1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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
;
30 with Csets
; use Csets
;
31 with Debug
; use Debug
;
33 with Errout
; use Errout
;
36 with Fname
; use Fname
;
37 with Fname
.UF
; use Fname
.UF
;
39 with Gnatvsn
; use Gnatvsn
;
42 with Lib
.Writ
; use Lib
.Writ
;
44 with Namet
; use Namet
;
47 with Osint
; use Osint
;
48 with Output
; use Output
;
51 with Repinfo
; use Repinfo
;
53 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
;
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
;
90 Main_Unit_Node
: Node_Id
;
91 -- Compilation unit node for main unit
93 Main_Kind
: Node_Kind
;
94 -- Kind of main compilation unit node
96 Back_End_Mode
: Back_End
.Back_End_Mode_Type
;
97 -- Record back end mode
99 procedure Adjust_Global_Switches
;
100 -- There are various interactions between front end switch settings,
101 -- including debug switch settings and target dependent parameters.
102 -- This procedure takes care of properly handling these interactions.
103 -- We do it after scanning out all the switches, so that we are not
104 -- depending on the order in which switches appear.
106 procedure Check_Bad_Body
;
107 -- Called to check if the unit we are compiling has a bad body
109 procedure Check_Rep_Info
;
110 -- Called when we are not generating code, to check if -gnatR was requested
111 -- and if so, explain that we will not be honoring the request.
113 procedure Post_Compilation_Validation_Checks
;
114 -- This procedure performs various validation checks that have to be left
115 -- to the end of the compilation process, after generating code but before
116 -- issuing error messages. In particular, these checks generally require
117 -- the information provided by the back end in back annotation of declared
118 -- entities (e.g. actual size and alignment values chosen by the back end).
120 ----------------------------
121 -- Adjust_Global_Switches --
122 ----------------------------
124 procedure Adjust_Global_Switches
is
126 -- -gnatd.M enables Relaxed_RM_Semantics
128 if Debug_Flag_Dot_MM
then
129 Relaxed_RM_Semantics
:= True;
132 -- -gnatd.V or -gnatd.u enables special C expansion mode
134 if Debug_Flag_Dot_VV
or Debug_Flag_Dot_U
then
135 Modify_Tree_For_C
:= True;
138 -- -gnatd.E sets Error_To_Warning mode, causing selected error messages
139 -- to be treated as warnings instead of errors.
141 if Debug_Flag_Dot_EE
then
142 Error_To_Warning
:= True;
145 -- Disable CodePeer_Mode in Check_Syntax, since we need front-end
148 if Operating_Mode
= Check_Syntax
then
149 CodePeer_Mode
:= False;
152 -- Set ASIS mode if -gnatt and -gnatc are set
154 if Operating_Mode
= Check_Semantics
and then Tree_Output
then
157 -- Turn off inlining in ASIS mode, since ASIS cannot handle the extra
158 -- information in the trees caused by inlining being active.
160 -- More specifically, the tree seems to be malformed from the ASIS
161 -- point of view if -gnatc and -gnatn appear together???
163 Inline_Active
:= False;
165 -- Turn off SCIL generation and CodePeer mode in semantics mode,
166 -- since SCIL requires front-end expansion.
168 Generate_SCIL
:= False;
169 CodePeer_Mode
:= False;
172 -- SCIL mode needs to disable front-end inlining since the generated
173 -- trees (in particular order and consistency between specs compiled
174 -- as part of a main unit or as part of a with-clause) are causing
177 if Generate_SCIL
then
178 Front_End_Inlining
:= False;
181 -- Tune settings for optimal SCIL generation in CodePeer mode
183 if CodePeer_Mode
then
185 -- Turn off inlining, confuses CodePeer output and gains nothing
187 Front_End_Inlining
:= False;
188 Inline_Active
:= False;
190 -- Disable front-end optimizations, to keep the tree as close to the
191 -- source code as possible, and also to avoid inconsistencies between
192 -- trees when using different optimization switches.
194 Optimization_Level
:= 0;
196 -- Enable some restrictions systematically to simplify the generated
197 -- code (and ease analysis). Note that restriction checks are also
198 -- disabled in CodePeer mode, see Restrict.Check_Restriction, and
199 -- user specified Restrictions pragmas are ignored, see
200 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
202 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
203 Restrict
.Restrictions
.Set
(No_Task_Hierarchy
) := True;
204 Restrict
.Restrictions
.Set
(No_Abort_Statements
) := True;
205 Restrict
.Restrictions
.Set
(Max_Asynchronous_Select_Nesting
) := True;
206 Restrict
.Restrictions
.Value
(Max_Asynchronous_Select_Nesting
) := 0;
208 -- Suppress division by zero and access checks since they are handled
209 -- implicitly by CodePeer.
