URL
https://opencores.org/ocsvn/openrisc/openrisc/trunk
Subversion Repositories openrisc
[/] [openrisc/] [tags/] [gnu-dev/] [fsf-gcc-snapshot-1-mar-12/] [or1k-gcc/] [gcc/] [ada/] [sem_ch10.adb] - Rev 847
Go to most recent revision | Compare with Previous | Blame | View Log
------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S E M _ C H 1 0 -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2012, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Atree; use Atree; with Debug; use Debug; with Einfo; use Einfo; with Errout; use Errout; with Exp_Util; use Exp_Util; with Elists; use Elists; with Fname; use Fname; with Fname.UF; use Fname.UF; with Freeze; use Freeze; with Impunit; use Impunit; with Inline; use Inline; with Lib; use Lib; with Lib.Load; use Lib.Load; with Lib.Xref; use Lib.Xref; with Namet; use Namet; with Nlists; use Nlists; with Nmake; use Nmake; with Opt; use Opt; with Output; use Output; with Par_SCO; use Par_SCO; with Restrict; use Restrict; with Rident; use Rident; with Rtsfind; use Rtsfind; with Sem; use Sem; with Sem_Aux; use Sem_Aux; with Sem_Ch3; use Sem_Ch3; with Sem_Ch6; use Sem_Ch6; with Sem_Ch7; use Sem_Ch7; with Sem_Ch8; use Sem_Ch8; with Sem_Dist; use Sem_Dist; with Sem_Prag; use Sem_Prag; with Sem_Util; use Sem_Util; with Sem_Warn; use Sem_Warn; with Stand; use Stand; with Sinfo; use Sinfo; with Sinfo.CN; use Sinfo.CN; with Sinput; use Sinput; with Snames; use Snames; with Style; use Style; with Stylesw; use Stylesw; with Tbuild; use Tbuild; with Uname; use Uname; package body Sem_Ch10 is ----------------------- -- Local Subprograms -- ----------------------- procedure Analyze_Context (N : Node_Id); -- Analyzes items in the context clause of compilation unit procedure Build_Limited_Views (N : Node_Id); -- Build and decorate the list of shadow entities for a package mentioned -- in a limited_with clause. If the package was not previously analyzed -- then it also performs a basic decoration of the real entities. This is -- required to do not pass non-decorated entities to the back-end. -- Implements Ada 2005 (AI-50217). procedure Check_Body_Needed_For_SAL (Unit_Name : Entity_Id); -- Check whether the source for the body of a compilation unit must be -- included in a standalone library. procedure Check_Private_Child_Unit (N : Node_Id); -- If a with_clause mentions a private child unit, the compilation unit -- must be a member of the same family, as described in 10.1.2. procedure Check_Stub_Level (N : Node_Id); -- Verify that a stub is declared immediately within a compilation unit, -- and not in an inner frame. procedure Expand_With_Clause (Item : Node_Id; Nam : Node_Id; N : Node_Id); -- When a child unit appears in a context clause, the implicit withs on -- parents are made explicit, and with clauses are inserted in the context -- clause before the one for the child. If a parent in the with_clause -- is a renaming, the implicit with_clause is on the renaming whose name -- is mentioned in the with_clause, and not on the package it renames. -- N is the compilation unit whose list of context items receives the -- implicit with_clauses. function Get_Parent_Entity (Unit : Node_Id) return Entity_Id; -- Get defining entity of parent unit of a child unit. In most cases this -- is the defining entity of the unit, but for a child instance whose -- parent needs a body for inlining, the instantiation node of the parent -- has not yet been rewritten as a package declaration, and the entity has -- to be retrieved from the Instance_Spec of the unit. function Has_With_Clause (C_Unit : Node_Id; Pack : Entity_Id; Is_Limited : Boolean := False) return Boolean; -- Determine whether compilation unit C_Unit contains a [limited] with -- clause for package Pack. Use the flag Is_Limited to designate desired -- clause kind. procedure Implicit_With_On_Parent (Child_Unit : Node_Id; N : Node_Id); -- If the main unit is a child unit, implicit withs are also added for -- all its ancestors. function In_Chain (E : Entity_Id) return Boolean; -- Check that the shadow entity is not already in the homonym chain, for -- example through a limited_with clause in a parent unit. procedure Install_Context_Clauses (N : Node_Id); -- Subsidiary to Install_Context and Install_Parents. Process all with -- and use clauses for current unit and its library unit if any. procedure Install_Limited_Context_Clauses (N : Node_Id); -- Subsidiary to Install_Context. Process only limited with_clauses for -- current unit. Implements Ada 2005 (AI-50217). procedure Install_Limited_Withed_Unit (N : Node_Id); -- Place shadow entities for a limited_with package in the visibility -- structures for the current compilation. Implements Ada 2005 (AI-50217). procedure Install_Withed_Unit (With_Clause : Node_Id; Private_With_OK : Boolean := False); -- If the unit is not a child unit, make unit immediately visible. The -- caller ensures that the unit is not already currently installed. The -- flag Private_With_OK is set true in Install_Private_With_Clauses, which -- is called when compiling the private part of a package, or installing -- the private declarations of a parent unit. procedure Install_Parents (Lib_Unit : Node_Id; Is_Private : Boolean); -- This procedure establishes the context for the compilation of a child -- unit. If Lib_Unit is a child library spec then the context of the parent -- is installed, and the parent itself made immediately visible, so that -- the child unit is processed in the declarative region of the parent. -- Install_Parents makes a recursive call to itself to ensure that all -- parents are loaded in the nested case. If Lib_Unit is a library body, -- the only effect of Install_Parents is to install the private decls of -- the parents, because the visible parent declarations will have been -- installed as part of the context of the corresponding spec. procedure Install_Siblings (U_Name : Entity_Id; N : Node_Id); -- In the compilation of a child unit, a child of any of the ancestor -- units is directly visible if it is visible, because the parent is in -- an enclosing scope. Iterate over context to find child units of U_Name -- or of some ancestor of it. function Is_Child_Spec (Lib_Unit : Node_Id) return Boolean; -- Lib_Unit is a library unit which may be a spec or a body. Is_Child_Spec -- returns True if Lib_Unit is a library spec which is a child spec, i.e. -- a library spec that has a parent. If the call to Is_Child_Spec returns -- True, then Parent_Spec (Lib_Unit) is non-Empty and points to the -- compilation unit for the parent spec. -- -- Lib_Unit can also be a subprogram body that acts as its own spec. If the -- Parent_Spec is non-empty, this is also a child unit. procedure Remove_Context_Clauses (N : Node_Id); -- Subsidiary of previous one. Remove use_ and with_clauses procedure Remove_Limited_With_Clause (N : Node_Id); -- Remove from visibility the shadow entities introduced for a package -- mentioned in a limited_with clause. Implements Ada 2005 (AI-50217). procedure Remove_Parents (Lib_Unit : Node_Id); -- Remove_Parents checks if Lib_Unit is a child spec. If so then the parent -- contexts established by the corresponding call to Install_Parents are -- removed. Remove_Parents contains a recursive call to itself to ensure -- that all parents are removed in the nested case. procedure Remove_Unit_From_Visibility (Unit_Name : Entity_Id); -- Reset all visibility flags on unit after compiling it, either as a main -- unit or as a unit in the context. procedure Unchain (E : Entity_Id); -- Remove single entity from visibility list procedure Analyze_Proper_Body (N : Node_Id; Nam : Entity_Id); -- Common processing for all stubs (subprograms, tasks, packages, and -- protected cases). N is the stub to be analyzed. Once the subunit name -- is established, load and analyze. Nam is the non-overloadable entity -- for which the proper body provides a completion. Subprogram stubs are -- handled differently because they can be declarations. procedure sm; -- A dummy procedure, for debugging use, called just before analyzing the -- main unit (after dealing with any context clauses). -------------------------- -- Limited_With_Clauses -- -------------------------- -- Limited_With clauses are the mechanism chosen for Ada 2005 to support -- mutually recursive types declared in different units. A limited_with -- clause that names package P in the context of unit U makes the types -- declared in the visible part of P available within U, but with the -- restriction that these types can only be used as incomplete types. -- The limited_with clause does not impose a semantic dependence on P, -- and it is possible for two packages to have limited_with_clauses on -- each other without creating an elaboration circularity. -- To support this feature, the analysis of a limited_with clause must -- create an abbreviated view of the package, without performing any -- semantic analysis on it. This "package abstract" contains shadow types -- that are in one-one correspondence with the real types in the package, -- and that have the properties of incomplete types. -- The implementation creates two element lists: one to chain the shadow -- entities, and one to chain the corresponding type entities in the tree -- of the package. Links between corresponding entities in both chains -- allow the compiler to select the proper view of a given type, depending -- on the context. Note that in contrast with the handling of private -- types, the limited view and the non-limited view of a type are treated -- as separate entities, and no entity exchange needs to take place, which -- makes the implementation must simpler than could be feared. ------------------------------ -- Analyze_Compilation_Unit -- ------------------------------ procedure Analyze_Compilation_Unit (N : Node_Id) is Unit_Node : constant Node_Id := Unit (N); Lib_Unit : Node_Id := Library_Unit (N); Spec_Id : Entity_Id; Main_Cunit : constant Node_Id := Cunit (Main_Unit); Par_Spec_Name : Unit_Name_Type; Unum : Unit_Number_Type; procedure Check_Redundant_Withs (Context_Items : List_Id; Spec_Context_Items : List_Id := No_List); -- Determine whether the context list of a compilation unit contains -- redundant with clauses. When checking body clauses against spec -- clauses, set Context_Items to the context list of the body and -- Spec_Context_Items to that of the spec. Parent packages are not -- examined for documentation purposes. procedure Generate_Parent_References (N : Node_Id; P_Id : Entity_Id); -- Generate cross-reference information for the parents of child units. -- N is a defining_program_unit_name, and P_Id is the immediate parent. --------------------------- -- Check_Redundant_Withs -- --------------------------- procedure Check_Redundant_Withs (Context_Items : List_Id; Spec_Context_Items : List_Id := No_List) is Clause : Node_Id; procedure Process_Body_Clauses (Context_List : List_Id; Clause : Node_Id; Used : in out Boolean; Used_Type_Or_Elab : in out Boolean); -- Examine the context clauses of a package body, trying to match the -- name entity of Clause with any list element. If the match occurs -- on a use package clause set Used to True, for a use type clause or -- pragma Elaborate[_All], set Used_Type_Or_Elab to True. procedure Process_Spec_Clauses (Context_List : List_Id; Clause : Node_Id; Used : in out Boolean; Withed : in out Boolean; Exit_On_Self : Boolean := False); -- Examine the context clauses of a package spec, trying to match -- the name entity of Clause with any list element. If the match -- occurs on a use package clause, set Used to True, for a with -- package clause other than Clause, set Withed to True. Limited -- with clauses, implicitly generated with clauses and withs -- having pragmas Elaborate or Elaborate_All applied to them are -- skipped. Exit_On_Self is used to control the search loop and -- force an exit whenever Clause sees itself in the search. -------------------------- -- Process_Body_Clauses -- -------------------------- procedure Process_Body_Clauses (Context_List : List_Id; Clause : Node_Id; Used : in out Boolean; Used_Type_Or_Elab : in out Boolean) is Nam_Ent : constant Entity_Id := Entity (Name (Clause)); Cont_Item : Node_Id; Prag_Unit : Node_Id; Subt_Mark : Node_Id; Use_Item : Node_Id; function Same_Unit (N : Node_Id; P : Entity_Id) return Boolean; -- In an expanded name in a use clause, if the prefix is a renamed -- package, the entity is set to the original package as a result, -- when checking whether the package appears in a previous with -- clause, the renaming has to be taken into account, to prevent -- spurious/incorrect warnings. A common case is use of Text_IO. --------------- -- Same_Unit -- --------------- function Same_Unit (N : Node_Id; P : Entity_Id) return Boolean is begin return Entity (N) = P or else (Present (Renamed_Object (P)) and then Entity (N) = Renamed_Object (P)); end Same_Unit; -- Start of processing for Process_Body_Clauses begin Used := False; Used_Type_Or_Elab := False; Cont_Item := First (Context_List); while Present (Cont_Item) loop -- Package use clause if Nkind (Cont_Item) = N_Use_Package_Clause and then not Used then -- Search through use clauses Use_Item := First (Names (Cont_Item)); while Present (Use_Item) and then not Used loop -- Case of a direct use of the one we are looking for if Entity (Use_Item) = Nam_Ent then Used := True; -- Handle nested case, as in "with P; use P.Q.R" else declare UE : Node_Id; begin -- Loop through prefixes looking for match UE := Use_Item; while Nkind (UE) = N_Expanded_Name loop if Same_Unit (Prefix (UE), Nam_Ent) then Used := True; exit; end if; UE := Prefix (UE); end loop; end; end if; Next (Use_Item); end loop; -- USE TYPE clause elsif Nkind (Cont_Item) = N_Use_Type_Clause and then not Used_Type_Or_Elab then Subt_Mark := First (Subtype_Marks (Cont_Item)); while Present (Subt_Mark) and then not Used_Type_Or_Elab loop if Same_Unit (Prefix (Subt_Mark), Nam_Ent) then Used_Type_Or_Elab := True; end if; Next (Subt_Mark); end loop; -- Pragma Elaborate or Elaborate_All elsif Nkind (Cont_Item) = N_Pragma and then (Pragma_Name (Cont_Item) = Name_Elaborate or else Pragma_Name (Cont_Item) = Name_Elaborate_All) and then not Used_Type_Or_Elab then Prag_Unit := First (Pragma_Argument_Associations (Cont_Item)); while Present (Prag_Unit) and then not Used_Type_Or_Elab loop if Entity (Expression (Prag_Unit)) = Nam_Ent then Used_Type_Or_Elab := True; end if; Next (Prag_Unit); end loop; end if; Next (Cont_Item); end loop; end Process_Body_Clauses; -------------------------- -- Process_Spec_Clauses -- -------------------------- procedure Process_Spec_Clauses (Context_List : List_Id; Clause : Node_Id; Used : in out Boolean; Withed : in out Boolean; Exit_On_Self : Boolean := False) is Nam_Ent : constant Entity_Id := Entity (Name (Clause)); Cont_Item : Node_Id; Use_Item : Node_Id; begin Used := False; Withed := False; Cont_Item := First (Context_List); while Present (Cont_Item) loop -- Stop the search since the context items after Cont_Item have -- already been examined in a previous iteration of the reverse -- loop in Check_Redundant_Withs. if Exit_On_Self and Cont_Item = Clause then exit; end if; -- Package use clause if Nkind (Cont_Item) = N_Use_Package_Clause and then not Used then Use_Item := First (Names (Cont_Item)); while Present (Use_Item) and then not Used loop if Entity (Use_Item) = Nam_Ent then Used := True; end if; Next (Use_Item); end loop; -- Package with clause. Avoid processing self, implicitly -- generated with clauses or limited with clauses. Note that -- we examine with clauses having pragmas Elaborate or -- Elaborate_All applied to them due to cases such as: -- with Pack; -- with Pack; -- pragma Elaborate (Pack); -- -- In this case, the second with clause is redundant since -- the pragma applies only to the first "with Pack;". elsif Nkind (Cont_Item) = N_With_Clause and then not Implicit_With (Cont_Item) and then not Limited_Present (Cont_Item) and then Cont_Item /= Clause and then Entity (Name (Cont_Item)) = Nam_Ent then Withed := True; end if; Next (Cont_Item); end loop; end Process_Spec_Clauses; -- Start of processing for Check_Redundant_Withs begin Clause := Last (Context_Items); while Present (Clause) loop -- Avoid checking implicitly generated with clauses, limited with -- clauses or withs that have pragma Elaborate or Elaborate_All. if Nkind (Clause) = N_With_Clause and then not Implicit_With (Clause) and then not Limited_Present (Clause) and then not Elaborate_Present (Clause) then -- Package body-to-spec check if Present (Spec_Context_Items) then declare Used_In_Body : Boolean := False; Used_In_Spec : Boolean := False; Used_Type_Or_Elab : Boolean := False; Withed_In_Spec : Boolean := False; begin Process_Spec_Clauses (Context_List => Spec_Context_Items, Clause => Clause, Used => Used_In_Spec, Withed => Withed_In_Spec); Process_Body_Clauses (Context_List => Context_Items, Clause => Clause, Used => Used_In_Body, Used_Type_Or_Elab => Used_Type_Or_Elab); -- "Type Elab" refers to the presence of either a use -- type clause, pragmas Elaborate or Elaborate_All. -- +---------------+---------------------------+------+ -- | Spec | Body | Warn | -- +--------+------+--------+------+-----------+------+ -- | Withed | Used | Withed | Used | Type Elab | | -- | X | | X | | | X | -- | X | | X | X | | | -- | X | | X | | X | | -- | X | | X | X | X | | -- | X | X | X | | | X | -- | X | X | X | | X | | -- | X | X | X | X | | X | -- | X | X | X | X | X | | -- +--------+------+--------+------+-----------+------+ if (Withed_In_Spec and then not Used_Type_Or_Elab) and then ((not Used_In_Spec and then not Used_In_Body) or else Used_In_Spec) then Error_Msg_N -- CODEFIX ("?redundant with clause in body", Clause); end if; Used_In_Body := False; Used_In_Spec := False; Used_Type_Or_Elab := False; Withed_In_Spec := False; end; -- Standalone package spec or body check else declare Dont_Care : Boolean := False; Withed : Boolean := False; begin -- The mechanism for examining the context clauses of a -- package spec can be applied to package body clauses. Process_Spec_Clauses (Context_List => Context_Items, Clause => Clause, Used => Dont_Care, Withed => Withed, Exit_On_Self => True); if Withed then Error_Msg_N -- CODEFIX ("?redundant with clause", Clause); end if; end; end if; end if; Prev (Clause); end loop; end Check_Redundant_Withs; -------------------------------- -- Generate_Parent_References -- -------------------------------- procedure Generate_Parent_References (N : Node_Id; P_Id : Entity_Id) is Pref : Node_Id; P_Name : Entity_Id := P_Id; begin Pref := Name (Parent (Defining_Entity (N))); if Nkind (Pref) = N_Expanded_Name then -- Done already, if the unit has been compiled indirectly as -- part of the closure of its context because of inlining. return; end if; while Nkind (Pref) = N_Selected_Component loop Change_Selected_Component_To_Expanded_Name (Pref); Set_Entity (Pref, P_Name); Set_Etype (Pref, Etype (P_Name)); Generate_Reference (P_Name, Pref, 'r'); Pref := Prefix (Pref); P_Name := Scope (P_Name); end loop; -- The guard here on P_Name is to handle the error condition where -- the parent unit is missing because the file was not found. if Present (P_Name) then Set_Entity (Pref, P_Name); Set_Etype (Pref, Etype (P_Name)); Generate_Reference (P_Name, Pref, 'r'); Style.Check_Identifier (Pref, P_Name); end if; end Generate_Parent_References; -- Start of processing for Analyze_Compilation_Unit begin Process_Compilation_Unit_Pragmas (N); -- If the unit is a subunit whose parent has not been analyzed (which -- indicates that the main unit is a subunit, either the current one or -- one of its descendents) then the subunit is compiled as part of the -- analysis of the parent, which we proceed to do. Basically this gets -- handled from the top down and we don't want to do anything at this -- level (i.e. this subunit will be handled on the way down from the -- parent), so at this level we immediately return. If the subunit ends -- up not analyzed, it means that the parent did not contain a stub for -- it, or that there errors were detected in some ancestor. if Nkind (Unit_Node) = N_Subunit and then not Analyzed (Lib_Unit) then Semantics (Lib_Unit); if not Analyzed (Proper_Body (Unit_Node)) then if Serious_Errors_Detected > 0 then Error_Msg_N ("subunit not analyzed (errors in parent unit)", N); else Error_Msg_N ("missing stub for subunit", N); end if; end if; return; end if; -- Analyze context (this will call Sem recursively for with'ed units) To -- detect circularities among with-clauses that are not caught during -- loading, we set the Context_Pending flag on the current unit. If the -- flag is already set there is a potential circularity. We