1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2005, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree
; use Atree
;
28 with Debug
; use Debug
;
29 with Einfo
; use Einfo
;
30 with Errout
; use Errout
;
31 with Fname
; use Fname
;
32 with Fname
.UF
; use Fname
.UF
;
33 with Namet
; use Namet
;
34 with Nlists
; use Nlists
;
35 with Nmake
; use Nmake
;
37 with Osint
; use Osint
;
38 with Osint
.C
; use Osint
.C
;
39 with Output
; use Output
;
41 with Restrict
; use Restrict
;
43 with Sinfo
; use Sinfo
;
44 with Sinput
; use Sinput
;
45 with Sinput
.L
; use Sinput
.L
;
46 with Stand
; use Stand
;
47 with Tbuild
; use Tbuild
;
48 with Uname
; use Uname
;
50 package body Lib
.Load
is
52 -----------------------
53 -- Local Subprograms --
54 -----------------------
56 function From_Limited_With_Chain
(Lim
: Boolean) return Boolean;
57 -- Check whether a possible circular dependence includes units that
58 -- have been loaded through limited_with clauses, in which case there
59 -- is no real circularity.
61 function Spec_Is_Irrelevant
62 (Spec_Unit
: Unit_Number_Type
;
63 Body_Unit
: Unit_Number_Type
) return Boolean;
64 -- The Spec_Unit and Body_Unit parameters are the unit numbers of the
65 -- spec file that corresponds to the main unit which is a body. This
66 -- function determines if the spec file is irrelevant and will be
67 -- overridden by the body as described in RM 10.1.4(4). See description
68 -- in "Special Handling of Subprogram Bodies" for further details.
70 procedure Write_Dependency_Chain
;
71 -- This procedure is used to generate error message info lines that
72 -- trace the current dependency chain when a load error occurs.
74 -------------------------------
75 -- Create_Dummy_Package_Unit --
76 -------------------------------
78 function Create_Dummy_Package_Unit
80 Spec_Name
: Unit_Name_Type
) return Unit_Number_Type
82 Unum
: Unit_Number_Type
;
83 Cunit_Entity
: Entity_Id
;
85 Du_Name
: Node_Or_Entity_Id
;
87 Save_CS
: constant Boolean := Get_Comes_From_Source_Default
;
90 -- The created dummy package unit does not come from source
92 Set_Comes_From_Source_Default
(False);
96 if Nkind
(Name
(With_Node
)) = N_Identifier
then
98 Make_Defining_Identifier
(No_Location
,
99 Chars
=> Chars
(Name
(With_Node
)));
100 Du_Name
:= Cunit_Entity
;
101 End_Lab
:= New_Occurrence_Of
(Cunit_Entity
, No_Location
);
107 Make_Defining_Identifier
(No_Location
,
108 Chars
=> Chars
(Selector_Name
(Name
(With_Node
))));
110 Make_Defining_Program_Unit_Name
(No_Location
,
111 Name
=> New_Copy_Tree
(Prefix
(Name
(With_Node
))),
112 Defining_Identifier
=> Cunit_Entity
);
114 Set_Is_Child_Unit
(Cunit_Entity
);
117 Make_Designator
(No_Location
,
118 Name
=> New_Copy_Tree
(Prefix
(Name
(With_Node
))),
119 Identifier
=> New_Occurrence_Of
(Cunit_Entity
, No_Location
));
122 Set_Scope
(Cunit_Entity
, Standard_Standard
);
125 Make_Compilation_Unit
(No_Location
,
126 Context_Items
=> Empty_List
,
128 Make_Package_Declaration
(No_Location
,
130 Make_Package_Specification
(No_Location
,
131 Defining_Unit_Name
=> Du_Name
,
132 Visible_Declarations
=> Empty_List
,
133 End_Label
=> End_Lab
)),
135 Make_Compilation_Unit_Aux
(No_Location
));
137 -- Mark the dummy package as analyzed to prevent analysis of this
138 -- (non-existent) unit in -gnatQ mode because at the moment the
139 -- structure and attributes of this dummy package does not allow
