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 marked as suppressed by the use of switch
370 Suppress_Options
.Suppress
:= (others => False);
372 -- Turn off dynamic elaboration checks: generates inconsistencies in
373 -- trees between specs compiled as part of a main unit or as part of
376 -- Comment is incomplete, SPARK semantics rely on static mode no???
378 Dynamic_Elaboration_Checks
:= False;
380 -- Detect overflow on unconstrained floating-point types, such as
381 -- the predefined types Float, Long_Float and Long_Long_Float from
382 -- package Standard. Not necessary if float overflows are checked
383 -- (Machine_Overflow true), since appropriate Do_Overflow_Check flags
384 -- will be set in any case.
386 Check_Float_Overflow
:= not Machine_Overflows_On_Target
;
388 -- Set STRICT mode for overflow checks if not set explicitly. This
389 -- prevents suppressing of overflow checks by default, in code down
392 if Suppress_Options
.Overflow_Mode_General
= Not_Set
then
393 Suppress_Options
.Overflow_Mode_General
:= Strict
;
394 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
397 -- Kill debug of generated code, since it messes up sloc values
399 Debug_Generated_Code
:= False;
401 -- Turn cross-referencing on in case it was disabled (e.g. by -gnatD)
402 -- as it is needed for computing effects of subprograms in the formal
403 -- verification backend.
407 -- Polling mode forced off, since it generates confusing junk
409 Polling_Required
:= False;
411 -- Set operating mode to Check_Semantics, but a light front-end
412 -- expansion is still performed.
414 Operating_Mode
:= Check_Semantics
;
416 -- Enable assertions, since they give valuable extra information for
417 -- formal verification.
419 Assertions_Enabled
:= True;
421 -- Disable validity checks, since it generates code raising
422 -- exceptions for invalid data, which confuses GNATprove. Invalid
423 -- data is directly detected by GNATprove's flow analysis.
425 Validity_Checks_On
:= False;
427 -- Turn off style check options since we are not interested in any
428 -- front-end warnings when we are getting SPARK output.
430 Reset_Style_Check_Options
;
432 -- Suppress the generation of name tables for enumerations, which are
433 -- not needed for formal verification, and fall outside the SPARK
434 -- subset (use of pointers).
436 Global_Discard_Names
:= True;
438 -- Suppress the expansion of tagged types and dispatching calls,
439 -- which lead to the generation of non-SPARK code (use of pointers),
440 -- which is more complex to formally verify than the original source.
442 Tagged_Type_Expansion
:= False;
445 -- Set Configurable_Run_Time mode if system.ads flag set or if the
446 -- special debug flag -gnatdY is set.
448 if Targparm
.Configurable_Run_Time_On_Target
or Debug_Flag_YY
then
449 Configurable_Run_Time_Mode
:= True;
452 -- Set -gnatR3m mode if debug flag A set
454 if Debug_Flag_AA
then
455 Back_Annotate_Rep_Info
:= True;
456 List_Representation_Info
:= 1;
457 List_Representation_Info_Mechanisms
:= True;
460 -- Force Target_Strict_Alignment true if debug flag -gnatd.a is set
462 if Debug_Flag_Dot_A
then
463 Ttypes
.Target_Strict_Alignment
:= True;
466 -- Increase size of allocated entities if debug flag -gnatd.N is set
468 if Debug_Flag_Dot_NN
then
469 Atree
.Num_Extension_Nodes
:= Atree
.Num_Extension_Nodes
+ 1;
472 -- Disable static allocation of dispatch tables if -gnatd.t or if layout
473 -- is enabled. The front end's layout phase currently treats types that
474 -- have discriminant-dependent arrays as not being static even when a
475 -- discriminant constraint on the type is static, and this leads to
476 -- problems with subtypes of type Ada.Tags.Dispatch_Table_Wrapper. ???