211 -- Turn off dynamic elaboration checks: generates inconsistencies in
212 -- trees between specs compiled as part of a main unit or as part of
215 -- Turn off alignment checks: these cannot be proved statically by
216 -- CodePeer and generate false positives.
218 -- Enable all other language checks
220 Suppress_Options
.Suppress
:=
221 (Access_Check
=> True,
222 Alignment_Check
=> True,
223 Division_Check
=> True,
224 Elaboration_Check
=> True,
227 Dynamic_Elaboration_Checks
:= False;
229 -- Set STRICT mode for overflow checks if not set explicitly. This
230 -- prevents suppressing of overflow checks by default, in code down
233 if Suppress_Options
.Overflow_Mode_General
= Not_Set
then
234 Suppress_Options
.Overflow_Mode_General
:= Strict
;
235 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
238 -- CodePeer handles division and overflow checks directly, based on
239 -- the marks set by the frontend, hence no special expansion should
240 -- be performed in the frontend for division and overflow checks.
242 Backend_Divide_Checks_On_Target
:= True;
243 Backend_Overflow_Checks_On_Target
:= True;
245 -- Kill debug of generated code, since it messes up sloc values
247 Debug_Generated_Code
:= False;
249 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
250 -- Do we really need to spend time generating xref in CodePeer
251 -- mode??? Consider setting Xref_Active to False.
255 -- Polling mode forced off, since it generates confusing junk
257 Polling_Required
:= False;
259 -- Set operating mode to Generate_Code to benefit from full front-end
260 -- expansion (e.g. generics).
262 Operating_Mode
:= Generate_Code
;
264 -- We need SCIL generation of course
266 Generate_SCIL
:= True;
268 -- Enable assertions, since they give CodePeer valuable extra info
270 Assertions_Enabled
:= True;
272 -- Disable all simple value propagation. This is an optimization
273 -- which is valuable for code optimization, and also for generation
274 -- of compiler warnings, but these are being turned off by default,
275 -- and CodePeer generates better messages (referencing original
276 -- variables) this way.
278 Debug_Flag_MM
:= True;
280 -- Set normal RM validity checking, and checking of IN OUT parameters
281 -- (this might give CodePeer more useful checks to analyze, to be
282 -- confirmed???). All other validity checking is turned off, since
283 -- this can generate very complex trees that only confuse CodePeer
284 -- and do not bring enough useful info.
286 Reset_Validity_Check_Options
;
287 Validity_Check_Default
:= True;
288 Validity_Check_In_Out_Params
:= True;
289 Validity_Check_In_Params
:= True;
291 -- Turn off style check options since we are not interested in any
292 -- front-end warnings when we are getting CodePeer output.
294 Reset_Style_Check_Options
;
296 -- Always perform semantics and generate ali files in CodePeer mode,
297 -- so that a gnatmake -c -k will proceed further when possible.
299 Force_ALI_Tree_File
:= True;
300 Try_Semantics
:= True;
302 -- Make the Ada front-end more liberal so that the compiler will
303 -- allow illegal code that is allowed by other compilers. CodePeer
304 -- is in the business of finding problems, not enforcing rules.
305 -- This is useful when using CodePeer mode with other compilers.
307 Relaxed_RM_Semantics
:= True;
310 -- Enable some individual switches that are implied by relaxed RM
313 if Relaxed_RM_Semantics
then
314 Opt
.Allow_Integer_Address
:= True;
315 Overriding_Renamings
:= True;
316 Treat_Categorization_Errors_As_Warnings
:= True;
319 -- Enable GNATprove_Mode when using -gnatd.F switch
321 if Debug_Flag_Dot_FF
then
322 GNATprove_Mode
:= True;
325 -- GNATprove_Mode is also activated by default in the gnat2why
328 if GNATprove_Mode
then
330 -- Turn off inlining, which would confuse formal verification output
333 Front_End_Inlining
:= False;
334 Inline_Active
:= False;
336 -- Issue warnings for failure to inline subprograms, as otherwise
337 -- expected in GNATprove mode for the local subprograms without
340 Ineffective_Inline_Warnings
:= True;
342 -- Disable front-end optimizations, to keep the tree as close to the
343 -- source code as possible, and also to avoid inconsistencies between
344 -- trees when using different optimization switches.