exclude -- predefined units from this check because they are known to be safe. -- We also exclude package bodies that are present because circularities -- between bodies are harmless (and necessary). if Context_Pending (N) then declare Circularity : Boolean := True; begin if Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (Unit (N)))) then Circularity := False; else for U in Main_Unit + 1 .. Last_Unit loop if Nkind (Unit (Cunit (U))) = N_Package_Body and then not Analyzed (Cunit (U)) then Circularity := False; exit; end if; end loop; end if; if Circularity then Error_Msg_N ("circular dependency caused by with_clauses", N); Error_Msg_N ("\possibly missing limited_with clause" & " in one of the following", N); for U in Main_Unit .. Last_Unit loop if Context_Pending (Cunit (U)) then Error_Msg_Unit_1 := Get_Unit_Name (Unit (Cunit (U))); Error_Msg_N ("\unit$", N); end if; end loop; raise Unrecoverable_Error; end if; end; else Set_Context_Pending (N); end if; Analyze_Context (N); Set_Context_Pending (N, False); -- If the unit is a package body, the spec is already loaded and must be -- analyzed first, before we analyze the body. if Nkind (Unit_Node) = N_Package_Body then -- If no Lib_Unit, then there was a serious previous error, so just -- ignore the entire analysis effort if No (Lib_Unit) then return; else -- Analyze the package spec Semantics (Lib_Unit); -- Check for unused with's Check_Unused_Withs (Get_Cunit_Unit_Number (Lib_Unit)); -- Verify that the library unit is a package declaration if not Nkind_In (Unit (Lib_Unit), N_Package_Declaration, N_Generic_Package_Declaration) then Error_Msg_N ("no legal package declaration for package body", N); return; -- Otherwise, the entity in the declaration is visible. Update the -- version to reflect dependence of this body on the spec. else Spec_Id := Defining_Entity (Unit (Lib_Unit)); Set_Is_Immediately_Visible (Spec_Id, True); Version_Update (N, Lib_Unit); if Nkind (Defining_Unit_Name (Unit_Node)) = N_Defining_Program_Unit_Name then Generate_Parent_References (Unit_Node, Scope (Spec_Id)); end if; end if; end if; -- If the unit is a subprogram body, then we similarly need to analyze -- its spec. However, things are a little simpler in this case, because -- here, this analysis is done mostly for error checking and consistency -- purposes (but not only, e.g. there could be a contract on the spec), -- so there's nothing else to be done. elsif Nkind (Unit_Node) = N_Subprogram_Body then if Acts_As_Spec (N) then -- If the subprogram body is a child unit, we must create a -- declaration for it, in order to properly load the parent(s). -- After this, the original unit does not acts as a spec, because -- there is an explicit one. If this unit appears in a context -- clause, then an implicit with on the parent will be added when -- installing the context. If this is the main unit, there is no -- Unit_Table entry for the declaration (it has the unit number -- of the main unit) and code generation is unaffected. Unum := Get_Cunit_Unit_Number (N); Par_Spec_Name := Get_Parent_Spec_Name (Unit_Name (Unum)); if Par_Spec_Name /= No_Unit_Name then Unum := Load_Unit (Load_Name => Par_Spec_Name, Required => True, Subunit => False, Error_Node => N); if Unum /= No_Unit then -- Build subprogram declaration and attach parent unit to it -- This subprogram declaration does not come from source, -- Nevertheless the backend must generate debugging info for -- it, and this must be indicated explicitly. We also mark -- the body entity as a child unit now, to prevent a -- cascaded error if the spec entity cannot be entered -- in its scope. Finally we create a Units table entry for -- the subprogram declaration, to maintain a one-to-one -- correspondence with compilation unit nodes. This is -- critical for the tree traversals performed by CodePeer. declare Loc : constant Source_Ptr := Sloc (N); SCS : constant Boolean := Get_Comes_From_Source_Default; begin Set_Comes_From_Source_Default (False); -- Checks for redundant USE TYPE clauses have a special -- exception for the synthetic spec we create here. This -- special case relies on the two compilation units -- sharing the same context clause. -- Note: We used to do a shallow copy (New_Copy_List), -- which defeated those checks and also created malformed -- trees (subtype mark shared by two distinct -- N_Use_Type_Clause nodes) which crashed the compiler. Lib_Unit := Make_Compilation_Unit (Loc, Context_Items => Context_Items (N), Unit => Make_Subprogram_Declaration (Sloc (N), Specification => Copy_Separate_Tree (Specification (Unit_Node))), Aux_Decls_Node => Make_Compilation_Unit_Aux (Loc)); Set_Library_Unit (N, Lib_Unit); Set_Parent_Spec (Unit (Lib_Unit), Cunit (Unum)); Make_Child_Decl_Unit (N); Semantics (Lib_Unit); -- Now that a separate declaration exists, the body -- of the child unit does not act as spec any longer. Set_Acts_As_Spec (N, False); Set_Is_Child_Unit (Defining_Entity (Unit_Node)); Set_Debug_Info_Needed (Defining_Entity (Unit (Lib_Unit))); Set_Comes_From_Source_Default (SCS); end; end if; end if; -- Here for subprogram with separate declaration else Semantics (Lib_Unit); Check_Unused_Withs (Get_Cunit_Unit_Number (Lib_Unit)); Version_Update (N, Lib_Unit); end if; -- If this is a child unit, generate references to the parents if Nkind (Defining_Unit_Name (Specification (Unit_Node))) = N_Defining_Program_Unit_Name then Generate_Parent_References ( Specification (Unit_Node), Scope (Defining_Entity (Unit (Lib_Unit)))); end if; end if; -- If it is a child unit, the parent must be elaborated first and we -- update version, since we are dependent on our parent. if Is_Child_Spec (Unit_Node) then -- The analysis of the parent is done with style checks off declare Save_Style_Check : constant Boolean := Style_Check; begin if not GNAT_Mode then Style_Check := False; end if; Semantics (Parent_Spec (Unit_Node)); Version_Update (N, Parent_Spec (Unit_Node)); -- Restore style check settings Style_Check := Save_Style_Check; end; end if; -- With the analysis done, install the context. Note that we can't -- install the context from the with clauses as we analyze them, because -- each with clause must be analyzed in a clean visibility context, so -- we have to wait and install them all at once. Install_Context (N); if Is_Child_Spec (Unit_Node) then -- Set the entities of all parents in the program_unit_name Generate_Parent_References ( Unit_Node, Get_Parent_Entity (Unit (Parent_Spec (Unit_Node)))); end if; -- All components of the context: with-clauses, library unit, ancestors -- if any, (and their context) are analyzed and installed. -- Call special debug routine sm if this is the main unit if Current_Sem_Unit = Main_Unit then sm; end if; -- Now analyze the unit (package, subprogram spec, body) itself Analyze (Unit_Node); if Warn_On_Redundant_Constructs then Check_Redundant_Withs (Context_Items (N)); if Nkind (Unit_Node) = N_Package_Body then Check_Redundant_Withs (Context_Items => Context_Items (N), Spec_Context_Items => Context_Items (Lib_Unit)); end if; end if; -- The above call might have made Unit_Node an N_Subprogram_Body from -- something else, so propagate any Acts_As_Spec flag. if Nkind (Unit_Node) = N_Subprogram_Body and then Acts_As_Spec (Unit_Node) then Set_Acts_As_Spec (N); end if; -- Register predefined units in Rtsfind declare Unum : constant Unit_Number_Type := Get_Source_Unit (Sloc (N)); begin if Is_Predefined_File_Name (Unit_File_Name (Unum)) then Set_RTU_Loaded (Unit_Node); end if; end; -- Treat compilation unit pragmas that appear after the library unit if Present (Pragmas_After (Aux_Decls_Node (N))) then declare Prag_Node : Node_Id := First (Pragmas_After (Aux_Decls_Node (N))); begin while Present (Prag_Node) loop Analyze (Prag_Node); Next (Prag_Node); end loop; end; end if; -- Generate distribution stubs if requested and no error if N = Main_Cunit and then (Distribution_Stub_Mode = Generate_Receiver_Stub_Body or else Distribution_Stub_Mode = Generate_Caller_Stub_Body) and then not Fatal_Error (Main_Unit) then if Is_RCI_Pkg_Spec_Or_Body (N) then -- Regular RCI package Add_Stub_Constructs (N); elsif (Nkind (Unit_Node) = N_Package_Declaration and then Is_Shared_Passive (Defining_Entity (Specification (Unit_Node)))) or else (Nkind (Unit_Node) = N_Package_Body and then Is_Shared_Passive (Corresponding_Spec (Unit_Node))) then -- Shared passive package Add_Stub_Constructs (N); elsif Nkind (Unit_Node) = N_Package_Instantiation and then Is_Remote_Call_Interface (Defining_Entity (Specification (Instance_Spec (Unit_Node)))) then -- Instantiation of a RCI generic package Add_Stub_Constructs (N); end if; end if; -- Remove unit from visibility, so that environment is clean for the -- next compilation, which is either the main unit or some other unit -- in the context. if Nkind_In (Unit_Node, N_Package_Declaration, N_Package_Renaming_Declaration, N_Subprogram_Declaration) or else Nkind (Unit_Node) in N_Generic_Declaration or else (Nkind (Unit_Node) = N_Subprogram_Body and then Acts_As_Spec (Unit_Node)) then Remove_Unit_From_Visibility (Defining_Entity (Unit_Node)); -- If the unit is an instantiation whose body will be elaborated for -- inlining purposes, use the proper entity of the instance. The entity -- may be missing if the instantiation was illegal. elsif Nkind (Unit_Node) = N_Package_Instantiation and then not Error_Posted (Unit_Node) and then Present (Instance_Spec (Unit_Node)) then Remove_Unit_From_Visibility (Defining_Entity (Instance_Spec (Unit_Node))); elsif Nkind (Unit_Node) = N_Package_Body or else (Nkind (Unit_Node) = N_Subprogram_Body and then not Acts_As_Spec (Unit_Node)) then -- Bodies that are not the main unit are compiled if they are generic -- or contain generic or inlined units. Their analysis brings in the -- context of the corresponding spec (unit declaration) which must be -- removed as well, to return the compilation environment to its -- proper state. Remove_Context (Lib_Unit); Set_Is_Immediately_Visible (Defining_Entity (Unit (Lib_Unit)), False); end if; -- Last step is to deinstall the context we just installed as well as -- the unit just compiled. Remove_Context (N); -- If this is the main unit and we are generating code, we must check -- that all generic units in the context have a body if they need it, -- even if they have not been instantiated. In the absence of .ali files -- for generic units, we must force the load of the body, just to -- produce the proper error if the body is absent. We skip this -- verification if the main unit itself is generic. if Get_Cunit_Unit_Number (N) = Main_Unit and then Operating_Mode = Generate_Code and then Expander_Active then -- Check whether the source for the body of the unit must be included -- in a standalone library. Check_Body_Needed_For_SAL (Cunit_Entity (Main_Unit)); -- Indicate that the main unit is now analyzed, to catch possible -- circularities between it and generic bodies. Remove main unit from -- visibility. This might seem superfluous, but the main unit must -- not be visible in the generic body expansions that follow. Set_Analyzed (N, True); Set_Is_Immediately_Visible (Cunit_Entity (Main_Unit), False); declare Item : Node_Id; Nam : Entity_Id; Un : Unit_Number_Type; Save_Style_Check : constant Boolean := Style_Check; begin Item := First (Context_Items (N)); while Present (Item) loop -- Check for explicit with clause if Nkind (Item) = N_With_Clause and then not Implicit_With (Item) -- Ada 2005 (AI-50217): Ignore limited-withed units and then not Limited_Present (Item) then Nam := Entity (Name (Item)); -- Compile generic subprogram, unless it is intrinsic or -- imported so no body is required, or generic package body -- if the package spec requires a body. if (Is_Generic_Subprogram (Nam) and then not Is_Intrinsic_Subprogram (Nam) and then not Is_Imported (Nam)) or else (Ekind (Nam) = E_Generic_Package and then Unit_Requires_Body (Nam)) then Style_Check := False; if Present (Renamed_Object (Nam)) then Un := Load_Unit (Load_Name => Get_Body_Name (Get_Unit_Name (Unit_Declaration_Node (Renamed_Object (Nam)))), Required => False, Subunit => False, Error_Node => N, Renamings => True); else Un := Load_Unit (Load_Name => Get_Body_Name (Get_Unit_Name (Item)), Required => False, Subunit => False, Error_Node => N, Renamings => True); end if; if Un = No_Unit then Error_Msg_NE ("body of generic unit& not found", Item, Nam); exit; elsif not Analyzed (Cunit (Un)) and then Un /= Main_Unit and then not Fatal_Error (Un) then Style_Check := False; Semantics (Cunit (Un)); end if; end if; end if; Next (Item); end loop; -- Restore style checks settings Style_Check := Save_Style_Check; end; end if; -- Deal with creating elaboration Boolean if needed. We create an -- elaboration boolean only for units that come from source since -- units manufactured by the compiler never need elab checks. if Comes_From_Source (N) and then Nkind_In (Unit_Node, N_Package_Declaration, N_Generic_Package_Declaration, N_Subprogram_Declaration, N_Generic_Subprogram_Declaration) then declare Loc : constant Source_Ptr := Sloc (N); Unum : constant Unit_Number_Type := Get_Source_Unit (Loc); begin Spec_Id := Defining_Entity (Unit_Node); Generate_Definition (Spec_Id); -- See if an elaboration entity is required for possible access -- before elaboration checking. Note that we must allow for this -- even if -gnatE is not set, since a client may be compiled in -- -gnatE mode and reference the entity. -- These entities are also used by the binder to prevent multiple -- attempts to execute the elaboration code for the library case -- where the elaboration routine might otherwise be called more -- than once. -- Case of units which do not require elaboration checks if -- Pure units do not need checks Is_Pure (Spec_Id) -- Preelaborated units do not need checks or else Is_Preelaborated (Spec_Id) -- No checks needed if pragma Elaborate_Body present or else Has_Pragma_Elaborate_Body (Spec_Id) -- No checks needed if unit does not require a body or else not Unit_Requires_Body (Spec_Id) -- No checks needed for predefined files or else Is_Predefined_File_Name (Unit_File_Name (Unum)) -- No checks required if no separate spec or else Acts_As_Spec (N) then -- This is a case where we only need the entity for -- checking to prevent multiple elaboration checks. Set_Elaboration_Entity_Required (Spec_Id, False); -- Case of elaboration entity is required for access before -- elaboration checking (so certainly we must build it!) else Set_Elaboration_Entity_Required (Spec_Id, True); end if; Build_Elaboration_Entity (N, Spec_Id); end; end if; -- Freeze the compilation unit entity. This for sure is needed because -- of some warnings that can be output (see Freeze_Subprogram), but may -- in general be required. If freezing actions result, place them in the -- compilation unit actions list, and analyze them. declare L : constant List_Id := Freeze_Entity (Cunit_Entity (Current_Sem_Unit), N); begin while Is_Non_Empty_List (L) loop Insert_Library_Level_Action (Remove_Head (L)); end loop; end; Set_Analyzed (N); if Nkind (Unit_Node) = N_Package_Declaration and then Get_Cunit_Unit_Number (N) /= Main_Unit and then Expander_Active then declare Save_Style_Check : constant Boolean := Style_Check; Save_Warning : constant Warning_Mode_Type := Warning_Mode; Options : Style_Check_Options; begin Save_Style_Check_Options (Options); Reset_Style_Check_Options; Opt.Warning_Mode := Suppress; Check_Body_For_Inlining (N, Defining_Entity (Unit_Node)); Reset_Style_Check_Options; Set_Style_Check_Options (Options); Style_Check := Save_Style_Check; Warning_Mode := Save_Warning; end; end if; -- If we are generating obsolescent warnings, then here is where we -- generate them for the with'ed items. The reason for this special -- processing is that the normal mechanism of generating the warnings -- for referenced entities does not work for context clause references. -- That's because when we first analyze the context, it is too early to -- know if the with'ing unit is itself obsolescent (which suppresses -- the warnings). if not GNAT_Mode and then Warn_On_Obsolescent_Feature then -- Push current compilation unit as scope, so that the test for -- being within an obsolescent unit will work correctly. Push_Scope (Defining_Entity (Unit_Node)); -- Loop through context items to deal with with clauses declare Item : Node_Id; Nam : Node_Id; Ent : Entity_Id; begin Item := First (Context_Items (N)); while Present (Item) loop if Nkind (Item) = N_With_Clause -- Suppress this check in limited-withed units. Further work -- needed here if we decide to incorporate this check on -- limited-withed units. and then not Limited_Present (Item) then Nam := Name (Item); Ent := Entity (Nam); if Is_Obsolescent (Ent) then Output_Obsolescent_Entity_Warnings (Nam, Ent); end if; end if; Next (Item); end loop; end; -- Remove temporary install of current unit as scope Pop_Scope; end if; end Analyze_Compilation_Unit; --------------------- -- Analyze_Context -- --------------------- procedure Analyze_Context (N : Node_Id) is Ukind : constant Node_Kind := Nkind (Unit (N)); Item : Node_Id; begin -- First process all configuration pragmas at the start of the context -- items. Strictly these are not part of the context clause, but that -- is where the parser puts them. In any case for sure we must analyze -- these before analyzing the actual context items, since they can have -- an effect on that analysis (e.g. pragma Ada_2005 may allow a unit to -- be with'ed as a result of changing categorizations in Ada 2005). Item := First (Context_Items (N)); while Present (Item) and then Nkind (Item) = N_Pragma and then Pragma_Name (Item) in Configuration_Pragma_Names loop Analyze (Item); Next (Item); end loop; -- This is the point at which we capture the configuration settings -- for the unit. At the moment only the Optimize_Alignment setting -- needs to be captured. Probably more later ??? if Optimize_Alignment_Local then Set_OA_Setting (Current_Sem_Unit, 'L'); else Set_OA_Setting (Current_Sem_Unit, Optimize_Alignment); end if; -- Loop through actual context items. This is done in two passes: -- a) The first pass analyzes non-limited with-clauses and also any -- configuration pragmas (we need to get the latter analyzed right -- away, since they can affect processing of subsequent items. -- b) The second pass analyzes limited_with clauses (Ada 2005: AI-50217) while Present (Item) loop -- For with clause, analyze the with clause, and then update the -- version, since we are dependent on a unit that we with. if Nkind (Item) = N_With_Clause and then not Limited_Present (Item) then -- Skip analyzing with clause if no unit, nothing to do (this -- happens for a with that references a non-existent unit). Skip -- as well if this is a with_clause for the main unit, which -- happens if a subunit has a useless with_clause on its parent. if Present (Library_Unit (Item)) then if Library_Unit (Item) /= Cunit (Current_Sem_Unit) then Analyze (Item); else Set_Entity (Name (Item), Cunit_Entity (Current_Sem_Unit)); end if; end if; if not Implicit_With (Item) then Version_Update (N, Library_Unit (Item)); end if; -- Skip pragmas. Configuration pragmas at the start were handled in -- the loop above, and remaining pragmas are not processed until we -- actually install the context (see Install_Context). We delay the -- analysis of these pragmas to make sure that we have installed all -- the implicit with's on parent units. -- Skip use clauses at this stage, since we don't want to do any -- installing of potentially use-visible entities until we -- actually install the complete context (in Install_Context). -- Otherwise things can get installed in the wrong context. else null; end if; Next (Item); end loop; -- Second pass: examine all limited_with clauses. All other context -- items are ignored in this pass. Item := First (Context_Items (N)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Limited_Present (Item) then -- No need to check errors on implicitly generated limited-with -- clauses. if not Implicit_With (Item) then -- Verify that the illegal contexts given in 10.1.2 (18/2) are -- properly rejected, including renaming declarations. if not Nkind_In (Ukind, N_Package_Declaration, N_Subprogram_Declaration) and then Ukind not in N_Generic_Declaration and then Ukind not in N_Generic_Instantiation then Error_Msg_N ("limited with_clause not allowed here", Item); -- Check wrong use of a limited with clause applied to the -- compilation unit containing the limited-with clause. -- limited with P.Q; -- package P.Q is ... elsif Unit (Library_Unit (Item)) = Unit (N) then Error_Msg_N ("wrong use of limited-with clause", Item); -- Check wrong use of limited-with clause applied to