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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S E M _ C H 1 0 --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
10 -- --
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. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
70 -----------------------
71 -- Local Subprograms --
72 -----------------------
75 -- Analyzes items in the context clause of compilation unit
78 -- Build and decorate the list of shadow entities for a package mentioned
79 -- in a limited_with clause. If the package was not previously analyzed
80 -- then it also performs a basic decoration of the real entities. This is
81 -- required to do not pass non-decorated entities to the back-end.
82 -- Implements Ada 2005 (AI-50217).
85 -- Check whether the source for the body of a compilation unit must be
86 -- included in a standalone library.
89 -- If a with_clause mentions a private child unit, the compilation
90 -- unit must be a member of the same family, as described in 10.1.2.
93 -- Verify that a stub is declared immediately within a compilation unit,
94 -- and not in an inner frame.
97 -- When a child unit appears in a context clause, the implicit withs on
98 -- parents are made explicit, and with clauses are inserted in the context
99 -- clause before the one for the child. If a parent in the with_clause
100 -- is a renaming, the implicit with_clause is on the renaming whose name
101 -- is mentioned in the with_clause, and not on the package it renames.
102 -- N is the compilation unit whose list of context items receives the
103 -- implicit with_clauses.
106 -- Get defining entity of parent unit of a child unit. In most cases this
107 -- is the defining entity of the unit, but for a child instance whose
108 -- parent needs a body for inlining, the instantiation node of the parent
109 -- has not yet been rewritten as a package declaration, and the entity has
110 -- to be retrieved from the Instance_Spec of the unit.
112 function Has_With_Clause
116 -- Determine whether compilation unit C_Unit contains a [limited] with
117 -- clause for package Pack. Use the flag Is_Limited to designate desired
118 -- clause kind.
121 -- If the main unit is a child unit, implicit withs are also added for
122 -- all its ancestors.
125 -- Check that the shadow entity is not already in the homonym chain, for
126 -- example through a limited_with clause in a parent unit.
129 -- Subsidiary to Install_Context and Install_Parents. Process only with_
130 -- and use_clauses for current unit and its library unit if any.
133 -- Subsidiary to Install_Context. Process only limited with_clauses for
134 -- current unit. Implements Ada 2005 (AI-50217).
137 -- Place shadow entities for a limited_with package in the visibility
138 -- structures for the current compilation. Implements Ada 2005 (AI-50217).
140 procedure Install_Withed_Unit
143 -- If the unit is not a child unit, make unit immediately visible. The
144 -- caller ensures that the unit is not already currently installed. The
145 -- flag Private_With_OK is set true in Install_Private_With_Clauses, which
146 -- is called when compiling the private part of a package, or installing
147 -- the private declarations of a parent unit.
150 -- This procedure establishes the context for the compilation of a child
151 -- unit. If Lib_Unit is a child library spec then the context of the parent
152 -- is installed, and the parent itself made immediately visible, so that
153 -- the child unit is processed in the declarative region of the parent.
154 -- Install_Parents makes a recursive call to itself to ensure that all
155 -- parents are loaded in the nested case. If Lib_Unit is a library body,
156 -- the only effect of Install_Parents is to install the private decls of
157 -- the parents, because the visible parent declarations will have been
158 -- installed as part of the context of the corresponding spec.
161 -- In the compilation of a child unit, a child of any of the ancestor
162 -- units is directly visible if it is visible, because the parent is in
163 -- an enclosing scope. Iterate over context to find child units of U_Name
164 -- or of some ancestor of it.
167 -- Lib_Unit is a library unit which may be a spec or a body. Is_Child_Spec
168 -- returns True if Lib_Unit is a library spec which is a child spec, i.e.
169 -- a library spec that has a parent. If the call to Is_Child_Spec returns
170 -- True, then Parent_Spec (Lib_Unit) is non-Empty and points to the
171 -- compilation unit for the parent spec.
172 --
173 -- Lib_Unit can also be a subprogram body that acts as its own spec. If the
174 -- Parent_Spec is non-empty, this is also a child unit.
177 -- Subsidiary of previous one. Remove use_ and with_clauses
180 -- Remove from visibility the shadow entities introduced for a package
181 -- mentioned in a limited_with clause. Implements Ada 2005 (AI-50217).
184 -- Remove_Parents checks if Lib_Unit is a child spec. If so then the parent
185 -- contexts established by the corresponding call to Install_Parents are
186 -- removed. Remove_Parents contains a recursive call to itself to ensure
187 -- that all parents are removed in the nested case.
190 -- Reset all visibility flags on unit after compiling it, either as a
191 -- main unit or as a unit in the context.
194 -- Remove single entity from visibility list
197 -- Common processing for all stubs (subprograms, tasks, packages, and
198 -- protected cases). N is the stub to be analyzed. Once the subunit
199 -- name is established, load and analyze. Nam is the non-overloadable
200 -- entity for which the proper body provides a completion. Subprogram
201 -- stubs are handled differently because they can be declarations.
204 -- A dummy procedure, for debugging use, called just before analyzing the
205 -- main unit (after dealing with any context clauses).
207 --------------------------
208 -- Limited_With_Clauses --
209 --------------------------
211 -- Limited_With clauses are the mechanism chosen for Ada05 to support
212 -- mutually recursive types declared in different units. A limited_with
213 -- clause that names package P in the context of unit U makes the types
214 -- declared in the visible part of P available within U, but with the
215 -- restriction that these types can only be used as incomplete types.
216 -- The limited_with clause does not impose a semantic dependence on P,
217 -- and it is possible for two packages to have limited_with_clauses on
218 -- each other without creating an elaboration circularity.
220 -- To support this feature, the analysis of a limited_with clause must
221 -- create an abbreviated view of the package, without performing any
222 -- semantic analysis on it. This "package abstract" contains shadow types
223 -- that are in one-one correspondence with the real types in the package,
224 -- and that have the properties of incomplete types.
226 -- The implementation creates two element lists: one to chain the shadow
227 -- entities, and one to chain the corresponding type entities in the tree
228 -- of the package. Links between corresponding entities in both chains
229 -- allow the compiler to select the proper view of a given type, depending
230 -- on the context. Note that in contrast with the handling of private
231 -- types, the limited view and the non-limited view of a type are treated
232 -- as separate entities, and no entity exchange needs to take place, which
233 -- makes the implementation must simpler than could be feared.
235 ------------------------------
236 -- Analyze_Compilation_Unit --
237 ------------------------------
247 procedure Check_Redundant_Withs
250 -- Determine whether the context list of a compilation unit contains
251 -- redundant with clauses. When checking body clauses against spec
252 -- clauses, set Context_Items to the context list of the body and
253 -- Spec_Context_Items to that of the spec. Parent packages are not
254 -- examined for documentation purposes.
257 -- Generate cross-reference information for the parents of child units.
258 -- N is a defining_program_unit_name, and P_Id is the immediate parent.
260 ---------------------------
261 -- Check_Redundant_Withs --
262 ---------------------------
264 procedure Check_Redundant_Withs
267 is
270 procedure Process_Body_Clauses
275 -- Examine the context clauses of a package body, trying to match
276 -- the name entity of Clause with any list element. If the match
277 -- occurs on a use package clause, set Used to True, for a use
278 -- type clause, pragma Elaborate or pragma Elaborate_All, set
279 -- Used_Type_Or_Elab to True.
281 procedure Process_Spec_Clauses
287 -- Examine the context clauses of a package spec, trying to match
288 -- the name entity of Clause with any list element. If the match
289 -- occurs on a use package clause, set Used to True, for a with
290 -- package clause other than Clause, set Withed to True. Limited
291 -- with clauses, implicitly generated with clauses and withs
292 -- having pragmas Elaborate or Elaborate_All applied to them are
293 -- skipped. Exit_On_Self is used to control the search loop and
294 -- force an exit whenever Clause sees itself in the search.
296 --------------------------
297 -- Process_Body_Clauses --
298 --------------------------
300 procedure Process_Body_Clauses
305 is
313 -- In an expanded name in a use clause, if the prefix is a renamed
314 -- package, the entity is set to the original package as a result,
315 -- when checking whether the package appears in a previous with
316 -- clause, the renaming has to be taken into account, to prevent
317 -- spurious/incorrect warnings. A common case is use of Text_IO.
319 ---------------
320 -- Same_Unit --
321 ---------------
324 begin
326 or else
331 -- Start of processing for Process_Body_Clauses
333 begin
340 -- Package use clause
343 and then not Used
344 then
345 -- Search through use clauses
350 -- Case of a direct use of the one we are looking for
355 -- Handle nested case, as in "with P; use P.Q.R"
357 else
358 declare
361 begin
362 -- Loop through prefixes looking for match
379 -- USE TYPE clause
382 and then not Used_Type_Or_Elab
383 then
386 and then not Used_Type_Or_Elab
387 loop
395 -- Pragma Elaborate or Elaborate_All
398 and then
400 or else
402 and then not Used_Type_Or_Elab
403 then
404 Prag_Unit :=
407 and then not Used_Type_Or_Elab
408 loop
421 --------------------------
422 -- Process_Spec_Clauses --
423 --------------------------
425 procedure Process_Spec_Clauses
431 is
436 begin
443 -- Stop the search since the context items after Cont_Item have
444 -- already been examined in a previous iteration of the reverse
445 -- loop in Check_Redundant_Withs.
447 if Exit_On_Self
449 then
453 -- Package use clause
456 and then not Used
457 then
467 -- Package with clause. Avoid processing self, implicitly
468 -- generated with clauses or limited with clauses. Note that
469 -- we examine with clauses having pragmas Elaborate or
470 -- Elaborate_All applied to them due to cases such as:
471 --
473 -- with Pack;
474 -- with Pack;
475 -- pragma Elaborate (Pack);
476 --
477 -- In this case, the second with clause is redundant since
478 -- the pragma applies only to the first "with Pack;".
485 then
493 -- Start of processing for Check_Redundant_Withs
495 begin
499 -- Avoid checking implicitly generated with clauses, limited with
500 -- clauses or withs that have pragma Elaborate or Elaborate_All.