346 Optimization_Level
:= 0;
348 -- Enable some restrictions systematically to simplify the generated
349 -- code (and ease analysis). Note that restriction checks are also
350 -- disabled in SPARK mode, see Restrict.Check_Restriction, and user
351 -- specified Restrictions pragmas are ignored, see
352 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
354 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
356 -- Note: at this point we used to suppress various checks, but that
357 -- is not what we want. We need the semantic processing for these
358 -- checks (which will set flags like Do_Overflow_Check, showing the
359 -- points at which potential checks are required semantically). We
360 -- don't want the expansion associated with these checks, but that
361 -- happens anyway because this expansion is simply not done in the
362 -- SPARK version of the expander.
364 -- Turn off dynamic elaboration checks: generates inconsistencies in
365 -- trees between specs compiled as part of a main unit or as part of
368 -- Comment is incomplete, SPARK semantics rely on static mode no???
370 Dynamic_Elaboration_Checks
:= False;
372 -- Detect overflow on unconstrained floating-point types, such as
373 -- the predefined types Float, Long_Float and Long_Long_Float from
376 Check_Float_Overflow
:= True;
378 -- Set STRICT mode for overflow checks if not set explicitly. This
379 -- prevents suppressing of overflow checks by default, in code down
382 if Suppress_Options
.Overflow_Mode_General
= Not_Set
then
383 Suppress_Options
.Overflow_Mode_General
:= Strict
;
384 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
387 -- Kill debug of generated code, since it messes up sloc values
389 Debug_Generated_Code
:= False;
391 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
392 -- as it is needed for computing effects of subprograms in the formal
393 -- verification backend.
397 -- Polling mode forced off, since it generates confusing junk
399 Polling_Required
:= False;
401 -- Set operating mode to Check_Semantics, but a light front-end
402 -- expansion is still performed.
404 Operating_Mode
:= Check_Semantics
;
406 -- Enable assertions, since they give valuable extra information for
407 -- formal verification.
409 Assertions_Enabled
:= True;
411 -- Disable validity checks, since it generates code raising
412 -- exceptions for invalid data, which confuses GNATprove. Invalid
413 -- data is directly detected by GNATprove's flow analysis.
415 Validity_Checks_On
:= False;
417 -- Turn off style check options since we are not interested in any
418 -- front-end warnings when we are getting SPARK output.
420 Reset_Style_Check_Options
;
422 -- Suppress the generation of name tables for enumerations, which are
423 -- not needed for formal verification, and fall outside the SPARK
424 -- subset (use of pointers).
426 Global_Discard_Names
:= True;
428 -- Suppress the expansion of tagged types and dispatching calls,
429 -- which lead to the generation of non-SPARK code (use of pointers),
430 -- which is more complex to formally verify than the original source.
432 Tagged_Type_Expansion
:= False;
435 -- Set Configurable_Run_Time mode if system.ads flag set or if the
436 -- special debug flag -gnatdY is set.
438 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
439 Configurable_Run_Time_Mode
:= True;
442 -- Set -gnatR3m mode if debug flag A set
444 if Debug_Flag_AA
then
445 Back_Annotate_Rep_Info
:= True;
446 List_Representation_Info
:= 1;
447 List_Representation_Info_Mechanisms
:= True;
450 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
452 if Debug_Flag_Dot_A
then
453 Ttypes
.Target_Strict_Alignment
:= True;
456 -- Increase size of allocated entities if debug flag -gnatd.N is set
458 if Debug_Flag_Dot_NN
then
459 Atree
.Num_Extension_Nodes
:= Atree
.Num_Extension_Nodes
+ 1;
462 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
463 -- is enabled. The front end's layout phase currently treats types that
464 -- have discriminant-dependent arrays as not being static even when a
465 -- discriminant constraint on the type is static, and this leads to
466 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
468 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
469 Static_Dispatch_Tables
:= False;
472 -- Flip endian mode if -gnatd8 set
475 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
478 -- Temporarily set True_VMS_Target to OpenVMS_On_Target. This is just
479 -- temporary, we no longer deal with the debug flag -gnatdm here.
481 Opt
.True_VMS_Target
:= Targparm
.OpenVMS_On_Target
;
483 -- Activate front end layout if debug flag -gnatdF is set
485 if Debug_Flag_FF
then
486 Targparm
.Frontend_Layout_On_Target
:= True;
489 -- Set and check exception mechanism
491 if Targparm
.ZCX_By_Default_On_Target
then
492 Exception_Mechanism
:= Back_End_Exceptions
;
495 -- Set proper status for overflow check mechanism
497 -- If already set (by -gnato or above in SPARK or CodePeer mode) then we
498 -- have nothing to do.
