
467 Static_Dispatch_Tables
:= False;
470 -- Flip endian mode if -gnatd8 set
473 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
476 -- Deal with forcing OpenVMS switches True if debug flag M is set, but
477 -- record the setting of Targparm.Open_VMS_On_Target in True_VMS_Target
478 -- before doing this, so we know if we are in real OpenVMS or not!
480 Opt
.True_VMS_Target
:= Targparm
.OpenVMS_On_Target
;
483 Targparm
.OpenVMS_On_Target
:= True;
484 Hostparm
.OpenVMS
:= True;
487 -- Activate front end layout if debug flag -gnatdF is set
489 if Debug_Flag_FF
then
490 Targparm
.Frontend_Layout_On_Target
:= True;
493 -- Set and check exception mechanism
495 if Targparm
.ZCX_By_Default_On_Target
then
496 Exception_Mechanism
:= Back_End_Exceptions
;
499 -- Set proper status for overflow check mechanism
501 -- If already set (by -gnato or above in Alfa or CodePeer mode) then we
502 -- have nothing to do.
504 if Opt
.Suppress_Options
.Overflow_Mode_General
/= Not_Set
then
507 -- Otherwise set overflow mode defaults
510 -- Otherwise set overflow checks off by default
512 Suppress_Options
.Suppress
(Overflow_Check
) := True;
514 -- Set appropriate default overflow handling mode. Note: at present
515 -- we set STRICT in all three of the following cases. They are
516 -- separated because in the future we may make different choices.
518 -- By default set STRICT mode if -gnatg in effect
521 Suppress_Options
.Overflow_Mode_General
:= Strict
;
522 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
524 -- If we have backend divide and overflow checks, then by default
525 -- overflow checks are STRICT. Historically this code used to also
526 -- activate overflow checks, although no target currently has these
527 -- flags set, so this was dead code anyway.
529 elsif Targparm
.Backend_Divide_Checks_On_Target
531 Targparm
.Backend_Overflow_Checks_On_Target
533 Suppress_Options
.Overflow_Mode_General
:= Strict
;
534 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
536 -- Otherwise for now, default is STRICT mode. This may change in the
537 -- future, but for now this is the compatible behavior with previous
541 Suppress_Options
.Overflow_Mode_General
:= Strict
;
542 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
546 -- Set default for atomic synchronization. As this synchronization
547 -- between atomic accesses can be expensive, and not typically needed
548 -- on some targets, an optional target parameter can turn the option
549 -- off. Note Atomic Synchronization is implemented as check.
551 Suppress_Options
.Suppress
(Atomic_Synchronization
) :=
552 not Atomic_Sync_Default_On_Target
;
554 -- Set switch indicating if we can use N_Expression_With_Actions
556 -- Debug flag -gnatd.X decisively sets usage on
558 if Debug_Flag_Dot_XX
then
559 Use_Expression_With_Actions
:= True;
561 -- Debug flag -gnatd.Y decisively sets usage off
563 elsif Debug_Flag_Dot_YY
then
564 Use_Expression_With_Actions
:= False;
566 -- Otherwise this feature is implemented, so we allow its use
569 Use_Expression_With_Actions
:= True;
572 -- Set switch indicating if back end can handle limited types, and
573 -- guarantee that no incorrect copies are made (e.g. in the context
574 -- of an if or case expression).
576 -- Debug flag -gnatd.L decisively sets usage on
578 if Debug_Flag_Dot_LL
then
579 Back_End_Handles_Limited_Types
:= True;
581 -- If no debug flag, usage off for AAMP, VM, SCIL cases
584 or else VM_Target
/= No_VM
585 or else Generate_SCIL
587 Back_End_Handles_Limited_Types
:= False;
589 -- Otherwise normal gcc back end, for now still turn flag off by
590 -- default, since there are unresolved problems in the front end.
