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------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S E M _ U T I L -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2005, 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- -- -- 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, 51 Franklin Street, Fifth Floor, -- -- Boston, MA 02110-1301, USA. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Atree; use Atree; with Casing; use Casing; with Checks; use Checks; with Debug; use Debug; with Errout; use Errout; with Elists; use Elists; 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 Restrict; use Restrict; with Rident; use Rident; with Rtsfind; use Rtsfind; with Scans; use Scans; with Scn; use Scn; with Sem; use Sem; 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; with Targparm; use Targparm; with Tbuild; use Tbuild; with Ttypes; use Ttypes; with Uname; use Uname; package body Sem_Util is ----------------------- -- Local Subprograms -- ----------------------- function Build_Component_Subtype (C : List_Id; Loc : Source_Ptr; T : Entity_Id) return Node_Id; -- This function builds the subtype for Build_Actual_Subtype_Of_Component -- and Build_Discriminal_Subtype_Of_Component. C is a list of constraints, -- Loc is the source location, T is the original subtype. function Is_Fully_Initialized_Variant (Typ : Entity_Id) return Boolean; -- Subsidiary to Is_Fully_Initialized_Type. For an unconstrained type -- with discriminants whose default values are static, examine only the -- components in the selected variant to determine whether all of them -- have a default. function Has_Null_Extension (T : Entity_Id) return Boolean; -- 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. -------------------------------- -- Add_Access_Type_To_Process -- -------------------------------- procedure Add_Access_Type_To_Process (E : Entity_Id; A : Entity_Id) is L : Elist_Id; begin Ensure_Freeze_Node (E); L := Access_Types_To_Process (Freeze_Node (E)); if No (L) then L := New_Elmt_List; Set_Access_Types_To_Process (Freeze_Node (E), L); end if; Append_Elmt (A, L); end Add_Access_Type_To_Process; ----------------------- -- Alignment_In_Bits -- ----------------------- function Alignment_In_Bits (E : Entity_Id) return Uint is begin return Alignment (E) * System_Storage_Unit; end Alignment_In_Bits; ----------------------------------------- -- Apply_Compile_Time_Constraint_Error -- ----------------------------------------- procedure Apply_Compile_Time_Constraint_Error (N : Node_Id; Msg : String; Reason : RT_Exception_Code; Ent : Entity_Id := Empty; Typ : Entity_Id := Empty; Loc : Source_Ptr := No_Location; Rep : Boolean := True; Warn : Boolean := False) is Stat : constant Boolean := Is_Static_Expression (N); Rtyp : Entity_Id; begin if No (Typ) then Rtyp := Etype (N); else Rtyp := Typ; end if; Discard_Node ( Compile_Time_Constraint_Error (N, Msg, Ent, Loc, Warn => Warn)); if not Rep then return; end if; -- 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)); Set_Analyzed (N, True); Set_Etype (N, Rtyp); Set_Raises_Constraint_Error (N); -- If the original expression was marked as static, the result is -- still marked as static, but the Raises_Constraint_Error flag is -- always set so that further static evaluation is not attempted. if Stat then Set_Is_Static_Expression (N); end if; end Apply_Compile_Time_Constraint_Error; -------------------------- -- Build_Actual_Subtype -- -------------------------- function Build_Actual_Subtype (T : Entity_Id; N : Node_Or_Entity_Id) return Node_Id is Obj : Node_Id; Loc : constant Source_Ptr := Sloc (N); Constraints : List_Id; Decl : Node_Id; Discr : Entity_Id; Hi : Node_Id; Lo : Node_Id; Subt : Entity_Id; Disc_Type : Entity_Id; begin if Nkind (N) = N_Defining_Identifier then Obj := New_Reference_To (N, Loc); 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. Lo := Make_Attribute_Reference (Loc, Prefix => Duplicate_Subexpr_No_Checks (Obj, Name_Req => True), Attribute_Name => Name_First, Expressions => New_List ( Make_Integer_Literal (Loc, J))); Hi := Make_Attribute_Reference (Loc, Prefix => Duplicate_Subexpr_No_Checks (Obj, Name_Req => True), Attribute_Name => Name_Last, Expressions => New_List ( Make_Integer_Literal (Loc, J))); Append (Make_Range (Loc, Lo, Hi), Constraints); end loop; -- If the type has unknown discriminants there is no constrained -- subtype to build. This is never called for a formal or for a -- lhs, so returning the type is ok ??? elsif Has_Unknown_Discriminants (T) then return T; else Constraints := New_List; if Is_Private_Type (T) and then No (Full_View (T)) then -- Type is a generic derived type. Inherit discriminants from -- Parent type. 