X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fada%2Fsem_util.adb;h=82dca5662a30dd4d25856a628d5169b577718301;hb=169337519eece470dd1e178a4356030a6c845b37;hp=ab963458c9955ea40e078bedd684f8ce68bf31ed;hpb=9f373bb8832c6f7b52c057ab7db0f09433c9f222;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb index ab963458c99..82dca5662a3 100644 --- a/gcc/ada/sem_util.adb +++ b/gcc/ada/sem_util.adb @@ -6,18 +6,17 @@ -- -- -- B o d y -- -- -- --- Copyright (C) 1992-2005, Free Software Foundation, Inc. -- +-- 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 2, or (at your option) any later ver- -- +-- 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 COPYING. If not, write -- --- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- --- MA 02111-1307, USA. -- +-- 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. -- @@ -30,28 +29,27 @@ with Checks; use Checks; with Debug; use Debug; with Errout; use Errout; with Elists; use Elists; +with Exp_Disp; use Exp_Disp; with Exp_Tss; use Exp_Tss; with Exp_Util; use Exp_Util; with Fname; use Fname; with Freeze; use Freeze; with Lib; use Lib; with Lib.Xref; use Lib.Xref; -with Namet; use Namet; with Nlists; use Nlists; -with Nmake; use Nmake; with Output; use Output; with Opt; use Opt; with Rtsfind; use Rtsfind; with Scans; use Scans; with Scn; use Scn; with Sem; use Sem; +with Sem_Attr; use Sem_Attr; with Sem_Ch8; use Sem_Ch8; with Sem_Eval; use Sem_Eval; with Sem_Res; use Sem_Res; with Sem_Type; use Sem_Type; with Sinfo; use Sinfo; with Sinput; use Sinput; -with Snames; use Snames; with Stand; use Stand; with Style; with Stringt; use Stringt; @@ -84,6 +82,75 @@ package body Sem_Util is -- T is a derived tagged type. Check whether the type extension is null. -- If the parent type is fully initialized, T can be treated as such. + ------------------------------ + -- Abstract_Interface_List -- + ------------------------------ + + function Abstract_Interface_List (Typ : Entity_Id) return List_Id is + Nod : Node_Id; + + begin + if Is_Concurrent_Type (Typ) then + + -- If we are dealing with a synchronized subtype, go to the base + -- type, whose declaration has the interface list. + + -- Shouldn't this be Declaration_Node??? + + Nod := Parent (Base_Type (Typ)); + + if Nkind (Nod) = N_Full_Type_Declaration then + return Empty_List; + end if; + + elsif Ekind (Typ) = E_Record_Type_With_Private then + if Nkind (Parent (Typ)) = N_Full_Type_Declaration then + Nod := Type_Definition (Parent (Typ)); + + elsif Nkind (Parent (Typ)) = N_Private_Type_Declaration then + if Present (Full_View (Typ)) then + Nod := Type_Definition (Parent (Full_View (Typ))); + + -- If the full-view is not available we cannot do anything else + -- here (the source has errors). + + else + return Empty_List; + end if; + + -- Support for generic formals with interfaces is still missing ??? + + elsif Nkind (Parent (Typ)) = N_Formal_Type_Declaration then + return Empty_List; + + else + pragma Assert + (Nkind (Parent (Typ)) = N_Private_Extension_Declaration); + Nod := Parent (Typ); + end if; + + elsif Ekind (Typ) = E_Record_Subtype then + Nod := Type_Definition (Parent (Etype (Typ))); + + elsif Ekind (Typ) = E_Record_Subtype_With_Private then + + -- Recurse, because parent may still be a private extension. Also + -- note that the full view of the subtype or the full view of its + -- base type may (both) be unavailable. + + return Abstract_Interface_List (Etype (Typ)); + + else pragma Assert ((Ekind (Typ)) = E_Record_Type); + if Nkind (Parent (Typ)) = N_Formal_Type_Declaration then + Nod := Formal_Type_Definition (Parent (Typ)); + else + Nod := Type_Definition (Parent (Typ)); + end if; + end if; + + return Interface_List (Nod); + end Abstract_Interface_List; + -------------------------------- -- Add_Access_Type_To_Process -- -------------------------------- @@ -103,6 +170,22 @@ package body Sem_Util is Append_Elmt (A, L); end Add_Access_Type_To_Process; + ---------------------------- + -- Add_Global_Declaration -- + ---------------------------- + + procedure Add_Global_Declaration (N : Node_Id) is + Aux_Node : constant Node_Id := Aux_Decls_Node (Cunit (Current_Sem_Unit)); + + begin + if No (Declarations (Aux_Node)) then + Set_Declarations (Aux_Node, New_List); + end if; + + Append_To (Declarations (Aux_Node), N); + Analyze (N); + end Add_Global_Declaration; + ----------------------- -- Alignment_In_Bits -- ----------------------- @@ -126,8 +209,10 @@ package body Sem_Util is Rep : Boolean := True; Warn : Boolean := False) is - Stat : constant Boolean := Is_Static_Expression (N); - Rtyp : Entity_Id; + Stat : constant Boolean := Is_Static_Expression (N); + R_Stat : constant Node_Id := + Make_Raise_Constraint_Error (Sloc (N), Reason => Reason); + Rtyp : Entity_Id; begin if No (Typ) then @@ -136,8 +221,8 @@ package body Sem_Util is Rtyp := Typ; end if; - Discard_Node ( - Compile_Time_Constraint_Error (N, Msg, Ent, Loc, Warn => Warn)); + Discard_Node + (Compile_Time_Constraint_Error (N, Msg, Ent, Loc, Warn => Warn)); if not Rep then return; @@ -146,10 +231,9 @@ package body Sem_Util is -- Now we replace the node by an N_Raise_Constraint_Error node -- This does not need reanalyzing, so set it as analyzed now. - Rewrite (N, - Make_Raise_Constraint_Error (Sloc (N), - Reason => Reason)); + Rewrite (N, R_Stat); Set_Analyzed (N, True); + Set_Etype (N, Rtyp); Set_Raises_Constraint_Error (N); @@ -170,9 +254,9 @@ package body Sem_Util is (T : Entity_Id; N : Node_Or_Entity_Id) return Node_Id is - Obj : Node_Id; + Loc : Source_Ptr; + -- Normally Sloc (N), but may point to corresponding body in some cases - Loc : constant Source_Ptr := Sloc (N); Constraints : List_Id; Decl : Node_Id; Discr : Entity_Id; @@ -180,23 +264,43 @@ package body Sem_Util is Lo : Node_Id; Subt : Entity_Id; Disc_Type : Entity_Id; + Obj : Node_Id; begin + Loc := Sloc (N); + if Nkind (N) = N_Defining_Identifier then Obj := New_Reference_To (N, Loc); + + -- If this is a formal parameter of a subprogram declaration, and + -- we are compiling the body, we want the declaration for the + -- actual subtype to carry the source position of the body, to + -- prevent anomalies in gdb when stepping through the code. + + if Is_Formal (N) then + declare + Decl : constant Node_Id := Unit_Declaration_Node (Scope (N)); + begin + if Nkind (Decl) = N_Subprogram_Declaration + and then Present (Corresponding_Body (Decl)) + then + Loc := Sloc (Corresponding_Body (Decl)); + end if; + end; + end if; + else Obj := N; end if; if Is_Array_Type (T) then Constraints := New_List; - for J in 1 .. Number_Dimensions (T) loop - -- Build an array subtype declaration with the nominal - -- subtype and the bounds of the actual. Add the declaration - -- in front of the local declarations for the subprogram, for - -- analysis before any reference to the formal in the body. + -- Build an array subtype declaration with the nominal subtype and + -- the bounds of the actual. Add the declaration in front of the + -- local declarations for the subprogram, for analysis before any + -- reference to the formal in the body. Lo := Make_Attribute_Reference (Loc, @@ -227,18 +331,25 @@ package body Sem_Util is else Constraints := New_List; - if Is_Private_Type (T) and then No (Full_View (T)) then + -- Type T is a generic derived type, inherit the discriminants from + -- the parent type. + + if Is_Private_Type (T) + and then No (Full_View (T)) - -- Type is a generic derived type. Inherit discriminants from - -- Parent type. + -- T was flagged as an error if it was declared as a formal + -- derived type with known discriminants. In this case there + -- is no need to look at the parent type since T already carries + -- its own discriminants. + and then not Error_Posted (T) + then Disc_Type := Etype (Base_Type (T)); else Disc_Type := T; end if; Discr := First_Discriminant (Disc_Type); - while Present (Discr) loop Append_To (Constraints, Make_Selected_Component (Loc, @@ -361,7 +472,6 @@ package body Sem_Util is begin D := First_Elmt (Discriminant_Constraint (Deaccessed_T)); while Present (D) loop - if Denotes_Discriminant (Node (D)) then D_Val := Make_Selected_Component (Loc, Prefix => New_Copy_Tree (P), @@ -381,9 +491,13 @@ package body Sem_Util is -- Start of processing for Build_Actual_Subtype_Of_Component begin - if In_Default_Expression then + -- Why the test for Spec_Expression mode here??? + + if In_Spec_Expression then return Empty; + -- More comments for the rest of this body would be good ??? + elsif Nkind (N) = N_Explicit_Dereference then if Is_Composite_Type (T) and then not Is_Constrained (T) @@ -415,17 +529,17 @@ package body Sem_Util is if Ekind (Deaccessed_T) = E_Array_Subtype then Id := First_Index (Deaccessed_T); - while Present (Id) loop Indx_Type := Underlying_Type (Etype (Id)); - if Denotes_Discriminant (Type_Low_Bound (Indx_Type)) or else + if Denotes_Discriminant (Type_Low_Bound (Indx_Type)) + or else Denotes_Discriminant (Type_High_Bound (Indx_Type)) then Remove_Side_Effects (P); return - Build_Component_Subtype ( - Build_Actual_Array_Constraint, Loc, Base_Type (T)); + Build_Component_Subtype + (Build_Actual_Array_Constraint, Loc, Base_Type (T)); end if; Next_Index (Id); @@ -437,7 +551,6 @@ package body Sem_Util is then D := First_Elmt (Discriminant_Constraint (Deaccessed_T)); while Present (D) loop - if Denotes_Discriminant (Node (D)) then Remove_Side_Effects (P); return @@ -492,6 +605,59 @@ package body Sem_Util is return Decl; end Build_Component_Subtype; + --------------------------- + -- Build_Default_Subtype -- + --------------------------- + + function Build_Default_Subtype + (T : Entity_Id; + N : Node_Id) return Entity_Id + is + Loc : constant Source_Ptr := Sloc (N); + Disc : Entity_Id; + + begin + if not Has_Discriminants (T) or else Is_Constrained (T) then + return T; + end if; + + Disc := First_Discriminant (T); + + if No (Discriminant_Default_Value (Disc)) then + return T; + end if; + + declare + Act : constant Entity_Id := + Make_Defining_Identifier (Loc, + Chars => New_Internal_Name ('S')); + + Constraints : constant List_Id := New_List; + Decl : Node_Id; + + begin + while Present (Disc) loop + Append_To (Constraints, + New_Copy_Tree (Discriminant_Default_Value (Disc))); + Next_Discriminant (Disc); + end loop; + + Decl := + Make_Subtype_Declaration (Loc, + Defining_Identifier => Act, + Subtype_Indication => + Make_Subtype_Indication (Loc, + Subtype_Mark => New_Occurrence_Of (T, Loc), + Constraint => + Make_Index_Or_Discriminant_Constraint (Loc, + Constraints => Constraints))); + + Insert_Action (N, Decl); + Analyze (Decl); + return Act; + end; + end Build_Default_Subtype; + -------------------------------------------- -- Build_Discriminal_Subtype_Of_Component -- -------------------------------------------- @@ -583,7 +749,6 @@ package body Sem_Util is begin if Ekind (T) = E_Array_Subtype then Id := First_Index (T); - while Present (Id) loop if Denotes_Discriminant (Type_Low_Bound (Etype (Id))) or else Denotes_Discriminant (Type_High_Bound (Etype (Id))) @@ -620,11 +785,39 @@ package body Sem_Util is ------------------------------ procedure Build_Elaboration_Entity (N : Node_Id; Spec_Id : Entity_Id) is - Loc : constant Source_Ptr := Sloc (N); - Unum : constant Unit_Number_Type := Get_Source_Unit (Loc); - Decl : Node_Id; - P : Natural; - Elab_Ent : Entity_Id; + Loc : constant Source_Ptr := Sloc (N); + Decl : Node_Id; + Elab_Ent : Entity_Id; + + procedure Set_Package_Name (Ent : Entity_Id); + -- Given an entity, sets the fully qualified name of the entity in + -- Name_Buffer, with components separated by double underscores. This + -- is a recursive routine that climbs the scope chain to Standard. + + ---------------------- + -- Set_Package_Name -- + ---------------------- + + procedure Set_Package_Name (Ent : Entity_Id) is + begin + if Scope (Ent) /= Standard_Standard then + Set_Package_Name (Scope (Ent)); + + declare + Nam : constant String := Get_Name_String (Chars (Ent)); + begin + Name_Buffer (Name_Len + 1) := '_'; + Name_Buffer (Name_Len + 2) := '_'; + Name_Buffer (Name_Len + 3 .. Name_Len + Nam'Length + 2) := Nam; + Name_Len := Name_Len + Nam'Length + 2; + end; + + else + Get_Name_String (Chars (Ent)); + end if; + end Set_Package_Name; + + -- Start of processing for Build_Elaboration_Entity begin -- Ignore if already constructed @@ -633,33 +826,18 @@ package body Sem_Util is return; end if; - -- Construct name of elaboration entity as xxx_E, where xxx - -- is the unit name with dots replaced by double underscore. - -- We have to manually construct this name, since it will - -- be elaborated in the outer scope, and thus will not have - -- the unit name automatically prepended. - - Get_Name_String (Unit_Name (Unum)); - - -- Replace the %s by _E + -- Construct name of elaboration entity as xxx_E, where xxx is the unit + -- name with dots replaced by double underscore. We have to manually + -- construct this name, since it will be elaborated in the outer scope, + -- and thus will not have the unit name automatically prepended. - Name_Buffer (Name_Len - 1 .. Name_Len) := "_E"; + Set_Package_Name (Spec_Id); - -- Replace dots by double underscore + -- Append _E - P := 2; - while P < Name_Len - 2 loop - if Name_Buffer (P) = '.' then - Name_Buffer (P + 2 .. Name_Len + 1) := - Name_Buffer (P + 1 .. Name_Len); - Name_Len := Name_Len + 1; - Name_Buffer (P) := '_'; - Name_Buffer (P + 1) := '_'; - P := P + 3; - else - P := P + 1; - end if; - end loop; + Name_Buffer (Name_Len + 1) := '_'; + Name_Buffer (Name_Len + 2) := 'E'; + Name_Len := Name_Len + 2; -- Create elaboration flag @@ -667,10 +845,6 @@ package body Sem_Util is Make_Defining_Identifier (Loc, Chars => Name_Find); Set_Elaboration_Entity (Spec_Id, Elab_Ent); - if No (Declarations (Aux_Decls_Node (N))) then - Set_Declarations (Aux_Decls_Node (N), New_List); - end if; - Decl := Make_Object_Declaration (Loc, Defining_Identifier => Elab_Ent, @@ -679,14 +853,17 @@ package body Sem_Util is Expression => New_Occurrence_Of (Standard_False, Loc)); - Append_To (Declarations (Aux_Decls_Node (N)), Decl); - Analyze (Decl); + Push_Scope (Standard_Standard); + Add_Global_Declaration (Decl); + Pop_Scope; - -- Reset True_Constant indication, since we will indeed - -- assign a value to the variable in the binder main. + -- Reset True_Constant indication, since we will indeed assign a value + -- to the variable in the binder main. We also kill the Current_Value + -- and Last_Assignment fields for the same reason. Set_Is_True_Constant (Elab_Ent, False); Set_Current_Value (Elab_Ent, Empty); + Set_Last_Assignment (Elab_Ent, Empty); -- We do not want any further qualification of the name (if we did -- not do this, we would pick up the name of the generic package @@ -731,9 +908,10 @@ package body Sem_Util is else declare - N : Node_Id := First (Expressions (Expr)); + N : Node_Id; begin + N := First (Expressions (Expr)); while Present (N) loop if Cannot_Raise_Constraint_Error (N) then Next (N); @@ -841,11 +1019,12 @@ package body Sem_Util is ("premature usage of incomplete}", N, First_Subtype (T)); end if; + -- Need comments for these tests ??? + elsif Has_Private_Component (T) and then not Is_Generic_Type (Root_Type (T)) - and then not In_Default_Expression + and then not In_Spec_Expression then - -- Special case: if T is the anonymous type created for a single -- task or protected object, use the name of the source object. @@ -863,13 +1042,56 @@ package body Sem_Util is end if; end Check_Fully_Declared; + ------------------------- + -- Check_Nested_Access -- + ------------------------- + + procedure Check_Nested_Access (Ent : Entity_Id) is + Scop : constant Entity_Id := Current_Scope; + Current_Subp : Entity_Id; + Enclosing : Entity_Id; + + begin + -- Currently only enabled for VM back-ends for efficiency, should we + -- enable it more systematically ??? + + -- Check for Is_Imported needs commenting below ??? + + if VM_Target /= No_VM + and then (Ekind (Ent) = E_Variable + or else + Ekind (Ent) = E_Constant + or else + Ekind (Ent) = E_Loop_Parameter) + and then Scope (Ent) /= Empty + and then not Is_Library_Level_Entity (Ent) + and then not Is_Imported (Ent) + then + if Is_Subprogram (Scop) + or else Is_Generic_Subprogram (Scop) + or else Is_Entry (Scop) + then + Current_Subp := Scop; + else + Current_Subp := Current_Subprogram; + end if; + + Enclosing := Enclosing_Subprogram (Ent); + + if Enclosing /= Empty + and then Enclosing /= Current_Subp + then + Set_Has_Up_Level_Access (Ent, True); + end if; + end if; + end Check_Nested_Access; + ------------------------------------------ -- Check_Potentially_Blocking_Operation -- ------------------------------------------ procedure Check_Potentially_Blocking_Operation (N : Node_Id) is - S : Entity_Id; - + S : Entity_Id; begin -- N is one of the potentially blocking operations listed in 9.5.1(8). -- When pragma Detect_Blocking is active, the run time will raise @@ -894,6 +1116,117 @@ package body Sem_Util is end loop; end Check_Potentially_Blocking_Operation; + ------------------------------ + -- Check_Unprotected_Access -- + ------------------------------ + + procedure Check_Unprotected_Access + (Context : Node_Id; + Expr : Node_Id) + is + Cont_Encl_Typ : Entity_Id; + Pref_Encl_Typ : Entity_Id; + + function Enclosing_Protected_Type (Obj : Node_Id) return Entity_Id; + -- Check whether Obj is a private component of a protected object. + -- Return the protected type where the component resides, Empty + -- otherwise. + + function Is_Public_Operation return Boolean; + -- Verify that the enclosing operation is callable from outside the + -- protected object, to minimize false positives. + + ------------------------------ + -- Enclosing_Protected_Type -- + ------------------------------ + + function Enclosing_Protected_Type (Obj : Node_Id) return Entity_Id is + begin + if Is_Entity_Name (Obj) then + declare + Ent : Entity_Id := Entity (Obj); + + begin + -- The object can be a renaming of a private component, use + -- the original record component. + + if Is_Prival (Ent) then + Ent := Prival_Link (Ent); + end if; + + if Is_Protected_Type (Scope (Ent)) then + return Scope (Ent); + end if; + end; + end if; + + -- For indexed and selected components, recursively check the prefix + + if Nkind_In (Obj, N_Indexed_Component, N_Selected_Component) then + return Enclosing_Protected_Type (Prefix (Obj)); + + -- The object does not denote a protected component + + else + return Empty; + end if; + end Enclosing_Protected_Type; + + ------------------------- + -- Is_Public_Operation -- + ------------------------- + + function Is_Public_Operation return Boolean is + S : Entity_Id; + E : Entity_Id; + + begin + S := Current_Scope; + while Present (S) + and then S /= Pref_Encl_Typ + loop + if Scope (S) = Pref_Encl_Typ then + E := First_Entity (Pref_Encl_Typ); + while Present (E) + and then E /= First_Private_Entity (Pref_Encl_Typ) + loop + if E = S then + return True; + end if; + Next_Entity (E); + end loop; + end if; + + S := Scope (S); + end loop; + + return False; + end Is_Public_Operation; + + -- Start of processing for Check_Unprotected_Access + + begin + if Nkind (Expr) = N_Attribute_Reference + and then Attribute_Name (Expr) = Name_Unchecked_Access + then + Cont_Encl_Typ := Enclosing_Protected_Type (Context); + Pref_Encl_Typ := Enclosing_Protected_Type (Prefix (Expr)); + + -- Check whether we are trying to export a protected component to a + -- context with an equal or lower access level. + + if Present (Pref_Encl_Typ) + and then No (Cont_Encl_Typ) + and then Is_Public_Operation + and then Scope_Depth (Pref_Encl_Typ) >= + Object_Access_Level (Context) + then + Error_Msg_N + ("?possible unprotected access to protected data", Expr); + end if; + end if; + end Check_Unprotected_Access; + --------------- -- Check_VMS -- --------------- @@ -906,91 +1239,343 @@ package body Sem_Util is end if; end Check_VMS; - ---------------------------------- - -- Collect_Primitive_Operations -- - ---------------------------------- + ------------------------ + -- Collect_Interfaces -- + ------------------------ - function Collect_Primitive_Operations (T : Entity_Id) return Elist_Id is - B_Type : constant Entity_Id := Base_Type (T); - B_Decl : constant Node_Id := Original_Node (Parent (B_Type)); - B_Scope : Entity_Id := Scope (B_Type); - Op_List : Elist_Id; - Formal : Entity_Id; - Is_Prim : Boolean; - Formal_Derived : Boolean := False; - Id : Entity_Id; + procedure Collect_Interfaces + (T : Entity_Id; + Ifaces_List : out Elist_Id; + Exclude_Parents : Boolean := False; + Use_Full_View : Boolean := True) + is + procedure Collect (Typ : Entity_Id); + -- Subsidiary subprogram used to traverse the whole list + -- of directly and indirectly implemented interfaces - begin - -- For tagged types, the primitive operations are collected as they - -- are declared, and held in an explicit list which is simply returned. + ------------- + -- Collect -- + ------------- - if Is_Tagged_Type (B_Type) then - return Primitive_Operations (B_Type); + procedure Collect (Typ : Entity_Id) is + Ancestor : Entity_Id; + Full_T : Entity_Id; + Id : Node_Id; + Iface : Entity_Id; - -- An untagged generic type that is a derived type inherits the - -- primitive operations of its parent type. Other formal types only - -- have predefined operators, which are not explicitly represented. + begin + Full_T := Typ; - elsif Is_Generic_Type (B_Type) then - if Nkind (B_Decl) = N_Formal_Type_Declaration - and then Nkind (Formal_Type_Definition (B_Decl)) - = N_Formal_Derived_Type_Definition + -- Handle private types + + if Use_Full_View + and then Is_Private_Type (Typ) + and then Present (Full_View (Typ)) then - Formal_Derived := True; - else - return New_Elmt_List; + Full_T := Full_View (Typ); end if; - end if; - - Op_List := New_Elmt_List; - - if B_Scope = Standard_Standard then - if B_Type = Standard_String then - Append_Elmt (Standard_Op_Concat, Op_List); - elsif B_Type = Standard_Wide_String then - Append_Elmt (Standard_Op_Concatw, Op_List); + -- Include the ancestor if we are generating the whole list of + -- abstract interfaces. - else - null; - end if; + if Etype (Full_T) /= Typ - elsif (Is_Package (B_Scope) - and then Nkind ( - Parent (Declaration_Node (First_Subtype (T)))) - /= N_Package_Body) + -- Protect the frontend against wrong sources. For example: - or else Is_Derived_Type (B_Type) - then - -- The primitive operations appear after the base type, except - -- if the derivation happens within the private part of B_Scope - -- and the type is a private type, in which case both the type - -- and some primitive operations may appear before the base - -- type, and the list of candidates starts after the type. + -- package P is + -- type A is tagged null record; + -- type B is new A with private; + -- type C is new A with private; + -- private + -- type B is new C with null record; + -- type C is new B with null record; + -- end P; - if In_Open_Scopes (B_Scope) - and then Scope (T) = B_Scope - and then In_Private_Part (B_Scope) + and then Etype (Full_T) /= T then - Id := Next_Entity (T); - else - Id := Next_Entity (B_Type); + Ancestor := Etype (Full_T); + Collect (Ancestor); + + if Is_Interface (Ancestor) + and then not Exclude_Parents + then + Append_Unique_Elmt (Ancestor, Ifaces_List); + end if; end if; - while Present (Id) loop + -- Traverse the graph of ancestor interfaces - -- Note that generic formal subprograms are not - -- considered to be primitive operations and thus - -- are never inherited. + if Is_Non_Empty_List (Abstract_Interface_List (Full_T)) then + Id := First (Abstract_Interface_List (Full_T)); + while Present (Id) loop + Iface := Etype (Id); - if Is_Overloadable (Id) - and then Nkind (Parent (Parent (Id))) - not in N_Formal_Subprogram_Declaration - then - Is_Prim := False; + -- Protect against wrong uses. For example: + -- type I is interface; + -- type O is tagged null record; + -- type Wrong is new I and O with null record; -- ERROR - if Base_Type (Etype (Id)) = B_Type then - Is_Prim := True; + if Is_Interface (Iface) then + if Exclude_Parents + and then Etype (T) /= T + and then Interface_Present_In_Ancestor (Etype (T), Iface) + then + null; + else + Collect (Iface); + Append_Unique_Elmt (Iface, Ifaces_List); + end if; + end if; + + Next (Id); + end loop; + end if; + end Collect; + + -- Start of processing for Collect_Interfaces + + begin + pragma Assert (Is_Tagged_Type (T) or else Is_Concurrent_Type (T)); + Ifaces_List := New_Elmt_List; + Collect (T); + end Collect_Interfaces; + + ---------------------------------- + -- Collect_Interface_Components -- + ---------------------------------- + + procedure Collect_Interface_Components + (Tagged_Type : Entity_Id; + Components_List : out Elist_Id) + is + procedure Collect (Typ : Entity_Id); + -- Subsidiary subprogram used to climb to the parents + + ------------- + -- Collect -- + ------------- + + procedure Collect (Typ : Entity_Id) is + Tag_Comp : Entity_Id; + + begin + if Etype (Typ) /= Typ + + -- Protect the frontend against wrong sources. For example: + + -- package P is + -- type A is tagged null record; + -- type B is new A with private; + -- type C is new A with private; + -- private + -- type B is new C with null record; + -- type C is new B with null record; + -- end P; + + and then Etype (Typ) /= Tagged_Type + then + Collect (Etype (Typ)); + end if; + + -- Collect the components containing tags of secondary dispatch + -- tables. + + Tag_Comp := Next_Tag_Component (First_Tag_Component (Typ)); + while Present (Tag_Comp) loop + pragma Assert (Present (Related_Type (Tag_Comp))); + Append_Elmt (Tag_Comp, Components_List); + + Tag_Comp := Next_Tag_Component (Tag_Comp); + end loop; + end Collect; + + -- Start of processing for Collect_Interface_Components + + begin + pragma Assert (Ekind (Tagged_Type) = E_Record_Type + and then Is_Tagged_Type (Tagged_Type)); + + Components_List := New_Elmt_List; + Collect (Tagged_Type); + end Collect_Interface_Components; + + ----------------------------- + -- Collect_Interfaces_Info -- + ----------------------------- + + procedure Collect_Interfaces_Info + (T : Entity_Id; + Ifaces_List : out Elist_Id; + Components_List : out Elist_Id; + Tags_List : out Elist_Id) + is + Comps_List : Elist_Id; + Comp_Elmt : Elmt_Id; + Comp_Iface : Entity_Id; + Iface_Elmt : Elmt_Id; + Iface : Entity_Id; + + function Search_Tag (Iface : Entity_Id) return Entity_Id; + -- Search for the secondary tag associated with the interface type + -- Iface that is implemented by T. + + ---------------- + -- Search_Tag -- + ---------------- + + function Search_Tag (Iface : Entity_Id) return Entity_Id is + ADT : Elmt_Id; + + begin + ADT := Next_Elmt (Next_Elmt (First_Elmt (Access_Disp_Table (T)))); + while Present (ADT) + and then Ekind (Node (ADT)) = E_Constant + and then Related_Type (Node (ADT)) /= Iface + loop + -- Skip the secondary dispatch tables of Iface + + Next_Elmt (ADT); + Next_Elmt (ADT); + Next_Elmt (ADT); + Next_Elmt (ADT); + end loop; + + pragma Assert (Ekind (Node (ADT)) = E_Constant); + return Node (ADT); + end Search_Tag; + + -- Start of processing for Collect_Interfaces_Info + + begin + Collect_Interfaces (T, Ifaces_List); + Collect_Interface_Components (T, Comps_List); + + -- Search for the record component and tag associated with each + -- interface type of T. + + Components_List := New_Elmt_List; + Tags_List := New_Elmt_List; + + Iface_Elmt := First_Elmt (Ifaces_List); + while Present (Iface_Elmt) loop + Iface := Node (Iface_Elmt); + + -- Associate the primary tag component and the primary dispatch table + -- with all the interfaces that are parents of T + + if Is_Ancestor (Iface, T) then + Append_Elmt (First_Tag_Component (T), Components_List); + Append_Elmt (Node (First_Elmt (Access_Disp_Table (T))), Tags_List); + + -- Otherwise search for the tag component and secondary dispatch + -- table of Iface + + else + Comp_Elmt := First_Elmt (Comps_List); + while Present (Comp_Elmt) loop + Comp_Iface := Related_Type (Node (Comp_Elmt)); + + if Comp_Iface = Iface + or else Is_Ancestor (Iface, Comp_Iface) + then + Append_Elmt (Node (Comp_Elmt), Components_List); + Append_Elmt (Search_Tag (Comp_Iface), Tags_List); + exit; + end if; + + Next_Elmt (Comp_Elmt); + end loop; + pragma Assert (Present (Comp_Elmt)); + end if; + + Next_Elmt (Iface_Elmt); + end loop; + end Collect_Interfaces_Info; + + ---------------------------------- + -- Collect_Primitive_Operations -- + ---------------------------------- + + function Collect_Primitive_Operations (T : Entity_Id) return Elist_Id is + B_Type : constant Entity_Id := Base_Type (T); + B_Decl : constant Node_Id := Original_Node (Parent (B_Type)); + B_Scope : Entity_Id := Scope (B_Type); + Op_List : Elist_Id; + Formal : Entity_Id; + Is_Prim : Boolean; + Formal_Derived : Boolean := False; + Id : Entity_Id; + + begin + -- For tagged types, the primitive operations are collected as they + -- are declared, and held in an explicit list which is simply returned. + + if Is_Tagged_Type (B_Type) then + return Primitive_Operations (B_Type); + + -- An untagged generic type that is a derived type inherits the + -- primitive operations of its parent type. Other formal types only + -- have predefined operators, which are not explicitly represented. + + elsif Is_Generic_Type (B_Type) then + if Nkind (B_Decl) = N_Formal_Type_Declaration + and then Nkind (Formal_Type_Definition (B_Decl)) + = N_Formal_Derived_Type_Definition + then + Formal_Derived := True; + else + return New_Elmt_List; + end if; + end if; + + Op_List := New_Elmt_List; + + if B_Scope = Standard_Standard then + if B_Type = Standard_String then + Append_Elmt (Standard_Op_Concat, Op_List); + + elsif B_Type = Standard_Wide_String then + Append_Elmt (Standard_Op_Concatw, Op_List); + + else + null; + end if; + + elsif (Is_Package_Or_Generic_Package (B_Scope) + and then + Nkind (Parent (Declaration_Node (First_Subtype (T)))) /= + N_Package_Body) + or else Is_Derived_Type (B_Type) + then + -- The primitive operations appear after the base type, except + -- if the derivation happens within the private part of B_Scope + -- and the type is a private type, in which case both the type + -- and some primitive operations may appear before the base + -- type, and the list of candidates starts after the type. + + if In_Open_Scopes (B_Scope) + and then Scope (T) = B_Scope + and then In_Private_Part (B_Scope) + then + Id := Next_Entity (T); + else + Id := Next_Entity (B_Type); + end if; + + while Present (Id) loop + + -- Note that generic formal subprograms are not + -- considered to be primitive operations and thus + -- are never inherited. + + if Is_Overloadable (Id) + and then Nkind (Parent (Parent (Id))) + not in N_Formal_Subprogram_Declaration + then + Is_Prim := False; + + if Base_Type (Etype (Id)) = B_Type then + Is_Prim := True; else Formal := First_Formal (Id); while Present (Formal) loop @@ -1050,12 +1635,15 @@ package body Sem_Util is Msg : String; Ent : Entity_Id := Empty; Loc : Source_Ptr := No_Location; - Warn : Boolean := False) return Node_Id + Warn : Boolean := False) return Node_Id is Msgc : String (1 .. Msg'Length + 2); + -- Copy of message, with room for possible ? and ! at end + Msgl : Natural; Wmsg : Boolean; P : Node_Id; + OldP : Node_Id; Msgs : Boolean; Eloc : Source_Ptr; @@ -1074,15 +1662,12 @@ package body Sem_Util is Eloc := Sloc (N); end if; - -- Make all such messages unconditional - Msgc (1 .. Msg'Length) := Msg; - Msgc (Msg'Length + 1) := '!'; - Msgl := Msg'Length + 1; + Msgl := Msg'Length; -- Message is a warning, even in Ada 95 case - if Msg (Msg'Length) = '?' then + if Msg (Msg'Last) = '?' then Wmsg := True; -- In Ada 83, all messages are warnings. In the private part and @@ -1102,36 +1687,86 @@ package body Sem_Util is Wmsg := True; -- Otherwise we have a real error message (Ada 95 static case) + -- and we make this an unconditional message. Note that in the + -- warning case we do not make the message unconditional, it seems + -- quite reasonable to delete messages like this (about exceptions + -- that will be raised) in dead code. else Wmsg := False; + Msgl := Msgl + 1; + Msgc (Msgl) := '!'; end if; -- Should we generate a warning? The answer is not quite yes. The -- very annoying exception occurs in the case of a short circuit -- operator where the left operand is static and decisive. Climb - -- parents to see if that is the case we have here. + -- parents to see if that is the case we have here. Conditional + -- expressions with decisive conditions are a similar situation. Msgs := True; P := N; - loop + OldP := P; P := Parent (P); - if (Nkind (P) = N_And_Then - and then Compile_Time_Known_Value (Left_Opnd (P)) - and then Is_False (Expr_Value (Left_Opnd (P)))) - or else (Nkind (P) = N_Or_Else - and then Compile_Time_Known_Value (Left_Opnd (P)) - and then Is_True (Expr_Value (Left_Opnd (P)))) + -- And then with False as left operand + + if Nkind (P) = N_And_Then + and then Compile_Time_Known_Value (Left_Opnd (P)) + and then Is_False (Expr_Value (Left_Opnd (P))) + then + Msgs := False; + exit; + + -- OR ELSE with True as left operand + + elsif Nkind (P) = N_Or_Else + and then Compile_Time_Known_Value (Left_Opnd (P)) + and then Is_True (Expr_Value (Left_Opnd (P))) then Msgs := False; exit; + -- Conditional expression + + elsif Nkind (P) = N_Conditional_Expression then + declare + Cond : constant Node_Id := First (Expressions (P)); + Texp : constant Node_Id := Next (Cond); + Fexp : constant Node_Id := Next (Texp); + + begin + if Compile_Time_Known_Value (Cond) then + + -- Condition is True and we are in the right operand + + if Is_True (Expr_Value (Cond)) + and then OldP = Fexp + then + Msgs := False; + exit; + + -- Condition is False and we are in the left operand + + elsif Is_False (Expr_Value (Cond)) + and then OldP = Texp + then + Msgs := False; + exit; + end if; + end if; + end; + + -- Special case for component association in aggregates, where + -- we want to keep climbing up to the parent aggregate. + elsif Nkind (P) = N_Component_Association and then Nkind (Parent (P)) = N_Aggregate then - null; -- Keep going. + null; + + -- Keep going if within subexpression else exit when Nkind (P) not in N_Subexpr; @@ -1148,17 +1783,18 @@ package body Sem_Util is if Wmsg then if Inside_Init_Proc then Error_Msg_NEL - ("\& will be raised for objects of this type!?", + ("\?