some -- immediate ancestor. elsif Is_Child_Spec (Unit (N)) then declare Lib_U : constant Entity_Id := Unit (Library_Unit (Item)); P : Node_Id; begin P := Parent_Spec (Unit (N)); loop if Unit (P) = Lib_U then Error_Msg_N ("limited with_clause cannot " & "name ancestor", Item); exit; end if; exit when not Is_Child_Spec (Unit (P)); P := Parent_Spec (Unit (P)); end loop; end; end if; -- Check if the limited-withed unit is already visible through -- some context clause of the current compilation unit or some -- ancestor of the current compilation unit. declare Lim_Unit_Name : constant Node_Id := Name (Item); Comp_Unit : Node_Id; It : Node_Id; Unit_Name : Node_Id; begin Comp_Unit := N; loop It := First (Context_Items (Comp_Unit)); while Present (It) loop if Item /= It and then Nkind (It) = N_With_Clause and then not Limited_Present (It) and then Nkind_In (Unit (Library_Unit (It)), N_Package_Declaration, N_Package_Renaming_Declaration) then if Nkind (Unit (Library_Unit (It))) = N_Package_Declaration then Unit_Name := Name (It); else Unit_Name := Name (Unit (Library_Unit (It))); end if; -- Check if the named package (or some ancestor) -- leaves visible the full-view of the unit given -- in the limited-with clause loop if Designate_Same_Unit (Lim_Unit_Name, Unit_Name) then Error_Msg_Sloc := Sloc (It); Error_Msg_N ("simultaneous visibility of limited " & "and unlimited views not allowed", Item); Error_Msg_NE ("\unlimited view visible through " & "context clause #", Item, It); exit; elsif Nkind (Unit_Name) = N_Identifier then exit; end if; Unit_Name := Prefix (Unit_Name); end loop; end if; Next (It); end loop; exit when not Is_Child_Spec (Unit (Comp_Unit)); Comp_Unit := Parent_Spec (Unit (Comp_Unit)); end loop; end; end if; -- Skip analyzing with clause if no unit, see above if Present (Library_Unit (Item)) then Analyze (Item); end if; -- A limited_with does not impose an elaboration order, but -- there is a semantic dependency for recompilation purposes. if not Implicit_With (Item) then Version_Update (N, Library_Unit (Item)); end if; -- Pragmas and use clauses and with clauses other than limited -- with's are ignored in this pass through the context items. else null; end if; Next (Item); end loop; end Analyze_Context; ------------------------------- -- Analyze_Package_Body_Stub -- ------------------------------- procedure Analyze_Package_Body_Stub (N : Node_Id) is Id : constant Entity_Id := Defining_Identifier (N); Nam : Entity_Id; begin -- The package declaration must be in the current declarative part Check_Stub_Level (N); Nam := Current_Entity_In_Scope (Id); if No (Nam) or else not Is_Package_Or_Generic_Package (Nam) then Error_Msg_N ("missing specification for package stub", N); elsif Has_Completion (Nam) and then Present (Corresponding_Body (Unit_Declaration_Node (Nam))) then Error_Msg_N ("duplicate or redundant stub for package", N); else -- Indicate that the body of the package exists. If we are doing -- only semantic analysis, the stub stands for the body. If we are -- generating code, the existence of the body will be confirmed -- when we load the proper body. Set_Has_Completion (Nam); Set_Scope (Defining_Entity (N), Current_Scope); Generate_Reference (Nam, Id, 'b'); Analyze_Proper_Body (N, Nam); end if; end Analyze_Package_Body_Stub; ------------------------- -- Analyze_Proper_Body -- ------------------------- procedure Analyze_Proper_Body (N : Node_Id; Nam : Entity_Id) is Subunit_Name : constant Unit_Name_Type := Get_Unit_Name (N); Unum : Unit_Number_Type; procedure Optional_Subunit; -- This procedure is called when the main unit is a stub, or when we -- are not generating code. In such a case, we analyze the subunit if -- present, which is user-friendly and in fact required for ASIS, but -- we don't complain if the subunit is missing. ---------------------- -- Optional_Subunit -- ---------------------- procedure Optional_Subunit is Comp_Unit : Node_Id; begin -- Try to load subunit, but ignore any errors that occur during the -- loading of the subunit, by using the special feature in Errout to -- ignore all errors. Note that Fatal_Error will still be set, so we -- will be able to check for this case below. if not ASIS_Mode then Ignore_Errors_Enable := Ignore_Errors_Enable + 1; end if; Unum := Load_Unit (Load_Name => Subunit_Name, Required => False, Subunit => True, Error_Node => N); if not ASIS_Mode then Ignore_Errors_Enable := Ignore_Errors_Enable - 1; end if; -- All done if we successfully loaded the subunit if Unum /= No_Unit and then (not Fatal_Error (Unum) or else Try_Semantics) then Comp_Unit := Cunit (Unum); -- If the file was empty or seriously mangled, the unit itself may -- be missing. if No (Unit (Comp_Unit)) then Error_Msg_N ("subunit does not contain expected proper body", N); elsif Nkind (Unit (Comp_Unit)) /= N_Subunit then Error_Msg_N ("expected SEPARATE subunit, found child unit", Cunit_Entity (Unum)); else Set_Corresponding_Stub (Unit (Comp_Unit), N); Analyze_Subunit (Comp_Unit); Set_Library_Unit (N, Comp_Unit); end if; elsif Unum = No_Unit and then Present (Nam) then if Is_Protected_Type (Nam) then Set_Corresponding_Body (Parent (Nam), Defining_Identifier (N)); else Set_Corresponding_Body ( Unit_Declaration_Node (Nam), Defining_Identifier (N)); end if; end if; end Optional_Subunit; -- Start of processing for Analyze_Proper_Body begin -- If the subunit is already loaded, it means that the main unit is a -- subunit, and that the current unit is one of its parents which was -- being analyzed to provide the needed context for the analysis of the -- subunit. In this case we analyze the subunit and continue with the -- parent, without looking at subsequent subunits. if Is_Loaded (Subunit_Name) then -- If the proper body is already linked to the stub node, the stub is -- in a generic unit and just needs analyzing. if Present (Library_Unit (N)) then Set_Corresponding_Stub (Unit (Library_Unit (N)), N); -- If the subunit has severe errors, the spec of the enclosing -- body may not be available, in which case do not try analysis. if Serious_Errors_Detected > 0 and then No (Library_Unit (Library_Unit (N))) then return; end if; Analyze_Subunit (Library_Unit (N)); -- Otherwise we must load the subunit and link to it else -- Load the subunit, this must work, since we originally loaded -- the subunit earlier on. So this will not really load it, just -- give access to it. Unum := Load_Unit (Load_Name => Subunit_Name, Required => True, Subunit => False, Error_Node => N); -- And analyze the subunit in the parent context (note that we -- do not call Semantics, since that would remove the parent -- context). Because of this, we have to manually reset the -- compiler state to Analyzing since it got destroyed by Load. if Unum /= No_Unit then Compiler_State := Analyzing; -- Check that the proper body is a subunit and not a child -- unit. If the unit was previously loaded, the error will -- have been emitted when copying the generic node, so we -- just return to avoid cascaded errors. if Nkind (Unit (Cunit (Unum))) /= N_Subunit then return; end if; Set_Corresponding_Stub (Unit (Cunit (Unum)), N); Analyze_Subunit (Cunit (Unum)); Set_Library_Unit (N, Cunit (Unum)); end if; end if; -- If the main unit is a subunit, then we are just performing semantic -- analysis on that subunit, and any other subunits of any parent unit -- should be ignored, except that if we are building trees for ASIS -- usage we want to annotate the stub properly. elsif Nkind (Unit (Cunit (Main_Unit))) = N_Subunit and then Subunit_Name /= Unit_Name (Main_Unit) then if ASIS_Mode then Optional_Subunit; end if; -- But before we return, set the flag for unloaded subunits. This -- will suppress junk warnings of variables in the same declarative -- part (or a higher level one) that are in danger of looking unused -- when in fact there might be a declaration in the subunit that we -- do not intend to load. Unloaded_Subunits := True; return; -- If the subunit is not already loaded, and we are generating code, -- then this is the case where compilation started from the parent, and -- we are generating code for an entire subunit tree. In that case we -- definitely need to load the subunit. -- In order to continue the analysis with the rest of the parent, -- and other subunits, we load the unit without requiring its -- presence, and emit a warning if not found, rather than terminating -- the compilation abruptly, as for other missing file problems. elsif Original_Operating_Mode = Generate_Code then -- If the proper body is already linked to the stub node, the stub is -- in a generic unit and just needs analyzing. -- We update the version. Although we are not strictly technically -- semantically dependent on the subunit, given our approach of macro -- substitution of subunits, it makes sense to include it in the -- version identification. if Present (Library_Unit (N)) then Set_Corresponding_Stub (Unit (Library_Unit (N)), N); Analyze_Subunit (Library_Unit (N)); Version_Update (Cunit (Main_Unit), Library_Unit (N)); -- Otherwise we must load the subunit and link to it else -- Make sure that, if the subunit is preprocessed and -gnateG is -- specified, the preprocessed file will be written. Lib.Analysing_Subunit_Of_Main := True; Unum := Load_Unit (Load_Name => Subunit_Name, Required => False, Subunit => True, Error_Node => N); Lib.Analysing_Subunit_Of_Main := False; -- Give message if we did not get the unit Emit warning even if -- missing subunit is not within main unit, to simplify debugging. if Original_Operating_Mode = Generate_Code and then Unum = No_Unit then Error_Msg_Unit_1 := Subunit_Name; Error_Msg_File_1 := Get_File_Name (Subunit_Name, Subunit => True); Error_Msg_N ("subunit$$ in file{ not found?!!", N); Subunits_Missing := True; end if; -- Load_Unit may reset Compiler_State, since it may have been -- necessary to parse an additional units, so we make sure that -- we reset it to the Analyzing state. Compiler_State := Analyzing; if Unum /= No_Unit then if Debug_Flag_L then Write_Str ("*** Loaded subunit from stub. Analyze"); Write_Eol; end if; declare Comp_Unit : constant Node_Id := Cunit (Unum); begin -- Check for child unit instead of subunit if Nkind (Unit (Comp_Unit)) /= N_Subunit then Error_Msg_N ("expected SEPARATE subunit, found child unit", Cunit_Entity (Unum)); -- OK, we have a subunit else -- Set corresponding stub (even if errors) Set_Corresponding_Stub (Unit (Comp_Unit), N); -- Collect SCO information for loaded subunit if we are -- in the main unit). if Generate_SCO and then In_Extended_Main_Source_Unit (Cunit_Entity (Current_Sem_Unit)) then SCO_Record (Unum); end if; -- Analyze the unit if semantics active if not Fatal_Error (Unum) or else Try_Semantics then Analyze_Subunit (Comp_Unit); end if; -- Set the library unit pointer in any case Set_Library_Unit (N, Comp_Unit); -- We update the version. Although we are not technically -- semantically dependent on the subunit, given our -- approach of macro substitution of subunits, it makes -- sense to include it in the version identification. Version_Update (Cunit (Main_Unit), Comp_Unit); end if; end; end if; end if; -- The remaining case is when the subunit is not already loaded and we -- are not generating code. In this case we are just performing semantic -- analysis on the parent, and we are not interested in the subunit. For -- subprograms, analyze the stub as a body. For other entities the stub -- has already been marked as completed. else Optional_Subunit; end if; end Analyze_Proper_Body; ---------------------------------- -- Analyze_Protected_Body_Stub -- ---------------------------------- procedure Analyze_Protected_Body_Stub (N : Node_Id) is Nam : Entity_Id := Current_Entity_In_Scope (Defining_Identifier (N)); begin Check_Stub_Level (N); -- First occurrence of name may have been as an incomplete type if Present (Nam) and then Ekind (Nam) = E_Incomplete_Type then Nam := Full_View (Nam); end if; if No (Nam) or else not Is_Protected_Type (Etype (Nam)) then Error_Msg_N ("missing specification for Protected body", N); else Set_Scope (Defining_Entity (N), Current_Scope); Set_Has_Completion (Etype (Nam)); Generate_Reference (Nam, Defining_Identifier (N), 'b'); Analyze_Proper_Body (N, Etype (Nam)); end if; end Analyze_Protected_Body_Stub; ---------------------------------- -- Analyze_Subprogram_Body_Stub -- ---------------------------------- -- A subprogram body stub can appear with or without a previous spec. If -- there is one, then the analysis of the body will find it and verify -- conformance. The formals appearing in the specification of the stub play -- no role, except for requiring an additional conformance check. If there -- is no previous subprogram declaration, the stub acts as a spec, and -- provides the defining entity for the subprogram. procedure Analyze_Subprogram_Body_Stub (N : Node_Id) is Decl : Node_Id; begin Check_Stub_Level (N); -- Verify that the identifier for the stub is unique within this -- declarative part. if Nkind_In (Parent (N), N_Block_Statement, N_Package_Body, N_Subprogram_Body) then Decl := First (Declarations (Parent (N))); while Present (Decl) and then Decl /= N loop if Nkind (Decl) = N_Subprogram_Body_Stub and then (Chars (Defining_Unit_Name (Specification (Decl))) = Chars (Defining_Unit_Name (Specification (N)))) then Error_Msg_N ("identifier for stub is not unique", N); end if; Next (Decl); end loop; end if; -- Treat stub as a body, which checks conformance if there is a previous -- declaration, or else introduces entity and its signature. Analyze_Subprogram_Body (N); Analyze_Proper_Body (N, Empty); end Analyze_Subprogram_Body_Stub; --------------------- -- Analyze_Subunit -- --------------------- -- A subunit is compiled either by itself (for semantic checking) or as -- part of compiling the parent (for code generation). In either case, by -- the time we actually process the subunit, the parent has already been -- installed and analyzed. The node N is a compilation unit, whose context -- needs to be treated here, because we come directly here from the parent -- without calling Analyze_Compilation_Unit. -- The compilation context includes the explicit context of the subunit, -- and the context of the parent, together with the parent itself. In order -- to compile the current context, we remove the one inherited from the -- parent, in order to have a clean visibility table. We restore the parent -- context before analyzing the proper body itself. On exit, we remove only -- the explicit context of the subunit. procedure Analyze_Subunit (N : Node_Id) is Lib_Unit : constant Node_Id := Library_Unit (N); Par_Unit : constant Entity_Id := Current_Scope; Lib_Spec : Node_Id := Library_Unit (Lib_Unit); Num_Scopes : Int := 0; Use_Clauses : array (1 .. Scope_Stack.Last) of Node_Id; Enclosing_Child : Entity_Id := Empty; Svg : constant Suppress_Array := Scope_Suppress; Save_Cunit_Restrictions : constant Save_Cunit_Boolean_Restrictions := Cunit_Boolean_Restrictions_Save; -- Save non-partition wide restrictions before processing the subunit. -- All subunits are analyzed with config restrictions reset and we need -- to restore these saved values at the end. procedure Analyze_Subunit_Context; -- Capture names in use clauses of the subunit. This must be done before -- re-installing parent declarations, because items in the context must -- not be hidden by declarations local to the parent. procedure Re_Install_Parents (L : Node_Id; Scop : Entity_Id); -- Recursive procedure to restore scope of all ancestors of subunit, -- from outermost in. If parent is not a subunit, the call to install -- context installs context of spec and (if parent is a child unit) the -- context of its parents as well. It is confusing that parents should -- be treated differently in both cases, but the semantics are just not -- identical. procedure Re_Install_Use_Clauses; -- As part of the removal of the parent scope, the use clauses are -- removed, to be reinstalled when the context of the subunit has been -- analyzed. Use clauses may also have been affected by the analysis of -- the context of the subunit, so they have to be applied again, to -- insure that the compilation environment of the rest of the parent -- unit is identical. procedure Remove_Scope; -- Remove current scope from scope stack, and preserve the list of use -- clauses in it, to be reinstalled after context is analyzed. ----------------------------- -- Analyze_Subunit_Context -- ----------------------------- procedure Analyze_Subunit_Context is Item : Node_Id; Nam : Node_Id; Unit_Name : Entity_Id; begin Analyze_Context (N); -- Make withed units immediately visible. If child unit, make the -- ultimate parent immediately visible. Item := First (Context_Items (N)); while Present (Item) loop if Nkind (Item) = N_With_Clause then -- Protect frontend against previous errors in context clauses if Nkind (Name (Item)) /= N_Selected_Component then if Error_Posted (Item) then null; else -- If a subunits has serious syntax errors, the context -- may not have been loaded. Add a harmless unit name to -- attempt processing. if Serious_Errors_Detected > 0 and then No (Entity (Name (Item))) then Set_Entity (Name (Item), Standard_Standard); end if; Unit_Name := Entity (Name (Item)); while Is_Child_Unit (Unit_Name) loop Set_Is_Visible_Child_Unit (Unit_Name); Unit_Name := Scope (Unit_Name); end loop; if not Is_Immediately_Visible (Unit_Name) then Set_Is_Immediately_Visible (Unit_Name); Set_Context_Installed (Item); end if; end if; end if; elsif Nkind (Item) = N_Use_Package_Clause then Nam := First (Names (Item)); while Present (Nam) loop Analyze (Nam); Next (Nam); end loop; elsif Nkind (Item) = N_Use_Type_Clause then Nam := First (Subtype_Marks (Item)); while Present (Nam) loop Analyze (Nam); Next (Nam); end loop; end if; Next (Item); end loop; -- Reset visibility of withed units. They will be made visible again -- when we install the subunit context. Item := First (Context_Items (N)); while Present (Item) loop if Nkind (Item) = N_With_Clause -- Protect frontend against previous errors in context clauses and then Nkind (Name (Item)) /= N_Selected_Component and then not Error_Posted (Item) then Unit_Name := Entity (Name (Item)); while Is_Child_Unit (Unit_Name) loop Set_Is_Visible_Child_Unit (Unit_Name, False); Unit_Name := Scope (Unit_Name); end loop; if Context_Installed (Item) then Set_Is_Immediately_Visible (Unit_Name, False); Set_Context_Installed (Item, False); end if; end if; Next (Item); end loop; end Analyze_Subunit_Context; ------------------------ -- Re_Install_Parents -- ------------------------ procedure Re_Install_Parents (L : Node_Id; Scop : Entity_Id) is E : Entity_Id; begin if Nkind (Unit (L)) = N_Subunit then Re_Install_Parents (Library_Unit (L), Scope (Scop)); end if; Install_Context (L); -- If the subunit occurs within a child unit, we must restore the -- immediate visibility of any siblings that may occur in context. if Present (Enclosing_Child) then Install_Siblings (Enclosing_Child, L); end if; Push_Scope (Scop); if Scop /= Par_Unit then Set_Is_Immediately_Visible (Scop); end if; -- Make entities in scope visible again. For child units, restore -- visibility only if they are actually in context. E := First_Entity (Current_Scope); while Present (E) loop if not Is_Child_Unit (E) or else Is_Visible_Child_Unit (E) then Set_Is_Immediately_Visible (E); end if; Next_Entity (E); end loop; -- A subunit appears within a body, and for a nested subunits all the -- parents are bodies. Restore full visibility of their private -- entities. if Is_Package_Or_Generic_Package (Scop) then Set_In_Package_Body (Scop); Install_Private_Declarations (Scop); end if; end Re_Install_Parents; ---------------------------- -- Re_Install_Use_Clauses -- ---------------------------- procedure Re_Install_Use_Clauses is U : Node_Id; begin for J in reverse 1 .. Num_Scopes loop U := Use_Clauses (J); Scope_Stack.Table (Scope_Stack.Last - J + 1).First_Use_Clause := U; Install_Use_Clauses (U, Force_Installation => True); end loop; end Re_Install_Use_Clauses; ------------------ -- Remove_Scope -- ------------------ procedure Remove_Scope is E : Entity_Id; begin Num_Scopes := Num_Scopes + 1; Use_Clauses (Num_Scopes) := Scope_Stack.Table (Scope_Stack.Last).First_Use_Clause; E := First_Entity (Current_Scope); while Present (E) loop Set_Is_Immediately_Visible (E, False); Next_Entity (E); end loop; if Is_Child_Unit (Current_Scope) then Enclosing_Child := Current_Scope; end if; Pop_Scope; end Remove_Scope; -- Start of processing for Analyze_Subunit begin -- For subunit in main extended unit, we reset the configuration values -- for the non-partition-wide restrictions. For other units reset them. if