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, Prefix => Duplicate_Subexpr_No_Checks (Obj), Selector_Name => New_Occurrence_Of (Discr, Loc))); Next_Discriminant (Discr); end loop; end if; Subt := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('S')); Set_Is_Internal (Subt); Decl := Make_Subtype_Declaration (Loc, Defining_Identifier => Subt, Subtype_Indication => Make_Subtype_Indication (Loc, Subtype_Mark => New_Reference_To (T, Loc), Constraint => Make_Index_Or_Discriminant_Constraint (Loc, Constraints => Constraints))); Mark_Rewrite_Insertion (Decl); return Decl; end Build_Actual_Subtype; --------------------------------------- -- Build_Actual_Subtype_Of_Component -- --------------------------------------- function Build_Actual_Subtype_Of_Component (T : Entity_Id; N : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); P : constant Node_Id := Prefix (N); D : Elmt_Id; Id : Node_Id; Indx_Type : Entity_Id; Deaccessed_T : Entity_Id; -- This is either a copy of T, or if T is an access type, then it is -- the directly designated type of this access type. function Build_Actual_Array_Constraint return List_Id; -- If one or more of the bounds of the component depends on -- discriminants, build actual constraint using the discriminants -- of the prefix. function Build_Actual_Record_Constraint return List_Id; -- Similar to previous one, for discriminated components constrained -- by the discriminant of the enclosing object. ----------------------------------- -- Build_Actual_Array_Constraint -- ----------------------------------- function Build_Actual_Array_Constraint return List_Id is Constraints : constant List_Id := New_List; Indx : Node_Id; Hi : Node_Id; Lo : Node_Id; Old_Hi : Node_Id; Old_Lo : Node_Id; begin Indx := First_Index (Deaccessed_T); while Present (Indx) loop Old_Lo := Type_Low_Bound (Etype (Indx)); Old_Hi := Type_High_Bound (Etype (Indx)); if Denotes_Discriminant (Old_Lo) then Lo := Make_Selected_Component (Loc, Prefix => New_Copy_Tree (P), Selector_Name => New_Occurrence_Of (Entity (Old_Lo), Loc)); else Lo := New_Copy_Tree (Old_Lo); -- The new bound will be reanalyzed in the enclosing -- declaration. For literal bounds that come from a type -- declaration, the type of the context must be imposed, so -- insure that analysis will take place. For non-universal -- types this is not strictly necessary. Set_Analyzed (Lo, False); end if; if Denotes_Discriminant (Old_Hi) then Hi := Make_Selected_Component (Loc, Prefix => New_Copy_Tree (P), Selector_Name => New_Occurrence_Of (Entity (Old_Hi), Loc)); else Hi := New_Copy_Tree (Old_Hi); Set_Analyzed (Hi, False); end if; Append (Make_Range (Loc, Lo, Hi), Constraints); Next_Index (Indx); end loop; return Constraints; end Build_Actual_Array_Constraint; ------------------------------------ -- Build_Actual_Record_Constraint -- ------------------------------------ function Build_Actual_Record_Constraint return List_Id is Constraints : constant List_Id := New_List; D : Elmt_Id; D_Val : Node_Id; 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), Selector_Name => New_Occurrence_Of (Entity (Node (D)), Loc)); else D_Val := New_Copy_Tree (Node (D)); end if; Append (D_Val, Constraints); Next_Elmt (D); end loop; return Constraints; end Build_Actual_Record_Constraint; -- Start of processing for Build_Actual_Subtype_Of_Component begin if In_Default_Expression then return Empty; elsif Nkind (N) = N_Explicit_Dereference then if Is_Composite_Type (T) and then not Is_Constrained (T) and then not (Is_Class_Wide_Type (T) and then