506 then
507 -- Package body-to-spec check
510 declare
516 begin
517 Process_Spec_Clauses
523 Process_Body_Clauses
529 -- "Type Elab" refers to the presence of either a use
530 -- type clause, pragmas Elaborate or Elaborate_All.
532 -- +---------------+---------------------------+------+
533 -- | Spec | Body | Warn |
534 -- +--------+------+--------+------+-----------+------+
535 -- | Withed | Used | Withed | Used | Type Elab | |
536 -- | X | | X | | | X |
537 -- | X | | X | X | | |
538 -- | X | | X | | X | |
539 -- | X | | X | X | X | |
540 -- | X | X | X | | | X |
541 -- | X | X | X | | X | |
542 -- | X | X | X | X | | X |
543 -- | X | X | X | X | X | |
544 -- +--------+------+--------+------+-----------+------+
548 and then
551 or else
552 Used_In_Spec)
553 then
554 Error_Msg_N -- CODEFIX
564 -- Standalone package spec or body check
566 else
567 declare
571 begin
572 -- The mechanism for examining the context clauses of a
573 -- package spec can be applied to package body clauses.
575 Process_Spec_Clauses
583 Error_Msg_N -- CODEFIX
594 --------------------------------
595 -- Generate_Parent_References --
596 --------------------------------
602 begin
607 -- Done already, if the unit has been compiled indirectly as
608 -- part of the closure of its context because of inlining.
622 -- The guard here on P_Name is to handle the error condition where
623 -- the parent unit is missing because the file was not found.
633 -- Start of processing for Analyze_Compilation_Unit
635 begin
638 -- If the unit is a subunit whose parent has not been analyzed (which
639 -- indicates that the main unit is a subunit, either the current one or
640 -- one of its descendents) then the subunit is compiled as part of the
641 -- analysis of the parent, which we proceed to do. Basically this gets
642 -- handled from the top down and we don't want to do anything at this
643 -- level (i.e. this subunit will be handled on the way down from the
644 -- parent), so at this level we immediately return. If the subunit ends
645 -- up not analyzed, it means that the parent did not contain a stub for
646 -- it, or that there errors were detected in some ancestor.
650 then
656 else
664 -- Analyze context (this will call Sem recursively for with'ed units) To
665 -- detect circularities among with-clauses that are not caught during
666 -- loading, we set the Context_Pending flag on the current unit. If the
667 -- flag is already set there is a potential circularity. We exclude
668 -- predefined units from this check because they are known to be safe.
669 -- We also exclude package bodies that are present because circularities
670 -- between bodies are harmless (and necessary).
673 declare
676 begin
677 if Is_Predefined_File_Name
679 then
682 else
686 then
695 Error_Msg_N
709 else
717 -- If the unit is a package body, the spec is already loaded and must be
718 -- analyzed first, before we analyze the body.
722 -- If no Lib_Unit, then there was a serious previous error, so just
723 -- ignore the entire analysis effort
728 else
732 -- Verify that the library unit is a package declaration
735 N_Generic_Package_Declaration)
736 then
737 Error_Msg_N
741 -- Otherwise, the entity in the declaration is visible. Update the
742 -- version to reflect dependence of this body on the spec.
744 else
750 N_Defining_Program_Unit_Name
751 then
757 -- If the unit is a subprogram body, then we similarly need to analyze
758 -- its spec. However, things are a little simpler in this case, because
759 -- here, this analysis is done only for error checking and consistency
760 -- purposes, so there's nothing else to be done.
765 -- If the subprogram body is a child unit, we must create a
766 -- declaration for it, in order to properly load the parent(s).
767 -- After this, the original unit does not acts as a spec, because
768 -- there is an explicit one. If this unit appears in a context
769 -- clause, then an implicit with on the parent will be added when
770 -- installing the context. If this is the main unit, there is no
771 -- Unit_Table entry for the declaration (it has the unit number
772 -- of the main unit) and code generation is unaffected.
778 Unum :=
779 Load_Unit
787 -- Build subprogram declaration and attach parent unit to it
788 -- This subprogram declaration does not come from source,
789 -- Nevertheless the backend must generate debugging info for
790 -- it, and this must be indicated explicitly. We also mark
791 -- the body entity as a child unit now, to prevent a
792 -- cascaded error if the spec entity cannot be entered
793 -- in its scope. Finally we create a Units table entry for
794 -- the subprogram declaration, to maintain a one-to-one
795 -- correspondence with compilation unit nodes. This is
796 -- critical for the tree traversals performed by CodePeer.
798 declare
801 Get_Comes_From_Source_Default;
803 begin
805 Lib_Unit :=
808 Unit =>
810 Specification =>
811 Copy_Separate_Tree
813 Aux_Decls_Node =>
821 -- Now that a separate declaration exists, the body
822 -- of the child unit does not act as spec any longer.
832 -- Here for subprogram with separate declaration
834 else
840 -- If this is a child unit, generate references to the parents
843 N_Defining_Program_Unit_Name
844 then
845 Generate_Parent_References (
851 -- If it is a child unit, the parent must be elaborated first and we
852 -- update version, since we are dependent on our parent.
856 -- The analysis of the parent is done with style checks off
858 declare
861 Cunit_Boolean_Restrictions_Save;
863 begin
875 -- With the analysis done, install the context. Note that we can't
876 -- install the context from the with clauses as we analyze them, because
877 -- each with clause must be analyzed in a clean visibility context, so
878 -- we have to wait and install them all at once.
884 -- Set the entities of all parents in the program_unit_name
886 Generate_Parent_References (
890 -- All components of the context: with-clauses, library unit, ancestors
891 -- if any, (and their context) are analyzed and installed.
893 -- Call special debug routine sm if this is the main unit
896 sm;
899 -- Now analyze the unit (package, subprogram spec, body) itself
907 Check_Redundant_Withs
913 -- The above call might have made Unit_Node an N_Subprogram_Body from
914 -- something else, so propagate any Acts_As_Spec flag.
918 then
922 -- Register predefined units in Rtsfind
924 declare
926 begin
932 -- Treat compilation unit pragmas that appear after the library unit
935 declare
937 begin
945 -- Generate distribution stubs if requested and no error
949 or else
952 then
955 -- Regular RCI package
963 and then
965 then
966 -- Shared passive package
971 and then
972 Is_Remote_Call_Interface
974 then
975 -- Instantiation of a RCI generic package
981 -- Remove unit from visibility, so that environment is clean for the
982 -- next compilation, which is either the main unit or some other unit
983 -- in the context.
986 N_Package_Renaming_Declaration,
987 N_Subprogram_Declaration)
989 or else
992 then
995 -- If the unit is an instantiation whose body will be elaborated for
996 -- inlining purposes, use the proper entity of the instance. The entity
997 -- may be missing if the instantiation was illegal.
1002 then
1003 Remove_Unit_From_Visibility
1009 then
1010 -- Bodies that are not the main unit are compiled if they are generic
1011 -- or contain generic or inlined units. Their analysis brings in the
1012 -- context of the corresponding spec (unit declaration) which must be
1013 -- removed as well, to return the compilation environment to its
1014 -- proper state.
1020 -- Last step is to deinstall the context we just installed as well as
1021 -- the unit just compiled.
1025 -- If this is the main unit and we are generating code, we must check
1026 -- that all generic units in the context have a body if they need it,
1027 -- even if they have not been instantiated. In the absence of .ali files
1028 -- for generic units, we must force the load of the body, just to
1029 -- produce the proper error if the body is absent. We skip this
1030 -- verification if the main unit itself is generic.
1034 and then Expander_Active
1035 then
1036 -- Check whether the source for the body of the unit must be included
1037 -- in a standalone library.
1041 -- Indicate that the main unit is now analyzed, to catch possible
1042 -- circularities between it and generic bodies. Remove main unit from
1043 -- visibility. This might seem superfluous, but the main unit must
1044 -- not be visible in the generic body expansions that follow.
1049 declare
1056 Cunit_Boolean_Restrictions_Save;
1058 begin
1062 -- Check for explicit with clause
1067 -- Ada 2005 (AI-50217): Ignore limited-withed units
1070 then
1073 -- Compile generic subprogram, unless it is intrinsic or
1074 -- imported so no body is required, or generic package body
1075 -- if the package spec requires a body.
1082 then
1086 Un :=
1087 Load_Unit
1089 (Get_Unit_Name
1090 (Unit_Declaration_Node
1096 else
1097 Un :=
1098 Load_Unit
1108 Error_Msg_NE
1115 then
1130 -- Deal with creating elaboration Boolean if needed. We create an
1131 -- elaboration boolean only for units that come from source since
1132 -- units manufactured by the compiler never need elab checks.
1136 N_Generic_Package_Declaration,
1137 N_Subprogram_Declaration,
1138 N_Generic_Subprogram_Declaration)
1139 then
1140 declare
1144 begin
1148 -- See if an elaboration entity is required for possible access
1149 -- before elaboration checking. Note that we must allow for this
1150 -- even if -gnatE is not set, since a client may be compiled in
1151 -- -gnatE mode and reference the entity.
1153 -- These entities are also used by the binder to prevent multiple
1154 -- attempts to execute the elaboration code for the library case
1155 -- where the elaboration routine might otherwise be called more
1156 -- than once.
1158 -- Case of units which do not require elaboration checks
1160 if
1161 -- Pure units do not need checks
1165 -- Preelaborated units do not need checks
1169 -- No checks needed if pragma Elaborate_Body present
1173 -- No checks needed if unit does not require a body
1177 -- No checks needed for predefined files
1181 -- No checks required if no separate spec
1184 then
1185 -- This is a case where we only need the entity for
1186 -- checking to prevent multiple elaboration checks.
1190 -- Case of elaboration entity is required for access before
1191 -- elaboration checking (so certainly we must build it!)
1193 else
1201 -- Freeze the compilation unit entity. This for sure is needed because
1202 -- of some warnings that can be output (see Freeze_Subprogram), but may
1203 -- in general be required. If freezing actions result, place them in the
1204 -- compilation unit actions list, and analyze them.