& will be raised for objects of this type", N, Standard_Constraint_Error, Eloc); else Error_Msg_NEL - ("\& will be raised at run time!?", + ("\?& will be raised at run time", N, Standard_Constraint_Error, Eloc); end if; + else - Error_Msg_NEL - ("\static expression raises&!", - N, Standard_Constraint_Error, Eloc); + Error_Msg + ("\static expression fails Constraint_Check", Eloc); + Set_Error_Posted (N); end if; end if; end if; @@ -1177,6 +1813,42 @@ package body Sem_Util is end if; end Conditional_Delay; + ------------------------- + -- Copy_Parameter_List -- + ------------------------- + + function Copy_Parameter_List (Subp_Id : Entity_Id) return List_Id is + Loc : constant Source_Ptr := Sloc (Subp_Id); + Plist : List_Id; + Formal : Entity_Id; + + begin + if No (First_Formal (Subp_Id)) then + return No_List; + else + Plist := New_List; + Formal := First_Formal (Subp_Id); + while Present (Formal) loop + Append + (Make_Parameter_Specification (Loc, + Defining_Identifier => + Make_Defining_Identifier (Sloc (Formal), + Chars => Chars (Formal)), + In_Present => In_Present (Parent (Formal)), + Out_Present => Out_Present (Parent (Formal)), + Parameter_Type => + New_Reference_To (Etype (Formal), Loc), + Expression => + New_Copy_Tree (Expression (Parent (Formal)))), + Plist); + + Next_Formal (Formal); + end loop; + end if; + + return Plist; + end Copy_Parameter_List; + -------------------- -- Current_Entity -- -------------------- @@ -1203,7 +1875,6 @@ package body Sem_Util is begin E := Get_Name_Entity_Id (Chars (N)); - while Present (E) and then Scope (E) /= CS and then (not Transient_Case or else Scope (E) /= Scope (CS)) @@ -1242,7 +1913,6 @@ package body Sem_Util is function Current_Subprogram return Entity_Id is Scop : constant Entity_Id := Current_Scope; - begin if Is_Subprogram (Scop) or else Is_Generic_Subprogram (Scop) then return Scop; @@ -1363,8 +2033,8 @@ package body Sem_Util is -------------------------- function Denotes_Discriminant - (N : Node_Id; - Check_Protected : Boolean := False) return Boolean + (N : Node_Id; + Check_Concurrent : Boolean := False) return Boolean is E : Entity_Id; begin @@ -1383,16 +2053,25 @@ package body Sem_Util is return Ekind (E) = E_Discriminant or else - (Check_Protected + (Check_Concurrent and then Ekind (E) = E_In_Parameter and then Present (Discriminal_Link (E)) and then - (Is_Protected_Type (Scope (Discriminal_Link (E))) + (Is_Concurrent_Type (Scope (Discriminal_Link (E))) or else Is_Concurrent_Record_Type (Scope (Discriminal_Link (E))))); end Denotes_Discriminant; + ---------------------- + -- Denotes_Variable -- + ---------------------- + + function Denotes_Variable (N : Node_Id) return Boolean is + begin + return Is_Variable (N) and then Paren_Count (N) = 0; + end Denotes_Variable; + ----------------------------- -- Depends_On_Discriminant -- ----------------------------- @@ -1489,15 +2168,14 @@ package body Sem_Util is ---------------------------- function Enclosing_Generic_Body - (E : Entity_Id) return Node_Id + (N : Node_Id) return Node_Id is P : Node_Id; Decl : Node_Id; Spec : Node_Id; begin - P := Parent (E); - + P := Parent (N); while Present (P) loop if Nkind (P) = N_Package_Body or else Nkind (P) = N_Subprogram_Body @@ -1521,17 +2199,59 @@ package body Sem_Util is return Empty; end Enclosing_Generic_Body; + ---------------------------- + -- Enclosing_Generic_Unit -- + ---------------------------- + + function Enclosing_Generic_Unit + (N : Node_Id) return Node_Id + is + P : Node_Id; + Decl : Node_Id; + Spec : Node_Id; + + begin + P := Parent (N); + while Present (P) loop + if Nkind (P) = N_Generic_Package_Declaration + or else Nkind (P) = N_Generic_Subprogram_Declaration + then + return P; + + elsif Nkind (P) = N_Package_Body + or else Nkind (P) = N_Subprogram_Body + then + Spec := Corresponding_Spec (P); + + if Present (Spec) then + Decl := Unit_Declaration_Node (Spec); + + if Nkind (Decl) = N_Generic_Package_Declaration + or else Nkind (Decl) = N_Generic_Subprogram_Declaration + then + return Decl; + end if; + end if; + end if; + + P := Parent (P); + end loop; + + return Empty; + end Enclosing_Generic_Unit; + ------------------------------- -- Enclosing_Lib_Unit_Entity -- ------------------------------- function Enclosing_Lib_Unit_Entity return Entity_Id is - Unit_Entity : Entity_Id := Current_Scope; + Unit_Entity : Entity_Id; begin -- Look for enclosing library unit entity by following scope links. -- Equivalent to, but faster than indexing through the scope stack. + Unit_Entity := Current_Scope; while (Present (Scope (Unit_Entity)) and then Scope (Unit_Entity) /= Standard_Standard) and not Is_Child_Unit (Unit_Entity) @@ -1547,9 +2267,10 @@ package body Sem_Util is ----------------------------- function Enclosing_Lib_Unit_Node (N : Node_Id) return Node_Id is - Current_Node : Node_Id := N; + Current_Node : Node_Id; begin + Current_Node := N; while Present (Current_Node) and then Nkind (Current_Node) /= N_Compilation_Unit loop @@ -1574,10 +2295,15 @@ package body Sem_Util is if Dynamic_Scope = Standard_Standard then return Empty; + elsif Dynamic_Scope = Empty then + return Empty; + elsif Ekind (Dynamic_Scope) = E_Subprogram_Body then return Corresponding_Spec (Parent (Parent (Dynamic_Scope))); - elsif Ekind (Dynamic_Scope) = E_Block then + elsif Ekind (Dynamic_Scope) = E_Block + or else Ekind (Dynamic_Scope) = E_Return_Statement + then return Enclosing_Subprogram (Dynamic_Scope); elsif Ekind (Dynamic_Scope) = E_Task_Type then @@ -1613,7 +2339,7 @@ package body Sem_Util is -- Enter_Name -- ---------------- - procedure Enter_Name (Def_Id : Node_Id) is + procedure Enter_Name (Def_Id : Entity_Id) is C : constant Entity_Id := Current_Entity (Def_Id); E : constant Entity_Id := Current_Entity_In_Scope (Def_Id); S : constant Entity_Id := Current_Scope; @@ -1685,7 +2411,6 @@ package body Sem_Util is -- entity in the scope. Prev := First_Entity (Current_Scope); - while Present (Prev) and then Next_Entity (Prev) /= E loop @@ -1742,13 +2467,38 @@ package body Sem_Util is then return; + -- If the homograph is a protected component renaming, it should not + -- be hiding the current entity. Such renamings are treated as weak + -- declarations. + + elsif Is_Prival (E) then + Set_Is_Immediately_Visible (E, False); + + -- In this case the current entity is a protected component renaming. + -- Perform minimal decoration by setting the scope and return since + -- the prival should not be hiding other visible entities. + + elsif Is_Prival (Def_Id) then + Set_Scope (Def_Id, Current_Scope); + return; + + -- Analogous to privals, the discriminal generated for an entry + -- index parameter acts as a weak declaration. Perform minimal + -- decoration to avoid bogus errors. + + elsif Is_Discriminal (Def_Id) + and then Ekind (Discriminal_Link (Def_Id)) = E_Entry_Index_Parameter + then + Set_Scope (Def_Id, Current_Scope); + return; + -- In the body or private part of an instance, a type extension -- may introduce a component with the same name as that of an -- actual. The legality rule is not enforced, but the semantics -- of the full type with two components of the same name are not -- clear at this point ??? - elsif In_Instance_Not_Visible then + elsif In_Instance_Not_Visible then null; -- When compiling a package body, some child units may have become @@ -1783,21 +2533,19 @@ package body Sem_Util is and then Nkind (Parent (Def_Id)) = N_Private_Type_Declaration then Error_Msg_N - ("incomplete type cannot be completed" & - " with a private declaration", - Parent (Def_Id)); + ("incomplete type cannot be completed with a private " & + "declaration", Parent (Def_Id)); Set_Is_Immediately_Visible (E, False); Set_Full_View (E, Def_Id); + -- An inherited component of a record conflicts with a new + -- discriminant. The discriminant is inserted first in the scope, + -- but the error should be posted on it, not on the component. + elsif Ekind (E) = E_Discriminant and then Present (Scope (Def_Id)) and then Scope (Def_Id) /= Current_Scope then - -- An inherited component of a record conflicts with - -- a new discriminant. The discriminant is inserted first - -- in the scope, but the error should be posted on it, not - -- on the component. - Error_Msg_Sloc := Sloc (Def_Id); Error_Msg_N ("& conflicts with declaration#", E); return; @@ -1827,8 +2575,8 @@ package body Sem_Util is end if; end if; - if Nkind (Parent (Parent (Def_Id))) - = N_Generic_Subprogram_Declaration + if Nkind (Parent (Parent (Def_Id))) = + N_Generic_Subprogram_Declaration and then Def_Id = Defining_Entity (Specification (Parent (Parent (Def_Id)))) then @@ -1894,12 +2642,40 @@ package body Sem_Util is -- Warn if new entity hides an old one - if Warn_On_Hiding - and then Present (C) - and then Length_Of_Name (Chars (C)) /= 1 - and then Comes_From_Source (C) - and then Comes_From_Source (Def_Id) - and then In_Extended_Main_Source_Unit (Def_Id) + if Warn_On_Hiding and then Present (C) + + -- Don't warn for record components since they always have a well + -- defined scope which does not confuse other uses. Note that in + -- some cases, Ekind has not been set yet. + + and then Ekind (C) /= E_Component + and then Ekind (C) /= E_Discriminant + and then Nkind (Parent (C)) /= N_Component_Declaration + and then Ekind (Def_Id) /= E_Component + and then Ekind (Def_Id) /= E_Discriminant + and then Nkind (Parent (Def_Id)) /= N_Component_Declaration + + -- Don't warn for one character variables. It is too common to use + -- such variables as locals and will just cause too many false hits. + + and then Length_Of_Name (Chars (C)) /= 1 + + -- Don't warn for non-source entities + + and then Comes_From_Source (C) + and then Comes_From_Source (Def_Id) + + -- Don't warn unless entity in question is in extended main source + + and then In_Extended_Main_Source_Unit (Def_Id) + + -- Finally, the hidden entity must be either immediately visible + -- or use visible (from a used package) + + and then + (Is_Immediately_Visible (C) + or else + Is_Potentially_Use_Visible (C)) then Error_Msg_Sloc := Sloc (C); Error_Msg_N ("declaration hides &#?", Def_Id); @@ -1919,7 +2695,7 @@ package body Sem_Util is if Is_Array_Type (T) then Error_Msg_Node_2 := T; Error_Msg_NE - ("component type& of type& is limited", N, Component_Type (T)); + ("\component type& of type& is limited", N, Component_Type (T)); Explain_Limited_Type (Component_Type (T), N); elsif Is_Record_Type (T) then @@ -1959,6 +2735,70 @@ package body Sem_Util is end if; end Explain_Limited_Type; + ----------------- + -- Find_Actual -- + ----------------- + + procedure Find_Actual + (N : Node_Id; + Formal : out Entity_Id; + Call : out Node_Id) + is + Parnt : constant Node_Id := Parent (N); + Actual : Node_Id; + + begin + if (Nkind (Parnt) = N_Indexed_Component + or else + Nkind (Parnt) = N_Selected_Component) + and then N = Prefix (Parnt) + then + Find_Actual (Parnt, Formal, Call); + return; + + elsif Nkind (Parnt) = N_Parameter_Association + and then N = Explicit_Actual_Parameter (Parnt) + then + Call := Parent (Parnt); + + elsif Nkind (Parnt) = N_Procedure_Call_Statement then + Call := Parnt; + + else + Formal := Empty; + Call := Empty; + return; + end if; + + -- If we have a call to a subprogram look for the parameter. Note that + -- we exclude overloaded calls, since we don't know enough to be sure + -- of giving the right answer in this case. + + if Is_Entity_Name (Name (Call)) + and then Present (Entity (Name (Call))) + and then Is_Overloadable (Entity (Name (Call))) + and then not Is_Overloaded (Name (Call)) + then + -- Fall here if we are definitely a parameter + + Actual := First_Actual (Call); + Formal := First_Formal (Entity (Name (Call))); + while Present (Formal) and then Present (Actual) loop + if Actual = N then + return; + else + Actual := Next_Actual (Actual); + Formal := Next_Formal (Formal); + end if; + end loop; + end if; + + -- Fall through here if we did not find matching actual + + Formal := Empty; + Call := Empty; + end Find_Actual; + ------------------------------------- -- Find_Corresponding_Discriminant -- ------------------------------------- @@ -2006,6 +2846,85 @@ package body Sem_Util is raise Program_Error; end Find_Corresponding_Discriminant; + -------------------------- + -- Find_Overlaid_Object -- + -------------------------- + + function Find_Overlaid_Object (N : Node_Id) return Entity_Id is + Expr : Node_Id; + + begin + -- We are looking for one of the two following forms: + + -- for X'Address use Y'Address + + -- or + + -- Const : constant Address := expr; + -- ... + -- for X'Address use Const; + + -- In the second case, the expr is either Y'Address, or recursively a + -- constant that eventually references Y'Address. + + if Nkind (N) = N_Attribute_Definition_Clause + and then Chars (N) = Name_Address + then + -- This loop checks the form of the expression for Y'Address where Y + -- is an object entity name. The first loop checks the original + -- expression in the attribute definition clause. Subsequent loops + -- check referenced constants. + + Expr := Expression (N); + loop + -- Check for Y'Address where Y is an object entity + + if Nkind (Expr) = N_Attribute_Reference + and then Attribute_Name (Expr) = Name_Address + and then Is_Entity_Name (Prefix (Expr)) + and then Is_Object (Entity (Prefix (Expr))) + then + return Entity (Prefix (Expr)); + + -- Check for Const where Const is a constant entity + + elsif Is_Entity_Name (Expr) + and then Ekind (Entity (Expr)) = E_Constant + then + Expr := Constant_Value (Entity (Expr)); + + -- Anything else does not need checking + + else + exit; + end if; + end loop; + end if; + + return Empty; + end Find_Overlaid_Object; + + ------------------------- + -- Find_Parameter_Type -- + ------------------------- + + function Find_Parameter_Type (Param : Node_Id) return Entity_Id is + begin + if Nkind (Param) /= N_Parameter_Specification then + return Empty; + + -- For an access parameter, obtain the type from the formal entity + -- itself, because access to subprogram nodes do not carry a type. + -- Shouldn't we always use the formal entity ??? + + elsif Nkind (Parameter_Type (Param)) = N_Access_Definition then + return Etype (Defining_Identifier (Param)); + + else + return Etype (Parameter_Type (Param)); + end if; + end Find_Parameter_Type; + ----------------------------- -- Find_Static_Alternative -- ----------------------------- @@ -2022,7 +2941,6 @@ package body Sem_Util is Search : loop if Nkind (Alt) /= N_Pragma then Choice := First (Discrete_Choices (Alt)); - while Present (Choice) loop -- Others choice, always matches @@ -2131,8 +3049,7 @@ package body Sem_Util is Ent := Defining_Identifier (Ent); end if; - -- Compute recursively the qualification. Only "Standard" has no - -- scope. + -- Compute qualification recursively (only "Standard" has no scope) if Present (Scope (Scope (Ent))) then Parent_Name := Internal_Full_Qualified_Name (Scope (Ent)); @@ -2157,7 +3074,7 @@ package body Sem_Util is -- Generates the entity name in upper case - Get_Name_String (Chars (Ent)); + Get_Decoded_Name_String (Chars (Ent)); Set_All_Upper_Case; Store_String_Chars (Name_Buffer (1 .. Name_Len)); return End_String; @@ -2167,7 +3084,7 @@ package body Sem_Util is begin Res := Internal_Full_Qualified_Name (E); - Store_String_Char (Get_Char_Code (ASCII.nul)); + Store_String_Char (Get_Char_Code (ASCII.NUL)); return End_String; end Full_Qualified_Name; @@ -2206,16 +3123,21 @@ package body Sem_Util is while Present (Comp_Item) loop - -- Skip the tag of a tagged record, as well as all items - -- that are not user components (anonymous types, rep clauses, - -- Parent field, controller field). + -- Skip the tag of a tagged record, the interface tags, as well + -- as all items that are not user components (anonymous types, + -- rep clauses, Parent field, controller field). - if Nkind (Comp_Item) = N_Component_Declaration - and then Chars (Defining_Identifier (Comp_Item)) /= Name_uTag - and then Chars (Defining_Identifier (Comp_Item)) /= Name_uParent - and then Chars (Defining_Identifier (Comp_Item)) /= Name_uController - then - Append_Elmt (Defining_Identifier (Comp_Item), Into); + if Nkind (Comp_Item) = N_Component_Declaration then + declare + Comp : constant Entity_Id := Defining_Identifier (Comp_Item); + begin + if not Is_Tag (Comp) + and then Chars (Comp) /= Name_uParent + and then Chars (Comp) /= Name_uController + then + Append_Elmt (Comp, Into); + end if; + end; end if; Next (Comp_Item); @@ -2247,7 +3169,6 @@ package body Sem_Util is and then Is_Derived_Type (Typ) and then Present (Stored_Constraint (Typ)) then - -- If the type is a tagged type with inherited discriminants, -- use the stored constraint on the parent in order to find -- the values of discriminants that are otherwise hidden by an @@ -2267,16 +3188,13 @@ package body Sem_Util is begin D := First_Discriminant (Etype (Typ)); C := First_Elmt (Stored_Constraint (Typ)); - - while Present (D) - and then Present (C) - loop + while Present (D) and then Present (C) loop if Chars (Discrim_Name) = Chars (D) then if Is_Entity_Name (Node (C)) and then Entity (Node (C)) = Entity (Discrim) then - -- D is renamed by Discrim, whose value is - -- given in Assoc. + -- D is renamed by Discrim, whose value is given in + -- Assoc. null; @@ -2290,7 +3208,7 @@ package body Sem_Util is exit Find_Constraint; end if; - D := Next_Discriminant (D); + Next_Discriminant (D); Next_Elmt (C); end loop; end; @@ -2376,7 +3294,7 @@ package body Sem_Util is Atyp : Entity_Id; begin - if not Present (Utyp) then + if No (Utyp) then Utyp := Typ; end if; @@ -2414,9 +3332,9 @@ package body Sem_Util is and then not Has_Unknown_Discriminants (Utyp) and then not (Ekind (Utyp) = E_String_Literal_Subtype) then - -- Nothing to do if in default expression + -- Nothing to do if in spec expression (why not???) - if In_Default_Expression then + if In_Spec_Expression then return Typ; elsif Is_Private_Type (Typ) @@ -2534,10 +3452,7 @@ package body Sem_Util is -- literals to search. Instead, an N_Character_Literal node is created -- with the appropriate Char_Code and Chars fields. - if Root_Type (T) = Standard_Character - or else Root_Type (T) = Standard_Wide_Character - or else Root_Type (T) = Standard_Wide_Wide_Character - then + if Is_Standard_Character_Type (T) then Set_Character_Literal_Name (UI_To_CC (Pos)); return Make_Character_Literal (Loc, @@ -2645,14 +3560,24 @@ package body Sem_Util is return Entity_Id (Get_Name_Table_Info (Id)); end Get_Name_Entity_Id; + ------------------- + -- Get_Pragma_Id -- + ------------------- + + function Get_Pragma_Id (N : Node_Id) return Pragma_Id is + begin + return Get_Pragma_Id (Pragma_Name (N)); + end Get_Pragma_Id; + --------------------------- -- Get_Referenced_Object -- --------------------------- function Get_Referenced_Object (N : Node_Id) return Node_Id is - R : Node_Id := N; + R : Node_Id; begin + R := N; while Is_Entity_Name (R) and then Present (Renamed_Object (Entity (R))) loop @@ -2662,6 +3587,22 @@ package body Sem_Util is return R; end Get_Referenced_Object; + ------------------------ + -- Get_Renamed_Entity -- + ------------------------ + + function Get_Renamed_Entity (E : Entity_Id) return Entity_Id is + R : Entity_Id; + + begin + R := E; + while Present (Renamed_Entity (R)) loop + R := Renamed_Entity (R); + end loop; + + return R; + end Get_Renamed_Entity; + ------------------------- -- Get_Subprogram_Body -- ------------------------- @@ -2691,6 +3632,57 @@ package body Sem_Util is end if; end Get_Subprogram_Body; + --------------------------- + -- Get_Subprogram_Entity -- + --------------------------- + + function Get_Subprogram_Entity (Nod : Node_Id) return Entity_Id is + Nam : Node_Id; + Proc : Entity_Id; + + begin + if Nkind (Nod) = N_Accept_Statement then + Nam := Entry_Direct_Name (Nod); + + -- For an entry call, the prefix of the call is a selected component. + -- Need additional code for internal calls ??? + + elsif Nkind (Nod) = N_Entry_Call_Statement then + if Nkind (Name (Nod)) = N_Selected_Component then + Nam := Entity (Selector_Name (Name (Nod))); + else + Nam := Empty; + end if; + + else + Nam := Name (Nod); + end if; + + if Nkind (Nam) = N_Explicit_Dereference then + Proc := Etype (Prefix (Nam)); + elsif Is_Entity_Name (Nam) then + Proc := Entity (Nam); + else + return Empty; + end if; + + if Is_Object (Proc) then + Proc := Etype (Proc); + end if; + + if Ekind (Proc) = E_Access_Subprogram_Type then + Proc := Directly_Designated_Type (Proc); + end if; + + if not Is_Subprogram (Proc) + and then Ekind (Proc) /= E_Subprogram_Type + then + return Empty; + else + return Proc; + end if; + end Get_Subprogram_Entity; + ----------------------------- -- Get_Task_Body_Procedure -- ----------------------------- @@ -2698,11 +3690,14 @@ package body Sem_Util is function Get_Task_Body_Procedure (E : Entity_Id) return Node_Id is begin -- Note: A task type may be the completion of a private type with - -- discriminants. when performing elaboration checks on a task + -- discriminants. When performing elaboration checks on a task -- declaration, the current view of the type may be the private one, -- and the procedure that holds the body of the task is held in its -- underlying type. + -- This is an odd function, why not have Task_Body_Procedure do + -- the following digging??? + return Task_Body_Procedure (Underlying_Type (Root_Type (E))); end Get_Task_Body_Procedure; @@ -2734,17 +3729,21 @@ package body Sem_Util is Comp : Entity_Id; begin - Comp := First_Entity (Typ); + -- Loop to Check components + + Comp := First_Component_Or_Discriminant (Typ); while Present (Comp) loop - if (Ekind (Comp) = E_Component - or else - Ekind (Comp) = E_Discriminant) - and then Has_Access_Values (Etype (Comp)) + + -- Check for access component, tag field does not count, even + -- though it is implemented internally using an access type. + + if Has_Access_Values (Etype (Comp)) + and then Chars (Comp) /= Name_uTag then return True; end if; - Next_Entity (Comp); + Next_Component_Or_Discriminant (Comp); end loop; end; @@ -2755,6 +3754,330 @@ package body Sem_Util is end if; end Has_Access_Values; + ------------------------------ + -- Has_Compatible_Alignment -- + ------------------------------ + + function Has_Compatible_Alignment + (Obj : Entity_Id; + Expr : Node_Id) return Alignment_Result + is + function Has_Compatible_Alignment_Internal + (Obj : Entity_Id; + Expr : Node_Id; + Default : Alignment_Result) return Alignment_Result; + -- This is the internal recursive function that actually does the work. + -- There is one additional parameter, which says what the result should + -- be if no alignment information is found, and there is no definite + -- indication of compatible alignments. At the outer level, this is set + -- to Unknown, but for internal recursive calls in the case where types + -- are known to be correct, it is set to Known_Compatible. + + --------------------------------------- + -- Has_Compatible_Alignment_Internal -- + --------------------------------------- + + function Has_Compatible_Alignment_Internal + (Obj : Entity_Id; + Expr : Node_Id; + Default : Alignment_Result) return Alignment_Result + is + Result : Alignment_Result := Known_Compatible; + -- Set to result if Problem_Prefix or Problem_Offset returns True. + -- Note that once a value of Known_Incompatible is set, it is sticky + -- and does not get changed to Unknown (the value in Result only gets + -- worse as we go along, never better). + + procedure Check_Offset (Offs : Uint); + -- Called when Expr is a selected or indexed component with Offs set + -- to resp Component_First_Bit or Component_Size. Checks that if the + -- offset is specified it is compatible with the object alignment + -- requirements. The value in Result is modified accordingly. + + procedure Check_Prefix; + -- Checks the prefix recursively in the case where the expression + -- is an indexed or selected component. + + procedure Set_Result (R : Alignment_Result); + -- If R represents a worse outcome (unknown instead of known + -- compatible, or known incompatible), then set Result to R. + + ------------------ + -- Check_Offset -- + ------------------ + + procedure Check_Offset (Offs : Uint) is + begin + -- Unspecified or zero offset is always OK + + if Offs = No_Uint or else Offs = Uint_0 then + null; + + -- If we do not know required alignment, any non-zero offset is + -- a potential problem (but certainly may be OK, so result is + -- unknown). + + elsif Unknown_Alignment (Obj) then + Set_Result (Unknown); + + -- If we know the required alignment, see if offset is compatible + + else + if Offs mod (System_Storage_Unit * Alignment (Obj)) /= 0 then + Set_Result (Known_Incompatible); + end if; + end if; + end Check_Offset; + + ------------------ + -- Check_Prefix -- + ------------------ + + procedure Check_Prefix is + begin + -- The subtlety here is that in doing a recursive call to check + -- the prefix, we have to decide what to do in the case where we + -- don't find any specific indication of an alignment problem. + + -- At the outer level, we normally set Unknown as the result in + -- this case, since we can only set Known_Compatible if we really + -- know that the alignment value is OK, but for the recursive + -- call, in the case where the types match, and we have not + -- specified a peculiar alignment for the object, we are only + -- concerned about suspicious rep clauses, the default case does + -- not affect us, since the compiler will, in the absence of such + -- rep clauses, ensure that the alignment is correct. + + if Default = Known_Compatible + or else + (Etype (Obj) = Etype (Expr) + and then (Unknown_Alignment (Obj) + or else + Alignment (Obj) = Alignment (Etype (Obj)))) + then + Set_Result + (Has_Compatible_Alignment_Internal + (Obj, Prefix (Expr), Known_Compatible)); + + -- In all other cases, we need a full check on the prefix + + else + Set_Result + (Has_Compatible_Alignment_Internal + (Obj, Prefix (Expr), Unknown)); + end if; + end Check_Prefix; + + ---------------- + -- Set_Result -- + ---------------- + + procedure Set_Result (R : Alignment_Result) is + begin + if R > Result then + Result := R; + end if; + end Set_Result; + + -- Start of processing for Has_Compatible_Alignment_Internal + + begin + -- If Expr is a selected component, we must make sure there is no + -- potentially troublesome component clause, and that the record is + -- not packed. + + if Nkind (Expr) = N_Selected_Component then + + -- Packed record always generate unknown alignment + + if Is_Packed (Etype (Prefix (Expr))) then + Set_Result (Unknown); + end if; + + -- Check possible bad component offset and check prefix + + Check_Offset + (Component_Bit_Offset (Entity (Selector_Name (Expr)))); + Check_Prefix; + + -- If Expr is an indexed component, we must make sure there is no + -- potentially troublesome Component_Size clause and that the array + -- is not bit-packed. + + elsif Nkind (Expr) = N_Indexed_Component then + + -- Bit packed array always generates unknown alignment + + if Is_Bit_Packed_Array (Etype (Prefix (Expr))) then + Set_Result (Unknown); + end if; + + -- Check possible bad component size and check prefix + + Check_Offset (Component_Size (Etype (Prefix (Expr)))); + Check_Prefix; + end if; + + -- Case where we know the alignment of the object + + if Known_Alignment (Obj) then + declare + ObjA : constant Uint := Alignment (Obj); + ExpA : Uint := No_Uint; + SizA : Uint := No_Uint; + + begin + -- If alignment of Obj is 1, then we are always OK + + if ObjA = 1 then + Set_Result (Known_Compatible); + + -- Alignment of Obj is greater than 1, so we need to check + + else + -- See if Expr is an object with known alignment + + if Is_Entity_Name (Expr) + and then Known_Alignment (Entity (Expr)) + then + ExpA := Alignment (Entity (Expr)); + + -- Otherwise, we can use the alignment of the type of + -- Expr given that we already checked for + -- discombobulating rep clauses for the cases of indexed + -- and selected components above. + + elsif Known_Alignment (Etype (Expr)) then + ExpA := Alignment (Etype (Expr)); + end if; + + -- If we got an alignment, see if it is acceptable + + if ExpA /= No_Uint then + if ExpA < ObjA then + Set_Result (Known_Incompatible); + end if; + + -- Case of Expr alignment unknown + + else + Set_Result (Default); + end if; + + -- See if size is given. If so, check that it is not too + -- small for the required alignment. + -- See if Expr is an object with known alignment + + if Is_Entity_Name (Expr) + and then Known_Static_Esize (Entity (Expr)) + then + SizA := Esize (Entity (Expr)); + + -- Otherwise, we check the object size of the Expr type + + elsif Known_Static_Esize (Etype (Expr)) then + SizA := Esize (Etype (Expr)); + end if; + + -- If we got a size, see if it is a multiple of the Obj + -- alignment, if not, then the alignment cannot be + -- acceptable, since the size is always a multiple of the + -- alignment. + + if SizA /= No_Uint then + if SizA mod (ObjA * Ttypes.System_Storage_Unit) /= 0 then + Set_Result (Known_Incompatible); + end if; + end if; + end if; + end; + + -- If we can't find the result by direct comparison of alignment + -- values, then there is still one case that we can determine known + -- result, and that is when we can determine that the types are the + -- same, and no alignments are specified. Then we known that the + -- alignments are compatible, even if we don't know the alignment + -- value in the front end. + + elsif Etype (Obj) = Etype (Expr) then + + -- Types are the same, but we have to check for possible size + -- and alignments on the Expr object that may make the alignment + -- different, even though the types are the same. + + if Is_Entity_Name (Expr) then + + -- First check alignment of the Expr object. Any alignment less + -- than Maximum_Alignment is worrisome since this is the case + -- where we do not know the alignment of Obj. + + if Known_Alignment (Entity (Expr)) + and then + UI_To_Int (Alignment (Entity (Expr))) + < Ttypes.Maximum_Alignment + then + Set_Result (Unknown); + + -- Now check size of Expr object. Any size that is not an + -- even multiple of Maximum_Alignment is also worrisome + -- since it may cause the alignment of the object to be less + -- than the alignment of the type. + + elsif Known_Static_Esize (Entity (Expr)) + and then + (UI_To_Int (Esize (Entity (Expr))) mod + (Ttypes.Maximum_Alignment * Ttypes.System_Storage_Unit)) + /= 0 + then + Set_Result (Unknown); + + -- Otherwise same type is decisive + + else + Set_Result (Known_Compatible); + end if; + end if; + + -- Another case to deal with is when there is an explicit size or + -- alignment clause when the types are not the same. If so, then the + -- result is Unknown. We don't need to do this test if the Default is + -- Unknown, since that result will be set in any case. + + elsif Default /= Unknown + and then (Has_Size_Clause (Etype (Expr)) + or else + Has_Alignment_Clause (Etype (Expr))) + then + Set_Result (Unknown); + + -- If no indication found, set default + + else + Set_Result (Default); + end if; + + -- Return worst result found + + return Result; + end Has_Compatible_Alignment_Internal; + + -- Start of processing for Has_Compatible_Alignment + + begin + -- If Obj has no specified alignment, then set alignment from the type + -- alignment. Perhaps we should always do this, but for sure we should + -- do it when there is an address clause since we can do more if the + -- alignment is known. + + if Unknown_Alignment (Obj) then + Set_Alignment (Obj, Alignment (Etype (Obj))); + end if; + + -- Now do the internal call that does all the work + + return Has_Compatible_Alignment_Internal (Obj, Expr, Unknown); + end Has_Compatible_Alignment; + ---------------------- -- Has_Declarations -- ---------------------- @@ -2832,172 +4155,216 @@ package body Sem_Util is and then Includes_Infinities (Scalar_Range (E)); end Has_Infinities; - ------------------------ - -- Has_Null_Extension -- - ------------------------ + -------------------- + -- Has_Interfaces -- + -------------------- - function Has_Null_Extension (T : Entity_Id) return Boolean is - B : constant Entity_Id := Base_Type (T); - Comps : Node_Id; - Ext : Node_Id; + function Has_Interfaces + (T : Entity_Id; + Use_Full_View : Boolean := True) return Boolean + is + Typ : Entity_Id; begin - if Nkind (Parent (B)) = N_Full_Type_Declaration - and then Present (Record_Extension_Part (Type_Definition (Parent (B)))) - then - Ext := Record_Extension_Part (Type_Definition (Parent (B))); - - if Present (Ext) then - if Null_Present (Ext) then - return True; - else - Comps := Component_List (Ext); - - -- The null component list is rewritten during analysis to - -- include the parent component. Any other component indicates - -- that the extension was not originally null. - - return Null_Present (Comps) - or else No (Next (First (Component_Items (Comps)))); - end if; - else - return False; - end if; + -- Handle concurrent types + if Is_Concurrent_Type (T) then + Typ := Corresponding_Record_Type (T); else - return False; + Typ := T; end if; - end Has_Null_Extension; - --------------------------- - -- Has_Private_Component -- - --------------------------- + if not Present (Typ) + or else not Is_Record_Type (Typ) + or else not Is_Tagged_Type (Typ) + then + return False; + end if; - function Has_Private_Component (Type_Id : Entity_Id) return Boolean is - Btype : Entity_Id := Base_Type (Type_Id); - Component : Entity_Id; + -- Handle private types - begin - if Error_Posted (Type_Id) - or else Error_Posted (Btype) + if Use_Full_View + and then Present (Full_View (Typ)) then - return False; + Typ := Full_View (Typ); end if; - if Is_Class_Wide_Type (Btype) then - Btype := Root_Type (Btype); + -- Handle concurrent record types + + if Is_Concurrent_Record_Type (Typ) + and then Is_Non_Empty_List (Abstract_Interface_List (Typ)) + then + return True; end if; - if Is_Private_Type (Btype) then - declare - UT : constant Entity_Id := Underlying_Type (Btype); - begin - if No (UT) then + loop + if Is_Interface (Typ) + or else + (Is_Record_Type (Typ) + and then Present (Interfaces (Typ)) + and then not Is_Empty_Elmt_List (Interfaces (Typ))) + then + return True; + end if; - if No (Full_View (Btype)) then - return not Is_Generic_Type (Btype) - and then not Is_Generic_Type (Root_Type (Btype)); + exit when Etype (Typ) = Typ - else - return not Is_Generic_Type (Root_Type (Full_View (Btype))); - end if; + -- Handle private types - else - return not Is_Frozen (UT) and then Has_Private_Component (UT); - end if; - end; - elsif Is_Array_Type (Btype) then - return Has_Private_Component (Component_Type (Btype)); + or else (Present (Full_View (Etype (Typ))) + and then Full_View (Etype (Typ)) = Typ) - elsif Is_Record_Type (Btype) then + -- Protect the frontend against wrong source with cyclic + -- derivations - Component := First_Component (Btype); - while Present (Component) loop + or else Etype (Typ) = T; - if Has_Private_Component (Etype (Component)) then - return True; - end if; + -- Climb to the ancestor type handling private types - Next_Component (Component); - end loop; + if Present (Full_View (Etype (Typ))) then + Typ := Full_View (Etype (Typ)); + else + Typ := Etype (Typ); + end if; + end loop; - return False; + return False; + end Has_Interfaces; - elsif Is_Protected_Type (Btype) - and then Present (Corresponding_Record_Type (Btype)) - then - return Has_Private_Component (Corresponding_Record_Type (Btype)); + ------------------------ + -- Has_Null_Exclusion -- + ------------------------ - else - return False; - end if; - end Has_Private_Component; + function Has_Null_Exclusion (N : Node_Id) return Boolean is + begin + case Nkind (N) is + when N_Access_Definition | + N_Access_Function_Definition | + N_Access_Procedure_Definition | + N_Access_To_Object_Definition | + N_Allocator | + N_Derived_Type_Definition | + N_Function_Specification | + N_Subtype_Declaration => + return Null_Exclusion_Present (N); + + when N_Component_Definition | + N_Formal_Object_Declaration | + N_Object_Renaming_Declaration => + if Present (Subtype_Mark (N)) then + return Null_Exclusion_Present (N); + else pragma Assert (Present (Access_Definition (N))); + return Null_Exclusion_Present (Access_Definition (N)); + end if; - ---------------- - -- Has_Stream -- - ---------------- + when N_Discriminant_Specification => + if Nkind (Discriminant_Type (N)) = N_Access_Definition then + return Null_Exclusion_Present (Discriminant_Type (N)); + else + return Null_Exclusion_Present (N); + end if; - function Has_Stream (T : Entity_Id) return Boolean is - E : Entity_Id; + when N_Object_Declaration => + if Nkind (Object_Definition (N)) = N_Access_Definition then + return Null_Exclusion_Present (Object_Definition (N)); + else + return Null_Exclusion_Present (N); + end if; - begin - if No (T) then - return False; + when N_Parameter_Specification => + if Nkind (Parameter_Type (N)) = N_Access_Definition then + return Null_Exclusion_Present (Parameter_Type (N)); + else + return Null_Exclusion_Present (N); + end if; - elsif Is_RTE (Root_Type (T), RE_Root_Stream_Type) then - return True; + when others => + return False; - elsif Is_Array_Type (T) then - return Has_Stream (Component_Type (T)); + end case; + end Has_Null_Exclusion; - elsif Is_Record_Type (T) then - E := First_Component (T); - while Present (E) loop - if Has_Stream (Etype (E)) then + ------------------------ + -- Has_Null_Extension -- + ------------------------ + + function Has_Null_Extension (T : Entity_Id) return Boolean is + B : constant Entity_Id := Base_Type (T); + Comps : Node_Id; + Ext : Node_Id; + + begin + if Nkind (Parent (B)) = N_Full_Type_Declaration + and then Present (Record_Extension_Part (Type_Definition (Parent (B)))) + then + Ext := Record_Extension_Part (Type_Definition (Parent (B))); + + if Present (Ext) then + if Null_Present (Ext) then return True; else - Next_Component (E); - end if; - end loop; + Comps := Component_List (Ext); - return False; + -- The null component list is rewritten during analysis to + -- include the parent component. Any other component indicates + -- that the extension was not originally null. - elsif Is_Private_Type (T) then - return Has_Stream (Underlying_Type (T)); + return Null_Present (Comps) + or else No (Next (First (Component_Items (Comps)))); + end if; + else + return False; + end if; else return False; end if; - end Has_Stream; + end Has_Null_Extension; - -------------------------- - -- Has_Tagged_Component -- - -------------------------- + ------------------------------- + -- Has_Overriding_Initialize -- + ------------------------------- - function Has_Tagged_Component (Typ : Entity_Id) return Boolean is + function Has_Overriding_Initialize (T : Entity_Id) return Boolean is + BT : constant Entity_Id := Base_Type (T); Comp : Entity_Id; + P : Elmt_Id; begin - if Is_Private_Type (Typ) - and then Present (Underlying_Type (Typ)) - then - return Has_Tagged_Component (Underlying_Type (Typ)); + if Is_Controlled (BT) then - elsif Is_Array_Type (Typ) then - return Has_Tagged_Component (Component_Type (Typ)); + -- For derived types, check immediate ancestor, excluding + -- Controlled itself. - elsif Is_Tagged_Type (Typ) then - return True; + if Is_Derived_Type (BT) + and then not In_Predefined_Unit (Etype (BT)) + and then Has_Overriding_Initialize (Etype (BT)) + then + return True; - elsif Is_Record_Type (Typ) then - Comp := First_Component (Typ); + elsif Present (Primitive_Operations (BT)) then + P := First_Elmt (Primitive_Operations (BT)); + while Present (P) loop + if Chars (Node (P)) = Name_Initialize + and then Comes_From_Source (Node (P)) + then + return True; + end if; + Next_Elmt (P); + end loop; + end if; + + return False; + + elsif Has_Controlled_Component (BT) then + Comp := First_Component (BT); while Present (Comp) loop - if Has_Tagged_Component (Etype (Comp)) then + if Has_Overriding_Initialize (Etype (Comp)) then return True; end if; - Comp := Next_Component (Typ); + Next_Component (Comp); end loop; return False; @@ -3005,1972 +4372,3028 @@ package body Sem_Util is else return False; end if; - end Has_Tagged_Component; + end Has_Overriding_Initialize; - ----------------- - -- In_Instance -- - ----------------- + -------------------------------------- + -- Has_Preelaborable_Initialization -- + -------------------------------------- - function In_Instance return Boolean is - S : Entity_Id := Current_Scope; + function Has_Preelaborable_Initialization (E : Entity_Id) return Boolean is + Has_PE : Boolean; - begin - while Present (S) - and then S /= Standard_Standard - loop - if (Ekind (S) = E_Function - or else Ekind (S) = E_Package - or else Ekind (S) = E_Procedure) - and then Is_Generic_Instance (S) - then - return True; - end if; + procedure Check_Components (E : Entity_Id); + -- Check component/discriminant chain, sets Has_PE False if a component + -- or discriminant does not meet the preelaborable initialization rules. - S := Scope (S); - end loop; + ---------------------- + -- Check_Components -- + ---------------------- - return False; - end In_Instance; + procedure Check_Components (E : Entity_Id) is + Ent : Entity_Id; + Exp : Node_Id; - ---------------------- - -- In_Instance_Body -- - ---------------------- + function Is_Preelaborable_Expression (N : Node_Id) return Boolean; + -- Returns True if and only if the expression denoted by N does not + -- violate restrictions on preelaborable constructs (RM-10.2.1(5-9)). - function In_Instance_Body return Boolean is - S : Entity_Id := Current_Scope; + --------------------------------- + -- Is_Preelaborable_Expression -- + --------------------------------- - begin - while Present (S) - and then S /= Standard_Standard - loop - if (Ekind (S) = E_Function - or else Ekind (S) = E_Procedure) - and then Is_Generic_Instance (S) - then - return True; + function Is_Preelaborable_Expression (N : Node_Id) return Boolean is + Exp : Node_Id; + Assn : Node_Id; + Choice : Node_Id; + Comp_Type : Entity_Id; + Is_Array_Aggr : Boolean; - elsif Ekind (S) = E_Package - and then In_Package_Body (S) - and then Is_Generic_Instance (S) - then - return True; - end if; + begin + if Is_Static_Expression (N) then + return True; - S := Scope (S); - end loop; + elsif Nkind (N) = N_Null then + return True; - return False; - end In_Instance_Body; + -- Attributes are allowed in general, even if their prefix is a + -- formal type. (It seems that certain attributes known not to be + -- static might not be allowed, but there are no rules to prevent + -- them.) - ----------------------------- - -- In_Instance_Not_Visible -- - ----------------------------- + elsif Nkind (N) = N_Attribute_Reference then + return True; - function In_Instance_Not_Visible return Boolean is - S : Entity_Id := Current_Scope; + -- The name of a discriminant evaluated within its parent type is + -- defined to be preelaborable (10.2.1(8)). Note that we test for + -- names that denote discriminals as well as discriminants to + -- catch references occurring within init procs. - begin - while Present (S) - and then S /= Standard_Standard - loop - if (Ekind (S) = E_Function - or else Ekind (S) = E_Procedure) - and then Is_Generic_Instance (S) - then - return True; + elsif Is_Entity_Name (N) + and then + (Ekind (Entity (N)) = E_Discriminant + or else + ((Ekind (Entity (N)) = E_Constant + or else Ekind (Entity (N)) = E_In_Parameter) + and then Present (Discriminal_Link (Entity (N))))) + then + return True; - elsif Ekind (S) = E_Package - and then (In_Package_Body (S) or else In_Private_Part (S)) - and then Is_Generic_Instance (S) - then - return True; - end if; + elsif Nkind (N) = N_Qualified_Expression then + return Is_Preelaborable_Expression (Expression (N)); - S := Scope (S); - end loop; + -- For aggregates we have to check that each of the associations + -- is preelaborable. - return False; - end In_Instance_Not_Visible; + elsif Nkind (N) = N_Aggregate + or else Nkind (N) = N_Extension_Aggregate + then + Is_Array_Aggr := Is_Array_Type (Etype (N)); - ------------------------------ - -- In_Instance_Visible_Part -- - ------------------------------ + if Is_Array_Aggr then + Comp_Type := Component_Type (Etype (N)); + end if; - function In_Instance_Visible_Part return Boolean is - S : Entity_Id := Current_Scope; + -- Check the ancestor part of extension aggregates, which must + -- be either the name of a type that has preelaborable init or + -- an expression that is preelaborable. - begin - while Present (S) - and then S /= Standard_Standard - loop - if Ekind (S) = E_Package - and then Is_Generic_Instance (S) - and then not In_Package_Body (S) - and then not In_Private_Part (S) - then - return True; - end if; + if Nkind (N) = N_Extension_Aggregate then + declare + Anc_Part : constant Node_Id := Ancestor_Part (N); - S := Scope (S); - end loop; + begin + if Is_Entity_Name (Anc_Part) + and then Is_Type (Entity (Anc_Part)) + then + if not Has_Preelaborable_Initialization + (Entity (Anc_Part)) + then + return False; + end if; - return False; - end In_Instance_Visible_Part; + elsif not Is_Preelaborable_Expression (Anc_Part) then + return False; + end if; + end; + end if; - ---------------------- - -- In_Packiage_Body -- - ---------------------- + -- Check positional associations - function In_Package_Body return Boolean is - S : Entity_Id := Current_Scope; + Exp := First (Expressions (N)); + while Present (Exp) loop + if not Is_Preelaborable_Expression (Exp) then + return False; + end if; - begin - while Present (S) - and then S /= Standard_Standard - loop - if Ekind (S) = E_Package - and then In_Package_Body (S) - then - return True; - else - S := Scope (S); - end if; - end loop; + Next (Exp); + end loop; - return False; - end In_Package_Body; + -- Check named associations - -------------------------------------- - -- In_Subprogram_Or_Concurrent_Unit -- - -------------------------------------- + Assn := First (Component_Associations (N)); + while Present (Assn) loop + Choice := First (Choices (Assn)); + while Present (Choice) loop + if Is_Array_Aggr then + if Nkind (Choice) = N_Others_Choice then + null; - function In_Subprogram_Or_Concurrent_Unit return Boolean is - E : Entity_Id; - K : Entity_Kind; + elsif Nkind (Choice) = N_Range then + if not Is_Static_Range (Choice) then + return False; + end if; - begin - -- Use scope chain to check successively outer scopes + elsif not Is_Static_Expression (Choice) then + return False; + end if; - E := Current_Scope; - loop - K := Ekind (E); + else + Comp_Type := Etype (Choice); + end if; - if K in Subprogram_Kind - or else K in Concurrent_Kind - or else K in Generic_Subprogram_Kind - then - return True; + Next (Choice); + end loop; - elsif E = Standard_Standard then - return False; - end if; + -- If the association has a <> at this point, then we have + -- to check whether the component's type has preelaborable + -- initialization. Note that this only occurs when the + -- association's corresponding component does not have a + -- default expression, the latter case having already been + -- expanded as an expression for the association. - E := Scope (E); - end loop; - end In_Subprogram_Or_Concurrent_Unit; + if Box_Present (Assn) then + if not Has_Preelaborable_Initialization (Comp_Type) then + return False; + end if; - --------------------- - -- In_Visible_Part -- - --------------------- + -- In the expression case we check whether the expression + -- is preelaborable. - function In_Visible_Part (Scope_Id : Entity_Id) return Boolean is - begin - return - Is_Package (Scope_Id) - and then In_Open_Scopes (Scope_Id) - and then not In_Package_Body (Scope_Id) - and then not In_Private_Part (Scope_Id); - end In_Visible_Part; + elsif + not Is_Preelaborable_Expression (Expression (Assn)) + then + return False; + end if; - --------------------------------- - -- Insert_Explicit_Dereference -- - --------------------------------- + Next (Assn); + end loop; - procedure Insert_Explicit_Dereference (N : Node_Id) is - New_Prefix : constant Node_Id := Relocate_Node (N); - Ent : Entity_Id := Empty; - Pref : Node_Id; - I : Interp_Index; - It : Interp; - T : Entity_Id; + -- If we get here then aggregate as a whole is preelaborable - begin - Save_Interps (N, New_Prefix); - Rewrite (N, - Make_Explicit_Dereference (Sloc (N), Prefix => New_Prefix)); + return True; - Set_Etype (N, Designated_Type (Etype (New_Prefix))); + -- All other cases are not preelaborable - if Is_Overloaded (New_Prefix) then + else + return False; + end if; + end Is_Preelaborable_Expression; - -- The deference is also overloaded, and its interpretations are the - -- designated types of the interpretations of the original node. + -- Start of processing for Check_Components - Set_Etype (N, Any_Type); - Get_First_Interp (New_Prefix, I, It); + begin + -- Loop through entities of record or protected type - while Present (It.Nam) loop - T := It.Typ; + Ent := E; + while Present (Ent) loop - if Is_Access_Type (T) then - Add_One_Interp (N, Designated_Type (T), Designated_Type (T)); - end if; + -- We are interested only in components and discriminants - Get_Next_Interp (I, It); - end loop; + if Ekind (Ent) = E_Component + or else + Ekind (Ent) = E_Discriminant + then + -- Get default expression if any. If there is no declaration + -- node, it means we have an internal entity. The parent and + -- tag fields are examples of such entities. For these cases, + -- we just test the type of the entity. - End_Interp_List; + if Present (Declaration_Node (Ent)) then + Exp := Expression (Declaration_Node (Ent)); + else + Exp := Empty; + end if; - else - -- Prefix is unambiguous: mark the original prefix (which might - -- Come_From_Source) as a reference, since the new (relocated) one - -- won't be taken into account. + -- A component has PI if it has no default expression and the + -- component type has PI. - if Is_Entity_Name (New_Prefix) then - Ent := Entity (New_Prefix); + if No (Exp) then + if not Has_Preelaborable_Initialization (Etype (Ent)) then + Has_PE := False; + exit; + end if; - -- For a retrieval of a subcomponent of some composite object, - -- retrieve the ultimate entity if there is one. + -- Require the default expression to be preelaborable - elsif Nkind (New_Prefix) = N_Selected_Component - or else Nkind (New_Prefix) = N_Indexed_Component - then - Pref := Prefix (New_Prefix); + elsif not Is_Preelaborable_Expression (Exp) then + Has_PE := False; + exit; + end if; + end if; - while Present (Pref) - and then - (Nkind (Pref) = N_Selected_Component - or else Nkind (Pref) = N_Indexed_Component) - loop - Pref := Prefix (Pref); - end loop; + Next_Entity (Ent); + end loop; + end Check_Components; - if Present (Pref) and then Is_Entity_Name (Pref) then - Ent := Entity (Pref); - end if; - end if; + -- Start of processing for Has_Preelaborable_Initialization - if Present (Ent) then - Generate_Reference (Ent, New_Prefix); - end if; + begin + -- Immediate return if already marked as known preelaborable init. This + -- covers types for which this function has already been called once + -- and returned True (in which case the result is cached), and also + -- types to which a pragma Preelaborable_Initialization applies. + + if Known_To_Have_Preelab_Init (E) then + return True; end if; - end Insert_Explicit_Dereference; - ------------------- - -- Is_AAMP_Float -- - ------------------- + -- If the type is a subtype representing a generic actual type, then + -- test whether its base type has preelaborable initialization since + -- the subtype representing the actual does not inherit this attribute + -- from the actual or formal. (but maybe it should???) - function Is_AAMP_Float (E : Entity_Id) return Boolean is - begin - pragma Assert (Is_Type (E)); + if Is_Generic_Actual_Type (E) then + return Has_Preelaborable_Initialization (Base_Type (E)); + end if; - return AAMP_On_Target - and then Is_Floating_Point_Type (E) - and then E = Base_Type (E); - end Is_AAMP_Float; + -- All elementary types have preelaborable initialization - ------------------------- - -- Is_Actual_Parameter -- - ------------------------- + if Is_Elementary_Type (E) then + Has_PE := True; - function Is_Actual_Parameter (N : Node_Id) return Boolean is - PK : constant Node_Kind := Nkind (Parent (N)); + -- Array types have PI if the component type has PI - begin - case PK is - when N_Parameter_Association => - return N = Explicit_Actual_Parameter (Parent (N)); + elsif Is_Array_Type (E) then + Has_PE := Has_Preelaborable_Initialization (Component_Type (E)); - when N_Function_Call | N_Procedure_Call_Statement => - return Is_List_Member (N) - and then - List_Containing (N) = Parameter_Associations (Parent (N)); + -- A derived type has preelaborable initialization if its parent type + -- has preelaborable initialization and (in the case of a derived record + -- extension) if the non-inherited components all have preelaborable + -- initialization. However, a user-defined controlled type with an + -- overriding Initialize procedure does not have preelaborable + -- initialization. - when others => + elsif Is_Derived_Type (E) then + + -- If the derived type is a private extension then it doesn't have + -- preelaborable initialization. + + if Ekind (Base_Type (E)) = E_Record_Type_With_Private then return False; - end case; - end Is_Actual_Parameter; + end if; - --------------------- - -- Is_Aliased_View -- - --------------------- + -- First check whether ancestor type has preelaborable initialization - function Is_Aliased_View (Obj : Node_Id) return Boolean is - E : Entity_Id; + Has_PE := Has_Preelaborable_Initialization (Etype (Base_Type (E))); - begin - if Is_Entity_Name (Obj) then + -- If OK, check extension components (if any) - E := Entity (Obj); + if Has_PE and then Is_Record_Type (E) then + Check_Components (First_Entity (E)); + end if; - return - (Is_Object (E) - and then - (Is_Aliased (E) - or else (Present (Renamed_Object (E)) - and then Is_Aliased_View (Renamed_Object (E))))) + -- Check specifically for 10.2.1(11.4/2) exception: a controlled type + -- with a user defined Initialize procedure does not have PI. - or else ((Is_Formal (E) - or else Ekind (E) = E_Generic_In_Out_Parameter - or else Ekind (E) = E_Generic_In_Parameter) - and then Is_Tagged_Type (Etype (E))) + if Has_PE + and then Is_Controlled (E) + and then Has_Overriding_Initialize (E) + then + Has_PE := False; + end if; - or else ((Ekind (E) = E_Task_Type - or else Ekind (E) = E_Protected_Type) - and then In_Open_Scopes (E)) + -- Private types not derived from a type having preelaborable init and + -- that are not marked with pragma Preelaborable_Initialization do not + -- have preelaborable initialization. - -- Current instance of type + elsif Is_Private_Type (E) then + return False; - or else (Is_Type (E) and then E = Current_Scope) - or else (Is_Incomplete_Or_Private_Type (E) - and then Full_View (E) = Current_Scope); + -- Record type has PI if it is non private and all components have PI - elsif Nkind (Obj) = N_Selected_Component then - return Is_Aliased (Entity (Selector_Name (Obj))); + elsif Is_Record_Type (E) then + Has_PE := True; + Check_Components (First_Entity (E)); - elsif Nkind (Obj) = N_Indexed_Component then - return Has_Aliased_Components (Etype (Prefix (Obj))) - or else - (Is_Access_Type (Etype (Prefix (Obj))) - and then - Has_Aliased_Components - (Designated_Type (Etype (Prefix (Obj))))); + -- Protected types must not have entries, and components must meet + -- same set of rules as for record components. - elsif Nkind (Obj) = N_Unchecked_Type_Conversion - or else Nkind (Obj) = N_Type_Conversion - then - return Is_Tagged_Type (Etype (Obj)) - and then Is_Aliased_View (Expression (Obj)); + elsif Is_Protected_Type (E) then + if Has_Entries (E) then + Has_PE := False; + else + Has_PE := True; + Check_Components (First_Entity (E)); + Check_Components (First_Private_Entity (E)); + end if; - elsif Nkind (Obj) = N_Explicit_Dereference then - return Nkind (Original_Node (Obj)) /= N_Function_Call; + -- Type System.Address always has preelaborable initialization + + elsif Is_RTE (E, RE_Address) then + Has_PE := True; + + -- In all other cases, type does not have preelaborable initialization else return False; end if; - end Is_Aliased_View; - ------------------------- - -- Is_Ancestor_Package -- - ------------------------- + -- If type has preelaborable initialization, cache result - function Is_Ancestor_Package - (E1 : Entity_Id; - E2 : Entity_Id) return Boolean - is - Par : Entity_Id; + if Has_PE then + Set_Known_To_Have_Preelab_Init (E); + end if; - begin - Par := E2; - while Present (Par) - and then Par /= Standard_Standard - loop - if Par = E1 then - return True; - end if; + return Has_PE; + end Has_Preelaborable_Initialization; - Par := Scope (Par); - end loop; + --------------------------- + -- Has_Private_Component -- + --------------------------- - return False; - end Is_Ancestor_Package; - - ---------------------- - -- Is_Atomic_Object -- - ---------------------- - - function Is_Atomic_Object (N : Node_Id) return Boolean is - - function Object_Has_Atomic_Components (N : Node_Id) return Boolean; - -- Determines if given object has atomic components - - function Is_Atomic_Prefix (N : Node_Id) return Boolean; - -- If prefix is an implicit dereference, examine designated type + function Has_Private_Component (Type_Id : Entity_Id) return Boolean is + Btype : Entity_Id := Base_Type (Type_Id); + Component : Entity_Id; - function Is_Atomic_Prefix (N : Node_Id) return Boolean is - begin - if Is_Access_Type (Etype (N)) then - return - Has_Atomic_Components (Designated_Type (Etype (N))); - else - return Object_Has_Atomic_Components (N); - end if; - end Is_Atomic_Prefix; + begin + if Error_Posted (Type_Id) + or else Error_Posted (Btype) + then + return False; + end if; - function Object_Has_Atomic_Components (N : Node_Id) return Boolean is - begin - if Has_Atomic_Components (Etype (N)) - or else Is_Atomic (Etype (N)) - then - return True; + if Is_Class_Wide_Type (Btype) then + Btype := Root_Type (Btype); + end if; - elsif Is_Entity_Name (N) - and then (Has_Atomic_Components (Entity (N)) - or else Is_Atomic (Entity (N))) - then - return True; + if Is_Private_Type (Btype) then + declare + UT : constant Entity_Id := Underlying_Type (Btype); + begin + if No (UT) then + if No (Full_View (Btype)) then + return not Is_Generic_Type (Btype) + and then not Is_Generic_Type (Root_Type (Btype)); + else + return not Is_Generic_Type (Root_Type (Full_View (Btype))); + end if; + else + return not Is_Frozen (UT) and then Has_Private_Component (UT); + end if; + end; - elsif Nkind (N) = N_Indexed_Component - or else Nkind (N) = N_Selected_Component - then - return Is_Atomic_Prefix (Prefix (N)); + elsif Is_Array_Type (Btype) then + return Has_Private_Component (Component_Type (Btype)); - else - return False; - end if; - end Object_Has_Atomic_Components; + elsif Is_Record_Type (Btype) then + Component := First_Component (Btype); + while Present (Component) loop + if Has_Private_Component (Etype (Component)) then + return True; + end if; - -- Start of processing for Is_Atomic_Object + Next_Component (Component); + end loop; - begin - if Is_Atomic (Etype (N)) - or else (Is_Entity_Name (N) and then Is_Atomic (Entity (N))) - then - return True; + return False; - elsif Nkind (N) = N_Indexed_Component - or else Nkind (N) = N_Selected_Component + elsif Is_Protected_Type (Btype) + and then Present (Corresponding_Record_Type (Btype)) then - return Is_Atomic_Prefix (Prefix (N)); + return Has_Private_Component (Corresponding_Record_Type (Btype)); else return False; end if; - end Is_Atomic_Object; - - ---------------------------------------------- - -- Is_Dependent_Component_Of_Mutable_Object -- - ---------------------------------------------- + end Has_Private_Component; - function Is_Dependent_Component_Of_Mutable_Object - (Object : Node_Id) return Boolean - is - P : Node_Id; - Prefix_Type : Entity_Id; - P_Aliased : Boolean := False; - Comp : Entity_Id; + ---------------- + -- Has_Stream -- + ---------------- - function Is_Declared_Within_Variant (Comp : Entity_Id) return Boolean; - -- Returns True if and only if Comp is declared within a variant part + function Has_Stream (T : Entity_Id) return Boolean is + E : Entity_Id; - -------------------------------- - -- Is_Declared_Within_Variant -- - -------------------------------- + begin + if No (T) then + return False; - function Is_Declared_Within_Variant (Comp : Entity_Id) return Boolean is - Comp_Decl : constant Node_Id := Parent (Comp); - Comp_List : constant Node_Id := Parent (Comp_Decl); + elsif Is_RTE (Root_Type (T), RE_Root_Stream_Type) then + return True; - begin - return Nkind (Parent (Comp_List)) = N_Variant; - end Is_Declared_Within_Variant; + elsif Is_Array_Type (T) then + return Has_Stream (Component_Type (T)); - -- Start of processing for Is_Dependent_Component_Of_Mutable_Object + elsif Is_Record_Type (T) then + E := First_Component (T); + while Present (E) loop + if Has_Stream (Etype (E)) then + return True; + else + Next_Component (E); + end if; + end loop; - begin - if Is_Variable (Object) then + return False; - if Nkind (Object) = N_Selected_Component then - P := Prefix (Object); - Prefix_Type := Etype (P); + elsif Is_Private_Type (T) then + return Has_Stream (Underlying_Type (T)); - if Is_Entity_Name (P) then + else + return False; + end if; + end Has_Stream; - if Ekind (Entity (P)) = E_Generic_In_Out_Parameter then - Prefix_Type := Base_Type (Prefix_Type); - end if; + -------------------------- + -- Has_Tagged_Component -- + -------------------------- - if Is_Aliased (Entity (P)) then - P_Aliased := True; - end if; + function Has_Tagged_Component (Typ : Entity_Id) return Boolean is + Comp : Entity_Id; - -- A discriminant check on a selected component may be - -- expanded into a dereference when removing side-effects. - -- Recover the original node and its type, which may be - -- unconstrained. + begin + if Is_Private_Type (Typ) + and then Present (Underlying_Type (Typ)) + then + return Has_Tagged_Component (Underlying_Type (Typ)); - elsif Nkind (P) = N_Explicit_Dereference - and then not (Comes_From_Source (P)) - then - P := Original_Node (P); - Prefix_Type := Etype (P); + elsif Is_Array_Type (Typ) then + return Has_Tagged_Component (Component_Type (Typ)); - else - -- Check for prefix being an aliased component ??? - null; + elsif Is_Tagged_Type (Typ) then + return True; + elsif Is_Record_Type (Typ) then + Comp := First_Component (Typ); + while Present (Comp) loop + if Has_Tagged_Component (Etype (Comp)) then + return True; end if; - -- A heap object is constrained by its initial value - - -- Ada 2005 AI-363:if the designated type is a type with a - -- constrained partial view, the resulting heap object is not - -- constrained, and a renaming of the component is now unsafe. + Comp := Next_Component (Typ); + end loop; - if Is_Access_Type (Prefix_Type) - and then - not Has_Constrained_Partial_View - (Designated_Type (Prefix_Type)) - then - return False; + return False; - elsif Nkind (P) = N_Explicit_Dereference - and then not Has_Constrained_Partial_View (Prefix_Type) - then - return False; - end if; + else + return False; + end if; + end Has_Tagged_Component; - Comp := - Original_Record_Component (Entity (Selector_Name (Object))); + -------------------------- + -- Implements_Interface -- + -------------------------- - -- As per AI-0017, the renaming is illegal in a generic body, - -- even if the subtype is indefinite. + function Implements_Interface + (Typ_Ent : Entity_Id; + Iface_Ent : Entity_Id; + Exclude_Parents : Boolean := False) return Boolean + is + Ifaces_List : Elist_Id; + Elmt : Elmt_Id; + Iface : Entity_Id; + Typ : Entity_Id; - if not Is_Constrained (Prefix_Type) - and then (not Is_Indefinite_Subtype (Prefix_Type) - or else - (Is_Generic_Type (Prefix_Type) - and then Ekind (Current_Scope) = E_Generic_Package - and then In_Package_Body (Current_Scope))) + begin + if Is_Class_Wide_Type (Typ_Ent) then + Typ := Etype (Typ_Ent); + else + Typ := Typ_Ent; + end if; - and then (Is_Declared_Within_Variant (Comp) - or else Has_Discriminant_Dependent_Constraint (Comp)) - and then not P_Aliased - then - return True; + if Is_Class_Wide_Type (Iface_Ent) then + Iface := Etype (Iface_Ent); + else + Iface := Iface_Ent; + end if; - else - return - Is_Dependent_Component_Of_Mutable_Object (Prefix (Object)); + if not Has_Interfaces (Typ) then + return False; + end if; - end if; + Collect_Interfaces (Typ, Ifaces_List); - elsif Nkind (Object) = N_Indexed_Component - or else Nkind (Object) = N_Slice + Elmt := First_Elmt (Ifaces_List); + while Present (Elmt) loop + if Is_Ancestor (Node (Elmt), Typ) + and then Exclude_Parents then - return Is_Dependent_Component_Of_Mutable_Object (Prefix (Object)); - - -- A type conversion that Is_Variable is a view conversion: - -- go back to the denoted object. + null; - elsif Nkind (Object) = N_Type_Conversion then - return - Is_Dependent_Component_Of_Mutable_Object (Expression (Object)); + elsif Node (Elmt) = Iface then + return True; end if; - end if; + + Next_Elmt (Elmt); + end loop; return False; - end Is_Dependent_Component_Of_Mutable_Object; + end Implements_Interface; - --------------------- - -- Is_Dereferenced -- - --------------------- + ----------------- + -- In_Instance -- + ----------------- + + function In_Instance return Boolean is + Curr_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit); + S : Entity_Id; - function Is_Dereferenced (N : Node_Id) return Boolean is - P : constant Node_Id := Parent (N); begin - return - (Nkind (P) = N_Selected_Component - or else - Nkind (P) = N_Explicit_Dereference - or else - Nkind (P) = N_Indexed_Component - or else - Nkind (P) = N_Slice) - and then Prefix (P) = N; - end Is_Dereferenced; + S := Current_Scope; + while Present (S) + and then S /= Standard_Standard + loop + if (Ekind (S) = E_Function + or else Ekind (S) = E_Package + or else Ekind (S) = E_Procedure) + and then Is_Generic_Instance (S) + then + -- A child instance is always compiled in the context of a parent + -- instance. Nevertheless, the actuals are not analyzed in an + -- instance context. We detect this case by examining the current + -- compilation unit, which must be a child instance, and checking + -- that it is not currently on the scope stack. + + if Is_Child_Unit (Curr_Unit) + and then + Nkind (Unit (Cunit (Current_Sem_Unit))) + = N_Package_Instantiation + and then not In_Open_Scopes (Curr_Unit) + then + return False; + else + return True; + end if; + end if; + + S := Scope (S); + end loop; + + return False; + end In_Instance; ---------------------- - -- Is_Descendent_Of -- + -- In_Instance_Body -- ---------------------- - function Is_Descendent_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean is - T : Entity_Id; - Etyp : Entity_Id; + function In_Instance_Body return Boolean is + S : Entity_Id; + + begin + S := Current_Scope; + while Present (S) + and then S /= Standard_Standard + loop + if (Ekind (S) = E_Function + or else Ekind (S) = E_Procedure) + and then Is_Generic_Instance (S) + then + return True; + + elsif Ekind (S) = E_Package + and then In_Package_Body (S) + and then Is_Generic_Instance (S) + then + return True; + end if; + + S := Scope (S); + end loop; + + return False; + end In_Instance_Body; + + ----------------------------- + -- In_Instance_Not_Visible -- + ----------------------------- + + function In_Instance_Not_Visible return Boolean is + S : Entity_Id; + + begin + S := Current_Scope; + while Present (S) + and then S /= Standard_Standard + loop + if (Ekind (S) = E_Function + or else Ekind (S) = E_Procedure) + and then Is_Generic_Instance (S) + then + return True; + + elsif Ekind (S) = E_Package + and then (In_Package_Body (S) or else In_Private_Part (S)) + and then Is_Generic_Instance (S) + then + return True; + end if; + + S := Scope (S); + end loop; + + return False; + end In_Instance_Not_Visible; + + ------------------------------ + -- In_Instance_Visible_Part -- + ------------------------------ + + function In_Instance_Visible_Part return Boolean is + S : Entity_Id; + + begin + S := Current_Scope; + while Present (S) + and then S /= Standard_Standard + loop + if Ekind (S) = E_Package + and then Is_Generic_Instance (S) + and then not In_Package_Body (S) + and then not In_Private_Part (S) + then + return True; + end if; + + S := Scope (S); + end loop; + + return False; + end In_Instance_Visible_Part; + + --------------------- + -- In_Package_Body -- + --------------------- + + function In_Package_Body return Boolean is + S : Entity_Id; + + begin + S := Current_Scope; + while Present (S) + and then S /= Standard_Standard + loop + if Ekind (S) = E_Package + and then In_Package_Body (S) + then + return True; + else + S := Scope (S); + end if; + end loop; + + return False; + end In_Package_Body; + + -------------------------------- + -- In_Parameter_Specification -- + -------------------------------- + + function In_Parameter_Specification (N : Node_Id) return Boolean is + PN : Node_Id; + + begin + PN := Parent (N); + while Present (PN) loop + if Nkind (PN) = N_Parameter_Specification then + return True; + end if; + + PN := Parent (PN); + end loop; + + return False; + end In_Parameter_Specification; + + -------------------------------------- + -- In_Subprogram_Or_Concurrent_Unit -- + -------------------------------------- + + function In_Subprogram_Or_Concurrent_Unit return Boolean is + E : Entity_Id; + K : Entity_Kind; + + begin + -- Use scope chain to check successively outer scopes + + E := Current_Scope; + loop + K := Ekind (E); + + if K in Subprogram_Kind + or else K in Concurrent_Kind + or else K in Generic_Subprogram_Kind + then + return True; + + elsif E = Standard_Standard then + return False; + end if; + + E := Scope (E); + end loop; + end In_Subprogram_Or_Concurrent_Unit; + + --------------------- + -- In_Visible_Part -- + --------------------- + + function In_Visible_Part (Scope_Id : Entity_Id) return Boolean is + begin + return + Is_Package_Or_Generic_Package (Scope_Id) + and then In_Open_Scopes (Scope_Id) + and then not In_Package_Body (Scope_Id) + and then not In_Private_Part (Scope_Id); + end In_Visible_Part; + + --------------------------------- + -- Insert_Explicit_Dereference -- + --------------------------------- + + procedure Insert_Explicit_Dereference (N : Node_Id) is + New_Prefix : constant Node_Id := Relocate_Node (N); + Ent : Entity_Id := Empty; + Pref : Node_Id; + I : Interp_Index; + It : Interp; + T : Entity_Id; + + begin + Save_Interps (N, New_Prefix); + Rewrite (N, + Make_Explicit_Dereference (Sloc (N), + Prefix => New_Prefix)); + + Set_Etype (N, Designated_Type (Etype (New_Prefix))); + + if Is_Overloaded (New_Prefix) then + + -- The deference is also overloaded, and its interpretations are the + -- designated types of the interpretations of the original node. + + Set_Etype (N, Any_Type); + + Get_First_Interp (New_Prefix, I, It); + while Present (It.Nam) loop + T := It.Typ; + + if Is_Access_Type (T) then + Add_One_Interp (N, Designated_Type (T), Designated_Type (T)); + end if; + + Get_Next_Interp (I, It); + end loop; + + End_Interp_List; + + else + -- Prefix is unambiguous: mark the original prefix (which might + -- Come_From_Source) as a reference, since the new (relocated) one + -- won't be taken into account. + + if Is_Entity_Name (New_Prefix) then + Ent := Entity (New_Prefix); + + -- For a retrieval of a subcomponent of some composite object, + -- retrieve the ultimate entity if there is one. + + elsif Nkind (New_Prefix) = N_Selected_Component + or else Nkind (New_Prefix) = N_Indexed_Component + then + Pref := Prefix (New_Prefix); + while Present (Pref) + and then + (Nkind (Pref) = N_Selected_Component + or else Nkind (Pref) = N_Indexed_Component) + loop + Pref := Prefix (Pref); + end loop; + + if Present (Pref) and then Is_Entity_Name (Pref) then + Ent := Entity (Pref); + end if; + end if; + + if Present (Ent) then + Generate_Reference (Ent, New_Prefix); + end if; + end if; + end Insert_Explicit_Dereference; + + ------------------------------------------ + -- Inspect_Deferred_Constant_Completion -- + ------------------------------------------ + + procedure Inspect_Deferred_Constant_Completion (Decls : List_Id) is + Decl : Node_Id; + + begin + Decl := First (Decls); + while Present (Decl) loop + + -- Deferred constant signature + + if Nkind (Decl) = N_Object_Declaration + and then Constant_Present (Decl) + and then No (Expression (Decl)) + + -- No need to check internally generated constants + + and then Comes_From_Source (Decl) + + -- The constant is not completed. A full object declaration + -- or a pragma Import complete a deferred constant. + + and then not Has_Completion (Defining_Identifier (Decl)) + then + Error_Msg_N + ("constant declaration requires initialization expression", + Defining_Identifier (Decl)); + end if; + + Decl := Next (Decl); + end loop; + end Inspect_Deferred_Constant_Completion; + + ------------------- + -- Is_AAMP_Float -- + ------------------- + + function Is_AAMP_Float (E : Entity_Id) return Boolean is + pragma Assert (Is_Type (E)); + begin + return AAMP_On_Target + and then Is_Floating_Point_Type (E) + and then E = Base_Type (E); + end Is_AAMP_Float; + + ------------------------- + -- Is_Actual_Parameter -- + ------------------------- + + function Is_Actual_Parameter (N : Node_Id) return Boolean is + PK : constant Node_Kind := Nkind (Parent (N)); + + begin + case PK is + when N_Parameter_Association => + return N = Explicit_Actual_Parameter (Parent (N)); + + when N_Function_Call | N_Procedure_Call_Statement => + return Is_List_Member (N) + and then + List_Containing (N) = Parameter_Associations (Parent (N)); + + when others => + return False; + end case; + end Is_Actual_Parameter; + + --------------------- + -- Is_Aliased_View -- + --------------------- + + function Is_Aliased_View (Obj : Node_Id) return Boolean is + E : Entity_Id; + + begin + if Is_Entity_Name (Obj) then + + E := Entity (Obj); + + return + (Is_Object (E) + and then + (Is_Aliased (E) + or else (Present (Renamed_Object (E)) + and then Is_Aliased_View (Renamed_Object (E))))) + + or else ((Is_Formal (E) + or else Ekind (E) = E_Generic_In_Out_Parameter + or else Ekind (E) = E_Generic_In_Parameter) + and then Is_Tagged_Type (Etype (E))) + + or else (Is_Concurrent_Type (E) + and then In_Open_Scopes (E)) + + -- Current instance of type, either directly or as rewritten + -- reference to the current object. + + or else (Is_Entity_Name (Original_Node (Obj)) + and then Present (Entity (Original_Node (Obj))) + and then Is_Type (Entity (Original_Node (Obj)))) + + or else (Is_Type (E) and then E = Current_Scope) + + or else (Is_Incomplete_Or_Private_Type (E) + and then Full_View (E) = Current_Scope); + + elsif Nkind (Obj) = N_Selected_Component then + return Is_Aliased (Entity (Selector_Name (Obj))); + + elsif Nkind (Obj) = N_Indexed_Component then + return Has_Aliased_Components (Etype (Prefix (Obj))) + or else + (Is_Access_Type (Etype (Prefix (Obj))) + and then + Has_Aliased_Components + (Designated_Type (Etype (Prefix (Obj))))); + + elsif Nkind (Obj) = N_Unchecked_Type_Conversion + or else Nkind (Obj) = N_Type_Conversion + then + return Is_Tagged_Type (Etype (Obj)) + and then Is_Aliased_View (Expression (Obj)); + + elsif Nkind (Obj) = N_Explicit_Dereference then + return Nkind (Original_Node (Obj)) /= N_Function_Call; + + else + return False; + end if; + end Is_Aliased_View; + + ------------------------- + -- Is_Ancestor_Package -- + ------------------------- + + function Is_Ancestor_Package + (E1 : Entity_Id; + E2 : Entity_Id) return Boolean + is + Par : Entity_Id; + + begin + Par := E2; + while Present (Par) + and then Par /= Standard_Standard + loop + if Par = E1 then + return True; + end if; + + Par := Scope (Par); + end loop; + + return False; + end Is_Ancestor_Package; + + ---------------------- + -- Is_Atomic_Object -- + ---------------------- + + function Is_Atomic_Object (N : Node_Id) return Boolean is + + function Object_Has_Atomic_Components (N : Node_Id) return Boolean; + -- Determines if given object has atomic components + + function Is_Atomic_Prefix (N : Node_Id) return Boolean; + -- If prefix is an implicit dereference, examine designated type + + ---------------------- + -- Is_Atomic_Prefix -- + ---------------------- + + function Is_Atomic_Prefix (N : Node_Id) return Boolean is + begin + if Is_Access_Type (Etype (N)) then + return + Has_Atomic_Components (Designated_Type (Etype (N))); + else + return Object_Has_Atomic_Components (N); + end if; + end Is_Atomic_Prefix; + + ---------------------------------- + -- Object_Has_Atomic_Components -- + ---------------------------------- + + function Object_Has_Atomic_Components (N : Node_Id) return Boolean is + begin + if Has_Atomic_Components (Etype (N)) + or else Is_Atomic (Etype (N)) + then + return True; + + elsif Is_Entity_Name (N) + and then (Has_Atomic_Components (Entity (N)) + or else Is_Atomic (Entity (N))) + then + return True; + + elsif Nkind (N) = N_Indexed_Component + or else Nkind (N) = N_Selected_Component + then + return Is_Atomic_Prefix (Prefix (N)); + + else + return False; + end if; + end Object_Has_Atomic_Components; + + -- Start of processing for Is_Atomic_Object + + begin + if Is_Atomic (Etype (N)) + or else (Is_Entity_Name (N) and then Is_Atomic (Entity (N))) + then + return True; + + elsif Nkind (N) = N_Indexed_Component + or else Nkind (N) = N_Selected_Component + then + return Is_Atomic_Prefix (Prefix (N)); + + else + return False; + end if; + end Is_Atomic_Object; + + ------------------------- + -- Is_Coextension_Root -- + ------------------------- + + function Is_Coextension_Root (N : Node_Id) return Boolean is + begin + return + Nkind (N) = N_Allocator + and then Present (Coextensions (N)) + + -- Anonymous access discriminants carry a list of all nested + -- controlled coextensions. + + and then not Is_Dynamic_Coextension (N) + and then not Is_Static_Coextension (N); + end Is_Coextension_Root; + + ----------------------------- + -- Is_Concurrent_Interface -- + ----------------------------- + + function Is_Concurrent_Interface (T : Entity_Id) return Boolean is + begin + return + Is_Interface (T) + and then + (Is_Protected_Interface (T) + or else Is_Synchronized_Interface (T) + or else Is_Task_Interface (T)); + end Is_Concurrent_Interface; + + -------------------------------------- + -- Is_Controlling_Limited_Procedure -- + -------------------------------------- + + function Is_Controlling_Limited_Procedure + (Proc_Nam : Entity_Id) return Boolean + is + Param_Typ : Entity_Id := Empty; + + begin + if Ekind (Proc_Nam) = E_Procedure + and then Present (Parameter_Specifications (Parent (Proc_Nam))) + then + Param_Typ := Etype (Parameter_Type (First ( + Parameter_Specifications (Parent (Proc_Nam))))); + + -- In this case where an Itype was created, the procedure call has been + -- rewritten. + + elsif Present (Associated_Node_For_Itype (Proc_Nam)) + and then Present (Original_Node (Associated_Node_For_Itype (Proc_Nam))) + and then + Present (Parameter_Associations + (Associated_Node_For_Itype (Proc_Nam))) + then + Param_Typ := + Etype (First (Parameter_Associations + (Associated_Node_For_Itype (Proc_Nam)))); + end if; + + if Present (Param_Typ) then + return + Is_Interface (Param_Typ) + and then Is_Limited_Record (Param_Typ); + end if; + + return False; + end Is_Controlling_Limited_Procedure; + + ---------------------------------------------- + -- Is_Dependent_Component_Of_Mutable_Object -- + ---------------------------------------------- + + function Is_Dependent_Component_Of_Mutable_Object + (Object : Node_Id) return Boolean + is + P : Node_Id; + Prefix_Type : Entity_Id; + P_Aliased : Boolean := False; + Comp : Entity_Id; + + function Is_Declared_Within_Variant (Comp : Entity_Id) return Boolean; + -- Returns True if and only if Comp is declared within a variant part + + -------------------------------- + -- Is_Declared_Within_Variant -- + -------------------------------- + + function Is_Declared_Within_Variant (Comp : Entity_Id) return Boolean is + Comp_Decl : constant Node_Id := Parent (Comp); + Comp_List : constant Node_Id := Parent (Comp_Decl); + begin + return Nkind (Parent (Comp_List)) = N_Variant; + end Is_Declared_Within_Variant; + + -- Start of processing for Is_Dependent_Component_Of_Mutable_Object + + begin + if Is_Variable (Object) then + + if Nkind (Object) = N_Selected_Component then + P := Prefix (Object); + Prefix_Type := Etype (P); + + if Is_Entity_Name (P) then + + if Ekind (Entity (P)) = E_Generic_In_Out_Parameter then + Prefix_Type := Base_Type (Prefix_Type); + end if; + + if Is_Aliased (Entity (P)) then + P_Aliased := True; + end if; + + -- A discriminant check on a selected component may be + -- expanded into a dereference when removing side-effects. + -- Recover the original node and its type, which may be + -- unconstrained. + + elsif Nkind (P) = N_Explicit_Dereference + and then not (Comes_From_Source (P)) + then + P := Original_Node (P); + Prefix_Type := Etype (P); + + else + -- Check for prefix being an aliased component ??? + null; + + end if; + + -- A heap object is constrained by its initial value + + -- Ada 2005 (AI-363): Always assume the object could be mutable in + -- the dereferenced case, since the access value might denote an + -- unconstrained aliased object, whereas in Ada 95 the designated + -- object is guaranteed to be constrained. A worst-case assumption + -- has to apply in Ada 2005 because we can't tell at compile time + -- whether the object is "constrained by its initial value" + -- (despite the fact that 3.10.2(26/2) and 8.5.1(5/2) are + -- semantic rules -- these rules are acknowledged to need fixing). + + if Ada_Version < Ada_05 then + if Is_Access_Type (Prefix_Type) + or else Nkind (P) = N_Explicit_Dereference + then + return False; + end if; + + elsif Ada_Version >= Ada_05 then + if Is_Access_Type (Prefix_Type) then + + -- If the access type is pool-specific, and there is no + -- constrained partial view of the designated type, then the + -- designated object is known to be constrained. + + if Ekind (Prefix_Type) = E_Access_Type + and then not Has_Constrained_Partial_View + (Designated_Type (Prefix_Type)) + then + return False; + + -- Otherwise (general access type, or there is a constrained + -- partial view of the designated type), we need to check + -- based on the designated type. + + else + Prefix_Type := Designated_Type (Prefix_Type); + end if; + end if; + end if; + + Comp := + Original_Record_Component (Entity (Selector_Name (Object))); + + -- As per AI-0017, the renaming is illegal in a generic body, + -- even if the subtype is indefinite. + + -- Ada 2005 (AI-363): In Ada 2005 an aliased object can be mutable + + if not Is_Constrained (Prefix_Type) + and then (not Is_Indefinite_Subtype (Prefix_Type) + or else + (Is_Generic_Type (Prefix_Type) + and then Ekind (Current_Scope) = E_Generic_Package + and then In_Package_Body (Current_Scope))) + + and then (Is_Declared_Within_Variant (Comp) + or else Has_Discriminant_Dependent_Constraint (Comp)) + and then (not P_Aliased or else Ada_Version >= Ada_05) + then + return True; + + else + return + Is_Dependent_Component_Of_Mutable_Object (Prefix (Object)); + + end if; + + elsif Nkind (Object) = N_Indexed_Component + or else Nkind (Object) = N_Slice + then + return Is_Dependent_Component_Of_Mutable_Object (Prefix (Object)); + + -- A type conversion that Is_Variable is a view conversion: + -- go back to the denoted object. + + elsif Nkind (Object) = N_Type_Conversion then + return + Is_Dependent_Component_Of_Mutable_Object (Expression (Object)); + end if; + end if; + + return False; + end Is_Dependent_Component_Of_Mutable_Object; + + --------------------- + -- Is_Dereferenced -- + --------------------- + + function Is_Dereferenced (N : Node_Id) return Boolean is + P : constant Node_Id := Parent (N); + begin + return + (Nkind (P) = N_Selected_Component + or else + Nkind (P) = N_Explicit_Dereference + or else + Nkind (P) = N_Indexed_Component + or else + Nkind (P) = N_Slice) + and then Prefix (P) = N; + end Is_Dereferenced; + + ---------------------- + -- Is_Descendent_Of -- + ---------------------- + + function Is_Descendent_Of (T1 : Entity_Id; T2 : Entity_Id) return Boolean is + T : Entity_Id; + Etyp : Entity_Id; + + begin + pragma Assert (Nkind (T1) in N_Entity); + pragma Assert (Nkind (T2) in N_Entity); + + T := Base_Type (T1); + + -- Immediate return if the types match + + if T = T2 then + return True; + + -- Comment needed here ??? + + elsif Ekind (T) = E_Class_Wide_Type then + return Etype (T) = T2; + + -- All other cases + + else + loop + Etyp := Etype (T); + + -- Done if we found the type we are looking for + + if Etyp = T2 then + return True; + + -- Done if no more derivations to check + + elsif T = T1 + or else T = Etyp + then + return False; + + -- Following test catches error cases resulting from prev errors + + elsif No (Etyp) then + return False; + + elsif Is_Private_Type (T) and then Etyp = Full_View (T) then + return False; + + elsif Is_Private_Type (Etyp) and then Full_View (Etyp) = T then + return False; + end if; + + T := Base_Type (Etyp); + end loop; + end if; + end Is_Descendent_Of; + + -------------- + -- Is_False -- + -------------- + + function Is_False (U : Uint) return Boolean is + begin + return (U = 0); + end Is_False; + + --------------------------- + -- Is_Fixed_Model_Number -- + --------------------------- + + function Is_Fixed_Model_Number (U : Ureal; T : Entity_Id) return Boolean is + S : constant Ureal := Small_Value (T); + M : Urealp.Save_Mark; + R : Boolean; + begin + M := Urealp.Mark; + R := (U = UR_Trunc (U / S) * S); + Urealp.Release (M); + return R; + end Is_Fixed_Model_Number; + + ------------------------------- + -- Is_Fully_Initialized_Type -- + ------------------------------- + + function Is_Fully_Initialized_Type (Typ : Entity_Id) return Boolean is + begin + if Is_Scalar_Type (Typ) then + return False; + + elsif Is_Access_Type (Typ) then + return True; + + elsif Is_Array_Type (Typ) then + if Is_Fully_Initialized_Type (Component_Type (Typ)) then + return True; + end if; + + -- An interesting case, if we have a constrained type one of whose + -- bounds is known to be null, then there are no elements to be + -- initialized, so all the elements are initialized! + + if Is_Constrained (Typ) then + declare + Indx : Node_Id; + Indx_Typ : Entity_Id; + Lbd, Hbd : Node_Id; + + begin + Indx := First_Index (Typ); + while Present (Indx) loop + if Etype (Indx) = Any_Type then + return False; + + -- If index is a range, use directly + + elsif Nkind (Indx) = N_Range then + Lbd := Low_Bound (Indx); + Hbd := High_Bound (Indx); + + else + Indx_Typ := Etype (Indx); + + if Is_Private_Type (Indx_Typ) then + Indx_Typ := Full_View (Indx_Typ); + end if; + + if No (Indx_Typ) or else Etype (Indx_Typ) = Any_Type then + return False; + else + Lbd := Type_Low_Bound (Indx_Typ); + Hbd := Type_High_Bound (Indx_Typ); + end if; + end if; + + if Compile_Time_Known_Value (Lbd) + and then Compile_Time_Known_Value (Hbd) + then + if Expr_Value (Hbd) < Expr_Value (Lbd) then + return True; + end