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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) 1992-2013, 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 ------------------------------------------------------------------------------
73 -----------------------
74 -- Local Subprograms --
75 -----------------------
78 -- Analyzes items in the context clause of compilation unit
81 -- Build and decorate the list of shadow entities for a package mentioned
82 -- in a limited_with clause. If the package was not previously analyzed
83 -- then it also performs a basic decoration of the real entities. This is
84 -- required in order to avoid passing non-decorated entities to the
85 -- back-end. Implements Ada 2005 (AI-50217).
88 -- Check whether the source for the body of a compilation unit must be
89 -- included in a standalone library.
92 -- If a with_clause mentions a private child unit, the compilation unit
93 -- must be a member of the same family, as described in 10.1.2.
96 -- Verify that a stub is declared immediately within a compilation unit,
97 -- and not in an inner frame.
100 -- When a child unit appears in a context clause, the implicit withs on
101 -- parents are made explicit, and with clauses are inserted in the context
102 -- clause before the one for the child. If a parent in the with_clause
103 -- is a renaming, the implicit with_clause is on the renaming whose name
104 -- is mentioned in the with_clause, and not on the package it renames.
105 -- N is the compilation unit whose list of context items receives the
106 -- implicit with_clauses.
109 -- Get defining entity of parent unit of a child unit. In most cases this
110 -- is the defining entity of the unit, but for a child instance whose
111 -- parent needs a body for inlining, the instantiation node of the parent
112 -- has not yet been rewritten as a package declaration, and the entity has
113 -- to be retrieved from the Instance_Spec of the unit.
115 function Has_With_Clause
119 -- Determine whether compilation unit C_Unit contains a [limited] with
120 -- clause for package Pack. Use the flag Is_Limited to designate desired
121 -- clause kind.
124 -- If the main unit is a child unit, implicit withs are also added for
125 -- all its ancestors.
128 -- Check that the shadow entity is not already in the homonym chain, for
129 -- example through a limited_with clause in a parent unit.
132 -- Subsidiary to Install_Context and Install_Parents. Process all with
133 -- and use clauses for current unit and its library unit if any.
136 -- Subsidiary to Install_Context. Process only limited with_clauses for
137 -- current unit. Implements Ada 2005 (AI-50217).
140 -- Place shadow entities for a limited_with package in the visibility
141 -- structures for the current compilation. Implements Ada 2005 (AI-50217).
143 procedure Install_Withed_Unit
146 -- If the unit is not a child unit, make unit immediately visible. The
147 -- caller ensures that the unit is not already currently installed. The
148 -- flag Private_With_OK is set true in Install_Private_With_Clauses, which
149 -- is called when compiling the private part of a package, or installing
150 -- the private declarations of a parent unit.
153 -- This procedure establishes the context for the compilation of a child
154 -- unit. If Lib_Unit is a child library spec then the context of the parent
155 -- is installed, and the parent itself made immediately visible, so that
156 -- the child unit is processed in the declarative region of the parent.
157 -- Install_Parents makes a recursive call to itself to ensure that all
158 -- parents are loaded in the nested case. If Lib_Unit is a library body,
159 -- the only effect of Install_Parents is to install the private decls of
160 -- the parents, because the visible parent declarations will have been
161 -- installed as part of the context of the corresponding spec.
164 -- In the compilation of a child unit, a child of any of the ancestor
165 -- units is directly visible if it is visible, because the parent is in
166 -- an enclosing scope. Iterate over context to find child units of U_Name
167 -- or of some ancestor of it.
170 -- When compiling a unit Q descended from some parent unit P, a limited
171 -- with_clause in the context of P that names some other ancestor of Q
172 -- must not be installed because the ancestor is immediately visible.
175 -- Lib_Unit is a library unit which may be a spec or a body. Is_Child_Spec
176 -- returns True if Lib_Unit is a library spec which is a child spec, i.e.
177 -- a library spec that has a parent. If the call to Is_Child_Spec returns
178 -- True, then Parent_Spec (Lib_Unit) is non-Empty and points to the
179 -- compilation unit for the parent spec.
180 --
181 -- Lib_Unit can also be a subprogram body that acts as its own spec. If the
182 -- Parent_Spec is non-empty, this is also a child unit.
185 -- Subsidiary of previous one. Remove use_ and with_clauses
188 -- Remove from visibility the shadow entities introduced for a package
189 -- mentioned in a limited_with clause. Implements Ada 2005 (AI-50217).
192 -- Remove_Parents checks if Lib_Unit is a child spec. If so then the parent
193 -- contexts established by the corresponding call to Install_Parents are
194 -- removed. Remove_Parents contains a recursive call to itself to ensure
195 -- that all parents are removed in the nested case.
198 -- Reset all visibility flags on unit after compiling it, either as a main
199 -- unit or as a unit in the context.
202 -- Remove single entity from visibility list
205 -- Common processing for all stubs (subprograms, tasks, packages, and
206 -- protected cases). N is the stub to be analyzed. Once the subunit name
207 -- is established, load and analyze. Nam is the non-overloadable entity
208 -- for which the proper body provides a completion. Subprogram stubs are
209 -- handled differently because they can be declarations.
212 -- A dummy procedure, for debugging use, called just before analyzing the
213 -- main unit (after dealing with any context clauses).
215 --------------------------
216 -- Limited_With_Clauses --
217 --------------------------
219 -- Limited_With clauses are the mechanism chosen for Ada 2005 to support
220 -- mutually recursive types declared in different units. A limited_with
221 -- clause that names package P in the context of unit U makes the types
222 -- declared in the visible part of P available within U, but with the
223 -- restriction that these types can only be used as incomplete types.
224 -- The limited_with clause does not impose a semantic dependence on P,
225 -- and it is possible for two packages to have limited_with_clauses on
226 -- each other without creating an elaboration circularity.
228 -- To support this feature, the analysis of a limited_with clause must
229 -- create an abbreviated view of the package, without performing any
230 -- semantic analysis on it. This "package abstract" contains shadow types
231 -- that are in one-one correspondence with the real types in the package,
232 -- and that have the properties of incomplete types.
234 -- The implementation creates two element lists: one to chain the shadow
235 -- entities, and one to chain the corresponding type entities in the tree
236 -- of the package. Links between corresponding entities in both chains
237 -- allow the compiler to select the proper view of a given type, depending
238 -- on the context. Note that in contrast with the handling of private
239 -- types, the limited view and the non-limited view of a type are treated
240 -- as separate entities, and no entity exchange needs to take place, which
241 -- makes the implementation must simpler than could be feared.
243 ------------------------------
244 -- Analyze_Compilation_Unit --
245 ------------------------------
255 procedure Check_Redundant_Withs
258 -- Determine whether the context list of a compilation unit contains
259 -- redundant with clauses. When checking body clauses against spec
260 -- clauses, set Context_Items to the context list of the body and
261 -- Spec_Context_Items to that of the spec. Parent packages are not
262 -- examined for documentation purposes.
265 -- Generate cross-reference information for the parents of child units.
266 -- N is a defining_program_unit_name, and P_Id is the immediate parent.
268 ---------------------------
269 -- Check_Redundant_Withs --
270 ---------------------------
272 procedure Check_Redundant_Withs
275 is
278 procedure Process_Body_Clauses
283 -- Examine the context clauses of a package body, trying to match the
284 -- name entity of Clause with any list element. If the match occurs
285 -- on a use package clause set Used to True, for a use type clause or
286 -- pragma Elaborate[_All], set Used_Type_Or_Elab to True.
288 procedure Process_Spec_Clauses
294 -- Examine the context clauses of a package spec, trying to match
295 -- the name entity of Clause with any list element. If the match
296 -- occurs on a use package clause, set Used to True, for a with
297 -- package clause other than Clause, set Withed to True. Limited
298 -- with clauses, implicitly generated with clauses and withs
299 -- having pragmas Elaborate or Elaborate_All applied to them are
300 -- skipped. Exit_On_Self is used to control the search loop and
301 -- force an exit whenever Clause sees itself in the search.
303 --------------------------
304 -- Process_Body_Clauses --
305 --------------------------
307 procedure Process_Body_Clauses
312 is
320 -- In an expanded name in a use clause, if the prefix is a renamed
321 -- package, the entity is set to the original package as a result,
322 -- when checking whether the package appears in a previous with
323 -- clause, the renaming has to be taken into account, to prevent
324 -- spurious/incorrect warnings. A common case is use of Text_IO.
326 ---------------
327 -- Same_Unit --
328 ---------------
331 begin
337 -- Start of processing for Process_Body_Clauses
339 begin
346 -- Package use clause
349 and then not Used
350 then
351 -- Search through use clauses
356 -- Case of a direct use of the one we are looking for
361 -- Handle nested case, as in "with P; use P.Q.R"
363 else
364 declare
367 begin
368 -- Loop through prefixes looking for match
385 -- USE TYPE clause
388 and then not Used_Type_Or_Elab
389 then
392 and then not Used_Type_Or_Elab
393 loop
401 -- Pragma Elaborate or Elaborate_All
404 and then
406 Name_Elaborate_All)
407 and then not Used_Type_Or_Elab
408 then
409 Prag_Unit :=
424 --------------------------
425 -- Process_Spec_Clauses --
426 --------------------------
428 procedure Process_Spec_Clauses
434 is
439 begin
446 -- Stop the search since the context items after Cont_Item have
447 -- already been examined in a previous iteration of the reverse
448 -- loop in Check_Redundant_Withs.
450 if Exit_On_Self
452 then
456 -- Package use clause
459 and then not Used
460 then
470 -- Package with clause. Avoid processing self, implicitly
471 -- generated with clauses or limited with clauses. Note that
472 -- we examine with clauses having pragmas Elaborate or
473 -- Elaborate_All applied to them due to cases such as:
475 -- with Pack;
476 -- with Pack;
477 -- pragma Elaborate (Pack);
479 -- In this case, the second with clause is redundant since
480 -- the pragma applies only to the first "with Pack;".
482 -- Note that we only consider with_clauses that comes from
483 -- source. In the case of renamings used as prefixes of names
484 -- in with_clauses, we generate a with_clause for the prefix,
485 -- which we do not treat as implicit because it is needed for
486 -- visibility analysis, but is also not redundant.
494 then
502 -- Start of processing for Check_Redundant_Withs
504 begin
508 -- Avoid checking implicitly generated with clauses, limited with
509 -- clauses or withs that have pragma Elaborate or Elaborate_All.
515 then
516 -- Package body-to-spec check
519 declare
525 begin
526 Process_Spec_Clauses
532 Process_Body_Clauses
538 -- "Type Elab" refers to the presence of either a use
539 -- type clause, pragmas Elaborate or Elaborate_All.