500 if Opt
.Suppress_Options
.Overflow_Mode_General
/= Not_Set
then
503 -- Otherwise set overflow mode defaults
506 -- Overflow checks are on by default (Suppress set False) except in
507 -- GNAT_Mode, where we want them off by default (we are not ready to
508 -- enable overflow checks in the compiler yet, for one thing the case
509 -- of 64-bit checks needs System.Arith_64 which is not a compiler
510 -- unit and it is a pain to try to include it in the compiler.
512 Suppress_Options
.Suppress
(Overflow_Check
) := GNAT_Mode
;
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 back end can handle limited types, and
555 -- guarantee that no incorrect copies are made (e.g. in the context
556 -- of an if or case expression).
558 -- Debug flag -gnatd.L decisively sets usage on
560 if Debug_Flag_Dot_LL
then
561 Back_End_Handles_Limited_Types
:= True;
563 -- If no debug flag, usage off for AAMP, VM, SCIL cases
566 or else VM_Target
/= No_VM
567 or else Generate_SCIL
569 Back_End_Handles_Limited_Types
:= False;
571 -- Otherwise normal gcc back end, for now still turn flag off by
572 -- default, since there are unresolved problems in the front end.
575 Back_End_Handles_Limited_Types
:= False;
578 -- If the inlining level has not been set by the user, compute it from
579 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
581 if Inline_Level
= 0 then
582 if Optimization_Level
< 3 then
589 -- Set back end inlining indication
593 -- No back end inlining if inlining is suppressed
595 not Suppress_All_Inlining
597 -- No back end inlining available for VM targets
599 and then VM_Target
= No_VM
601 -- No back end inlining available on AAMP
603 and then not AAMP_On_Target
605 -- No back end inlining in GNATprove mode, since it just confuses
606 -- the formal verification process.
608 and then not GNATprove_Mode
610 -- No back end inlining if front end inlining explicitly enabled?
612 and then not Front_End_Inlining
614 -- For now, we only enable back end inlining if debug flag .z is set
616 and then Debug_Flag_Dot_Z
;
618 -- Output warning if -gnateE specified and cannot be supported
620 if Exception_Extra_Info
621 and then Restrict
.No_Exception_Handlers_Set
625 ("warning: extra exception information (-gnateE) was specified");
628 ("warning: this capability is not available in this configuration");
633 -- Finally capture adjusted value of Suppress_Options as the initial
634 -- value for Scope_Suppress, which will be modified as we move from
635 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
637 Sem
.Scope_Suppress
:= Opt
.Suppress_Options
;
638 end Adjust_Global_Switches
;
644 procedure Check_Bad_Body
is
645 Sname
: Unit_Name_Type
;
646 Src_Ind
: Source_File_Index
;
647 Fname
: File_Name_Type
;
649 procedure Bad_Body_Error
(Msg
: String);
650 -- Issue message for bad body found
656 procedure Bad_Body_Error
(Msg
: String) is
658 Error_Msg_N
(Msg
, Main_Unit_Node
);
659 Error_Msg_File_1
:= Fname
;
660 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
663 -- Start of processing for Check_Bad_Body
666 -- Nothing to do if we are only checking syntax, because we don't know
667 -- enough to know if we require or forbid a body in this case.
669 if Operating_Mode
= Check_Syntax
then
673 -- Check for body not allowed
675 if (Main_Kind
= N_Package_Declaration
676 and then not Body_Required
(Main_Unit_Node
))
677 or else (Main_Kind
= N_Generic_Package_Declaration
678 and then not Body_Required
(Main_Unit_Node
))
679 or else Main_Kind
= N_Package_Renaming_Declaration
680 or else Main_Kind
= N_Subprogram_Renaming_Declaration
681 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
682 in N_Generic_Instantiation
684 Sname
:= Unit_Name
(Main_Unit
);
686 -- If we do not already have a body name, then get the body name
688 if not Is_Body_Name
(Sname
) then
689 Sname
:= Get_Body_Name
(Sname
);
692 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
693 Src_Ind
:= Load_Source_File
(Fname
);
695 -- Case where body is present and it is not a subunit. Exclude the
696 -- subunit case, because it has nothing to do with the package we are
697 -- compiling. It is illegal for a child unit and a subunit with the
698 -- same expanded name (RM 10.2(9)) to appear together in a partition,
699 -- but there is nothing to stop a compilation environment from having
700 -- both, and the test here simply allows that. If there is an attempt
701 -- to include both in a partition, this is diagnosed at bind time. In
702 -- Ada 83 mode this is not a warning case.
