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 and ignore any style check pragmas
292 -- since we are not interested in any front-end warnings when we are
293 -- getting CodePeer output.
295 Reset_Style_Check_Options
;
296 Ignore_Style_Checks_Pragmas
:= True;
298 -- Always perform semantics and generate ali files in CodePeer mode,
299 -- so that a gnatmake -c -k will proceed further when possible.
301 Force_ALI_Tree_File
:= True;
302 Try_Semantics
:= True;
304 -- Make the Ada front-end more liberal so that the compiler will
305 -- allow illegal code that is allowed by other compilers. CodePeer
306 -- is in the business of finding problems, not enforcing rules.
307 -- This is useful when using CodePeer mode with other compilers.
309 Relaxed_RM_Semantics
:= True;
312 -- Enable some individual switches that are implied by relaxed RM
315 if Relaxed_RM_Semantics
then
316 Opt
.Allow_Integer_Address
:= True;
317 Overriding_Renamings
:= True;
318 Treat_Categorization_Errors_As_Warnings
:= True;
321 -- Enable GNATprove_Mode when using -gnatd.F switch
323 if Debug_Flag_Dot_FF
then
324 GNATprove_Mode
:= True;
327 -- GNATprove_Mode is also activated by default in the gnat2why
330 if GNATprove_Mode
then
332 -- Turn off inlining, which would confuse formal verification output
335 Front_End_Inlining
:= False;
336 Inline_Active
:= False;
338 -- Issue warnings for failure to inline subprograms, as otherwise
339 -- expected in GNATprove mode for the local subprograms without
342 Ineffective_Inline_Warnings
:= True;
344 -- Disable front-end optimizations, to keep the tree as close to the
345 -- source code as possible, and also to avoid inconsistencies between
346 -- trees when using different optimization switches.
348 Optimization_Level
:= 0;
350 -- Enable some restrictions systematically to simplify the generated
351 -- code (and ease analysis). Note that restriction checks are also
352 -- disabled in SPARK mode, see Restrict.Check_Restriction, and user
353 -- specified Restrictions pragmas are ignored, see
354 -- Sem_Prag.Process_Restrictions_Or_Restriction_Warnings.
356 Restrict
.Restrictions
.Set
(No_Initialize_Scalars
) := True;
358 -- Note: at this point we used to suppress various checks, but that
359 -- is not what we want. We need the semantic processing for these
360 -- checks (which will set flags like Do_Overflow_Check, showing the
361 -- points at which potential checks are required semantically). We
362 -- don't want the expansion associated with these checks, but that
363 -- happens anyway because this expansion is simply not done in the
364 -- SPARK version of the expander.
366 -- On the contrary, we need to enable explicitly all language checks,
367 -- as they may have been suppressed by the use of switch -gnatp.
369 Suppress_Options
.Suppress
:= (others => False);
371 -- Turn off dynamic elaboration checks. SPARK mode depends on the
372 -- use of the static elaboration mode.
374 Dynamic_Elaboration_Checks
:= False;
376 -- Detect overflow on unconstrained floating-point types, such as
377 -- the predefined types Float, Long_Float and Long_Long_Float from
378 -- package Standard. Not necessary if float overflows are checked
379 -- (Machine_Overflow true), since appropriate Do_Overflow_Check flags
380 -- will be set in any case.
382 Check_Float_Overflow
:= not Machine_Overflows_On_Target
;
384 -- Set STRICT mode for overflow checks if not set explicitly. This
385 -- prevents suppressing of overflow checks by default, in code down
388 if Suppress_Options
.Overflow_Mode_General
= Not_Set
then
389 Suppress_Options
.Overflow_Mode_General
:= Strict
;
390 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
393 -- Kill debug of generated code, since it messes up sloc values
395 Debug_Generated_Code
:= False;
397 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
398 -- as it is needed for computing effects of subprograms in the formal
399 -- verification backend.
403 -- Polling mode forced off, since it generates confusing junk
405 Polling_Required
:= False;
407 -- Set operating mode to Check_Semantics, but a light front-end
408 -- expansion is still performed.