478 if Debug_Flag_Dot_T
or else Frontend_Layout_On_Target
then
479 Static_Dispatch_Tables
:= False;
482 -- Flip endian mode if -gnatd8 set
485 Ttypes
.Bytes_Big_Endian
:= not Ttypes
.Bytes_Big_Endian
;
488 -- Activate front end layout if debug flag -gnatdF is set
490 if Debug_Flag_FF
then
491 Targparm
.Frontend_Layout_On_Target
:= True;
494 -- Set and check exception mechanism
496 if Targparm
.ZCX_By_Default_On_Target
then
497 Exception_Mechanism
:= Back_End_Exceptions
;
500 -- Set proper status for overflow check mechanism
502 -- If already set (by -gnato or above in SPARK or CodePeer mode) then we
503 -- have nothing to do.
505 if Opt
.Suppress_Options
.Overflow_Mode_General
/= Not_Set
then
508 -- Otherwise set overflow mode defaults
511 -- Overflow checks are on by default (Suppress set False) except in
512 -- GNAT_Mode, where we want them off by default (we are not ready to
513 -- enable overflow checks in the compiler yet, for one thing the case
514 -- of 64-bit checks needs System.Arith_64 which is not a compiler
515 -- unit and it is a pain to try to include it in the compiler.
517 Suppress_Options
.Suppress
(Overflow_Check
) := GNAT_Mode
;
519 -- Set appropriate default overflow handling mode. Note: at present
520 -- we set STRICT in all three of the following cases. They are
521 -- separated because in the future we may make different choices.
523 -- By default set STRICT mode if -gnatg in effect
526 Suppress_Options
.Overflow_Mode_General
:= Strict
;
527 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
529 -- If we have backend divide and overflow checks, then by default
530 -- overflow checks are STRICT. Historically this code used to also
531 -- activate overflow checks, although no target currently has these
532 -- flags set, so this was dead code anyway.
534 elsif Targparm
.Backend_Divide_Checks_On_Target
536 Targparm
.Backend_Overflow_Checks_On_Target
538 Suppress_Options
.Overflow_Mode_General
:= Strict
;
539 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
541 -- Otherwise for now, default is STRICT mode. This may change in the
542 -- future, but for now this is the compatible behavior with previous
546 Suppress_Options
.Overflow_Mode_General
:= Strict
;
547 Suppress_Options
.Overflow_Mode_Assertions
:= Strict
;
551 -- Set default for atomic synchronization. As this synchronization
552 -- between atomic accesses can be expensive, and not typically needed
553 -- on some targets, an optional target parameter can turn the option
554 -- off. Note Atomic Synchronization is implemented as check.
556 Suppress_Options
.Suppress
(Atomic_Synchronization
) :=
557 not Atomic_Sync_Default_On_Target
;
559 -- Set switch indicating if back end can handle limited types, and
560 -- guarantee that no incorrect copies are made (e.g. in the context
561 -- of an if or case expression).
563 -- Debug flag -gnatd.L decisively sets usage on
565 if Debug_Flag_Dot_LL
then
566 Back_End_Handles_Limited_Types
:= True;
568 -- If no debug flag, usage off for AAMP, VM, SCIL cases
571 or else VM_Target
/= No_VM
572 or else Generate_SCIL
574 Back_End_Handles_Limited_Types
:= False;
576 -- Otherwise normal gcc back end, for now still turn flag off by
577 -- default, since there are unresolved problems in the front end.
580 Back_End_Handles_Limited_Types
:= False;
583 -- If the inlining level has not been set by the user, compute it from
584 -- the optimization level: 1 at -O1/-O2 (and -Os), 2 at -O3 and above.
586 if Inline_Level
= 0 then
587 if Optimization_Level
< 3 then
594 -- Treat -gnatn as equivalent to -gnatN for non-GCC targets
596 if Inline_Active
and not Front_End_Inlining
then
598 -- We really should have a tag for this, what if we added a new
599 -- back end some day, it would not be true for this test, but it
600 -- would be non-GCC, so this is a bit troublesome ???