1206 declare
1210 begin
1220 and then Expander_Active
1221 then
1222 declare
1227 begin
1229 Reset_Style_Check_Options;
1233 Reset_Style_Check_Options;
1240 -- If we are generating obsolescent warnings, then here is where we
1241 -- generate them for the with'ed items. The reason for this special
1242 -- processing is that the normal mechanism of generating the warnings
1243 -- for referenced entities does not work for context clause references.
1244 -- That's because when we first analyze the context, it is too early to
1245 -- know if the with'ing unit is itself obsolescent (which suppresses
1246 -- the warnings).
1250 -- Push current compilation unit as scope, so that the test for
1251 -- being within an obsolescent unit will work correctly.
1255 -- Loop through context items to deal with with clauses
1257 declare
1262 begin
1267 -- Suppress this check in limited-withed units. Further work
1268 -- needed here if we decide to incorporate this check on
1269 -- limited-withed units.
1272 then
1285 -- Remove temporary install of current unit as scope
1287 Pop_Scope;
1291 ---------------------
1292 -- Analyze_Context --
1293 ---------------------
1299 begin
1300 -- First process all configuration pragmas at the start of the context
1301 -- items. Strictly these are not part of the context clause, but that
1302 -- is where the parser puts them. In any case for sure we must analyze
1303 -- these before analyzing the actual context items, since they can have
1304 -- an effect on that analysis (e.g. pragma Ada_2005 may allow a unit to
1305 -- be with'ed as a result of changing categorizations in Ada 2005).
1311 loop
1316 -- This is the point at which we capture the configuration settings
1317 -- for the unit. At the moment only the Optimize_Alignment setting
1318 -- needs to be captured. Probably more later ???
1322 else
1326 -- Loop through actual context items. This is done in two passes:
1328 -- a) The first pass analyzes non-limited with-clauses and also any
1329 -- configuration pragmas (we need to get the latter analyzed right
1330 -- away, since they can affect processing of subsequent items.
1332 -- b) The second pass analyzes limited_with clauses (Ada 2005: AI-50217)
1336 -- For with clause, analyze the with clause, and then update the
1337 -- version, since we are dependent on a unit that we with.
1341 then
1342 -- Skip analyzing with clause if no unit, nothing to do (this
1343 -- happens for a with that references a non-existent unit). Skip
1344 -- as well if this is a with_clause for the main unit, which
1345 -- happens if a subunit has a useless with_clause on its parent.
1351 else
1360 -- Skip pragmas. Configuration pragmas at the start were handled in
1361 -- the loop above, and remaining pragmas are not processed until we
1362 -- actually install the context (see Install_Context). We delay the
1363 -- analysis of these pragmas to make sure that we have installed all
1364 -- the implicit with's on parent units.
1366 -- Skip use clauses at this stage, since we don't want to do any
1367 -- installing of potentially use-visible entities until we
1368 -- actually install the complete context (in Install_Context).
1369 -- Otherwise things can get installed in the wrong context.
1371 else
1378 -- Second pass: examine all limited_with clauses. All other context
1379 -- items are ignored in this pass.
1385 then
1386 -- No need to check errors on implicitly generated limited-with
1387 -- clauses.
1391 -- Verify that the illegal contexts given in 10.1.2 (18/2) are
1392 -- properly rejected, including renaming declarations.
1395 N_Subprogram_Declaration)
1398 then
1401 -- Check wrong use of a limited with clause applied to the
1402 -- compilation unit containing the limited-with clause.
1404 -- limited with P.Q;
1405 -- package P.Q is ...
1410 -- Check wrong use of limited-with clause applied to some
1411 -- immediate ancestor.
1414 declare
1418 begin
1420 loop
1433 -- Check if the limited-withed unit is already visible through
1434 -- some context clause of the current compilation unit or some
1435 -- ancestor of the current compilation unit.
1437 declare
1443 begin
1445 loop
1451 and then
1453 N_Package_Declaration,
1454 N_Package_Renaming_Declaration)
1455 then
1457 N_Package_Declaration
1458 then
1460 else
1464 -- Check if the named package (or some ancestor)
1465 -- leaves visible the full-view of the unit given
1466 -- in the limited-with clause
1468 loop
1470 Unit_Name)
1471 then
1473 Error_Msg_N
1476 Item);
1477 Error_Msg_NE
1501 -- Skip analyzing with clause if no unit, see above
1507 -- A limited_with does not impose an elaboration order, but
1508 -- there is a semantic dependency for recompilation purposes.
1514 -- Pragmas and use clauses and with clauses other than limited
1515 -- with's are ignored in this pass through the context items.
1517 else
1525 -------------------------------
1526 -- Analyze_Package_Body_Stub --
1527 -------------------------------
1533 begin
1534 -- The package declaration must be in the current declarative part
1544 then
1547 else
1548 -- Indicate that the body of the package exists. If we are doing
1549 -- only semantic analysis, the stub stands for the body. If we are
1550 -- generating code, the existence of the body will be confirmed
1551 -- when we load the proper body.
1560 -------------------------
1561 -- Analyze_Proper_Body --
1562 -------------------------
1569 -- This procedure is called when the main unit is a stub, or when we
1570 -- are not generating code. In such a case, we analyze the subunit if
1571 -- present, which is user-friendly and in fact required for ASIS, but
1572 -- we don't complain if the subunit is missing.
1574 ----------------------
1575 -- Optional_Subunit --
1576 ----------------------
1581 begin
1582 -- Try to load subunit, but ignore any errors that occur during the
1583 -- loading of the subunit, by using the special feature in Errout to
1584 -- ignore all errors. Note that Fatal_Error will still be set, so we
1585 -- will be able to check for this case below.
1591 Unum :=
1592 Load_Unit
1602 -- All done if we successfully loaded the subunit
1606 then
1609 -- If the file was empty or seriously mangled, the unit itself may
1610 -- be missing.
1613 Error_Msg_N
1617 Error_Msg_N
1620 else
1628 then
1631 else
1632 Set_Corresponding_Body (
1638 -- Start of processing for Analyze_Proper_Body
1640 begin
1641 -- If the subunit is already loaded, it means that the main unit is a
1642 -- subunit, and that the current unit is one of its parents which was
1643 -- being analyzed to provide the needed context for the analysis of the
1644 -- subunit. In this case we analyze the subunit and continue with the
1645 -- parent, without looking a subsequent subunits.
1649 -- If the proper body is already linked to the stub node, the stub is
1650 -- in a generic unit and just needs analyzing.
1656 -- Otherwise we must load the subunit and link to it
1658 else
1659 -- Load the subunit, this must work, since we originally loaded
1660 -- the subunit earlier on. So this will not really load it, just
1661 -- give access to it.
1663 Unum :=
1664 Load_Unit
1670 -- And analyze the subunit in the parent context (note that we
1671 -- do not call Semantics, since that would remove the parent
1672 -- context). Because of this, we have to manually reset the
1673 -- compiler state to Analyzing since it got destroyed by Load.
1678 -- Check that the proper body is a subunit and not a child
1679 -- unit. If the unit was previously loaded, the error will
1680 -- have been emitted when copying the generic node, so we
1681 -- just return to avoid cascaded errors.
1693 -- If the main unit is a subunit, then we are just performing semantic
1694 -- analysis on that subunit, and any other subunits of any parent unit
1695 -- should be ignored, except that if we are building trees for ASIS
1696 -- usage we want to annotate the stub properly.
1700 then
1702 Optional_Subunit;
1705 -- But before we return, set the flag for unloaded subunits. This
1706 -- will suppress junk warnings of variables in the same declarative
1707 -- part (or a higher level one) that are in danger of looking unused
1708 -- when in fact there might be a declaration in the subunit that we
1709 -- do not intend to load.
1714 -- If the subunit is not already loaded, and we are generating code,
1715 -- then this is the case where compilation started from the parent, and
1716 -- we are generating code for an entire subunit tree. In that case we
1717 -- definitely need to load the subunit.
1719 -- In order to continue the analysis with the rest of the parent,
1720 -- and other subunits, we load the unit without requiring its
1721 -- presence, and emit a warning if not found, rather than terminating
1722 -- the compilation abruptly, as for other missing file problems.
1726 -- If the proper body is already linked to the stub node, the stub is
1727 -- in a generic unit and just needs analyzing.
1729 -- We update the version. Although we are not strictly technically
1730 -- semantically dependent on the subunit, given our approach of macro
1731 -- substitution of subunits, it makes sense to include it in the
1732 -- version identification.
1739 -- Otherwise we must load the subunit and link to it
1741 else
1742 Unum :=
1743 Load_Unit
1749 -- Give message if we did not get the unit Emit warning even if
1750 -- missing subunit is not within main unit, to simplify debugging.
1754 then
1756 Error_Msg_File_1 :=
1758 Error_Msg_N
1763 -- Load_Unit may reset Compiler_State, since it may have been
1764 -- necessary to parse an additional units, so we make sure that
1765 -- we reset it to the Analyzing state.
1772 Write_Eol;
1775 declare
1778 begin
1779 -- Check for child unit instead of subunit
1782 Error_Msg_N
1786 -- OK, we have a subunit
1788 else
1789 -- Set corresponding stub (even if errors)
1793 -- Collect SCO information for loaded subunit if we are
1794 -- in the main unit).
1796 if Generate_SCO
1797 and then
1798 In_Extended_Main_Source_Unit
1800 then
1804 -- Analyze the unit if semantics active
1810 -- Set the library unit pointer in any case
1814 -- We update the version. Although we are not technically
1815 -- semantically dependent on the subunit, given our
1816 -- approach of macro substitution of subunits, it makes
1817 -- sense to include it in the version identification.
1825 -- The remaining case is when the subunit is not already loaded and
1826 -- we are not generating code. In this case we are just performing
1827 -- semantic analysis on the parent, and we are not interested in
1828 -- the subunit. For subprograms, analyze the stub as a body. For
1829 -- other entities the stub has already been marked as completed.