410 Operating_Mode
:= Check_Semantics
;
412 -- Enable assertions, since they give valuable extra information for
413 -- formal verification.
415 Assertions_Enabled
:= True;
417 -- Disable validity checks, since it generates code raising
418 -- exceptions for invalid data, which confuses GNATprove. Invalid
419 -- data is directly detected by GNATprove's flow analysis.
421 Validity_Checks_On
:= False;
423 -- Turn off style check options since we are not interested in any
424 -- front-end warnings when we are getting SPARK output.
426 Reset_Style_Check_Options
;
428 -- Suppress the generation of name tables for enumerations, which are
429 -- not needed for formal verification, and fall outside the SPARK
430 -- subset (use of pointers).
432 Global_Discard_Names
:= True;
434 -- Suppress the expansion of tagged types and dispatching calls,
435 -- which lead to the generation of non-SPARK code (use of pointers),
436 -- which is more complex to formally verify than the original source.
438 Tagged_Type_Expansion
:= False;
441 -- Set Configurable_Run_Time mode if system.ads flag set or if the
442 -- special debug flag -gnatdY is set.
444 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
445 Configurable_Run_Time_Mode
:= True;
448 -- Set -gnatR3m mode if debug flag A set
450 if Debug_Flag_AA
then
451 Back_Annotate_Rep_Info
:= True;
452 List_Representation_Info
:= 1;
453 List_Representation_Info_Mechanisms
:= True;
456 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
458 if Debug_Flag_Dot_A
then
459 Ttypes
.Target_Strict_Alignment
:= True;
462 -- Increase size of allocated entities if debug flag -gnatd.N is set
464 if Debug_Flag_Dot_NN
then
465 Atree
.Num_Extension_Nodes
:= Atree
.Num_Extension_Nodes
+ 1;
468 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
469 -- is enabled. The front end's layout phase currently treats types that
470 -- have discriminant-dependent arrays as not being static even when a
471 -- discriminant constraint on the type is static, and this leads to
472 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
474 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
475 Static_Dispatch_Tables
:= False;
478 -- Flip endian mode if -gnatd8 set
481 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
484 -- Activate front end layout if debug flag -gnatdF is set
486 if Debug_Flag_FF
then
487 Targparm
.Frontend_Layout_On_Target
:= True;
490 -- Set and check exception mechanism
492 if Targparm
.ZCX_By_Default_On_Target
then
493 Exception_Mechanism
:= Back_End_Exceptions
;
496 -- Set proper status for overflow check mechanism
498 -- If already set (by -gnato or above in SPARK or CodePeer mode) then we
499 -- have nothing to do.
501 if Opt
.Suppress_Options
.Overflow_Mode_General
/= Not_Set
then
504 -- Otherwise set overflow mode defaults
507 -- Overflow checks are on by default (Suppress set False) except in
508 -- GNAT_Mode, where we want them off by default (we are not ready to
509 -- enable overflow checks in the compiler yet, for one thing the case
510 -- of 64-bit checks needs System.Arith_64 which is not a compiler
511 -- unit and it is a pain to try to include it in the compiler.
513 Suppress_Options
.Suppress
(Overflow_Check
) := GNAT_Mode
;
515 -- Set appropriate default overflow handling mode. Note: at present
516 -- we set STRICT in all three of the following cases. They are
517 -- separated because in the future we may make different choices.
519 -- By default set STRICT mode if -gnatg in effect
522 Suppress_Options
.Overflow_Mode_General
:= Strict
;
523 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
525 -- If we have backend divide and overflow checks, then by default
526 -- overflow checks are STRICT. Historically this code used to also
527 -- activate overflow checks, although no target currently has these
528 -- flags set, so this was dead code anyway.