602 Front_End_Inlining
:= VM_Target
/= No_VM
or else AAMP_On_Target
;
605 -- Set back end inlining indication
609 -- No back end inlining if inlining is suppressed
611 not Suppress_All_Inlining
613 -- No back end inlining available for VM targets
615 and then VM_Target
= No_VM
617 -- No back end inlining available on AAMP
619 and then not AAMP_On_Target
621 -- No back end inlining in GNATprove mode, since it just confuses
622 -- the formal verification process.
624 and then not GNATprove_Mode
626 -- No back end inlining if front end inlining explicitly enabled.
627 -- Done to minimize the output differences to customers still using
628 -- this deprecated switch; in addition, this behavior reduces the
629 -- output differences in old tests.
631 and then not Front_End_Inlining
633 -- Back end inlining is disabled if debug flag .z is set
635 and then not Debug_Flag_Dot_Z
;
637 -- Output warning if -gnateE specified and cannot be supported
639 if Exception_Extra_Info
640 and then Restrict
.No_Exception_Handlers_Set
644 ("warning: extra exception information (-gnateE) was specified");
647 ("warning: this capability is not available in this configuration");
652 -- Finally capture adjusted value of Suppress_Options as the initial
653 -- value for Scope_Suppress, which will be modified as we move from
654 -- scope to scope (by Suppress/Unsuppress/Overflow_Checks pragmas).
656 Sem
.Scope_Suppress
:= Opt
.Suppress_Options
;
657 end Adjust_Global_Switches
;
663 procedure Check_Bad_Body
is
664 Sname
: Unit_Name_Type
;
665 Src_Ind
: Source_File_Index
;
666 Fname
: File_Name_Type
;
668 procedure Bad_Body_Error
(Msg
: String);
669 -- Issue message for bad body found
675 procedure Bad_Body_Error
(Msg
: String) is
677 Error_Msg_N
(Msg
, Main_Unit_Node
);
678 Error_Msg_File_1
:= Fname
;
679 Error_Msg_N
("remove incorrect body in file{!", Main_Unit_Node
);
682 -- Start of processing for Check_Bad_Body
685 -- Nothing to do if we are only checking syntax, because we don't know
686 -- enough to know if we require or forbid a body in this case.
688 if Operating_Mode
= Check_Syntax
then
692 -- Check for body not allowed
694 if (Main_Kind
= N_Package_Declaration
695 and then not Body_Required
(Main_Unit_Node
))
696 or else (Main_Kind
= N_Generic_Package_Declaration
697 and then not Body_Required
(Main_Unit_Node
))
698 or else Main_Kind
= N_Package_Renaming_Declaration
699 or else Main_Kind
= N_Subprogram_Renaming_Declaration
700 or else Nkind
(Original_Node
(Unit
(Main_Unit_Node
)))
701 in N_Generic_Instantiation
703 Sname
:= Unit_Name
(Main_Unit
);
705 -- If we do not already have a body name, then get the body name
707 if not Is_Body_Name
(Sname
) then
708 Sname
:= Get_Body_Name
(Sname
);
711 Fname
:= Get_File_Name
(Sname
, Subunit
=> False);
712 Src_Ind
:= Load_Source_File
(Fname
);
714 -- Case where body is present and it is not a subunit. Exclude the
715 -- subunit case, because it has nothing to do with the package we are
716 -- compiling. It is illegal for a child unit and a subunit with the
717 -- same expanded name (RM 10.2(9)) to appear together in a partition,
718 -- but there is nothing to stop a compilation environment from having
719 -- both, and the test here simply allows that. If there is an attempt
720 -- to include both in a partition, this is diagnosed at bind time. In
721 -- Ada 83 mode this is not a warning case.
723 -- Note that in general we do not give the message if the file in
724 -- question does not look like a body. This includes weird cases,
725 -- but in particular means that if the file is just a No_Body pragma,
726 -- then we won't give the message (that's the whole point of this
727 -- pragma, to be used this way and to cause the body file to be
728 -- ignored in this context).