Is_Constrained (Root_Type (T))) and then not Has_Unknown_Discriminants (T) then -- If the type of the dereference is already constrained, it -- is an actual subtype. if Is_Array_Type (Etype (N)) and then Is_Constrained (Etype (N)) then return Empty; else Remove_Side_Effects (P); return Build_Actual_Subtype (T, N); end if; else return Empty; end if; end if; if Ekind (T) = E_Access_Subtype then Deaccessed_T := Designated_Type (T); else Deaccessed_T := T; end if; 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 Denotes_Discriminant (Type_High_Bound (Indx_Type)) then Remove_Side_Effects (P); return Build_Component_Subtype ( Build_Actual_Array_Constraint, Loc, Base_Type (T)); end if; Next_Index (Id); end loop; elsif Is_Composite_Type (Deaccessed_T) and then Has_Discriminants (Deaccessed_T) and then not Has_Unknown_Discriminants (Deaccessed_T) then D := First_Elmt (Discriminant_Constraint (Deaccessed_T)); while Present (D) loop if Denotes_Discriminant (Node (D)) then Remove_Side_Effects (P); return Build_Component_Subtype ( Build_Actual_Record_Constraint, Loc, Base_Type (T)); end if; Next_Elmt (D); end loop; end if; -- If none of the above, the actual and nominal subtypes are the same return Empty; end Build_Actual_Subtype_Of_Component; ----------------------------- -- Build_Component_Subtype -- ----------------------------- function Build_Component_Subtype (C : List_Id; Loc : Source_Ptr; T : Entity_Id) return Node_Id is Subt : Entity_Id; Decl : Node_Id; begin -- Unchecked_Union components do not require component subtypes if Is_Unchecked_Union (T) then return Empty; end if; Subt := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('S')); Set_Is_Internal (Subt); Decl := Make_Subtype_Declaration (Loc, Defining_Identifier => Subt, Subtype_Indication => Make_Subtype_Indication (Loc, Subtype_Mark => New_Reference_To (Base_Type (T), Loc), Constraint => Make_Index_Or_Discriminant_Constraint (Loc, Constraints => C))); Mark_Rewrite_Insertion (Decl); return Decl; end Build_Component_Subtype; -------------------------------------------- -- Build_Discriminal_Subtype_Of_Component -- -------------------------------------------- function Build_Discriminal_Subtype_Of_Component (T : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (T); D : Elmt_Id; Id : Node_Id; function Build_Discriminal_Array_Constraint return List_Id; -- If one or more of the bounds of the component depends on -- discriminants, build actual constraint using the discriminants -- of the prefix. function Build_Discriminal_Record_Constraint return List_Id; -- Similar to previous one, for discriminated components constrained -- by the discriminant of the enclosing object. ---------------------------------------- -- Build_Discriminal_Array_Constraint -- ---------------------------------------- function Build_Discriminal_Array_Constraint return List_Id is Constraints : constant List_Id := New_List; Indx : Node_Id; Hi : Node_Id; Lo : Node_Id; Old_Hi : Node_Id; Old_Lo : Node_Id; begin Indx := First_Index (T); while Present (Indx) loop Old_Lo := Type_Low_Bound (Etype (Indx)); Old_Hi := Type_High_Bound (Etype (Indx)); if Denotes_Discriminant (Old_Lo) then Lo := New_Occurrence_Of (Discriminal (Entity (Old_Lo)), Loc); else Lo := New_Copy_Tree (Old_Lo); end if; if Denotes_Discriminant (Old_Hi) then Hi := New_Occurrence_Of (Discriminal (Entity (Old_Hi)), Loc); else Hi := New_Copy_Tree (Old_Hi); end if; Append (Make_Range (Loc, Lo, Hi), Constraints); Next_Index (Indx); end loop; return Constraints; end Build_Discriminal_Array_Constraint; ----------------------------------------- -- Build_Discriminal_Record_Constraint -- ----------------------------------------- function Build_Discriminal_Record_Constraint return List_Id is Constraints : constant List_Id := New_List; D : Elmt_Id; D_Val : Node_Id; begin D := First_Elmt (Discriminant_Constraint (T)); while Present (D) loop if Denotes_Discriminant (Node (D)) then D_Val := New_Occurrence_Of (Discriminal (Entity (Node (D))), Loc); else D_Val := New_Copy_Tree (Node (D)); end if; Append (D_Val, Constraints); Next_Elmt (D); end loop; return Constraints; end