530 elsif Targparm
.Backend_Divide_Checks_On_Target
532 Targparm
.Backend_Overflow_Checks_On_Target
534 Suppress_Options
.Overflow_Mode_General
:= Strict
;
535 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
537 -- Otherwise for now, default is STRICT mode. This may change in the
538 -- future, but for now this is the compatible behavior with previous
542 Suppress_Options
.Overflow_Mode_General
:= Strict
;
543 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
547 -- Set default for atomic synchronization. As this synchronization
548 -- between atomic accesses can be expensive, and not typically needed
549 -- on some targets, an optional target parameter can turn the option
550 -- off. Note Atomic Synchronization is implemented as check.
552 Suppress_Options
.Suppress
(Atomic_Synchronization
) :=
553 not Atomic_Sync_Default_On_Target
;
555 -- Set switch indicating if back end can handle limited types, and
556 -- guarantee that no incorrect copies are made (e.g. in the context
557 -- of an if or case expression).
559 -- Debug flag -gnatd.L decisively sets usage on
561 if Debug_Flag_Dot_LL
then
562 Back_End_Handles_Limited_Types
:= True;
564 -- If no debug flag, usage off for AAMP, VM, SCIL cases
567 or else VM_Target
/= No_VM
568 or else Generate_SCIL
570 Back_End_Handles_Limited_Types
:= False;
572 -- Otherwise normal gcc back end, for now still turn flag off by
573 -- default, since there are unresolved problems in the front end.
576 Back_End_Handles_Limited_Types
:= False;
579 -- If the inlining level has not been set by the user, compute it from
580 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
582 if Inline_Level
= 0 then
583 if Optimization_Level
< 3 then
590 -- Treat -gnatn as equivalent to -gnatN for non-GCC targets
592 if Inline_Active
and not Front_End_Inlining
then
594 -- We really should have a tag for this, what if we added a new
595 -- back end some day, it would not be true for this test, but it
596 -- would be non-GCC, so this is a bit troublesome ???
598 Front_End_Inlining
:= VM_Target
/= No_VM
or else AAMP_On_Target
;
601 -- Set back end inlining indication
605 -- No back end inlining if inlining is suppressed
607 not Suppress_All_Inlining
609 -- No back end inlining available for VM targets
611 and then VM_Target
= No_VM
613 -- No back end inlining available on AAMP
615 and then not AAMP_On_Target
617 -- No back end inlining in GNATprove mode, since it just confuses
618 -- the formal verification process.
620 and then not GNATprove_Mode
622 -- No back end inlining if front end inlining explicitly enabled.
623 -- Done to minimize the output differences to customers still using
624 -- this deprecated switch; in addition, this behavior reduces the
625 -- output differences in old tests.
627 and then not Front_End_Inlining
629 -- Back end inlining is disabled if debug flag .z is set
631 and then not Debug_Flag_Dot_Z
;
633 -- Output warning if -gnateE specified and cannot be supported
635 if Exception_Extra_Info
636 and then Restrict
.No_Exception_Handlers_Set
640 ("warning: extra exception information (-gnateE) was specified");
643 ("warning: this capability is not available in this configuration");
648 -- Finally capture adjusted value of Suppress_Options as the initial
649 -- value for Scope_Suppress, which will be modified as we move from
650 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
652 Sem
.Scope_Suppress
:= Opt
.Suppress_Options
;
653 end Adjust_Global_Switches
;
659 procedure Check_Bad_Body
is
660 Sname
: Unit_Name_Type
;
661 Src_Ind
: Source_File_Index
;
662 Fname
: File_Name_Type
;
664 procedure Bad_Body_Error
(Msg
: String);
665 -- Issue message for bad body found
671 procedure Bad_Body_Error
(Msg
: String) is
673 Error_Msg_N
(Msg
, Main_Unit_Node
);
674 Error_Msg_File_1
:= Fname
;
675 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
678 -- Start of processing for Check_Bad_Body
681 -- Nothing to do if we are only checking syntax, because we don't know
682 -- enough to know if we require or forbid a body in this case.