730 if Src_Ind
/= No_Source_File
731 and then Source_File_Is_Body
(Src_Ind
)
733 Errout
.Finalize
(Last_Call
=> False);
735 Error_Msg_Unit_1
:= Sname
;
737 -- Ada 83 case of a package body being ignored. This is not an
738 -- error as far as the Ada 83 RM is concerned, but it is almost
739 -- certainly not what is wanted so output a warning. Give this
740 -- message only if there were no errors, since otherwise it may
741 -- be incorrect (we may have misinterpreted a junk spec as not
742 -- needing a body when it really does).
744 if Main_Kind
= N_Package_Declaration
745 and then Ada_Version
= Ada_83
746 and then Operating_Mode
= Generate_Code
747 and then Distribution_Stub_Mode
/= Generate_Caller_Stub_Body
748 and then not Compilation_Errors
751 ("package $$ does not require a body??", Main_Unit_Node
);
752 Error_Msg_File_1
:= Fname
;
753 Error_Msg_N
("body in file{ will be ignored??", Main_Unit_Node
);
755 -- Ada 95 cases of a body file present when no body is
756 -- permitted. This we consider to be an error.
759 -- For generic instantiations, we never allow a body
761 if Nkind
(Original_Node
(Unit
(Main_Unit_Node
))) in
762 N_Generic_Instantiation
765 ("generic instantiation for $$ does not allow a body");
767 -- A library unit that is a renaming never allows a body
769 elsif Main_Kind
in N_Renaming_Declaration
then
771 ("renaming declaration for $$ does not allow a body!");
773 -- Remaining cases are packages and generic packages. Here
774 -- we only do the test if there are no previous errors,
775 -- because if there are errors, they may lead us to
776 -- incorrectly believe that a package does not allow a
777 -- body when in fact it does.
779 elsif not Compilation_Errors
then
780 if Main_Kind
= N_Package_Declaration
then
782 ("package $$ does not allow a body!");
784 elsif Main_Kind
= N_Generic_Package_Declaration
then
786 ("generic package $$ does not allow a body!");
799 procedure Check_Rep_Info
is
801 if List_Representation_Info
/= 0
802 or else List_Representation_Info_Mechanisms
807 ("cannot generate representation information, no code generated");
814 ----------------------------------------
815 -- Post_Compilation_Validation_Checks --
816 ----------------------------------------
818 procedure Post_Compilation_Validation_Checks
is
820 -- Validate alignment check warnings. In some cases we generate warnings
821 -- about possible alignment errors because we don't know the alignment
822 -- that will be chosen by the back end. This routine is in charge of
823 -- getting rid of those warnings if we can tell they are not needed.
825 Checks
.Validate_Alignment_Check_Warnings
;
827 -- Validate unchecked conversions (using the values for size and
828 -- alignment annotated by the backend where possible).
830 Sem_Ch13
.Validate_Unchecked_Conversions
;
832 -- Validate address clauses (again using alignment values annotated
833 -- by the backend where possible).
835 Sem_Ch13
.Validate_Address_Clauses
;
837 -- Validate independence pragmas (again using values annotated by
838 -- the back end for component layout etc.)
840 Sem_Ch13
.Validate_Independence
;
841 end Post_Compilation_Validation_Checks
;
843 -- Start of processing for Gnat1drv
846 -- This inner block is set up to catch assertion errors and constraint
847 -- errors. Since the code for handling these errors can cause another
848 -- exception to be raised (namely Unrecoverable_Error), we need two
849 -- nested blocks, so that the outer one handles unrecoverable error.
852 -- Initialize all packages. For the most part, these initialization
853 -- calls can be made in any order. Exceptions are as follows:
855 -- Lib.Initialize need to be called before Scan_Compiler_Arguments,
856 -- because it initializes a table filled by Scan_Compiler_Arguments.
862 Scan_Compiler_Arguments
;
863 Osint
.Add_Default_Search_Dirs
;
884 Sem_Type
.Init_Interp_Tables
;
886 -- Capture compilation date and time
888 Opt
.Compilation_Time
:= System
.OS_Lib
.Current_Time_String
;
890 -- Get the target parameters only when -gnats is not used, to avoid
891 -- failing when there is no default runtime.