541 -- +---------------+---------------------------+------+
542 -- | Spec | Body | Warn |
543 -- +--------+------+--------+------+-----------+------+
544 -- | Withed | Used | Withed | Used | Type Elab | |
545 -- | X | | X | | | X |
546 -- | X | | X | X | | |
547 -- | X | | X | | X | |
548 -- | X | | X | X | X | |
549 -- | X | X | X | | | X |
550 -- | X | X | X | | X | |
551 -- | X | X | X | X | | X |
552 -- | X | X | X | X | X | |
553 -- +--------+------+--------+------+-----------+------+
557 and then
560 then
561 Error_Msg_N -- CODEFIX
571 -- Standalone package spec or body check
573 else
574 declare
578 begin
579 -- The mechanism for examining the context clauses of a
580 -- package spec can be applied to package body clauses.
582 Process_Spec_Clauses
590 Error_Msg_N -- CODEFIX
601 --------------------------------
602 -- Generate_Parent_References --
603 --------------------------------
609 begin
614 -- Done already, if the unit has been compiled indirectly as
615 -- part of the closure of its context because of inlining.
629 -- The guard here on P_Name is to handle the error condition where
630 -- the parent unit is missing because the file was not found.
640 -- Start of processing for Analyze_Compilation_Unit
642 begin
645 -- If the unit is a subunit whose parent has not been analyzed (which
646 -- indicates that the main unit is a subunit, either the current one or
647 -- one of its descendents) then the subunit is compiled as part of the
648 -- analysis of the parent, which we proceed to do. Basically this gets
649 -- handled from the top down and we don't want to do anything at this
650 -- level (i.e. this subunit will be handled on the way down from the
651 -- parent), so at this level we immediately return. If the subunit ends
652 -- up not analyzed, it means that the parent did not contain a stub for
653 -- it, or that there errors were detected in some ancestor.
661 else
669 -- Analyze context (this will call Sem recursively for with'ed units) To
670 -- detect circularities among with-clauses that are not caught during
671 -- loading, we set the Context_Pending flag on the current unit. If the
672 -- flag is already set there is a potential circularity. We exclude
673 -- predefined units from this check because they are known to be safe.
674 -- We also exclude package bodies that are present because circularities
675 -- between bodies are harmless (and necessary).
678 declare
681 begin
682 if Is_Predefined_File_Name
684 then
687 else
691 then
700 Error_Msg_N
714 else
722 -- If the unit is a package body, the spec is already loaded and must be
723 -- analyzed first, before we analyze the body.
727 -- If no Lib_Unit, then there was a serious previous error, so just
728 -- ignore the entire analysis effort
731 Check_Error_Detected;
734 else
735 -- Analyze the package spec
739 -- Check for unused with's
743 -- Verify that the library unit is a package declaration
746 N_Generic_Package_Declaration)
747 then
748 Error_Msg_N
752 -- Otherwise, the entity in the declaration is visible. Update the
753 -- version to reflect dependence of this body on the spec.
755 else
761 N_Defining_Program_Unit_Name
762 then
768 -- If the unit is a subprogram body, then we similarly need to analyze
769 -- its spec. However, things are a little simpler in this case, because
770 -- here, this analysis is done mostly for error checking and consistency
771 -- purposes (but not only, e.g. there could be a contract on the spec),
772 -- so there's nothing else to be done.
777 -- If the subprogram body is a child unit, we must create a
778 -- declaration for it, in order to properly load the parent(s).
779 -- After this, the original unit does not acts as a spec, because
780 -- there is an explicit one. If this unit appears in a context
781 -- clause, then an implicit with on the parent will be added when
782 -- installing the context. If this is the main unit, there is no
783 -- Unit_Table entry for the declaration (it has the unit number
784 -- of the main unit) and code generation is unaffected.
790 Unum :=
791 Load_Unit
799 -- Build subprogram declaration and attach parent unit to it
800 -- This subprogram declaration does not come from source,
801 -- Nevertheless the backend must generate debugging info for
802 -- it, and this must be indicated explicitly. We also mark
803 -- the body entity as a child unit now, to prevent a
804 -- cascaded error if the spec entity cannot be entered
805 -- in its scope. Finally we create a Units table entry for
806 -- the subprogram declaration, to maintain a one-to-one
807 -- correspondence with compilation unit nodes. This is
808 -- critical for the tree traversals performed by CodePeer.
810 declare
813 Get_Comes_From_Source_Default;
815 begin
818 -- Checks for redundant USE TYPE clauses have a special
819 -- exception for the synthetic spec we create here. This
820 -- special case relies on the two compilation units
821 -- sharing the same context clause.
823 -- Note: We used to do a shallow copy (New_Copy_List),
824 -- which defeated those checks and also created malformed
825 -- trees (subtype mark shared by two distinct
826 -- N_Use_Type_Clause nodes) which crashed the compiler.
828 Lib_Unit :=
831 Unit =>
833 Specification =>
834 Copy_Separate_Tree
836 Aux_Decls_Node =>
844 -- Now that a separate declaration exists, the body
845 -- of the child unit does not act as spec any longer.
855 -- Here for subprogram with separate declaration
857 else
863 -- If this is a child unit, generate references to the parents
866 N_Defining_Program_Unit_Name
867 then
868 Generate_Parent_References (
874 -- If it is a child unit, the parent must be elaborated first and we
875 -- update version, since we are dependent on our parent.
879 -- The analysis of the parent is done with style checks off
881 declare
884 begin
892 -- Restore style check settings
898 -- With the analysis done, install the context. Note that we can't
899 -- install the context from the with clauses as we analyze them, because
900 -- each with clause must be analyzed in a clean visibility context, so
901 -- we have to wait and install them all at once.
907 -- Set the entities of all parents in the program_unit_name
909 Generate_Parent_References (
913 -- All components of the context: with-clauses, library unit, ancestors
914 -- if any, (and their context) are analyzed and installed.
916 -- Call special debug routine sm if this is the main unit
919 sm;
922 -- Now analyze the unit (package, subprogram spec, body) itself
930 Check_Redundant_Withs
936 -- The above call might have made Unit_Node an N_Subprogram_Body from
937 -- something else, so propagate any Acts_As_Spec flag.
941 then
945 -- Register predefined units in Rtsfind
947 declare
949 begin
955 -- Treat compilation unit pragmas that appear after the library unit
958 declare
960 begin
968 -- Generate distribution stubs if requested and no error
972 or else
975 then
978 -- Regular RCI package
986 and then
988 then
989 -- Shared passive package
994 and then
995 Is_Remote_Call_Interface
997 then
998 -- Instantiation of a RCI generic package
1004 -- Remove unit from visibility, so that environment is clean for the
1005 -- next compilation, which is either the main unit or some other unit
1006 -- in the context.
1009 N_Package_Renaming_Declaration,
1010 N_Subprogram_Declaration)
1014 then
1017 -- If the unit is an instantiation whose body will be elaborated for
1018 -- inlining purposes, use the proper entity of the instance. The entity
1019 -- may be missing if the instantiation was illegal.
1024 then
1025 Remove_Unit_From_Visibility
1031 then
1032 -- Bodies that are not the main unit are compiled if they are generic
1033 -- or contain generic or inlined units. Their analysis brings in the
1034 -- context of the corresponding spec (unit declaration) which must be
1035 -- removed as well, to return the compilation environment to its
1036 -- proper state.
1042 -- Last step is to deinstall the context we just installed as well as
1043 -- the unit just compiled.
1047 -- If this is the main unit and we are generating code, we must check
1048 -- that all generic units in the context have a body if they need it,
1049 -- even if they have not been instantiated. In the absence of .ali files
1050 -- for generic units, we must force the load of the body, just to
1051 -- produce the proper error if the body is absent. We skip this
1052 -- verification if the main unit itself is generic.
1056 and then Expander_Active
1057 then
1058 -- Check whether the source for the body of the unit must be included
1059 -- in a standalone library.
1063 -- Indicate that the main unit is now analyzed, to catch possible
1064 -- circularities between it and generic bodies. Remove main unit from
1065 -- visibility. This might seem superfluous, but the main unit must
1066 -- not be visible in the generic body expansions that follow.
1071 declare
1078 begin
1082 -- Check for explicit with clause
1087 -- Ada 2005 (AI-50217): Ignore limited-withed units
1090 then
1093 -- Compile generic subprogram, unless it is intrinsic or
1094 -- imported so no body is required, or generic package body
1095 -- if the package spec requires a body.
1102 then
1106 Un :=
1107 Load_Unit
1109 (Get_Unit_Name
1110 (Unit_Declaration_Node
1116 else
1117 Un :=
1118 Load_Unit
1128 Error_Msg_NE
1135 then
1145 -- Restore style checks settings
1151 -- Deal with creating elaboration Boolean if needed. We create an
1152 -- elaboration boolean only for units that come from source since
1153 -- units manufactured by the compiler never need elab checks.
1157 N_Generic_Package_Declaration,
1158 N_Subprogram_Declaration,
1159 N_Generic_Subprogram_Declaration)
1160 then
1161 declare
1165 begin
1169 -- See if an elaboration entity is required for possible access
1170 -- before elaboration checking. Note that we must allow for this
1171 -- even if -gnatE is not set, since a client may be compiled in
1172 -- -gnatE mode and reference the entity.
1174 -- These entities are also used by the binder to prevent multiple
1175 -- attempts to execute the elaboration code for the library case
1176 -- where the elaboration routine might otherwise be called more
1177 -- than once.
1179 -- Case of units which do not require elaboration checks
1181 if
1182 -- Pure units do not need checks
1186 -- Preelaborated units do not need checks
1190 -- No checks needed if pragma Elaborate_Body present
1194 -- No checks needed if unit does not require a body
1198 -- No checks needed for predefined files
1202 -- No checks required if no separate spec
1205 then
1206 -- This is a case where we only need the entity for
1207 -- checking to prevent multiple elaboration checks.
1211 -- Case of elaboration entity is required for access before
1212 -- elaboration checking (so certainly we must build it!)
1214 else
1222 -- Freeze the compilation unit entity. This for sure is needed because
1223 -- of some warnings that can be output (see Freeze_Subprogram), but may
1224 -- in general be required. If freezing actions result, place them in the
1225 -- compilation unit actions list, and analyze them.
1227 declare
1230 begin
1240 and then Expander_Active
1241 then
1242 declare
1247 begin
1249 Reset_Style_Check_Options;
1253 Reset_Style_Check_Options;
1260 -- If we are generating obsolescent warnings, then here is where we
1261 -- generate them for the with'ed items. The reason for this special
1262 -- processing is that the normal mechanism of generating the warnings
1263 -- for referenced entities does not work for context clause references.