684 if Operating_Mode
= Check_Syntax
then
688 -- Check for body not allowed
690 if (Main_Kind
= N_Package_Declaration
691 and then not Body_Required
(Main_Unit_Node
))
692 or else (Main_Kind
= N_Generic_Package_Declaration
693 and then not Body_Required
(Main_Unit_Node
))
694 or else Main_Kind
= N_Package_Renaming_Declaration
695 or else Main_Kind
= N_Subprogram_Renaming_Declaration
696 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
697 in N_Generic_Instantiation
699 Sname
:= Unit_Name
(Main_Unit
);
701 -- If we do not already have a body name, then get the body name
703 if not Is_Body_Name
(Sname
) then
704 Sname
:= Get_Body_Name
(Sname
);
707 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
708 Src_Ind
:= Load_Source_File
(Fname
);
710 -- Case where body is present and it is not a subunit. Exclude the
711 -- subunit case, because it has nothing to do with the package we are
712 -- compiling. It is illegal for a child unit and a subunit with the
713 -- same expanded name (RM 10.2(9)) to appear together in a partition,
714 -- but there is nothing to stop a compilation environment from having
715 -- both, and the test here simply allows that. If there is an attempt
716 -- to include both in a partition, this is diagnosed at bind time. In
717 -- Ada 83 mode this is not a warning case.
719 -- Note that in general we do not give the message if the file in
720 -- question does not look like a body. This includes weird cases,
721 -- but in particular means that if the file is just a No_Body pragma,
722 -- then we won't give the message (that's the whole point of this
723 -- pragma, to be used this way and to cause the body file to be
724 -- ignored in this context).
726 if Src_Ind
/= No_Source_File
727 and then Source_File_Is_Body
(Src_Ind
)
729 Errout
.Finalize
(Last_Call
=> False);
731 Error_Msg_Unit_1
:= Sname
;
733 -- Ada 83 case of a package body being ignored. This is not an
734 -- error as far as the Ada 83 RM is concerned, but it is almost
735 -- certainly not what is wanted so output a warning. Give this
736 -- message only if there were no errors, since otherwise it may
737 -- be incorrect (we may have misinterpreted a junk spec as not
738 -- needing a body when it really does).
740 if Main_Kind
= N_Package_Declaration
741 and then Ada_Version
= Ada_83
742 and then Operating_Mode
= Generate_Code
743 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
744 and then not Compilation_Errors
747 ("package $$ does not require a body??", Main_Unit_Node
);
748 Error_Msg_File_1
:= Fname
;
749 Error_Msg_N
("body in file{ will be ignored??", Main_Unit_Node
);
751 -- Ada 95 cases of a body file present when no body is
752 -- permitted. This we consider to be an error.
755 -- For generic instantiations, we never allow a body
757 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
))) in
758 N_Generic_Instantiation
761 ("generic instantiation for $$ does not allow a body");
763 -- A library unit that is a renaming never allows a body
765 elsif Main_Kind
in N_Renaming_Declaration
then
767 ("renaming declaration for $$ does not allow a body!");
769 -- Remaining cases are packages and generic packages. Here
770 -- we only do the test if there are no previous errors,
771 -- because if there are errors, they may lead us to
772 -- incorrectly believe that a package does not allow a
773 -- body when in fact it does.
775 elsif not Compilation_Errors
then
776 if Main_Kind
= N_Package_Declaration
then
778 ("package $$ does not allow a body!");
780 elsif Main_Kind
= N_Generic_Package_Declaration
then
782 ("generic package $$ does not allow a body!");
795 procedure Check_Rep_Info
is
797 if List_Representation_Info
/= 0
798 or else List_Representation_Info_Mechanisms
803 ("cannot generate representation information, no code generated");
810 ----------------------------------------
811 -- Post_Compilation_Validation_Checks --
812 ----------------------------------------
814 procedure Post_Compilation_Validation_Checks
is
816 -- Validate alignment check warnings. In some cases we generate warnings
817 -- about possible alignment errors because we don't know the alignment
818 -- that will be chosen by the back end. This routine is in charge of
819 -- getting rid of those warnings if we can tell they are not needed.