893 if Operating_Mode
/= Check_Syntax
then
895 -- Acquire target parameters from system.ads (package System source)
897 Targparm_Acquire
: declare
900 S
: Source_File_Index
;
904 Name_Buffer
(1 .. 10) := "system.ads";
907 S
:= Load_Source_File
(N
);
909 -- Failed to read system.ads, fatal error
911 if S
= No_Source_File
then
913 ("fatal error, run-time library not installed correctly");
914 Write_Line
("cannot locate file system.ads");
915 raise Unrecoverable_Error
;
917 -- Read system.ads successfully, remember its source index
920 System_Source_File_Index
:= S
;
923 Targparm
.Get_Target_Parameters
924 (System_Text
=> Source_Text
(S
),
925 Source_First
=> Source_First
(S
),
926 Source_Last
=> Source_Last
(S
),
927 Make_Id
=> Tbuild
.Make_Id
'Access,
928 Make_SC
=> Tbuild
.Make_SC
'Access,
929 Set_RND
=> Tbuild
.Set_RND
'Access);
931 -- Acquire configuration pragma information from Targparm
933 Restrict
.Restrictions
:= Targparm
.Restrictions_On_Target
;
934 end Targparm_Acquire
;
937 -- Perform various adjustments and settings of global switches
939 Adjust_Global_Switches
;
941 -- Output copyright notice if full list mode unless we have a list
942 -- file, in which case we defer this so that it is output in the file.
944 if (Verbose_Mode
or else (Full_List
and then Full_List_File_Name
= null))
946 -- Debug flag gnatd7 suppresses this copyright notice
948 and then not Debug_Flag_7
952 Write_Str
(Gnat_Version_String
);
954 Write_Str
("Copyright 1992-" & Current_Year
955 & ", Free Software Foundation, Inc.");
959 -- Check we do not have more than one source file, this happens only in
960 -- the case where the driver is called directly, it cannot happen when
961 -- gnat1 is invoked from gcc in the normal case.
963 if Osint
.Number_Of_Files
/= 1 then
966 Osint
.Fail
("you must provide one source file");
968 elsif Usage_Requested
then
972 -- Generate target dependent output file if requested
974 if Target_Dependent_Info_Write_Name
/= null then
975 Set_Targ
.Write_Target_Dependent_Values
;
978 -- Call the front end
980 Original_Operating_Mode
:= Operating_Mode
;
983 -- Exit with errors if the main source could not be parsed.
985 if Sinput
.Main_Source_File
= No_Source_File
then
986 Errout
.Finalize
(Last_Call
=> True);
987 Errout
.Output_Messages
;
988 Exit_Program
(E_Errors
);
991 Main_Unit_Node
:= Cunit
(Main_Unit
);
992 Main_Kind
:= Nkind
(Unit
(Main_Unit_Node
));
995 -- In CodePeer mode we always delete old SCIL files before regenerating
996 -- new ones, in case of e.g. errors, and also to remove obsolete scilx
997 -- files generated by CodePeer itself.
999 if CodePeer_Mode
then
1000 Comperr
.Delete_SCIL_Files
;
1003 -- Exit if compilation errors detected
1005 Errout
.Finalize
(Last_Call
=> False);
1007 if Compilation_Errors
then
1009 Post_Compilation_Validation_Checks
;
1010 Errout
.Output_Messages
;
1013 -- Generate ALI file if specially requested
1015 if Opt
.Force_ALI_Tree_File
then
1016 Write_ALI
(Object
=> False);
1020 Errout
.Finalize
(Last_Call
=> True);
1021 Exit_Program
(E_Errors
);
1024 -- Set Generate_Code on main unit and its spec. We do this even if are
1025 -- not generating code, since Lib-Writ uses this to determine which
1026 -- units get written in the ali file.