1264 -- That's because when we first analyze the context, it is too early to
1265 -- know if the with'ing unit is itself obsolescent (which suppresses
1266 -- the warnings).
1268 if not GNAT_Mode
1269 and then Warn_On_Obsolescent_Feature
1271 then
1272 -- Push current compilation unit as scope, so that the test for
1273 -- being within an obsolescent unit will work correctly. The check
1274 -- is not performed within an instantiation, because the warning
1275 -- will have been emitted in the corresponding generic unit.
1279 -- Loop through context items to deal with with clauses
1281 declare
1286 begin
1291 -- Suppress this check in limited-withed units. Further work
1292 -- needed here if we decide to incorporate this check on
1293 -- limited-withed units.
1296 then
1309 -- Remove temporary install of current unit as scope
1311 Pop_Scope;
1315 ---------------------
1316 -- Analyze_Context --
1317 ---------------------
1323 begin
1324 -- First process all configuration pragmas at the start of the context
1325 -- items. Strictly these are not part of the context clause, but that
1326 -- is where the parser puts them. In any case for sure we must analyze
1327 -- these before analyzing the actual context items, since they can have
1328 -- an effect on that analysis (e.g. pragma Ada_2005 may allow a unit to
1329 -- be with'ed as a result of changing categorizations in Ada 2005).
1335 loop
1340 -- This is the point at which we capture the configuration settings
1341 -- for the unit. At the moment only the Optimize_Alignment setting
1342 -- needs to be captured. Probably more later ???
1346 else
1350 -- Loop through actual context items. This is done in two passes:
1352 -- a) The first pass analyzes non-limited with-clauses and also any
1353 -- configuration pragmas (we need to get the latter analyzed right
1354 -- away, since they can affect processing of subsequent items.
1356 -- b) The second pass analyzes limited_with clauses (Ada 2005: AI-50217)
1360 -- For with clause, analyze the with clause, and then update the
1361 -- version, since we are dependent on a unit that we with.
1365 then
1366 -- Skip analyzing with clause if no unit, nothing to do (this
1367 -- happens for a with that references a non-existent unit). Skip
1368 -- as well if this is a with_clause for the main unit, which
1369 -- happens if a subunit has a useless with_clause on its parent.
1375 else
1384 -- Skip pragmas. Configuration pragmas at the start were handled in
1385 -- the loop above, and remaining pragmas are not processed until we
1386 -- actually install the context (see Install_Context). We delay the
1387 -- analysis of these pragmas to make sure that we have installed all
1388 -- the implicit with's on parent units.
1390 -- Skip use clauses at this stage, since we don't want to do any
1391 -- installing of potentially use-visible entities until we
1392 -- actually install the complete context (in Install_Context).
1393 -- Otherwise things can get installed in the wrong context.
1395 else
1402 -- Second pass: examine all limited_with clauses. All other context
1403 -- items are ignored in this pass.
1409 then
1410 -- No need to check errors on implicitly generated limited-with
1411 -- clauses.
1415 -- Verify that the illegal contexts given in 10.1.2 (18/2) are
1416 -- properly rejected, including renaming declarations.
1419 N_Subprogram_Declaration)
1422 then
1425 -- Check wrong use of a limited with clause applied to the
1426 -- compilation unit containing the limited-with clause.
1428 -- limited with P.Q;
1429 -- package P.Q is ...
1434 -- Check wrong use of limited-with clause applied to some
1435 -- immediate ancestor.
1438 declare
1442 begin
1444 loop
1457 -- Check if the limited-withed unit is already visible through
1458 -- some context clause of the current compilation unit or some
1459 -- ancestor of the current compilation unit.
1461 declare
1467 begin
1469 loop
1475 and then
1477 N_Package_Declaration,
1478 N_Package_Renaming_Declaration)
1479 then
1481 N_Package_Declaration
1482 then
1484 else
1488 -- Check if the named package (or some ancestor)
1489 -- leaves visible the full-view of the unit given
1490 -- in the limited-with clause
1492 loop
1494 Unit_Name)
1495 then
1497 Error_Msg_N
1500 Item);
1501 Error_Msg_NE
1525 -- Skip analyzing with clause if no unit, see above
1531 -- A limited_with does not impose an elaboration order, but
1532 -- there is a semantic dependency for recompilation purposes.
1538 -- Pragmas and use clauses and with clauses other than limited
1539 -- with's are ignored in this pass through the context items.
1541 else
1549 -------------------------------
1550 -- Analyze_Package_Body_Stub --
1551 -------------------------------
1557 begin
1558 -- The package declaration must be in the current declarative part
1568 then
1571 else
1572 -- Indicate that the body of the package exists. If we are doing
1573 -- only semantic analysis, the stub stands for the body. If we are
1574 -- generating code, the existence of the body will be confirmed
1575 -- when we load the proper body.
1585 -------------------------
1586 -- Analyze_Proper_Body --
1587 -------------------------
1594 -- This procedure is called when the main unit is a stub, or when we
1595 -- are not generating code. In such a case, we analyze the subunit if
1596 -- present, which is user-friendly and in fact required for ASIS, but
1597 -- we don't complain if the subunit is missing.
1599 ----------------------
1600 -- Optional_Subunit --
1601 ----------------------
1606 begin
1607 -- Try to load subunit, but ignore any errors that occur during the
1608 -- loading of the subunit, by using the special feature in Errout to
1609 -- ignore all errors. Note that Fatal_Error will still be set, so we
1610 -- will be able to check for this case below.
1616 Unum :=
1617 Load_Unit
1627 -- All done if we successfully loaded the subunit
1631 then
1634 -- If the file was empty or seriously mangled, the unit itself may
1635 -- be missing.
1638 Error_Msg_N
1642 Error_Msg_N
1645 else
1653 then
1656 else
1657 Set_Corresponding_Body (
1663 -- Local variables
1667 -- Start of processing for Analyze_Proper_Body
1669 begin
1670 -- If the subunit is already loaded, it means that the main unit is a
1671 -- subunit, and that the current unit is one of its parents which was
1672 -- being analyzed to provide the needed context for the analysis of the
1673 -- subunit. In this case we analyze the subunit and continue with the
1674 -- parent, without looking at subsequent subunits.
1678 -- If the proper body is already linked to the stub node, the stub is
1679 -- in a generic unit and just needs analyzing.
1684 -- If the subunit has severe errors, the spec of the enclosing
1685 -- body may not be available, in which case do not try analysis.
1689 then
1695 -- Otherwise we must load the subunit and link to it
1697 else
1698 -- Load the subunit, this must work, since we originally loaded
1699 -- the subunit earlier on. So this will not really load it, just
1700 -- give access to it.
1702 Unum :=
1703 Load_Unit
1709 -- And analyze the subunit in the parent context (note that we
1710 -- do not call Semantics, since that would remove the parent
1711 -- context). Because of this, we have to manually reset the
1712 -- compiler state to Analyzing since it got destroyed by Load.
1717 -- Check that the proper body is a subunit and not a child
1718 -- unit. If the unit was previously loaded, the error will
1719 -- have been emitted when copying the generic node, so we
1720 -- just return to avoid cascaded errors.
1732 -- If the main unit is a subunit, then we are just performing semantic
1733 -- analysis on that subunit, and any other subunits of any parent unit
1734 -- should be ignored, except that if we are building trees for ASIS
1735 -- usage we want to annotate the stub properly.
1739 then
1741 Optional_Subunit;
1744 -- But before we return, set the flag for unloaded subunits. This
1745 -- will suppress junk warnings of variables in the same declarative
1746 -- part (or a higher level one) that are in danger of looking unused
1747 -- when in fact there might be a declaration in the subunit that we
1748 -- do not intend to load.
1753 -- If the subunit is not already loaded, and we are generating code,
1754 -- then this is the case where compilation started from the parent, and
1755 -- we are generating code for an entire subunit tree. In that case we
1756 -- definitely need to load the subunit.
1758 -- In order to continue the analysis with the rest of the parent,
1759 -- and other subunits, we load the unit without requiring its
1760 -- presence, and emit a warning if not found, rather than terminating
1761 -- the compilation abruptly, as for other missing file problems.
1765 -- If the proper body is already linked to the stub node, the stub is
1766 -- in a generic unit and just needs analyzing.
1768 -- We update the version. Although we are not strictly technically
1769 -- semantically dependent on the subunit, given our approach of macro
1770 -- substitution of subunits, it makes sense to include it in the
1771 -- version identification.
1778 -- Otherwise we must load the subunit and link to it
1780 else
1781 -- Make sure that, if the subunit is preprocessed and -gnateG is
1782 -- specified, the preprocessed file will be written.
1785 Unum :=
1786 Load_Unit
1793 -- Give message if we did not get the unit Emit warning even if
1794 -- missing subunit is not within main unit, to simplify debugging.
1798 then
1800 Error_Msg_File_1 :=
1802 Error_Msg_N
1807 -- Load_Unit may reset Compiler_State, since it may have been
1808 -- necessary to parse an additional units, so we make sure that
1809 -- we reset it to the Analyzing state.
1816 Write_Eol;
1819 declare
1823 begin
1824 -- Check for child unit instead of subunit
1827 Error_Msg_N
1831 -- OK, we have a subunit
1833 else
1836 -- Set corresponding stub (even if errors)
1840 -- Collect SCO information for loaded subunit if we are
1841 -- in the main unit.
1843 if Generate_SCO
1844 and then
1845 In_Extended_Main_Source_Unit
1847 then
1851 -- Propagate all aspect specifications associated with
1852 -- the stub to the proper body.
1856 -- Move all source pragmas that follow the body stub and
1857 -- apply to it to the declarations of the proper body.
1863 -- Analyze the unit if semantics active
1869 -- Set the library unit pointer in any case
1873 -- We update the version. Although we are not technically
1874 -- semantically dependent on the subunit, given our
1875 -- approach of macro substitution of subunits, it makes
1876 -- sense to include it in the version identification.
1882 -- The unit which should contain the proper subprogram body does
1883 -- not exist. Analyze the aspect specifications of the stub (if
1884 -- any).
1888 then
1891 -- Restore the proper visibility of the stub and its formals
1898 Pop_Scope;
1902 -- The remaining case is when the subunit is not already loaded and we
1903 -- are not generating code. In this case we are just performing semantic
1904 -- analysis on the parent, and we are not interested in the subunit. For
1905 -- subprograms, analyze the stub as a body. For other entities the stub
1906 -- has already been marked as completed.