821 Checks
.Validate_Alignment_Check_Warnings
;
823 -- Validate unchecked conversions (using the values for size and
824 -- alignment annotated by the backend where possible).
826 Sem_Ch13
.Validate_Unchecked_Conversions
;
828 -- Validate address clauses (again using alignment values annotated
829 -- by the backend where possible).
831 Sem_Ch13
.Validate_Address_Clauses
;
833 -- Validate independence pragmas (again using values annotated by
834 -- the back end for component layout etc.)
836 Sem_Ch13
.Validate_Independence
;
837 end Post_Compilation_Validation_Checks
;
839 -- Start of processing for Gnat1drv
842 -- This inner block is set up to catch assertion errors and constraint
843 -- errors. Since the code for handling these errors can cause another
844 -- exception to be raised (namely Unrecoverable_Error), we need two
845 -- nested blocks, so that the outer one handles unrecoverable error.
848 -- Initialize all packages. For the most part, these initialization
849 -- calls can be made in any order. Exceptions are as follows:
851 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
852 -- because it initializes a table filled by Scan_Compiler_Arguments.
858 Scan_Compiler_Arguments
;
859 Osint
.Add_Default_Search_Dirs
;
880 Sem_Type
.Init_Interp_Tables
;
882 -- Capture compilation date and time
884 Opt
.Compilation_Time
:= System
.OS_Lib
.Current_Time_String
;
886 -- Get the target parameters only when -gnats is not used, to avoid
887 -- failing when there is no default runtime.
889 if Operating_Mode
/= Check_Syntax
then
891 -- Acquire target parameters from system.ads (package System source)
893 Targparm_Acquire
: declare
896 S
: Source_File_Index
;
900 Name_Buffer
(1 .. 10) := "system.ads";
903 S
:= Load_Source_File
(N
);
905 -- Failed to read system.ads, fatal error
907 if S
= No_Source_File
then
909 ("fatal error, run-time library not installed correctly");
910 Write_Line
("cannot locate file system.ads");
911 raise Unrecoverable_Error
;
913 -- Read system.ads successfully, remember its source index
916 System_Source_File_Index
:= S
;
919 Targparm
.Get_Target_Parameters
920 (System_Text
=> Source_Text
(S
),
921 Source_First
=> Source_First
(S
),
922 Source_Last
=> Source_Last
(S
),
923 Make_Id
=> Tbuild
.Make_Id
'Access,
924 Make_SC
=> Tbuild
.Make_SC
'Access,
925 Set_RND
=> Tbuild
.Set_RND
'Access);
927 -- Acquire configuration pragma information from Targparm
929 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
930 end Targparm_Acquire
;
933 -- Perform various adjustments and settings of global switches
935 Adjust_Global_Switches
;
937 -- Output copyright notice if full list mode unless we have a list
938 -- file, in which case we defer this so that it is output in the file.
940 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
942 -- Debug flag gnatd7 suppresses this copyright notice
944 and then not Debug_Flag_7
948 Write_Str
(Gnat_Version_String
);
950 Write_Str
("Copyright 1992-" & Current_Year
951 & ", Free Software Foundation, Inc.");
955 -- Check we do not have more than one source file, this happens only in
956 -- the case where the driver is called directly, it cannot happen when
957 -- gnat1 is invoked from gcc in the normal case.
959 if Osint
.Number_Of_Files
/= 1 then
962 Osint
.Fail
("you must provide one source file");
964 elsif Usage_Requested
then
968 -- Generate target dependent output file if requested
970 if Target_Dependent_Info_Write_Name
/= null then
971 Set_Targ
.Write_Target_Dependent_Values
;
974 -- Call the front end
976 Original_Operating_Mode
:= Operating_Mode
;
979 -- Exit with errors if the main source could not be parsed.