140 -- a normal analysis of this unit
142 Set_Analyzed
(Cunit
);
144 Units
.Increment_Last
;
147 Units
.Table
(Unum
) := (
149 Cunit_Entity
=> Cunit_Entity
,
151 Dynamic_Elab
=> False,
152 Error_Location
=> Sloc
(With_Node
),
153 Expected_Unit
=> Spec_Name
,
155 Generate_Code
=> False,
157 Ident_String
=> Empty
,
159 Main_Priority
=> Default_Main_Priority
,
162 Source_Index
=> No_Source_File
,
163 Unit_File_Name
=> Get_File_Name
(Spec_Name
, Subunit
=> False),
164 Unit_Name
=> Spec_Name
,
167 Set_Comes_From_Source_Default
(Save_CS
);
168 Set_Error_Posted
(Cunit_Entity
);
169 Set_Error_Posted
(Cunit
);
171 end Create_Dummy_Package_Unit
;
173 -----------------------------
174 -- From_Limited_With_Chain --
175 -----------------------------
177 function From_Limited_With_Chain
(Lim
: Boolean) return Boolean is
179 -- True if the current load operation is through a limited_with clause
184 -- Examine the Load_Stack to locate any previous Limited_with clause
186 elsif Load_Stack
.Last
- 1 > Load_Stack
.First
then
187 for U
in Load_Stack
.First
.. Load_Stack
.Last
- 1 loop
188 if Load_Stack
.Table
(U
).From_Limited_With
then
195 end From_Limited_With_Chain
;
201 procedure Initialize
is
207 ------------------------
208 -- Initialize_Version --
209 ------------------------
211 procedure Initialize_Version
(U
: Unit_Number_Type
) is
213 Units
.Table
(U
).Version
:= Source_Checksum
(Source_Index
(U
));
214 end Initialize_Version
;
216 ----------------------
217 -- Load_Main_Source --
218 ----------------------
220 procedure Load_Main_Source
is
221 Fname
: File_Name_Type
;
224 Load_Stack
.Increment_Last
;
225 Load_Stack
.Table
(Load_Stack
.Last
) := (Main_Unit
, False);
227 -- Initialize unit table entry for Main_Unit. Note that we don't know
228 -- the unit name yet, that gets filled in when the parser parses the
229 -- main unit, at which time a check is made that it matches the main
230 -- file name, and then the Unit_Name field is set. The Cunit and
231 -- Cunit_Entity fields also get filled in later by the parser.
233 Units
.Increment_Last
;
234 Fname
:= Next_Main_Source
;
236 Units
.Table
(Main_Unit
).Unit_File_Name
:= Fname
;
238 if Fname
/= No_File
then
239 Main_Source_File
:= Load_Source_File
(Fname
);
240 Current_Error_Source_File
:= Main_Source_File
;
242 Units
.Table
(Main_Unit
) := (
244 Cunit_Entity
=> Empty
,
246 Dynamic_Elab
=> False,
247 Error_Location
=> No_Location
,
248 Expected_Unit
=> No_Name
,
249 Fatal_Error
=> False,
250 Generate_Code
=> False,
252 Ident_String
=> Empty
,
254 Main_Priority
=> Default_Main_Priority
,
257 Source_Index
=> Main_Source_File
,
258 Unit_File_Name
=> Fname
,
259 Unit_Name
=> No_Name
,
260 Version
=> Source_Checksum
(Main_Source_File
));
262 end Load_Main_Source
;
269 (Load_Name
: Unit_Name_Type
;
271 Error_Node
: Node_Id
;
273 Corr_Body
: Unit_Number_Type
:= No_Unit
;
274 Renamings
: Boolean := False;
275 From_Limited_With
: Boolean := False) return Unit_Number_Type
277 Calling_Unit
: Unit_Number_Type
;
278 Uname_Actual
: Unit_Name_Type
;
279 Unum
: Unit_Number_Type
;
280 Unump
: Unit_Number_Type
;
281 Fname
: File_Name_Type
;
282 Src_Ind
: Source_File_Index
;
284 -- Start of processing for Load_Unit
287 -- If renamings are allowed and we have a child unit name, then we
288 -- must first load the parent to deal with finding the real name.