1908 else
1909 Optional_Subunit;
1913 ----------------------------------
1914 -- Analyze_Protected_Body_Stub --
1915 ----------------------------------
1920 begin
1923 -- First occurrence of name may have been as an incomplete type
1932 else
1941 ----------------------------------
1942 -- Analyze_Subprogram_Body_Stub --
1943 ----------------------------------
1945 -- A subprogram body stub can appear with or without a previous spec. If
1946 -- there is one, then the analysis of the body will find it and verify
1947 -- conformance. The formals appearing in the specification of the stub play
1948 -- no role, except for requiring an additional conformance check. If there
1949 -- is no previous subprogram declaration, the stub acts as a spec, and
1950 -- provides the defining entity for the subprogram.
1955 begin
1958 -- Verify that the identifier for the stub is unique within this
1959 -- declarative part.
1962 N_Package_Body,
1963 N_Subprogram_Body)
1964 then
1970 then
1978 -- Treat stub as a body, which checks conformance if there is a previous
1979 -- declaration, or else introduces entity and its signature.
1985 ---------------------
1986 -- Analyze_Subunit --
1987 ---------------------
1989 -- A subunit is compiled either by itself (for semantic checking) or as
1990 -- part of compiling the parent (for code generation). In either case, by
1991 -- the time we actually process the subunit, the parent has already been
1992 -- installed and analyzed. The node N is a compilation unit, whose context
1993 -- needs to be treated here, because we come directly here from the parent
1994 -- without calling Analyze_Compilation_Unit.
1996 -- The compilation context includes the explicit context of the subunit,
1997 -- and the context of the parent, together with the parent itself. In order
1998 -- to compile the current context, we remove the one inherited from the
1999 -- parent, in order to have a clean visibility table. We restore the parent
2000 -- context before analyzing the proper body itself. On exit, we remove only
2001 -- the explicit context of the subunit.
2014 Cunit_Boolean_Restrictions_Save;
2015 -- Save non-partition wide restrictions before processing the subunit.
2016 -- All subunits are analyzed with config restrictions reset and we need
2017 -- to restore these saved values at the end.
2020 -- Capture names in use clauses of the subunit. This must be done before
2021 -- re-installing parent declarations, because items in the context must
2022 -- not be hidden by declarations local to the parent.
2025 -- Recursive procedure to restore scope of all ancestors of subunit,
2026 -- from outermost in. If parent is not a subunit, the call to install
2027 -- context installs context of spec and (if parent is a child unit) the
2028 -- context of its parents as well. It is confusing that parents should
2029 -- be treated differently in both cases, but the semantics are just not
2030 -- identical.
2033 -- As part of the removal of the parent scope, the use clauses are
2034 -- removed, to be reinstalled when the context of the subunit has been
2035 -- analyzed. Use clauses may also have been affected by the analysis of
2036 -- the context of the subunit, so they have to be applied again, to
2037 -- insure that the compilation environment of the rest of the parent
2038 -- unit is identical.
2041 -- Remove current scope from scope stack, and preserve the list of use
2042 -- clauses in it, to be reinstalled after context is analyzed.
2044 -----------------------------
2045 -- Analyze_Subunit_Context --
2046 -----------------------------
2053 begin
2056 -- Make withed units immediately visible. If child unit, make the
2057 -- ultimate parent immediately visible.
2063 -- Protect frontend against previous errors in context clauses
2069 else
2070 -- If a subunits has serious syntax errors, the context
2071 -- may not have been loaded. Add a harmless unit name to
2072 -- attempt processing.
2076 then
2081 loop
2087 Check_Error_Detected;
2117 -- Reset visibility of withed units. They will be made visible again
2118 -- when we install the subunit context.
2124 -- Protect frontend against previous errors in context clauses
2128 then
2130 loop
2146 ------------------------
2147 -- Re_Install_Parents --
2148 ------------------------
2153 begin
2160 -- If the subunit occurs within a child unit, we must restore the
2161 -- immediate visibility of any siblings that may occur in context.
2173 -- Make entities in scope visible again. For child units, restore
2174 -- visibility only if they are actually in context.
2185 -- A subunit appears within a body, and for a nested subunits all the
2186 -- parents are bodies. Restore full visibility of their private
2187 -- entities.
2195 ----------------------------
2196 -- Re_Install_Use_Clauses --
2197 ----------------------------
2201 begin
2209 ------------------
2210 -- Remove_Scope --
2211 ------------------
2216 begin
2231 Pop_Scope;
2234 -- Start of processing for Analyze_Subunit
2236 begin
2237 -- For subunit in main extended unit, we reset the configuration values
2238 -- for the non-partition-wide restrictions. For other units reset them.
2241 Restore_Config_Cunit_Boolean_Restrictions;
2242 else
2243 Reset_Cunit_Boolean_Restrictions;
2247 declare
2250 begin
2261 -- Save current use clauses
2263 Remove_Scope;
2266 -- Now remove parents and their context, including enclosing subunits
2267 -- and the outer parent body which is not a subunit.
2274 Remove_Scope;
2279 Remove_Scope;
2289 Analyze_Subunit_Context;
2294 -- If the context includes a child unit of the parent of the subunit,
2295 -- the parent will have been removed from visibility, after compiling
2296 -- that cousin in the context. The visibility of the parent must be
2297 -- restored now. This also applies if the context includes another
2298 -- subunit of the same parent which in turn includes a child unit in
2299 -- its context.
2304 and then not
2306 then
2313 Re_Install_Use_Clauses;
2316 -- Restore state of suppress flags for current body
2320 -- If the subunit is within a child unit, then siblings of any parent
2321 -- unit that appear in the context clause of the subunit must also be
2322 -- made immediately visible.
2332 -- The subunit may contain a with_clause on a sibling of some ancestor.
2333 -- Removing the context will remove from visibility those ancestor child
2334 -- units, which must be restored to the visibility they have in the
2335 -- enclosing body.
2338 declare
2340 begin
2350 -- Deal with restore of restrictions
2355 ----------------------------
2356 -- Analyze_Task_Body_Stub --
2357 ----------------------------
2363 begin
2366 -- First occurrence of name may have been as an incomplete type
2374 else
2379 -- Check for duplicate stub, if so give message and terminate
2384 else
2390 -- Set elaboration flag to indicate that entity is callable. This
2391 -- cannot be done in the expansion of the body itself, because the
2392 -- proper body is not in a declarative part. This is only done if
2393 -- expansion is active, because the context may be generic and the
2394 -- flag not defined yet.
2399 Name =>
2407 -------------------------
2408 -- Analyze_With_Clause --
2409 -------------------------
2411 -- Analyze the declaration of a unit in a with clause. At end, label the
2412 -- with clause with the defining entity for the unit.
2416 -- Retrieve the original kind of the unit node, before analysis. If it
2417 -- is a subprogram instantiation, its analysis below will rewrite the
2418 -- node as the declaration of the wrapper package. If the same
2419 -- instantiation appears indirectly elsewhere in the context, it will
2420 -- have been analyzed already.
2431 -- Set True if the unit currently being compiled is an internal unit
2434 -- Set True if a with violates a restriction, no point in giving any
2435 -- warnings if we have this definite error.
2439 begin
2442 -- If this is an internal unit which is a renaming, then this is a
2443 -- violation of No_Obsolescent_Features.
2445 -- Note: this is not quite right if the user defines one of these units
2446 -- himself, but that's a marginal case, and fixing it is hard ???
2449 declare
2452 begin
2454 and then not
2456 then
2463 -- Check No_Implementation_Units violation
2468 else
2474 -- Several actions are skipped for dummy packages (those supplied for
2475 -- with's where no matching file could be found). Such packages are
2476 -- identified by the Sloc value being set to No_Location.
2480 -- Ada 2005 (AI-50217): Build visibility structures but do not
2481 -- analyze the unit.
2490 -- If the library unit is a predefined unit, and we are in high
2491 -- integrity mode, then temporarily reset Configurable_Run_Time_Mode
2492 -- for the analysis of the with'ed unit. This mode does not prevent
2493 -- explicit with'ing of run-time units.
2495 if Configurable_Run_Time_Mode
2497 then
2502 else
2510 -- Check restrictions, except that we skip the check if this is an
2511 -- internal unit unless we are compiling the internal unit as the
2512 -- main unit. We also skip this for dummy packages.
2520 -- Deal with special case of GNAT.Current_Exceptions which interacts
2521 -- with the optimization of local raise statements into gotos.
2527 Name_Most_Recent_Exception,
2528 Name_Exception_Traces)
2529 then
2534 -- Check for inappropriate with of internal implementation unit if we
2535 -- are not compiling an internal unit and also check for withing unit
2536 -- in wrong version of Ada. Do not issue these messages for implicit
2537 -- with's generated by the compiler itself.
2539 if Implementation_Unit_Warnings
2540 and then not Intunit
2542 and then not Restriction_Violation
2543 then
2544 declare
2548 begin
2552 -- Add alternative name if available, otherwise issue a
2553 -- general warning message.
2557 else
2558 Error_Msg_F
2565 and then Warn_On_Ada_2005_Compatibility
2566 then
2571 and then Warn_On_Ada_2012_Compatibility
2572 then
2579 -- Semantic analysis of a generic unit is performed on a copy of
2580 -- the original tree. Retrieve the entity on which semantic info
2581 -- actually appears.
2586 -- Note: in the following test, Unit_Kind is the original Nkind, but in
2587 -- the case of an instantiation, semantic analysis above will have
2588 -- replaced the unit by its instantiated version. If the instance body
2589 -- has been generated, the instance now denotes the body entity. For
2590 -- visibility purposes we need the entity of its spec.
2594 N_Package_Instantiation)
2596 then
2602 then
2603 -- If the instance has not been rewritten as a package declaration,
2604 -- then it appeared already in a previous with clause. Retrieve
2605 -- the entity from the previous instance.
2611 -- The visible subprogram is created during instantiation, and is
2612 -- an attribute of the wrapper package. We retrieve the wrapper
2613 -- package directly from the instantiation node. If the instance
2614 -- is inlined the unit is still an instantiation. Otherwise it has
2615 -- been rewritten as the declaration of the wrapper itself.
2618 E_Name :=
2619 Related_Instance
2621 else
2627 then
2633 then
2634 -- For a child unit that has no spec, one has been created and
2635 -- analyzed. The entity required is that of the spec.
2639 else
2645 -- Child unit in a with clause
2649 -- If this is a child unit without a spec, and it has been analyzed
2650 -- already, a declaration has been created for it. The with_clause
2651 -- must reflect the actual body, and not the generated declaration,
2652 -- to prevent spurious binding errors involving an out-of-date spec.
2653 -- Note that this can only happen if the unit includes more than one
2654 -- with_clause for the child unit (e.g. in separate subunits).