704 -- Note that in general we do not give the message if the file in
705 -- question does not look like a body. This includes weird cases,
706 -- but in particular means that if the file is just a No_Body pragma,
707 -- then we won't give the message (that's the whole point of this
708 -- pragma, to be used this way and to cause the body file to be
709 -- ignored in this context).
711 if Src_Ind
/= No_Source_File
712 and then Source_File_Is_Body
(Src_Ind
)
714 Errout
.Finalize
(Last_Call
=> False);
716 Error_Msg_Unit_1
:= Sname
;
718 -- Ada 83 case of a package body being ignored. This is not an
719 -- error as far as the Ada 83 RM is concerned, but it is almost
720 -- certainly not what is wanted so output a warning. Give this
721 -- message only if there were no errors, since otherwise it may
722 -- be incorrect (we may have misinterpreted a junk spec as not
723 -- needing a body when it really does).
725 if Main_Kind
= N_Package_Declaration
726 and then Ada_Version
= Ada_83
727 and then Operating_Mode
= Generate_Code
728 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
729 and then not Compilation_Errors
732 ("package $$ does not require a body??", Main_Unit_Node
);
733 Error_Msg_File_1
:= Fname
;
734 Error_Msg_N
("body in file{ will be ignored??", Main_Unit_Node
);
736 -- Ada 95 cases of a body file present when no body is
737 -- permitted. This we consider to be an error.
740 -- For generic instantiations, we never allow a body
742 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
))) in
743 N_Generic_Instantiation
746 ("generic instantiation for $$ does not allow a body");
748 -- A library unit that is a renaming never allows a body
750 elsif Main_Kind
in N_Renaming_Declaration
then
752 ("renaming declaration for $$ does not allow a body!");
754 -- Remaining cases are packages and generic packages. Here
755 -- we only do the test if there are no previous errors,
756 -- because if there are errors, they may lead us to
757 -- incorrectly believe that a package does not allow a
758 -- body when in fact it does.
760 elsif not Compilation_Errors
then
761 if Main_Kind
= N_Package_Declaration
then
763 ("package $$ does not allow a body!");
765 elsif Main_Kind
= N_Generic_Package_Declaration
then
767 ("generic package $$ does not allow a body!");
780 procedure Check_Rep_Info
is
782 if List_Representation_Info
/= 0
783 or else List_Representation_Info_Mechanisms
788 ("cannot generate representation information, no code generated");
795 ----------------------------------------
796 -- Post_Compilation_Validation_Checks --
797 ----------------------------------------
799 procedure Post_Compilation_Validation_Checks
is
801 -- Validate alignment check warnings. In some cases we generate warnings
802 -- about possible alignment errors because we don't know the alignment
803 -- that will be chosen by the back end. This routine is in charge of
804 -- getting rid of those warnings if we can tell they are not needed.
806 Checks
.Validate_Alignment_Check_Warnings
;
808 -- Validate unchecked conversions (using the values for size and
809 -- alignment annotated by the backend where possible).
811 Sem_Ch13
.Validate_Unchecked_Conversions
;
813 -- Validate address clauses (again using alignment values annotated
814 -- by the backend where possible).
816 Sem_Ch13
.Validate_Address_Clauses
;
818 -- Validate independence pragmas (again using values annotated by
819 -- the back end for component layout etc.)
821 Sem_Ch13
.Validate_Independence
;
822 end Post_Compilation_Validation_Checks
;
824 -- Start of processing for Gnat1drv
827 -- This inner block is set up to catch assertion errors and constraint
828 -- errors. Since the code for handling these errors can cause another
829 -- exception to be raised (namely Unrecoverable_Error), we need two
830 -- nested blocks, so that the outer one handles unrecoverable error.
833 -- Initialize all packages. For the most part, these initialization
834 -- calls can be made in any order. Exceptions are as follows:
836 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
837 -- because it initializes a table filled by Scan_Compiler_Arguments.