1831 else
1832 Optional_Subunit;
1836 ----------------------------------
1837 -- Analyze_Protected_Body_Stub --
1838 ----------------------------------
1843 begin
1846 -- First occurrence of name may have been as an incomplete type
1854 then
1856 else
1864 ----------------------------------
1865 -- Analyze_Subprogram_Body_Stub --
1866 ----------------------------------
1868 -- A subprogram body stub can appear with or without a previous spec. If
1869 -- there is one, then the analysis of the body will find it and verify
1870 -- conformance. The formals appearing in the specification of the stub play
1871 -- no role, except for requiring an additional conformance check. If there
1872 -- is no previous subprogram declaration, the stub acts as a spec, and
1873 -- provides the defining entity for the subprogram.
1878 begin
1881 -- Verify that the identifier for the stub is unique within this
1882 -- declarative part.
1885 N_Package_Body,
1886 N_Subprogram_Body)
1887 then
1891 loop
1895 then
1903 -- Treat stub as a body, which checks conformance if there is a previous
1904 -- declaration, or else introduces entity and its signature.
1910 ---------------------
1911 -- Analyze_Subunit --
1912 ---------------------
1914 -- A subunit is compiled either by itself (for semantic checking) or as
1915 -- part of compiling the parent (for code generation). In either case, by
1916 -- the time we actually process the subunit, the parent has already been
1917 -- installed and analyzed. The node N is a compilation unit, whose context
1918 -- needs to be treated here, because we come directly here from the parent
1919 -- without calling Analyze_Compilation_Unit.
1921 -- The compilation context includes the explicit context of the subunit,
1922 -- and the context of the parent, together with the parent itself. In order
1923 -- to compile the current context, we remove the one inherited from the
1924 -- parent, in order to have a clean visibility table. We restore the parent
1925 -- context before analyzing the proper body itself. On exit, we remove only
1926 -- the explicit context of the subunit.
1939 -- Capture names in use clauses of the subunit. This must be done before
1940 -- re-installing parent declarations, because items in the context must
1941 -- not be hidden by declarations local to the parent.
1944 -- Recursive procedure to restore scope of all ancestors of subunit,
1945 -- from outermost in. If parent is not a subunit, the call to install
1946 -- context installs context of spec and (if parent is a child unit) the
1947 -- context of its parents as well. It is confusing that parents should
1948 -- be treated differently in both cases, but the semantics are just not
1949 -- identical.
1952 -- As part of the removal of the parent scope, the use clauses are
1953 -- removed, to be reinstalled when the context of the subunit has been
1954 -- analyzed. Use clauses may also have been affected by the analysis of
1955 -- the context of the subunit, so they have to be applied again, to
1956 -- insure that the compilation environment of the rest of the parent
1957 -- unit is identical.
1960 -- Remove current scope from scope stack, and preserve the list of use
1961 -- clauses in it, to be reinstalled after context is analyzed.
1963 -----------------------------
1964 -- Analyze_Subunit_Context --
1965 -----------------------------
1972 begin
1975 -- Make withed units immediately visible. If child unit, make the
1976 -- ultimate parent immediately visible.
1982 -- Protect frontend against previous errors in context clauses
1988 else
2020 -- Reset visibility of withed units. They will be made visible again
2021 -- when we install the subunit context.
2027 -- Protect frontend against previous errors in context clauses
2031 then
2048 ------------------------
2049 -- Re_Install_Parents --
2050 ------------------------
2055 begin
2062 -- If the subunit occurs within a child unit, we must restore the
2063 -- immediate visibility of any siblings that may occur in context.
2075 -- Make entities in scope visible again. For child units, restore
2076 -- visibility only if they are actually in context.
2082 then
2089 -- A subunit appears within a body, and for a nested subunits all the
2090 -- parents are bodies. Restore full visibility of their private
2091 -- entities.
2099 ----------------------------
2100 -- Re_Install_Use_Clauses --
2101 ----------------------------
2105 begin
2113 ------------------
2114 -- Remove_Scope --
2115 ------------------
2120 begin
2135 Pop_Scope;
2138 -- Start of processing for Analyze_Subunit
2140 begin
2142 declare
2145 begin
2156 -- Save current use clauses
2158 Remove_Scope;
2161 -- Now remove parents and their context, including enclosing subunits
2162 -- and the outer parent body which is not a subunit.
2169 Remove_Scope;
2174 Remove_Scope;
2184 Analyze_Subunit_Context;
2189 -- If the context includes a child unit of the parent of the subunit,
2190 -- the parent will have been removed from visibility, after compiling
2191 -- that cousin in the context. The visibility of the parent must be
2192 -- restored now. This also applies if the context includes another
2193 -- subunit of the same parent which in turn includes a child unit in
2194 -- its context.
2199 and then not Is_Immediately_Visible
2201 then
2208 Re_Install_Use_Clauses;
2211 -- Restore state of suppress flags for current body
2215 -- If the subunit is within a child unit, then siblings of any parent
2216 -- unit that appear in the context clause of the subunit must also be
2217 -- made immediately visible.
2227 -- The subunit may contain a with_clause on a sibling of some ancestor.
2228 -- Removing the context will remove from visibility those ancestor child
2229 -- units, which must be restored to the visibility they have in the
2230 -- enclosing body.
2233 declare
2235 begin
2239 loop
2248 ----------------------------
2249 -- Analyze_Task_Body_Stub --
2250 ----------------------------
2256 begin
2259 -- First occurrence of name may have been as an incomplete type
2267 else
2273 -- Set elaboration flag to indicate that entity is callable. This
2274 -- cannot be done in the expansion of the body itself, because the
2275 -- proper body is not in a declarative part. This is only done if
2276 -- expansion is active, because the context may be generic and the
2277 -- flag not defined yet.
2282 Name =>
2290 -------------------------
2291 -- Analyze_With_Clause --
2292 -------------------------
2294 -- Analyze the declaration of a unit in a with clause. At end, label the
2295 -- with clause with the defining entity for the unit.
2299 -- Retrieve the original kind of the unit node, before analysis. If it
2300 -- is a subprogram instantiation, its analysis below will rewrite the
2301 -- node as the declaration of the wrapper package. If the same
2302 -- instantiation appears indirectly elsewhere in the context, it will
2303 -- have been analyzed already.
2314 -- Set True if the unit currently being compiled is an internal unit
2319 begin
2322 -- If this is an internal unit which is a renaming, then this is a
2323 -- violation of No_Obsolescent_Features.
2325 -- Note: this is not quite right if the user defines one of these units
2326 -- himself, but that's a marginal case, and fixing it is hard ???
2329 declare
2332 begin
2334 and then not
2336 then
2342 -- Save current restriction set, does not apply to with'ed unit
2346 -- Several actions are skipped for dummy packages (those supplied for
2347 -- with's where no matching file could be found). Such packages are
2348 -- identified by the Sloc value being set to No_Location.
2352 -- Ada 2005 (AI-50217): Build visibility structures but do not
2353 -- analyze the unit.
2362 -- We reset ordinary style checking during the analysis of a with'ed
2363 -- unit, but we do NOT reset GNAT special analysis mode (the latter
2364 -- definitely *does* apply to with'ed units).
2370 -- If the library unit is a predefined unit, and we are in high
2371 -- integrity mode, then temporarily reset Configurable_Run_Time_Mode
2372 -- for the analysis of the with'ed unit. This mode does not prevent
2373 -- explicit with'ing of run-time units.
2375 if Configurable_Run_Time_Mode
2377 then
2382 else
2390 -- Check restrictions, except that we skip the check if this is an
2391 -- internal unit unless we are compiling the internal unit as the
2392 -- main unit. We also skip this for dummy packages.
2400 -- Deal with special case of GNAT.Current_Exceptions which interacts
2401 -- with the optimization of local raise statements into gotos.
2407 or else
2409 then
2414 -- Check for inappropriate with of internal implementation unit if we
2415 -- are not compiling an internal unit. We do not issue this message
2416 -- for implicit with's generated by the compiler itself.
2418 if Implementation_Unit_Warnings
2419 and then not Intunit
2421 then
2422 declare
2426 begin
2430 -- Add alternative name if available, otherwise issue a
2431 -- general warning message.
2435 else
2436 Error_Msg_F
2443 and then Warn_On_Ada_2005_Compatibility
2444 then
2451 -- Semantic analysis of a generic unit is performed on a copy of
2452 -- the original tree. Retrieve the entity on which semantic info
2453 -- actually appears.
2458 -- Note: in the following test, Unit_Kind is the original Nkind, but in
2459 -- the case of an instantiation, semantic analysis above will have
2460 -- replaced the unit by its instantiated version. If the instance body
2461 -- has been generated, the instance now denotes the body entity. For
2462 -- visibility purposes we need the entity of its spec.
2466 N_Package_Instantiation)
2468 then
2473 then
2474 -- If the instance has not been rewritten as a package declaration,
2475 -- then it appeared already in a previous with clause. Retrieve
2476 -- the entity from the previous instance.
2482 -- The visible subprogram is created during instantiation, and is
2483 -- an attribute of the wrapper package. We retrieve the wrapper
2484 -- package directly from the instantiation node. If the instance
2485 -- is inlined the unit is still an instantiation. Otherwise it has
2486 -- been rewritten as the declaration of the wrapper itself.
2489 E_Name :=
2490 Related_Instance
2492 else
2498 then
2504 then
2505 -- For a child unit that has no spec, one has been created and
2506 -- analyzed. The entity required is that of the spec.
2510 else
2516 -- Child unit in a with clause
2521 -- Restore style checks and restrictions
2526 -- Record the reference, but do NOT set the unit as referenced, we want
2527 -- to consider the unit as unreferenced if this is the only reference
2528 -- that occurs.
2533 -- Generate references and check No_Dependence restriction for parents
2546 -- If E_Name is the dummy entity for a nonexistent unit, its scope
2547 -- is set to Standard_Standard, and no attempt should be made to
2548 -- further unwind scopes.
2557 then
2558 -- If the entity is set without its unit being compiled, the
2559 -- original parent is a renaming, and Par_Name is the renamed
2560 -- entity. For visibility purposes, we need the original entity,
2561 -- which must be analyzed now because Load_Unit directly retrieves
2562 -- the renamed unit, and the renaming declaration itself has not
2563 -- been analyzed.
2574 -- If the withed unit is System, and a system extension pragma is
2575 -- present, compile the extension now, rather than waiting for a
2576 -- visibility check on a specific entity.