2659 then
2665 -- Restore style checks
2669 -- Record the reference, but do NOT set the unit as referenced, we want
2670 -- to consider the unit as unreferenced if this is the only reference
2671 -- that occurs.
2676 -- Generate references and check No_Dependence restriction for parents
2685 and then
2688 then
2689 -- The prefix is a child unit that denotes a renaming declaration.
2690 -- Replace the prefix directly with the renamed unit, because the
2691 -- rest of the prefix is irrelevant to the visibility of the real
2692 -- unit.
2704 -- If E_Name is the dummy entity for a nonexistent unit, its scope
2705 -- is set to Standard_Standard, and no attempt should be made to
2706 -- further unwind scopes.
2712 -- Abandon processing in case of previous errors
2715 Check_Error_Detected;
2722 then
2723 -- If the entity is set without its unit being compiled, the
2724 -- original parent is a renaming, and Par_Name is the renamed
2725 -- entity. For visibility purposes, we need the original entity,
2726 -- which must be analyzed now because Load_Unit directly retrieves
2727 -- the renamed unit, and the renaming declaration itself has not
2728 -- been analyzed.
2735 -- Guard against missing or misspelled child units
2741 else
2744 -- Mark the node to indicate that a related error has been posted.
2745 -- This defends further compilation passes against improper use of
2746 -- the invalid WITH clause node.
2754 -- If the withed unit is System, and a system extension pragma is
2755 -- present, compile the extension now, rather than waiting for a
2756 -- visibility check on a specific entity.
2762 then
2763 -- If the extension is not present, an error will have been emitted
2768 -- Ada 2005 (AI-262): Remove from visibility the entity corresponding
2769 -- to private_with units; they will be made visible later (just before
2770 -- the private part is analyzed)
2777 ------------------------------
2778 -- Check_Private_Child_Unit --
2779 ------------------------------
2791 -- Returns true if and only if the library unit is declared with
2792 -- an explicit designation of private.
2794 -----------------------------
2795 -- Is_Private_Library_Unit --
2796 -----------------------------
2801 begin
2805 -- Start of processing for Check_Private_Child_Unit
2807 begin
2814 -- The parent is itself a body. The parent entity is to be found in
2815 -- the corresponding spec.
2820 -- If the parent itself is a subunit, Curr_Unit is the entity of the
2821 -- enclosing body, retrieve the spec entity which is the proper
2822 -- ancestor we need for the following tests.
2830 else
2838 else
2843 -- Loop through context items
2848 -- Ada 2005 (AI-262): Allow private_with of a private child package
2849 -- in public siblings
2855 then
2858 declare
2864 begin
2865 -- If the child unit is a public child then locate the nearest
2866 -- private ancestor. Child_Parent will then be set to the
2867 -- parent of that ancestor.
2872 loop
2884 loop
2885 Curr_Private :=
2898 then
2899 Error_Msg_NE
2903 else
2904 Error_Msg_N
2906 Error_Msg_NE
2911 elsif Curr_Private
2916 then
2919 else
2920 Error_Msg_NE
2932 ----------------------
2933 -- Check_Stub_Level --
2934 ----------------------
2940 begin
2942 N_Subprogram_Body,
2943 N_Task_Body,
2944 N_Protected_Body)
2946 then
2949 -- In an instance, a missing stub appears at any level. A warning
2950 -- message will have been emitted already for the missing file.
2960 ------------------------
2961 -- Expand_With_Clause --
2962 ------------------------
2971 -- Build name to be used in implicit with_clause. In most cases this
2972 -- is the source name, but if renamings are present we must make the
2973 -- original unit visible, not the one it renames. The entity in the
2974 -- with clause is the renamed unit, but the identifier is the one from
2975 -- the source, which allows us to recover the unit renaming.
2977 ---------------------
2978 -- Build_Unit_Name --
2979 ---------------------
2985 begin
2989 else
2994 and then
2996 = N_Package_Renaming_Declaration
2997 then
2998 -- The name in the with_clause is of the form A.B.C, and B is
2999 -- given by a renaming declaration. In that case we may not
3000 -- have analyzed the unit for B, but replaced it directly in
3001 -- lib-load with the unit it renames. We have to make A.B
3002 -- visible, so analyze the declaration for B now, in case it
3003 -- has not been done yet.
3006 Analyze
3007 (Parent
3011 Result :=
3021 -- Start of processing for Expand_With_Clause
3023 begin
3024 Withn :=
3034 -- If the unit is a package or generic package declaration, a private_
3035 -- with_clause on a child unit implies that the implicit with on the
3036 -- parent is also private.
3039 N_Generic_Package_Declaration)
3040 then
3053 -----------------------
3054 -- Get_Parent_Entity --
3055 -----------------------
3058 begin
3061 then
3062 return Defining_Entity
3066 else
3071 ---------------------
3072 -- Has_With_Clause --
3073 ---------------------
3075 function Has_With_Clause
3079 is
3083 -- Return the entity for the unit named in a [limited] with clause
3085 ----------------
3086 -- Named_Unit --
3087 ----------------
3090 begin
3093 else
3098 -- Start of processing for Has_With_Clause
3100 begin
3107 then
3118 -----------------------------
3119 -- Implicit_With_On_Parent --
3120 -----------------------------
3122 procedure Implicit_With_On_Parent
3125 is
3133 -- Build prefix of child unit name. Recurse if needed
3136 -- If the unit is a child unit, build qualified name with all ancestors
3138 -------------------------
3139 -- Build_Ancestor_Name --
3140 -------------------------
3147 begin
3148 -- Ancestor may have been rewritten as a package body. Retrieve
3149 -- the original spec to trace earlier ancestors.
3153 then
3159 else
3160 return
3167 ---------------------
3168 -- Build_Unit_Name --
3169 ---------------------
3174 begin
3178 else
3179 Result :=
3189 -- Start of processing for Implicit_With_On_Parent
3191 begin
3192 -- The unit of the current compilation may be a package body that
3193 -- replaces an instance node. In this case we need the original instance
3194 -- node to construct the proper parent name.
3198 then
3202 -- We add the implicit with if the child unit is the current unit being
3203 -- compiled. If the current unit is a body, we do not want to add an
3204 -- implicit_with a second time to the corresponding spec.
3208 then
3219 -- Node is placed at the beginning of the context items, so that
3220 -- subsequent use clauses on the parent can be validated.
3231 --------------
3232 -- In_Chain --
3233 --------------
3238 begin
3243 else
3251 ---------------------
3252 -- Install_Context --
3253 ---------------------
3258 begin
3268 -----------------------------
3269 -- Install_Context_Clauses --
3270 -----------------------------
3280 begin
3281 -- First skip configuration pragmas at the start of the context. They
3282 -- are not technically part of the context clause, but that's where the
3283 -- parser puts them. Note they were analyzed in Analyze_Context.
3289 loop
3293 -- Loop through the actual context clause items. We process everything
3294 -- except Limited_With clauses in this routine. Limited_With clauses
3295 -- are separately installed (see Install_Limited_Context_Clauses).
3299 -- Case of explicit WITH clause
3303 then
3306 -- Limited withed units will be installed later
3310 -- If Name (Item) is not an entity name, something is wrong, and
3311 -- this will be detected in due course, for now ignore the item
3331 -- If the unit is a subprogram instance, it appears nested within
3332 -- a package that carries the parent information.
3336 then
3343 else
3344 -- If not an expanded name, the child unit must be a
3345 -- renaming, nothing to do.
3353 then
3354 Implicit_With_On_Parent
3358 -- Check license conditions unless this is a dummy unit
3370 -- Signal error of bad license
3372 -------------------
3373 -- License_Error --
3374 -------------------
3377 begin
3378 Error_Msg_N
3383 -- Start of processing for License_Check
3385 begin
3386 -- Exclude license check if withed unit is an internal unit.
3387 -- This situation arises e.g. with the GPL version of GNAT.
3392 -- Otherwise check various cases
3393 else
3400 License_Error;
3405 License_Error;
3410 License_Error;
3420 -- Case of USE PACKAGE clause
3425 -- Case of USE TYPE clause
3430 -- case of PRAGMA
3442 -- The unit also has implicit with_clauses on its own parents
3451 -- If the unit is a body, the context of the specification must also
3452 -- be installed. That includes private with_clauses in that context.
3457 then
3460 -- Only install private with-clauses of a spec that comes from
3461 -- source, excluding specs created for a subprogram body that is
3462 -- a child unit.
3465 Install_Private_With_Clauses
3471 -- If the unit is the body of a public child unit, the private
3472 -- declarations of the parent must be made visible. If the child
3473 -- unit is private, the private declarations have been installed
3474 -- already in the call to Install_Parents for the spec. Installing
3475 -- private declarations must be done for all ancestors of public
3476 -- child units. In addition, sibling units mentioned in the
3477 -- context clause of the body are directly visible.
3479 declare
3484 begin
3492 then
3503 -- For a package body, children in context are immediately visible
3509 N_Generic_Subprogram_Declaration,
3510 N_Package_Declaration,
3511 N_Subprogram_Declaration)
3512 then
3515 Set_Is_Private_Descendant
3520 else
3521 Set_Is_Private_Descendant
3532 -------------------------------------
3533 -- Install_Limited_Context_Clauses --
3534 -------------------------------------
3540 -- Check that the unlimited view of a given compilation_unit is not
3541 -- already visible through "use + renamings".
3544 -- Check that if a limited_with clause of a given compilation_unit
3545 -- mentions a descendant of a private child of some library unit, then
3546 -- the given compilation_unit shall be the declaration of a private
3547 -- descendant of that library unit, or a public descendant of such. The
3548 -- code is analogous to that of Check_Private_Child_Unit but we cannot
3549 -- use entities on the limited with_clauses because their units have not
3550 -- been analyzed, so we have to climb the tree of ancestors looking for
3551 -- private keywords.
3553 procedure Expand_Limited_With_Clause
3557 -- If a child unit appears in a limited_with clause, there are implicit
3558 -- limited_with clauses on all parents that are not already visible
3559 -- through a regular with clause. This procedure creates the implicit
3560 -- limited with_clauses for the parents and loads the corresponding
3561 -- units. The shadow entities are created when the inserted clause is
3562 -- analyzed. Implements Ada 2005 (AI-50217).
3564 ---------------------
3565 -- Check_Renamings --
3566 ---------------------
3576 begin
3579 -- Protect the frontend against previous critical errors
3582 when N_Subprogram_Declaration |
3583 N_Package_Declaration |
3584 N_Generic_Subprogram_Declaration |
3585 N_Generic_Package_Declaration =>
3592 -- Check "use + renamings"
3600 -- Look only at use package clauses
3604 -- Traverse the list of packages
3614 then
3615 -- The unlimited view is visible through use clause and
3616 -- renamings. There is no need to generate the error
3617 -- message here because Is_Visible_Through_Renamings
3618 -- takes care of generating the precise error message.