843 Scan_Compiler_Arguments
;
844 Osint
.Add_Default_Search_Dirs
;
865 Sem_Type
.Init_Interp_Tables
;
867 -- Capture compilation date and time
869 Opt
.Compilation_Time
:= System
.OS_Lib
.Current_Time_String
;
871 -- Acquire target parameters from system.ads (source of package System)
873 Targparm_Acquire
: declare
876 S
: Source_File_Index
;
880 Name_Buffer
(1 .. 10) := "system.ads";
883 S
:= Load_Source_File
(N
);
885 if S
= No_Source_File
then
887 ("fatal error, run-time library not installed correctly");
888 Write_Line
("cannot locate file system.ads");
889 raise Unrecoverable_Error
;
891 -- Remember source index of system.ads (which was read successfully)
894 System_Source_File_Index
:= S
;
897 Targparm
.Get_Target_Parameters
898 (System_Text
=> Source_Text
(S
),
899 Source_First
=> Source_First
(S
),
900 Source_Last
=> Source_Last
(S
),
901 Make_Id
=> Tbuild
.Make_Id
'Access,
902 Make_SC
=> Tbuild
.Make_SC
'Access,
903 Set_RND
=> Tbuild
.Set_RND
'Access);
905 -- Acquire configuration pragma information from Targparm
907 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
908 end Targparm_Acquire
;
910 -- Perform various adjustments and settings of global switches
912 Adjust_Global_Switches
;
914 -- Output copyright notice if full list mode unless we have a list
915 -- file, in which case we defer this so that it is output in the file
917 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
918 and then not Debug_Flag_7
922 Write_Str
(Gnat_Version_String
);
924 Write_Str
("Copyright 1992-" & Current_Year
925 & ", Free Software Foundation, Inc.");
929 -- Check we do not have more than one source file, this happens only in
930 -- the case where the driver is called directly, it cannot happen when
931 -- gnat1 is invoked from gcc in the normal case.
933 if Osint
.Number_Of_Files
/= 1 then
936 Osint
.Fail
("you must provide one source file");
938 elsif Usage_Requested
then
942 -- Generate target dependent output file if requested
944 if Target_Dependent_Info_Write_Name
/= null then
945 Set_Targ
.Write_Target_Dependent_Values
;
948 -- Call the front end
950 Original_Operating_Mode
:= Operating_Mode
;
953 -- Exit with errors if the main source could not be parsed.
955 if Sinput
.Main_Source_File
= No_Source_File
then
956 Errout
.Finalize
(Last_Call
=> True);
957 Errout
.Output_Messages
;
958 Exit_Program
(E_Errors
);
961 Main_Unit_Node
:= Cunit
(Main_Unit
);
962 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
965 -- In CodePeer mode we always delete old SCIL files before regenerating
966 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
967 -- files generated by CodePeer itself.
969 if CodePeer_Mode
then
970 Comperr
.Delete_SCIL_Files
;
973 -- Exit if compilation errors detected
975 Errout
.Finalize
(Last_Call
=> False);
977 if Compilation_Errors
then
979 Post_Compilation_Validation_Checks
;
980 Errout
.Output_Messages
;
983 -- Generate ALI file if specially requested
985 if Opt
.Force_ALI_Tree_File
then
986 Write_ALI
(Object
=> False);
990 Errout
.Finalize
(Last_Call
=> True);
991 Exit_Program
(E_Errors
);
994 -- Set Generate_Code on main unit and its spec. We do this even if are
995 -- not generating code, since Lib-Writ uses this to determine which
996 -- units get written in the ali file.
998 Set_Generate_Code
(Main_Unit
);
1000 -- If we have a corresponding spec, and it comes from source or it is
1001 -- not a generated spec for a child subprogram body, then we need object
1002 -- code for the spec unit as well.
1004 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
1005 and then not Acts_As_Spec
(Main_Unit_Node
)
1007 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
1008 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
1013 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
1017 -- Case of no code required to be generated, exit indicating no error
1019 if Original_Operating_Mode
= Check_Syntax
then
1021 Errout
.Finalize
(Last_Call
=> True);
1022 Errout
.Output_Messages
;
1027 -- Use a goto instead of calling Exit_Program so that finalization
1030 goto End_Of_Program
;
1032 elsif Original_Operating_Mode
= Check_Semantics
then
1033 Back_End_Mode
:= Declarations_Only
;
1035 -- All remaining cases are cases in which the user requested that code
1036 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
1037 -- can in fact satisfy this request.
1039 -- Cannot generate code if someone has turned off code generation for
1040 -- any reason at all. We will try to figure out a reason below.
1042 elsif Operating_Mode
/= Generate_Code
then
1043 Back_End_Mode
:= Skip
;
1045 -- We can generate code for a subprogram body unless there were missing
1046 -- subunits. Note that we always generate code for all generic units (a
1047 -- change from some previous versions of GNAT).
1049 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
1050 Back_End_Mode
:= Generate_Object
;
1052 -- We can generate code for a package body unless there are subunits
1053 -- missing (note that we always generate code for generic units, which
1054 -- is a change from some earlier versions of GNAT).
