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Diffstat (limited to 'gcc-4.4.3/gcc/ada/sem_ch10.adb')
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diff --git a/gcc-4.4.3/gcc/ada/sem_ch10.adb b/gcc-4.4.3/gcc/ada/sem_ch10.adb deleted file mode 100644 index cbdda92aa..000000000 --- a/gcc-4.4.3/gcc/ada/sem_ch10.adb +++ /dev/null @@ -1,5738 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- S E M _ C H 1 0 -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2008, 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 Restrict; use Restrict; -with Rident; use Rident; -with Rtsfind; use Rtsfind; -with Sem; use Sem; -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. - - 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 only 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 Ada05 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, pragma Elaborate 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 or incorrect warnings. The - -- common case is the 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 applied. - - 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 ("?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 ("?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) - - Analyze_Context (N); - - -- 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 - Semantics (Lib_Unit); - 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 only for error checking and consistency - -- purposes, 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. - - declare - Loc : constant Source_Ptr := Sloc (N); - SCS : constant Boolean := - Get_Comes_From_Source_Default; - - begin - Set_Comes_From_Source_Default (False); - Lib_Unit := - Make_Compilation_Unit (Loc, - Context_Items => New_Copy_List (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)); - 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 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; - Save_C_Restrict : constant Save_Cunit_Boolean_Restrictions := - Cunit_Boolean_Restrictions_Save; - - begin - if not GNAT_Mode then - Style_Check := False; - end if; - - Semantics (Parent_Spec (Unit_Node)); - Version_Update (N, Parent_Spec (Unit_Node)); - Style_Check := Save_Style_Check; - Cunit_Boolean_Restrictions_Restore (Save_C_Restrict); - 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; - Save_C_Restrict : constant Save_Cunit_Boolean_Restrictions := - Cunit_Boolean_Restrictions_Save; - - 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; - - Style_Check := Save_Style_Check; - Cunit_Boolean_Restrictions_Restore (Save_C_Restrict); - 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 - Loc : constant Source_Ptr := Sloc (N); - L : constant List_Id := - Freeze_Entity (Cunit_Entity (Current_Sem_Unit), Loc); - 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) - - if Present (Library_Unit (Item)) then - Analyze (Item); - 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 of immediate " - & "ancestor not allowed", 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 a 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); - 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 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 - Unum := - Load_Unit - (Load_Name => Subunit_Name, - Required => False, - Subunit => True, - Error_Node => N); - - 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); - - -- 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 - -- specification. If there is one, 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; - - 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 - 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 - 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; - 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'); - Set_Has_Completion (Etype (Nam)); - 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 Expander_Active then - Insert_After (N, - Make_Assignment_Statement (Loc, - Name => - Make_Identifier (Loc, - 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 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 - - Save_Style_Check : constant Boolean := Opt.Style_Check; - Save_C_Restrict : constant Save_Cunit_Boolean_Restrictions := - Cunit_Boolean_Restrictions_Save; - - begin - U := Unit (Library_Unit (N)); - - -- 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 (Unit (Library_Unit (N))))) - 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 currently compiling the main unit and the main unit is itself - -- not an internal unit. We do not issue this message for implicit - -- with's generated by the compiler itself. - - if Implementation_Unit_Warnings - and then Current_Sem_Unit = Main_Unit - and then not Intunit - and then not Implicit_With (N) - and then not GNAT_Mode - 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)); - Error_Msg_F - ("\use of this unit is non-portable " & - "and version-dependent?", - Name (N)); - - elsif U_Kind = Ada_05_Unit - and then Ada_Version < Ada_05 - and then Warn_On_Ada_2005_Compatibility - then - Error_Msg_N ("& is an Ada 2005 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 - 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 - - -- Instantiation node is replaced with a wrapper package. Retrieve - -- the visible subprogram created by the instance from corresponding - -- attribute of the wrapper. - - E_Name := Related_Instance (Defining_Entity (U)); - - 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)); - end if; - - -- Restore style checks and restrictions - - Style_Check := Save_Style_Check; - Cunit_Boolean_Restrictions_Restore (Save_C_Restrict); - - -- 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); - - 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); - Set_Entity_With_Style_Check (Pref, Par_Name); - - Generate_Reference (Par_Name, Pref); - 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; - 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; - - Set_Entity_With_Style_Check (Pref, Par_Name); - Generate_Reference (Par_Name, Pref); - 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. - - 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; - Renaming : Entity_Id; - Result : Node_Id; - - begin - if Nkind (Nam) = N_Identifier then - - -- If the parent unit P in the name of the with_clause for P.Q - -- is a renaming of package R, then the entity of the parent is - -- set to R, but the identifier retains Chars (P) to be consistent - -- with the source (see details in lib-load). However, the - -- implicit_with_clause for the parent must make the entity for - -- P visible, because P.Q may be used as a prefix within the - -- current unit. The entity for P is the current_entity with that - -- name, because the package renaming declaration for it has just - -- been analyzed. Note that this case can only happen if P.Q has - -- already appeared in a previous with_clause in a related unit, - -- such as the library body of the current unit. - - if Chars (Nam) /= Chars (Entity (Nam)) then - Renaming := Current_Entity (Nam); - pragma Assert (Renamed_Entity (Renaming) = Entity (Nam)); - return