if; + end if; + + Next_Index (Indx); + end loop; + end; + end if; + + -- If no null indexes, then type is not fully initialized + + return False; + + -- Record types + + elsif Is_Record_Type (Typ) then + if Has_Discriminants (Typ) + and then + Present (Discriminant_Default_Value (First_Discriminant (Typ))) + and then Is_Fully_Initialized_Variant (Typ) + then + return True; + end if; + + -- Controlled records are considered to be fully initialized if + -- there is a user defined Initialize routine. This may not be + -- entirely correct, but as the spec notes, we are guessing here + -- what is best from the point of view of issuing warnings. + + if Is_Controlled (Typ) then + declare + Utyp : constant Entity_Id := Underlying_Type (Typ); + + begin + if Present (Utyp) then + declare + Init : constant Entity_Id := + (Find_Prim_Op + (Underlying_Type (Typ), Name_Initialize)); + + begin + if Present (Init) + and then Comes_From_Source (Init) + and then not + Is_Predefined_File_Name + (File_Name (Get_Source_File_Index (Sloc (Init)))) + then + return True; + + elsif Has_Null_Extension (Typ) + and then + Is_Fully_Initialized_Type + (Etype (Base_Type (Typ))) + then + return True; + end if; + end; + end if; + end; + end if; + + -- Otherwise see if all record components are initialized + + declare + Ent : Entity_Id; + + begin + Ent := First_Entity (Typ); + while Present (Ent) loop + if Chars (Ent) = Name_uController then + null; + + elsif Ekind (Ent) = E_Component + and then (No (Parent (Ent)) + or else No (Expression (Parent (Ent)))) + and then not Is_Fully_Initialized_Type (Etype (Ent)) + + -- Special VM case for tag components, which need to be + -- defined in this case, but are never initialized as VMs + -- are using other dispatching mechanisms. Ignore this + -- uninitialized case. Note that this applies both to the + -- uTag entry and the main vtable pointer (CPP_Class case). + + and then (VM_Target = No_VM or else not Is_Tag (Ent)) + then + return False; + end if; + + Next_Entity (Ent); + end loop; + end; + + -- No uninitialized components, so type is fully initialized. + -- Note that this catches the case of no components as well. + + return True; + + elsif Is_Concurrent_Type (Typ) then + return True; + + elsif Is_Private_Type (Typ) then + declare + U : constant Entity_Id := Underlying_Type (Typ); + + begin + if No (U) then + return False; + else + return Is_Fully_Initialized_Type (U); + end if; + end; + + else + return False; + end if; + end Is_Fully_Initialized_Type; + + ---------------------------------- + -- Is_Fully_Initialized_Variant -- + ---------------------------------- + + function Is_Fully_Initialized_Variant (Typ : Entity_Id) return Boolean is + Loc : constant Source_Ptr := Sloc (Typ); + Constraints : constant List_Id := New_List; + Components : constant Elist_Id := New_Elmt_List; + Comp_Elmt : Elmt_Id; + Comp_Id : Node_Id; + Comp_List : Node_Id; + Discr : Entity_Id; + Discr_Val : Node_Id; + + Report_Errors : Boolean; + pragma Warnings (Off, Report_Errors); + + begin + if Serious_Errors_Detected > 0 then + return False; + end if; + + if Is_Record_Type (Typ) + and then Nkind (Parent (Typ)) = N_Full_Type_Declaration + and then Nkind (Type_Definition (Parent (Typ))) = N_Record_Definition + then + Comp_List := Component_List (Type_Definition (Parent (Typ))); + + Discr := First_Discriminant (Typ); + while Present (Discr) loop + if Nkind (Parent (Discr)) = N_Discriminant_Specification then + Discr_Val := Expression (Parent (Discr)); + + if Present (Discr_Val) + and then Is_OK_Static_Expression (Discr_Val) + then + Append_To (Constraints, + Make_Component_Association (Loc, + Choices => New_List (New_Occurrence_Of (Discr, Loc)), + Expression => New_Copy (Discr_Val))); + else + return False; + end if; + else + return False; + end if; + + Next_Discriminant (Discr); + end loop; + + Gather_Components + (Typ => Typ, + Comp_List => Comp_List, + Governed_By => Constraints, + Into => Components, + Report_Errors => Report_Errors); + + -- Check that each component present is fully initialized + + Comp_Elmt := First_Elmt (Components); + while Present (Comp_Elmt) loop + Comp_Id := Node (Comp_Elmt); + + if Ekind (Comp_Id) = E_Component + and then (No (Parent (Comp_Id)) + or else No (Expression (Parent (Comp_Id)))) + and then not Is_Fully_Initialized_Type (Etype (Comp_Id)) + then + return False; + end if; + + Next_Elmt (Comp_Elmt); + end loop; + + return True; + + elsif Is_Private_Type (Typ) then + declare + U : constant Entity_Id := Underlying_Type (Typ); + + begin + if No (U) then + return False; + else + return Is_Fully_Initialized_Variant (U); + end if; + end; + else + return False; + end if; + end Is_Fully_Initialized_Variant; + + ---------------------------- + -- Is_Inherited_Operation -- + ---------------------------- + + function Is_Inherited_Operation (E : Entity_Id) return Boolean is + Kind : constant Node_Kind := Nkind (Parent (E)); + begin + pragma Assert (Is_Overloadable (E)); + return Kind = N_Full_Type_Declaration + or else Kind = N_Private_Extension_Declaration + or else Kind = N_Subtype_Declaration + or else (Ekind (E) = E_Enumeration_Literal + and then Is_Derived_Type (Etype (E))); + end Is_Inherited_Operation; + + ----------------------------- + -- Is_Library_Level_Entity -- + ----------------------------- + + function Is_Library_Level_Entity (E : Entity_Id) return Boolean is + begin + -- The following is a small optimization, and it also properly handles + -- discriminals, which in task bodies might appear in expressions before + -- the corresponding procedure has been created, and which therefore do + -- not have an assigned scope. + + if Ekind (E) in Formal_Kind then + return False; + end if; + + -- Normal test is simply that the enclosing dynamic scope is Standard + + return Enclosing_Dynamic_Scope (E) = Standard_Standard; + end Is_Library_Level_Entity; + + --------------------------------- + -- Is_Local_Variable_Reference -- + --------------------------------- + + function Is_Local_Variable_Reference (Expr : Node_Id) return Boolean is + begin + if not Is_Entity_Name (Expr) then + return False; + + else + declare + Ent : constant Entity_Id := Entity (Expr); + Sub : constant Entity_Id := Enclosing_Subprogram (Ent); + begin + if Ekind (Ent) /= E_Variable + and then + Ekind (Ent) /= E_In_Out_Parameter + then + return False; + else + return Present (Sub) and then Sub = Current_Subprogram; + end if; + end; + end if; + end Is_Local_Variable_Reference; + + ------------------------- + -- Is_Object_Reference -- + ------------------------- + function Is_Object_Reference (N : Node_Id) return Boolean is begin - pragma Assert (Nkind (T1) in N_Entity); - pragma Assert (Nkind (T2) in N_Entity); - - T := Base_Type (T1); - - -- Immediate return if the types match + if Is_Entity_Name (N) then + return Present (Entity (N)) and then Is_Object (Entity (N)); - if T = T2 then - return True; + else + case Nkind (N) is + when N_Indexed_Component | N_Slice => + return + Is_Object_Reference (Prefix (N)) + or else Is_Access_Type (Etype (Prefix (N))); - -- Comment needed here ??? + -- In Ada95, a function call is a constant object; a procedure + -- call is not. - elsif Ekind (T) = E_Class_Wide_Type then - return Etype (T) = T2; + when N_Function_Call => + return Etype (N) /= Standard_Void_Type; - -- All other cases + -- A reference to the stream attribute Input is a function call - else - loop - Etyp := Etype (T); + when N_Attribute_Reference => + return Attribute_Name (N) = Name_Input; - -- Done if we found the type we are looking for + when N_Selected_Component => + return + Is_Object_Reference (Selector_Name (N)) + and then + (Is_Object_Reference (Prefix (N)) + or else Is_Access_Type (Etype (Prefix (N)))); - if Etyp = T2 then + when N_Explicit_Dereference => return True; - -- Done if no more derivations to check - - elsif T = T1 - or else T = Etyp - then - return False; + -- A view conversion of a tagged object is an object reference - -- Following test catches error cases resulting from prev errors + when N_Type_Conversion => + return Is_Tagged_Type (Etype (Subtype_Mark (N))) + and then Is_Tagged_Type (Etype (Expression (N))) + and then Is_Object_Reference (Expression (N)); - elsif No (Etyp) then - return False; + -- An unchecked type conversion is considered to be an object if + -- the operand is an object (this construction arises only as a + -- result of expansion activities). - elsif Is_Private_Type (T) and then Etyp = Full_View (T) then - return False; + when N_Unchecked_Type_Conversion => + return True; - elsif Is_Private_Type (Etyp) and then Full_View (Etyp) = T then + when others => return False; - end if; - - T := Base_Type (Etyp); - end loop; + end case; end if; + end Is_Object_Reference; - raise Program_Error; - end Is_Descendent_Of; - - ------------------------------ - -- Is_Descendent_Of_Address -- - ------------------------------ + ----------------------------------- + -- Is_OK_Variable_For_Out_Formal -- + ----------------------------------- - function Is_Descendent_Of_Address (T1 : Entity_Id) return Boolean is + function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean is begin - -- If Address has not been loaded, answer must be False + Note_Possible_Modification (AV, Sure => True); + + -- We must reject parenthesized variable names. The check for + -- Comes_From_Source is present because there are currently + -- cases where the compiler violates this rule (e.g. passing + -- a task object to its controlled Initialize routine). - if not RTU_Loaded (System) then + if Paren_Count (AV) > 0 and then Comes_From_Source (AV) then return False; - -- Otherwise we can get the entity we are interested in without - -- causing an unwanted dependency on System, and do the test. + -- A variable is always allowed - else - return Is_Descendent_Of (T1, Base_Type (RTE (RE_Address))); - end if; - end Is_Descendent_Of_Address; + elsif Is_Variable (AV) then + return True; - -------------- - -- Is_False -- - -------------- + -- Unchecked conversions are allowed only if they come from the + -- generated code, which sometimes uses unchecked conversions for out + -- parameters in cases where code generation is unaffected. We tell + -- source unchecked conversions by seeing if they are rewrites of an + -- original Unchecked_Conversion function call, or of an explicit + -- conversion of a function call. - function Is_False (U : Uint) return Boolean is - begin - return (U = 0); - end Is_False; + elsif Nkind (AV) = N_Unchecked_Type_Conversion then + if Nkind (Original_Node (AV)) = N_Function_Call then + return False; - --------------------------- - -- Is_Fixed_Model_Number -- - --------------------------- + elsif Comes_From_Source (AV) + and then Nkind (Original_Node (Expression (AV))) = N_Function_Call + then + return False; - function Is_Fixed_Model_Number (U : Ureal; T : Entity_Id) return Boolean is - S : constant Ureal := Small_Value (T); - M : Urealp.Save_Mark; - R : Boolean; + elsif Nkind (Original_Node (AV)) = N_Type_Conversion then + return Is_OK_Variable_For_Out_Formal (Expression (AV)); - begin - M := Urealp.Mark; - R := (U = UR_Trunc (U / S) * S); - Urealp.Release (M); - return R; - end Is_Fixed_Model_Number; + else + return True; + end if; - ------------------------------- - -- Is_Fully_Initialized_Type -- - ------------------------------- + -- Normal type conversions are allowed if argument is a variable - function Is_Fully_Initialized_Type (Typ : Entity_Id) return Boolean is - begin - if Is_Scalar_Type (Typ) then - return False; + elsif Nkind (AV) = N_Type_Conversion then + if Is_Variable (Expression (AV)) + and then Paren_Count (Expression (AV)) = 0 + then + Note_Possible_Modification (Expression (AV), Sure => True); + return True; - elsif Is_Access_Type (Typ) then - return True; + -- We also allow a non-parenthesized expression that raises + -- constraint error if it rewrites what used to be a variable - elsif Is_Array_Type (Typ) then - if Is_Fully_Initialized_Type (Component_Type (Typ)) then + elsif Raises_Constraint_Error (Expression (AV)) + and then Paren_Count (Expression (AV)) = 0 + and then Is_Variable (Original_Node (Expression (AV))) + then return True; + + -- Type conversion of something other than a variable + + else + return False; end if; - -- An interesting case, if we have a constrained type one of whose - -- bounds is known to be null, then there are no elements to be - -- initialized, so all the elements are initialized! + -- If this node is rewritten, then test the original form, if that is + -- OK, then we consider the rewritten node OK (for example, if the + -- original node is a conversion, then Is_Variable will not be true + -- but we still want to allow the conversion if it converts a variable). - if Is_Constrained (Typ) then - declare - Indx : Node_Id; - Indx_Typ : Entity_Id; - Lbd, Hbd : Node_Id; + elsif Original_Node (AV) /= AV then + return Is_OK_Variable_For_Out_Formal (Original_Node (AV)); - begin - Indx := First_Index (Typ); - while Present (Indx) loop + -- All other non-variables are rejected - if Etype (Indx) = Any_Type then - return False; + else + return False; + end if; + end Is_OK_Variable_For_Out_Formal; - -- If index is a range, use directly + ----------------------------------- + -- Is_Partially_Initialized_Type -- + ----------------------------------- - elsif Nkind (Indx) = N_Range then - Lbd := Low_Bound (Indx); - Hbd := High_Bound (Indx); + function Is_Partially_Initialized_Type (Typ : Entity_Id) return Boolean is + begin + if Is_Scalar_Type (Typ) then + return False; - else - Indx_Typ := Etype (Indx); + elsif Is_Access_Type (Typ) then + return True; - if Is_Private_Type (Indx_Typ) then - Indx_Typ := Full_View (Indx_Typ); - end if; + elsif Is_Array_Type (Typ) then - if No (Indx_Typ) then - return False; - else - Lbd := Type_Low_Bound (Indx_Typ); - Hbd := Type_High_Bound (Indx_Typ); - end if; - end if; + -- If component type is partially initialized, so is array type - if Compile_Time_Known_Value (Lbd) - and then Compile_Time_Known_Value (Hbd) - then - if Expr_Value (Hbd) < Expr_Value (Lbd) then - return True; - end if; - end if; + if Is_Partially_Initialized_Type (Component_Type (Typ)) then + return True; - Next_Index (Indx); - end loop; - end; + -- Otherwise we are only partially initialized if we are fully + -- initialized (this is the empty array case, no point in us + -- duplicating that code here). + + else + return Is_Fully_Initialized_Type (Typ); end if; - -- If no null indexes, then type is not fully initialized + elsif Is_Record_Type (Typ) then - return False; + -- A discriminated type is always partially initialized - -- Record types + if Has_Discriminants (Typ) then + return True; - elsif Is_Record_Type (Typ) then - if Has_Discriminants (Typ) - and then - Present (Discriminant_Default_Value (First_Discriminant (Typ))) - and then Is_Fully_Initialized_Variant (Typ) - then + -- A tagged type is always partially initialized + + elsif Is_Tagged_Type (Typ) then return True; - end if; - -- Controlled records are considered to be fully initialized if - -- there is a user defined Initialize routine. This may not be - -- entirely correct, but as the spec notes, we are guessing here - -- what is best from the point of view of issuing warnings. + -- Case of non-discriminated record - if Is_Controlled (Typ) then + else declare - Utyp : constant Entity_Id := Underlying_Type (Typ); + Ent : Entity_Id; + + Component_Present : Boolean := False; + -- Set True if at least one component is present. If no + -- components are present, then record type is fully + -- initialized (another odd case, like the null array). begin - if Present (Utyp) then - declare - Init : constant Entity_Id := - (Find_Prim_Op - (Underlying_Type (Typ), Name_Initialize)); + -- Loop through components - begin - if Present (Init) - and then Comes_From_Source (Init) - and then not - Is_Predefined_File_Name - (File_Name (Get_Source_File_Index (Sloc (Init)))) - then - return True; + Ent := First_Entity (Typ); + while Present (Ent) loop + if Ekind (Ent) = E_Component then + Component_Present := True; - elsif Has_Null_Extension (Typ) - and then - Is_Fully_Initialized_Type - (Etype (Base_Type (Typ))) + -- If a component has an initialization expression then + -- the enclosing record type is partially initialized + + if Present (Parent (Ent)) + and then Present (Expression (Parent (Ent))) then return True; - end if; - end; - end if; - end; - end if; - -- Otherwise see if all record components are initialized + -- If a component is of a type which is itself partially + -- initialized, then the enclosing record type is also. - declare - Ent : Entity_Id; + elsif Is_Partially_Initialized_Type (Etype (Ent)) then + return True; + end if; + end if; - begin - Ent := First_Entity (Typ); + Next_Entity (Ent); + end loop; - while Present (Ent) loop - if Chars (Ent) = Name_uController then - null; + -- No initialized components found. If we found any components + -- they were all uninitialized so the result is false. - elsif Ekind (Ent) = E_Component - and then (No (Parent (Ent)) - or else No (Expression (Parent (Ent)))) - and then not Is_Fully_Initialized_Type (Etype (Ent)) - then + if Component_Present then return False; - end if; - Next_Entity (Ent); - end loop; - end; + -- But if we found no components, then all the components are + -- initialized so we consider the type to be initialized. - -- No uninitialized components, so type is fully initialized. - -- Note that this catches the case of no components as well. + else + return True; + end if; + end; + end if; - return True; + -- Concurrent types are always fully initialized elsif Is_Concurrent_Type (Typ) then return True; + -- For a private type, go to underlying type. If there is no underlying + -- type then just assume this partially initialized. Not clear if this + -- can happen in a non-error case, but no harm in testing for this. + elsif Is_Private_Type (Typ) then declare U : constant Entity_Id := Underlying_Type (Typ); - begin if No (U) then - return False; + return True; else - return Is_Fully_Initialized_Type (U); + return Is_Partially_Initialized_Type (U); end if; end; + -- For any other type (are there any?) assume partially initialized + else - return False; + return True; end if; - end Is_Fully_Initialized_Type; + end Is_Partially_Initialized_Type; - ---------------------------------- - -- Is_Fully_Initialized_Variant -- - ---------------------------------- + ------------------------------------ + -- Is_Potentially_Persistent_Type -- + ------------------------------------ - function Is_Fully_Initialized_Variant (Typ : Entity_Id) return Boolean is - Loc : constant Source_Ptr := Sloc (Typ); - Constraints : constant List_Id := New_List; - Components : constant Elist_Id := New_Elmt_List; - Comp_Elmt : Elmt_Id; - Comp_Id : Node_Id; - Comp_List : Node_Id; - Discr : Entity_Id; - Discr_Val : Node_Id; - Report_Errors : Boolean; + function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean is + Comp : Entity_Id; + Indx : Node_Id; begin - if Serious_Errors_Detected > 0 then - return False; - end if; - - if Is_Record_Type (Typ) - and then Nkind (Parent (Typ)) = N_Full_Type_Declaration - and then Nkind (Type_Definition (Parent (Typ))) = N_Record_Definition - then - Comp_List := Component_List (Type_Definition (Parent (Typ))); - Discr := First_Discriminant (Typ); - - while Present (Discr) loop - if Nkind (Parent (Discr)) = N_Discriminant_Specification then - Discr_Val := Expression (Parent (Discr)); - - if Present (Discr_Val) - and then Is_OK_Static_Expression (Discr_Val) - then - Append_To (Constraints, - Make_Component_Association (Loc, - Choices => New_List (New_Occurrence_Of (Discr, Loc)), - Expression => New_Copy (Discr_Val))); - else - return False; - end if; - else - return False; - end if; - - Next_Discriminant (Discr); - end loop; + -- For private type, test corresponding full type - Gather_Components - (Typ => Typ, - Comp_List => Comp_List, - Governed_By => Constraints, - Into => Components, - Report_Errors => Report_Errors); + if Is_Private_Type (T) then + return Is_Potentially_Persistent_Type (Full_View (T)); - -- Check that each component present is fully initialized + -- Scalar types are potentially persistent - Comp_Elmt := First_Elmt (Components); + elsif Is_Scalar_Type (T) then + return True; - while Present (Comp_Elmt) loop - Comp_Id := Node (Comp_Elmt); + -- Record type is potentially persistent if not tagged and the types of + -- all it components are potentially persistent, and no component has + -- an initialization expression. - if Ekind (Comp_Id) = E_Component - and then (No (Parent (Comp_Id)) - or else No (Expression (Parent (Comp_Id)))) - and then not Is_Fully_Initialized_Type (Etype (Comp_Id)) - then + elsif Is_Record_Type (T) + and then not Is_Tagged_Type (T) + and then not Is_Partially_Initialized_Type (T) + then + Comp := First_Component (T); + while Present (Comp) loop + if not Is_Potentially_Persistent_Type (Etype (Comp)) then return False; + else + Next_Entity (Comp); end if; - - Next_Elmt (Comp_Elmt); end loop; return True; - elsif Is_Private_Type (Typ) then - declare - U : constant Entity_Id := Underlying_Type (Typ); + -- Array type is potentially persistent if its component type is + -- potentially persistent and if all its constraints are static. - begin - if No (U) then + elsif Is_Array_Type (T) then + if not Is_Potentially_Persistent_Type (Component_Type (T)) then + return False; + end if; + + Indx := First_Index (T); + while Present (Indx) loop + if not Is_OK_Static_Subtype (Etype (Indx)) then return False; else - return Is_Fully_Initialized_Variant (U); + Next_Index (Indx); end if; - end; - else - return False; - end if; - end Is_Fully_Initialized_Variant; - - ---------------------------- - -- Is_Inherited_Operation -- - ---------------------------- - - function Is_Inherited_Operation (E : Entity_Id) return Boolean is - Kind : constant Node_Kind := Nkind (Parent (E)); - begin - pragma Assert (Is_Overloadable (E)); - return Kind = N_Full_Type_Declaration - or else Kind = N_Private_Extension_Declaration - or else Kind = N_Subtype_Declaration - or else (Ekind (E) = E_Enumeration_Literal - and then Is_Derived_Type (Etype (E))); - end Is_Inherited_Operation; + end loop; - ----------------------------- - -- Is_Library_Level_Entity -- - ----------------------------- + return True; - function Is_Library_Level_Entity (E : Entity_Id) return Boolean is - begin - -- The following is a small optimization, and it also handles - -- properly discriminals, which in task bodies might appear in - -- expressions before the corresponding procedure has been - -- created, and which therefore do not have an assigned scope. + -- All other types are not potentially persistent - if Ekind (E) in Formal_Kind then + else return False; end if; - - -- Normal test is simply that the enclosing dynamic scope is Standard - - return Enclosing_Dynamic_Scope (E) = Standard_Standard; - end Is_Library_Level_Entity; + end Is_Potentially_Persistent_Type; --------------------------------- - -- Is_Local_Variable_Reference -- + -- Is_Protected_Self_Reference -- --------------------------------- - function Is_Local_Variable_Reference (Expr : Node_Id) return Boolean is - begin - if not Is_Entity_Name (Expr) then - return False; - - else - declare - Ent : constant Entity_Id := Entity (Expr); - Sub : constant Entity_Id := Enclosing_Subprogram (Ent); + function Is_Protected_Self_Reference (N : Node_Id) return Boolean + is + function In_Access_Definition (N : Node_Id) return Boolean; + -- Returns true if N belongs to an access definition - begin - if Ekind (Ent) /= E_Variable - and then - Ekind (Ent) /= E_In_Out_Parameter - then - return False; + -------------------------- + -- In_Access_Definition -- + -------------------------- - else - return Present (Sub) and then Sub = Current_Subprogram; + function In_Access_Definition (N : Node_Id) return Boolean + is + P : Node_Id := Parent (N); + begin + while Present (P) loop + if Nkind (P) = N_Access_Definition then + return True; end if; - end; - end if; - end Is_Local_Variable_Reference; - - --------------- - -- Is_Lvalue -- - --------------- + P := Parent (P); + end loop; + return False; + end In_Access_Definition; - function Is_Lvalue (N : Node_Id) return Boolean is - P : constant Node_Id := Parent (N); + -- Start of processing for Is_Protected_Self_Reference begin - case Nkind (P) is + return Ada_Version >= Ada_05 + and then Is_Entity_Name (N) + and then Is_Protected_Type (Entity (N)) + and then In_Open_Scopes (Entity (N)) + and then not In_Access_Definition (N); + end Is_Protected_Self_Reference; - -- Test left side of assignment + ----------------------------- + -- Is_RCI_Pkg_Spec_Or_Body -- + ----------------------------- - when N_Assignment_Statement => - return N = Name (P); + function Is_RCI_Pkg_Spec_Or_Body (Cunit : Node_Id) return Boolean is - -- Test prefix of component or attribute + function Is_RCI_Pkg_Decl_Cunit (Cunit : Node_Id) return Boolean; + -- Return True if the unit of Cunit is an RCI package declaration - when N_Attribute_Reference | - N_Expanded_Name | - N_Explicit_Dereference | - N_Indexed_Component | - N_Reference | - N_Selected_Component | - N_Slice => - return N = Prefix (P); + --------------------------- + -- Is_RCI_Pkg_Decl_Cunit -- + --------------------------- - -- Test subprogram parameter (we really should check the - -- parameter mode, but it is not worth the trouble) + function Is_RCI_Pkg_Decl_Cunit (Cunit : Node_Id) return Boolean is + The_Unit : constant Node_Id := Unit (Cunit); - when N_Function_Call | - N_Procedure_Call_Statement | - N_Accept_Statement | - N_Parameter_Association => - return True; + begin + if Nkind (The_Unit) /= N_Package_Declaration then + return False; + end if; - -- Test for appearing in a conversion that itself appears - -- in an lvalue context, since this should be an lvalue. + return Is_Remote_Call_Interface (Defining_Entity (The_Unit)); + end Is_RCI_Pkg_Decl_Cunit; - when N_Type_Conversion => - return Is_Lvalue (P); + -- Start of processing for Is_RCI_Pkg_Spec_Or_Body - -- Test for appearence in object renaming declaration + begin + return Is_RCI_Pkg_Decl_Cunit (Cunit) + or else + (Nkind (Unit (Cunit)) = N_Package_Body + and then Is_RCI_Pkg_Decl_Cunit (Library_Unit (Cunit))); + end Is_RCI_Pkg_Spec_Or_Body; - when N_Object_Renaming_Declaration => - return True; + ----------------------------------------- + -- Is_Remote_Access_To_Class_Wide_Type -- + ----------------------------------------- - -- All other references are definitely not Lvalues + function Is_Remote_Access_To_Class_Wide_Type + (E : Entity_Id) return Boolean + is + begin + -- A remote access to class-wide type is a general access to object type + -- declared in the visible part of a Remote_Types or Remote_Call_ + -- Interface unit. - when others => - return False; + return Ekind (E) = E_General_Access_Type + and then (Is_Remote_Call_Interface (E) or else Is_Remote_Types (E)); + end Is_Remote_Access_To_Class_Wide_Type; - end case; - end Is_Lvalue; + ----------------------------------------- + -- Is_Remote_Access_To_Subprogram_Type -- + ----------------------------------------- - ------------------------- - -- Is_Object_Reference -- - ------------------------- + function Is_Remote_Access_To_Subprogram_Type + (E : Entity_Id) return Boolean + is + begin + return (Ekind (E) = E_Access_Subprogram_Type + or else (Ekind (E) = E_Record_Type + and then Present (Corresponding_Remote_Type (E)))) + and then (Is_Remote_Call_Interface (E) or else Is_Remote_Types (E)); + end Is_Remote_Access_To_Subprogram_Type; - function Is_Object_Reference (N : Node_Id) return Boolean is + -------------------- + -- Is_Remote_Call -- + -------------------- + + function Is_Remote_Call (N : Node_Id) return Boolean is begin - if Is_Entity_Name (N) then - return Is_Object (Entity (N)); + if Nkind (N) /= N_Procedure_Call_Statement + and then Nkind (N) /= N_Function_Call + then + -- An entry call cannot be remote - else - case Nkind (N) is - when N_Indexed_Component | N_Slice => - return Is_Object_Reference (Prefix (N)); + return False; - -- In Ada95, a function call is a constant object + elsif Nkind (Name (N)) in N_Has_Entity + and then Is_Remote_Call_Interface (Entity (Name (N))) + then + -- A subprogram declared in the spec of a RCI package is remote - when N_Function_Call => - return True; + return True; - -- A reference to the stream attribute Input is a function call + elsif Nkind (Name (N)) = N_Explicit_Dereference + and then Is_Remote_Access_To_Subprogram_Type + (Etype (Prefix (Name (N)))) + then + -- The dereference of a RAS is a remote call - when N_Attribute_Reference => - return Attribute_Name (N) = Name_Input; + return True; - when N_Selected_Component => - return - Is_Object_Reference (Selector_Name (N)) - and then Is_Object_Reference (Prefix (N)); + elsif Present (Controlling_Argument (N)) + and then Is_Remote_Access_To_Class_Wide_Type + (Etype (Controlling_Argument (N))) + then + -- Any primitive operation call with a controlling argument of + -- a RACW type is a remote call. - when N_Explicit_Dereference => - return True; + return True; + end if; - -- A view conversion of a tagged object is an object reference + -- All other calls are local calls - when N_Type_Conversion => - return Is_Tagged_Type (Etype (Subtype_Mark (N))) - and then Is_Tagged_Type (Etype (Expression (N))) - and then Is_Object_Reference (Expression (N)); + return False; + end Is_Remote_Call; - -- An unchecked type conversion is considered to be an object if - -- the operand is an object (this construction arises only as a - -- result of expansion activities). + ---------------------- + -- Is_Renamed_Entry -- + ---------------------- - when N_Unchecked_Type_Conversion => - return True; + function Is_Renamed_Entry (Proc_Nam : Entity_Id) return Boolean is + Orig_Node : Node_Id := Empty; + Subp_Decl : Node_Id := Parent (Parent (Proc_Nam)); - when others => - return False; - end case; - end if; - end Is_Object_Reference; + function Is_Entry (Nam : Node_Id) return Boolean; + -- Determine whether Nam is an entry. Traverse selectors if there are + -- nested selected components. - ----------------------------------- - -- Is_OK_Variable_For_Out_Formal -- - ----------------------------------- + -------------- + -- Is_Entry -- + -------------- + + function Is_Entry (Nam : Node_Id) return Boolean is + begin + if Nkind (Nam) = N_Selected_Component then + return Is_Entry (Selector_Name (Nam)); + end if; + + return Ekind (Entity (Nam)) = E_Entry; + end Is_Entry; + + -- Start of processing for Is_Renamed_Entry - function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean is begin - Note_Possible_Modification (AV); + if Present (Alias (Proc_Nam)) then + Subp_Decl := Parent (Parent (Alias (Proc_Nam))); + end if; - -- We must reject parenthesized variable names. The check for - -- Comes_From_Source is present because there are currently - -- cases where the compiler violates this rule (e.g. passing - -- a task object to its controlled Initialize routine). + -- Look for a rewritten subprogram renaming declaration - if Paren_Count (AV) > 0 and then Comes_From_Source (AV) then - return False; + if Nkind (Subp_Decl) = N_Subprogram_Declaration + and then Present (Original_Node (Subp_Decl)) + then + Orig_Node := Original_Node (Subp_Decl); + end if; - -- A variable is always allowed + -- The rewritten subprogram is actually an entry - elsif Is_Variable (AV) then + if Present (Orig_Node) + and then Nkind (Orig_Node) = N_Subprogram_Renaming_Declaration + and then Is_Entry (Name (Orig_Node)) + then return True; + end if; - -- Unchecked conversions are allowed only if they come from the - -- generated code, which sometimes uses unchecked conversions for - -- out parameters in cases where code generation is unaffected. - -- We tell source unchecked conversions by seeing if they are - -- rewrites of an original UC function call, or of an explicit - -- conversion of a function call. + return False; + end Is_Renamed_Entry; - elsif Nkind (AV) = N_Unchecked_Type_Conversion then - if Nkind (Original_Node (AV)) = N_Function_Call then - return False; + ---------------------- + -- Is_Selector_Name -- + ---------------------- - elsif Comes_From_Source (AV) - and then Nkind (Original_Node (Expression (AV))) = N_Function_Call - then - return False; + function Is_Selector_Name (N : Node_Id) return Boolean is + begin + if not Is_List_Member (N) then + declare + P : constant Node_Id := Parent (N); + K : constant Node_Kind := Nkind (P); + begin + return + (K = N_Expanded_Name or else + K = N_Generic_Association or else + K = N_Parameter_Association or else + K = N_Selected_Component) + and then Selector_Name (P) = N; + end; - elsif Nkind (Original_Node (AV)) = N_Type_Conversion then - return Is_OK_Variable_For_Out_Formal (Expression (AV)); + else + declare + L : constant List_Id := List_Containing (N); + P : constant Node_Id := Parent (L); + begin + return (Nkind (P) = N_Discriminant_Association + and then Selector_Names (P) = L) + or else + (Nkind (P) = N_Component_Association + and then Choices (P) = L); + end; + end if; + end Is_Selector_Name; - else - return True; - end if; + ------------------ + -- Is_Statement -- + ------------------ - -- Normal type conversions are allowed if argument is a variable + function Is_Statement (N : Node_Id) return Boolean is + begin + return + Nkind (N) in N_Statement_Other_Than_Procedure_Call + or else Nkind (N) = N_Procedure_Call_Statement; + end Is_Statement; - elsif Nkind (AV) = N_Type_Conversion then - if Is_Variable (Expression (AV)) - and then Paren_Count (Expression (AV)) = 0 - then - Note_Possible_Modification (Expression (AV)); - return True; + --------------------------------- + -- Is_Synchronized_Tagged_Type -- + --------------------------------- - -- We also allow a non-parenthesized expression that raises - -- constraint error if it rewrites what used to be a variable + function Is_Synchronized_Tagged_Type (E : Entity_Id) return Boolean is + Kind : constant Entity_Kind := Ekind (Base_Type (E)); - elsif Raises_Constraint_Error (Expression (AV)) - and then Paren_Count (Expression (AV)) = 0 - and then Is_Variable (Original_Node (Expression (AV))) - then - return True; + begin + -- A task or protected type derived from an interface is a tagged type. + -- Such a tagged type is called a synchronized tagged type, as are + -- synchronized interfaces and private extensions whose declaration + -- includes the reserved word synchronized. - -- Type conversion of something other than a variable + return (Is_Tagged_Type (E) + and then (Kind = E_Task_Type + or else Kind = E_Protected_Type)) + or else + (Is_Interface (E) + and then Is_Synchronized_Interface (E)) + or else + (Ekind (E) = E_Record_Type_With_Private + and then (Synchronized_Present (Parent (E)) + or else Is_Synchronized_Interface (Etype (E)))); + end Is_Synchronized_Tagged_Type; - else - return False; - end if; + ----------------- + -- Is_Transfer -- + ----------------- - -- If this node is rewritten, then test the original form, if that is - -- OK, then we consider the rewritten node OK (for example, if the - -- original node is a conversion, then Is_Variable will not be true - -- but we still want to allow the conversion if it converts a variable). + function Is_Transfer (N : Node_Id) return Boolean is + Kind : constant Node_Kind := Nkind (N); - elsif Original_Node (AV) /= AV then - return Is_OK_Variable_For_Out_Formal (Original_Node (AV)); + begin + if Kind = N_Simple_Return_Statement + or else + Kind = N_Extended_Return_Statement + or else + Kind = N_Goto_Statement + or else + Kind = N_Raise_Statement + or else + Kind = N_Requeue_Statement + then + return True; + + elsif (Kind = N_Exit_Statement or else Kind in N_Raise_xxx_Error) + and then No (Condition (N)) + then + return True; - -- All other non-variables are rejected + elsif Kind = N_Procedure_Call_Statement + and then Is_Entity_Name (Name (N)) + and then Present (Entity (Name (N))) + and then No_Return (Entity (Name (N))) + then + return True; + + elsif Nkind (Original_Node (N)) = N_Raise_Statement then + return True; else return False; end if; - end Is_OK_Variable_For_Out_Formal; + end Is_Transfer; - ----------------------------------- - -- Is_Partially_Initialized_Type -- - ----------------------------------- + ------------- + -- Is_True -- + ------------- - function Is_Partially_Initialized_Type (Typ : Entity_Id) return Boolean is + function Is_True (U : Uint) return Boolean is begin - if Is_Scalar_Type (Typ) then - return False; - - elsif Is_Access_Type (Typ) then - return True; - - elsif Is_Array_Type (Typ) then - - -- If component type is partially initialized, so is array type + return (U /= 0); + end Is_True; - if Is_Partially_Initialized_Type (Component_Type (Typ)) then - return True; + ------------------- + -- Is_Value_Type -- + ------------------- - -- Otherwise we are only partially initialized if we are fully - -- initialized (this is the empty array case, no point in us - -- duplicating that code here). + function Is_Value_Type (T : Entity_Id) return Boolean is + begin + return VM_Target = CLI_Target + and then Chars (T) /= No_Name + and then Get_Name_String (Chars (T)) = "valuetype"; + end Is_Value_Type; - else - return Is_Fully_Initialized_Type (Typ); - end if; + ----------------- + -- Is_Variable -- + ----------------- - elsif Is_Record_Type (Typ) then + function Is_Variable (N : Node_Id) return Boolean is - -- A discriminated type is always partially initialized + Orig_Node : constant Node_Id := Original_Node (N); + -- We do the test on the original node, since this is basically a + -- test of syntactic categories, so it must not be disturbed by + -- whatever rewriting might have occurred. For example, an aggregate, + -- which is certainly NOT a variable, could be turned into a variable + -- by expansion. - if Has_Discriminants (Typ) then - return True; + function In_Protected_Function (E : Entity_Id) return Boolean; + -- Within a protected function, the private components of the + -- enclosing protected type are constants. A function nested within + -- a (protected) procedure is not itself protected. - -- A tagged type is always partially initialized + function Is_Variable_Prefix (P : Node_Id) return Boolean; + -- Prefixes can involve implicit dereferences, in which case we + -- must test for the case of a reference of a constant access + -- type, which can never be a variable. - elsif Is_Tagged_Type (Typ) then - return True; + --------------------------- + -- In_Protected_Function -- + --------------------------- - -- Case of non-discriminated record + function In_Protected_Function (E : Entity_Id) return Boolean is + Prot : constant Entity_Id := Scope (E); + S : Entity_Id; + begin + if not Is_Protected_Type (Prot) then + return False; else - declare - Ent : Entity_Id; + S := Current_Scope; + while Present (S) and then S /= Prot loop + if Ekind (S) = E_Function + and then Scope (S) = Prot + then + return True; + end if; - Component_Present : Boolean := False; - -- Set True if at least one component is present. If no - -- components are present, then record type is fully - -- initialized (another odd case, like the null array). + S := Scope (S); + end loop; - begin - -- Loop through components + return False; + end if; + end In_Protected_Function; - Ent := First_Entity (Typ); - while Present (Ent) loop - if Ekind (Ent) = E_Component then - Component_Present := True; + ------------------------ + -- Is_Variable_Prefix -- + ------------------------ - -- If a component has an initialization expression then - -- the enclosing record type is partially initialized + function Is_Variable_Prefix (P : Node_Id) return Boolean is + begin + if Is_Access_Type (Etype (P)) then + return not Is_Access_Constant (Root_Type (Etype (P))); - if Present (Parent (Ent)) - and then Present (Expression (Parent (Ent))) - then - return True; + -- For the case of an indexed component whose prefix has a packed + -- array type, the prefix has been rewritten into a type conversion. + -- Determine variable-ness from the converted expression. - -- If a component is of a type which is itself partially - -- initialized, then the enclosing record type is also. + elsif Nkind (P) = N_Type_Conversion + and then not Comes_From_Source (P) + and then Is_Array_Type (Etype (P)) + and then Is_Packed (Etype (P)) + then + return Is_Variable (Expression (P)); - elsif Is_Partially_Initialized_Type (Etype (Ent)) then - return True; - end if; - end if; + else + return Is_Variable (P); + end if; + end Is_Variable_Prefix; - Next_Entity (Ent); - end loop; + -- Start of processing for Is_Variable - -- No initialized components found. If we found any components - -- they were all uninitialized so the result is false. + begin + -- Definitely OK if Assignment_OK is set. Since this is something that + -- only gets set for expanded nodes, the test is on N, not Orig_Node. - if Component_Present then - return False; + if Nkind (N) in N_Subexpr and then Assignment_OK (N) then + return True; - -- But if we found no components, then all the components are - -- initialized so we consider the type to be initialized. + -- Normally we go to the original node, but there is one exception + -- where we use the rewritten node, namely when it is an explicit + -- dereference. The generated code may rewrite a prefix which is an + -- access type with an explicit dereference. The dereference is a + -- variable, even though the original node may not be (since it could + -- be a constant of the access type). - else - return True; - end if; - end; - end if; + -- In Ada 2005 we have a further case to consider: the prefix may be + -- a function call given in prefix notation. The original node appears + -- to be a selected component, but we need to examine the call. - -- Concurrent types are always fully initialized + elsif Nkind (N) = N_Explicit_Dereference + and then Nkind (Orig_Node) /= N_Explicit_Dereference + and then Present (Etype (Orig_Node)) + and then Is_Access_Type (Etype (Orig_Node)) + then + return Is_Variable_Prefix (Original_Node (Prefix (N))) + or else + (Nkind (Orig_Node) = N_Function_Call + and then not Is_Access_Constant (Etype (Prefix (N)))); - elsif Is_Concurrent_Type (Typ) then - return True; + -- A function call is never a variable - -- For a private type, go to underlying type. If there is no underlying - -- type then just assume this partially initialized. Not clear if this - -- can happen in a non-error case, but no harm in testing for this. + elsif Nkind (N) = N_Function_Call then + return False; - elsif Is_Private_Type (Typ) then + -- All remaining checks use the original node + + elsif Is_Entity_Name (Orig_Node) + and then Present (Entity (Orig_Node)) + then declare - U : constant Entity_Id := Underlying_Type (Typ); + E : constant Entity_Id := Entity (Orig_Node); + K : constant Entity_Kind := Ekind (E); begin - if No (U) then - return True; - else - return Is_Partially_Initialized_Type (U); - end if; - end; - - -- For any other type (are there any?) assume partially initialized - - else - return True; - end if; - end Is_Partially_Initialized_Type; - - ------------------------------------ - -- Is_Potentially_Persistent_Type -- - ------------------------------------ + return (K = E_Variable + and then Nkind (Parent (E)) /= N_Exception_Handler) + or else (K = E_Component + and then not In_Protected_Function (E)) + or else K = E_Out_Parameter + or else K = E_In_Out_Parameter + or else K = E_Generic_In_Out_Parameter - function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean is - Comp : Entity_Id; - Indx : Node_Id; + -- Current instance of type: - begin - -- For private type, test corrresponding full type + or else (Is_Type (E) and then In_Open_Scopes (E)) + or else (Is_Incomplete_Or_Private_Type (E) + and then In_Open_Scopes (Full_View (E))); + end; - if Is_Private_Type (T) then - return Is_Potentially_Persistent_Type (Full_View (T)); + else + case Nkind (Orig_Node) is + when N_Indexed_Component | N_Slice => + return Is_Variable_Prefix (Prefix (Orig_Node)); - -- Scalar types are potentially persistent + when N_Selected_Component => + return Is_Variable_Prefix (Prefix (Orig_Node)) + and then Is_Variable (Selector_Name (Orig_Node)); - elsif Is_Scalar_Type (T) then - return True; + -- For an explicit dereference, the type of the prefix cannot + -- be an access to constant or an access to subprogram. - -- Record type is potentially persistent if not tagged and the types of - -- all it components are potentially persistent, and no component has - -- an initialization expression. + when N_Explicit_Dereference => + declare + Typ : constant Entity_Id := Etype (Prefix (Orig_Node)); + begin + return Is_Access_Type (Typ) + and then not Is_Access_Constant (Root_Type (Typ)) + and then Ekind (Typ) /= E_Access_Subprogram_Type; + end; - elsif Is_Record_Type (T) - and then not Is_Tagged_Type (T) - and then not Is_Partially_Initialized_Type (T) - then - Comp := First_Component (T); - while Present (Comp) loop - if not Is_Potentially_Persistent_Type (Etype (Comp)) then - return False; - else - Next_Entity (Comp); - end if; - end loop; + -- The type conversion is the case where we do not deal with the + -- context dependent special case of an actual parameter. Thus + -- the type conversion is only considered a variable for the + -- purposes of this routine if the target type is tagged. However, + -- a type conversion is considered to be a variable if it does not + -- come from source (this deals for example with the conversions + -- of expressions to their actual subtypes). - return True; + when N_Type_Conversion => + return Is_Variable (Expression (Orig_Node)) + and then + (not Comes_From_Source (Orig_Node) + or else + (Is_Tagged_Type (Etype (Subtype_Mark (Orig_Node))) + and then + Is_Tagged_Type (Etype (Expression (Orig_Node))))); - -- Array type is potentially persistent if its component type is - -- potentially persistent and if all its constraints are static. + -- GNAT allows an unchecked type conversion as a variable. This + -- only affects the generation of internal expanded code, since + -- calls to instantiations of Unchecked_Conversion are never + -- considered variables (since they are function calls). + -- This is also true for expression actions. - elsif Is_Array_Type (T) then - if not Is_Potentially_Persistent_Type (Component_Type (T)) then - return False; - end if; + when N_Unchecked_Type_Conversion => + return Is_Variable (Expression (Orig_Node)); - Indx := First_Index (T); - while Present (Indx) loop - if not Is_OK_Static_Subtype (Etype (Indx)) then + when others => return False; - else - Next_Index (Indx); - end if; - end loop; - - return True; - - -- All other types are not potentially persistent - - else - return False; + end case; end if; - end Is_Potentially_Persistent_Type; - - ----------------------------- - -- Is_RCI_Pkg_Spec_Or_Body -- - ----------------------------- - - function Is_RCI_Pkg_Spec_Or_Body (Cunit : Node_Id) return Boolean is + end Is_Variable; - function Is_RCI_Pkg_Decl_Cunit (Cunit : Node_Id) return Boolean; - -- Return True if the unit of Cunit is an RCI package declaration + ------------------------ + -- Is_Volatile_Object -- + ------------------------ - --------------------------- - -- Is_RCI_Pkg_Decl_Cunit -- - --------------------------- + function Is_Volatile_Object (N : Node_Id) return Boolean is - function Is_RCI_Pkg_Decl_Cunit (Cunit : Node_Id) return Boolean is - The_Unit : constant Node_Id := Unit (Cunit); + function Object_Has_Volatile_Components (N : Node_Id) return Boolean; + -- Determines if given object has volatile components - begin - if Nkind (The_Unit) /= N_Package_Declaration then - return False; - end if; - return Is_Remote_Call_Interface (Defining_Entity (The_Unit)); - end Is_RCI_Pkg_Decl_Cunit; + function Is_Volatile_Prefix (N : Node_Id) return Boolean; + -- If prefix is an implicit dereference, examine designated type - -- Start of processing for Is_RCI_Pkg_Spec_Or_Body + ------------------------ + -- Is_Volatile_Prefix -- + ------------------------ - begin - return Is_RCI_Pkg_Decl_Cunit (Cunit) - or else - (Nkind (Unit (Cunit)) = N_Package_Body - and then Is_RCI_Pkg_Decl_Cunit (Library_Unit (Cunit))); - end Is_RCI_Pkg_Spec_Or_Body; + function Is_Volatile_Prefix (N : Node_Id) return Boolean is + Typ : constant Entity_Id := Etype (N); - ----------------------------------------- - -- Is_Remote_Access_To_Class_Wide_Type -- - ----------------------------------------- + begin + if Is_Access_Type (Typ) then + declare + Dtyp : constant Entity_Id := Designated_Type (Typ); - function Is_Remote_Access_To_Class_Wide_Type - (E : Entity_Id) return Boolean - is - D : Entity_Id; + begin + return Is_Volatile (Dtyp) + or else Has_Volatile_Components (Dtyp); + end; - function Comes_From_Limited_Private_Type_Declaration - (E : Entity_Id) return Boolean; - -- Check that the type is declared by a limited type declaration, - -- or else is derived from a Remote_Type ancestor through private - -- extensions. + else + return Object_Has_Volatile_Components (N); + end if; + end Is_Volatile_Prefix; - ------------------------------------------------- - -- Comes_From_Limited_Private_Type_Declaration -- - ------------------------------------------------- + ------------------------------------ + -- Object_Has_Volatile_Components -- + ------------------------------------ - function Comes_From_Limited_Private_Type_Declaration - (E : Entity_Id) return Boolean - is - N : constant Node_Id := Declaration_Node (E); + function Object_Has_Volatile_Components (N : Node_Id) return Boolean is + Typ : constant Entity_Id := Etype (N); begin - if Nkind (N) = N_Private_Type_Declaration - and then Limited_Present (N) + if Is_Volatile (Typ) + or else Has_Volatile_Components (Typ) then return True; - end if; - if Nkind (N) = N_Private_Extension_Declaration then - return - Comes_From_Limited_Private_Type_Declaration (Etype (E)) - or else - (Is_Remote_Types (Etype (E)) - and then Is_Limited_Record (Etype (E)) - and then Has_Private_Declaration (Etype (E))); - end if; + elsif Is_Entity_Name (N) + and then (Has_Volatile_Components (Entity (N)) + or else Is_Volatile (Entity (N))) + then + return True; - return False; - end Comes_From_Limited_Private_Type_Declaration; + elsif Nkind (N) = N_Indexed_Component + or else Nkind (N) = N_Selected_Component + then + return Is_Volatile_Prefix (Prefix (N)); + + else + return False; + end if; + end Object_Has_Volatile_Components; - -- Start of processing for Is_Remote_Access_To_Class_Wide_Type + -- Start of processing for Is_Volatile_Object begin - if not (Is_Remote_Call_Interface (E) - or else Is_Remote_Types (E)) - or else Ekind (E) /= E_General_Access_Type + if Is_Volatile (Etype (N)) + or else (Is_Entity_Name (N) and then Is_Volatile (Entity (N))) then - return False; - end if; + return True; - D := Designated_Type (E); + elsif Nkind (N) = N_Indexed_Component + or else Nkind (N) = N_Selected_Component + then + return Is_Volatile_Prefix (Prefix (N)); - if Ekind (D) /= E_Class_Wide_Type then + else return False; end if; + end Is_Volatile_Object; - return Comes_From_Limited_Private_Type_Declaration - (Defining_Identifier (Parent (D))); - end Is_Remote_Access_To_Class_Wide_Type; - - ----------------------------------------- - -- Is_Remote_Access_To_Subprogram_Type -- - ----------------------------------------- + ------------------------- + -- Kill_Current_Values -- + ------------------------- - function Is_Remote_Access_To_Subprogram_Type - (E : Entity_Id) return Boolean + procedure Kill_Current_Values + (Ent : Entity_Id; + Last_Assignment_Only : Boolean := False) is begin - return (Ekind (E) = E_Access_Subprogram_Type - or else (Ekind (E) = E_Record_Type - and then Present (Corresponding_Remote_Type (E)))) - and then (Is_Remote_Call_Interface (E) - or else Is_Remote_Types (E)); - end Is_Remote_Access_To_Subprogram_Type; + if Is_Assignable (Ent) then + Set_Last_Assignment (Ent, Empty); + end if; - -------------------- - -- Is_Remote_Call -- - -------------------- + if not Last_Assignment_Only and then Is_Object (Ent) then + Kill_Checks (Ent); + Set_Current_Value (Ent, Empty); - function Is_Remote_Call (N : Node_Id) return Boolean is - begin - if Nkind (N) /= N_Procedure_Call_Statement - and then Nkind (N) /= N_Function_Call - then - -- An entry call cannot be remote + if not Can_Never_Be_Null (Ent) then + Set_Is_Known_Non_Null (Ent, False); + end if; - return False; + Set_Is_Known_Null (Ent, False); + end if; + end Kill_Current_Values; - elsif Nkind (Name (N)) in N_Has_Entity - and then Is_Remote_Call_Interface (Entity (Name (N))) - then - -- A subprogram declared in the spec of a RCI package is remote + procedure Kill_Current_Values (Last_Assignment_Only : Boolean := False) is + S : Entity_Id; - return True; + procedure Kill_Current_Values_For_Entity_Chain (E : Entity_Id); + -- Clear current value for entity E and all entities chained to E - elsif Nkind (Name (N)) = N_Explicit_Dereference - and then Is_Remote_Access_To_Subprogram_Type - (Etype (Prefix (Name (N)))) - then - -- The dereference of a RAS is a remote call + ------------------------------------------ + -- Kill_Current_Values_For_Entity_Chain -- + ------------------------------------------ - return True; + procedure Kill_Current_Values_For_Entity_Chain (E : Entity_Id) is + Ent : Entity_Id; + begin + Ent := E; + while Present (Ent) loop + Kill_Current_Values (Ent, Last_Assignment_Only); + Next_Entity (Ent); + end loop; + end Kill_Current_Values_For_Entity_Chain; - elsif Present (Controlling_Argument (N)) - and then Is_Remote_Access_To_Class_Wide_Type - (Etype (Controlling_Argument (N))) - then - -- Any primitive operation call with a controlling argument of - -- a RACW type is a remote call. + -- Start of processing for Kill_Current_Values - return True; + begin + -- Kill all saved checks, a special case of killing saved values + + if not Last_Assignment_Only then + Kill_All_Checks; end if; - -- All other calls are local calls + -- Loop through relevant scopes, which includes the current scope and + -- any parent scopes if the current scope is a block or a package. - return False; - end Is_Remote_Call; + S := Current_Scope; + Scope_Loop : loop - ---------------------- - -- Is_Selector_Name -- - ---------------------- + -- Clear current values of all entities in current scope - function Is_Selector_Name (N : Node_Id) return Boolean is - begin - if not Is_List_Member (N) then - declare - P : constant Node_Id := Parent (N); - K : constant Node_Kind := Nkind (P); - begin - return - (K = N_Expanded_Name or else - K = N_Generic_Association or else - K = N_Parameter_Association or else - K = N_Selected_Component) - and then Selector_Name (P) = N; - end; + Kill_Current_Values_For_Entity_Chain (First_Entity (S)); - else - declare - L : constant List_Id := List_Containing (N); - P : constant Node_Id := Parent (L); - begin - return (Nkind (P) = N_Discriminant_Association - and then Selector_Names (P) = L) - or else - (Nkind (P) = N_Component_Association - and then Choices (P) = L); - end; + -- If scope is a package, also clear current values of all + -- private entities in the scope. + + if Is_Package_Or_Generic_Package (S) + or else Is_Concurrent_Type (S) + then + Kill_Current_Values_For_Entity_Chain (First_Private_Entity (S)); + end if; + + -- If this is a not a subprogram, deal with parents + + if not Is_Subprogram (S) then + S := Scope (S); + exit Scope_Loop when S = Standard_Standard; + else + exit Scope_Loop; + end if; + end loop Scope_Loop; + end Kill_Current_Values; + + -------------------------- + -- Kill_Size_Check_Code -- + -------------------------- + + procedure Kill_Size_Check_Code (E : Entity_Id) is + begin + if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable) + and then Present (Size_Check_Code (E)) + then + Remove (Size_Check_Code (E)); + Set_Size_Check_Code (E, Empty); end if; - end Is_Selector_Name; + end Kill_Size_Check_Code; - ------------------ - -- Is_Statement -- - ------------------ + -------------------------- + -- Known_To_Be_Assigned -- + -------------------------- + + function Known_To_Be_Assigned (N : Node_Id) return Boolean is + P : constant Node_Id := Parent (N); - function Is_Statement (N : Node_Id) return Boolean is begin - return - Nkind (N) in N_Statement_Other_Than_Procedure_Call - or else Nkind (N) = N_Procedure_Call_Statement; - end Is_Statement; + case Nkind (P) is - ----------------- - -- Is_Transfer -- - ----------------- + -- Test left side of assignment - function Is_Transfer (N : Node_Id) return Boolean is - Kind : constant Node_Kind := Nkind (N); + when N_Assignment_Statement => + return N = Name (P); - begin - if Kind = N_Return_Statement - or else - Kind = N_Goto_Statement - or else - Kind = N_Raise_Statement - or else - Kind = N_Requeue_Statement - then - return True; + -- Function call arguments are never lvalues - elsif (Kind = N_Exit_Statement or else Kind in N_Raise_xxx_Error) - and then No (Condition (N)) - then - return True; + when N_Function_Call => + return False; - elsif Kind = N_Procedure_Call_Statement - and then Is_Entity_Name (Name (N)) - and then Present (Entity (Name (N))) - and then No_Return (Entity (Name (N))) - then - return True; + -- Positional parameter for procedure or accept call - elsif Nkind (Original_Node (N)) = N_Raise_Statement then - return True; + when N_Procedure_Call_Statement | + N_Accept_Statement + => + declare + Proc : Entity_Id; + Form : Entity_Id; + Act : Node_Id; - else - return False; - end if; - end Is_Transfer; + begin + Proc := Get_Subprogram_Entity (P); - ------------- - -- Is_True -- - ------------- + if No (Proc) then + return False; + end if; - function Is_True (U : Uint) return Boolean is - begin - return (U /= 0); - end Is_True; + -- If we are not a list member, something is strange, so + -- be conservative and return False. - ----------------- - -- Is_Variable -- - ----------------- + if not Is_List_Member (N) then + return False; + end if; - function Is_Variable (N : Node_Id) return Boolean is + -- We are going to find the right formal by stepping forward + -- through the formals, as we step backwards in the actuals. - Orig_Node : constant Node_Id := Original_Node (N); - -- We do the test on the original node, since this is basically a - -- test of syntactic categories, so it must not be disturbed by - -- whatever rewriting might have occurred. For example, an aggregate, - -- which is certainly NOT a variable, could be turned into a variable - -- by expansion. + Form := First_Formal (Proc); + Act := N; + loop + -- If no formal, something is weird, so be conservative + -- and return False. - function In_Protected_Function (E : Entity_Id) return Boolean; - -- Within a protected function, the private components of the - -- enclosing protected type are constants. A function nested within - -- a (protected) procedure is not itself protected. + if No (Form) then + return False; + end if; - function Is_Variable_Prefix (P : Node_Id) return Boolean; - -- Prefixes can involve implicit dereferences, in which case we - -- must test for the case of a reference of a constant access - -- type, which can never be a variable. + Prev (Act); + exit when No (Act); + Next_Formal (Form); + end loop; - --------------------------- - -- In_Protected_Function -- - --------------------------- + return Ekind (Form) /= E_In_Parameter; + end; - function In_Protected_Function (E : Entity_Id) return Boolean is - Prot : constant Entity_Id := Scope (E); - S : Entity_Id; + -- Named parameter for procedure or accept call - begin - if not Is_Protected_Type (Prot) then - return False; - else - S := Current_Scope; - while Present (S) and then S /= Prot loop - if Ekind (S) = E_Function - and then Scope (S) = Prot - then - return True; - end if; + when N_Parameter_Association => + declare + Proc : Entity_Id; + Form : Entity_Id; - S := Scope (S); - end loop; + begin + Proc := Get_Subprogram_Entity (Parent (P)); - return False; - end if; - end In_Protected_Function; + if No (Proc) then + return False; + end if; - ------------------------ - -- Is_Variable_Prefix -- - ------------------------ + -- Loop through formals to find the one that matches - function Is_Variable_Prefix (P : Node_Id) return Boolean is - begin - if Is_Access_Type (Etype (P)) then - return not Is_Access_Constant (Root_Type (Etype (P))); + Form := First_Formal (Proc); + loop + -- If no matching formal, that's peculiar, some kind of + -- previous error, so return False to be conservative. - -- For the case of an indexed component whose prefix has a packed - -- array type, the prefix has been rewritten into a type conversion. - -- Determine variable-ness