593 Back_End_Handles_Limited_Types
:= False;
596 -- If the inlining level has not been set by the user, compute it from
597 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
599 if Inline_Level
= 0 then
600 if Optimization_Level
< 3 then
607 -- Finally capture adjusted value of Suppress_Options as the initial
608 -- value for Scope_Suppress, which will be modified as we move from
609 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
611 Sem
.Scope_Suppress
:= Opt
.Suppress_Options
;
612 end Adjust_Global_Switches
;
618 procedure Check_Bad_Body
is
619 Sname
: Unit_Name_Type
;
620 Src_Ind
: Source_File_Index
;
621 Fname
: File_Name_Type
;
623 procedure Bad_Body_Error
(Msg
: String);
624 -- Issue message for bad body found
630 procedure Bad_Body_Error
(Msg
: String) is
632 Error_Msg_N
(Msg
, Main_Unit_Node
);
633 Error_Msg_File_1
:= Fname
;
634 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
637 -- Start of processing for Check_Bad_Body
640 -- Nothing to do if we are only checking syntax, because we don't know
641 -- enough to know if we require or forbid a body in this case.
643 if Operating_Mode
= Check_Syntax
then
647 -- Check for body not allowed
649 if (Main_Kind
= N_Package_Declaration
650 and then not Body_Required
(Main_Unit_Node
))
651 or else (Main_Kind
= N_Generic_Package_Declaration
652 and then not Body_Required
(Main_Unit_Node
))
653 or else Main_Kind
= N_Package_Renaming_Declaration
654 or else Main_Kind
= N_Subprogram_Renaming_Declaration
655 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
656 in N_Generic_Instantiation
658 Sname
:= Unit_Name
(Main_Unit
);
660 -- If we do not already have a body name, then get the body name
661 -- (but how can we have a body name here???)
663 if not Is_Body_Name
(Sname
) then
664 Sname
:= Get_Body_Name
(Sname
);
667 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
668 Src_Ind
:= Load_Source_File
(Fname
);
670 -- Case where body is present and it is not a subunit. Exclude the
671 -- subunit case, because it has nothing to do with the package we are
672 -- compiling. It is illegal for a child unit and a subunit with the
673 -- same expanded name (RM 10.2(9)) to appear together in a partition,
674 -- but there is nothing to stop a compilation environment from having
675 -- both, and the test here simply allows that. If there is an attempt
676 -- to include both in a partition, this is diagnosed at bind time. In
677 -- Ada 83 mode this is not a warning case.
679 -- Note: if weird file names are being used, we can have a situation
680 -- where the file name that supposedly contains body in fact contains
681 -- a spec, or we can't tell what it contains. Skip the error message
684 -- Also ignore body that is nothing but pragma No_Body; (that's the
685 -- whole point of this pragma, to be used this way and to cause the
686 -- body file to be ignored in this context).
688 if Src_Ind
/= No_Source_File
689 and then Get_Expected_Unit_Type
(Fname
) = Expect_Body
690 and then not Source_File_Is_Subunit
(Src_Ind
)
691 and then not Source_File_Is_No_Body
(Src_Ind
)
693 Errout
.Finalize
(Last_Call
=> False);
695 Error_Msg_Unit_1
:= Sname
;
697 -- Ada 83 case of a package body being ignored. This is not an
698 -- error as far as the Ada 83 RM is concerned, but it is almost
699 -- certainly not what is wanted so output a warning. Give this
700 -- message only if there were no errors, since otherwise it may
701 -- be incorrect (we may have misinterpreted a junk spec as not
702 -- needing a body when it really does).
704 if Main_Kind
= N_Package_Declaration
705 and then Ada_Version
= Ada_83
706 and then Operating_Mode
= Generate_Code
707 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
708 and then not Compilation_Errors
711 ("package $$ does not require a body??", Main_Unit_Node
);
712 Error_Msg_File_1
:= Fname
;
713 Error_Msg_N
("body in file{ will be ignored??", Main_Unit_Node
);
715 -- Ada 95 cases of a body file present when no body is
716 -- permitted. This we consider to be an error.