290 if Renamings
and then Is_Child_Name
(Load_Name
) then
293 (Load_Name
=> Get_Parent_Spec_Name
(Load_Name
),
294 Required
=> Required
,
297 Error_Node
=> Error_Node
);
299 if Unump
= No_Unit
then
303 -- If parent is a renaming, then we use the renamed package as
304 -- the actual parent for the subsequent load operation.
306 if Nkind
(Parent
(Cunit_Entity
(Unump
))) =
307 N_Package_Renaming_Declaration
312 Get_Unit_Name
(Name
(Parent
(Cunit_Entity
(Unump
)))));
314 -- Save the renaming entity, to establish its visibility when
315 -- installing the context. The implicit with is on this entity,
316 -- not on the package it renames.
318 if Nkind
(Error_Node
) = N_With_Clause
319 and then Nkind
(Name
(Error_Node
)) = N_Selected_Component
322 Par
: Node_Id
:= Name
(Error_Node
);
325 while Nkind
(Par
) = N_Selected_Component
326 and then Chars
(Selector_Name
(Par
)) /=
327 Chars
(Cunit_Entity
(Unump
))
332 -- Case of some intermediate parent is a renaming
334 if Nkind
(Par
) = N_Selected_Component
then
335 Set_Entity
(Selector_Name
(Par
), Cunit_Entity
(Unump
));
337 -- Case where the ultimate parent is a renaming
340 Set_Entity
(Par
, Cunit_Entity
(Unump
));
345 -- If the parent is not a renaming, then get its name (this may
346 -- be different from the parent spec name obtained above because
347 -- of renamings higher up in the hierarchy).
350 Uname_Actual
:= New_Child
(Load_Name
, Unit_Name
(Unump
));
353 -- Here if unit to be loaded is not a child unit
356 Uname_Actual
:= Load_Name
;
359 Fname
:= Get_File_Name
(Uname_Actual
, Subunit
);
363 Write_Str
("*** Load request for unit: ");
364 Write_Unit_Name
(Load_Name
);
367 Write_Str
(" (Required = True)");
369 Write_Str
(" (Required = False)");
374 if Uname_Actual
/= Load_Name
then
375 Write_Str
("*** Actual unit loaded: ");
376 Write_Unit_Name
(Uname_Actual
);
380 -- Capture error location if it is for the main unit. The idea is to
381 -- post errors on the main unit location, not the most recent unit.
382 -- Note: Unit_Name (Main_Unit) is not set if we are parsing gnat.adc.
384 if Present
(Error_Node
)
385 and then Unit_Name
(Main_Unit
) /= No_Name
387 -- It seems like In_Extended_Main_Source_Unit (Error_Node) would
388 -- do the trick here, but that's wrong, it is much too early to
389 -- call this routine. We are still in the parser, and the required
390 -- semantic information is not established yet. So we base the
391 -- judgment on unit names.
393 Get_External_Unit_Name_String
(Unit_Name
(Main_Unit
));
396 Main_Unit_Name
: constant String := Name_Buffer
(1 .. Name_Len
);
399 Get_External_Unit_Name_String
400 (Unit_Name
(Get_Source_Unit
(Error_Node
)));
402 -- If the two names are identical, then for sure we are part
403 -- of the extended main unit
405 if Main_Unit_Name
= Name_Buffer
(1 .. Name_Len
) then
406 Load_Msg_Sloc
:= Sloc
(Error_Node
);
408 -- If the load is called from a with_type clause, the error
411 elsif Nkind
(Parent
(Error_Node
)) = N_With_Type_Clause
then
412 Load_Msg_Sloc
:= Sloc
(Error_Node
);
414 -- Otherwise, check for the subunit case, and if so, consider
415 -- we have a match if one name is a prefix of the other name.