2582 then
2583 -- If the extension is not present, an error will have been emitted
2588 -- Ada 2005 (AI-262): Remove from visibility the entity corresponding
2589 -- to private_with units; they will be made visible later (just before
2590 -- the private part is analyzed)
2597 ------------------------------
2598 -- Check_Private_Child_Unit --
2599 ------------------------------
2611 -- Returns true if and only if the library unit is declared with
2612 -- an explicit designation of private.
2614 -----------------------------
2615 -- Is_Private_Library_Unit --
2616 -----------------------------
2621 begin
2625 -- Start of processing for Check_Private_Child_Unit
2627 begin
2634 -- The parent is itself a body. The parent entity is to be found in
2635 -- the corresponding spec.
2640 -- If the parent itself is a subunit, Curr_Unit is the entity of the
2641 -- enclosing body, retrieve the spec entity which is the proper
2642 -- ancestor we need for the following tests.
2650 else
2658 else
2663 -- Loop through context items
2668 -- Ada 2005 (AI-262): Allow private_with of a private child package
2669 -- in public siblings
2675 then
2678 declare
2684 begin
2685 -- If the child unit is a public child then locate the nearest
2686 -- private ancestor. Child_Parent will then be set to the
2687 -- parent of that ancestor.
2692 loop
2704 loop
2705 Curr_Private :=
2718 then
2719 Error_Msg_NE
2723 else
2724 Error_Msg_N
2726 Error_Msg_NE
2731 elsif Curr_Private
2736 then
2739 else
2740 Error_Msg_NE
2752 ----------------------
2753 -- Check_Stub_Level --
2754 ----------------------
2760 begin
2762 N_Subprogram_Body,
2763 N_Task_Body,
2764 N_Protected_Body)
2766 then
2769 -- In an instance, a missing stub appears at any level. A warning
2770 -- message will have been emitted already for the missing file.
2780 ------------------------
2781 -- Expand_With_Clause --
2782 ------------------------
2791 -- Build name to be used in implicit with_clause. In most cases this
2792 -- is the source name, but if renamings are present we must make the
2793 -- original unit visible, not the one it renames. The entity in the
2794 -- with clause is the renamed unit, but the identifier is the one from
2795 -- the source, which allows us to recover the unit renaming.
2797 ---------------------
2798 -- Build_Unit_Name --
2799 ---------------------
2806 begin
2809 -- If the parent unit P in the name of the with_clause for P.Q is
2810 -- a renaming of package R, then the entity of the parent is set
2811 -- to R, but the identifier retains Chars (P) to be consistent
2812 -- with the source (see details in lib-load). However the implicit
2813 -- with_clause for the parent must make the entity for P visible,
2814 -- because P.Q may be used as a prefix within the current unit.
2815 -- The entity for P is the current_entity with that name, because
2816 -- the package renaming declaration for it has just been analyzed.
2817 -- Note that this case can only happen if P.Q has already appeared
2818 -- in a previous with_clause in a related unit, such as the
2819 -- library body of the current unit.
2826 else
2830 else
2835 and then
2837 = N_Package_Renaming_Declaration
2838 then
2839 -- The name in the with_clause is of the form A.B.C, and B is
2840 -- given by a renaming declaration. In that case we may not
2841 -- have analyzed the unit for B, but replaced it directly in
2842 -- lib-load with the unit it renames. We have to make A.B
2843 -- visible, so analyze the declaration for B now, in case it
2844 -- has not been done yet.
2847 Analyze
2848 (Parent
2852 Result :=
2862 -- Start of processing for Expand_With_Clause
2864 begin
2866 Withn :=
2876 -- If the unit is a package declaration, a private_with_clause on a
2877 -- child unit implies the implicit with on the parent is also private.
2894 -----------------------
2895 -- Get_Parent_Entity --
2896 -----------------------
2899 begin
2902 then
2903 return Defining_Entity
2907 else
2912 ---------------------
2913 -- Has_With_Clause --
2914 ---------------------
2916 function Has_With_Clause
2920 is
2924 -- Return the entity for the unit named in a [limited] with clause
2926 ----------------
2927 -- Named_Unit --
2928 ----------------
2931 begin
2934 else
2939 -- Start of processing for Has_With_Clause
2941 begin
2948 then
2959 -----------------------------
2960 -- Implicit_With_On_Parent --
2961 -----------------------------
2963 procedure Implicit_With_On_Parent
2966 is
2974 -- Build prefix of child unit name. Recurse if needed
2977 -- If the unit is a child unit, build qualified name with all ancestors
2979 -------------------------
2980 -- Build_Ancestor_Name --
2981 -------------------------
2988 begin
2989 -- Ancestor may have been rewritten as a package body. Retrieve
2990 -- the original spec to trace earlier ancestors.
2994 then
3000 else
3001 return
3008 ---------------------
3009 -- Build_Unit_Name --
3010 ---------------------
3015 begin
3019 else
3020 Result :=
3030 -- Start of processing for Implicit_With_On_Parent
3032 begin
3033 -- The unit of the current compilation may be a package body that
3034 -- replaces an instance node. In this case we need the original instance
3035 -- node to construct the proper parent name.
3039 then
3043 -- We add the implicit with if the child unit is the current unit being
3044 -- compiled. If the current unit is a body, we do not want to add an
3045 -- implicit_with a second time to the corresponding spec.
3049 then
3061 -- Node is placed at the beginning of the context items, so that
3062 -- subsequent use clauses on the parent can be validated.
3075 --------------
3076 -- In_Chain --
3077 --------------
3082 begin
3087 else
3095 ---------------------
3096 -- Install_Context --
3097 ---------------------
3102 begin
3112 -----------------------------
3113 -- Install_Context_Clauses --
3114 -----------------------------
3124 begin
3125 -- First skip configuration pragmas at the start of the context. They
3126 -- are not technically part of the context clause, but that's where the
3127 -- parser puts them. Note they were analyzed in Analyze_Context.
3133 loop
3137 -- Loop through the actual context clause items. We process everything
3138 -- except Limited_With clauses in this routine. Limited_With clauses
3139 -- are separately installed (see Install_Limited_Context_Clauses).
3143 -- Case of explicit WITH clause
3147 then
3150 -- Limited withed units will be installed later
3154 -- If Name (Item) is not an entity name, something is wrong, and
3155 -- this will be detected in due course, for now ignore the item
3175 -- If the unit is a subprogram instance, it appears nested within
3176 -- a package that carries the parent information.
3180 then
3187 else
3188 -- If not an expanded name, the child unit must be a
3189 -- renaming, nothing to do.
3197 then
3198 Implicit_With_On_Parent
3202 -- Check license conditions unless this is a dummy unit
3214 -- Signal error of bad license
3216 -------------------
3217 -- License_Error --
3218 -------------------
3221 begin
3222 Error_Msg_N
3227 -- Start of processing for License_Check
3229 begin
3230 -- Exclude license check if withed unit is an internal unit.
3231 -- This situation arises e.g. with the GPL version of GNAT.
3236 -- Otherwise check various cases
3237 else
3244 License_Error;
3249 License_Error;
3254 License_Error;
3264 -- Case of USE PACKAGE clause
3269 -- Case of USE TYPE clause
3274 -- case of PRAGMA
3286 -- The unit also has implicit with_clauses on its own parents
3295 -- If the unit is a body, the context of the specification must also
3296 -- be installed. That includes private with_clauses in that context.
3301 then
3304 -- Only install private with-clauses of a spec that comes from
3305 -- source, excluding specs created for a subprogram body that is
3306 -- a child unit.
3309 Install_Private_With_Clauses
3315 -- If the unit is the body of a public child unit, the private
3316 -- declarations of the parent must be made visible. If the child
3317 -- unit is private, the private declarations have been installed
3318 -- already in the call to Install_Parents for the spec. Installing
3319 -- private declarations must be done for all ancestors of public
3320 -- child units. In addition, sibling units mentioned in the
3321 -- context clause of the body are directly visible.
3323 declare
3328 begin
3336 then
3347 -- For a package body, children in context are immediately visible
3353 N_Generic_Subprogram_Declaration,
3354 N_Package_Declaration,
3355 N_Subprogram_Declaration)
3356 then
3359 Set_Is_Private_Descendant
3364 else
3365 Set_Is_Private_Descendant
3376 -------------------------------------
3377 -- Install_Limited_Context_Clauses --
3378 -------------------------------------
3384 -- Check that the unlimited view of a given compilation_unit is not
3385 -- already visible through "use + renamings".
3388 -- Check that if a limited_with clause of a given compilation_unit
3389 -- mentions a descendant of a private child of some library unit, then
3390 -- the given compilation_unit shall be the declaration of a private
3391 -- descendant of that library unit, or a public descendant of such. The
3392 -- code is analogous to that of Check_Private_Child_Unit but we cannot
3393 -- use entities on the limited with_clauses because their units have not
3394 -- been analyzed, so we have to climb the tree of ancestors looking for
3395 -- private keywords.
3397 procedure Expand_Limited_With_Clause
3401 -- If a child unit appears in a limited_with clause, there are implicit
3402 -- limited_with clauses on all parents that are not already visible
3403 -- through a regular with clause. This procedure creates the implicit
3404 -- limited with_clauses for the parents and loads the corresponding
3405 -- units. The shadow entities are created when the inserted clause is
3406 -- analyzed. Implements Ada 2005 (AI-50217).
3409 -- When compiling a unit Q descended from some parent unit P, a limited
3410 -- with_clause in the context of P that names some other ancestor of Q
3411 -- must not be installed because the ancestor is immediately visible.
3413 ---------------------
3414 -- Check_Renamings --
3415 ---------------------
3425 begin
3428 -- Protect the frontend against previous critical errors
3431 when N_Subprogram_Declaration |
3432 N_Package_Declaration |
3433 N_Generic_Subprogram_Declaration |
3434 N_Generic_Package_Declaration =>
3441 -- Check "use + renamings"
3449 -- Look only at use package clauses
3453 -- Traverse the list of packages
3463 then
3464 -- The unlimited view is visible through use clause and
3465 -- renamings. There is no need to generate the error
3466 -- message here because Is_Visible_Through_Renamings
3467 -- takes care of generating the precise error message.