3624 -- The use clause may refer to a local package.
3625 -- Check all the enclosing scopes.
3633 Error_Msg_N
3646 -- Recursive call to check all the ancestors
3653 ---------------------------------------
3654 -- Check_Private_Limited_Withed_Unit --
3655 ---------------------------------------
3662 begin
3663 -- Compilation unit of the parent of the withed library unit
3667 -- If the child unit is a public child, then locate its nearest
3668 -- private ancestor, if any, then Child_Parent will then be set to
3669 -- the parent of that ancestor.
3674 loop
3685 -- Traverse all the ancestors of the current compilation unit to
3686 -- check if it is a descendant of named library unit.
3693 loop
3699 Error_Msg_N
3701 Error_Msg_NE
3706 or else Curr_Private
3709 N_Subprogram_Body,
3710 N_Subunit)
3711 then
3712 -- Current unit is private, of descendant of a private unit
3716 else
3717 Error_Msg_NE
3723 --------------------------------
3724 -- Expand_Limited_With_Clause --
3725 --------------------------------
3727 procedure Expand_Limited_With_Clause
3731 is
3737 -- Returns true if the context already includes a with_clause for
3738 -- this unit. If the with_clause is non-limited, the unit is fully
3739 -- visible and an implicit limited_with should not be created. If
3740 -- there is already a limited_with clause for W, a second one is
3741 -- simply redundant.
3743 --------------------------
3744 -- Previous_Withed_Unit --
3745 --------------------------
3750 begin
3751 -- A limited with_clause cannot appear in the same context_clause
3752 -- as a nonlimited with_clause which mentions the same library.
3758 then
3768 -- Start of processing for Expand_Limited_With_Clause
3770 begin
3773 -- Create node for name of withed unit
3775 Withn :=
3780 Withn :=
3792 Unum :=
3793 Load_Unit
3799 -- Do not generate a limited_with_clause on the current unit. This
3800 -- path is taken when a unit has a limited_with clause on one of its
3801 -- child units.
3808 Set_Corresponding_Spec
3815 -- Add implicit limited_with_clauses for parents of child units
3816 -- mentioned in limited_with clauses.
3830 -- Start of processing for Install_Limited_Context_Clauses
3832 begin
3838 then
3840 Expand_Limited_With_Clause
3850 -- A unit may have a limited with on itself if it has a limited
3851 -- with_clause on one of its child units. In that case it is
3852 -- already being compiled and it makes no sense to install its
3853 -- limited view.
3855 -- If the item is a limited_private_with_clause, install it if the
3856 -- current unit is a body or if it is a private child. Otherwise
3857 -- the private clause is installed before analyzing the private
3858 -- part of the current unit.
3862 and then
3863 not Is_Ancestor_Unit
3865 then
3869 N_Subprogram_Body,
3870 N_Subunit)
3871 then
3880 -- Ada 2005 (AI-412): Examine visible declarations of a package spec,
3881 -- looking for incomplete subtype declarations of incomplete types
3882 -- visible through a limited with clause.
3887 then
3888 declare
3893 begin
3897 and then
3899 and then
3901 then
3907 -- Convert an incomplete subtype declaration into a
3908 -- corresponding non-limited view subtype declaration.
3909 -- This is usually the case when analyzing a body that
3910 -- has regular with clauses, when the spec has limited
3911 -- ones.
3913 -- If the non-limited view is still incomplete, it is
3914 -- the dummy entry already created, and the declaration
3915 -- cannot be reanalyzed. This is the case when installing
3916 -- a parent unit that has limited with-clauses.
3924 -- Reanalyze the declaration, suppressing the call to
3925 -- Enter_Name to avoid duplicate names.
3927 Analyze_Subtype_Declaration
3939 ---------------------
3940 -- Install_Parents --
3941 ---------------------
3949 begin
3959 N_Generic_Package_Declaration)
3961 then
3962 Error_Msg_N
3966 Error_Msg_N
3974 -- Verify that a child of an instance is itself an instance, or the
3975 -- renaming of one. Given that an instance that is a unit is replaced
3976 -- with a package declaration, check against the original node. The
3977 -- parent may be currently being instantiated, in which case it appears
3978 -- as a declaration, but the generic_parent is already established
3979 -- indicating that we deal with an instance.
3984 or else
3987 then
3989 else
3990 Error_Msg_N
3992 Lib_Unit);
3996 -- This is the recursive call that ensures all parents are loaded
4003 -- Now we can install the context for this parent
4009 -- The child unit is in the declarative region of the parent. The parent
4010 -- must therefore appear in the scope stack and be visible, as when
4011 -- compiling the corresponding body. If the child unit is private or it
4012 -- is a package body, private declarations must be accessible as well.
4013 -- Use declarations in the parent must also be installed. Finally, other
4014 -- child units of the same parent that are in the context are
4015 -- immediately visible.
4017 -- Find entity for compilation unit, and set its private descendant
4018 -- status as needed. Indicate that it is a compilation unit, which is
4019 -- redundant in general, but needed if this is a generated child spec
4020 -- for a child body without previous spec.
4034 -- Save current visibility of unit
4042 -- If the parent is a generic unit, its formal part may contain formal
4043 -- packages and use clauses for them.
4056 ----------------------------------
4057 -- Install_Private_With_Clauses --
4058 ----------------------------------
4064 begin
4068 Write_Eol;
4076 then
4077 -- If the unit is an ancestor of the current one, it is the
4078 -- case of a private limited with clause on a child unit, and
4079 -- the compilation of one of its descendants, In that case the
4080 -- limited view is errelevant.
4084 and then
4087 then
4090 else
4100 ----------------------
4101 -- Install_Siblings --
4102 ----------------------
4109 begin
4110 -- Iterate over explicit with clauses, and check whether the scope of
4111 -- each entity is an ancestor of the current unit, in which case it is
4112 -- immediately visible.
4117 -- Do not install private_with_clauses declaration, unless unit
4118 -- is itself a private child unit, or is a body. Note that for a
4119 -- subprogram body the private_with_clause does not take effect until
4120 -- after the specification.
4126 then
4132 then
4137 then
4140 -- Check for the presence of another unit in the context that
4141 -- may be inadvertently hidden by the child.
4148 then
4149 declare
4152 begin
4157 then
4158 Error_Msg_NE
4170 -- The With_Clause may be on a grand-child or one of its further
4171 -- descendants, which makes a child immediately visible. Examine
4172 -- ancestry to determine whether such a child exists. For example,
4173 -- if current unit is A.C, and with_clause is on A.X.Y.Z, then X
4174 -- is immediately visible.
4177 declare
4180 begin
4193 -- If the item is a private with-clause on a child unit, the parent
4194 -- may have been installed already, but the child unit must remain
4195 -- invisible until installed in a private part or body, unless there
4196 -- is already a regular with_clause for it in the current unit.
4202 declare
4206 -- Scan context of current unit, to check whether there is
4207 -- a with_clause on the same unit as a private with-clause
4208 -- on a parent, in which case child unit is visible. If the
4209 -- unit is a grand-child, the same applies to its parent.
4211 ----------------
4212 -- In_Context --
4213 ----------------
4216 begin
4217 Clause :=
4224 then
4226 or else
4229 then
4240 begin
4250 ---------------------------------
4251 -- Install_Limited_Withed_Unit --
4252 ---------------------------------
4263 -- A unit mentioned in a limited with_clause may not be mentioned in
4264 -- a regular with_clause, but must still be included in the current
4265 -- partition. We need to determine whether the unit needs a body, so
4266 -- that the binder can determine the name of the file to be compiled.
4267 -- Checking whether a unit needs a body can be done without semantic
4268 -- analysis, by examining the nature of the declarations in the package.
4270 function Has_Limited_With_Clause
4273 -- Determine whether any package in the ancestor chain starting with
4274 -- C_Unit has a limited with clause for package Pack.
4277 -- Check if some package installed though normal with-clauses has a
4278 -- renaming declaration of package P. AARM 10.1.2(21/2).
4280 -------------------------
4281 -- Check_Body_Required --
4282 -------------------------
4289 -- Recursive procedure that does the work and checks nested packages
4291 ------------------------
4292 -- Check_Declarations --
4293 ------------------------
4302 -- If a pragma import applies to a previous subprogram, the
4303 -- enclosing unit may not need a body. The processing is syntactic
4304 -- and does not require a declaration to be analyzed. The code
4305 -- below also handles pragma Import when applied to a subprogram
4306 -- that renames another. In this case the pragma applies to the
4307 -- renamed entity.
4308 --
4309 -- Chains of multiple renames are not handled by the code below.
4310 -- It is probably impossible to handle all cases without proper
4311 -- name resolution. In such cases the algorithm is conservative
4312 -- and will indicate that a body is needed???
4314 -------------------------
4315 -- Check_Pragma_Import --
4316 -------------------------
4325 -- Make one pass over list of subprograms. Called again if
4326 -- subprogram is a renaming. E is known to be an identifier.
4328 ---------------------
4329 -- Remove_Homonyms --
4330 ---------------------
4334 -- Name of renamed entity, if any
4336 begin
4341 /= N_Subprogram_Renaming_Declaration
4342 then
4346 else
4350 else
4362 -- Renaming of attribute
4364 else
4370 -- Start of processing for Check_Pragma_Import
4372 begin
4373 -- Find name of entity in Import pragma. We have not analyzed
4374 -- the construct, so we must guard against syntax errors.
4380 then
4382 else
4389 -- Start of processing for Check_Declarations
4391 begin
4392 -- Search for Elaborate Body pragma
4397 loop
4406 -- Look for declarations that require the presence of a body. We
4407 -- have already skipped pragmas at the start of the list.
4411 -- Subprogram that comes from source means body may be needed.
4412 -- Save for subsequent examination of import pragmas.
4416 N_Subprogram_Renaming_Declaration,
4417 N_Generic_Subprogram_Declaration))
4418 then
4421 -- Package declaration of generic package declaration. We need
4422 -- to recursively examine nested declarations.
4425 N_Generic_Package_Declaration)
4426 then
4431 then
4438 -- Same set of tests for private part. In addition to subprograms
4439 -- detect the presence of Taft Amendment types (incomplete types
4440 -- completed in the body).
4446 N_Subprogram_Renaming_Declaration,
4447 N_Generic_Subprogram_Declaration))
4448 then
4452 N_Generic_Package_Declaration)
4453 then
4456 -- Collect incomplete type declarations for separate pass
4463 then
4470 -- Now check incomplete declarations to locate Taft amendment
4471 -- types. This can be done by examining the defining identifiers
4472 -- of type declarations without real semantic analysis.