In_Extended_Main_Source_Unit (N) then Restore_Config_Cunit_Boolean_Restrictions; else Reset_Cunit_Boolean_Restrictions; end if; if Style_Check then declare Nam : Node_Id := Name (Unit (N)); begin if Nkind (Nam) = N_Selected_Component then Nam := Selector_Name (Nam); end if; Check_Identifier (Nam, Par_Unit); end; end if; if not Is_Empty_List (Context_Items (N)) then -- Save current use clauses Remove_Scope; Remove_Context (Lib_Unit); -- Now remove parents and their context, including enclosing subunits -- and the outer parent body which is not a subunit. if Present (Lib_Spec) then Remove_Context (Lib_Spec); while Nkind (Unit (Lib_Spec)) = N_Subunit loop Lib_Spec := Library_Unit (Lib_Spec); Remove_Scope; Remove_Context (Lib_Spec); end loop; if Nkind (Unit (Lib_Unit)) = N_Subunit then Remove_Scope; end if; if Nkind (Unit (Lib_Spec)) = N_Package_Body then Remove_Context (Library_Unit (Lib_Spec)); end if; end if; Set_Is_Immediately_Visible (Par_Unit, False); Analyze_Subunit_Context; Re_Install_Parents (Lib_Unit, Par_Unit); Set_Is_Immediately_Visible (Par_Unit); -- If the context includes a child unit of the parent of the subunit, -- the parent will have been removed from visibility, after compiling -- that cousin in the context. The visibility of the parent must be -- restored now. This also applies if the context includes another -- subunit of the same parent which in turn includes a child unit in -- its context. if Is_Package_Or_Generic_Package (Par_Unit) then if not Is_Immediately_Visible (Par_Unit) or else (Present (First_Entity (Par_Unit)) and then not Is_Immediately_Visible (First_Entity (Par_Unit))) then Set_Is_Immediately_Visible (Par_Unit); Install_Visible_Declarations (Par_Unit); Install_Private_Declarations (Par_Unit); end if; end if; Re_Install_Use_Clauses; Install_Context (N); -- Restore state of suppress flags for current body Scope_Suppress := Svg; -- If the subunit is within a child unit, then siblings of any parent -- unit that appear in the context clause of the subunit must also be -- made immediately visible. if Present (Enclosing_Child) then Install_Siblings (Enclosing_Child, N); end if; end if; Analyze (Proper_Body (Unit (N))); Remove_Context (N); -- The subunit may contain a with_clause on a sibling of some ancestor. -- Removing the context will remove from visibility those ancestor child -- units, which must be restored to the visibility they have in the -- enclosing body. if Present (Enclosing_Child) then declare C : Entity_Id; begin C := Current_Scope; while Present (C) and then Is_Child_Unit (C) loop Set_Is_Immediately_Visible (C); Set_Is_Visible_Child_Unit (C); C := Scope (C); end loop; end; end if; -- Deal with restore of restrictions Cunit_Boolean_Restrictions_Restore (Save_Cunit_Restrictions); end Analyze_Subunit; ---------------------------- -- Analyze_Task_Body_Stub -- ---------------------------- procedure Analyze_Task_Body_Stub (N : Node_Id) is Nam : Entity_Id := Current_Entity_In_Scope (Defining_Identifier (N)); Loc : constant Source_Ptr := Sloc (N); begin Check_Stub_Level (N); -- First occurrence of name may have been as an incomplete type if Present (Nam) and then Ekind (Nam) = E_Incomplete_Type then Nam := Full_View (Nam); end if; if No (Nam) or else not Is_Task_Type (Etype (Nam)) then Error_Msg_N ("missing specification for task body", N); else Set_Scope (Defining_Entity (N), Current_Scope); Generate_Reference (Nam, Defining_Identifier (N), 'b'); -- Check for duplicate stub, if so give message and terminate if Has_Completion (Etype (Nam)) then Error_Msg_N ("duplicate stub for task", N); return; else Set_Has_Completion (Etype (Nam)); end if; Analyze_Proper_Body (N, Etype (Nam)); -- Set elaboration flag to indicate that entity is callable. This -- cannot be done in the expansion of the body itself, because the -- proper body is not in a declarative part. This is only done if -- expansion is active, because the context may be generic and the -- flag not defined yet. if Full_Expander_Active then Insert_After (N, Make_Assignment_Statement (Loc, Name => Make_Identifier (Loc, Chars => New_External_Name (Chars (Etype (Nam)), 'E')), Expression => New_Reference_To (Standard_True, Loc))); end if; end if; end Analyze_Task_Body_Stub; ------------------------- -- Analyze_With_Clause -- ------------------------- -- Analyze the declaration of a unit in a with clause. At end, label the -- with clause with the defining entity for the unit. procedure Analyze_With_Clause (N : Node_Id) is -- Retrieve the original kind of the unit node, before analysis. If it -- is a subprogram instantiation, its analysis below will rewrite the -- node as the declaration of the wrapper package. If the same -- instantiation appears indirectly elsewhere in the context, it will -- have been analyzed already. Unit_Kind : constant Node_Kind := Nkind (Original_Node (Unit (Library_Unit (N)))); Nam : constant Node_Id := Name (N); E_Name : Entity_Id; Par_Name : Entity_Id; Pref : Node_Id; U : Node_Id; Intunit : Boolean; -- Set True if the unit currently being compiled is an internal unit Restriction_Violation : Boolean := False; -- Set True if a with violates a restriction, no point in giving any -- warnings if we have this definite error. Save_Style_Check : constant Boolean := Opt.Style_Check; begin U := Unit (Library_Unit (N)); -- If this is an internal unit which is a renaming, then this is a -- violation of No_Obsolescent_Features. -- Note: this is not quite right if the user defines one of these units -- himself, but that's a marginal case, and fixing it is hard ??? if Restriction_Check_Required (No_Obsolescent_Features) then declare F : constant File_Name_Type := Unit_File_Name (Get_Source_Unit (U)); begin if Is_Predefined_File_Name (F, Renamings_Included => True) and then not Is_Predefined_File_Name (F, Renamings_Included => False) then Check_Restriction (No_Obsolescent_Features, N); Restriction_Violation := True; end if; end; end if; -- Check No_Implementation_Units violation if Restriction_Check_Required (No_Implementation_Units) then if Not_Impl_Defined_Unit (Get_Source_Unit (U)) then null; else Check_Restriction (No_Implementation_Units, Nam); Restriction_Violation := True; end if; end if; -- Several actions are skipped for dummy packages (those supplied for -- with's where no matching file could be found). Such packages are -- identified by the Sloc value being set to No_Location. if Limited_Present (N) then -- Ada 2005 (AI-50217): Build visibility structures but do not -- analyze the unit. if Sloc (U) /= No_Location then Build_Limited_Views (N); end if; return; end if; -- We reset ordinary style checking during the analysis of a with'ed -- unit, but we do NOT reset GNAT special analysis mode (the latter -- definitely *does* apply to with'ed units). if not GNAT_Mode then Style_Check := False; end if; -- If the library unit is a predefined unit, and we are in high -- integrity mode, then temporarily reset Configurable_Run_Time_Mode -- for the analysis of the with'ed unit. This mode does not prevent -- explicit with'ing of run-time units. if Configurable_Run_Time_Mode and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (U))) then Configurable_Run_Time_Mode := False; Semantics (Library_Unit (N)); Configurable_Run_Time_Mode := True; else Semantics (Library_Unit (N)); end if; Intunit := Is_Internal_File_Name (Unit_File_Name (Current_Sem_Unit)); if Sloc (U) /= No_Location then -- Check restrictions, except that we skip the check if this is an -- internal unit unless we are compiling the internal unit as the -- main unit. We also skip this for dummy packages. Check_Restriction_No_Dependence (Nam, N); if not Intunit or else Current_Sem_Unit = Main_Unit then Check_Restricted_Unit (Unit_Name (Get_Source_Unit (U)), N); end if; -- Deal with special case of GNAT.Current_Exceptions which interacts -- with the optimization of local raise statements into gotos. if Nkind (Nam) = N_Selected_Component and then Nkind (Prefix (Nam)) = N_Identifier and then Chars (Prefix (Nam)) = Name_Gnat and then (Chars (Selector_Name (Nam)) = Name_Most_Recent_Exception or else Chars (Selector_Name (Nam)) = Name_Exception_Traces) then Check_Restriction (No_Exception_Propagation, N); Special_Exception_Package_Used := True; end if; -- Check for inappropriate with of internal implementation unit if we -- are not compiling an internal unit and also check for withing unit -- in wrong version of Ada. Do not issue these messages for implicit -- with's generated by the compiler itself. if Implementation_Unit_Warnings and then not Intunit and then not Implicit_With (N) and then not Restriction_Violation then declare U_Kind : constant Kind_Of_Unit := Get_Kind_Of_Unit (Get_Source_Unit (U)); begin if U_Kind = Implementation_Unit then Error_Msg_F ("& is an internal 'G'N'A'T unit?", Name (N)); -- Add alternative name if available, otherwise issue a -- general warning message. if Error_Msg_Strlen /= 0 then Error_Msg_F ("\use ""~"" instead", Name (N)); else Error_Msg_F ("\use of this unit is non-portable " & "and version-dependent?", Name (N)); end if; elsif U_Kind = Ada_2005_Unit and then Ada_Version < Ada_2005 and then Warn_On_Ada_2005_Compatibility then Error_Msg_N ("& is an Ada 2005 unit?", Name (N)); elsif U_Kind = Ada_2012_Unit and then Ada_Version < Ada_2012 and then Warn_On_Ada_2012_Compatibility then Error_Msg_N ("& is an Ada 2012 unit?", Name (N)); end if; end; end if; end if; -- Semantic analysis of a generic unit is performed on a copy of -- the original tree. Retrieve the entity on which semantic info -- actually appears. if Unit_Kind in N_Generic_Declaration then E_Name := Defining_Entity (U); -- Note: in the following test, Unit_Kind is the original Nkind, but in -- the case of an instantiation, semantic analysis above will have -- replaced the unit by its instantiated version. If the instance body -- has been generated, the instance now denotes the body entity. For -- visibility purposes we need the entity of its spec. elsif (Unit_Kind = N_Package_Instantiation or else Nkind (Original_Node (Unit (Library_Unit (N)))) = N_Package_Instantiation) and then Nkind (U) = N_Package_Body then E_Name := Corresponding_Spec (U); elsif Unit_Kind = N_Package_Instantiation and then Nkind (U) = N_Package_Instantiation and then Present (Instance_Spec (U)) then -- If the instance has not been rewritten as a package declaration, -- then it appeared already in a previous with clause. Retrieve -- the entity from the previous instance. E_Name := Defining_Entity (Specification (Instance_Spec (U))); elsif Unit_Kind in N_Subprogram_Instantiation then -- The visible subprogram is created during instantiation, and is -- an attribute of the wrapper package. We retrieve the wrapper -- package directly from the instantiation node. If the instance -- is inlined the unit is still an instantiation. Otherwise it has -- been rewritten as the declaration of the wrapper itself. if Nkind (U) in N_Subprogram_Instantiation then E_Name := Related_Instance (Defining_Entity (Specification (Instance_Spec (U)))); else E_Name := Related_Instance (Defining_Entity (U)); end if; elsif Unit_Kind = N_Package_Renaming_Declaration or else Unit_Kind in N_Generic_Renaming_Declaration then E_Name := Defining_Entity (U); elsif Unit_Kind = N_Subprogram_Body and then Nkind (Name (N)) = N_Selected_Component and then not Acts_As_Spec (Library_Unit (N)) then -- For a child unit that has no spec, one has been created and -- analyzed. The entity required is that of the spec. E_Name := Corresponding_Spec (U); else E_Name := Defining_Entity (U); end if; if Nkind (Name (N)) = N_Selected_Component then -- Child unit in a with clause Change_Selected_Component_To_Expanded_Name (Name (N)); -- If this is a child unit without a spec, and it has been analyzed -- already, a declaration has been created for it. The with_clause -- must reflect the actual body, and not the generated declaration, -- to prevent spurious binding errors involving an out-of-date spec. -- Note that this can only happen if the unit includes more than one -- with_clause for the child unit (e.g. in separate subunits). if Unit_Kind = N_Subprogram_Declaration and then Analyzed (Library_Unit (N)) and then not Comes_From_Source (Library_Unit (N)) then Set_Library_Unit (N, Cunit (Get_Source_Unit (Corresponding_Body (U)))); end if; end if; -- Restore style checks Style_Check := Save_Style_Check; -- Record the reference, but do NOT set the unit as referenced, we want -- to consider the unit as unreferenced if this is the only reference -- that occurs. Set_Entity_With_Style_Check (Name (N), E_Name); Generate_Reference (E_Name, Name (N), 'w', Set_Ref => False); -- Generate references and check No_Dependence restriction for parents if Is_Child_Unit (E_Name) then Pref := Prefix (Name (N)); Par_Name := Scope (E_Name); while Nkind (Pref) = N_Selected_Component loop Change_Selected_Component_To_Expanded_Name (Pref); if Present (Entity (Selector_Name (Pref))) and then Present (Renamed_Entity (Entity (Selector_Name (Pref)))) and then Entity (Selector_Name (Pref)) /= Par_Name then -- The prefix is a child unit that denotes a renaming declaration. -- Replace the prefix directly with the renamed unit, because the -- rest of the prefix is irrelevant to the visibility of the real -- unit. Rewrite (Pref, New_Occurrence_Of (Par_Name, Sloc (Pref))); exit; end if; Set_Entity_With_Style_Check (Pref, Par_Name); Generate_Reference (Par_Name, Pref); Check_Restriction_No_Dependence (Pref, N); Pref := Prefix (Pref); -- If E_Name is the dummy entity for a nonexistent unit, its scope -- is set to Standard_Standard, and no attempt should be made to -- further unwind scopes. if Par_Name /= Standard_Standard then Par_Name := Scope (Par_Name); end if; -- Abandon processing in case of previous errors if No (Par_Name) then pragma Assert (Serious_Errors_Detected /= 0); return; end if; end loop; if Present (Entity (Pref)) and then not Analyzed (Parent (Parent (Entity (Pref)))) then -- If the entity is set without its unit being compiled, the -- original parent is a renaming, and Par_Name is the renamed -- entity. For visibility purposes, we need the original entity, -- which must be analyzed now because Load_Unit directly retrieves -- the renamed unit, and the renaming declaration itself has not -- been analyzed. Analyze (Parent (Parent (Entity (Pref)))); pragma Assert (Renamed_Object (Entity (Pref)) = Par_Name); Par_Name := Entity (Pref); end if; -- Guard against missing or misspelled child units if Present (Par_Name) then Set_Entity_With_Style_Check (Pref, Par_Name); Generate_Reference (Par_Name, Pref); else pragma Assert (Serious_Errors_Detected /= 0); -- Mark the node to indicate that a related error has been posted. -- This defends further compilation passes against improper use of -- the invalid WITH clause node. Set_Error_Posted (N); Set_Name (N, Error); return; end if; end if; -- If the withed unit is System, and a system extension pragma is -- present, compile the extension now, rather than waiting for a -- visibility check on a specific entity. if Chars (E_Name) = Name_System and then Scope (E_Name) = Standard_Standard and then Present (System_Extend_Unit) and then Present_System_Aux (N) then -- If the extension is not present, an error will have been emitted null; end if; -- Ada 2005 (AI-262): Remove from visibility the entity corresponding -- to private_with units; they will be made visible later (just before -- the private part is analyzed) if Private_Present (N) then Set_Is_Immediately_Visible (E_Name, False); end if; end Analyze_With_Clause; ------------------------------ -- Check_Private_Child_Unit -- ------------------------------ procedure Check_Private_Child_Unit (N : Node_Id) is Lib_Unit : constant Node_Id := Unit (N); Item : Node_Id; Curr_Unit : Entity_Id; Sub_Parent : Node_Id; Priv_Child : Entity_Id; Par_Lib : Entity_Id; Par_Spec : Node_Id; function Is_Private_Library_Unit (Unit : Entity_Id) return Boolean; -- Returns true if and only if the library unit is declared with -- an explicit designation of private. ----------------------------- -- Is_Private_Library_Unit -- ----------------------------- function Is_Private_Library_Unit (Unit : Entity_Id) return Boolean is Comp_Unit : constant Node_Id := Parent (Unit_Declaration_Node (Unit)); begin return Private_Present (Comp_Unit); end Is_Private_Library_Unit; -- Start of processing for Check_Private_Child_Unit begin if Nkind_In (Lib_Unit, N_Package_Body, N_Subprogram_Body) then Curr_Unit := Defining_Entity (Unit (Library_Unit (N))); Par_Lib := Curr_Unit; elsif Nkind (Lib_Unit) = N_Subunit then -- The parent is itself a body. The parent entity is to be found in -- the corresponding spec. Sub_Parent := Library_Unit (N); Curr_Unit := Defining_Entity (Unit (Library_Unit (Sub_Parent))); -- If the parent itself is a subunit, Curr_Unit is the entity of the -- enclosing body, retrieve the spec entity which is the proper -- ancestor we need for the following tests. if Ekind (Curr_Unit) = E_Package_Body then Curr_Unit := Spec_Entity (Curr_Unit); end if; Par_Lib := Curr_Unit; else Curr_Unit := Defining_Entity (Lib_Unit); Par_Lib := Curr_Unit; Par_Spec := Parent_Spec (Lib_Unit); if No (Par_Spec) then Par_Lib := Empty; else Par_Lib := Defining_Entity (Unit (Par_Spec)); end if; end if; -- Loop through context items Item := First (Context_Items (N)); while Present (Item) loop -- Ada 2005 (AI-262): Allow private_with of a private child package -- in public siblings if Nkind (Item) = N_With_Clause and then not Implicit_With (Item) and then not Limited_Present (Item) and then Is_Private_Descendant (Entity (Name (Item))) then Priv_Child := Entity (Name (Item)); declare Curr_Parent : Entity_Id := Par_Lib; Child_Parent : Entity_Id := Scope (Priv_Child); Prv_Ancestor : Entity_Id := Child_Parent; Curr_Private : Boolean := Is_Private_Library_Unit (Curr_Unit); begin -- If the child unit is a public child then locate the nearest -- private ancestor. Child_Parent will then be set to the -- parent of that ancestor. if not Is_Private_Library_Unit (Priv_Child) then while Present (Prv_Ancestor) and then not Is_Private_Library_Unit (Prv_Ancestor) loop Prv_Ancestor := Scope (Prv_Ancestor); end loop; if Present (Prv_Ancestor) then Child_Parent := Scope (Prv_Ancestor); end if; end if; while Present (Curr_Parent) and then Curr_Parent /= Standard_Standard and then Curr_Parent /= Child_Parent loop Curr_Private := Curr_Private or else Is_Private_Library_Unit (Curr_Parent); Curr_Parent := Scope (Curr_Parent); end loop; if No (Curr_Parent) then Curr_Parent := Standard_Standard; end if; if Curr_Parent /= Child_Parent then if Ekind (Priv_Child) = E_Generic_Package and then Chars (Priv_Child) in Text_IO_Package_Name and then Chars (Scope (Scope (Priv_Child))) = Name_Ada then Error_Msg_NE ("& is a nested package, not a compilation unit", Name (Item), Priv_Child); else Error_Msg_N ("unit in with clause is private child unit!", Item); Error_Msg_NE ("\current unit must also have parent&!", Item, Child_Parent); end if; elsif Curr_Private or else Private_Present (Item) or else Nkind_In (Lib_Unit, N_Package_Body, N_Subunit) or else (Nkind (Lib_Unit) = N_Subprogram_Body and then not Acts_As_Spec (Parent (Lib_Unit))) then null; else Error_Msg_NE ("current unit must also be private descendant of&", Item, Child_Parent); end if; end; end if; Next (Item); end loop; end Check_Private_Child_Unit; ---------------------- -- Check_Stub_Level -- ---------------------- procedure Check_Stub_Level (N : Node_Id) is Par : constant Node_Id := Parent (N); Kind : constant Node_Kind := Nkind (Par); begin if Nkind_In (Kind, N_Package_Body, N_Subprogram_Body, N_Task_Body, N_Protected_Body) and then Nkind_In (Parent (Par), N_Compilation_Unit, N_Subunit) then null; -- In an instance, a missing stub appears at any level. A warning -- message will have been emitted already for the missing file. elsif not In_Instance then Error_Msg_N ("stub cannot appear in an inner scope", N); elsif Expander_Active then Error_Msg_N ("missing proper body", N); end if; end Check_Stub_Level; ------------------------ -- Expand_With_Clause -- ------------------------ procedure Expand_With_Clause (Item : Node_Id; Nam : Node_Id; N : Node_Id) is Loc : constant Source_Ptr := Sloc (Nam); Ent : constant Entity_Id := Entity (Nam); Withn : Node_Id; P : Node_Id; function Build_Unit_Name (Nam : Node_Id) return Node_Id; -- Build name to be used in implicit with_clause. In most cases this -- is the source name, but if renamings are present we must make the -- original unit visible, not the one it renames. The entity in the -- with clause is the renamed unit, but the identifier is the one from -- the source, which allows us to recover the unit renaming. --------------------- -- Build_Unit_Name -- --------------------- function Build_Unit_Name (Nam : Node_Id) return Node_Id is Ent : Entity_Id; Result : Node_Id; begin if Nkind (Nam) = N_Identifier then return New_Occurrence_Of (Entity (Nam), Loc); else Ent := Entity (Nam); if Present (Entity (Selector_Name (Nam))) and then Chars (Entity (Selector_Name (Nam))) /= Chars (Ent) and then Nkind (Unit_Declaration_Node (Entity (Selector_Name (Nam)))) = N_Package_Renaming_Declaration then -- The name in the with_clause is of the form A.B.C, and B is -- given by a renaming declaration. In that case we may not -- have analyzed the unit for B, but replaced it directly in -- lib-load with the unit it renames. We have to make A.B -- visible, so analyze the declaration for B now, in case it -- has not been done yet. Ent := Entity (Selector_Name (Nam)); Analyze (Parent (Unit_Declaration_Node (Entity (Selector_Name (Nam))))); end if; Result := Make_Expanded_Name (Loc, Chars => Chars (Entity (Nam)), Prefix => Build_Unit_Name (Prefix (Nam)), Selector_Name => New_Occurrence_Of (Ent, Loc)); Set_Entity (Result, Ent); return Result; end if; end Build_Unit_Name; -- Start of processing for Expand_With_Clause begin New_Nodes_OK := New_Nodes_OK + 1; Withn := Make_With_Clause (Loc, Name => Build_Unit_Name (Nam)); P := Parent (Unit_Declaration_Node (Ent)); Set_Library_Unit (Withn, P); Set_Corresponding_Spec (Withn, Ent); Set_First_Name (Withn, True); Set_Implicit_With (Withn, True); -- If the unit is a package declaration, a private_with_clause on a -- child unit implies the implicit with on the parent is also private. if Nkind (Unit (N)) = N_Package_Declaration then Set_Private_Present (Withn, Private_Present (Item)); end if; Prepend (Withn, Context_Items (N)); Mark_Rewrite_Insertion (Withn); Install_Withed_Unit (Withn); if Nkind (Nam) = N_Expanded_Name then Expand_With_Clause (Item, Prefix (Nam), N); end if; New_Nodes_OK := New_Nodes_OK - 1; end Expand_With_Clause; ----------------------- -- Get_Parent_Entity -- ----------------------- function Get_Parent_Entity (Unit : Node_Id) return Entity_Id is begin if Nkind (Unit) = N_Package_Body and then Nkind (Original_Node (Unit)) = N_Package_Instantiation then return Defining_Entity (Specification (Instance_Spec (Original_Node (Unit)))); elsif Nkind (Unit) = N_Package_Instantiation then return Defining_Entity (Specification (Instance_Spec (Unit))); else return Defining_Entity (Unit); end if; end Get_Parent_Entity; --------------------- -- Has_With_Clause -- --------------------- function Has_With_Clause (C_Unit : Node_Id; Pack : Entity_Id; Is_Limited : Boolean := False) return Boolean is Item : Node_Id; function Named_Unit (Clause : Node_Id) return Entity_Id; -- Return the entity for the unit named in a [limited] with clause ---------------- -- Named_Unit -- ---------------- function Named_Unit (Clause : Node_Id) return Entity_Id is begin if Nkind (Name (Clause)) = N_Selected_Component then return Entity (Selector_Name (Name (Clause))); else return Entity (Name (Clause)); end if; end Named_Unit; -- Start of processing for Has_With_Clause begin if Present (Context_Items (C_Unit)) then Item := First (Context_Items (C_Unit)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Limited_Present (Item) = Is_Limited and then Named_Unit (Item) = Pack then return True; end if; Next (Item); end loop; end if; return False; end Has_With_Clause; ----------------------------- -- Implicit_With_On_Parent -- ----------------------------- procedure Implicit_With_On_Parent (Child_Unit : Node_Id; N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); P : constant Node_Id := Parent_Spec (Child_Unit); P_Unit : Node_Id := Unit (P); P_Name : constant Entity_Id := Get_Parent_Entity (P_Unit); Withn : Node_Id; function Build_Ancestor_Name (P : Node_Id) return Node_Id; -- Build prefix of child unit name. Recurse if needed function Build_Unit_Name return Node_Id; -- If the unit is a child unit, build qualified name with all ancestors ------------------------- -- Build_Ancestor_Name -- ------------------------- function Build_Ancestor_Name (P : Node_Id) return Node_Id is P_Ref : constant Node_Id := New_Reference_To (Defining_Entity (P), Loc); P_Spec : Node_Id := P; begin -- Ancestor may have been rewritten as a package body. Retrieve -- the original spec to trace earlier ancestors. if Nkind (P) = N_Package_Body and then Nkind (Original_Node (P)) = N_Package_Instantiation then P_Spec := Original_Node (P); end if; if No (Parent_Spec (P_Spec)) then return P_Ref; else return Make_Selected_Component (Loc, Prefix => Build_Ancestor_Name (Unit (Parent_Spec (P_Spec))), Selector_Name => P_Ref); end if; end Build_Ancestor_Name; --------------------- -- Build_Unit_Name -- --------------------- function Build_Unit_Name return Node_Id is Result : Node_Id; begin if No (Parent_Spec (P_Unit)) then return New_Reference_To (P_Name, Loc); else Result := Make_Expanded_Name (Loc, Chars => Chars (P_Name), Prefix => Build_Ancestor_Name (Unit (Parent_Spec (P_Unit))), Selector_Name => New_Reference_To (P_Name, Loc)); Set_Entity (Result, P_Name); return Result; end if; end Build_Unit_Name; -- Start of processing for Implicit_With_On_Parent begin -- The unit of the current compilation may be a package body that -- replaces an instance node. In this case we need the original instance -- node to construct the proper parent name. if Nkind (P_Unit) = N_Package_Body and then Nkind (Original_Node (P_Unit)) = N_Package_Instantiation then P_Unit := Original_Node (P_Unit); end if; -- We add the implicit with if the child unit is the current unit being -- compiled. If the current unit is a body, we do not want to add an -- implicit_with a second time to the corresponding spec. if Nkind (Child_Unit) = N_Package_Declaration and then Child_Unit /= Unit (Cunit (Current_Sem_Unit)) then return; end if; New_Nodes_OK := New_Nodes_OK + 1; Withn := Make_With_Clause (Loc, Name => Build_Unit_Name); Set_Library_Unit (Withn, P); Set_Corresponding_Spec (Withn, P_Name); Set_First_Name (Withn, True); Set_Implicit_With (Withn, True); -- Node is placed at the beginning of the context items, so that -- subsequent use clauses on the parent can be validated. Prepend (Withn, Context_Items (N)); Mark_Rewrite_Insertion (Withn); Install_Withed_Unit (Withn); if Is_Child_Spec (P_Unit) then Implicit_With_On_Parent (P_Unit, N); end if; New_Nodes_OK := New_Nodes_OK - 1; end Implicit_With_On_Parent; -------------- -- In_Chain -- -------------- function In_Chain (E : Entity_Id) return Boolean is H : Entity_Id; begin H := Current_Entity (E); while Present (H) loop if H = E then return True; else H := Homonym (H); end if; end loop; return False; end In_Chain; --------------------- -- Install_Context -- --------------------- procedure Install_Context (N : Node_Id) is Lib_Unit : constant Node_Id := Unit (N); begin Install_Context_Clauses (N); if Is_Child_Spec (Lib_Unit) then Install_Parents (Lib_Unit, Private_Present (Parent (Lib_Unit))); end if; Install_Limited_Context_Clauses (N); end Install_Context; ----------------------------- -- Install_Context_Clauses -- ----------------------------- procedure Install_Context_Clauses (N : Node_Id) is Lib_Unit : constant Node_Id := Unit (N); Item : Node_Id; Uname_Node : Entity_Id; Check_Private : Boolean := False; Decl_Node : Node_Id; Lib_Parent : Entity_Id; begin -- First skip configuration pragmas at the start of the context. They -- are not technically part of the context clause, but that's where the -- parser puts them. Note they were analyzed in Analyze_Context. Item := First (Context_Items (N)); while Present (Item) and then Nkind (Item) = N_Pragma and then Pragma_Name (Item) in Configuration_Pragma_Names loop Next (Item); end loop; -- Loop through the actual context clause items. We process everything -- except Limited_With clauses in this routine. Limited_With clauses -- are separately installed (see Install_Limited_Context_Clauses). while Present (Item) loop -- Case of explicit WITH clause if Nkind (Item) = N_With_Clause and then not Implicit_With (Item) then if Limited_Present (Item) then -- Limited withed units will be installed later goto Continue; -- If Name (Item) is not an entity name, something is wrong, and -- this will be detected in due course, for now ignore the item elsif not Is_Entity_Name (Name (Item)) then goto Continue; elsif No (Entity (Name (Item))) then Set_Entity (Name (Item), Any_Id); goto Continue; end if; Uname_Node := Entity (Name (Item)); if Is_Private_Descendant (Uname_Node) then Check_Private := True; end if; Install_Withed_Unit (Item); Decl_Node := Unit_Declaration_Node (Uname_Node); -- If the unit is a subprogram instance, it appears nested within -- a package that carries the parent information. if Is_Generic_Instance (Uname_Node) and then Ekind (Uname_Node) /= E_Package then Decl_Node := Parent (Parent (Decl_Node)); end if; if Is_Child_Spec (Decl_Node) then if Nkind (Name (Item)) = N_Expanded_Name then Expand_With_Clause (Item, Prefix (Name (Item)), N); else -- If not an expanded name, the child unit must be a -- renaming, nothing to do. null; end if; elsif Nkind (Decl_Node) = N_Subprogram_Body and then not Acts_As_Spec (Parent (Decl_Node)) and then Is_Child_Spec (Unit (Library_Unit (Parent (Decl_Node)))) then Implicit_With_On_Parent (Unit (Library_Unit (Parent (Decl_Node))), N); end if; -- Check license conditions unless this is a dummy unit if Sloc (Library_Unit (Item)) /= No_Location then License_Check : declare Withu : constant Unit_Number_Type := Get_Source_Unit (Library_Unit (Item)); Withl : constant License_Type := License (Source_Index (Withu)); Unitl : constant License_Type := License (Source_Index (Current_Sem_Unit)); procedure License_Error; -- Signal error of bad license ------------------- -- License_Error -- ------------------- procedure License_Error is begin Error_Msg_N ("?license of withed unit & may be inconsistent", Name (Item)); end License_Error; -- Start of processing for License_Check begin -- Exclude license check if withed unit is an internal unit. -- This situation arises e.g. with the GPL version of GNAT. if Is_Internal_File_Name (Unit_File_Name (Withu)) then null; -- Otherwise check various cases else case Unitl is when Unknown => null; when Restricted => if Withl = GPL then License_Error; end if; when GPL => if Withl = Restricted then License_Error; end if; when Modified_GPL => if Withl = Restricted or else Withl = GPL then License_Error; end if; when Unrestricted => null; end case; end if; end License_Check; end if; -- Case of USE PACKAGE clause elsif Nkind (Item) = N_Use_Package_Clause then Analyze_Use_Package (Item); -- Case of USE TYPE clause elsif Nkind (Item) = N_Use_Type_Clause then Analyze_Use_Type (Item); -- case of PRAGMA elsif Nkind (Item) = N_Pragma then Analyze (Item); end if; <<Continue>> Next (Item); end loop; if Is_Child_Spec (Lib_Unit) then -- The unit also has implicit with_clauses on its own parents if No (Context_Items (N)) then Set_Context_Items (N, New_List); end if; Implicit_With_On_Parent (Lib_Unit, N); end if; -- If the unit is a body, the context of the specification must also -- be installed. That includes private with_clauses in that context. if Nkind (Lib_Unit) = N_Package_Body or else (Nkind (Lib_Unit) = N_Subprogram_Body and then not Acts_As_Spec (N)) then Install_Context (Library_Unit (N)); -- Only install private with-clauses of a spec that comes from -- source, excluding specs created for a subprogram body that is -- a child unit. if Comes_From_Source (Library_Unit (N)) then Install_Private_With_Clauses (Defining_Entity (Unit (Library_Unit (N)))); end if; if Is_Child_Spec (Unit (Library_Unit (N))) then -- If the unit is the body of a public child unit, the private -- declarations of the parent must be made visible. If the child -- unit is private, the private declarations have been installed -- already in the call to Install_Parents for the spec. Installing -- private declarations must be done for all ancestors of public -- child units. In addition, sibling units mentioned in the -- context clause of the body are directly visible. declare Lib_Spec : Node_Id; P : Node_Id; P_Name : Entity_Id; begin Lib_Spec := Unit (Library_Unit (N)); while Is_Child_Spec (Lib_Spec) loop P := Unit (Parent_Spec (Lib_Spec)); P_Name := Defining_Entity (P); if not (Private_Present (Parent (Lib_Spec))) and then not In_Private_Part (P_Name) then Install_Private_Declarations (P_Name); Install_Private_With_Clauses (P_Name); Set_Use (Private_Declarations (Specification (P))); end if; Lib_Spec := P; end loop; end; end if; -- For a package body, children in context are immediately visible Install_Siblings (Defining_Entity (Unit (Library_Unit (N))), N); end if; if Nkind_In (Lib_Unit, N_Generic_Package_Declaration, N_Generic_Subprogram_Declaration, N_Package_Declaration, N_Subprogram_Declaration) then if Is_Child_Spec (Lib_Unit) then Lib_Parent := Defining_Entity (Unit (Parent_Spec (Lib_Unit))); Set_Is_Private_Descendant (Defining_Entity (Lib_Unit), Is_Private_Descendant (Lib_Parent) or else Private_Present (Parent (Lib_Unit))); else Set_Is_Private_Descendant (Defining_Entity (Lib_Unit), Private_Present (Parent (Lib_Unit))); end if; end if; if Check_Private then Check_Private_Child_Unit (N); end if; end Install_Context_Clauses; ------------------------------------- -- Install_Limited_Context_Clauses -- ------------------------------------- procedure Install_Limited_Context_Clauses (N : Node_Id) is Item : Node_Id; procedure Check_Renamings (P : Node_Id; W : Node_Id); -- Check that the unlimited view of a given compilation_unit is not -- already visible through "use + renamings". procedure Check_Private_Limited_Withed_Unit (Item : Node_Id); -- Check that if a limited_with clause of a given compilation_unit -- mentions a descendant of a private child of some library unit, then -- the given compilation_unit shall be the declaration of a private -- descendant of that library unit, or a public descendant of such. The -- code is analogous to that of Check_Private_Child_Unit but we cannot -- use entities on the limited with_clauses because their units have not -- been analyzed, so we have to climb the tree of ancestors looking for -- private keywords. procedure Expand_Limited_With_Clause (Comp_Unit : Node_Id; Nam : Node_Id; N : Node_Id); -- If a child unit appears in a limited_with clause, there are implicit -- limited_with clauses on all parents that are not already visible -- through a regular with clause. This procedure creates the implicit -- limited with_clauses for the parents and loads the corresponding -- units. The shadow entities are created when the inserted clause is -- analyzed. Implements Ada 2005 (AI-50217). function Is_Ancestor_Unit (U1 : Node_Id; U2 : Node_Id) return Boolean; -- When compiling a unit Q descended from some parent unit P, a limited -- with_clause in the context of P that names some other ancestor of Q -- must not be installed because the ancestor is immediately visible. --------------------- -- Check_Renamings -- --------------------- procedure Check_Renamings (P : Node_Id; W : Node_Id) is Item : Node_Id; Spec : Node_Id; WEnt : Entity_Id; Nam : Node_Id; E : Entity_Id; E2 : Entity_Id; begin pragma Assert (Nkind (W) = N_With_Clause); -- Protect the frontend against previous critical errors case Nkind (Unit (Library_Unit (W))) is when N_Subprogram_Declaration | N_Package_Declaration | N_Generic_Subprogram_Declaration | N_Generic_Package_Declaration => null; when others => return; end case; -- Check "use + renamings" WEnt := Defining_Unit_Name (Specification (Unit (Library_Unit (W)))); Spec := Specification (Unit (P)); Item := First (Visible_Declarations (Spec)); while Present (Item) loop -- Look only at use package clauses if Nkind (Item) = N_Use_Package_Clause then -- Traverse the list of packages Nam := First (Names (Item)); while Present (Nam) loop E := Entity (Nam); pragma Assert (Present (Parent (E))); if Nkind (Parent (E)) = N_Package_Renaming_Declaration and then Renamed_Entity (E) = WEnt then -- The unlimited view is visible through use clause and -- renamings. There is no need to generate the error -- message here because Is_Visible_Through_Renamings -- takes care of generating the precise error message. return; elsif Nkind (Parent (E)) = N_Package_Specification then -- The use clause may refer to a local package. -- Check all the enclosing scopes. E2 := E; while E2 /= Standard_Standard and then E2 /= WEnt loop E2 := Scope (E2); end loop; if E2 = WEnt then Error_Msg_N ("unlimited view visible through use clause ", W); return; end if; end if; Next (Nam); end loop; end if; Next (Item); end loop; -- Recursive call to check all the ancestors if Is_Child_Spec (Unit (P)) then Check_Renamings (P => Parent_Spec (Unit (P)), W => W); end if; end Check_Renamings; --------------------------------------- -- Check_Private_Limited_Withed_Unit -- --------------------------------------- procedure Check_Private_Limited_Withed_Unit (Item : Node_Id) is Curr_Parent : Node_Id; Child_Parent : Node_Id; Curr_Private : Boolean; begin -- Compilation unit of the parent of the withed library unit Child_Parent := Library_Unit (Item); -- If the child unit is a public child, then locate its nearest -- private ancestor, if any, then Child_Parent will then be set to -- the parent of that ancestor. if not Private_Present (Library_Unit (Item)) then while Present (Child_Parent) and then not Private_Present (Child_Parent) loop Child_Parent := Parent_Spec (Unit (Child_Parent)); end loop; if No (Child_Parent) then return; end if; end if; Child_Parent := Parent_Spec (Unit (Child_Parent)); -- Traverse all the ancestors of the current compilation unit to -- check if it is a descendant of named library unit. Curr_Parent := Parent (Item); Curr_Private := Private_Present (Curr_Parent); while Present (Parent_Spec (Unit (Curr_Parent))) and then Curr_Parent /= Child_Parent loop Curr_Parent := Parent_Spec (Unit (Curr_Parent)); Curr_Private := Curr_Private or else Private_Present (Curr_Parent); end loop; if Curr_Parent /= Child_Parent then Error_Msg_N ("unit in with clause is private child unit!", Item); Error_Msg_NE ("\current unit must also have parent&!", Item, Defining_Unit_Name (Specification (Unit (Child_Parent)))); elsif Private_Present (Parent (Item)) or else Curr_Private or else Private_Present (Item) or else Nkind_In (Unit (Parent (Item)), N_Package_Body, N_Subprogram_Body, N_Subunit) then -- Current unit is private, of descendant of a private unit null; else Error_Msg_NE ("current unit must also be private descendant of&", Item, Defining_Unit_Name (Specification (Unit (Child_Parent)))); end if; end Check_Private_Limited_Withed_Unit; -------------------------------- -- Expand_Limited_With_Clause -- -------------------------------- procedure Expand_Limited_With_Clause (Comp_Unit : Node_Id; Nam : Node_Id; N : Node_Id) is Loc : constant Source_Ptr := Sloc (Nam); Unum : Unit_Number_Type; Withn : Node_Id; function Previous_Withed_Unit (W : Node_Id) return Boolean; -- Returns true if the context already includes a with_clause for -- this unit. If the with_clause is non-limited, the unit is fully -- visible and an implicit limited_with should not be created. If -- there is already a limited_with clause for W, a second one is -- simply redundant. -------------------------- -- Previous_Withed_Unit -- -------------------------- function Previous_Withed_Unit (W : Node_Id) return Boolean is Item : Node_Id; begin -- A limited with_clause cannot appear in the same context_clause -- as a nonlimited with_clause which mentions the same library. Item := First (Context_Items (Comp_Unit)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Library_Unit (Item) = Library_Unit (W) then return True; end if; Next (Item); end loop; return False; end Previous_Withed_Unit; -- Start of processing for Expand_Limited_With_Clause begin New_Nodes_OK := New_Nodes_OK + 1; if Nkind (Nam) = N_Identifier then -- Create node for name of withed unit Withn := Make_With_Clause (Loc, Name => New_Copy (Nam)); else pragma Assert (Nkind (Nam) = N_Selected_Component); Withn := Make_With_Clause (Loc, Name => Make_Selected_Component (Loc, Prefix => New_Copy_Tree (Prefix (Nam)), Selector_Name => New_Copy (Selector_Name (Nam)))); Set_Parent (Withn, Parent (N)); end if; Set_Limited_Present (Withn); Set_First_Name (Withn); Set_Implicit_With (Withn); Unum := Load_Unit (Load_Name => Get_Spec_Name (Get_Unit_Name (Nam)), Required => True, Subunit => False, Error_Node => Nam); -- Do not generate a limited_with_clause on the current unit. This -- path is taken when a unit has a limited_with clause on one of its -- child units. if Unum = Current_Sem_Unit then return; end if; Set_Library_Unit (Withn, Cunit (Unum)); Set_Corresponding_Spec (Withn, Specification (Unit (Cunit (Unum)))); if not Previous_Withed_Unit (Withn) then Prepend (Withn, Context_Items (Parent (N))); Mark_Rewrite_Insertion (Withn); -- Add implicit limited_with_clauses for parents of child units -- mentioned in limited_with clauses. if Nkind (Nam) = N_Selected_Component then Expand_Limited_With_Clause (Comp_Unit, Prefix (Nam), N); end if; Analyze (Withn); if not Limited_View_Installed (Withn) then Install_Limited_Withed_Unit (Withn); end if; end if; New_Nodes_OK := New_Nodes_OK - 1; end Expand_Limited_With_Clause; ---------------------- -- Is_Ancestor_Unit -- ---------------------- function Is_Ancestor_Unit (U1 : Node_Id; U2 : Node_Id) return Boolean is E1 : constant Entity_Id := Defining_Entity (Unit (U1)); E2 : Entity_Id; begin if Nkind_In (Unit (U2), N_Package_Body, N_Subprogram_Body) then E2 := Defining_Entity (Unit (Library_Unit (U2))); return Is_Ancestor_Package (E1, E2); else return False; end if; end Is_Ancestor_Unit; -- Start of processing for Install_Limited_Context_Clauses begin Item := First (Context_Items (N)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Limited_Present (Item) and then not Error_Posted (Item) then if Nkind (Name (Item)) = N_Selected_Component then Expand_Limited_With_Clause (Comp_Unit => N, Nam => Prefix (Name (Item)), N => Item); end if; Check_Private_Limited_Withed_Unit (Item); if not Implicit_With (Item) and then Is_Child_Spec (Unit (N)) then Check_Renamings (Parent_Spec (Unit (N)), Item); end if; -- A unit may have a limited with on itself if it has a limited -- with_clause on one of its child units. In that case it is -- already being compiled and it makes no sense to install its -- limited view. -- If the item is a limited_private_with_clause, install it if the -- current unit is a body or if it is a private child. Otherwise -- the private clause is installed before analyzing the private -- part of the current unit. if Library_Unit (Item) /= Cunit (Current_Sem_Unit) and then not Limited_View_Installed (Item) and then not Is_Ancestor_Unit (Library_Unit (Item), Cunit (Current_Sem_Unit)) then if not Private_Present (Item) or else Private_Present (N) or else Nkind_In (Unit (N), N_Package_Body, N_Subprogram_Body, N_Subunit) then Install_Limited_Withed_Unit (Item); end if; end if; end if; Next (Item); end loop; -- Ada 2005 (AI-412): Examine visible declarations of a package spec, -- looking for incomplete subtype declarations of incomplete types -- visible through a limited with clause. if Ada_Version >= Ada_2005 and then Analyzed (N) and then Nkind (Unit (N)) = N_Package_Declaration then declare Decl : Node_Id; Def_Id : Entity_Id; Non_Lim_View : Entity_Id; begin Decl := First (Visible_Declarations (Specification (Unit (N)))); while Present (Decl) loop if Nkind (Decl) = N_Subtype_Declaration and then Ekind (Defining_Identifier (Decl)) = E_Incomplete_Subtype and then From_With_Type (Defining_Identifier (Decl)) then Def_Id := Defining_Identifier (Decl); Non_Lim_View := Non_Limited_View (Def_Id); if not Is_Incomplete_Type (Non_Lim_View) then -- Convert an incomplete subtype declaration into a -- corresponding non-limited view subtype declaration. -- This is usually the case when analyzing a body that -- has regular with clauses, when the spec has limited -- ones. -- If the non-limited view is still incomplete, it is -- the dummy entry already created, and the declaration -- cannot be reanalyzed. This is the case when installing -- a parent unit that has limited with-clauses. Set_Subtype_Indication (Decl, New_Reference_To (Non_Lim_View, Sloc (Def_Id))); Set_Etype (Def_Id, Non_Lim_View); Set_Ekind (Def_Id, Subtype_Kind (Ekind (Non_Lim_View))); Set_Analyzed (Decl, False); -- Reanalyze the declaration, suppressing the call to -- Enter_Name to avoid duplicate names. Analyze_Subtype_Declaration (N => Decl, Skip => True); end if; end if; Next (Decl); end loop; end; end if; end Install_Limited_Context_Clauses; --------------------- -- Install_Parents -- --------------------- procedure Install_Parents (Lib_Unit : Node_Id; Is_Private : Boolean) is P : Node_Id; E_Name : Entity_Id; P_Name : Entity_Id; P_Spec : Node_Id; begin P := Unit (Parent_Spec (Lib_Unit)); P_Name := Get_Parent_Entity (P); if Etype (P_Name) = Any_Type then return; end if; if Ekind (P_Name) = E_Generic_Package and then not Nkind_In (Lib_Unit, N_Generic_Subprogram_Declaration, N_Generic_Package_Declaration) and then Nkind (Lib_Unit) not in N_Generic_Renaming_Declaration then Error_Msg_N ("child of a generic package must be a generic unit", Lib_Unit); elsif not Is_Package_Or_Generic_Package (P_Name) then Error_Msg_N ("parent unit must be package or generic package", Lib_Unit); raise Unrecoverable_Error; elsif Present (Renamed_Object (P_Name)) then Error_Msg_N ("parent unit cannot be a renaming", Lib_Unit); raise Unrecoverable_Error; -- Verify that a child of an instance is itself an instance, or the -- renaming of one. Given that an instance that is a unit is replaced -- with a package declaration, check against the original node. The -- parent may be currently being instantiated, in which case it appears -- as a declaration, but the generic_parent is already established -- indicating that we deal with an instance. elsif Nkind (Original_Node (P)) = N_Package_Instantiation then if Nkind (Lib_Unit) in N_Renaming_Declaration or else Nkind (Original_Node (Lib_Unit)) in N_Generic_Instantiation or else (Nkind (Lib_Unit) = N_Package_Declaration and then Present (Generic_Parent (Specification (Lib_Unit)))) then null; else Error_Msg_N ("child of an instance must be an instance or renaming", Lib_Unit); end if; end if; -- This is the recursive call that ensures all parents are loaded if Is_Child_Spec (P) then Install_Parents (P, Is_Private or else Private_Present (Parent (Lib_Unit))); end if; -- Now we can install the context for this parent Install_Context_Clauses (Parent_Spec (Lib_Unit)); Install_Limited_Context_Clauses (Parent_Spec (Lib_Unit)); Install_Siblings (P_Name, Parent (Lib_Unit)); -- The child unit is in the declarative region of the parent. The parent -- must therefore appear in the scope stack and be visible, as when -- compiling the corresponding body. If the child unit is private or it -- is a package body, private declarations must be accessible as well. -- Use declarations in the parent must also be installed. Finally, other -- child units of the same parent that are in the context are -- immediately visible. -- Find entity for compilation unit, and set its private descendant -- status as needed. Indicate that it is a compilation unit, which is -- redundant in general, but needed if this is a generated child spec -- for a child body without previous spec. E_Name := Defining_Entity (Lib_Unit); Set_Is_Child_Unit (E_Name); Set_Is_Compilation_Unit (E_Name); Set_Is_Private_Descendant (E_Name, Is_Private_Descendant (P_Name) or else Private_Present (Parent (Lib_Unit))); P_Spec := Specification (Unit_Declaration_Node (P_Name)); Push_Scope (P_Name); -- Save current visibility of unit Scope_Stack.Table (Scope_Stack.Last).Previous_Visibility := Is_Immediately_Visible (P_Name); Set_Is_Immediately_Visible (P_Name); Install_Visible_Declarations (P_Name); Set_Use (Visible_Declarations (P_Spec)); -- If the parent is a generic unit, its formal part may contain formal -- packages and use clauses for them. if Ekind (P_Name) = E_Generic_Package then Set_Use (Generic_Formal_Declarations (Parent (P_Spec))); end if; if Is_Private or else Private_Present (Parent (Lib_Unit)) then Install_Private_Declarations (P_Name); Install_Private_With_Clauses (P_Name); Set_Use (Private_Declarations (P_Spec)); end if; end Install_Parents; ---------------------------------- -- Install_Private_With_Clauses -- ---------------------------------- procedure Install_Private_With_Clauses (P : Entity_Id) is Decl : constant Node_Id := Unit_Declaration_Node (P); Item : Node_Id; begin if Debug_Flag_I then Write_Str ("install private with clauses of "); Write_Name (Chars (P)); Write_Eol; end if; if Nkind (Parent (Decl)) = N_Compilation_Unit then Item := First (Context_Items (Parent (Decl))); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Private_Present (Item) then if Limited_Present (Item) then if not Limited_View_Installed (Item) then Install_Limited_Withed_Unit (Item); end if; else Install_Withed_Unit (Item, Private_With_OK => True); end if; end if; Next (Item); end loop; end if; end Install_Private_With_Clauses; ---------------------- -- Install_Siblings -- ---------------------- procedure Install_Siblings (U_Name : Entity_Id; N : Node_Id) is Item : Node_Id; Id : Entity_Id; Prev : Entity_Id; begin -- Iterate over explicit with clauses, and check whether the scope of -- each entity is an ancestor of the current unit, in which case it is -- immediately visible. Item := First (Context_Items (N)); while Present (Item) loop -- Do not install private_with_clauses declaration, unless unit -- is itself a private child unit, or is a body. Note that for a -- subprogram body the private_with_clause does not take effect until -- after the specification. if Nkind (Item) /= N_With_Clause or else Implicit_With (Item) or else Limited_Present (Item) or else Error_Posted (Item) then null; elsif not Private_Present (Item) or else Private_Present (N) or else Nkind (Unit (N)) = N_Package_Body then Id := Entity (Name (Item)); if Is_Child_Unit (Id) and then Is_Ancestor_Package (Scope (Id), U_Name) then Set_Is_Immediately_Visible (Id); -- Check for the presence of another unit in the context that -- may be inadvertently hidden by the child. Prev := Current_Entity (Id); if Present (Prev) and then Is_Immediately_Visible (Prev) and then not Is_Child_Unit (Prev) then declare Clause : Node_Id; begin Clause := First (Context_Items (N)); while Present (Clause) loop if Nkind (Clause) = N_With_Clause and then Entity (Name (Clause)) = Prev then Error_Msg_NE ("child unit& hides compilation unit " & "with the same name?", Name (Item), Id); exit; end if; Next (Clause); end loop; end; end if; -- The With_Clause may be on a grand-child or one of its further -- descendants, which makes a child immediately visible. Examine -- ancestry to determine whether such a child exists. For example, -- if current unit is A.C, and with_clause is on A.X.Y.Z, then X -- is immediately visible. elsif Is_Child_Unit (Id) then declare Par : Entity_Id; begin Par := Scope (Id); while Is_Child_Unit (Par) loop if Is_Ancestor_Package (Scope (Par), U_Name) then Set_Is_Immediately_Visible (Par); exit; end if; Par := Scope (Par); end loop; end; end if; -- If the item is a private with-clause on a child unit, the parent -- may have been installed already, but the child unit must remain -- invisible until installed in a private part or body, unless there -- is already a regular with_clause for it in the current unit. elsif Private_Present (Item) then Id := Entity (Name (Item)); if Is_Child_Unit (Id) then declare Clause : Node_Id; function In_Context return Boolean; -- Scan context of current unit, to check whether there is -- a with_clause on the same unit as a private with-clause -- on a parent, in which case child unit is visible. If the -- unit is a grand-child, the same applies to its parent. ---------------- -- In_Context -- ---------------- function In_Context return Boolean is begin Clause := First (Context_Items (Cunit (Current_Sem_Unit))); while Present (Clause) loop if Nkind (Clause) = N_With_Clause and then Comes_From_Source (Clause) and then Is_Entity_Name (Name (Clause)) and then not Private_Present (Clause) then if Entity (Name (Clause)) = Id or else (Nkind (Name (Clause)) = N_Expanded_Name and then Entity (Prefix (Name (Clause))) = Id) then return True; end if; end if; Next (Clause); end loop; return False; end In_Context; begin Set_Is_Visible_Child_Unit (Id, In_Context); end; end if; end if; Next (Item); end loop; end Install_Siblings; --------------------------------- -- Install_Limited_Withed_Unit -- --------------------------------- procedure Install_Limited_Withed_Unit (N : Node_Id) is P_Unit : constant Entity_Id := Unit (Library_Unit (N)); E : Entity_Id; P : Entity_Id; Is_Child_Package : Boolean := False; Lim_Header : Entity_Id; Lim_Typ : Entity_Id; procedure Check_Body_Required; -- A unit mentioned in a limited with_clause may not be mentioned in -- a regular with_clause, but must still be included in the current -- partition. We need to determine whether the unit needs a body, so -- that the binder can determine the name of the file to be compiled. -- Checking whether a unit needs a body can be done without semantic -- analysis, by examining the nature of the declarations in the package. function Has_Limited_With_Clause (C_Unit : Entity_Id; Pack : Entity_Id) return Boolean; -- Determine whether any package in the ancestor chain starting with -- C_Unit has a limited with clause for package Pack. function Is_Visible_Through_Renamings (P : Entity_Id) return Boolean; -- Check if some package installed though normal with-clauses has a -- renaming declaration of package P. AARM 10.1.2(21/2). ------------------------- -- Check_Body_Required -- ------------------------- procedure Check_Body_Required is PA : constant List_Id := Pragmas_After (Aux_Decls_Node (Parent (P_Unit))); procedure Check_Declarations (Spec : Node_Id); -- Recursive procedure that does the work and checks nested packages ------------------------ -- Check_Declarations -- ------------------------ procedure Check_Declarations (Spec : Node_Id) is Decl : Node_Id; Incomplete_Decls : constant Elist_Id := New_Elmt_List; Subp_List : constant Elist_Id := New_Elmt_List; procedure Check_Pragma_Import (P : Node_Id); -- If a pragma import applies to a previous subprogram, the -- enclosing unit may not need a body. The processing is syntactic -- and does not require a declaration to be analyzed. The code -- below also handles pragma Import when applied to a subprogram -- that renames another. In this case the pragma applies to the -- renamed entity. -- -- Chains of multiple renames are not handled by the code below. -- It is probably impossible to handle all cases without proper -- name resolution. In such cases the algorithm is conservative -- and will indicate that a body is needed??? ------------------------- -- Check_Pragma_Import -- ------------------------- procedure Check_Pragma_Import (P : Node_Id) is Arg : Node_Id; Prev_Id : Elmt_Id; Subp_Id : Elmt_Id; Imported : Node_Id; procedure Remove_Homonyms (E : Node_Id); -- Make one pass over list of subprograms. Called again if -- subprogram is a renaming. E is known to be an identifier. --------------------- -- Remove_Homonyms -- --------------------- procedure Remove_Homonyms (E : Node_Id) is R : Entity_Id := Empty; -- Name of renamed entity, if any begin Subp_Id := First_Elmt (Subp_List); while Present (Subp_Id) loop if Chars (Node (Subp_Id)) = Chars (E) then if Nkind (Parent (Parent (Node (Subp_Id)))) /= N_Subprogram_Renaming_Declaration then Prev_Id := Subp_Id; Next_Elmt (Subp_Id); Remove_Elmt (Subp_List, Prev_Id); else R := Name (Parent (Parent (Node (Subp_Id)))); exit; end if; else Next_Elmt (Subp_Id); end if; end loop; if Present (R) then if Nkind (R) = N_Identifier then Remove_Homonyms (R); elsif Nkind (R) = N_Selected_Component then Remove_Homonyms (Selector_Name (R)); -- Renaming of attribute else null; end if; end if; end Remove_Homonyms; -- Start of processing for Check_Pragma_Import begin -- Find name of entity in Import pragma. We have not analyzed -- the construct, so we must guard against syntax errors. Arg := Next (First (Pragma_Argument_Associations (P))); if No (Arg) or else Nkind (Expression (Arg)) /= N_Identifier then return; else Imported := Expression (Arg); end if; Remove_Homonyms (Imported); end Check_Pragma_Import; -- Start of processing for Check_Declarations begin -- Search for Elaborate Body pragma Decl := First (Visible_Declarations (Spec)); while Present (Decl) and then Nkind (Decl) = N_Pragma loop if Get_Pragma_Id (Decl) = Pragma_Elaborate_Body then Set_Body_Required (Library_Unit (N)); return; end if; Next (Decl); end loop; -- Look for declarations that require the presence of a body. We -- have already skipped pragmas at the start of the list. while Present (Decl) loop -- Subprogram that comes from source means body may be needed. -- Save for subsequent examination of import pragmas. if Comes_From_Source (Decl) and then (Nkind_In (Decl, N_Subprogram_Declaration, N_Subprogram_Renaming_Declaration, N_Generic_Subprogram_Declaration)) then Append_Elmt (Defining_Entity (Decl), Subp_List); -- Package declaration of generic package declaration. We need -- to recursively examine nested declarations. elsif Nkind_In (Decl, N_Package_Declaration, N_Generic_Package_Declaration) then Check_Declarations (Specification (Decl)); elsif Nkind (Decl) = N_Pragma and then Pragma_Name (Decl) = Name_Import then Check_Pragma_Import (Decl); end if; Next (Decl); end loop; -- Same set of tests for private part. In addition to subprograms -- detect the presence of Taft Amendment types (incomplete types -- completed in the body). Decl := First (Private_Declarations (Spec)); while Present (Decl) loop if Comes_From_Source (Decl) and then (Nkind_In (Decl, N_Subprogram_Declaration, N_Subprogram_Renaming_Declaration, N_Generic_Subprogram_Declaration)) then Append_Elmt (Defining_Entity (Decl), Subp_List); elsif Nkind_In (Decl, N_Package_Declaration, N_Generic_Package_Declaration) then Check_Declarations (Specification (Decl)); -- Collect incomplete type declarations for separate pass elsif Nkind (Decl) = N_Incomplete_Type_Declaration then Append_Elmt (Decl, Incomplete_Decls); elsif Nkind (Decl) = N_Pragma and then Pragma_Name (Decl) = Name_Import then Check_Pragma_Import (Decl); end if; Next (Decl); end loop; -- Now check incomplete declarations to locate Taft amendment -- types. This can be done by examining the defining identifiers -- of type declarations without real semantic analysis. declare Inc : Elmt_Id; begin Inc := First_Elmt (Incomplete_Decls); while Present (Inc) loop Decl := Next (Node (Inc)); while Present (Decl) loop if Nkind (Decl) = N_Full_Type_Declaration and then Chars (Defining_Identifier (Decl)) = Chars (Defining_Identifier (Node (Inc))) then exit; end if; Next (Decl); end loop; -- If no completion, this is a TAT, and a body is needed if No (Decl) then Set_Body_Required (Library_Unit (N)); return; end if; Next_Elmt (Inc); end loop; end; -- Finally, check whether there are subprograms that still require -- a body, i.e. are not renamings or null. if not Is_Empty_Elmt_List (Subp_List) then declare Subp_Id : Elmt_Id; Spec : Node_Id; begin Subp_Id := First_Elmt (Subp_List); Spec := Parent (Node (Subp_Id)); while Present (Subp_Id) loop if Nkind (Parent (Spec)) = N_Subprogram_Renaming_Declaration then null; elsif Nkind (Spec) = N_Procedure_Specification and then Null_Present (Spec) then null; else Set_Body_Required (Library_Unit (N)); return; end if; Next_Elmt (Subp_Id); end loop; end; end if; end Check_Declarations; -- Start of processing for Check_Body_Required begin -- If this is an imported package (Java and CIL usage) no body is -- needed. Scan list of pragmas that may follow a compilation unit -- to look for a relevant pragma Import. if Present (PA) then declare Prag : Node_Id; begin Prag := First (PA); while Present (Prag) loop if Nkind (Prag) = N_Pragma and then Get_Pragma_Id (Prag) = Pragma_Import then return; end if; Next (Prag); end loop; end; end if; Check_Declarations (Specification (P_Unit)); end Check_Body_Required; ----------------------------- -- Has_Limited_With_Clause -- ----------------------------- function Has_Limited_With_Clause (C_Unit : Entity_Id; Pack : Entity_Id) return Boolean is Par : Entity_Id; Par_Unit : Node_Id; begin Par := C_Unit; while Present (Par) loop if Ekind (Par) /= E_Package then exit; end if; -- Retrieve the Compilation_Unit node for Par and determine if -- its context clauses contain a limited with for Pack. Par_Unit := Parent (Parent (Parent (Par))); if Nkind (Par_Unit) = N_Package_Declaration then Par_Unit := Parent (Par_Unit); end if; if Has_With_Clause (Par_Unit, Pack, True) then return True; end if; -- If there are more ancestors, climb up the tree, otherwise we -- are done. if Is_Child_Unit (Par) then Par := Scope (Par); else exit; end if; end loop; return False; end Has_Limited_With_Clause; ---------------------------------- -- Is_Visible_Through_Renamings -- ---------------------------------- function Is_Visible_Through_Renamings (P : Entity_Id) return Boolean is Kind : constant Node_Kind := Nkind (Unit (Cunit (Current_Sem_Unit))); Aux_Unit : Node_Id; Item : Node_Id; Decl : Entity_Id; begin -- Example of