3473 -- The use clause may refer to a local package.
3474 -- Check all the enclosing scopes.
3479 loop
3484 Error_Msg_N
3497 -- Recursive call to check all the ancestors
3504 ---------------------------------------
3505 -- Check_Private_Limited_Withed_Unit --
3506 ---------------------------------------
3513 begin
3514 -- Compilation unit of the parent of the withed library unit
3518 -- If the child unit is a public child, then locate its nearest
3519 -- private ancestor, if any, then Child_Parent will then be set to
3520 -- the parent of that ancestor.
3525 loop
3536 -- Traverse all the ancestors of the current compilation unit to
3537 -- check if it is a descendant of named library unit.
3544 loop
3550 Error_Msg_N
3552 Error_Msg_NE
3557 or else Curr_Private
3560 N_Subprogram_Body,
3561 N_Subunit)
3562 then
3563 -- Current unit is private, of descendant of a private unit
3567 else
3568 Error_Msg_NE
3574 --------------------------------
3575 -- Expand_Limited_With_Clause --
3576 --------------------------------
3578 procedure Expand_Limited_With_Clause
3582 is
3588 -- Returns true if the context already includes a with_clause for
3589 -- this unit. If the with_clause is non-limited, the unit is fully
3590 -- visible and an implicit limited_with should not be created. If
3591 -- there is already a limited_with clause for W, a second one is
3592 -- simply redundant.
3594 --------------------------
3595 -- Previous_Withed_Unit --
3596 --------------------------
3601 begin
3602 -- A limited with_clause cannot appear in the same context_clause
3603 -- as a nonlimited with_clause which mentions the same library.
3609 then
3619 -- Start of processing for Expand_Limited_With_Clause
3621 begin
3626 -- Create node for name of withed unit
3628 Withn :=
3633 Withn :=
3645 Unum :=
3646 Load_Unit
3652 -- Do not generate a limited_with_clause on the current unit. This
3653 -- path is taken when a unit has a limited_with clause on one of its
3654 -- child units.
3661 Set_Corresponding_Spec
3668 -- Add implicit limited_with_clauses for parents of child units
3669 -- mentioned in limited_with clauses.
3685 ----------------------
3686 -- Is_Ancestor_Unit --
3687 ----------------------
3692 begin
3696 else
3701 -- Start of processing for Install_Limited_Context_Clauses
3703 begin
3708 then
3710 Expand_Limited_With_Clause
3718 then
3722 -- A unit may have a limited with on itself if it has a limited
3723 -- with_clause on one of its child units. In that case it is
3724 -- already being compiled and it makes no sense to install its
3725 -- limited view.
3727 -- If the item is a limited_private_with_clause, install it if the
3728 -- current unit is a body or if it is a private child. Otherwise
3729 -- the private clause is installed before analyzing the private
3730 -- part of the current unit.
3734 and then
3735 not Is_Ancestor_Unit
3737 then
3741 N_Subprogram_Body,
3742 N_Subunit)
3743 then
3752 -- Ada 2005 (AI-412): Examine visible declarations of a package spec,
3753 -- looking for incomplete subtype declarations of incomplete types
3754 -- visible through a limited with clause.
3759 then
3760 declare
3765 begin
3769 and then
3771 and then
3773 then
3779 -- Convert an incomplete subtype declaration into a
3780 -- corresponding non-limited view subtype declaration.
3781 -- This is usually the case when analyzing a body that
3782 -- has regular with clauses, when the spec has limited
3783 -- ones.
3785 -- If the non-limited view is still incomplete, it is
3786 -- the dummy entry already created, and the declaration
3787 -- cannot be reanalyzed. This is the case when installing
3788 -- a parent unit that has limited with-clauses.
3796 -- Reanalyze the declaration, suppressing the call to
3797 -- Enter_Name to avoid duplicate names.
3799 Analyze_Subtype_Declaration
3811 ---------------------
3812 -- Install_Parents --
3813 ---------------------
3821 begin
3831 N_Generic_Package_Declaration)
3833 then
3834 Error_Msg_N
3838 Error_Msg_N
3846 -- Verify that a child of an instance is itself an instance, or the
3847 -- renaming of one. Given that an instance that is a unit is replaced
3848 -- with a package declaration, check against the original node. The
3849 -- parent may be currently being instantiated, in which case it appears
3850 -- as a declaration, but the generic_parent is already established
3851 -- indicating that we deal with an instance.
3856 or else
3859 then
3861 else
3862 Error_Msg_N
3864 Lib_Unit);
3868 -- This is the recursive call that ensures all parents are loaded
3875 -- Now we can install the context for this parent
3881 -- The child unit is in the declarative region of the parent. The parent
3882 -- must therefore appear in the scope stack and be visible, as when
3883 -- compiling the corresponding body. If the child unit is private or it
3884 -- is a package body, private declarations must be accessible as well.
3885 -- Use declarations in the parent must also be installed. Finally, other
3886 -- child units of the same parent that are in the context are
3887 -- immediately visible.
3889 -- Find entity for compilation unit, and set its private descendant
3890 -- status as needed. Indicate that it is a compilation unit, which is
3891 -- redundant in general, but needed if this is a generated child spec
3892 -- for a child body without previous spec.
3906 -- Save current visibility of unit
3914 -- If the parent is a generic unit, its formal part may contain formal
3915 -- packages and use clauses for them.
3921 if Is_Private
3923 then
3930 ----------------------------------
3931 -- Install_Private_With_Clauses --
3932 ----------------------------------
3938 begin
3942 Write_Eol;
3950 then
3955 else
3965 ----------------------
3966 -- Install_Siblings --
3967 ----------------------
3974 begin
3975 -- Iterate over explicit with clauses, and check whether the scope of
3976 -- each entity is an ancestor of the current unit, in which case it is
3977 -- immediately visible.
3982 -- Do not install private_with_clauses declaration, unless unit
3983 -- is itself a private child unit, or is a body. Note that for a
3984 -- subprogram body the private_with_clause does not take effect until
3985 -- after the specification.
3990 then
3996 then
4001 then
4004 -- Check for the presence of another unit in the context that
4005 -- may be inadvertently hidden by the child.
4012 then
4013 declare
4016 begin
4021 then
4022 Error_Msg_NE
4034 -- The With_Clause may be on a grand-child or one of its further
4035 -- descendants, which makes a child immediately visible. Examine
4036 -- ancestry to determine whether such a child exists. For example,
4037 -- if current unit is A.C, and with_clause is on A.X.Y.Z, then X
4038 -- is immediately visible.
4041 declare
4044 begin
4057 -- If the item is a private with-clause on a child unit, the parent
4058 -- may have been installed already, but the child unit must remain
4059 -- invisible until installed in a private part or body, unless there
4060 -- is already a regular with_clause for it in the current unit.
4066 declare
4070 -- Scan context of current unit, to check whether there is
4071 -- a with_clause on the same unit as a private with-clause
4072 -- on a parent, in which case child unit is visible. If the
4073 -- unit is a grand-child, the same applies to its parent.
4075 ----------------
4076 -- In_Context --
4077 ----------------
4080 begin
4081 Clause :=
4088 then
4090 or else
4093 then
4104 begin
4114 ---------------------------------
4115 -- Install_Limited_Withed_Unit --
4116 ---------------------------------
4127 -- A unit mentioned in a limited with_clause may not be mentioned in
4128 -- a regular with_clause, but must still be included in the current
4129 -- partition. We need to determine whether the unit needs a body, so
4130 -- that the binder can determine the name of the file to be compiled.
4131 -- Checking whether a unit needs a body can be done without semantic
4132 -- analysis, by examining the nature of the declarations in the package.
4134 function Has_Limited_With_Clause
4137 -- Determine whether any package in the ancestor chain starting with
4138 -- C_Unit has a limited with clause for package Pack.
4141 -- Check if some package installed though normal with-clauses has a
4142 -- renaming declaration of package P. AARM 10.1.2(21/2).
4144 -------------------------
4145 -- Check_Body_Required --
4146 -------------------------
4153 -- Recursive procedure that does the work and checks nested packages
4155 ------------------------
4156 -- Check_Declarations --
4157 ------------------------
4166 -- If a pragma import applies to a previous subprogram, the
4167 -- enclosing unit may not need a body. The processing is syntactic
4168 -- and does not require a declaration to be analyzed. The code
4169 -- below also handles pragma Import when applied to a subprogram
4170 -- that renames another. In this case the pragma applies to the
4171 -- renamed entity.
4172 --
4173 -- Chains of multiple renames are not handled by the code below.
4174 -- It is probably impossible to handle all cases without proper
4175 -- name resolution. In such cases the algorithm is conservative
4176 -- and will indicate that a body is needed???
4178 -------------------------
4179 -- Check_Pragma_Import --
4180 -------------------------
4189 -- Make one pass over list of subprograms. Called again if
4190 -- subprogram is a renaming. E is known to be an identifier.
4192 ---------------------
4193 -- Remove_Homonyms --
4194 ---------------------
4198 -- Name of renamed entity, if any
4200 begin
4205 /= N_Subprogram_Renaming_Declaration
4206 then
4210 else
4214 else
4226 -- Renaming of attribute
4228 else
4234 -- Start of processing for Check_Pragma_Import
4236 begin
4237 -- Find name of entity in Import pragma. We have not analyzed
4238 -- the construct, so we must guard against syntax errors.
4244 then
4246 else
4253 -- Start of processing for Check_Declarations
4255 begin
4256 -- Search for Elaborate Body pragma
4261 loop
4270 -- Look for declarations that require the presence of a body. We
4271 -- have already skipped pragmas at the start of the list.
4275 -- Subprogram that comes from source means body may be needed.
4276 -- Save for subsequent examination of import pragmas.
4280 N_Subprogram_Renaming_Declaration,
4281 N_Generic_Subprogram_Declaration))
4282 then
4285 -- Package declaration of generic package declaration. We need
4286 -- to recursively examine nested declarations.
4289 N_Generic_Package_Declaration)
4290 then
4295 then
4302 -- Same set of tests for private part. In addition to subprograms
4303 -- detect the presence of Taft Amendment types (incomplete types
4304 -- completed in the body).