4474 declare
4477 begin
4485 then
4492 -- If no completion, this is a TAT, and a body is needed
4503 -- Finally, check whether there are subprograms that still require
4504 -- a body, i.e. are not renamings or null.
4507 declare
4511 begin
4517 = N_Subprogram_Renaming_Declaration
4518 then
4523 then
4526 else
4537 -- Start of processing for Check_Body_Required
4539 begin
4540 -- If this is an imported package (Java and CIL usage) no body is
4541 -- needed. Scan list of pragmas that may follow a compilation unit
4542 -- to look for a relevant pragma Import.
4545 declare
4548 begin
4553 then
4565 -----------------------------
4566 -- Has_Limited_With_Clause --
4567 -----------------------------
4569 function Has_Limited_With_Clause
4572 is
4576 begin
4583 -- Retrieve the Compilation_Unit node for Par and determine if
4584 -- its context clauses contain a limited with for Pack.
4596 -- If there are more ancestors, climb up the tree, otherwise we
4597 -- are done.
4601 else
4609 ----------------------------------
4610 -- Is_Visible_Through_Renamings --
4611 ----------------------------------
4620 begin
4621 -- Example of the error detected by this subprogram:
4623 -- package P is
4624 -- type T is ...
4625 -- end P;
4627 -- with P;
4628 -- package Q is
4629 -- package Ren_P renames P;
4630 -- end Q;
4632 -- with Q;
4633 -- package R is ...
4635 -- limited with P; -- ERROR
4636 -- package R.C is ...
4640 loop
4646 N_Package_Declaration
4647 then
4648 Decl :=
4649 First (Visible_Declarations
4654 then
4655 -- Generate the error message only if the current unit
4656 -- is a package declaration; in case of subprogram
4657 -- bodies and package bodies we just return True to
4658 -- indicate that the limited view must not be
4659 -- installed.
4662 Error_Msg_N
4666 Error_Msg_NE
4683 -- If it is a body not acting as spec, follow pointer to the
4684 -- corresponding spec, otherwise follow pointer to parent spec.
4689 then
4692 -- Aux_Unit is a body that acts as a spec. Clause has
4693 -- already been flagged as illegal.
4697 else
4701 else
4711 -- Start of processing for Install_Limited_Withed_Unit
4713 begin
4716 -- In case of limited with_clause on subprograms, generics, instances,
4717 -- or renamings, the corresponding error was previously posted and we
4718 -- have nothing to do here. If the file is missing altogether, it has
4719 -- no source location.
4723 then
4729 -- Handle child packages
4736 -- Do not install the limited-view if the context of the unit is already
4737 -- available through a regular with clause.
4741 then
4745 -- Do not install the limited-view if the full-view is already visible
4746 -- through renaming declarations.
4752 -- Do not install the limited view if this is the unit being analyzed.
4753 -- This unusual case will happen when a unit has a limited_with clause
4754 -- on one of its children. The compilation of the child forces the load
4755 -- of the parent which tries to install the limited view of the child
4756 -- again. Installing the limited view must also be disabled when
4757 -- compiling the body of the child unit.
4762 and then Is_Ancestor_Unit
4764 then
4768 -- This scenario is similar to the one above, the difference is that the
4769 -- compilation of sibling Par.Sib forces the load of parent Par which
4770 -- tries to install the limited view of Lim_Pack [1]. However Par.Sib
4771 -- has a with clause for Lim_Pack [2] in its body, and thus needs the
4772 -- non-limited views of all entities from Lim_Pack.
4774 -- limited with Lim_Pack; -- [1]
4775 -- package Par is ... package Lim_Pack is ...
4777 -- with Lim_Pack; -- [2]
4778 -- package Par.Sib is ... package body Par.Sib is ...
4780 -- In this case Main_Unit_Entity is the spec of Par.Sib and Current_
4781 -- Sem_Unit is the body of Par.Sib.
4787 -- The body has a regular with clause
4792 -- One of the ancestors has a limited with clause
4795 N_Package_Specification
4797 then
4801 -- A common use of the limited-with is to have a limited-with in the
4802 -- package spec, and a normal with in its package body. For example:
4804 -- limited with X; -- [1]
4805 -- package A is ...
4807 -- with X; -- [2]
4808 -- package body A is ...
4810 -- The compilation of A's body installs the context clauses found at [2]
4811 -- and then the context clauses of its specification (found at [1]). As
4812 -- a consequence, at [1] the specification of X has been analyzed and it
4813 -- is immediately visible. According to the semantics of limited-with
4814 -- context clauses we don't install the limited view because the full
4815 -- view of X supersedes its limited view.
4818 and then
4821 then
4823 -- The presence of both the limited and the analyzed nonlimited view
4824 -- may also be an error, such as an illegal context for a limited
4825 -- with_clause. In that case, do not process the context item at all.
4832 declare
4834 begin
4840 then
4848 -- If this is a child body, assume that the nonlimited with_clause
4849 -- appears in an ancestor. Could be refined ???
4851 if Is_Child_Unit
4852 (Defining_Entity
4854 then
4858 else
4860 -- If in package declaration, nonlimited view brought in from
4861 -- parent unit or some error condition.
4870 Write_Eol;
4873 -- If the unit has not been analyzed and the limited view has not been
4874 -- already installed then we install it.
4879 -- Minimum decoration
4891 -- Place entity on visibility structure
4899 Write_Eol;
4902 -- Install the incomplete view. The first element of the limited
4903 -- view is a header (an E_Package entity) used to reference the
4904 -- first shadow entity in the private part of the package.
4911 loop
4918 Write_Eol;
4925 -- If the unit appears in a previous regular with_clause, the regular
4926 -- entities of the public part of the withed package must be replaced
4927 -- by the shadow ones.
4929 -- This code must be kept synchronized with the code that replaces the
4930 -- shadow entities by the real entities (see body of Remove_Limited
4931 -- With_Clause); otherwise the contents of the homonym chains are not
4932 -- consistent.
4934 else
4935 -- Hide all the type entities of the public part of the package to
4936 -- avoid its usage. This is needed to cover all the subtype decla-
4937 -- rations because we do not remove them from the homonym chain.
4949 -- Replace the real entities by the shadow entities of the limited
4950 -- view. The first element of the limited view is a header that is
4951 -- used to reference the first shadow entity in the private part
4952 -- of the package. Successive elements are the limited views of the
4953 -- type (including regular incomplete types) declared in the package.
4960 loop
4963 -- Do not unchain nested packages and child units
4967 then
4968 declare
4971 begin
4975 -- Replace E in the homonyms list, so that the limited view
4976 -- becomes available.
4978 -- If the non-limited view is a record with an anonymous
4979 -- self-referential component, the analysis of the record
4980 -- declaration creates an incomplete type with the same name
4981 -- in order to define an internal access type. The visible
4982 -- entity is now the incomplete type, and that is the one to
4983 -- replace in the visibility structure.
4986 or else
4989 then
4993 else
4994 loop
4997 -- E may have been removed when installing a previous
4998 -- limited_with_clause.
5015 Write_Eol;
5023 -- The package must be visible while the limited-with clause is active
5024 -- because references to the type P.T must resolve in the usual way.
5025 -- In addition, we remember that the limited-view has been installed to
5026 -- uninstall it at the point of context removal.
5031 -- If unit has not been analyzed in some previous context, check
5032 -- (imperfectly ???) whether it might need a body.
5035 Check_Body_Required;
5038 -- If the package in the limited_with clause is a child unit, the clause
5039 -- is unanalyzed and appears as a selected component. Recast it as an
5040 -- expanded name so that the entity can be properly set. Use entity of
5041 -- parent, if available, for higher ancestors in the name.
5044 declare
5048 begin
5053 loop
5056 -- Set entity of parent identifiers if the unit is a child
5057 -- unit. This ensures that the tree is properly formed from
5058 -- semantic point of view (e.g. for ASIS queries). The unit
5059 -- entities are not fully analyzed, so we need to follow unit
5060 -- links in the tree.
5065 Ent :=
5066 Defining_Entity
5069 -- Set entity of last ancestor
5082 -------------------------
5083 -- Install_Withed_Unit --
5084 -------------------------
5086 procedure Install_Withed_Unit
5089 is
5093 begin
5094 -- Ada 2005 (AI-262): Do not install the private withed unit if we are
5095 -- compiling a package declaration and the Private_With_OK flag was not
5096 -- set by the caller. These declarations will be installed later (before
5097 -- analyzing the private part of the package).
5102 then
5109 else
5114 Write_Eol;
5117 -- We do not apply the restrictions to an internal unit unless we are
5118 -- compiling the internal unit as a main unit. This check is also
5119 -- skipped for dummy units (for missing packages).
5124 then
5125 Check_Restricted_Unit
5131 -- If the unit is not analyzed after analysis of the with clause and
5132 -- it is an instantiation then it awaits a body and is the main unit.
5133 -- Its appearance in the context of some other unit indicates a
5134 -- circular dependency (DEC suite perversity).
5138 then
5139 Error_Msg_N
5144 -- Abandon processing in case of previous errors
5147 Check_Error_Detected;
5153 -- If the child unit appears in the context of its parent, it is
5154 -- immediately visible.
5162 then
5163 -- Set flag as well on the visible entity that denotes the
5164 -- instance, which renames the current one.
5166 Set_Is_Visible_Lib_Unit
5167 (Related_Instance
5171 -- The parent unit may have been installed already, and may have
5172 -- appeared in a use clause.
5191 -- A with-clause overrides a with-type clause: there are no restric-
5192 -- tions on the use of package entities.
5198 -- Ada 2005 (AI-377): it is illegal for a with_clause to name a child
5199 -- unit if there is a visible homograph for it declared in the same
5200 -- declarative region. This pathological case can only arise when an
5201 -- instance I1 of a generic unit G1 has an explicit child unit I1.G2,
5202 -- G1 has a generic child also named G2, and the context includes with_
5203 -- clauses for both I1.G2 and for G1.G2, making an implicit declaration
5204 -- of I1.G2 visible as well. If the child unit is named Standard, do
5205 -- not apply the check to the Standard package itself.
5210 then
5211 declare
5217 begin
5227 then
5229 Error_Msg_N
5232 With_Clause);
5238 then
5239 -- With_clause for child unit of instance appears before
5240 -- in the context. We want to place the error message on
5241 -- it, not on the generic child unit itself.