719 -- For generic instantiations, we never allow a body
721 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
722 in N_Generic_Instantiation
725 ("generic instantiation for $$ does not allow a body");
727 -- A library unit that is a renaming never allows a body
729 elsif Main_Kind
in N_Renaming_Declaration
then
731 ("renaming declaration for $$ does not allow a body!");
733 -- Remaining cases are packages and generic packages. Here
734 -- we only do the test if there are no previous errors,
735 -- because if there are errors, they may lead us to
736 -- incorrectly believe that a package does not allow a body
737 -- when in fact it does.
739 elsif not Compilation_Errors
then
740 if Main_Kind
= N_Package_Declaration
then
742 ("package $$ does not allow a body!");
744 elsif Main_Kind
= N_Generic_Package_Declaration
then
746 ("generic package $$ does not allow a body!");
759 procedure Check_Rep_Info
is
761 if List_Representation_Info
/= 0
762 or else List_Representation_Info_Mechanisms
767 ("cannot generate representation information, no code generated");
774 -- Start of processing for Gnat1drv
777 -- This inner block is set up to catch assertion errors and constraint
778 -- errors. Since the code for handling these errors can cause another
779 -- exception to be raised (namely Unrecoverable_Error), we need two
780 -- nested blocks, so that the outer one handles unrecoverable error.
783 -- Initialize all packages. For the most part, these initialization
784 -- calls can be made in any order. Exceptions are as follows:
786 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
787 -- because it initializes a table filled by Scan_Compiler_Arguments.
793 Scan_Compiler_Arguments
;
794 Osint
.Add_Default_Search_Dirs
;
814 Sem_Type
.Init_Interp_Tables
;
816 -- Acquire target parameters from system.ads (source of package System)
821 S
: Source_File_Index
;
825 Name_Buffer
(1 .. 10) := "system.ads";
828 S
:= Load_Source_File
(N
);
830 if S
= No_Source_File
then
832 ("fatal error, run-time library not installed correctly");
833 Write_Line
("cannot locate file system.ads");
834 raise Unrecoverable_Error
;
836 -- Remember source index of system.ads (which was read successfully)
839 System_Source_File_Index
:= S
;
842 Targparm
.Get_Target_Parameters
843 (System_Text
=> Source_Text
(S
),
844 Source_First
=> Source_First
(S
),
845 Source_Last
=> Source_Last
(S
));
847 -- Acquire configuration pragma information from Targparm
849 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
852 Adjust_Global_Switches
;
854 -- Output copyright notice if full list mode unless we have a list
855 -- file, in which case we defer this so that it is output in the file
857 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
858 and then not Debug_Flag_7
862 Write_Str
(Gnat_Version_String
);
864 Write_Str
("Copyright 1992-" & Current_Year
865 & ", Free Software Foundation, Inc.");
869 -- Check we do not have more than one source file, this happens only in
870 -- the case where the driver is called directly, it cannot happen when
871 -- gnat1 is invoked from gcc in the normal case.
873 if Osint
.Number_Of_Files
/= 1 then
876 Osint
.Fail
("you must provide one source file");
878 elsif Usage_Requested
then
882 -- Generate target dependent output file if requested
884 if Target_Dependent_Info_Write
then
885 Set_Targ
.Write_Target_Dependent_Values
;
888 -- Call the front end
890 Original_Operating_Mode
:= Operating_Mode
;
893 -- Exit with errors if the main source could not be parsed. Also, when
894 -- -gnatd.H is present, the source file is not set.
896 if Sinput
.Main_Source_File
= No_Source_File
then
898 -- Handle -gnatd.H debug mode
900 if Debug_Flag_Dot_HH
then
902 -- For -gnatd.H, lock all the tables to keep the convention that
903 -- the backend needs to unlock the tables it wants to touch.
916 -- And all we need to do is to call the back end
918 Back_End
.Call_Back_End
(Back_End
.Generate_Object
);
921 Errout
.Finalize
(Last_Call
=> True);
922 Errout
.Output_Messages
;
923 Exit_Program
(E_Errors
);
926 Main_Unit_Node
:= Cunit
(Main_Unit
);
927 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
930 -- In CodePeer mode we always delete old SCIL files before regenerating
931 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
932 -- files generated by CodePeer itself.