New_Occurrence_Of (Renaming, Loc); - - else - return New_Occurrence_Of (Entity (Nam), Loc); - end if; - - 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 that 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; - - ----------------------------- - -- 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 with'ed 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 withs 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. - - 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)); - - 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). - - --------------------- - -- 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 not 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; 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; - - -- 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) - 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) - 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; - - -- All items other than Limited_With clauses are ignored (they were - -- installed separately early on by Install_Context_Clause). - - else - null; - end if; - - Next (Item); - end loop; - - -- Ada 2005 (AI-412): Examine the visible declarations of a package - -- spec, looking for incomplete subtype declarations of incomplete - -- types visible through a limited with clause. - - if Ada_Version >= Ada_05 - 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. - - E_Name := Defining_Entity (Lib_Unit); - - Set_Is_Child_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) - 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. - - elsif Private_Present (Item) then - Id := Entity (Name (Item)); - - if Is_Child_Unit (Id) then - Set_Is_Visible_Child_Unit (Id, False); - 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 Has_With_Clause - (C_Unit : Node_Id; - Pack : Entity_Id; - Is_Limited : Boolean := False) return Boolean; - -- Determine whether compilation unit C_Unit contains a with clause - -- for package Pack. Use flag Is_Limited to designate desired clause - -- kind. This is a subsidiary routine to Has_Limited_With_Clause. - - 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 -- - ------------------------- - - -- ??? misses pragma Import on subprograms - -- ??? misses pragma Import on renamed subprograms - - 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; - - 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 - - while Present (Decl) loop - - -- Subprogram that comes from source means body required - -- This is where a test for Import is missing ??? - - if Comes_From_Source (Decl) - and then (Nkind_In (Decl, N_Subprogram_Declaration, - N_Generic_Subprogram_Declaration)) - then - Set_Body_Required (Library_Unit (N)); - return; - - -- 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)); - 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_Generic_Subprogram_Declaration)) - then - Set_Body_Required (Library_Unit (N)); - - 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); - 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; - 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; - - --------------------- - -- Has_With_Clause -- - --------------------- - - function Has_With_Clause - (C_Unit : Node_Id; - Pack : Entity_Id; - Is_Limited : Boolean := False) return Boolean - is - Item : Node_Id; - Nam : Entity_Id; - - begin - if Present (Context_Items (C_Unit)) then - Item := First (Context_Items (C_Unit)); - while Present (Item) loop - if Nkind (Item) = N_With_Clause then - - -- Retrieve the entity of the imported compilation unit - - if Nkind (Name (Item)) = N_Selected_Component then - Nam := Entity (Selector_Name (Name (Item))); - else - Nam := Entity (Name (Item)); - end if; - - if Nam = Pack - and then - ((Is_Limited and then Limited_Present (Item)) - or else - (not Is_Limited and then not Limited_Present (Item))) - then - return True; - end if; - end if; - - Next (Item); - end loop; - end if; - - return False; - end Has_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 Present (Library_Unit (Aux_Unit)) 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 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 - return; - 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). - - Set_Entity (Nam, Ent); - - Nam := Prefix (Nam); - Ent := Scope (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 - 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_05 - 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; - - ----------------------- - -- 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) 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; - - Semantics (Cunit (Unum)); - 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); - -- Set basic attributes of tagged type T, including its class_wide type. - -- The parameters Loc, Scope are used to decorate the class_wide type. - - 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 - - ------------------------------ - -- 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) - 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 := Make_Defining_Identifier (Loc, New_Internal_Name ('S')); - - -- 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)); - - -- 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_Defining_Identifier (Sloc_Value, - Chars => New_Internal_Name (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; - - ----------------- - -- 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); - 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); - - 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); - 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); - - 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); - 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; - - -- 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_Defining_Identifier (Sloc (N), - Chars => New_Internal_Name (Id_Char => '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 (E) = E_Generic_Function - or else Ekind (E) = 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 (Unit_Name) = E_Generic_Procedure - or else Ekind (Unit_Name) = 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 - -- Handle incomplete types of the real view. For this purpose - -- we traverse the list of visible entities to look for an - -- incomplete type in the real-view associated with Lim_Typ. - - E := First_Entity (P); - while Present (E) and then E /= First_Private_Entity (P) loop - exit when Ekind (E) = E_Incomplete_Type - and then Present (Full_View (E)) - and then Full_View (E) = Lim_Typ; - - Next_Entity (E); - end loop; - - -- If the previous search was not successful then the entity - -- to be restored in the homonym list is the non-limited view - - if E = First_Private_Entity (P) then - E := Non_Limited_View (Lim_Typ); - end if; - - 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; - - -- We must also set the next homonym entity of the real entity - -- to handle the case in which the next homonym was a shadow - -- entity. - - Set_Homonym (E, Homonym (Lim_Typ)); - 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; |