the error detected by this subprogram: -- package P is -- type T is ... -- end P; -- with P; -- package Q is -- package Ren_P renames P; -- end Q; -- with Q; -- package R is ... -- limited with P; -- ERROR -- package R.C is ... Aux_Unit := Cunit (Current_Sem_Unit); loop Item := First (Context_Items (Aux_Unit)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then not Limited_Present (Item) and then Nkind (Unit (Library_Unit (Item))) = N_Package_Declaration then Decl := First (Visible_Declarations (Specification (Unit (Library_Unit (Item))))); while Present (Decl) loop if Nkind (Decl) = N_Package_Renaming_Declaration and then Entity (Name (Decl)) = P then -- Generate the error message only if the current unit -- is a package declaration; in case of subprogram -- bodies and package bodies we just return True to -- indicate that the limited view must not be -- installed. if Kind = N_Package_Declaration then Error_Msg_N ("simultaneous visibility of the limited and " & "unlimited views not allowed", N); Error_Msg_Sloc := Sloc (Item); Error_Msg_NE ("\\ unlimited view of & visible through the " & "context clause #", N, P); Error_Msg_Sloc := Sloc (Decl); Error_Msg_NE ("\\ and the renaming #", N, P); end if; return True; end if; Next (Decl); end loop; end if; Next (Item); end loop; -- If it is a body not acting as spec, follow pointer to the -- corresponding spec, otherwise follow pointer to parent spec. if Present (Library_Unit (Aux_Unit)) and then Nkind_In (Unit (Aux_Unit), N_Package_Body, N_Subprogram_Body) then if Aux_Unit = Library_Unit (Aux_Unit) then -- Aux_Unit is a body that acts as a spec. Clause has -- already been flagged as illegal. return False; else Aux_Unit := Library_Unit (Aux_Unit); end if; else Aux_Unit := Parent_Spec (Unit (Aux_Unit)); end if; exit when No (Aux_Unit); end loop; return False; end Is_Visible_Through_Renamings; -- Start of processing for Install_Limited_Withed_Unit begin pragma Assert (not Limited_View_Installed (N)); -- In case of limited with_clause on subprograms, generics, instances, -- or renamings, the corresponding error was previously posted and we -- have nothing to do here. If the file is missing altogether, it has -- no source location. if Nkind (P_Unit) /= N_Package_Declaration or else Sloc (P_Unit) = No_Location then return; end if; P := Defining_Unit_Name (Specification (P_Unit)); -- Handle child packages if Nkind (P) = N_Defining_Program_Unit_Name then Is_Child_Package := True; P := Defining_Identifier (P); end if; -- Do not install the limited-view if the context of the unit is already -- available through a regular with clause. if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body and then Has_With_Clause (Cunit (Current_Sem_Unit), P) then return; end if; -- Do not install the limited-view if the full-view is already visible -- through renaming declarations. if Is_Visible_Through_Renamings (P) then return; end if; -- Do not install the limited view if this is the unit being analyzed. -- This unusual case will happen when a unit has a limited_with clause -- on one of its children. The compilation of the child forces the load -- of the parent which tries to install the limited view of the child -- again. Installing the limited view must also be disabled when -- compiling the body of the child unit. if P = Cunit_Entity (Current_Sem_Unit) or else (Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body and then P = Main_Unit_Entity) then return; end if; -- This scenario is similar to the one above, the difference is that the -- compilation of sibling Par.Sib forces the load of parent Par which -- tries to install the limited view of Lim_Pack [1]. However Par.Sib -- has a with clause for Lim_Pack [2] in its body, and thus needs the -- non-limited views of all entities from Lim_Pack. -- limited with Lim_Pack; -- [1] -- package Par is ... package Lim_Pack is ... -- with Lim_Pack; -- [2] -- package Par.Sib is ... package body Par.Sib is ... -- In this case Main_Unit_Entity is the spec of Par.Sib and Current_ -- Sem_Unit is the body of Par.Sib. if Ekind (P) = E_Package and then Ekind (Main_Unit_Entity) = E_Package and then Is_Child_Unit (Main_Unit_Entity) -- The body has a regular with clause and then Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body and then Has_With_Clause (Cunit (Current_Sem_Unit), P) -- One of the ancestors has a limited with clause and then Nkind (Parent (Parent (Main_Unit_Entity))) = N_Package_Specification and then Has_Limited_With_Clause (Scope (Main_Unit_Entity), P) then return; end if; -- A common use of the limited-with is to have a limited-with in the -- package spec, and a normal with in its package body. For example: -- limited with X; -- [1] -- package A is ... -- with X; -- [2] -- package body A is ... -- The compilation of A's body installs the context clauses found at [2] -- and then the context clauses of its specification (found at [1]). As -- a consequence, at [1] the specification of X has been analyzed and it -- is immediately visible. According to the semantics of limited-with -- context clauses we don't install the limited view because the full -- view of X supersedes its limited view. if Analyzed (P_Unit) and then (Is_Immediately_Visible (P) or else (Is_Child_Package and then Is_Visible_Child_Unit (P))) then -- The presence of both the limited and the analyzed nonlimited view -- may also be an error, such as an illegal context for a limited -- with_clause. In that case, do not process the context item at all. if Error_Posted (N) then return; end if; if Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body then declare Item : Node_Id; begin Item := First (Context_Items (Cunit (Current_Sem_Unit))); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Comes_From_Source (Item) and then Entity (Name (Item)) = P then return; end if; Next (Item); end loop; end; -- If this is a child body, assume that the nonlimited with_clause -- appears in an ancestor. Could be refined ??? if Is_Child_Unit (Defining_Entity (Unit (Library_Unit (Cunit (Current_Sem_Unit))))) then return; end if; else -- If in package declaration, nonlimited view brought in from -- parent unit or some error condition. return; end if; end if; if Debug_Flag_I then Write_Str ("install limited view of "); Write_Name (Chars (P)); Write_Eol; end if; -- If the unit has not been analyzed and the limited view has not been -- already installed then we install it. if not Analyzed (P_Unit) then if not In_Chain (P) then -- Minimum decoration Set_Ekind (P, E_Package); Set_Etype (P, Standard_Void_Type); Set_Scope (P, Standard_Standard); if Is_Child_Package then Set_Is_Child_Unit (P); Set_Is_Visible_Child_Unit (P); Set_Scope (P, Defining_Entity (Unit (Parent_Spec (P_Unit)))); end if; -- Place entity on visibility structure Set_Homonym (P, Current_Entity (P)); Set_Current_Entity (P); if Debug_Flag_I then Write_Str (" (homonym) chain "); Write_Name (Chars (P)); Write_Eol; end if; -- Install the incomplete view. The first element of the limited -- view is a header (an E_Package entity) used to reference the -- first shadow entity in the private part of the package. Lim_Header := Limited_View (P); Lim_Typ := First_Entity (Lim_Header); while Present (Lim_Typ) and then Lim_Typ /= First_Private_Entity (Lim_Header) loop Set_Homonym (Lim_Typ, Current_Entity (Lim_Typ)); Set_Current_Entity (Lim_Typ); if Debug_Flag_I then Write_Str (" (homonym) chain "); Write_Name (Chars (Lim_Typ)); Write_Eol; end if; Next_Entity (Lim_Typ); end loop; end if; -- If the unit appears in a previous regular with_clause, the regular -- entities of the public part of the withed package must be replaced -- by the shadow ones. -- This code must be kept synchronized with the code that replaces the -- shadow entities by the real entities (see body of Remove_Limited -- With_Clause); otherwise the contents of the homonym chains are not -- consistent. else -- Hide all the type entities of the public part of the package to -- avoid its usage. This is needed to cover all the subtype decla- -- rations because we do not remove them from the homonym chain. E := First_Entity (P); while Present (E) and then E /= First_Private_Entity (P) loop if Is_Type (E) then Set_Was_Hidden (E, Is_Hidden (E)); Set_Is_Hidden (E); end if; Next_Entity (E); end loop; -- Replace the real entities by the shadow entities of the limited -- view. The first element of the limited view is a header that is -- used to reference the first shadow entity in the private part -- of the package. Successive elements are the limited views of the -- type (including regular incomplete types) declared in the package. Lim_Header := Limited_View (P); Lim_Typ := First_Entity (Lim_Header); while Present (Lim_Typ) and then Lim_Typ /= First_Private_Entity (Lim_Header) loop pragma Assert (not In_Chain (Lim_Typ)); -- Do not unchain nested packages and child units if Ekind (Lim_Typ) /= E_Package and then not Is_Child_Unit (Lim_Typ) then declare Prev : Entity_Id; begin Prev := Current_Entity (Lim_Typ); E := Prev; -- Replace E in the homonyms list, so that the limited view -- becomes available. if E = Non_Limited_View (Lim_Typ) then Set_Homonym (Lim_Typ, Homonym (Prev)); Set_Current_Entity (Lim_Typ); else loop E := Homonym (Prev); -- E may have been removed when installing a previous -- limited_with_clause. exit when No (E); exit when E = Non_Limited_View (Lim_Typ); Prev := Homonym (Prev); end loop; if Present (E) then Set_Homonym (Lim_Typ, Homonym (Homonym (Prev))); Set_Homonym (Prev, Lim_Typ); end if; end if; end; if Debug_Flag_I then Write_Str (" (homonym) chain "); Write_Name (Chars (Lim_Typ)); Write_Eol; end if; end if; Next_Entity (Lim_Typ); end loop; end if; -- The package must be visible while the limited-with clause is active -- because references to the type P.T must resolve in the usual way. -- In addition, we remember that the limited-view has been installed to -- uninstall it at the point of context removal. Set_Is_Immediately_Visible (P); Set_Limited_View_Installed (N); -- If unit has not been analyzed in some previous context, check -- (imperfectly ???) whether it might need a body. if not Analyzed (P_Unit) then Check_Body_Required; end if; -- If the package in the limited_with clause is a child unit, the clause -- is unanalyzed and appears as a selected component. Recast it as an -- expanded name so that the entity can be properly set. Use entity of -- parent, if available, for higher ancestors in the name. if Nkind (Name (N)) = N_Selected_Component then declare Nam : Node_Id; Ent : Entity_Id; begin Nam := Name (N); Ent := P; while Nkind (Nam) = N_Selected_Component and then Present (Ent) loop Change_Selected_Component_To_Expanded_Name (Nam); -- Set entity of parent identifiers if the unit is a child -- unit. This ensures that the tree is properly formed from -- semantic point of view (e.g. for ASIS queries). The unit -- entities are not fully analyzed, so we need to follow unit -- links in the tree. Set_Entity (Nam, Ent); Nam := Prefix (Nam); Ent := Defining_Entity (Unit (Parent_Spec (Unit_Declaration_Node (Ent)))); -- Set entity of last ancestor if Nkind (Nam) = N_Identifier then Set_Entity (Nam, Ent); end if; end loop; end; end if; Set_Entity (Name (N), P); Set_From_With_Type (P); end Install_Limited_Withed_Unit; ------------------------- -- Install_Withed_Unit -- ------------------------- procedure Install_Withed_Unit (With_Clause : Node_Id; Private_With_OK : Boolean := False) is Uname : constant Entity_Id := Entity (Name (With_Clause)); P : constant Entity_Id := Scope (Uname); begin -- Ada 2005 (AI-262): Do not install the private withed unit if we are -- compiling a package declaration and the Private_With_OK flag was not -- set by the caller. These declarations will be installed later (before -- analyzing the private part of the package). if Private_Present (With_Clause) and then Nkind (Unit (Parent (With_Clause))) = N_Package_Declaration and then not (Private_With_OK) then return; end if; if Debug_Flag_I then if Private_Present (With_Clause) then Write_Str ("install private withed unit "); else Write_Str ("install withed unit "); end if; Write_Name (Chars (Uname)); Write_Eol; end if; -- We do not apply the restrictions to an internal unit unless we are -- compiling the internal unit as a main unit. This check is also -- skipped for dummy units (for missing packages). if Sloc (Uname) /= No_Location and then (not Is_Internal_File_Name (Unit_File_Name (Current_Sem_Unit)) or else Current_Sem_Unit = Main_Unit) then Check_Restricted_Unit (Unit_Name (Get_Source_Unit (Uname)), With_Clause); end if; if P /= Standard_Standard then -- If the unit is not analyzed after analysis of the with clause and -- it is an instantiation then it awaits a body and is the main unit. -- Its appearance in the context of some other unit indicates a -- circular dependency (DEC suite perversity). if not Analyzed (Uname) and then Nkind (Parent (Uname)) = N_Package_Instantiation then Error_Msg_N ("instantiation depends on itself", Name (With_Clause)); elsif not Is_Visible_Child_Unit (Uname) then -- Abandon processing in case of previous errors if No (Scope (Uname)) then pragma Assert (Serious_Errors_Detected /= 0); return; end if; Set_Is_Visible_Child_Unit (Uname); -- If the child unit appears in the context of its parent, it is -- immediately visible. if In_Open_Scopes (Scope (Uname)) then Set_Is_Immediately_Visible (Uname); end if; if Is_Generic_Instance (Uname) and then Ekind (Uname) in Subprogram_Kind then -- Set flag as well on the visible entity that denotes the -- instance, which renames the current one. Set_Is_Visible_Child_Unit (Related_Instance (Defining_Entity (Unit (Library_Unit (With_Clause))))); end if; -- The parent unit may have been installed already, and may have -- appeared in a use clause. if In_Use (Scope (Uname)) then Set_Is_Potentially_Use_Visible (Uname); end if; Set_Context_Installed (With_Clause); end if; elsif not Is_Immediately_Visible (Uname) then if not Private_Present (With_Clause) or else Private_With_OK then Set_Is_Immediately_Visible (Uname); end if; Set_Context_Installed (With_Clause); end if; -- A with-clause overrides a with-type clause: there are no restric- -- tions on the use of package entities. if Ekind (Uname) = E_Package then Set_From_With_Type (Uname, False); end if; -- Ada 2005 (AI-377): it is illegal for a with_clause to name a child -- unit if there is a visible homograph for it declared in the same -- declarative region. This pathological case can only arise when an -- instance I1 of a generic unit G1 has an explicit child unit I1.G2, -- G1 has a generic child also named G2, and the context includes with_ -- clauses for both I1.G2 and for G1.G2, making an implicit declaration -- of I1.G2 visible as well. If the child unit is named Standard, do -- not apply the check to the Standard package itself. if Is_Child_Unit (Uname) and then Is_Visible_Child_Unit (Uname) and then Ada_Version >= Ada_2005 then declare Decl1 : constant Node_Id := Unit_Declaration_Node (P); Decl2 : Node_Id; P2 : Entity_Id; U2 : Entity_Id; begin U2 := Homonym (Uname); while Present (U2) and then U2 /= Standard_Standard loop P2 := Scope (U2); Decl2 := Unit_Declaration_Node (P2); if Is_Child_Unit (U2) and then Is_Visible_Child_Unit (U2) then if Is_Generic_Instance (P) and then Nkind (Decl1) = N_Package_Declaration and then Generic_Parent (Specification (Decl1)) = P2 then Error_Msg_N ("illegal with_clause", With_Clause); Error_Msg_N ("\child unit has visible homograph" & " (RM 8.3(26), 10.1.1(19))", With_Clause); exit; elsif Is_Generic_Instance (P2) and then Nkind (Decl2) = N_Package_Declaration and then Generic_Parent (Specification (Decl2)) = P then -- With_clause for child unit of instance appears before -- in the context. We want to place the error message on -- it, not on the generic child unit itself. declare Prev_Clause : Node_Id; begin Prev_Clause := First (List_Containing (With_Clause)); while Entity (Name (Prev_Clause)) /= U2 loop Next (Prev_Clause); end loop; pragma Assert (Present (Prev_Clause)); Error_Msg_N ("illegal with_clause", Prev_Clause); Error_Msg_N ("\child unit has visible homograph" & " (RM 8.3(26), 10.1.1(19))", Prev_Clause); exit; end; end if; end if; U2 := Homonym (U2); end loop; end; end if; end Install_Withed_Unit; ------------------- -- Is_Child_Spec -- ------------------- function Is_Child_Spec (Lib_Unit : Node_Id) return Boolean is K : constant Node_Kind := Nkind (Lib_Unit); begin return (K in N_Generic_Declaration or else K in N_Generic_Instantiation or else K in N_Generic_Renaming_Declaration or else K = N_Package_Declaration or else K = N_Package_Renaming_Declaration or else K = N_Subprogram_Declaration or else K = N_Subprogram_Renaming_Declaration) and then Present (Parent_Spec (Lib_Unit)); end Is_Child_Spec; ------------------------------------ -- Is_Legal_Shadow_Entity_In_Body -- ------------------------------------ function Is_Legal_Shadow_Entity_In_Body (T : Entity_Id) return Boolean is C_Unit : constant Node_Id := Cunit (Current_Sem_Unit); begin return Nkind (Unit (C_Unit)) = N_Package_Body and then Has_With_Clause (C_Unit, Cunit_Entity (Get_Source_Unit (Non_Limited_View (T)))); end Is_Legal_Shadow_Entity_In_Body; ----------------------- -- Load_Needed_Body -- ----------------------- -- N is a generic unit named in a with clause, or else it is a unit that -- contains a generic unit or an inlined function. In order to perform an -- instantiation, the body of the unit must be present. If the unit itself -- is generic, we assume that an instantiation follows, and load & analyze -- the body unconditionally. This forces analysis of the spec as well. -- If the unit is not generic, but contains a generic unit, it is loaded on -- demand, at the point of instantiation (see ch12). procedure Load_Needed_Body (N : Node_Id; OK : out Boolean; Do_Analyze : Boolean := True) is Body_Name : Unit_Name_Type; Unum : Unit_Number_Type; Save_Style_Check : constant Boolean := Opt.Style_Check; -- The loading and analysis is done with style checks off begin if not GNAT_Mode then Style_Check := False; end if; Body_Name := Get_Body_Name (Get_Unit_Name (Unit (N))); Unum := Load_Unit (Load_Name => Body_Name, Required => False, Subunit => False, Error_Node => N, Renamings => True); if Unum = No_Unit then OK := False; else Compiler_State := Analyzing; -- reset after load if not Fatal_Error (Unum) or else Try_Semantics then if Debug_Flag_L then Write_Str ("*** Loaded generic body"); Write_Eol; end if; if Do_Analyze then Semantics (Cunit (Unum)); end if; end if; OK := True; end if; Style_Check := Save_Style_Check; end Load_Needed_Body; ------------------------- -- Build_Limited_Views -- ------------------------- procedure Build_Limited_Views (N : Node_Id) is Unum : constant Unit_Number_Type := Get_Source_Unit (Library_Unit (N)); P : constant Entity_Id := Cunit_Entity (Unum); Spec : Node_Id; -- To denote a package specification Lim_Typ : Entity_Id; -- To denote shadow entities Comp_Typ : Entity_Id; -- To denote real entities Lim_Header : Entity_Id; -- Package entity Last_Lim_E : Entity_Id := Empty; -- Last limited entity built Last_Pub_Lim_E : Entity_Id; -- To set the first private entity procedure Decorate_Incomplete_Type (E : Entity_Id; Scop : Entity_Id); -- Add attributes of an incomplete type to a shadow entity. The same -- attributes are placed on the real entity, so that gigi receives -- a consistent view. procedure Decorate_Package_Specification (P : Entity_Id); -- Add attributes of a package entity to the entity in a package -- declaration procedure Decorate_Tagged_Type (Loc : Source_Ptr; T : Entity_Id; Scop : Entity_Id; Mark : Boolean := False); -- Set basic attributes of tagged type T, including its class-wide type. -- The parameters Loc, Scope are used to decorate the class-wide type. -- Use flag Mark to label the class-wide type as Materialize_Entity. procedure Build_Chain (Scope : Entity_Id; First_Decl : Node_Id); -- Construct list of shadow entities and attach it to entity of -- package that is mentioned in a limited_with clause. function New_Internal_Shadow_Entity (Kind : Entity_Kind; Sloc_Value : Source_Ptr; Id_Char : Character) return Entity_Id; -- Build a new internal entity and append it to the list of shadow -- entities available through the limited-header ----------------- -- Build_Chain -- ----------------- procedure Build_Chain (Scope : Entity_Id; First_Decl : Node_Id) is Analyzed_Unit : constant Boolean := Analyzed (Cunit (Unum)); Is_Tagged : Boolean; Decl : Node_Id; begin Decl := First_Decl; while Present (Decl) loop -- For each library_package_declaration in the environment, there -- is an implicit declaration of a *limited view* of that library -- package. The limited