from the converted expression. + if No (Form) then + return False; + end if; - elsif Nkind (P) = N_Type_Conversion - and then not Comes_From_Source (P) - and then Is_Array_Type (Etype (P)) - and then Is_Packed (Etype (P)) - then - return Is_Variable (Expression (P)); + -- Else test for match - else - return Is_Variable (P); - end if; - end Is_Variable_Prefix; + if Chars (Form) = Chars (Selector_Name (P)) then + return Ekind (Form) /= E_In_Parameter; + end if; - -- Start of processing for Is_Variable + Next_Formal (Form); + end loop; + end; - begin - -- Definitely OK if Assignment_OK is set. Since this is something that - -- only gets set for expanded nodes, the test is on N, not Orig_Node. + -- Test for appearing in a conversion that itself appears + -- in an lvalue context, since this should be an lvalue. - if Nkind (N) in N_Subexpr and then Assignment_OK (N) then - return True; + when N_Type_Conversion => + return Known_To_Be_Assigned (P); - -- Normally we go to the original node, but there is one exception - -- where we use the rewritten node, namely when it is an explicit - -- dereference. The generated code may rewrite a prefix which is an - -- access type with an explicit dereference. The dereference is a - -- variable, even though the original node may not be (since it could - -- be a constant of the access type). + -- All other references are definitely not known to be modifications - elsif Nkind (N) = N_Explicit_Dereference - and then Nkind (Orig_Node) /= N_Explicit_Dereference - and then Is_Access_Type (Etype (Orig_Node)) - then - return Is_Variable_Prefix (Original_Node (Prefix (N))); + when others => + return False; - -- A function call is never a variable + end case; + end Known_To_Be_Assigned; - elsif Nkind (N) = N_Function_Call then - return False; + ------------------- + -- May_Be_Lvalue -- + ------------------- - -- All remaining checks use the original node + function May_Be_Lvalue (N : Node_Id) return Boolean is + P : constant Node_Id := Parent (N); - elsif Is_Entity_Name (Orig_Node) then - declare - E : constant Entity_Id := Entity (Orig_Node); - K : constant Entity_Kind := Ekind (E); + begin + case Nkind (P) is - begin - return (K = E_Variable - and then Nkind (Parent (E)) /= N_Exception_Handler) - or else (K = E_Component - and then not In_Protected_Function (E)) - or else K = E_Out_Parameter - or else K = E_In_Out_Parameter - or else K = E_Generic_In_Out_Parameter + -- Test left side of assignment - -- Current instance of type: + when N_Assignment_Statement => + return N = Name (P); - or else (Is_Type (E) and then In_Open_Scopes (E)) - or else (Is_Incomplete_Or_Private_Type (E) - and then In_Open_Scopes (Full_View (E))); - end; + -- Test prefix of component or attribute - else - case Nkind (Orig_Node) is - when N_Indexed_Component | N_Slice => - return Is_Variable_Prefix (Prefix (Orig_Node)); + when N_Attribute_Reference => + return N = Prefix (P) + and then Name_Implies_Lvalue_Prefix (Attribute_Name (P)); - when N_Selected_Component => - return Is_Variable_Prefix (Prefix (Orig_Node)) - and then Is_Variable (Selector_Name (Orig_Node)); + when N_Expanded_Name | + N_Explicit_Dereference | + N_Indexed_Component | + N_Reference | + N_Selected_Component | + N_Slice => + return N = Prefix (P); - -- For an explicit dereference, the type of the prefix cannot - -- be an access to constant or an access to subprogram. + -- Function call arguments are never lvalues - when N_Explicit_Dereference => - declare - Typ : constant Entity_Id := Etype (Prefix (Orig_Node)); - begin - return Is_Access_Type (Typ) - and then not Is_Access_Constant (Root_Type (Typ)) - and then Ekind (Typ) /= E_Access_Subprogram_Type; - end; + when N_Function_Call => + return False; - -- The type conversion is the case where we do not deal with the - -- context dependent special case of an actual parameter. Thus - -- the type conversion is only considered a variable for the - -- purposes of this routine if the target type is tagged. However, - -- a type conversion is considered to be a variable if it does not - -- come from source (this deals for example with the conversions - -- of expressions to their actual subtypes). + -- Positional parameter for procedure, entry, or accept call - when N_Type_Conversion => - return Is_Variable (Expression (Orig_Node)) - and then - (not Comes_From_Source (Orig_Node) - or else - (Is_Tagged_Type (Etype (Subtype_Mark (Orig_Node))) - and then - Is_Tagged_Type (Etype (Expression (Orig_Node))))); + when N_Procedure_Call_Statement | + N_Entry_Call_Statement | + N_Accept_Statement + => + declare + Proc : Entity_Id; + Form : Entity_Id; + Act : Node_Id; - -- GNAT allows an unchecked type conversion as a variable. This - -- only affects the generation of internal expanded code, since - -- calls to instantiations of Unchecked_Conversion are never - -- considered variables (since they are function calls). - -- This is also true for expression actions. + begin + Proc := Get_Subprogram_Entity (P); - when N_Unchecked_Type_Conversion => - return Is_Variable (Expression (Orig_Node)); + if No (Proc) then + return True; + end if; - when others => - return False; - end case; - end if; - end Is_Variable; + -- If we are not a list member, something is strange, so + -- be conservative and return True. - ------------------------ - -- Is_Volatile_Object -- - ------------------------ + if not Is_List_Member (N) then + return True; + end if; - function Is_Volatile_Object (N : Node_Id) return Boolean is + -- We are going to find the right formal by stepping forward + -- through the formals, as we step backwards in the actuals. - function Object_Has_Volatile_Components (N : Node_Id) return Boolean; - -- Determines if given object has volatile components + Form := First_Formal (Proc); + Act := N; + loop + -- If no formal, something is weird, so be conservative + -- and return True. - function Is_Volatile_Prefix (N : Node_Id) return Boolean; - -- If prefix is an implicit dereference, examine designated type + if No (Form) then + return True; + end if; - ------------------------ - -- Is_Volatile_Prefix -- - ------------------------ + Prev (Act); + exit when No (Act); + Next_Formal (Form); + end loop; - function Is_Volatile_Prefix (N : Node_Id) return Boolean is - Typ : constant Entity_Id := Etype (N); + return Ekind (Form) /= E_In_Parameter; + end; - begin - if Is_Access_Type (Typ) then + -- Named parameter for procedure or accept call + + when N_Parameter_Association => declare - Dtyp : constant Entity_Id := Designated_Type (Typ); + Proc : Entity_Id; + Form : Entity_Id; begin - return Is_Volatile (Dtyp) - or else Has_Volatile_Components (Dtyp); - end; + Proc := Get_Subprogram_Entity (Parent (P)); - else - return Object_Has_Volatile_Components (N); - end if; - end Is_Volatile_Prefix; + if No (Proc) then + return True; + end if; - ------------------------------------ - -- Object_Has_Volatile_Components -- - ------------------------------------ + -- Loop through formals to find the one that matches - function Object_Has_Volatile_Components (N : Node_Id) return Boolean is - Typ : constant Entity_Id := Etype (N); + Form := First_Formal (Proc); + loop + -- If no matching formal, that's peculiar, some kind of + -- previous error, so return True to be conservative. - begin - if Is_Volatile (Typ) - or else Has_Volatile_Components (Typ) - then - return True; + if No (Form) then + return True; + end if; - elsif Is_Entity_Name (N) - and then (Has_Volatile_Components (Entity (N)) - or else Is_Volatile (Entity (N))) - then - return True; + -- Else test for match - elsif Nkind (N) = N_Indexed_Component - or else Nkind (N) = N_Selected_Component - then - return Is_Volatile_Prefix (Prefix (N)); + if Chars (Form) = Chars (Selector_Name (P)) then + return Ekind (Form) /= E_In_Parameter; + end if; - else - return False; - end if; - end Object_Has_Volatile_Components; + Next_Formal (Form); + end loop; + end; - -- Start of processing for Is_Volatile_Object + -- Test for appearing in a conversion that itself appears in an + -- lvalue context, since this should be an lvalue. - begin - if Is_Volatile (Etype (N)) - or else (Is_Entity_Name (N) and then Is_Volatile (Entity (N))) - then - return True; + when N_Type_Conversion => + return May_Be_Lvalue (P); - elsif Nkind (N) = N_Indexed_Component - or else Nkind (N) = N_Selected_Component - then - return Is_Volatile_Prefix (Prefix (N)); + -- Test for appearance in object renaming declaration - else - return False; - end if; - end Is_Volatile_Object; + when N_Object_Renaming_Declaration => + return True; - ------------------------- - -- Kill_Current_Values -- - ------------------------- + -- All other references are definitely not Lvalues - procedure Kill_Current_Values is - S : Entity_Id; + when others => + return False; - procedure Kill_Current_Values_For_Entity_Chain (E : Entity_Id); - -- Clear current value for entity E and all entities chained to E + end case; + end May_Be_Lvalue; - ------------------------------------------ - -- Kill_Current_Values_For_Entity_Chain -- - ------------------------------------------ + ----------------------- + -- Mark_Coextensions -- + ----------------------- - procedure Kill_Current_Values_For_Entity_Chain (E : Entity_Id) is - Ent : Entity_Id; + procedure Mark_Coextensions (Context_Nod : Node_Id; Root_Nod : Node_Id) is + Is_Dynamic : Boolean; + -- Indicates whether the context causes nested coextensions to be + -- dynamic or static - begin - Ent := E; - while Present (Ent) loop - if Is_Object (Ent) then - Set_Current_Value (Ent, Empty); + function Mark_Allocator (N : Node_Id) return Traverse_Result; + -- Recognize an allocator node and label it as a dynamic coextension - if not Can_Never_Be_Null (Ent) then - Set_Is_Known_Non_Null (Ent, False); - end if; + -------------------- + -- Mark_Allocator -- + -------------------- + + function Mark_Allocator (N : Node_Id) return Traverse_Result is + begin + if Nkind (N) = N_Allocator then + if Is_Dynamic then + Set_Is_Dynamic_Coextension (N); + else + Set_Is_Static_Coextension (N); end if; + end if; - Next_Entity (Ent); - end loop; - end Kill_Current_Values_For_Entity_Chain; + return OK; + end Mark_Allocator; - -- Start of processing for Kill_Current_Values + procedure Mark_Allocators is new Traverse_Proc (Mark_Allocator); - begin - -- Kill all saved checks, a special case of killing saved values + -- Start of processing Mark_Coextensions - Kill_All_Checks; + begin + case Nkind (Context_Nod) is + when N_Assignment_Statement | + N_Simple_Return_Statement => + Is_Dynamic := Nkind (Expression (Context_Nod)) = N_Allocator; - -- Loop through relevant scopes, which includes the current scope and - -- any parent scopes if the current scope is a block or a package. + when N_Object_Declaration => + Is_Dynamic := Nkind (Root_Nod) = N_Allocator; - S := Current_Scope; - Scope_Loop : loop + -- This routine should not be called for constructs which may not + -- contain coextensions. - -- Clear current values of all entities in current scope + when others => + raise Program_Error; + end case; - Kill_Current_Values_For_Entity_Chain (First_Entity (S)); + Mark_Allocators (Root_Nod); + end Mark_Coextensions; - -- If scope is a package, also clear current values of all - -- private entities in the scope. + ---------------------- + -- Needs_One_Actual -- + ---------------------- - if Ekind (S) = E_Package - or else - Ekind (S) = E_Generic_Package - or else - Is_Concurrent_Type (S) - then - Kill_Current_Values_For_Entity_Chain (First_Private_Entity (S)); - end if; + function Needs_One_Actual (E : Entity_Id) return Boolean is + Formal : Entity_Id; - -- If this is a block or nested package, deal with parent + begin + if Ada_Version >= Ada_05 + and then Present (First_Formal (E)) + then + Formal := Next_Formal (First_Formal (E)); + while Present (Formal) loop + if No (Default_Value (Formal)) then + return False; + end if; - if Ekind (S) = E_Block - or else (Ekind (S) = E_Package - and then not Is_Library_Level_Entity (S)) - then - S := Scope (S); - else - exit Scope_Loop; - end if; - end loop Scope_Loop; - end Kill_Current_Values; + Next_Formal (Formal); + end loop; - -------------------------- - -- Kill_Size_Check_Code -- - -------------------------- + return True; - procedure Kill_Size_Check_Code (E : Entity_Id) is - begin - if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable) - and then Present (Size_Check_Code (E)) - then - Remove (Size_Check_Code (E)); - Set_Size_Check_Code (E, Empty); + else + return False; end if; - end Kill_Size_Check_Code; + end Needs_One_Actual; ------------------------- -- New_External_Entity -- @@ -5036,14 +7459,14 @@ package body Sem_Util is N : Node_Id; begin - -- If we are pointing at a positional parameter, it is a member of - -- a node list (the list of parameters), and the next parameter - -- is the next node on the list, unless we hit a parameter - -- association, in which case we shift to using the chain whose - -- head is the First_Named_Actual in the parent, and then is - -- threaded using the Next_Named_Actual of the Parameter_Association. - -- All this fiddling is because the original node list is in the - -- textual call order, and what we need is the declaration order. + -- If we are pointing at a positional parameter, it is a member of a + -- node list (the list of parameters), and the next parameter is the + -- next node on the list, unless we hit a parameter association, then + -- we shift to using the chain whose head is the First_Named_Actual in + -- the parent, and then is threaded using the Next_Named_Actual of the + -- Parameter_Association. All this fiddling is because the original node + -- list is in the textual call order, and what we need is the + -- declaration order. if Is_List_Member (Actual_Id) then N := Next (Actual_Id); @@ -5068,26 +7491,26 @@ package body Sem_Util is -- Normalize_Actuals -- ----------------------- - -- Chain actuals according to formals of subprogram. If there are - -- no named associations, the chain is simply the list of Parameter - -- Associations, since the order is the same as the declaration order. - -- If there are named associations, then the First_Named_Actual field - -- in the N_Procedure_Call_Statement node or N_Function_Call node - -- points to the Parameter_Association node for the parameter that - -- comes first in declaration order. The remaining named parameters - -- are then chained in declaration order using Next_Named_Actual. + -- Chain actuals according to formals of subprogram. If there are no named + -- associations, the chain is simply the list of Parameter Associations, + -- since the order is the same as the declaration order. If there are named + -- associations, then the First_Named_Actual field in the N_Function_Call + -- or N_Procedure_Call_Statement node points to the Parameter_Association + -- node for the parameter that comes first in declaration order. The + -- remaining named parameters are then chained in declaration order using + -- Next_Named_Actual. - -- This routine also verifies that the number of actuals is compatible - -- with the number and default values of formals, but performs no type - -- checking (type checking is done by the caller). + -- This routine also verifies that the number of actuals is compatible with + -- the number and default values of formals, but performs no type checking + -- (type checking is done by the caller). - -- If the matching succeeds, Success is set to True, and the caller - -- proceeds with type-checking. If the match is unsuccessful, then - -- Success is set to False, and the caller attempts a different - -- interpretation, if there is one. + -- If the matching succeeds, Success is set to True and the caller proceeds + -- with type-checking. If the match is unsuccessful, then Success is set to + -- False, and the caller attempts a different interpretation, if there is + -- one. - -- If the flag Report is on, the call is not overloaded, and a failure - -- to match can be reported here, rather than in the caller. + -- If the flag Report is on, the call is not overloaded, and a failure to + -- match can be reported here, rather than in the caller. procedure Normalize_Actuals (N : Node_Id; @@ -5096,7 +7519,7 @@ package body Sem_Util is Success : out Boolean) is Actuals : constant List_Id := Parameter_Associations (N); - Actual : Node_Id := Empty; + Actual : Node_Id := Empty; Formal : Entity_Id; Last : Node_Id := Empty; First_Named : Node_Id := Empty; @@ -5234,9 +7657,9 @@ package body Sem_Util is Formal := First_Formal (S); while Present (Formal) loop - -- Match the formals in order. If the corresponding actual - -- is positional, nothing to do. Else scan the list of named - -- actuals to find the one with the right name. + -- Match the formals in order. If the corresponding actual is + -- positional, nothing to do. Else scan the list of named actuals + -- to find the one with the right name. if Present (Actual) and then Nkind (Actual) /= N_Parameter_Association @@ -5251,7 +7674,6 @@ package body Sem_Util is Actual := First_Named; Found := False; - while Present (Actual) loop if Chars (Selector_Name (Actual)) = Chars (Formal) then Found := True; @@ -5321,7 +7743,7 @@ package body Sem_Util is Next_Formal (Formal); end loop; - if Formals_To_Match = 0 and then Actuals_To_Match = 0 then + if Formals_To_Match = 0 and then Actuals_To_Match = 0 then Success := True; return; @@ -5332,7 +7754,6 @@ package body Sem_Util is -- attached to the list of associations. Actual := First (Actuals); - while Present (Actual) loop if Nkind (Actual) = N_Parameter_Association and then Actual /= Last @@ -5356,7 +7777,7 @@ package body Sem_Util is -- Note_Possible_Modification -- -------------------------------- - procedure Note_Possible_Modification (N : Node_Id) is + procedure Note_Possible_Modification (N : Node_Id; Sure : Boolean) is Modification_Comes_From_Source : constant Boolean := Comes_From_Source (Parent (N)); @@ -5400,10 +7821,11 @@ package body Sem_Util is and then Nkind (Expression (Parent (Entity (P)))) = N_Reference then - -- Case of a reference to a value on which - -- side effects have been removed. + -- Case of a reference to a value on which side effects have + -- been removed. Exp := Prefix (Expression (Parent (Entity (P)))); + goto Continue; else return; @@ -5415,36 +7837,43 @@ package body Sem_Util is or else Nkind (Exp) = N_Unchecked_Type_Conversion then Exp := Expression (Exp); + goto Continue; elsif Nkind (Exp) = N_Slice or else Nkind (Exp) = N_Indexed_Component or else Nkind (Exp) = N_Selected_Component then Exp := Prefix (Exp); + goto Continue; else return; - end if; -- Now look for entity being referenced if Present (Ent) then - if Is_Object (Ent) then if Comes_From_Source (Exp) or else Modification_Comes_From_Source then + if Has_Pragma_Unmodified (Ent) then + Error_Msg_NE ("?pragma Unmodified given for &!", N, Ent); + end if; + Set_Never_Set_In_Source (Ent, False); end if; - Set_Is_True_Constant (Ent, False); - Set_Current_Value (Ent, Empty); + Set_Is_True_Constant (Ent, False); + Set_Current_Value (Ent, Empty); + Set_Is_Known_Null (Ent, False); if not Can_Never_Be_Null (Ent) then Set_Is_Known_Non_Null (Ent, False); end if; + -- Follow renaming chain + if (Ekind (Ent) = E_Variable or else Ekind (Ent) = E_Constant) and then Present (Renamed_Object (Ent)) then @@ -5459,9 +7888,40 @@ package body Sem_Util is if Modification_Comes_From_Source then Generate_Reference (Ent, Exp, 'm'); end if; + + Check_Nested_Access (Ent); end if; Kill_Checks (Ent); + + -- If we are sure this is a modification from source, and we know + -- this modifies a constant, then give an appropriate warning. + + if Overlays_Constant (Ent) + and then Modification_Comes_From_Source + and then Sure + then + declare + A : constant Node_Id := Address_Clause (Ent); + begin + if Present (A) then + declare + Exp : constant Node_Id := Expression (A); + begin + if Nkind (Exp) = N_Attribute_Reference + and then Attribute_Name (Exp) = Name_Address + and then Is_Entity_Name (Prefix (Exp)) + then + Error_Msg_Sloc := Sloc (A); + Error_Msg_NE + ("constant& may be modified via address clause#?", + N, Entity (Prefix (Exp))); + end if; + end; + end if; + end; + end if; + return; end if; end loop; @@ -5474,24 +7934,54 @@ package body Sem_Util is function Object_Access_Level (Obj : Node_Id) return Uint is E : Entity_Id; - -- Returns the static accessibility level of the view denoted - -- by Obj. Note that the value returned is the result of a - -- call to Scope_Depth. Only scope depths associated with - -- dynamic scopes can actually be returned. Since only - -- relative levels matter for accessibility checking, the fact - -- that the distance between successive levels of accessibility - -- is not always one is immaterial (invariant: if level(E2) is - -- deeper than level(E1), then Scope_Depth(E1) < Scope_Depth(E2)). + -- Returns the static accessibility level of the view denoted by Obj. Note + -- that the value returned is the result of a call to Scope_Depth. Only + -- scope depths associated with dynamic scopes can actually be returned. + -- Since only relative levels matter for accessibility checking, the fact + -- that the distance between successive levels of accessibility is not + -- always one is immaterial (invariant: if level(E2) is deeper than + -- level(E1), then Scope_Depth(E1) < Scope_Depth(E2)). + + function Reference_To (Obj : Node_Id) return Node_Id; + -- An explicit dereference is created when removing side-effects from + -- expressions for constraint checking purposes. In this case a local + -- access type is created for it. The correct access level is that of + -- the original source node. We detect this case by noting that the + -- prefix of the dereference is created by an object declaration whose + -- initial expression is a reference. + + ------------------ + -- Reference_To -- + ------------------ + + function Reference_To (Obj : Node_Id) return Node_Id is + Pref : constant Node_Id := Prefix (Obj); + begin + if Is_Entity_Name (Pref) + and then Nkind (Parent (Entity (Pref))) = N_Object_Declaration + and then Present (Expression (Parent (Entity (Pref)))) + and then Nkind (Expression (Parent (Entity (Pref)))) = N_Reference + then + return (Prefix (Expression (Parent (Entity (Pref))))); + else + return Empty; + end if; + end Reference_To; + + -- Start of processing for Object_Access_Level begin if Is_Entity_Name (Obj) then E := Entity (Obj); - -- If E is a type then it denotes a current instance. - -- For this case we add one to the normal accessibility - -- level of the type to ensure that current instances - -- are treated as always being deeper than than the level - -- of any visible named access type (see 3.10.2(21)). + if Is_Prival (E) then + E := Prival_Link (E); + end if; + + -- If E is a type then it denotes a current instance. For this case + -- we add one to the normal accessibility level of the type to ensure + -- that current instances are treated as always being deeper than + -- than the level of any visible named access type (see 3.10.2(21)). if Is_Type (E) then return Type_Access_Level (E) + 1; @@ -5531,10 +8021,9 @@ package body Sem_Util is elsif Nkind (Obj) = N_Explicit_Dereference then - -- If the prefix is a selected access discriminant then - -- we make a recursive call on the prefix, which will - -- in turn check the level of the prefix object of - -- the selected discriminant. + -- If the prefix is a selected access discriminant then we make a + -- recursive call on the prefix, which will in turn check the level + -- of the prefix object of the selected discriminant. if Nkind (Prefix (Obj)) = N_Selected_Component and then Ekind (Etype (Prefix (Obj))) = E_Anonymous_Access_Type @@ -5542,6 +8031,18 @@ package body Sem_Util is Ekind (Entity (Selector_Name (Prefix (Obj)))) = E_Discriminant then return Object_Access_Level (Prefix (Obj)); + + elsif not (Comes_From_Source (Obj)) then + declare + Ref : constant Node_Id := Reference_To (Obj); + begin + if Present (Ref) then + return Object_Access_Level (Ref); + else + return Type_Access_Level (Etype (Prefix (Obj))); + end if; + end; + else return Type_Access_Level (Etype (Prefix (Obj))); end if; @@ -5551,9 +8052,9 @@ package body Sem_Util is then return Object_Access_Level (Expression (Obj)); - -- Function results are objects, so we get either the access level - -- of the function or, in the case of an indirect call, the level of - -- of the access-to-subprogram type. + -- Function results are objects, so we get either the access level of + -- the function or, in the case of an indirect call, the level of the + -- access-to-subprogram type. elsif Nkind (Obj) = N_Function_Call then if Is_Entity_Name (Name (Obj)) then @@ -5617,9 +8118,9 @@ package body Sem_Util is and then Is_Record_Type (Full_View (Btype)) and then not Is_Frozen (Btype) then - -- To indicate that the ancestor depends on a private type, - -- the current Btype is sufficient. However, to check for - -- circular definition we must recurse on the full view. + -- To indicate that the ancestor depends on a private type, the + -- current Btype is sufficient. However, to check for circular + -- definition we must recurse on the full view. Candidate := Trace_Components (Full_View (Btype), True); @@ -5670,6 +8171,48 @@ package body Sem_Util is return Trace_Components (Type_Id, False); end Private_Component; + --------------------------- + -- Primitive_Names_Match -- + --------------------------- + + function Primitive_Names_Match (E1, E2 : Entity_Id) return Boolean is + + function Non_Internal_Name (E : Entity_Id) return Name_Id; + -- Given an internal name, returns the corresponding non-internal name + + ------------------------ + -- Non_Internal_Name -- + ------------------------ + + function Non_Internal_Name (E : Entity_Id) return Name_Id is + begin + Get_Name_String (Chars (E)); + Name_Len := Name_Len - 1; + return Name_Find; + end Non_Internal_Name; + + -- Start of processing for Primitive_Names_Match + + begin + pragma Assert (Present (E1) and then Present (E2)); + + return Chars (E1) = Chars (E2) + or else + (not Is_Internal_Name (Chars (E1)) + and then Is_Internal_Name (Chars (E2)) + and then Non_Internal_Name (E2) = Chars (E1)) + or else + (not Is_Internal_Name (Chars (E2)) + and then Is_Internal_Name (Chars (E1)) + and then Non_Internal_Name (E1) = Chars (E2)) + or else + (Is_Predefined_Dispatching_Operation (E1) + and then Is_Predefined_Dispatching_Operation (E2) + and then Same_TSS (E1, E2)) + or else + (Is_Init_Proc (E1) and then Is_Init_Proc (E2)); + end Primitive_Names_Match; + ----------------------- -- Process_End_Label -- ----------------------- @@ -5681,75 +8224,57 @@ package body Sem_Util is is Loc : Source_Ptr; Nam : Node_Id; + Scop : Entity_Id; Label_Ref : Boolean; -- Set True if reference to end label itself is required Endl : Node_Id; - -- Gets set to the operator symbol or identifier that references - -- the entity Ent. For the child unit case, this is the identifier - -- from the designator. For other cases, this is simply Endl. + -- Gets set to the operator symbol or identifier that references the + -- entity Ent. For the child unit case, this is the identifier from the + -- designator. For other cases, this is simply Endl. - procedure Generate_Parent_Ref (N : Node_Id); - -- N is an identifier node that appears as a parent unit reference - -- in the case where Ent is a child unit. This procedure generates - -- an appropriate cross-reference entry. + procedure Generate_Parent_Ref (N : Node_Id; E : Entity_Id); + -- N is an identifier node that appears as a parent unit reference in + -- the case where Ent is a child unit. This procedure generates an + -- appropriate cross-reference entry. E is the corresponding entity. ------------------------- -- Generate_Parent_Ref -- ------------------------- - procedure Generate_Parent_Ref (N : Node_Id) is - Parent_Ent : Entity_Id; - + procedure Generate_Parent_Ref (N : Node_Id; E : Entity_Id) is begin - -- Search up scope stack. The reason we do this is that normal - -- visibility analysis would not work for two reasons. First in - -- some subunit cases, the entry for the parent unit may not be - -- visible, and in any case there can be a local entity that - -- hides the scope entity. - - Parent_Ent := Current_Scope; - while Present (Parent_Ent) loop - if Chars (Parent_Ent) = Chars (N) then - - -- Generate the reference. We do NOT consider this as a - -- reference for unreferenced symbol purposes, but we do - -- force a cross-reference even if the end line does not - -- come from source (the caller already generated the - -- appropriate Typ for this situation). - - Generate_Reference - (Parent_Ent, N, 'r', Set_Ref => False, Force => True); - Style.Check_Identifier (N, Parent_Ent); - return; - end if; + -- If names do not match, something weird, skip reference - Parent_Ent := Scope (Parent_Ent); - end loop; + if Chars (E) = Chars (N) then - -- Fall through means entity was not found -- that's odd, but - -- the appropriate thing is simply to ignore and not generate - -- any cross-reference for this entry. + -- Generate the reference. We do NOT consider this as a reference + -- for unreferenced symbol purposes. - return; + Generate_Reference (E, N, 'r', Set_Ref => False, Force => True); + + if Style_Check then + Style.Check_Identifier (N, E); + end if; + end if; end Generate_Parent_Ref; -- Start of processing for Process_End_Label begin - -- If no node, ignore. This happens in some error situations, - -- and also for some internally generated structures where no - -- end label references are required in any case. + -- If no node, ignore. This happens in some error situations, and + -- also for some internally generated structures where no end label + -- references are required in any case. if No (N) then return; end if; -- Nothing to do if no End_Label, happens for internally generated - -- constructs where we don't want an end label reference anyway. - -- Also nothing to do if Endl is a string literal, which means - -- there was some prior error (bad operator symbol) + -- constructs where we don't want an end label reference anyway. Also + -- nothing to do if Endl is a string literal, which means there was + -- some prior error (bad operator symbol) Endl := End_Label (N); @@ -5761,10 +8286,10 @@ package body Sem_Util is if not