981 if Sinput
.Main_Source_File
= No_Source_File
then
982 Errout
.Finalize
(Last_Call
=> True);
983 Errout
.Output_Messages
;
984 Exit_Program
(E_Errors
);
987 Main_Unit_Node
:= Cunit
(Main_Unit
);
988 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
991 -- In CodePeer mode we always delete old SCIL files before regenerating
992 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
993 -- files generated by CodePeer itself.
995 if CodePeer_Mode
then
996 Comperr
.Delete_SCIL_Files
;
999 -- Exit if compilation errors detected
1001 Errout
.Finalize
(Last_Call
=> False);
1003 if Compilation_Errors
then
1005 Post_Compilation_Validation_Checks
;
1006 Errout
.Output_Messages
;
1009 -- Generate ALI file if specially requested
1011 if Opt
.Force_ALI_Tree_File
then
1012 Write_ALI
(Object
=> False);
1016 Errout
.Finalize
(Last_Call
=> True);
1017 Exit_Program
(E_Errors
);
1020 -- Set Generate_Code on main unit and its spec. We do this even if are
1021 -- not generating code, since Lib-Writ uses this to determine which
1022 -- units get written in the ali file.
1024 Set_Generate_Code
(Main_Unit
);
1026 -- If we have a corresponding spec, and it comes from source or it is
1027 -- not a generated spec for a child subprogram body, then we need object
1028 -- code for the spec unit as well.
1030 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
1031 and then not Acts_As_Spec
(Main_Unit_Node
)
1033 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
1034 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
1039 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
1043 -- Case of no code required to be generated, exit indicating no error
1045 if Original_Operating_Mode
= Check_Syntax
then
1047 Errout
.Finalize
(Last_Call
=> True);
1048 Errout
.Output_Messages
;
1053 -- Use a goto instead of calling Exit_Program so that finalization
1056 goto End_Of_Program
;
1058 elsif Original_Operating_Mode
= Check_Semantics
then
1059 Back_End_Mode
:= Declarations_Only
;
1061 -- All remaining cases are cases in which the user requested that code
1062 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
1063 -- can in fact satisfy this request.
1065 -- Cannot generate code if someone has turned off code generation for
1066 -- any reason at all. We will try to figure out a reason below.
1068 elsif Operating_Mode
/= Generate_Code
then
1069 Back_End_Mode
:= Skip
;
1071 -- We can generate code for a subprogram body unless there were missing
1072 -- subunits. Note that we always generate code for all generic units (a
1073 -- change from some previous versions of GNAT).
1075 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
1076 Back_End_Mode
:= Generate_Object
;
1078 -- We can generate code for a package body unless there are subunits
1079 -- missing (note that we always generate code for generic units, which
1080 -- is a change from some earlier versions of GNAT).
1082 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
1083 Back_End_Mode
:= Generate_Object
;
1085 -- We can generate code for a package declaration or a subprogram
1086 -- declaration only if it does not required a body.
1088 elsif Nkind_In
(Main_Kind
,
1089 N_Package_Declaration
,
1090 N_Subprogram_Declaration
)
1092 (not Body_Required
(Main_Unit_Node
)
1094 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
1096 Back_End_Mode
:= Generate_Object
;
1098 -- We can generate code for a generic package declaration of a generic
1099 -- subprogram declaration only if does not require a body.
1101 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
1102 N_Generic_Subprogram_Declaration
)
1103 and then not Body_Required
(Main_Unit_Node
)
1105 Back_End_Mode
:= Generate_Object
;
1107 -- Compilation units that are renamings do not require bodies, so we can
1108 -- generate code for them.
1110 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
1111 N_Subprogram_Renaming_Declaration
)
1113 Back_End_Mode
:= Generate_Object
;
1115 -- Compilation units that are generic renamings do not require bodies
1116 -- so we can generate code for them.
1118 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
1119 Back_End_Mode
:= Generate_Object
;
1121 -- It is not an error to analyze in CodePeer mode a spec which requires
1122 -- a body, in order to generate SCIL for this spec.