418 if Nkind
(Unit
(Cunit
(Main_Unit
))) = N_Subunit
420 Nkind
(Unit
(Cunit
(Get_Source_Unit
(Error_Node
)))) =
423 Name_Len
:= Integer'Min (Name_Len
, Main_Unit_Name
'Length);
425 if Name_Buffer
(1 .. Name_Len
)
427 Main_Unit_Name
(1 .. Name_Len
)
429 Load_Msg_Sloc
:= Sloc
(Error_Node
);
436 -- If we are generating error messages, then capture calling unit
438 if Present
(Error_Node
) then
439 Calling_Unit
:= Get_Source_Unit
(Error_Node
);
441 Calling_Unit
:= No_Unit
;
444 -- See if we already have an entry for this unit
448 while Unum
<= Units
.Last
loop
449 exit when Uname_Actual
= Units
.Table
(Unum
).Unit_Name
;
453 -- Whether or not the entry was found, Unum is now the right value,
454 -- since it is one more than Units.Last (i.e. the index of the new
455 -- entry we will create) in the not found case.
457 -- A special check is necessary in the unit not found case. If the unit
458 -- is not found, but the file in which it lives has already been loaded,
459 -- then we have the problem that the file does not contain the unit that
460 -- is needed. We simply treat this as a file not found condition.
462 -- We skip this test in multiple unit per file mode since in this
463 -- case we can have multiple units from the same source file.
465 if Unum
> Units
.Last
and then Multiple_Unit_Index
= 0 then
466 for J
in Units
.First
.. Units
.Last
loop
467 if Fname
= Units
.Table
(J
).Unit_File_Name
then
469 Write_Str
(" file does not contain unit, Unit_Number = ");
470 Write_Int
(Int
(Unum
));
475 if Present
(Error_Node
) then
476 if Is_Predefined_File_Name
(Fname
) then
477 Error_Msg_Name_1
:= Uname_Actual
;
479 ("% is not a language defined unit", Load_Msg_Sloc
);
481 Error_Msg_Name_1
:= Fname
;
482 Error_Msg_Unit_1
:= Uname_Actual
;
484 ("File{ does not contain unit$", Load_Msg_Sloc
);
487 Write_Dependency_Chain
;
497 -- If we are proceeding with load, then make load stack entry,
498 -- and indicate the kind of with_clause responsible for the load.
500 Load_Stack
.Increment_Last
;
501 Load_Stack
.Table
(Load_Stack
.Last
) := (Unum
, From_Limited_With
);
503 -- Case of entry already in table
505 if Unum
<= Units
.Last
then
507 -- Here is where we check for a circular dependency, which is
508 -- an attempt to load a unit which is currently in the process
509 -- of being loaded. We do *not* care about a circular chain that
510 -- leads back to a body, because this kind of circular dependence
511 -- legitimately occurs (e.g. two package bodies that contain
512 -- inlined subprogram referenced by the other).
514 -- Ada 2005 (AI-50217): We also ignore limited_with clauses, because
515 -- their purpose is precisely to create legal circular structures.