5243 declare
5246 begin
5254 Error_Msg_N
5257 Prev_Clause);
5269 -------------------
5270 -- Is_Child_Spec --
5271 -------------------
5276 begin
5287 ------------------------------------
5288 -- Is_Legal_Shadow_Entity_In_Body --
5289 ------------------------------------
5293 begin
5295 and then
5296 Has_With_Clause
5300 ----------------------
5301 -- Is_Ancestor_Unit --
5302 ----------------------
5307 begin
5311 else
5316 -----------------------
5317 -- Load_Needed_Body --
5318 -----------------------
5320 -- N is a generic unit named in a with clause, or else it is a unit that
5321 -- contains a generic unit or an inlined function. In order to perform an
5322 -- instantiation, the body of the unit must be present. If the unit itself
5323 -- is generic, we assume that an instantiation follows, and load & analyze
5324 -- the body unconditionally. This forces analysis of the spec as well.
5326 -- If the unit is not generic, but contains a generic unit, it is loaded on
5327 -- demand, at the point of instantiation (see ch12).
5329 procedure Load_Needed_Body
5333 is
5338 -- The loading and analysis is done with style checks off
5340 begin
5346 Unum :=
5347 Load_Unit
5357 else
5363 Write_Eol;
5377 -------------------------
5378 -- Build_Limited_Views --
5379 -------------------------
5387 -- The corresponding shadow entity of the withed package. This entity
5388 -- offers incomplete views of all types and visible packages declared
5389 -- within.
5392 -- The last shadow entity created by routine Build_Shadow_Entity
5394 function Build_Shadow_Entity
5398 -- Create a shadow entity that hides Ent and offers an incomplete view
5399 -- of Ent. Scop is the proper scope. Flag Is_Tagged should be set when
5400 -- Ent is a tagged type. The generated entity is added to Lim_Header.
5401 -- This routine updates the value of Last_Shadow.
5404 -- Perform minimal decoration of a package or its corresponding shadow
5405 -- entity denoted by Ent. Scop is the proper scope.
5407 procedure Decorate_Type
5412 -- Perform minimal decoration of a type or its corresponding shadow
5413 -- entity denoted by Ent. Scop is the proper scope. Flag Is_Tagged
5414 -- should be set when Ent is a tagged type. Flag Materialize should be
5415 -- set when Ent is a tagged type and its class-wide type needs to appear
5416 -- in the tree.
5419 -- Inspect declarative list Decls and create shadow entities for all
5420 -- types and packages encountered. Scop is the proper scope.
5422 -------------------------
5423 -- Build_Shadow_Entity --
5424 -------------------------
5426 function Build_Shadow_Entity
5430 is
5433 begin
5434 -- The shadow entity must share the same name and parent as the
5435 -- entity it hides.
5443 -- Add the new shadow entity to the limited view of the package
5464 ----------------------
5465 -- Decorate_Package --
5466 ----------------------
5469 begin
5475 -------------------
5476 -- Decorate_Type --
5477 -------------------
5479 procedure Decorate_Type
5484 is
5487 begin
5488 -- An unanalyzed type or a shadow entity of a type is treated as an
5489 -- incomplete type.
5499 -- A tagged type and its corresponding shadow entity share one common
5500 -- class-wide type.
5506 CW_Typ :=
5507 New_External_Entity
5512 -- Set parent to be the same as the parent of the tagged type.
5513 -- We need a parent field set, and it is supposed to point to
5514 -- the declaration of the type. The tagged type declaration
5515 -- essentially declares two separate types, the tagged type
5516 -- itself and the corresponding class-wide type, so it is
5517 -- reasonable for the parent fields to point to the declaration
5518 -- in both cases.
5537 --------------------------
5538 -- Process_Declarations --
5539 --------------------------
5550 begin
5551 -- Inspect the declarative list, looking for type declarations and
5552 -- nested packages.
5557 -- Types
5560 N_Incomplete_Type_Declaration,
5561 N_Private_Extension_Declaration,
5562 N_Private_Type_Declaration,
5563 N_Protected_Type_Declaration,
5564 N_Task_Type_Declaration)
5565 then
5568 -- Determine whether the type is tagged. Note that packages
5569 -- included via a limited with clause are not always analyzed,
5570 -- hence the tree lookup rather than the use of attribute
5571 -- Is_Tagged_Type.
5576 Is_Tagged :=
5579 or else
5584 N_Private_Type_Declaration)
5585 then
5591 else
5595 -- Perform minor decoration when the withed package has not
5596 -- been analyzed.
5602 -- Create a shadow entity that hides the type and offers an
5603 -- incomplete view of the said type.
5607 -- Packages
5612 -- Perform minor decoration when the withed package has not
5613 -- been analyzed.
5619 -- Create a shadow entity that offers a limited view of all
5620 -- visible types declared within.
5624 Process_Declarations
5633 -- Local variables
5639 -- Start of processing for Build_Limited_Views
5641 begin
5644 -- A library_item mentioned in a limited_with_clause is a package
5645 -- declaration, not a subprogram declaration, generic declaration,
5646 -- generic instantiation, or package renaming declaration.
5656 when N_Generic_Package_Declaration |
5657 N_Generic_Subprogram_Declaration =>
5662 Error_Msg_N
5664 N);
5668 Error_Msg_N
5673 Error_Msg_N
5678 Error_Msg_N
5686 -- The withed unit may not be analyzed, but the with calause itself
5687 -- must be minimally decorated. This ensures that the checks on unused
5688 -- with clauses also process limieted withs.
5700 -- Check if the chain is already built
5708 -- Create the shadow package wich hides the withed unit and provides
5709 -- incomplete view of all types and packages declared within.
5716 -- Inspect the visible declarations of the withed unit and create shadow
5717 -- entities that hide existing types and packages.
5719 Process_Declarations
5725 -- Ada 2005 (AI-262): Build the limited view of the private declarations
5726 -- to accomodate limited private with clauses.
5728 Process_Declarations
5734 else
5742 -------------------------------
5743 -- Check_Body_Needed_For_SAL --
5744 -------------------------------
5749 -- Determine whether use of entity E might require the presence of its
5750 -- body. For a package this requires a recursive traversal of all nested
5751 -- declarations.
5753 ---------------------------
5754 -- Entity_Needed_For_SAL --
5755 ---------------------------
5760 begin
5768 and then
5771 then
5777 then
5789 else
5794 -- Start of processing for Check_Body_Needed_For_SAL
5796 begin
5799 N_Generic_Package_Declaration
5800 and then
5802 then
5810 N_Subprogram_Declaration
5812 then
5816 Check_Body_Needed_For_SAL
5821 then
5826 then
5827 Check_Body_Needed_For_SAL
5832 --------------------
5833 -- Remove_Context --
5834 --------------------
5839 begin
5840 -- If this is a child unit, first remove the parent units
5849 ----------------------------
5850 -- Remove_Context_Clauses --
5851 ----------------------------
5857 begin
5858 -- Ada 2005 (AI-50217): We remove the context clauses in two phases:
5859 -- limited-views first and regular-views later (to maintain the
5860 -- stack model).
5862 -- First Phase: Remove limited_with context clauses
5867 -- We are interested only in with clauses which got installed
5868 -- on entry.
5873 then
5880 -- Second Phase: Loop through context items and undo regular
5881 -- with_clauses and use_clauses.
5886 -- We are interested only in with clauses which got installed on
5887 -- entry, as indicated by their Context_Installed flag set
5892 then
5897 then
5898 -- Remove items from one with'ed unit
5915 --------------------------------
5916 -- Remove_Limited_With_Clause --
5917 --------------------------------
5927 begin
5930 -- In case of limited with_clause on subprograms, generics, instances,
5931 -- or renamings, the corresponding error was previously posted and we
5932 -- have nothing to do here.
5940 -- Handle child packages
5950 Write_Eol;
5953 -- Prepare the removal of the shadow entities from visibility. The first
5954 -- element of the limited view is a header (an E_Package entity) that is
5955 -- used to reference the first shadow entity in the private part of the
5956 -- package
5961 -- Remove package and shadow entities from visibility if it has not
5962 -- been analyzed
5973 -- Otherwise this package has already appeared in the closure and its
5974 -- shadow entities must be replaced by its real entities. This code
5975 -- must be kept synchronized with the complementary code in Install
5976 -- Limited_Withed_Unit.
5978 else
5979 -- Real entities that are type or subtype declarations were hidden
5980 -- from visibility at the point of installation of the limited-view.
5981 -- Now we recover the previous value of the hidden attribute.
5994 loop
5995 -- Nested packages and child units were not unchained
5999 then
6000 -- If the package has incomplete types, the limited view of the
6001 -- incomplete type is in fact never visible (AI05-129) but we
6002 -- have created a shadow entity E1 for it, that points to E2,
6003 -- a non-limited incomplete type. This in turn has a full view
6004 -- E3 that is the full declaration. There is a corresponding
6005 -- shadow entity E4. When reinstalling the non-limited view,
6006 -- E2 must become the current entity and E3 must be ignored.
6013 then
6015 -- Lim_Typ is the limited view of a full type declaration
6016 -- that has a previous incomplete declaration, i.e. E3 from
6017 -- the previous description. Nothing to insert.
6021 else
6029 else
6032 loop
6041 -- Preserve structure of homonym chain
6051 -- Indicate that the limited view of the package is not installed
6057 --------------------
6058 -- Remove_Parents --
6059 --------------------
6069 begin
6075 then
6086 -- Remove from visibility the siblings as well, which are directly
6087 -- visible while the parent is in scope.
6100 -- This is the recursive call to remove the context of any higher
6101 -- level parent. This recursion ensures that all parents are removed
6102 -- in the reverse order of their installation.
6108 ---------------------------------
6109 -- Remove_Private_With_Clauses --
6110 ---------------------------------
6116 -- Check whether a given unit appears in a regular with_clause. Used to
6117 -- determine whether a private_with_clause, implicit or explicit, should
6118 -- be ignored.
6120 ----------------------------
6121 -- In_Regular_With_Clause --
6122 ----------------------------
6125 is
6128 begin
6134 then
6143 -- Start of processing for Remove_Private_With_Clauses
6145 begin
6150 -- If private_with_clause is redundant, remove it from context,
6151 -- as a small optimization to subsequent handling of private_with
6152 -- clauses in other nested packages.
6155 declare
6157 begin
6169 else
6175 else
6181 ---------------------------------
6182 -- Remove_Unit_From_Visibility --
6183 ---------------------------------
6186 begin
6191 Write_Eol;
6198 -- If the unit is a wrapper package, the subprogram instance is
6199 -- what must be removed from visibility.
6206 --------
6207 -- sm --
6208 --------
6211 begin
6215 -------------
6216 -- Unchain --
6217 -------------
6222 begin
6231 else
6244 Write_Eol;