1056 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
1057 Back_End_Mode
:= Generate_Object
;
1059 -- We can generate code for a package declaration or a subprogram
1060 -- declaration only if it does not required a body.
1062 elsif Nkind_In
(Main_Kind
,
1063 N_Package_Declaration
,
1064 N_Subprogram_Declaration
)
1066 (not Body_Required
(Main_Unit_Node
)
1068 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
1070 Back_End_Mode
:= Generate_Object
;
1072 -- We can generate code for a generic package declaration of a generic
1073 -- subprogram declaration only if does not require a body.
1075 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
1076 N_Generic_Subprogram_Declaration
)
1077 and then not Body_Required
(Main_Unit_Node
)
1079 Back_End_Mode
:= Generate_Object
;
1081 -- Compilation units that are renamings do not require bodies, so we can
1082 -- generate code for them.
1084 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
1085 N_Subprogram_Renaming_Declaration
)
1087 Back_End_Mode
:= Generate_Object
;
1089 -- Compilation units that are generic renamings do not require bodies
1090 -- so we can generate code for them.
1092 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
1093 Back_End_Mode
:= Generate_Object
;
1095 -- It is not an error to analyze in CodePeer mode a spec which requires
1096 -- a body, in order to generate SCIL for this spec.
1098 elsif CodePeer_Mode
then
1099 Back_End_Mode
:= Generate_Object
;
1101 -- It is not an error to analyze in GNATprove mode a spec which requires
1102 -- a body, when the body is not available. During frame condition
1103 -- generation, the corresponding ALI file is generated. During
1104 -- analysis, the spec is analyzed.
1106 elsif GNATprove_Mode
then
1107 Back_End_Mode
:= Declarations_Only
;
1109 -- In all other cases (specs which have bodies, generics, and bodies
1110 -- where subunits are missing), we cannot generate code and we generate
1111 -- a warning message. Note that generic instantiations are gone at this
1112 -- stage since they have been replaced by their instances.
1115 Back_End_Mode
:= Skip
;
1118 -- At this stage Back_End_Mode is set to indicate if the backend should
1119 -- be called to generate code. If it is Skip, then code generation has
1120 -- been turned off, even though code was requested by the original
1121 -- command. This is not an error from the user point of view, but it is
1122 -- an error from the point of view of the gcc driver, so we must exit
1123 -- with an error status.
1125 -- We generate an informative message (from the gcc point of view, it
1126 -- is an error message, but from the users point of view this is not an
1127 -- error, just a consequence of compiling something that cannot
1130 if Back_End_Mode
= Skip
then
1132 Write_Str
("cannot generate code for ");
1133 Write_Str
("file ");
1134 Write_Name
(Unit_File_Name
(Main_Unit
));
1136 if Subunits_Missing
then
1137 Write_Str
(" (missing subunits)");
1140 -- Force generation of ALI file, for backward compatibility
1142 Opt
.Force_ALI_Tree_File
:= True;
1144 elsif Main_Kind
= N_Subunit
then
1145 Write_Str
(" (subunit)");
1148 -- Force generation of ALI file, for backward compatibility
1150 Opt
.Force_ALI_Tree_File
:= True;
1152 elsif Main_Kind
= N_Subprogram_Declaration
then
1153 Write_Str
(" (subprogram spec)");
1156 -- Generic package body in GNAT implementation mode
1158 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
1159 Write_Str
(" (predefined generic)");
1162 -- Force generation of ALI file, for backward compatibility
1164 Opt
.Force_ALI_Tree_File
:= True;
1166 -- Only other case is a package spec
1169 Write_Str
(" (package spec)");
1173 Set_Standard_Output
;
1175 Post_Compilation_Validation_Checks
;
1176 Errout
.Finalize
(Last_Call
=> True);
1177 Errout
.Output_Messages
;
1181 -- Generate ALI file if specially requested, or for missing subunits,
1182 -- subunits or predefined generic.
1184 if Opt
.Force_ALI_Tree_File
then
1185 Write_ALI
(Object
=> False);
1191 -- Exit program with error indication, to kill object file
1193 Exit_Program
(E_No_Code
);
1196 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1197 -- as indicated by Back_Annotate_Rep_Info being set to True.
1199 -- We don't call for annotations on a subunit, because to process those
1200 -- the back-end requires that the parent(s) be properly compiled.
1202 -- Annotation is suppressed for targets where front-end layout is
1203 -- enabled, because the front end determines representations.
1205 -- Annotation is also suppressed in the case of compiling for a VM,
1206 -- since representations are largely symbolic there.