934 if CodePeer_Mode
then
935 Comperr
.Delete_SCIL_Files
;
938 -- Exit if compilation errors detected
940 Errout
.Finalize
(Last_Call
=> False);
942 if Compilation_Errors
then
944 Sem_Ch13
.Validate_Unchecked_Conversions
;
945 Sem_Ch13
.Validate_Address_Clauses
;
946 Sem_Ch13
.Validate_Independence
;
947 Errout
.Output_Messages
;
950 -- Generate ALI file if specially requested
952 if Opt
.Force_ALI_Tree_File
then
953 Write_ALI
(Object
=> False);
957 Errout
.Finalize
(Last_Call
=> True);
958 Exit_Program
(E_Errors
);
961 -- Set Generate_Code on main unit and its spec. We do this even if are
962 -- not generating code, since Lib-Writ uses this to determine which
963 -- units get written in the ali file.
965 Set_Generate_Code
(Main_Unit
);
967 -- If we have a corresponding spec, and it comes from source or it is
968 -- not a generated spec for a child subprogram body, then we need object
969 -- code for the spec unit as well.
971 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
972 and then not Acts_As_Spec
(Main_Unit_Node
)
974 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
975 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
980 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
984 -- Case of no code required to be generated, exit indicating no error
986 if Original_Operating_Mode
= Check_Syntax
then
988 Errout
.Finalize
(Last_Call
=> True);
989 Errout
.Output_Messages
;
994 -- Use a goto instead of calling Exit_Program so that finalization
999 elsif Original_Operating_Mode
= Check_Semantics
then
1000 Back_End_Mode
:= Declarations_Only
;
1002 -- All remaining cases are cases in which the user requested that code
1003 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
1004 -- can in fact satisfy this request.
1006 -- Cannot generate code if someone has turned off code generation for
1007 -- any reason at all. We will try to figure out a reason below.
1009 elsif Operating_Mode
/= Generate_Code
then
1010 Back_End_Mode
:= Skip
;
1012 -- We can generate code for a subprogram body unless there were missing
1013 -- subunits. Note that we always generate code for all generic units (a
1014 -- change from some previous versions of GNAT).
1016 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
1017 Back_End_Mode
:= Generate_Object
;
1019 -- We can generate code for a package body unless there are subunits
1020 -- missing (note that we always generate code for generic units, which
1021 -- is a change from some earlier versions of GNAT).
1023 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
1024 Back_End_Mode
:= Generate_Object
;
1026 -- We can generate code for a package declaration or a subprogram
1027 -- declaration only if it does not required a body.
1029 elsif Nkind_In
(Main_Kind
,
1030 N_Package_Declaration
,
1031 N_Subprogram_Declaration
)
1033 (not Body_Required
(Main_Unit_Node
)
1035 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
1037 Back_End_Mode
:= Generate_Object
;
1039 -- We can generate code for a generic package declaration of a generic
1040 -- subprogram declaration only if does not require a body.
1042 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
1043 N_Generic_Subprogram_Declaration
)
1044 and then not Body_Required
(Main_Unit_Node
)
1046 Back_End_Mode
:= Generate_Object
;
1048 -- Compilation units that are renamings do not require bodies, so we can
1049 -- generate code for them.
1051 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
1052 N_Subprogram_Renaming_Declaration
)
1054 Back_End_Mode
:= Generate_Object
;
1056 -- Compilation units that are generic renamings do not require bodies
1057 -- so we can generate code for them.
1059 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
1060 Back_End_Mode
:= Generate_Object
;
1062 -- It is not an error to analyze in CodePeer mode a spec which requires
1063 -- a body, in order to generate SCIL for this spec.
1065 elsif CodePeer_Mode
then
1066 Back_End_Mode
:= Generate_Object
;
1068 -- It is not an error to analyze in Alfa mode a spec which requires a
1069 -- body, when the body is not available. During frame condition
1070 -- generation, the corresponding ALI file is generated. During
1071 -- translation to Why, Why code is generated for the spec.