4310 N_Subprogram_Renaming_Declaration,
4311 N_Generic_Subprogram_Declaration))
4312 then
4316 N_Generic_Package_Declaration)
4317 then
4320 -- Collect incomplete type declarations for separate pass
4327 then
4334 -- Now check incomplete declarations to locate Taft amendment
4335 -- types. This can be done by examining the defining identifiers
4336 -- of type declarations without real semantic analysis.
4338 declare
4341 begin
4349 then
4356 -- If no completion, this is a TAT, and a body is needed
4367 -- Finally, check whether there are subprograms that still require
4368 -- a body, i.e. are not renamings or null.
4371 declare
4375 begin
4381 = N_Subprogram_Renaming_Declaration
4382 then
4387 then
4390 else
4401 -- Start of processing for Check_Body_Required
4403 begin
4404 -- If this is an imported package (Java and CIL usage) no body is
4405 -- needed. Scan list of pragmas that may follow a compilation unit
4406 -- to look for a relevant pragma Import.
4409 declare
4412 begin
4417 then
4429 -----------------------------
4430 -- Has_Limited_With_Clause --
4431 -----------------------------
4433 function Has_Limited_With_Clause
4436 is
4440 begin
4447 -- Retrieve the Compilation_Unit node for Par and determine if
4448 -- its context clauses contain a limited with for Pack.
4460 -- If there are more ancestors, climb up the tree, otherwise we
4461 -- are done.
4465 else
4473 ----------------------------------
4474 -- Is_Visible_Through_Renamings --
4475 ----------------------------------
4484 begin
4485 -- Example of the error detected by this subprogram:
4487 -- package P is
4488 -- type T is ...
4489 -- end P;
4491 -- with P;
4492 -- package Q is
4493 -- package Ren_P renames P;
4494 -- end Q;
4496 -- with Q;
4497 -- package R is ...
4499 -- limited with P; -- ERROR
4500 -- package R.C is ...
4504 loop
4510 N_Package_Declaration
4511 then
4512 Decl :=
4513 First (Visible_Declarations
4518 then
4519 -- Generate the error message only if the current unit
4520 -- is a package declaration; in case of subprogram
4521 -- bodies and package bodies we just return True to
4522 -- indicate that the limited view must not be
4523 -- installed.
4526 Error_Msg_N
4530 Error_Msg_NE
4547 -- If it is a body not acting as spec, follow pointer to the
4548 -- corresponding spec, otherwise follow pointer to parent spec.
4553 then
4556 -- Aux_Unit is a body that acts as a spec. Clause has
4557 -- already been flagged as illegal.
4561 else
4565 else
4575 -- Start of processing for Install_Limited_Withed_Unit
4577 begin
4580 -- In case of limited with_clause on subprograms, generics, instances,
4581 -- or renamings, the corresponding error was previously posted and we
4582 -- have nothing to do here. If the file is missing altogether, it has
4583 -- no source location.
4587 then
4593 -- Handle child packages
4600 -- Do not install the limited-view if the context of the unit is already
4601 -- available through a regular with clause.
4605 then
4609 -- Do not install the limited-view if the full-view is already visible
4610 -- through renaming declarations.
4616 -- Do not install the limited view if this is the unit being analyzed.
4617 -- This unusual case will happen when a unit has a limited_with clause
4618 -- on one of its children. The compilation of the child forces the load
4619 -- of the parent which tries to install the limited view of the child
4620 -- again. Installing the limited view must also be disabled when
4621 -- compiling the body of the child unit.
4624 or else
4627 then
4631 -- This scenario is similar to the one above, the difference is that the
4632 -- compilation of sibling Par.Sib forces the load of parent Par which
4633 -- tries to install the limited view of Lim_Pack [1]. However Par.Sib
4634 -- has a with clause for Lim_Pack [2] in its body, and thus needs the
4635 -- non-limited views of all entities from Lim_Pack.
4637 -- limited with Lim_Pack; -- [1]
4638 -- package Par is ... package Lim_Pack is ...
4640 -- with Lim_Pack; -- [2]
4641 -- package Par.Sib is ... package body Par.Sib is ...
4643 -- In this case Main_Unit_Entity is the spec of Par.Sib and Current_
4644 -- Sem_Unit is the body of Par.Sib.
4650 -- The body has a regular with clause
4655 -- One of the ancestors has a limited with clause
4658 N_Package_Specification
4660 then
4664 -- A common use of the limited-with is to have a limited-with in the
4665 -- package spec, and a normal with in its package body. For example:
4667 -- limited with X; -- [1]
4668 -- package A is ...
4670 -- with X; -- [2]
4671 -- package body A is ...
4673 -- The compilation of A's body installs the context clauses found at [2]
4674 -- and then the context clauses of its specification (found at [1]). As
4675 -- a consequence, at [1] the specification of X has been analyzed and it
4676 -- is immediately visible. According to the semantics of limited-with
4677 -- context clauses we don't install the limited view because the full
4678 -- view of X supersedes its limited view.
4681 and then
4684 then
4691 Write_Eol;
4694 -- If the unit has not been analyzed and the limited view has not been
4695 -- already installed then we install it.
4700 -- Minimum decoration
4712 -- Place entity on visibility structure
4720 Write_Eol;
4723 -- Install the incomplete view. The first element of the limited
4724 -- view is a header (an E_Package entity) used to reference the
4725 -- first shadow entity in the private part of the package.
4732 loop
4739 Write_Eol;
4746 -- If the unit appears in a previous regular with_clause, the regular
4747 -- entities of the public part of the withed package must be replaced
4748 -- by the shadow ones.
4750 -- This code must be kept synchronized with the code that replaces the
4751 -- shadow entities by the real entities (see body of Remove_Limited
4752 -- With_Clause); otherwise the contents of the homonym chains are not
4753 -- consistent.
4755 else
4756 -- Hide all the type entities of the public part of the package to
4757 -- avoid its usage. This is needed to cover all the subtype decla-
4758 -- rations because we do not remove them from the homonym chain.
4770 -- Replace the real entities by the shadow entities of the limited
4771 -- view. The first element of the limited view is a header that is
4772 -- used to reference the first shadow entity in the private part
4773 -- of the package. Successive elements are the limited views of the
4774 -- type (including regular incomplete types) declared in the package.
4781 loop
4784 -- Do not unchain nested packages and child units
4788 then
4789 declare
4792 begin
4796 -- Replace E in the homonyms list, so that the limited view
4797 -- becomes available.
4803 else
4804 loop
4807 -- E may have been removed when installing a previous
4808 -- limited_with_clause.
4827 Write_Eol;
4835 -- The package must be visible while the limited-with clause is active
4836 -- because references to the type P.T must resolve in the usual way.
4837 -- In addition, we remember that the limited-view has been installed to
4838 -- uninstall it at the point of context removal.
4843 -- If unit has not been analyzed in some previous context, check
4844 -- (imperfectly ???) whether it might need a body.
4847 Check_Body_Required;
4850 -- If the package in the limited_with clause is a child unit, the clause
4851 -- is unanalyzed and appears as a selected component. Recast it as an
4852 -- expanded name so that the entity can be properly set. Use entity of
4853 -- parent, if available, for higher ancestors in the name.
4856 declare
4860 begin
4865 loop
4868 -- Set entity of parent identifiers if the unit is a child
4869 -- unit. This ensures that the tree is properly formed from
4870 -- semantic point of view (e.g. for ASIS queries).
4877 -- Set entity of last ancestor
4890 -------------------------
4891 -- Install_Withed_Unit --
4892 -------------------------
4894 procedure Install_Withed_Unit
4897 is
4901 begin
4902 -- Ada 2005 (AI-262): Do not install the private withed unit if we are
4903 -- compiling a package declaration and the Private_With_OK flag was not
4904 -- set by the caller. These declarations will be installed later (before
4905 -- analyzing the private part of the package).
4910 then
4917 else
4922 Write_Eol;
4925 -- We do not apply the restrictions to an internal unit unless we are
4926 -- compiling the internal unit as a main unit. This check is also
4927 -- skipped for dummy units (for missing packages).
4932 then
4933 Check_Restricted_Unit
4939 -- If the unit is not analyzed after analysis of the with clause and
4940 -- it is an instantiation then it awaits a body and is the main unit.
4941 -- Its appearance in the context of some other unit indicates a
4942 -- circular dependency (DEC suite perversity).
4946 then
4947 Error_Msg_N
4953 -- If the child unit appears in the context of its parent, it is
4954 -- immediately visible.
4962 then
4963 -- Set flag as well on the visible entity that denotes the
4964 -- instance, which renames the current one.
4966 Set_Is_Visible_Child_Unit
4967 (Related_Instance
4971 -- The parent unit may have been installed already, and may have
4972 -- appeared in a use clause.
4983 or else Private_With_OK
4984 then
4991 -- A with-clause overrides a with-type clause: there are no restric-
4992 -- tions on the use of package entities.
4998 -- Ada 2005 (AI-377): it is illegal for a with_clause to name a child
4999 -- unit if there is a visible homograph for it declared in the same
5000 -- declarative region. This pathological case can only arise when an
5001 -- instance I1 of a generic unit G1 has an explicit child unit I1.G2,
5002 -- G1 has a generic child also named G2, and the context includes with_
5003 -- clauses for both I1.G2 and for G1.G2, making an implicit declaration
5004 -- of I1.G2 visible as well. If the child unit is named Standard, do
5005 -- not apply the check to the Standard package itself.
5010 then
5011 declare
5017 begin
5021 loop
5027 then
5031 then
5033 Error_Msg_N
5036 With_Clause);
5042 then
5043 -- With_clause for child unit of instance appears before
5044 -- in the context. We want to place the error message on
5045 -- it, not on the generic child unit itself.