1208 if Back_End_Mode
= Declarations_Only
1210 (not (Back_Annotate_Rep_Info
or Generate_SCIL
or GNATprove_Mode
)
1211 or else Main_Kind
= N_Subunit
1212 or else Targparm
.Frontend_Layout_On_Target
1213 or else Targparm
.VM_Target
/= No_VM
)
1215 Post_Compilation_Validation_Checks
;
1216 Errout
.Finalize
(Last_Call
=> True);
1217 Errout
.Output_Messages
;
1218 Write_ALI
(Object
=> False);
1226 -- Ensure that we properly register a dependency on system.ads, since
1227 -- even if we do not semantically depend on this, Targparm has read
1228 -- system parameters from the system.ads file.
1230 Lib
.Writ
.Ensure_System_Dependency
;
1232 -- Add dependencies, if any, on preprocessing data file and on
1233 -- preprocessing definition file(s).
1235 Prepcomp
.Add_Dependencies
;
1237 -- Back end needs to explicitly unlock tables it needs to touch
1250 -- Here we call the back end to generate the output code
1252 Generating_Code
:= True;
1253 Back_End
.Call_Back_End
(Back_End_Mode
);
1255 -- Once the backend is complete, we unlock the names table. This call
1256 -- allows a few extra entries, needed for example for the file name for
1257 -- the library file output.
1261 -- Generate the call-graph output of dispatching calls
1263 Exp_CG
.Generate_CG_Output
;
1265 -- Perform post compilation validation checks
1267 Post_Compilation_Validation_Checks
;
1269 -- Now we complete output of errors, rep info and the tree info. These
1270 -- are delayed till now, since it is perfectly possible for gigi to
1271 -- generate errors, modify the tree (in particular by setting flags
1272 -- indicating that elaboration is required, and also to back annotate
1273 -- representation information for List_Rep_Info.
1275 Errout
.Finalize
(Last_Call
=> True);
1276 Errout
.Output_Messages
;
1277 List_Rep_Info
(Ttypes
.Bytes_Big_Endian
);
1278 Inline
.List_Inlining_Info
;
1280 -- Only write the library if the backend did not generate any error
1281 -- messages. Otherwise signal errors to the driver program so that
1282 -- there will be no attempt to generate an object file.
1284 if Compilation_Errors
then
1286 Exit_Program
(E_Errors
);
1289 -- In GNATprove mode, an "object" file is always generated as the
1290 -- result of calling gnat1 or gnat2why, although this is not the
1291 -- same as the object file produced for compilation.
1293 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
1294 or else GNATprove_Mode
));
1296 if not Compilation_Errors
then
1298 -- In case of ada backends, we need to make sure that the generated
1299 -- object file has a timestamp greater than the ALI file. We do this
1300 -- to make gnatmake happy when checking the ALI and obj timestamps,
1301 -- where it expects the object file being written after the ali file.
1303 -- Gnatmake's assumption is true for gcc platforms where the gcc
1304 -- wrapper needs to call the assembler after calling gnat1, but is
1305 -- not true for ada backends, where the object files are created
1306 -- directly by gnat1 (so are created before the ali file).
1308 Back_End
.Gen_Or_Update_Object_File
;
1311 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1312 -- Write_ALI may in fact result in further tree decoration from the
1313 -- original tree file. Note that we dump the tree just before generating
1314 -- it, so that the dump will exactly reflect what is written out.
1319 -- Finalize name table and we are all done
1324 -- Handle fatal internal compiler errors
1326 when Rtsfind
.RE_Not_Available
=>
1327 Comperr
.Compiler_Abort
("RE_Not_Available");
1329 when System
.Assertions
.Assert_Failure
=>
1330 Comperr
.Compiler_Abort
("Assert_Failure");
1332 when Constraint_Error
=>
1333 Comperr
.Compiler_Abort
("Constraint_Error");
1335 when Program_Error
=>
1336 Comperr
.Compiler_Abort
("Program_Error");
1338 when Storage_Error
=>
1340 -- Assume this is a bug. If it is real, the message will in any case
1341 -- say Storage_Error, giving a strong hint.
1343 Comperr
.Compiler_Abort
("Storage_Error");
1349 -- The outer exception handles an unrecoverable error
1352 when Unrecoverable_Error
=>
1353 Errout
.Finalize
(Last_Call
=> True);
1354 Errout
.Output_Messages
;
1357 Write_Str
("compilation abandoned");
1360 Set_Standard_Output
;
1363 Exit_Program
(E_Errors
);