1028 Set_Generate_Code
(Main_Unit
);
1030 -- If we have a corresponding spec, and it comes from source or it is
1031 -- not a generated spec for a child subprogram body, then we need object
1032 -- code for the spec unit as well.
1034 if Nkind
(Unit
(Main_Unit_Node
)) in N_Unit_Body
1035 and then not Acts_As_Spec
(Main_Unit_Node
)
1037 if Nkind
(Unit
(Main_Unit_Node
)) = N_Subprogram_Body
1038 and then not Comes_From_Source
(Library_Unit
(Main_Unit_Node
))
1043 (Get_Cunit_Unit_Number
(Library_Unit
(Main_Unit_Node
)));
1047 -- Case of no code required to be generated, exit indicating no error
1049 if Original_Operating_Mode
= Check_Syntax
then
1051 Errout
.Finalize
(Last_Call
=> True);
1052 Errout
.Output_Messages
;
1057 -- Use a goto instead of calling Exit_Program so that finalization
1060 goto End_Of_Program
;
1062 elsif Original_Operating_Mode
= Check_Semantics
then
1063 Back_End_Mode
:= Declarations_Only
;
1065 -- All remaining cases are cases in which the user requested that code
1066 -- be generated (i.e. no -gnatc or -gnats switch was used). Check if we
1067 -- can in fact satisfy this request.
1069 -- Cannot generate code if someone has turned off code generation for
1070 -- any reason at all. We will try to figure out a reason below.
1072 elsif Operating_Mode
/= Generate_Code
then
1073 Back_End_Mode
:= Skip
;
1075 -- We can generate code for a subprogram body unless there were missing
1076 -- subunits. Note that we always generate code for all generic units (a
1077 -- change from some previous versions of GNAT).
1079 elsif Main_Kind
= N_Subprogram_Body
and then not Subunits_Missing
then
1080 Back_End_Mode
:= Generate_Object
;
1082 -- We can generate code for a package body unless there are subunits
1083 -- missing (note that we always generate code for generic units, which
1084 -- is a change from some earlier versions of GNAT).
1086 elsif Main_Kind
= N_Package_Body
and then not Subunits_Missing
then
1087 Back_End_Mode
:= Generate_Object
;
1089 -- We can generate code for a package declaration or a subprogram
1090 -- declaration only if it does not required a body.
1092 elsif Nkind_In
(Main_Kind
,
1093 N_Package_Declaration
,
1094 N_Subprogram_Declaration
)
1096 (not Body_Required
(Main_Unit_Node
)
1098 Distribution_Stub_Mode
= Generate_Caller_Stub_Body
)
1100 Back_End_Mode
:= Generate_Object
;
1102 -- We can generate code for a generic package declaration of a generic
1103 -- subprogram declaration only if does not require a body.
1105 elsif Nkind_In
(Main_Kind
, N_Generic_Package_Declaration
,
1106 N_Generic_Subprogram_Declaration
)
1107 and then not Body_Required
(Main_Unit_Node
)
1109 Back_End_Mode
:= Generate_Object
;
1111 -- Compilation units that are renamings do not require bodies, so we can
1112 -- generate code for them.
1114 elsif Nkind_In
(Main_Kind
, N_Package_Renaming_Declaration
,
1115 N_Subprogram_Renaming_Declaration
)
1117 Back_End_Mode
:= Generate_Object
;
1119 -- Compilation units that are generic renamings do not require bodies
1120 -- so we can generate code for them.
1122 elsif Main_Kind
in N_Generic_Renaming_Declaration
then
1123 Back_End_Mode
:= Generate_Object
;
1125 -- It is not an error to analyze in CodePeer mode a spec which requires
1126 -- a body, in order to generate SCIL for this spec.
1128 elsif CodePeer_Mode
then
1129 Back_End_Mode
:= Generate_Object
;
1131 -- It is not an error to analyze in GNATprove mode a spec which requires
1132 -- a body, when the body is not available. During frame condition
1133 -- generation, the corresponding ALI file is generated. During
1134 -- analysis, the spec is analyzed.