In_Extended_Main_Source_Unit (N) then - -- Generally we do not collect references except for the - -- extended main source unit. The one exception is the 'e' - -- entry for a package spec, where it is useful for a client - -- to have the ending information to define scopes. + -- Generally we do not collect references except for the extended + -- main source unit. The one exception is the 'e' entry for a + -- package spec, where it is useful for a client to have the + -- ending information to define scopes. if Typ /= 'e' then return; @@ -5772,8 +8297,8 @@ package body Sem_Util is else Label_Ref := False; - -- For this case, we can ignore any parent references, - -- but we need the package name itself for the 'e' entry. + -- For this case, we can ignore any parent references, but we + -- need the package name itself for the 'e' entry. if Nkind (Endl) = N_Designator then Endl := Identifier (Endl); @@ -5789,17 +8314,23 @@ package body Sem_Util is if Nkind (Endl) = N_Designator then - -- Generate references for the prefix if the END line comes - -- from source (otherwise we do not need these references) + -- Generate references for the prefix if the END line comes from + -- source (otherwise we do not need these references) We climb the + -- scope stack to find the expected entities. if Comes_From_Source (Endl) then - Nam := Name (Endl); + Nam := Name (Endl); + Scop := Current_Scope; while Nkind (Nam) = N_Selected_Component loop - Generate_Parent_Ref (Selector_Name (Nam)); + Scop := Scope (Scop); + exit when No (Scop); + Generate_Parent_Ref (Selector_Name (Nam), Scop); Nam := Prefix (Nam); end loop; - Generate_Parent_Ref (Nam); + if Present (Scop) then + Generate_Parent_Ref (Nam, Scope (Scop)); + end if; end if; Endl := Identifier (Endl); @@ -5815,21 +8346,22 @@ package body Sem_Util is return; end if; - -- If label was really there, then generate a normal reference - -- and then adjust the location in the end label to point past - -- the name (which should almost always be the semicolon). + -- If label was really there, then generate a normal reference and then + -- adjust the location in the end label to point past the name (which + -- should almost always be the semicolon). Loc := Sloc (Endl); if Comes_From_Source (Endl) then - -- If a label reference is required, then do the style check - -- and generate an l-type cross-reference entry for the label + -- If a label reference is required, then do the style check and + -- generate an l-type cross-reference entry for the label if Label_Ref then if Style_Check then Style.Check_Identifier (Endl, Ent); end if; + Generate_Reference (Ent, Endl, 'l', Set_Ref => False); end if; @@ -5890,6 +8422,32 @@ package body Sem_Util is return Token_Node; end Real_Convert; + -------------------- + -- Remove_Homonym -- + -------------------- + + procedure Remove_Homonym (E : Entity_Id) is + Prev : Entity_Id := Empty; + H : Entity_Id; + + begin + if E = Current_Entity (E) then + if Present (Homonym (E)) then + Set_Current_Entity (Homonym (E)); + else + Set_Name_Entity_Id (Chars (E), Empty); + end if; + else + H := Current_Entity (E); + while Present (H) and then H /= E loop + Prev := H; + H := Homonym (H); + end loop; + + Set_Homonym (Prev, Homonym (E)); + end if; + end Remove_Homonym; + --------------------- -- Rep_To_Pos_Flag -- --------------------- @@ -5961,44 +8519,27 @@ package body Sem_Util is elsif Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then - return True; + return not Is_Value_Type (Typ); -- Record type - elsif Is_Record_Type (Typ) then - - -- In GCC 2, discriminated records always require a transient - -- scope because the back end otherwise tries to allocate a - -- variable length temporary for the particular variant. - - if Opt.GCC_Version = 2 - and then Has_Discriminants (Typ) - then - return True; - - -- For GCC 3, or for a non-discriminated record in GCC 2, we are - -- OK if none of the component types requires a transient scope. - -- Note that we already know that this is a definite type (i.e. - -- has discriminant defaults if it is a discriminated record). - - else - declare - Comp : Entity_Id; - begin - Comp := First_Entity (Typ); - while Present (Comp) loop - if Ekind (Comp) = E_Component - and then Requires_Transient_Scope (Etype (Comp)) - then - return True; - else - Next_Entity (Comp); - end if; - end loop; - end; - - return False; - end if; + elsif Is_Record_Type (Typ) then + declare + Comp : Entity_Id; + begin + Comp := First_Entity (Typ); + while Present (Comp) loop + if Ekind (Comp) = E_Component + and then Requires_Transient_Scope (Etype (Comp)) + then + return True; + else + Next_Entity (Comp); + end if; + end loop; + end; + + return False; -- String literal types never require transient scope @@ -6035,20 +8576,17 @@ package body Sem_Util is procedure Reset_Analyzed_Flags (N : Node_Id) is - function Clear_Analyzed - (N : Node_Id) return Traverse_Result; + function Clear_Analyzed (N : Node_Id) return Traverse_Result; -- Function used to reset Analyzed flags in tree. Note that we do -- not reset Analyzed flags in entities, since there is no need to - -- renalalyze entities, and indeed, it is wrong to do so, since it + -- reanalyze entities, and indeed, it is wrong to do so, since it -- can result in generating auxiliary stuff more than once. -------------------- -- Clear_Analyzed -- -------------------- - function Clear_Analyzed - (N : Node_Id) return Traverse_Result - is + function Clear_Analyzed (N : Node_Id) return Traverse_Result is begin if not Has_Extension (N) then Set_Analyzed (N, False); @@ -6057,16 +8595,12 @@ package body Sem_Util is return OK; end Clear_Analyzed; - function Reset_Analyzed is - new Traverse_Func (Clear_Analyzed); - - Discard : Traverse_Result; - pragma Warnings (Off, Discard); + procedure Reset_Analyzed is new Traverse_Proc (Clear_Analyzed); -- Start of processing for Reset_Analyzed_Flags begin - Discard := Reset_Analyzed (N); + Reset_Analyzed (N); end Reset_Analyzed_Flags; --------------------------- @@ -6074,32 +8608,67 @@ package body Sem_Util is --------------------------- function Safe_To_Capture_Value - (N : Node_Id; - Ent : Entity_Id) return Boolean + (N : Node_Id; + Ent : Entity_Id; + Cond : Boolean := False) return Boolean is begin - -- The only entities for which we track constant values are variables, - -- out parameters and in out parameters, so check if we have this case. + -- The only entities for which we track constant values are variables + -- which are not renamings, constants, out parameters, and in out + -- parameters, so check if we have this case. - if Ekind (Ent) /= E_Variable - and then - Ekind (Ent) /= E_Out_Parameter - and then - Ekind (Ent) /= E_In_Out_Parameter + -- Note: it may seem odd to track constant values for constants, but in + -- fact this routine is used for other purposes than simply capturing + -- the value. In particular, the setting of Known[_Non]_Null. + + if (Ekind (Ent) = E_Variable and then No (Renamed_Object (Ent))) + or else + Ekind (Ent) = E_Constant + or else + Ekind (Ent) = E_Out_Parameter + or else + Ekind (Ent) = E_In_Out_Parameter + then + null; + + -- For conditionals, we also allow loop parameters and all formals, + -- including in parameters. + + elsif Cond + and then + (Ekind (Ent) = E_Loop_Parameter + or else + Ekind (Ent) = E_In_Parameter) then + null; + + -- For all other cases, not just unsafe, but impossible to capture + -- Current_Value, since the above are the only entities which have + -- Current_Value fields. + + else return False; end if; - -- Skip volatile and aliased variables, since funny things might - -- be going on in these cases which we cannot necessarily track. - - if Treat_As_Volatile (Ent) or else Is_Aliased (Ent) then + -- Skip if volatile or aliased, since funny things might be going on in + -- these cases which we cannot necessarily track. Also skip any variable + -- for which an address clause is given, or whose address is taken. Also + -- never capture value of library level variables (an attempt to do so + -- can occur in the case of package elaboration code). + + if Treat_As_Volatile (Ent) + or else Is_Aliased (Ent) + or else Present (Address_Clause (Ent)) + or else Address_Taken (Ent) + or else (Is_Library_Level_Entity (Ent) + and then Ekind (Ent) = E_Variable) + then return False; end if; - -- OK, all above conditions are met. We also require that the scope - -- of the reference be the same as the scope of the entity, not - -- counting packages and blocks. + -- OK, all above conditions are met. We also require that the scope of + -- the reference be the same as the scope of the entity, not counting + -- packages and blocks and loops. declare E_Scope : constant Entity_Id := Scope (Ent); @@ -6111,8 +8680,10 @@ package body Sem_Util is exit when R_Scope = E_Scope; if Ekind (R_Scope) /= E_Package - and then - Ekind (R_Scope) /= E_Block + and then + Ekind (R_Scope) /= E_Block + and then + Ekind (R_Scope) /= E_Loop then return False; else @@ -6123,31 +8694,36 @@ package body Sem_Util is -- We also require that the reference does not appear in a context -- where it is not sure to be executed (i.e. a conditional context - -- or an exception handler). + -- or an exception handler). We skip this if Cond is True, since the + -- capturing of values from conditional tests handles this ok. + + if Cond then + return True; + end if; declare - P : Node_Id; + Desc : Node_Id; + P : Node_Id; begin + Desc := N; + P := Parent (N); while Present (P) loop if Nkind (P) = N_If_Statement - or else - Nkind (P) = N_Case_Statement - or else - Nkind (P) = N_Exception_Handler - or else - Nkind (P) = N_Selective_Accept - or else - Nkind (P) = N_Conditional_Entry_Call - or else - Nkind (P) = N_Timed_Entry_Call - or else - Nkind (P) = N_Asynchronous_Select + or else Nkind (P) = N_Case_Statement + or else (Nkind (P) = N_And_Then and then Desc = Right_Opnd (P)) + or else (Nkind (P) = N_Or_Else and then Desc = Right_Opnd (P)) + or else Nkind (P) = N_Exception_Handler + or else Nkind (P) = N_Selective_Accept + or else Nkind (P) = N_Conditional_Entry_Call + or else Nkind (P) = N_Timed_Entry_Call + or else Nkind (P) = N_Asynchronous_Select then return False; else - P := Parent (P); + Desc := P; + P := Parent (P); end if; end loop; end; @@ -6182,6 +8758,84 @@ package body Sem_Util is end if; end Same_Name; + ----------------- + -- Same_Object -- + ----------------- + + function Same_Object (Node1, Node2 : Node_Id) return Boolean is + N1 : constant Node_Id := Original_Node (Node1); + N2 : constant Node_Id := Original_Node (Node2); + -- We do the tests on original nodes, since we are most interested + -- in the original source, not any expansion that got in the way. + + K1 : constant Node_Kind := Nkind (N1); + K2 : constant Node_Kind := Nkind (N2); + + begin + -- First case, both are entities with same entity + + if K1 in N_Has_Entity + and then K2 in N_Has_Entity + and then Present (Entity (N1)) + and then Present (Entity (N2)) + and then (Ekind (Entity (N1)) = E_Variable + or else + Ekind (Entity (N1)) = E_Constant) + and then Entity (N1) = Entity (N2) + then + return True; + + -- Second case, selected component with same selector, same record + + elsif K1 = N_Selected_Component + and then K2 = N_Selected_Component + and then Chars (Selector_Name (N1)) = Chars (Selector_Name (N2)) + then + return Same_Object (Prefix (N1), Prefix (N2)); + + -- Third case, indexed component with same subscripts, same array + + elsif K1 = N_Indexed_Component + and then K2 = N_Indexed_Component + and then Same_Object (Prefix (N1), Prefix (N2)) + then + declare + E1, E2 : Node_Id; + begin + E1 := First (Expressions (N1)); + E2 := First (Expressions (N2)); + while Present (E1) loop + if not Same_Value (E1, E2) then + return False; + else + Next (E1); + Next (E2); + end if; + end loop; + + return True; + end; + + -- Fourth case, slice of same array with same bounds + + elsif K1 = N_Slice + and then K2 = N_Slice + and then Nkind (Discrete_Range (N1)) = N_Range + and then Nkind (Discrete_Range (N2)) = N_Range + and then Same_Value (Low_Bound (Discrete_Range (N1)), + Low_Bound (Discrete_Range (N2))) + and then Same_Value (High_Bound (Discrete_Range (N1)), + High_Bound (Discrete_Range (N2))) + then + return Same_Name (Prefix (N1), Prefix (N2)); + + -- All other cases, not clearly the same object + + else + return False; + end if; + end Same_Object; + --------------- -- Same_Type -- --------------- @@ -6206,11 +8860,29 @@ package body Sem_Util is end if; end Same_Type; + ---------------- + -- Same_Value -- + ---------------- + + function Same_Value (Node1, Node2 : Node_Id) return Boolean is + begin + if Compile_Time_Known_Value (Node1) + and then Compile_Time_Known_Value (Node2) + and then Expr_Value (Node1) = Expr_Value (Node2) + then + return True; + elsif Same_Object (Node1, Node2) then + return True; + else + return False; + end if; + end Same_Value; + ------------------------ -- Scope_Is_Transient -- ------------------------ - function Scope_Is_Transient return Boolean is + function Scope_Is_Transient return Boolean is begin return Scope_Stack.Table (Scope_Stack.Last).Is_Transient; end Scope_Is_Transient; @@ -6255,6 +8927,22 @@ package body Sem_Util is return False; end Scope_Within_Or_Same; + -------------------- + -- Set_Convention -- + -------------------- + + procedure Set_Convention (E : Entity_Id; Val : Snames.Convention_Id) is + begin + Basic_Set_Convention (E, Val); + + if Is_Type (E) + and then Is_Access_Subprogram_Type (Base_Type (E)) + and then Has_Foreign_Convention (E) + then + Set_Can_Use_Internal_Rep (E, False); + end if; + end Set_Convention; + ------------------------ -- Set_Current_Entity -- ------------------------ @@ -6269,6 +8957,103 @@ package body Sem_Util is Set_Name_Entity_Id (Chars (E), E); end Set_Current_Entity; + --------------------------- + -- Set_Debug_Info_Needed -- + --------------------------- + + procedure Set_Debug_Info_Needed (T : Entity_Id) is + + procedure Set_Debug_Info_Needed_If_Not_Set (E : Entity_Id); + pragma Inline (Set_Debug_Info_Needed_If_Not_Set); + -- Used to set debug info in a related node if not set already + + -------------------------------------- + -- Set_Debug_Info_Needed_If_Not_Set -- + -------------------------------------- + + procedure Set_Debug_Info_Needed_If_Not_Set (E : Entity_Id) is + begin + if Present (E) + and then not Needs_Debug_Info (E) + then + Set_Debug_Info_Needed (E); + + -- For a private type, indicate that the full view also needs + -- debug information. + + if Is_Type (E) + and then Is_Private_Type (E) + and then Present (Full_View (E)) + then + Set_Debug_Info_Needed (Full_View (E)); + end if; + end if; + end Set_Debug_Info_Needed_If_Not_Set; + + -- Start of processing for Set_Debug_Info_Needed + + begin + -- Nothing to do if argument is Empty or has Debug_Info_Off set, which + -- indicates that Debug_Info_Needed is never required for the entity. + + if No (T) + or else Debug_Info_Off (T) + then + return; + end if; + + -- Set flag in entity itself. Note that we will go through the following + -- circuitry even if the flag is already set on T. That's intentional, + -- it makes sure that the flag will be set in subsidiary entities. + + Set_Needs_Debug_Info (T); + + -- Set flag on subsidiary entities if not set already + + if Is_Object (T) then + Set_Debug_Info_Needed_If_Not_Set (Etype (T)); + + elsif Is_Type (T) then + Set_Debug_Info_Needed_If_Not_Set (Etype (T)); + + if Is_Record_Type (T) then + declare + Ent : Entity_Id := First_Entity (T); + begin + while Present (Ent) loop + Set_Debug_Info_Needed_If_Not_Set (Ent); + Next_Entity (Ent); + end loop; + end; + + elsif Is_Array_Type (T) then + Set_Debug_Info_Needed_If_Not_Set (Component_Type (T)); + + declare + Indx : Node_Id := First_Index (T); + begin + while Present (Indx) loop + Set_Debug_Info_Needed_If_Not_Set (Etype (Indx)); + Indx := Next_Index (Indx); + end loop; + end; + + if Is_Packed (T) then + Set_Debug_Info_Needed_If_Not_Set (Packed_Array_Type (T)); + end if; + + elsif Is_Access_Type (T) then + Set_Debug_Info_Needed_If_Not_Set (Directly_Designated_Type (T)); + + elsif Is_Private_Type (T) then + Set_Debug_Info_Needed_If_Not_Set (Full_View (T)); + + elsif Is_Protected_Type (T) then + Set_Debug_Info_Needed_If_Not_Set (Corresponding_Record_Type (T)); + end if; + end if; + end Set_Debug_Info_Needed; + --------------------------------- -- Set_Entity_With_Style_Check -- --------------------------------- @@ -6286,20 +9071,17 @@ package body Sem_Util is then if Nkind (N) = N_Identifier then Nod := N; - elsif Nkind (N) = N_Expanded_Name then Nod := Selector_Name (N); - else return; end if; - Val_Actual := Val; - -- A special situation arises for derived operations, where we want -- to do the check against the parent (since the Sloc of the derived -- operation points to the derived type declaration itself). + Val_Actual := Val; while not Comes_From_Source (Val_Actual) and then Nkind (Val_Actual) in N_Entity and then (Ekind (Val_Actual) = E_Enumeration_Literal @@ -6342,6 +9124,19 @@ package body Sem_Util is end if; end Set_Next_Actual; + ---------------------------------- + -- Set_Optimize_Alignment_Flags -- + ---------------------------------- + + procedure Set_Optimize_Alignment_Flags (E : Entity_Id) is + begin + if Optimize_Alignment = 'S' then + Set_Optimize_Alignment_Space (E); + elsif Optimize_Alignment = 'T' then + Set_Optimize_Alignment_Time (E); + end if; + end Set_Optimize_Alignment_Flags; + ----------------------- -- Set_Public_Status -- ----------------------- @@ -6349,21 +9144,67 @@ package body Sem_Util is procedure Set_Public_Status (Id : Entity_Id) is S : constant Entity_Id := Current_Scope; + function Within_HSS_Or_If (E : Entity_Id) return Boolean; + -- Determines if E is defined within handled statement sequence or + -- an if statement, returns True if so, False otherwise. + + ---------------------- + -- Within_HSS_Or_If -- + ---------------------- + + function Within_HSS_Or_If (E : Entity_Id) return Boolean is + N : Node_Id; + begin + N := Declaration_Node (E); + loop + N := Parent (N); + + if No (N) then + return False; + + elsif Nkind_In (N, N_Handled_Sequence_Of_Statements, + N_If_Statement) + then + return True; + end if; + end loop; + end Within_HSS_Or_If; + + -- Start of processing for Set_Public_Status + begin - if S = Standard_Standard - or else (Is_Public (S) - and then (Ekind (S) = E_Package - or else Is_Record_Type (S) - or else Ekind (S) = E_Void)) + -- Everything in the scope of Standard is public + + if S = Standard_Standard then + Set_Is_Public (Id); + + -- Entity is definitely not public if enclosing scope is not public + + elsif not Is_Public (S) then + return; + + -- An object or function declaration that occurs in a handled sequence + -- of statements or within an if statement is the declaration for a + -- temporary object or local subprogram generated by the expander. It + -- never needs to be made public and furthermore, making it public can + -- cause back end problems. + + elsif Nkind_In (Parent (Id), N_Object_Declaration, + N_Function_Specification) + and then Within_HSS_Or_If (Id) then + return; + + -- Entities in public packages or records are public + + elsif Ekind (S) = E_Package or Is_Record_Type (S) then Set_Is_Public (Id); -- The bounds of an entry family declaration can generate object -- declarations that are visible to the back-end, e.g. in the -- the declaration of a composite type that contains tasks. - elsif Is_Public (S) - and then Is_Concurrent_Type (S) + elsif Is_Concurrent_Type (S) and then not Has_Completion (S) and then Nkind (Parent (Id)) = N_Object_Declaration then @@ -6371,6 +9212,42 @@ package body Sem_Util is end if; end Set_Public_Status; + ----------------------------- + -- Set_Referenced_Modified -- + ----------------------------- + + procedure Set_Referenced_Modified (N : Node_Id; Out_Param : Boolean) is + Pref : Node_Id; + + begin + -- Deal with indexed or selected component where prefix is modified + + if Nkind (N) = N_Indexed_Component + or else + Nkind (N) = N_Selected_Component + then + Pref := Prefix (N); + + -- If prefix is access type, then it is the designated object that is + -- being modified, which means we have no entity to set the flag on. + + if No (Etype (Pref)) or else Is_Access_Type (Etype (Pref)) then + return; + + -- Otherwise chase the prefix + + else + Set_Referenced_Modified (Pref, Out_Param); + end if; + + -- Otherwise see if we have an entity name (only other case to process) + + elsif Is_Entity_Name (N) and then Present (Entity (N)) then + Set_Referenced_As_LHS (Entity (N), not Out_Param); + Set_Referenced_As_Out_Parameter (Entity (N), Out_Param); + end if; + end Set_Referenced_Modified; + ---------------------------- -- Set_Scope_Is_Transient -- ---------------------------- @@ -6398,6 +9275,7 @@ package body Sem_Util is then Set_Is_Unsigned_Type (T1, Is_Unsigned_Type (T2)); end if; + Set_Alignment (T1, Alignment (T2)); end Set_Size_Info; @@ -6474,8 +9352,8 @@ package body Sem_Util is Write_Str (Msg); Write_Name (Chars (E)); - Write_Str (" line "); - Write_Int (Int (Get_Logical_Line_Number (Sloc (N)))); + Write_Str (" from "); + Write_Location (Sloc (N)); Write_Eol; end if; end Trace_Scope; @@ -6485,7 +9363,7 @@ package body Sem_Util is ----------------------- procedure Transfer_Entities (From : Entity_Id; To : Entity_Id) is - Ent : Entity_Id := First_Entity (From); + Ent : Entity_Id := First_Entity (From); begin if No (Ent) then @@ -6515,10 +9393,8 @@ package body Sem_Util is declare Comp : Entity_Id; - begin Comp := First_Entity (Ent); - while Present (Comp) loop Set_Is_Public (Comp); Next_Entity (Comp); @@ -6542,29 +9418,104 @@ package body Sem_Util is Btyp : Entity_Id; begin - -- If the type is an anonymous access type we treat it as being - -- declared at the library level to ensure that names such as - -- X.all'access don't fail static accessibility checks. - - -- Ada 2005 (AI-230): In case of anonymous access types that are - -- component_definition or discriminants of a nonlimited type, - -- the level is the same as that of the enclosing component type. - Btyp := Base_Type (Typ); + -- Ada 2005 (AI-230): For most cases of anonymous access types, we + -- simply use the level where the type is declared. This is true for + -- stand-alone object declarations, and for anonymous access types + -- associated with components the level is the same as that of the + -- enclosing composite type. However, special treatment is needed for + -- the cases of access parameters, return objects of an anonymous access + -- type, and, in Ada 95, access discriminants of limited types. + if Ekind (Btyp) in Access_Kind then - if Ekind (Btyp) = E_Anonymous_Access_Type - and then not Is_Local_Anonymous_Access (Typ) -- Ada 2005 (AI-230) - then - return Scope_Depth (Standard_Standard); + if Ekind (Btyp) = E_Anonymous_Access_Type then + + -- If the type is a nonlocal anonymous access type (such as for + -- an access parameter) we treat it as being declared at the + -- library level to ensure that names such as X.all'access don't + -- fail static accessibility checks. + + if not Is_Local_Anonymous_Access (Typ) then + return Scope_Depth (Standard_Standard); + + -- If this is a return object, the accessibility level is that of + -- the result subtype of the enclosing function. The test here is + -- little complicated, because we have to account for extended + -- return statements that have been rewritten as blocks, in which + -- case we have to find and the Is_Return_Object attribute of the + -- itype's associated object. It would be nice to find a way to + -- simplify this test, but it doesn't seem worthwhile to add a new + -- flag just for purposes of this test. ??? + + elsif Ekind (Scope (Btyp)) = E_Return_Statement + or else + (Is_Itype (Btyp) + and then Nkind (Associated_Node_For_Itype (Btyp)) = + N_Object_Declaration + and then Is_Return_Object + (Defining_Identifier + (Associated_Node_For_Itype (Btyp)))) + then + declare + Scop : Entity_Id; + + begin + Scop := Scope (Scope (Btyp)); + while Present (Scop) loop + exit when Ekind (Scop) = E_Function; + Scop := Scope (Scop); + end loop; + + -- Treat the return object's type as having the level of the + -- function's result subtype (as per RM05-6.5(5.3/2)). + + return Type_Access_Level (Etype (Scop)); + end; + end if; end if; Btyp := Root_Type (Btyp); + + -- The accessibility level of anonymous access types associated with + -- discriminants is that of the current instance of the type, and + -- that's deeper than the type itself (AARM 3.10.2 (12.3.21)). + + -- AI-402: access discriminants have accessibility based on the + -- object rather than the type in Ada 2005, so the above paragraph + -- doesn't apply. + + -- ??? Needs completion with rules from AI-416 + + if Ada_Version <= Ada_95 + and then Ekind (Typ) = E_Anonymous_Access_Type + and then Present (Associated_Node_For_Itype (Typ)) + and then Nkind (Associated_Node_For_Itype (Typ)) = + N_Discriminant_Specification + then + return Scope_Depth (Enclosing_Dynamic_Scope (Btyp)) + 1; + end if; end if; return Scope_Depth (Enclosing_Dynamic_Scope (Btyp)); end Type_Access_Level; + -------------------- + -- Ultimate_Alias -- + -------------------- + -- To do: add occurrences calling this new subprogram + + function Ultimate_Alias (Prim : Entity_Id) return Entity_Id is + E : Entity_Id := Prim; + + begin + while Present (Alias (E)) loop + E := Alias (E); + end loop; + + return E; + end Ultimate_Alias; + -------------------------- -- Unit_Declaration_Node -- -------------------------- @@ -6579,6 +9530,8 @@ package body Sem_Util is return N; end if; + -- Isn't there some better way to express the following ??? + while Nkind (N) /= N_Abstract_Subprogram_Declaration and then Nkind (N) /= N_Formal_Package_Declaration and then Nkind (N) /= N_Function_Instantiation @@ -6631,9 +9584,7 @@ package body Sem_Util is else Get_First_Interp (Opnd, Index, It); - while Present (It.Typ) loop - if It.Typ = Universal_Integer or else It.Typ = Universal_Real then @@ -6647,6 +9598,24 @@ package body Sem_Util is end if; end Universal_Interpretation; + --------------- + -- Unqualify -- + --------------- + + function Unqualify (Expr : Node_Id) return Node_Id is + begin + -- Recurse to handle unlikely case of multiple levels of qualification + + if Nkind (Expr) = N_Qualified_Expression then + return Unqualify (Expression (Expr)); + + -- Normal case, not a qualified expression + + else + return Expr; + end if; + end Unqualify; + ---------------------- -- Within_Init_Proc -- ---------------------- @@ -6751,7 +9720,6 @@ package body Sem_Util is -- There is no simple way to insure that it is consistent ??? elsif In_Instance then - if Etype (Etype (Expr)) = Etype (Expected_Type) and then (Has_Private_Declaration (Expected_Type) @@ -6789,6 +9757,29 @@ package body Sem_Util is Error_Msg_N ("result must be general access type!", Expr); Error_Msg_NE ("add ALL to }!", Expr, Expec_Type); + -- Another special check, if the expected type is an integer type, + -- but the expression is of type System.Address, and the parent is + -- an addition or subtraction operation whose left operand is the + -- expression in question and whose right operand is of an integral + -- type, then this is an attempt at address arithmetic, so give + -- appropriate message. + + elsif Is_Integer_Type (Expec_Type) + and then Is_RTE (Found_Type, RE_Address) + and then (Nkind (Parent (Expr)) = N_Op_Add + or else + Nkind (Parent (Expr)) = N_Op_Subtract) + and then Expr = Left_Opnd (Parent (Expr)) + and then Is_Integer_Type (Etype (Right_Opnd (Parent (Expr)))) + then + Error_Msg_N + ("address arithmetic not predefined in package System", + Parent (Expr)); + Error_Msg_N + ("\possible missing with/use of System.Storage_Elements", + Parent (Expr)); + return; + -- If the expected type is an anonymous access type, as for access -- parameters and discriminants, the error is on the designated types. @@ -6805,14 +9796,14 @@ package body Sem_Util is and then not Comes_From_Source (Found_Type) then Error_Msg_NE - ("found an access type with designated}!", + ("\\found an access type with designated}!", Expr, Designated_Type (Found_Type)); else if From_With_Type (Found_Type) then - Error_Msg_NE ("found incomplete}!", Expr, Found_Type); - Error_Msg_NE - ("\possibly missing with_clause on&", Expr, - Scope (Found_Type)); + Error_Msg_NE ("\\found incomplete}!", Expr, Found_Type); + Error_Msg_Qual_Level := 99; + Error_Msg_NE ("\\missing `WITH &;", Expr, Scope (Found_Type)); + Error_Msg_Qual_Level := 0; else Error_Msg_NE ("found}!", Expr, Found_Type); end if; @@ -6821,11 +9812,11 @@ package body Sem_Util is -- Normal case of one type found, some other type expected else - -- If the names of the two types are the same, see if some - -- number of levels of qualification will help. Don't try - -- more than three levels, and if we get to standard, it's - -- no use (and probably represents an error in the compiler) - -- Also do not bother with internal scope names. + -- If the names of the two types are the same, see if some number + -- of levels of qualification will help. Don't try more than three + -- levels, and if we get to standard, it's no use (and probably + -- represents an error in the compiler) Also do not bother with + -- internal scope names. declare Expec_Scope : Entity_Id; @@ -6861,9 +9852,9 @@ package body Sem_Util is end if; if Is_Entity_Name (Expr) - and then Is_Package (Entity (Expr)) + and then Is_Package_Or_Generic_Package (Entity (Expr)) then - Error_Msg_N ("found package name!", Expr); + Error_Msg_N ("\\found package name!", Expr); elsif Is_Entity_Name (Expr) and then @@ -6876,7 +9867,8 @@ package body Sem_Util is ("found procedure name, possibly missing Access attribute!", Expr); else - Error_Msg_N ("found procedure name instead of function!", Expr); + Error_Msg_N + ("\\found procedure name instead of function!", Expr); end if; elsif Nkind (Expr) = N_Function_Call @@ -6905,10 +9897,10 @@ package body Sem_Util is and then Present (Parent (Found_Type)) and then Nkind (Parent (Found_Type)) = N_Full_Type_Declaration then - Error_Msg_NE ("found premature usage of}!", Expr, Found_Type); + Error_Msg_NE ("\\found premature usage of}!", Expr, Found_Type); else - Error_Msg_NE ("found}!", Expr, Found_Type); + Error_Msg_NE ("\\found}!", Expr, Found_Type); end if; Error_Msg_Qual_Level := 0;