1124 elsif CodePeer_Mode
then
1125 Back_End_Mode
:= Generate_Object
;
1127 -- It is not an error to analyze in GNATprove mode a spec which requires
1128 -- a body, when the body is not available. During frame condition
1129 -- generation, the corresponding ALI file is generated. During
1130 -- analysis, the spec is analyzed.
1132 elsif GNATprove_Mode
then
1133 Back_End_Mode
:= Declarations_Only
;
1135 -- In all other cases (specs which have bodies, generics, and bodies
1136 -- where subunits are missing), we cannot generate code and we generate
1137 -- a warning message. Note that generic instantiations are gone at this
1138 -- stage since they have been replaced by their instances.
1141 Back_End_Mode
:= Skip
;
1144 -- At this stage Back_End_Mode is set to indicate if the backend should
1145 -- be called to generate code. If it is Skip, then code generation has
1146 -- been turned off, even though code was requested by the original
1147 -- command. This is not an error from the user point of view, but it is
1148 -- an error from the point of view of the gcc driver, so we must exit
1149 -- with an error status.
1151 -- We generate an informative message (from the gcc point of view, it
1152 -- is an error message, but from the users point of view this is not an
1153 -- error, just a consequence of compiling something that cannot
1156 if Back_End_Mode
= Skip
then
1158 Write_Str
("cannot generate code for ");
1159 Write_Str
("file ");
1160 Write_Name
(Unit_File_Name
(Main_Unit
));
1162 if Subunits_Missing
then
1163 Write_Str
(" (missing subunits)");
1166 -- Force generation of ALI file, for backward compatibility
1168 Opt
.Force_ALI_Tree_File
:= True;
1170 elsif Main_Kind
= N_Subunit
then
1171 Write_Str
(" (subunit)");
1174 -- Force generation of ALI file, for backward compatibility
1176 Opt
.Force_ALI_Tree_File
:= True;
1178 elsif Main_Kind
= N_Subprogram_Declaration
then
1179 Write_Str
(" (subprogram spec)");
1182 -- Generic package body in GNAT implementation mode
1184 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
1185 Write_Str
(" (predefined generic)");
1188 -- Force generation of ALI file, for backward compatibility
1190 Opt
.Force_ALI_Tree_File
:= True;
1192 -- Only other case is a package spec
1195 Write_Str
(" (package spec)");
1199 Set_Standard_Output
;
1201 Post_Compilation_Validation_Checks
;
1202 Errout
.Finalize
(Last_Call
=> True);
1203 Errout
.Output_Messages
;
1207 -- Generate ALI file if specially requested, or for missing subunits,
1208 -- subunits or predefined generic.
1210 if Opt
.Force_ALI_Tree_File
then
1211 Write_ALI
(Object
=> False);
1217 -- Exit program with error indication, to kill object file
1219 Exit_Program
(E_No_Code
);
1222 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1223 -- as indicated by Back_Annotate_Rep_Info being set to True.
1225 -- We don't call for annotations on a subunit, because to process those
1226 -- the back-end requires that the parent(s) be properly compiled.
1228 -- Annotation is suppressed for targets where front-end layout is
1229 -- enabled, because the front end determines representations.
1231 -- Annotation is also suppressed in the case of compiling for a VM,
1232 -- since representations are largely symbolic there.
1234 if Back_End_Mode
= Declarations_Only
1236 (not (Back_Annotate_Rep_Info
or Generate_SCIL
or GNATprove_Mode
)
1237 or else Main_Kind
= N_Subunit
1238 or else Targparm
.Frontend_Layout_On_Target
1239 or else Targparm
.VM_Target
/= No_VM
)
1241 Post_Compilation_Validation_Checks
;
1242 Errout
.Finalize
(Last_Call
=> True);
1243 Errout
.Output_Messages
;
1244 Write_ALI
(Object
=> False);
1252 -- Ensure that we properly register a dependency on system.ads, since
1253 -- even if we do not semantically depend on this, Targparm has read
1254 -- system parameters from the system.ads file.