1136 elsif GNATprove_Mode
then
1137 Back_End_Mode
:= Declarations_Only
;
1139 -- In all other cases (specs which have bodies, generics, and bodies
1140 -- where subunits are missing), we cannot generate code and we generate
1141 -- a warning message. Note that generic instantiations are gone at this
1142 -- stage since they have been replaced by their instances.
1145 Back_End_Mode
:= Skip
;
1148 -- At this stage Back_End_Mode is set to indicate if the backend should
1149 -- be called to generate code. If it is Skip, then code generation has
1150 -- been turned off, even though code was requested by the original
1151 -- command. This is not an error from the user point of view, but it is
1152 -- an error from the point of view of the gcc driver, so we must exit
1153 -- with an error status.
1155 -- We generate an informative message (from the gcc point of view, it
1156 -- is an error message, but from the users point of view this is not an
1157 -- error, just a consequence of compiling something that cannot
1160 if Back_End_Mode
= Skip
then
1162 Write_Str
("cannot generate code for ");
1163 Write_Str
("file ");
1164 Write_Name
(Unit_File_Name
(Main_Unit
));
1166 if Subunits_Missing
then
1167 Write_Str
(" (missing subunits)");
1170 -- Force generation of ALI file, for backward compatibility
1172 Opt
.Force_ALI_Tree_File
:= True;
1174 elsif Main_Kind
= N_Subunit
then
1175 Write_Str
(" (subunit)");
1178 -- Force generation of ALI file, for backward compatibility
1180 Opt
.Force_ALI_Tree_File
:= True;
1182 elsif Main_Kind
= N_Subprogram_Declaration
then
1183 Write_Str
(" (subprogram spec)");
1186 -- Generic package body in GNAT implementation mode
1188 elsif Main_Kind
= N_Package_Body
and then GNAT_Mode
then
1189 Write_Str
(" (predefined generic)");
1192 -- Force generation of ALI file, for backward compatibility
1194 Opt
.Force_ALI_Tree_File
:= True;
1196 -- Only other case is a package spec
1199 Write_Str
(" (package spec)");
1203 Set_Standard_Output
;
1205 Post_Compilation_Validation_Checks
;
1206 Errout
.Finalize
(Last_Call
=> True);
1207 Errout
.Output_Messages
;
1211 -- Generate ALI file if specially requested, or for missing subunits,
1212 -- subunits or predefined generic.
1214 if Opt
.Force_ALI_Tree_File
then
1215 Write_ALI
(Object
=> False);
1221 -- Exit program with error indication, to kill object file
1223 Exit_Program
(E_No_Code
);
1226 -- In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
1227 -- as indicated by Back_Annotate_Rep_Info being set to True.
1229 -- We don't call for annotations on a subunit, because to process those
1230 -- the back-end requires that the parent(s) be properly compiled.
1232 -- Annotation is suppressed for targets where front-end layout is
1233 -- enabled, because the front end determines representations.
1235 -- Annotation is also suppressed in the case of compiling for a VM,
1236 -- since representations are largely symbolic there.
1238 if Back_End_Mode
= Declarations_Only
1240 (not (Back_Annotate_Rep_Info
or Generate_SCIL
or GNATprove_Mode
)
1241 or else Main_Kind
= N_Subunit
1242 or else Targparm
.Frontend_Layout_On_Target
1243 or else Targparm
.VM_Target
/= No_VM
)
1245 Post_Compilation_Validation_Checks
;
1246 Errout
.Finalize
(Last_Call
=> True);
1247 Errout
.Output_Messages
;
1248 Write_ALI
(Object
=> False);
1256 -- Ensure that we properly register a dependency on system.ads, since
1257 -- even if we do not semantically depend on this, Targparm has read
1258 -- system parameters from the system.ads file.
1260 Lib
.Writ
.Ensure_System_Dependency
;
1262 -- Add dependencies, if any, on preprocessing data file and on
1263 -- preprocessing definition file(s).