Build_Discriminal_Record_Constraint; -- Start of processing for Build_Discriminal_Subtype_Of_Component 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))) then return Build_Component_Subtype (Build_Discriminal_Array_Constraint, Loc, T); end if; Next_Index (Id); end loop; elsif Ekind (T) = E_Record_Subtype and then Has_Discriminants (T) and then not Has_Unknown_Discriminants (T) then D := First_Elmt (Discriminant_Constraint (T)); while Present (D) loop if Denotes_Discriminant (Node (D)) then return Build_Component_Subtype (Build_Discriminal_Record_Constraint, Loc, T); end if; Next_Elmt (D); end loop; end if; -- If none of the above, the actual and nominal subtypes are the same return Empty; end Build_Discriminal_Subtype_Of_Component; ------------------------------ -- Build_Elaboration_Entity -- ------------------------------ 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; begin -- Ignore if already constructed if Present (Elaboration_Entity (Spec_Id)) then 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 Name_Buffer (Name_Len - 1 .. Name_Len) := "_E"; -- Replace dots by double underscore 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; -- Create elaboration flag Elab_Ent := 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, Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc), Expression => New_Occurrence_Of (Standard_False, Loc)); Append_To (Declarations (Aux_Decls_Node (N)), Decl); Analyze (Decl); -- Reset True_Constant indication, since we will indeed -- assign a value to the variable in the binder main. Set_Is_True_Constant (Elab_Ent, False); Set_Current_Value (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 -- in the case of a library level generic instantiation). Set_Has_Qualified_Name (Elab_Ent); Set_Has_Fully_Qualified_Name (Elab_Ent); end Build_Elaboration_Entity; ----------------------------------- -- Cannot_Raise_Constraint_Error -- ----------------------------------- function Cannot_Raise_Constraint_Error (Expr : Node_Id) return Boolean is begin if Compile_Time_Known_Value (Expr) then return True; elsif Do_Range_Check (Expr) then return False; elsif Raises_Constraint_Error (Expr) then return False; else case Nkind (Expr) is when N_Identifier => return True; when N_Expanded_Name => return True; when N_Selected_Component => return not Do_Discriminant_Check (Expr); when N_Attribute_Reference => if Do_Overflow_Check (Expr) then return False; elsif No (Expressions (Expr)) then return True; else declare N : Node_Id := First (Expressions (Expr)); begin while Present (N) loop if Cannot_Raise_Constraint_Error (N) then Next (N); else return False; end if; end loop; return True; end; end if; when N_Type_Conversion => if Do_Overflow_Check (Expr) or else Do_Length_Check (Expr) or else Do_Tag_Check (Expr) then return False; else return Cannot_Raise_Constraint_Error (Expression (Expr)); end if; when N_Unchecked_Type_Conversion => return Cannot_Raise_Constraint_Error (Expression (Expr)); when N_Unary_Op => if Do_Overflow_Check (Expr) then return False; else return Cannot_Raise_Constraint_Error (Right_Opnd (Expr)); end if; when N_Op_Divide | N_Op_Mod | N_Op_Rem => if Do_Division_Check (Expr) or else Do_Overflow_Check (Expr) then return False; else return Cannot_Raise_Constraint_Error (Left_Opnd (Expr)) and then Cannot_Raise_Constraint_Error (Right_Opnd (Expr)); end if; when N_Op_Add | N_Op_And | N_Op_Concat | N_Op_Eq | N_Op_Expon | N_Op_Ge | N_Op_Gt | N_Op_Le | N_Op_Lt | N_Op_Multiply | N_Op_Ne | N_Op_Or | N_Op_Rotate_Left | N_Op_Rotate_Right | N_Op_Shift_Left | N_Op_Shift_Right | N_Op_Shift_Right_Arithmetic | N_Op_Subtract | N_Op_Xor => if Do_Overflow_Check (Expr) then return False; else return Cannot_Raise_Constraint_Error (Left_Opnd (Expr)) and then Cannot_Raise_Constraint_Error (Right_Opnd (Expr)); end if; when others => return False; end case; end if; end Cannot_Raise_Constraint_Error; -------------------------- -- Check_Fully_Declared -- -------------------------- procedure Check_Fully_Declared (T : Entity_Id; N : Node_Id) is begin if Ekind (T) = E_Incomplete_Type then -- Ada 2005 (AI-50217): If the type is available