1073 elsif Alfa_Mode
then
1074 if Frame_Condition_Mode
then
1075 Back_End_Mode
:= Declarations_Only
;
1077 Back_End_Mode
:= Generate_Object
;
1080 -- In all other cases (specs which have bodies, generics, and bodies
1081 -- where subunits are missing), we cannot generate code and we generate
1082 -- a warning message. Note that generic instantiations are gone at this
1083 -- stage since they have been replaced by their instances.
1086 Back_End_Mode
:= Skip
;
1089 -- At this stage Back_End_Mode is set to indicate if the backend should
1090 -- be called to generate code. If it is Skip, then code generation has
1091 -- been turned off, even though code was requested by the original
1092 -- command. This is not an error from the user point of view, but it is
1093 -- an error from the point of view of the gcc driver, so we must exit
1094 -- with an error status.
1096 -- We generate an informative message (from the gcc point of view, it
1097 -- is an error message, but from the users point of view this is not an
1098 -- error, just a consequence of compiling something that cannot
1101 if Back_End_Mode
= Skip
then
1103 Write_Str
("cannot generate code for ");
1104 Write_Str
("file ");
1105 Write_Name
(Unit_File_Name
(Main_Unit
));
1107 if Subunits_Missing
then
1108 Write_Str
(" (missing subunits)");
1111 -- Force generation of ALI file, for backward compatibility
1113 Opt
.Force_ALI_Tree_File
:= True;
1115 elsif Main_Kind
= N_Subunit
then
1116 Write_Str
(" (subunit)");
1119 -- Force generation of ALI file, for backward compatibility
1121 Opt
.Force_ALI_Tree_File
:= True;
1123 elsif Main_Kind
= N_Subprogram_Declaration
then
1124 Write_Str
(" (subprogram spec)");
1127 -- Generic package body in GNAT implementation mode
1129 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
1130 Write_Str
(" (predefined generic)");
1133 -- Force generation of ALI file, for backward compatibility
1135 Opt
.Force_ALI_Tree_File
:= True;
1137 -- Only other case is a package spec
1140 Write_Str
(" (package spec)");
1144 Set_Standard_Output
;
1146 Sem_Ch13
.Validate_Unchecked_Conversions
;
1147 Sem_Ch13
.Validate_Address_Clauses
;
1148 Sem_Ch13
.Validate_Independence
;
1149 Errout
.Finalize
(Last_Call
=> True);
1150 Errout
.Output_Messages
;
1154 -- Generate ALI file if specially requested, or for missing subunits,
1155 -- subunits or predefined generic.
1157 if Opt
.Force_ALI_Tree_File
then
1158 Write_ALI
(Object
=> False);
1164 -- Exit program with error indication, to kill object file
1166 Exit_Program
(E_No_Code
);
1169 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1170 -- as indicated by Back_Annotate_Rep_Info being set to True.
1172 -- We don't call for annotations on a subunit, because to process those
1173 -- the back-end requires that the parent(s) be properly compiled.
1175 -- Annotation is suppressed for targets where front-end layout is
1176 -- enabled, because the front end determines representations.
1178 -- Annotation is also suppressed in the case of compiling for a VM,
1179 -- since representations are largely symbolic there.
1181 if Back_End_Mode
= Declarations_Only
1182 and then (not (Back_Annotate_Rep_Info
or Generate_SCIL
)
1183 or else Main_Kind
= N_Subunit
1184 or else Targparm
.Frontend_Layout_On_Target
1185 or else Targparm
.VM_Target
/= No_VM
)
1187 Sem_Ch13
.Validate_Unchecked_Conversions
;
1188 Sem_Ch13
.Validate_Address_Clauses
;
1189 Sem_Ch13
.Validate_Independence
;
1190 Errout
.Finalize
(Last_Call
=> True);
1191 Errout
.Output_Messages
;
1192 Write_ALI
(Object
=> False);
1200 -- Ensure that we properly register a dependency on system.ads, since
1201 -- even if we do not semantically depend on this, Targparm has read
1202 -- system parameters from the system.ads file.