518 and then (Is_Spec_Name
(Units
.Table
(Unum
).Unit_Name
)
519 or else Acts_As_Spec
(Units
.Table
(Unum
).Cunit
))
520 and then (Nkind
(Error_Node
) /= N_With_Clause
521 or else not Limited_Present
(Error_Node
))
522 and then not From_Limited_With_Chain
(From_Limited_With
)
525 Write_Str
(" circular dependency encountered");
529 if Present
(Error_Node
) then
530 Error_Msg
("circular unit dependency", Load_Msg_Sloc
);
531 Write_Dependency_Chain
;
533 Load_Stack
.Decrement_Last
;
540 Write_Str
(" unit already in file table, Unit_Number = ");
541 Write_Int
(Int
(Unum
));
545 Load_Stack
.Decrement_Last
;
548 -- Unit is not already in table, so try to open the file
552 Write_Str
(" attempt unit load, Unit_Number = ");
553 Write_Int
(Int
(Unum
));
557 Src_Ind
:= Load_Source_File
(Fname
);
559 -- Make a partial entry in the file table, used even in the file not
560 -- found case to print the dependency chain including the last entry
562 Units
.Increment_Last
;
563 Units
.Table
(Unum
).Unit_Name
:= Uname_Actual
;
567 if Src_Ind
/= No_Source_File
then
568 Units
.Table
(Unum
) := (
570 Cunit_Entity
=> Empty
,
572 Dynamic_Elab
=> False,
573 Error_Location
=> Sloc
(Error_Node
),
574 Expected_Unit
=> Uname_Actual
,
575 Fatal_Error
=> False,
576 Generate_Code
=> False,
578 Ident_String
=> Empty
,
580 Main_Priority
=> Default_Main_Priority
,
583 Source_Index
=> Src_Ind
,
584 Unit_File_Name
=> Fname
,
585 Unit_Name
=> Uname_Actual
,
586 Version
=> Source_Checksum
(Src_Ind
));
588 -- Parse the new unit
591 Save_Index
: constant Nat
:= Multiple_Unit_Index
;
593 Multiple_Unit_Index
:= Get_Unit_Index
(Uname_Actual
);
594 Units
.Table
(Unum
).Munit_Index
:= Multiple_Unit_Index
;
595 Initialize_Scanner
(Unum
, Source_Index
(Unum
));
596 Discard_List
(Par
(Configuration_Pragmas
=> False,
597 From_Limited_With
=> From_Limited_With
));
598 Multiple_Unit_Index
:= Save_Index
;
599 Set_Loading
(Unum
, False);
602 -- If spec is irrelevant, then post errors and quit
604 if Corr_Body
/= No_Unit
605 and then Spec_Is_Irrelevant
(Unum
, Corr_Body
)
607 Error_Msg_Name_1
:= Unit_File_Name
(Corr_Body
);
609 ("cannot compile subprogram in file {!",
611 Error_Msg_Name_1
:= Unit_File_Name
(Unum
);
613 ("incorrect spec in file { must be removed first!",
618 -- If loaded unit had a fatal error, then caller inherits it!
620 if Units
.Table
(Unum
).Fatal_Error
621 and then Present
(Error_Node
)
623 Units
.Table
(Calling_Unit
).Fatal_Error
:= True;
626 -- Remove load stack entry and return the entry in the file table
628 Load_Stack
.Decrement_Last
;
631 -- Case of file not found
635 Write_Str
(" file was not found, load failed");
639 -- Generate message if unit required
641 if Required
and then Present
(Error_Node
) then
642 if Is_Predefined_File_Name
(Fname
) then
644 -- This is a predefined library unit which is not present
645 -- in the run time. If a predefined unit is not available
646 -- it may very likely be the case that there is also pragma
647 -- Restriction forbidding its usage. This is typically the
648 -- case when building a configurable run time, where the
649 -- usage of certain run-time units units is restricted by
650 -- means of both the corresponding pragma Restriction (such
651 -- as No_Calendar), and by not including the unit. Hence,
652 -- we check whether this predefined unit is forbidden, so
653 -- that the message about the restriction violation is
654 -- generated, if needed.
656 Check_Restricted_Unit
(Load_Name
, Error_Node
);
658 Error_Msg_Name_1
:= Uname_Actual
;
660 ("% is not a predefined library unit", Load_Msg_Sloc
);
663 Error_Msg_Name_1
:= Fname
;
664 Error_Msg
("file{ not found", Load_Msg_Sloc
);
667 Write_Dependency_Chain
;
669 -- Remove unit from stack, to avoid cascaded errors on
670 -- subsequent missing files.