1265 Prepcomp
.Add_Dependencies
;
1267 -- In gnatprove mode we're writing the ALI much earlier than usual
1268 -- as flow analysis needs the file present in order to append its
1269 -- own globals to it.
1271 if GNATprove_Mode
then
1273 -- Note: In GNATprove mode, an "object" file is always generated as
1274 -- the result of calling gnat1 or gnat2why, although this is not the
1275 -- same as the object file produced for compilation.
1277 Write_ALI
(Object
=> True);
1280 -- Back end needs to explicitly unlock tables it needs to touch
1293 -- Here we call the back end to generate the output code
1295 Generating_Code
:= True;
1296 Back_End
.Call_Back_End
(Back_End_Mode
);
1298 -- Once the backend is complete, we unlock the names table. This call
1299 -- allows a few extra entries, needed for example for the file name for
1300 -- the library file output.
1304 -- Generate the call-graph output of dispatching calls
1306 Exp_CG
.Generate_CG_Output
;
1308 -- Perform post compilation validation checks
1310 Post_Compilation_Validation_Checks
;
1312 -- Now we complete output of errors, rep info and the tree info. These
1313 -- are delayed till now, since it is perfectly possible for gigi to
1314 -- generate errors, modify the tree (in particular by setting flags
1315 -- indicating that elaboration is required, and also to back annotate
1316 -- representation information for List_Rep_Info.
1318 Errout
.Finalize
(Last_Call
=> True);
1319 Errout
.Output_Messages
;
1320 List_Rep_Info
(Ttypes
.Bytes_Big_Endian
);
1321 Inline
.List_Inlining_Info
;
1323 -- Only write the library if the backend did not generate any error
1324 -- messages. Otherwise signal errors to the driver program so that
1325 -- there will be no attempt to generate an object file.
1327 if Compilation_Errors
then
1329 Exit_Program
(E_Errors
);
1332 if not GNATprove_Mode
then
1333 Write_ALI
(Object
=> (Back_End_Mode
= Generate_Object
));
1336 if not Compilation_Errors
then
1338 -- In case of ada backends, we need to make sure that the generated
1339 -- object file has a timestamp greater than the ALI file. We do this
1340 -- to make gnatmake happy when checking the ALI and obj timestamps,
1341 -- where it expects the object file being written after the ali file.
1343 -- Gnatmake's assumption is true for gcc platforms where the gcc
1344 -- wrapper needs to call the assembler after calling gnat1, but is
1345 -- not true for ada backends, where the object files are created
1346 -- directly by gnat1 (so are created before the ali file).
1348 Back_End
.Gen_Or_Update_Object_File
;
1351 -- Generate ASIS tree after writing the ALI file, since in ASIS mode,
1352 -- Write_ALI may in fact result in further tree decoration from the
1353 -- original tree file. Note that we dump the tree just before generating
1354 -- it, so that the dump will exactly reflect what is written out.
1359 -- Finalize name table and we are all done
1364 -- Handle fatal internal compiler errors
1366 when Rtsfind
.RE_Not_Available
=>
1367 Comperr
.Compiler_Abort
("RE_Not_Available");
1369 when System
.Assertions
.Assert_Failure
=>
1370 Comperr
.Compiler_Abort
("Assert_Failure");
1372 when Constraint_Error
=>
1373 Comperr
.Compiler_Abort
("Constraint_Error");
1375 when Program_Error
=>
1376 Comperr
.Compiler_Abort
("Program_Error");
1378 when Storage_Error
=>
1380 -- Assume this is a bug. If it is real, the message will in any case
1381 -- say Storage_Error, giving a strong hint.
1383 Comperr
.Compiler_Abort
("Storage_Error");
1389 -- The outer exception handles an unrecoverable error
1392 when Unrecoverable_Error
=>
1393 Errout
.Finalize
(Last_Call
=> True);
1394 Errout
.Output_Messages
;
1397 Write_Str
("compilation abandoned");
1400 Set_Standard_Output
;
1403 Exit_Program
(E_Errors
);