1204 Lib
.Writ
.Ensure_System_Dependency
;
1206 -- Add dependencies, if any, on preprocessing data file and on
1207 -- preprocessing definition file(s).
1209 Prepcomp
.Add_Dependencies
;
1211 -- Back end needs to explicitly unlock tables it needs to touch
1224 -- Here we call the back end to generate the output code
1226 Generating_Code
:= True;
1227 Back_End
.Call_Back_End
(Back_End_Mode
);
1229 -- Once the backend is complete, we unlock the names table. This call
1230 -- allows a few extra entries, needed for example for the file name for
1231 -- the library file output.
1235 -- Generate the call-graph output of dispatching calls
1237 Exp_CG
.Generate_CG_Output
;
1239 -- Validate unchecked conversions (using the values for size and
1240 -- alignment annotated by the backend where possible).
1242 Sem_Ch13
.Validate_Unchecked_Conversions
;
1244 -- Validate address clauses (again using alignment values annotated
1245 -- by the backend where possible).
1247 Sem_Ch13
.Validate_Address_Clauses
;
1249 -- Validate independence pragmas (again using values annotated by
1250 -- the back end for component layout etc.)
1252 Sem_Ch13
.Validate_Independence
;
1254 -- Now we complete output of errors, rep info and the tree info. These
1255 -- are delayed till now, since it is perfectly possible for gigi to
1256 -- generate errors, modify the tree (in particular by setting flags
1257 -- indicating that elaboration is required, and also to back annotate
1258 -- representation information for List_Rep_Info.
1260 Errout
.Finalize
(Last_Call
=> True);
1261 Errout
.Output_Messages
;
1265 -- Only write the library if the backend did not generate any error
1266 -- messages. Otherwise signal errors to the driver program so that
1267 -- there will be no attempt to generate an object file.
1269 if Compilation_Errors
then
1271 Exit_Program
(E_Errors
);
1274 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
));
1276 if not Compilation_Errors
then
1278 -- In case of ada backends, we need to make sure that the generated
1279 -- object file has a timestamp greater than the ALI file. We do this
1280 -- to make gnatmake happy when checking the ALI and obj timestamps,
1281 -- where it expects the object file being written after the ali file.
1283 -- Gnatmake's assumption is true for gcc platforms where the gcc
1284 -- wrapper needs to call the assembler after calling gnat1, but is
1285 -- not true for ada backends, where the object files are created
1286 -- directly by gnat1 (so are created before the ali file).
1288 Back_End
.Gen_Or_Update_Object_File
;
1291 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1292 -- Write_ALI may in fact result in further tree decoration from the
1293 -- original tree file. Note that we dump the tree just before generating
1294 -- it, so that the dump will exactly reflect what is written out.
1299 -- Finalize name table and we are all done
1304 -- Handle fatal internal compiler errors
1306 when Rtsfind
.RE_Not_Available
=>
1307 Comperr
.Compiler_Abort
("RE_Not_Available");
1309 when System
.Assertions
.Assert_Failure
=>
1310 Comperr
.Compiler_Abort
("Assert_Failure");
1312 when Constraint_Error
=>
1313 Comperr
.Compiler_Abort
("Constraint_Error");
1315 when Program_Error
=>
1316 Comperr
.Compiler_Abort
("Program_Error");
1318 when Storage_Error
=>
1320 -- Assume this is a bug. If it is real, the message will in any case
1321 -- say Storage_Error, giving a strong hint!
1323 Comperr
.Compiler_Abort
("Storage_Error");
1329 -- The outer exception handles an unrecoverable error
1332 when Unrecoverable_Error
=>
1333 Errout
.Finalize
(Last_Call
=> True);
1334 Errout
.Output_Messages
;
1337 Write_Str
("compilation abandoned");
1340 Set_Standard_Output
;
1343 Exit_Program
(E_Errors
);