1256 Lib
.Writ
.Ensure_System_Dependency
;
1258 -- Add dependencies, if any, on preprocessing data file and on
1259 -- preprocessing definition file(s).
1261 Prepcomp
.Add_Dependencies
;
1263 -- In gnatprove mode we're writing the ALI much earlier than usual
1264 -- as flow analysis needs the file present in order to append its
1265 -- own globals to it.
1267 if GNATprove_Mode
then
1269 -- Note: In GNATprove mode, an "object" file is always generated as
1270 -- the result of calling gnat1 or gnat2why, although this is not the
1271 -- same as the object file produced for compilation.
1273 Write_ALI
(Object
=> True);
1276 -- Back end needs to explicitly unlock tables it needs to touch
1289 -- Here we call the back end to generate the output code
1291 Generating_Code
:= True;
1292 Back_End
.Call_Back_End
(Back_End_Mode
);
1294 -- Once the backend is complete, we unlock the names table. This call
1295 -- allows a few extra entries, needed for example for the file name for
1296 -- the library file output.
1300 -- Generate the call-graph output of dispatching calls
1302 Exp_CG
.Generate_CG_Output
;
1304 -- Perform post compilation validation checks
1306 Post_Compilation_Validation_Checks
;
1308 -- Now we complete output of errors, rep info and the tree info. These
1309 -- are delayed till now, since it is perfectly possible for gigi to
1310 -- generate errors, modify the tree (in particular by setting flags
1311 -- indicating that elaboration is required, and also to back annotate
1312 -- representation information for List_Rep_Info.
1314 Errout
.Finalize
(Last_Call
=> True);
1315 Errout
.Output_Messages
;
1316 List_Rep_Info
(Ttypes
.Bytes_Big_Endian
);
1317 Inline
.List_Inlining_Info
;
1319 -- Only write the library if the backend did not generate any error
1320 -- messages. Otherwise signal errors to the driver program so that
1321 -- there will be no attempt to generate an object file.
1323 if Compilation_Errors
then
1325 Exit_Program
(E_Errors
);
1328 if not GNATprove_Mode
then
1329 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
));
1332 if not Compilation_Errors
then
1334 -- In case of ada backends, we need to make sure that the generated
1335 -- object file has a timestamp greater than the ALI file. We do this
1336 -- to make gnatmake happy when checking the ALI and obj timestamps,
1337 -- where it expects the object file being written after the ali file.
1339 -- Gnatmake's assumption is true for gcc platforms where the gcc
1340 -- wrapper needs to call the assembler after calling gnat1, but is
1341 -- not true for ada backends, where the object files are created
1342 -- directly by gnat1 (so are created before the ali file).
1344 Back_End
.Gen_Or_Update_Object_File
;
1347 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1348 -- Write_ALI may in fact result in further tree decoration from the
1349 -- original tree file. Note that we dump the tree just before generating
1350 -- it, so that the dump will exactly reflect what is written out.
1355 -- Finalize name table and we are all done
1360 -- Handle fatal internal compiler errors
1362 when Rtsfind
.RE_Not_Available
=>
1363 Comperr
.Compiler_Abort
("RE_Not_Available");
1365 when System
.Assertions
.Assert_Failure
=>
1366 Comperr
.Compiler_Abort
("Assert_Failure");
1368 when Constraint_Error
=>
1369 Comperr
.Compiler_Abort
("Constraint_Error");
1371 when Program_Error
=>
1372 Comperr
.Compiler_Abort
("Program_Error");
1374 when Storage_Error
=>
1376 -- Assume this is a bug. If it is real, the message will in any case
1377 -- say Storage_Error, giving a strong hint.
1379 Comperr
.Compiler_Abort
("Storage_Error");
1385 -- The outer exception handles an unrecoverable error
1388 when Unrecoverable_Error
=>
1389 Errout
.Finalize
(Last_Call
=> True);
1390 Errout
.Output_Messages
;
1393 Write_Str
("compilation abandoned");
1396 Set_Standard_Output
;
1399 Exit_Program
(E_Errors
);