672 Load_Stack
.Decrement_Last
;
673 Units
.Decrement_Last
;
675 -- If unit not required, remove load stack entry and the junk
676 -- file table entry, and return No_Unit to indicate not found,
679 Load_Stack
.Decrement_Last
;
680 Units
.Decrement_Last
;
688 ------------------------
689 -- Make_Instance_Unit --
690 ------------------------
692 -- If the unit is an instance, it appears as a package declaration, but
693 -- contains both declaration and body of the instance. The body becomes
694 -- the main unit of the compilation, and the declaration is inserted
695 -- at the end of the unit table. The main unit now has the name of a
696 -- body, which is constructed from the name of the original spec,
697 -- and is attached to the compilation node of the original unit. The
698 -- declaration has been attached to a new compilation unit node, and
699 -- code will have to be generated for it.
701 procedure Make_Instance_Unit
(N
: Node_Id
) is
702 Sind
: constant Source_File_Index
:= Source_Index
(Main_Unit
);
704 Units
.Increment_Last
;
705 Units
.Table
(Units
.Last
) := Units
.Table
(Main_Unit
);
706 Units
.Table
(Units
.Last
).Cunit
:= Library_Unit
(N
);
707 Units
.Table
(Units
.Last
).Generate_Code
:= True;
708 Units
.Table
(Main_Unit
).Cunit
:= N
;
709 Units
.Table
(Main_Unit
).Unit_Name
:=
710 Get_Body_Name
(Unit_Name
(Get_Cunit_Unit_Number
(Library_Unit
(N
))));
711 Units
.Table
(Main_Unit
).Version
:= Source_Checksum
(Sind
);
712 end Make_Instance_Unit
;
714 ------------------------
715 -- Spec_Is_Irrelevant --
716 ------------------------
718 function Spec_Is_Irrelevant
719 (Spec_Unit
: Unit_Number_Type
;
720 Body_Unit
: Unit_Number_Type
) return Boolean
722 Sunit
: constant Node_Id
:= Cunit
(Spec_Unit
);
723 Bunit
: constant Node_Id
:= Cunit
(Body_Unit
);
726 -- The spec is irrelevant if the body is a subprogram body, and the
727 -- spec is other than a subprogram spec or generic subprogram spec.
728 -- Note that the names must be the same, we don't need to check that,
729 -- because we already know that from the fact that the file names are
733 Nkind
(Unit
(Bunit
)) = N_Subprogram_Body
734 and then Nkind
(Unit
(Sunit
)) /= N_Subprogram_Declaration
735 and then Nkind
(Unit
(Sunit
)) /= N_Generic_Subprogram_Declaration
;
736 end Spec_Is_Irrelevant
;
742 procedure Version_Update
(U
: Node_Id
; From
: Node_Id
) is
743 Unum
: constant Unit_Number_Type
:= Get_Cunit_Unit_Number
(U
);
744 Fnum
: constant Unit_Number_Type
:= Get_Cunit_Unit_Number
(From
);
746 if Source_Index
(Fnum
) /= No_Source_File
then
747 Units
.Table
(Unum
).Version
:=
748 Units
.Table
(Unum
).Version
750 Source_Checksum
(Source_Index
(Fnum
));
754 ----------------------------
755 -- Write_Dependency_Chain --
756 ----------------------------
758 procedure Write_Dependency_Chain
is
760 -- The dependency chain is only written if it is at least two entries
761 -- deep, otherwise it is trivial (the main unit depending on a unit
762 -- that it obviously directly depends on).
764 if Load_Stack
.Last
- 1 > Load_Stack
.First
then
765 for U
in Load_Stack
.First
.. Load_Stack
.Last
- 1 loop
767 Unit_Name
(Load_Stack
.Table
(U
).Unit_Number
);
769 Unit_Name
(Load_Stack
.Table
(U
+ 1).Unit_Number
);
770 Error_Msg
("$ depends on $!", Load_Msg_Sloc
);
773 end Write_Dependency_Chain
;