view of a package contains: -- * For each nested package_declaration, a declaration of the -- limited view of that package, with the same defining- -- program-unit name. -- * For each type_declaration in the visible part, an incomplete -- type-declaration with the same defining_identifier, whose -- completion is the type_declaration. If the type_declaration -- is tagged, then the incomplete_type_declaration is tagged -- incomplete. -- The partial view is tagged if the declaration has the -- explicit keyword, or else if it is a type extension, both -- of which can be ascertained syntactically. if Nkind (Decl) = N_Full_Type_Declaration then Is_Tagged := (Nkind (Type_Definition (Decl)) = N_Record_Definition and then Tagged_Present (Type_Definition (Decl))) or else (Nkind (Type_Definition (Decl)) = N_Derived_Type_Definition and then Present (Record_Extension_Part (Type_Definition (Decl)))); Comp_Typ := Defining_Identifier (Decl); if not Analyzed_Unit then if Is_Tagged then Decorate_Tagged_Type (Sloc (Decl), Comp_Typ, Scope, True); else Decorate_Incomplete_Type (Comp_Typ, Scope); end if; end if; -- Create shadow entity for type Lim_Typ := New_Internal_Shadow_Entity (Kind => Ekind (Comp_Typ), Sloc_Value => Sloc (Comp_Typ), Id_Char => 'Z'); Set_Chars (Lim_Typ, Chars (Comp_Typ)); Set_Parent (Lim_Typ, Parent (Comp_Typ)); Set_From_With_Type (Lim_Typ); if Is_Tagged then Decorate_Tagged_Type (Sloc (Decl), Lim_Typ, Scope); else Decorate_Incomplete_Type (Lim_Typ, Scope); end if; Set_Non_Limited_View (Lim_Typ, Comp_Typ); Set_Private_Dependents (Lim_Typ, New_Elmt_List); elsif Nkind_In (Decl, N_Private_Type_Declaration, N_Incomplete_Type_Declaration, N_Task_Type_Declaration, N_Protected_Type_Declaration) then Comp_Typ := Defining_Identifier (Decl); Is_Tagged := Nkind_In (Decl, N_Private_Type_Declaration, N_Incomplete_Type_Declaration) and then Tagged_Present (Decl); if not Analyzed_Unit then if Is_Tagged then Decorate_Tagged_Type (Sloc (Decl), Comp_Typ, Scope, True); else Decorate_Incomplete_Type (Comp_Typ, Scope); end if; end if; Lim_Typ := New_Internal_Shadow_Entity (Kind => Ekind (Comp_Typ), Sloc_Value => Sloc (Comp_Typ), Id_Char => 'Z'); Set_Chars (Lim_Typ, Chars (Comp_Typ)); Set_Parent (Lim_Typ, Parent (Comp_Typ)); Set_From_With_Type (Lim_Typ); if Is_Tagged then Decorate_Tagged_Type (Sloc (Decl), Lim_Typ, Scope); else Decorate_Incomplete_Type (Lim_Typ, Scope); end if; Set_Non_Limited_View (Lim_Typ, Comp_Typ); -- Initialize Private_Depedents, so the field has the proper -- type, even though the list will remain empty. Set_Private_Dependents (Lim_Typ, New_Elmt_List); elsif Nkind (Decl) = N_Private_Extension_Declaration then Comp_Typ := Defining_Identifier (Decl); if not Analyzed_Unit then Decorate_Tagged_Type (Sloc (Decl), Comp_Typ, Scope, True); end if; -- Create shadow entity for type Lim_Typ := New_Internal_Shadow_Entity (Kind => Ekind (Comp_Typ), Sloc_Value => Sloc (Comp_Typ), Id_Char => 'Z'); Set_Chars (Lim_Typ, Chars (Comp_Typ)); Set_Parent (Lim_Typ, Parent (Comp_Typ)); Set_From_With_Type (Lim_Typ); Decorate_Tagged_Type (Sloc (Decl), Lim_Typ, Scope); Set_Non_Limited_View (Lim_Typ, Comp_Typ); elsif Nkind (Decl) = N_Package_Declaration then -- Local package declare Spec : constant Node_Id := Specification (Decl); begin Comp_Typ := Defining_Unit_Name (Spec); if not Analyzed (Cunit (Unum)) then Decorate_Package_Specification (Comp_Typ); Set_Scope (Comp_Typ, Scope); end if; Lim_Typ := New_Internal_Shadow_Entity (Kind => Ekind (Comp_Typ), Sloc_Value => Sloc (Comp_Typ), Id_Char => 'Z'); Decorate_Package_Specification (Lim_Typ); Set_Scope (Lim_Typ, Scope); Set_Chars (Lim_Typ, Chars (Comp_Typ)); Set_Parent (Lim_Typ, Parent (Comp_Typ)); Set_From_With_Type (Lim_Typ); -- Note: The non_limited_view attribute is not used -- for local packages. Build_Chain (Scope => Lim_Typ, First_Decl => First (Visible_Declarations (Spec))); end; end if; Next (Decl); end loop; end Build_Chain; ------------------------------ -- Decorate_Incomplete_Type -- ------------------------------ procedure Decorate_Incomplete_Type (E : Entity_Id; Scop : Entity_Id) is begin Set_Ekind (E, E_Incomplete_Type); Set_Scope (E, Scop); Set_Etype (E, E); Set_Is_First_Subtype (E, True); Set_Stored_Constraint (E, No_Elist); Set_Full_View (E, Empty); Init_Size_Align (E); end Decorate_Incomplete_Type; -------------------------- -- Decorate_Tagged_Type -- -------------------------- procedure Decorate_Tagged_Type (Loc : Source_Ptr; T : Entity_Id; Scop : Entity_Id; Mark : Boolean := False) is CW : Entity_Id; begin Decorate_Incomplete_Type (T, Scop); Set_Is_Tagged_Type (T); -- Build corresponding class_wide type, if not previously done -- Note: The class-wide entity is shared by the limited-view -- and the full-view. if No (Class_Wide_Type (T)) then CW := New_External_Entity (E_Void, Scope (T), Loc, T, 'C', 0, 'T'); -- Set parent to be the same as the parent of the tagged type. -- We need a parent field set, and it is supposed to point to -- the declaration of the type. The tagged type declaration -- essentially declares two separate types, the tagged type -- itself and the corresponding class-wide type, so it is -- reasonable for the parent fields to point to the declaration -- in both cases. Set_Parent (CW, Parent (T)); -- Set remaining fields of classwide type Set_Ekind (CW, E_Class_Wide_Type); Set_Etype (CW, T); Set_Scope (CW, Scop); Set_Is_Tagged_Type (CW); Set_Is_First_Subtype (CW, True); Init_Size_Align (CW); Set_Has_Unknown_Discriminants (CW, True); Set_Class_Wide_Type (CW, CW); Set_Equivalent_Type (CW, Empty); Set_From_With_Type (CW, From_With_Type (T)); Set_Materialize_Entity (CW, Mark); -- Link type to its class-wide type Set_Class_Wide_Type (T, CW); end if; end Decorate_Tagged_Type; ------------------------------------ -- Decorate_Package_Specification -- ------------------------------------ procedure Decorate_Package_Specification (P : Entity_Id) is begin -- Place only the most basic attributes Set_Ekind (P, E_Package); Set_Etype (P, Standard_Void_Type); end Decorate_Package_Specification; -------------------------------- -- New_Internal_Shadow_Entity -- -------------------------------- function New_Internal_Shadow_Entity (Kind : Entity_Kind; Sloc_Value : Source_Ptr; Id_Char : Character) return Entity_Id is E : constant Entity_Id := Make_Temporary (Sloc_Value, Id_Char); begin Set_Ekind (E, Kind); Set_Is_Internal (E, True); if Kind in Type_Kind then Init_Size_Align (E); end if; Append_Entity (E, Lim_Header); Last_Lim_E := E; return E; end New_Internal_Shadow_Entity; -- Start of processing for Build_Limited_Views begin pragma Assert (Limited_Present (N)); -- A library_item mentioned in a limited_with_clause is a package -- declaration, not a subprogram declaration, generic declaration, -- generic instantiation, or package renaming declaration. case Nkind (Unit (Library_Unit (N))) is when N_Package_Declaration => null; when N_Subprogram_Declaration => Error_Msg_N ("subprograms not allowed in " & "limited with_clauses", N); return; when N_Generic_Package_Declaration | N_Generic_Subprogram_Declaration => Error_Msg_N ("generics not allowed in " & "limited with_clauses", N); return; when N_Generic_Instantiation => Error_Msg_N ("generic instantiations not allowed in " & "limited with_clauses", N); return; when N_Generic_Renaming_Declaration => Error_Msg_N ("generic renamings not allowed in " & "limited with_clauses", N); return; when N_Subprogram_Renaming_Declaration => Error_Msg_N ("renamed subprograms not allowed in " & "limited with_clauses", N); return; when N_Package_Renaming_Declaration => Error_Msg_N ("renamed packages not allowed in " & "limited with_clauses", N); return; when others => raise Program_Error; end case; -- Check if the chain is already built Spec := Specification (Unit (Library_Unit (N))); if Limited_View_Installed (Spec) then return; end if; Set_Ekind (P, E_Package); -- Build the header of the limited_view Lim_Header := Make_Temporary (Sloc (N), 'Z'); Set_Ekind (Lim_Header, E_Package); Set_Is_Internal (Lim_Header); Set_Limited_View (P, Lim_Header); -- Create the auxiliary chain. All the shadow entities are appended to -- the list of entities of the limited-view header Build_Chain (Scope => P, First_Decl => First (Visible_Declarations (Spec))); -- Save the last built shadow entity. It is needed later to set the -- reference to the first shadow entity in the private part Last_Pub_Lim_E := Last_Lim_E; -- Ada 2005 (AI-262): Add the limited view of the private declarations -- Required to give support to limited-private-with clauses Build_Chain (Scope => P, First_Decl => First (Private_Declarations (Spec))); if Last_Pub_Lim_E /= Empty then Set_First_Private_Entity (Lim_Header, Next_Entity (Last_Pub_Lim_E)); else Set_First_Private_Entity (Lim_Header, First_Entity (P)); end if; Set_Limited_View_Installed (Spec); end Build_Limited_Views; ------------------------------- -- Check_Body_Needed_For_SAL -- ------------------------------- procedure Check_Body_Needed_For_SAL (Unit_Name : Entity_Id) is function Entity_Needs_Body (E : Entity_Id) return Boolean; -- Determine whether use of entity E might require the presence of its -- body. For a package this requires a recursive traversal of all nested -- declarations. --------------------------- -- Entity_Needed_For_SAL -- --------------------------- function Entity_Needs_Body (E : Entity_Id) return Boolean is Ent : Entity_Id; begin if Is_Subprogram (E) and then Has_Pragma_Inline (E) then return True; elsif Ekind_In (E, E_Generic_Function, E_Generic_Procedure) then return True; elsif Ekind (E) = E_Generic_Package and then Nkind (Unit_Declaration_Node (E)) = N_Generic_Package_Declaration and then Present (Corresponding_Body (Unit_Declaration_Node (E))) then return True; elsif Ekind (E) = E_Package and then Nkind (Unit_Declaration_Node (E)) = N_Package_Declaration and then Present (Corresponding_Body (Unit_Declaration_Node (E))) then Ent := First_Entity (E); while Present (Ent) loop if Entity_Needs_Body (Ent) then return True; end if; Next_Entity (Ent); end loop; return False; else return False; end if; end Entity_Needs_Body; -- Start of processing for Check_Body_Needed_For_SAL begin if Ekind (Unit_Name) = E_Generic_Package and then Nkind (Unit_Declaration_Node (Unit_Name)) = N_Generic_Package_Declaration and then Present (Corresponding_Body (Unit_Declaration_Node (Unit_Name))) then Set_Body_Needed_For_SAL (Unit_Name); elsif Ekind_In (Unit_Name, E_Generic_Procedure, E_Generic_Function) then Set_Body_Needed_For_SAL (Unit_Name); elsif Is_Subprogram (Unit_Name) and then Nkind (Unit_Declaration_Node (Unit_Name)) = N_Subprogram_Declaration and then Has_Pragma_Inline (Unit_Name) then Set_Body_Needed_For_SAL (Unit_Name); elsif Ekind (Unit_Name) = E_Subprogram_Body then Check_Body_Needed_For_SAL (Corresponding_Spec (Unit_Declaration_Node (Unit_Name))); elsif Ekind (Unit_Name) = E_Package and then Entity_Needs_Body (Unit_Name) then Set_Body_Needed_For_SAL (Unit_Name); elsif Ekind (Unit_Name) = E_Package_Body and then Nkind (Unit_Declaration_Node (Unit_Name)) = N_Package_Body then Check_Body_Needed_For_SAL (Corresponding_Spec (Unit_Declaration_Node (Unit_Name))); end if; end Check_Body_Needed_For_SAL; -------------------- -- Remove_Context -- -------------------- procedure Remove_Context (N : Node_Id) is Lib_Unit : constant Node_Id := Unit (N); begin -- If this is a child unit, first remove the parent units if Is_Child_Spec (Lib_Unit) then Remove_Parents (Lib_Unit); end if; Remove_Context_Clauses (N); end Remove_Context; ---------------------------- -- Remove_Context_Clauses -- ---------------------------- procedure Remove_Context_Clauses (N : Node_Id) is Item : Node_Id; Unit_Name : Entity_Id; begin -- Ada 2005 (AI-50217): We remove the context clauses in two phases: -- limited-views first and regular-views later (to maintain the -- stack model). -- First Phase: Remove limited_with context clauses Item := First (Context_Items (N)); while Present (Item) loop -- We are interested only in with clauses which got installed -- on entry. if Nkind (Item) = N_With_Clause and then Limited_Present (Item) and then Limited_View_Installed (Item) then Remove_Limited_With_Clause (Item); end if; Next (Item); end loop; -- Second Phase: Loop through context items and undo regular -- with_clauses and use_clauses. Item := First (Context_Items (N)); while Present (Item) loop -- We are interested only in with clauses which got installed on -- entry, as indicated by their Context_Installed flag set if Nkind (Item) = N_With_Clause and then Limited_Present (Item) and then Limited_View_Installed (Item) then null; elsif Nkind (Item) = N_With_Clause and then Context_Installed (Item) then -- Remove items from one with'ed unit Unit_Name := Entity (Name (Item)); Remove_Unit_From_Visibility (Unit_Name); Set_Context_Installed (Item, False); elsif Nkind (Item) = N_Use_Package_Clause then End_Use_Package (Item); elsif Nkind (Item) = N_Use_Type_Clause then End_Use_Type (Item); end if; Next (Item); end loop; end Remove_Context_Clauses; -------------------------------- -- Remove_Limited_With_Clause -- -------------------------------- procedure Remove_Limited_With_Clause (N : Node_Id) is P_Unit : constant Entity_Id := Unit (Library_Unit (N)); E : Entity_Id; P : Entity_Id; Lim_Header : Entity_Id; Lim_Typ : Entity_Id; Prev : Entity_Id; begin pragma Assert (Limited_View_Installed (N)); -- In case of limited with_clause on subprograms, generics, instances, -- or renamings, the corresponding error was previously posted and we -- have nothing to do here. if Nkind (P_Unit) /= N_Package_Declaration then return; end if; P := Defining_Unit_Name (Specification (P_Unit)); -- Handle child packages if Nkind (P) = N_Defining_Program_Unit_Name then P := Defining_Identifier (P); end if; if Debug_Flag_I then Write_Str ("remove limited view of "); Write_Name (Chars (P)); Write_Str (" from visibility"); Write_Eol; end if; -- Prepare the removal of the shadow entities from visibility. The first -- element of the limited view is a header (an E_Package entity) that is -- used to reference the first shadow entity in the private part of the -- package Lim_Header := Limited_View (P); Lim_Typ := First_Entity (Lim_Header); -- Remove package and shadow entities from visibility if it has not -- been analyzed if not Analyzed (P_Unit) then Unchain (P); Set_Is_Immediately_Visible (P, False); while Present (Lim_Typ) loop Unchain (Lim_Typ); Next_Entity (Lim_Typ); end loop; -- Otherwise this package has already appeared in the closure and its -- shadow entities must be replaced by its real entities. This code -- must be kept synchronized with the complementary code in Install -- Limited_Withed_Unit. else -- Real entities that are type or subtype declarations were hidden -- from visibility at the point of installation of the limited-view. -- Now we recover the previous value of the hidden attribute. E := First_Entity (P); while Present (E) and then E /= First_Private_Entity (P) loop if Is_Type (E) then Set_Is_Hidden (E, Was_Hidden (E)); end if; Next_Entity (E); end loop; while Present (Lim_Typ) and then Lim_Typ /= First_Private_Entity (Lim_Header) loop -- Nested packages and child units were not unchained if Ekind (Lim_Typ) /= E_Package and then not Is_Child_Unit (Non_Limited_View (Lim_Typ)) then -- If the package has incomplete types, the limited view of the -- incomplete type is in fact never visible (AI05-129) but we -- have created a shadow entity E1 for it, that points to E2, -- a non-limited incomplete type. This in turn has a full view -- E3 that is the full declaration. There is a corresponding -- shadow entity E4. When reinstalling the non-limited view, -- E2 must become the current entity and E3 must be ignored. E := Non_Limited_View (Lim_Typ); if Present (Current_Entity (E)) and then Ekind (Current_Entity (E)) = E_Incomplete_Type and then Full_View (Current_Entity (E)) = E then -- Lim_Typ is the limited view of a full type declaration -- that has a previous incomplete declaration, i.e. E3 from -- the previous description. Nothing to insert. null; else pragma Assert (not In_Chain (E)); Prev := Current_Entity (Lim_Typ); if Prev = Lim_Typ then Set_Current_Entity (E); else while Present (Prev) and then Homonym (Prev) /= Lim_Typ loop Prev := Homonym (Prev); end loop; if Present (Prev) then Set_Homonym (Prev, E); end if; end if; -- Preserve structure of homonym chain Set_Homonym (E, Homonym (Lim_Typ)); end if; end if; Next_Entity (Lim_Typ); end loop; end if; -- Indicate that the limited view of the package is not installed Set_From_With_Type (P, False); Set_Limited_View_Installed (N, False); end Remove_Limited_With_Clause; -------------------- -- Remove_Parents -- -------------------- procedure Remove_Parents (Lib_Unit : Node_Id) is P : Node_Id; P_Name : Entity_Id; P_Spec : Node_Id := Empty; E : Entity_Id; Vis : constant Boolean := Scope_Stack.Table (Scope_Stack.Last).Previous_Visibility; begin if Is_Child_Spec (Lib_Unit) then P_Spec := Parent_Spec (Lib_Unit); elsif Nkind (Lib_Unit) = N_Package_Body and then Nkind (Original_Node (Lib_Unit)) = N_Package_Instantiation then P_Spec := Parent_Spec (Original_Node (Lib_Unit)); end if; if Present (P_Spec) then P := Unit (P_Spec); P_Name := Get_Parent_Entity (P); Remove_Context_Clauses (P_Spec); End_Package_Scope (P_Name); Set_Is_Immediately_Visible (P_Name, Vis); -- Remove from visibility the siblings as well, which are directly -- visible while the parent is in scope. E := First_Entity (P_Name); while Present (E) loop if Is_Child_Unit (E) then Set_Is_Immediately_Visible (E, False); end if; Next_Entity (E); end loop; Set_In_Package_Body (P_Name, False); -- This is the recursive call to remove the context of any higher -- level parent. This recursion ensures that all parents are removed -- in the reverse order of their installation. Remove_Parents (P); end if; end Remove_Parents; --------------------------------- -- Remove_Private_With_Clauses -- --------------------------------- procedure Remove_Private_With_Clauses (Comp_Unit : Node_Id) is Item : Node_Id; function In_Regular_With_Clause (E : Entity_Id) return Boolean; -- Check whether a given unit appears in a regular with_clause. Used to -- determine whether a private_with_clause, implicit or explicit, should -- be ignored. ---------------------------- -- In_Regular_With_Clause -- ---------------------------- function In_Regular_With_Clause (E : Entity_Id) return Boolean is Item : Node_Id; begin Item := First (Context_Items (Comp_Unit)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Entity (Name (Item)) = E and then not Private_Present (Item) then return True; end if; Next (Item); end loop; return False; end In_Regular_With_Clause; -- Start of processing for Remove_Private_With_Clauses begin Item := First (Context_Items (Comp_Unit)); while Present (Item) loop if Nkind (Item) = N_With_Clause and then Private_Present (Item) then -- If private_with_clause is redundant, remove it from context, -- as a small optimization to subsequent handling of private_with -- clauses in other nested packages. if In_Regular_With_Clause (Entity (Name (Item))) then declare Nxt : constant Node_Id := Next (Item); begin Remove (Item); Item := Nxt; end; elsif Limited_Present (Item) then if not Limited_View_Installed (Item) then Remove_Limited_With_Clause (Item); end if; Next (Item); else Remove_Unit_From_Visibility (Entity (Name (Item))); Set_Context_Installed (Item, False); Next (Item); end if; else Next (Item); end if; end loop; end Remove_Private_With_Clauses; --------------------------------- -- Remove_Unit_From_Visibility -- --------------------------------- procedure Remove_Unit_From_Visibility (Unit_Name : Entity_Id) is P : constant Entity_Id := Scope (Unit_Name); begin if Debug_Flag_I then Write_Str ("remove unit "); Write_Name (Chars (Unit_Name)); Write_Str (" from visibility"); Write_Eol; end if; if P /= Standard_Standard then Set_Is_Visible_Child_Unit (Unit_Name, False); end if; Set_Is_Potentially_Use_Visible (Unit_Name, False); Set_Is_Immediately_Visible (Unit_Name, False); end Remove_Unit_From_Visibility; -------- -- sm -- -------- procedure sm is begin null; end sm; ------------- -- Unchain -- ------------- procedure Unchain (E : Entity_Id) is Prev : Entity_Id; begin Prev := Current_Entity (E); if No (Prev) then return; elsif Prev = E then Set_Name_Entity_Id (Chars (E), Homonym (E)); else while Present (Prev) and then Homonym (Prev) /= E loop Prev := Homonym (Prev); end loop; if Present (Prev) then Set_Homonym (Prev, Homonym (E)); end if; end if; if Debug_Flag_I then Write_Str (" (homonym) unchain "); Write_Name (Chars (E)); Write_Eol; end if; end Unchain; end Sem_Ch10;
Go to most recent revision | Compare with Previous | Blame | View Log