5047 declare
5050 begin
5058 Error_Msg_N
5061 Prev_Clause);
5073 -------------------
5074 -- Is_Child_Spec --
5075 -------------------
5080 begin
5091 ------------------------------------
5092 -- Is_Legal_Shadow_Entity_In_Body --
5093 ------------------------------------
5097 begin
5099 and then
5100 Has_With_Clause
5104 -----------------------
5105 -- Load_Needed_Body --
5106 -----------------------
5108 -- N is a generic unit named in a with clause, or else it is a unit that
5109 -- contains a generic unit or an inlined function. In order to perform an
5110 -- instantiation, the body of the unit must be present. If the unit itself
5111 -- is generic, we assume that an instantiation follows, and load & analyze
5112 -- the body unconditionally. This forces analysis of the spec as well.
5114 -- If the unit is not generic, but contains a generic unit, it is loaded on
5115 -- demand, at the point of instantiation (see ch12).
5122 -- The loading and analysis is done with style checks off
5124 begin
5130 Unum :=
5131 Load_Unit
5141 else
5147 Write_Eol;
5159 -------------------------
5160 -- Build_Limited_Views --
5161 -------------------------
5176 -- Add attributes of an incomplete type to a shadow entity. The same
5177 -- attributes are placed on the real entity, so that gigi receives
5178 -- a consistent view.
5181 -- Add attributes of a package entity to the entity in a package
5182 -- declaration
5184 procedure Decorate_Tagged_Type
5188 -- Set basic attributes of tagged type T, including its class_wide type.
5189 -- The parameters Loc, Scope are used to decorate the class_wide type.
5192 -- Construct list of shadow entities and attach it to entity of
5193 -- package that is mentioned in a limited_with clause.
5195 function New_Internal_Shadow_Entity
5199 -- Build a new internal entity and append it to the list of shadow
5200 -- entities available through the limited-header
5202 -----------------
5203 -- Build_Chain --
5204 -----------------
5211 begin
5215 -- For each library_package_declaration in the environment, there
5216 -- is an implicit declaration of a *limited view* of that library
5217 -- package. The limited view of a package contains:
5219 -- * For each nested package_declaration, a declaration of the
5220 -- limited view of that package, with the same defining-
5221 -- program-unit name.
5223 -- * For each type_declaration in the visible part, an incomplete
5224 -- type-declaration with the same defining_identifier, whose
5225 -- completion is the type_declaration. If the type_declaration
5226 -- is tagged, then the incomplete_type_declaration is tagged
5227 -- incomplete.
5229 -- The partial view is tagged if the declaration has the
5230 -- explicit keyword, or else if it is a type extension, both
5231 -- of which can be ascertained syntactically.
5234 Is_Tagged :=
5237 or else
5239 and then
5240 Present
5248 else
5253 -- Create shadow entity for type
5255 Lim_Typ :=
5256 New_Internal_Shadow_Entity
5267 else
5274 N_Incomplete_Type_Declaration,
5275 N_Task_Type_Declaration,
5276 N_Protected_Type_Declaration)
5277 then
5280 Is_Tagged :=
5282 N_Incomplete_Type_Declaration)
5288 else
5293 Lim_Typ :=
5294 New_Internal_Shadow_Entity
5305 else
5318 -- Create shadow entity for type
5320 Lim_Typ :=
5321 New_Internal_Shadow_Entity
5335 -- Local package
5337 declare
5340 begin
5348 Lim_Typ :=
5349 New_Internal_Shadow_Entity
5361 -- Note: The non_limited_view attribute is not used
5362 -- for local packages.
5364 Build_Chain
5374 ------------------------------
5375 -- Decorate_Incomplete_Type --
5376 ------------------------------
5379 begin
5389 --------------------------
5390 -- Decorate_Tagged_Type --
5391 --------------------------
5393 procedure Decorate_Tagged_Type
5397 is
5400 begin
5404 -- Build corresponding class_wide type, if not previously done
5406 -- Note: The class-wide entity is shared by the limited-view
5407 -- and the full-view.
5412 -- Set parent to be the same as the parent of the tagged type.
5413 -- We need a parent field set, and it is supposed to point to
5414 -- the declaration of the type. The tagged type declaration
5415 -- essentially declares two separate types, the tagged type
5416 -- itself and the corresponding class-wide type, so it is
5417 -- reasonable for the parent fields to point to the declaration
5418 -- in both cases.
5422 -- Set remaining fields of classwide type
5435 -- Link type to its class-wide type
5441 ------------------------------------
5442 -- Decorate_Package_Specification --
5443 ------------------------------------
5446 begin
5447 -- Place only the most basic attributes
5453 --------------------------------
5454 -- New_Internal_Shadow_Entity --
5455 --------------------------------
5457 function New_Internal_Shadow_Entity
5461 is
5464 begin
5477 -- Start of processing for Build_Limited_Views
5479 begin
5482 -- A library_item mentioned in a limited_with_clause is a package
5483 -- declaration, not a subprogram declaration, generic declaration,
5484 -- generic instantiation, or package renaming declaration.
5495 when N_Generic_Package_Declaration |
5496 N_Generic_Subprogram_Declaration =>
5525 -- Check if the chain is already built
5535 -- Build the header of the limited_view
5542 -- Create the auxiliary chain. All the shadow entities are appended to
5543 -- the list of entities of the limited-view header
5545 Build_Chain
5549 -- Save the last built shadow entity. It is needed later to set the
5550 -- reference to the first shadow entity in the private part
5554 -- Ada 2005 (AI-262): Add the limited view of the private declarations
5555 -- Required to give support to limited-private-with clauses
5561 Set_First_Private_Entity
5563 else
5564 Set_First_Private_Entity
5571 -------------------------------
5572 -- Check_Body_Needed_For_SAL --
5573 -------------------------------
5578 -- Determine whether use of entity E might require the presence of its
5579 -- body. For a package this requires a recursive traversal of all nested
5580 -- declarations.
5582 ---------------------------
5583 -- Entity_Needed_For_SAL --
5584 ---------------------------
5589 begin
5592 then
5599 and then
5602 then
5608 then
5620 else
5625 -- Start of processing for Check_Body_Needed_For_SAL
5627 begin
5630 N_Generic_Package_Declaration
5631 and then
5633 then
5641 N_Subprogram_Declaration
5643 then
5647 Check_Body_Needed_For_SAL
5652 then
5657 then
5658 Check_Body_Needed_For_SAL
5663 --------------------
5664 -- Remove_Context --
5665 --------------------
5670 begin
5671 -- If this is a child unit, first remove the parent units
5680 ----------------------------
5681 -- Remove_Context_Clauses --
5682 ----------------------------
5688 begin
5689 -- Ada 2005 (AI-50217): We remove the context clauses in two phases:
5690 -- limited-views first and regular-views later (to maintain the
5691 -- stack model).
5693 -- First Phase: Remove limited_with context clauses
5698 -- We are interested only in with clauses which got installed
5699 -- on entry.
5704 then
5711 -- Second Phase: Loop through context items and undo regular
5712 -- with_clauses and use_clauses.
5717 -- We are interested only in with clauses which got installed on
5718 -- entry, as indicated by their Context_Installed flag set
5723 then
5728 then
5729 -- Remove items from one with'ed unit
5746 --------------------------------
5747 -- Remove_Limited_With_Clause --
5748 --------------------------------
5758 begin
5761 -- In case of limited with_clause on subprograms, generics, instances,
5762 -- or renamings, the corresponding error was previously posted and we
5763 -- have nothing to do here.
5771 -- Handle child packages
5781 Write_Eol;
5784 -- Prepare the removal of the shadow entities from visibility. The first
5785 -- element of the limited view is a header (an E_Package entity) that is
5786 -- used to reference the first shadow entity in the private part of the
5787 -- package
5792 -- Remove package and shadow entities from visibility if it has not
5793 -- been analyzed
5804 -- Otherwise this package has already appeared in the closure and its
5805 -- shadow entities must be replaced by its real entities. This code
5806 -- must be kept synchronized with the complementary code in Install
5807 -- Limited_Withed_Unit.
5809 else
5810 -- Real entities that are type or subtype declarations were hidden
5811 -- from visibility at the point of installation of the limited-view.
5812 -- Now we recover the previous value of the hidden attribute.
5825 loop
5826 -- Nested packages and child units were not unchained
5830 then
5831 -- If the package has incomplete types, the limited view of the
5832 -- incomplete type is in fact never visible (AI05-129) but we
5833 -- have created a shadow entity E1 for it, that points to E2,
5834 -- a non-limited incomplete type. This in turn has a full view
5835 -- E3 that is the full declaration. There is a corresponding
5836 -- shadow entity E4. When reinstalling the non-limited view,
5837 -- E2 must become the current entity and E3 must be ignored.
5844 then
5846 -- Lim_Typ is the limited view of a full type declaration
5847 -- that has a previous incomplete declaration, i.e. E3 from
5848 -- the previous description. Nothing to insert.
5852 else
5860 else
5863 loop
5872 -- Preserve structure of homonym chain
5882 -- Indicate that the limited view of the package is not installed
5888 --------------------
5889 -- Remove_Parents --
5890 --------------------
5900 begin
5906 then
5917 -- Remove from visibility the siblings as well, which are directly
5918 -- visible while the parent is in scope.
5931 -- This is the recursive call to remove the context of any higher
5932 -- level parent. This recursion ensures that all parents are removed
5933 -- in the reverse order of their installation.
5939 ---------------------------------
5940 -- Remove_Private_With_Clauses --
5941 ---------------------------------
5947 -- Check whether a given unit appears in a regular with_clause. Used to
5948 -- determine whether a private_with_clause, implicit or explicit, should
5949 -- be ignored.
5951 ----------------------------
5952 -- In_Regular_With_Clause --
5953 ----------------------------
5956 is
5959 begin
5965 then
5974 -- Start of processing for Remove_Private_With_Clauses
5976 begin
5981 then
5982 -- If private_with_clause is redundant, remove it from context,
5983 -- as a small optimization to subsequent handling of private_with
5984 -- clauses in other nested packages.
5987 declare
5989 begin
6001 else
6007 else
6013 ---------------------------------
6014 -- Remove_Unit_From_Visibility --
6015 ---------------------------------
6020 begin
6025 Write_Eol;
6036 --------
6037 -- sm --
6038 --------
6041 begin
6045 -------------
6046 -- Unchain --
6047 -------------
6052 begin
6061 else
6064 loop
6076 Write_Eol;