through a limited -- with_clause, verify that its full view has been analyzed. if From_With_Type (T) and then Present (Non_Limited_View (T)) and then Ekind (Non_Limited_View (T)) /= E_Incomplete_Type then -- The non-limited view is fully declared null; else Error_Msg_NE ("premature usage of incomplete}", N, First_Subtype (T)); end if; elsif Has_Private_Component (T) and then not Is_Generic_Type (Root_Type (T)) and then not In_Default_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. if Is_Concurrent_Type (T) and then not Comes_From_Source (T) and then Nkind (N) = N_Object_Declaration then Error_Msg_NE ("type of& has incomplete component", N, Defining_Identifier (N)); else Error_Msg_NE ("premature usage of incomplete}", N, First_Subtype (T)); end if; end if; end Check_Fully_Declared; ----------------------- -- Check_Obsolescent -- ----------------------- procedure Check_Obsolescent (Nam : Entity_Id; N : Node_Id) is W : Node_Id; begin -- Note that we always allow obsolescent references in the compiler -- itself and the run time, since we assume that we know what we are -- doing in such cases. For example the calls in Ada.Characters.Handling -- to its own obsolescent subprograms are just fine. if Is_Obsolescent (Nam) and then not GNAT_Mode then Check_Restriction (No_Obsolescent_Features, N); if Warn_On_Obsolescent_Feature then if Is_Package_Or_Generic_Package (Nam) then Error_Msg_NE ("with of obsolescent package&?", N, Nam); else Error_Msg_NE ("call to obsolescent subprogram&?", N, Nam); end if; -- Output additional warning if present W := Obsolescent_Warning (Nam); if Present (W) then Name_Buffer (1) := '|'; Name_Buffer (2) := '?'; Name_Len := 2; -- Add characters to message, and output message for J in 1 .. String_Length (Strval (W)) loop Add_Char_To_Name_Buffer ('''); Add_Char_To_Name_Buffer (Get_Character (Get_String_Char (Strval (W), J))); end loop; Error_Msg_N (Name_Buffer (1 .. Name_Len), N); end if; end if; end if; end Check_Obsolescent; ------------------------------------------ -- Check_Potentially_Blocking_Operation -- ------------------------------------------ procedure Check_Potentially_Blocking_Operation (N : Node_Id) is 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 -- Program_Error. Here we only issue a warning, since we generally -- support the use of potentially blocking operations in the absence -- of the pragma. -- Indirect blocking through a subprogram call cannot be diagnosed -- statically without interprocedural analysis, so we do not attempt -- to do it here. S := Scope (Current_Scope); while Present (S) and then S /= Standard_Standard loop if Is_Protected_Type (S) then Error_Msg_N ("potentially blocking operation in protected operation?", N); return; end if; S := Scope (S); end loop; end Check_Potentially_Blocking_Operation; --------------- -- Check_VMS -- --------------- procedure Check_VMS (Construct : Node_Id) is begin if not OpenVMS_On_Target then Error_Msg_N ("this construct is allowed only in Open'V'M'S", Construct); end if; end Check_VMS; ---------------------------------- -- 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 if Base_Type (Etype (Formal)) = B_Type then Is_Prim := True; exit; elsif Ekind (Etype (Formal)) = E_Anonymous_Access_Type and then Base_Type (Designated_Type (Etype (Formal))) = B_Type then Is_Prim := True; exit; end if; Next_Formal (Formal); end loop; end if; -- For a formal derived type, the only primitives are the -- ones inherited from the parent type. Operations appearing -- in the package declaration are not primitive for it. if Is_Prim and then (not Formal_Derived or else Present (Alias (Id))) then Append_Elmt (Id, Op_List); end if; end if; Next_Entity (Id); -- For a type declared in System, some of its operations -- may appear in the target-specific extension to System. if No (Id) and then Chars (B_Scope) = Name_System and then Scope (B_Scope) = Standard_Standard and then Present_System_Aux then B_Scope := System_Aux_Id; Id := First_Entity (System_Aux_Id); end if; end loop; end if; return Op_List; end Collect_Primitive_Operations; ----------------------------------- -- Compile_Time_Constraint_Error -- ----------------------------------- function Compile_Time_Constraint_Error (N : Node_Id; Msg : String; Ent : Entity_Id := Empty; Loc : Source_Ptr := No_Location; Warn : Boolean := False) return Node_Id is Msgc : String (1 .. Msg'Length + 2); Msgl : Natural; Wmsg : Boolean; P : Node_Id; Msgs : Boolean; Eloc : Source_Ptr; begin -- A static constraint error in an instance body is not a fatal error. -- we choose to inhibit the message altogether, because there is no -- obvious node (for now) on which to post it. On the other hand the -- offending node must be replaced with a constraint_error in any case. -- No messages are generated if we already posted an error on this node if not Error_Posted (N) then if Loc /= No_Location then Eloc := Loc; else Eloc := Sloc (N); end if; -- Make all such messages unconditional Msgc (1 .. Msg'Length) := Msg; Msgc (Msg'Length + 1) := '!'; Msgl := Msg'Length + 1; -- Message is a warning, even in Ada 95 case if Msg (Msg'Length) = '?' then Wmsg := True; -- In Ada 83, all messages are warnings. In the private part and -- the body of an instance, constraint_checks are only warnings. -- We also make this a warning if the Warn parameter is set. elsif Warn or else (Ada_Version = Ada_83 and then Comes_From_Source (N)) then Msgl := Msgl + 1; Msgc (Msgl) := '?'; Wmsg := True; elsif In_Instance_Not_Visible then Msgl := Msgl + 1; Msgc (Msgl) := '?'; Wmsg := True; -- Otherwise we have a real error message (Ada 95 static case) else Wmsg := False; 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. Msgs := True; P := N; loop 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)))) then Msgs := False; exit; elsif Nkind (P) = N_Component_Association and then Nkind (Parent (P)) = N_Aggregate then null; -- Keep going. else exit when Nkind (P) not in N_Subexpr; end if; end loop; if Msgs then if Present (Ent) then Error_Msg_NEL (Msgc (1 .. Msgl), N, Ent, Eloc); else Error_Msg_NEL (Msgc (1 .. Msgl), N, Etype (N), Eloc); end if; if Wmsg then if Inside_Init_Proc then Error_Msg_NEL ("\& will be raised for objects of this type!?", N, Standard_Constraint_Error, Eloc); else Error_Msg_NEL ("\& 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); end if; end if; end if; return N; end Compile_Time_Constraint_Error; ----------------------- -- Conditional_Delay -- ----------------------- procedure Conditional_Delay (New_Ent, Old_Ent : Entity_Id) is begin if Has_Delayed_Freeze (Old_Ent) and then not Is_Frozen (Old_Ent) then Set_Has_Delayed_Freeze (New_Ent); end if; end Conditional_Delay; -------------------- -- Current_Entity -- -------------------- -- The currently visible definition for a given identifier is the -- one most chained at the start of the visibility chain, i.e. the -- one that is referenced by the Node_Id value of the name of the -- given identifier. function Current_Entity (N : Node_Id) return Entity_Id is begin return Get_Name_Entity_Id (Chars (N)); end Current_Entity; ----------------------------- -- Current_Entity_In_Scope -- ----------------------------- function Current_Entity_In_Scope (N : Node_Id) return Entity_Id is E : Entity_Id; CS : constant Entity_Id := Current_Scope; Transient_Case : constant Boolean := Scope_Is_Transient; 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)) loop E := Homonym (E); end loop; return E; end Current_Entity_In_Scope; ------------------- -- Current_Scope -- ------------------- function Current_Scope return Entity_Id is begin if Scope_Stack.Last = -1 then return Standard_Standard; else declare C : constant Entity_Id := Scope_Stack.Table (Scope_Stack.Last).Entity; begin if Present (C) then return C; else return Standard_Standard; end if; end; end if; end Current_Scope; ------------------------ -- Current_Subprogram -- ------------------------ 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; else return Enclosing_Subprogram (Scop); end if; end Current_Subprogram; --------------------- -- Defining_Entity -- --------------------- function Defining_Entity (N : Node_Id) return Entity_Id is K : constant Node_Kind := Nkind (N); Err : Entity_Id := Empty; begin case K is when N_Subprogram_Declaration | N_Abstract_Subprogram_Declaration | N_Subprogram_Body | N_Package_Declaration | N_Subprogram_Renaming_Declaration | N_Subprogram_Body_Stub | N_Generic_Subprogram_Declaration | N_Generic_Package_Declaration | N_Formal_Subprogram_Declaration => return Defining_Entity (Specification (N)); when N_Component_Declaration | N_Defining_Program_Unit_Name | N_Discriminant_Specification | N_Entry_Body | N_Entry_Declaration | N_Entry_Index_Specification | N_Exception_Declaration | N_Exception_Renaming_Declaration | N_Formal_Object_Declaration | N_Formal_Package_Declaration | N_Formal_Type_Declaration | N_Full_Type_Declaration | N_Implicit_Label_Declaration | N_Incomplete_Type_Declaration | N_Loop_Parameter_Specification | N_Number_Declaration | N_Object_Declaration | N_Object_Renaming_Declaration | N_Package_Body_Stub | N_Parameter_Specification | N_Private_Extension_Declaration | N_Private_Type_Declaration | N_Protected_Body | N_Protected_Body_Stub | N_Protected_Type_Declaration | N_Single_Protected_Declaration | N_Single_Task_Declaration | N_Subtype_Declaration | N_Task_Body | N_Task_Body_Stub | N_Task_Type_Declaration => return Defining_Identifier (N); when N_Subunit => return Defining_Entity (Proper_Body (N)); when N_Function_Instantiation | N_Function_Specification | N_Generic_Function_Renaming_Declaration | N_Generic_Package_Renaming_Declaration | N_Generic_Procedure_Renaming_Declaration | N_Package_Body | N_Package_Instantiation | N_Package_Renaming_Declaration | N_Package_Specification | N_Procedure_Instantiation | N_Procedure_Specification => declare Nam : constant Node_Id := Defining_Unit_Name (N); begin if Nkind (Nam) in N_Entity then return Nam; -- For Error, make up a name and attach to declaration -- so we can continue semantic analysis elsif Nam = Error then Err := Make_Defining_Identifier (Sloc (N), Chars => New_Internal_Name ('T')); Set_Defining_Unit_Name (N, Err); return Err; -- If not an entity, get defining identifier else return Defining_Identifier (Nam); end if; end; when N_Block_Statement => return Entity (Identifier (N)); when others => raise Program_Error; end case; end Defining_Entity; -------------------------- -- Denotes_Discriminant -- -------------------------- function Denotes_Discriminant (N : Node_Id; Check_Protected : Boolean := False) return Boolean is E : Entity_Id; begin if not Is_Entity_Name (N) or else No (Entity (N)) then return False; else E := Entity (N); end if; -- If we are checking for a protected type, the discriminant may have -- been rewritten as the corresponding discriminal of the original type -- or of the corresponding concurrent record, depending on whether we -- are in the spec or body of the protected type. return Ekind (E) = E_Discriminant or else (Check_Protected and then Ekind (E) = E_In_Parameter and then Present (Discriminal_Link (E)) and then (Is_Protected_Type (Scope (Discriminal_Link (E))) or else Is_Concurrent_Record_Type (Scope (Discriminal_Link (E))))); end Denotes_Discriminant; ----------------------------- -- Depends_On_Discriminant -- ----------------------------- function Depends_On_Discriminant (N : Node_Id) return Boolean is L : Node_Id; H : Node_Id; begin Get_Index_Bounds (N, L, H); return Denotes_Discriminant (L) or else Denotes_Discriminant (H); end Depends_On_Discriminant; ------------------------- -- Designate_Same_Unit -- ------------------------- function Designate_Same_Unit (Name1 : Node_Id; Name2 : Node_Id) return Boolean is K1 : constant Node_Kind := Nkind (Name1); K2 : constant Node_Kind := Nkind (Name2); function Prefix_Node (N : Node_Id) return Node_Id; -- Returns the parent unit name node of a defining program unit name -- or the prefix if N is a selected component or an expanded name. function Select_Node (N : Node_Id) return Node_Id; -- Returns the defining identifier node of a defining program unit -- name or the selector node if N is a selected component or an -- expanded name. ----------------- -- Prefix_Node -- ----------------- function Prefix_Node (N : Node_Id) return Node_Id is begin if Nkind (N) = N_Defining_Program_Unit_Name then return Name (N); else return Prefix (N); end if; end Prefix_Node; ----------------- -- Select_Node -- ----------------- function Select_Node (N : Node_Id) return Node_Id is begin if Nkind (N) = N_Defining_Program_Unit_Name then return Defining_Identifier (N); else return Selector_Name (N); end if; end Select_Node; -- Start of processing for Designate_Next_Unit begin if (K1 = N_Identifier or else K1 = N_Defining_Identifier) and then (K2 = N_Identifier or else K2 = N_Defining_Identifier) then return Chars (Name1) = Chars (Name2); elsif (K1 = N_Expanded_Name or else K1 = N_Selected_Component or else K1 = N_Defining_Program_Unit_Name) and then (K2 = N_Expanded_Name or else K2 = N_Selected_Component or else K2 = N_Defining_Program_Unit_Name) then return (Chars (Select_Node (Name1)) = Chars (Select_Node (Name2))) and then Designate_Same_Unit (Prefix_Node (Name1), Prefix_Node (Name2)); else return False; end if; end Designate_Same_Unit; ---------------------------- -- Enclosing_Generic_Body -- ---------------------------- function Enclosing_Generic_Body (E : Entity_Id) return Node_Id is P : Node_Id; Decl : Node_Id; Spec : Node_Id; begin P := Parent (E); while Present (P) loop if 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 P; end if; end if; end if; P := Parent (P); end loop; return Empty; end Enclosing_Generic_Body; ------------------------------- -- Enclosing_Lib_Unit_Entity -- ------------------------------- function Enclosing_Lib_Unit_Entity return Entity_Id is Unit_Entity : Entity_Id := Current_Scope; begin -- Look for enclosing library unit entity by following scope links. -- Equivalent to, but faster than indexing through the scope stack. while (Present (Scope (Unit_Entity)) and then Scope (Unit_Entity) /= Standard_Standard) and not Is_Child_Unit (Unit_Entity) loop Unit_Entity := Scope (Unit_Entity); end loop; return Unit_Entity; end Enclosing_Lib_Unit_Entity; ----------------------------- -- Enclosing_Lib_Unit_Node -- ----------------------------- function Enclosing_Lib_Unit_Node (N : Node_Id) return Node_Id is Current_Node : Node_Id := N; begin while Present (Current_Node) and then Nkind (Current_Node) /= N_Compilation_Unit loop Current_Node := Parent (Current_Node); end loop; if Nkind (Current_Node) /= N_Compilation_Unit then return Empty; end if; return Current_Node; end Enclosing_Lib_Unit_Node; -------------------------- -- Enclosing_Subprogram -- -------------------------- function Enclosing_Subprogram (E : Entity_Id) return Entity_Id is Dynamic_Scope : constant Entity_Id := Enclosing_Dynamic_Scope (E); begin if Dynamic_Scope = Standard_Standard 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 return Enclosing_Subprogram (Dynamic_Scope); elsif Ekind (Dynamic_Scope) = E_Task_Type then return Get_Task_Body_Procedure (Dynamic_Scope); elsif Convention (Dynamic_Scope) = Convention_Protected then return Protected_Body_Subprogram (Dynamic_Scope); else return Dynamic_Scope; end if; end Enclosing_Subprogram; ------------------------ -- Ensure_Freeze_Node -- ------------------------ procedure Ensure_Freeze_Node (E : Entity_Id) is FN : Node_Id; begin if No (Freeze_Node (E)) then FN := Make_Freeze_Entity (Sloc (E)); Set_Has_Delayed_Freeze (E); Set_Freeze_Node (E, FN); Set_Access_Types_To_Process (FN, No_Elist); Set_TSS_Elist (FN, No_Elist); Set_Entity (FN, E); end if; end Ensure_Freeze_Node; ---------------- -- Enter_Name -- ---------------- procedure Enter_Name (Def_Id : Node_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; function Is_Private_Component_Renaming (N : Node_Id) return Boolean; -- Recognize a renaming declaration that is introduced for private -- components of a protected type. We treat these as weak declarations -- so that they are overridden by entities with the same name that -- come from source, such as formals or local variables of a given -- protected declaration. ----------------------------------- -- Is_Private_Component_Renaming -- ----------------------------------- function Is_Private_Component_Renaming (N : Node_Id) return Boolean is begin return not Comes_From_Source (N) and then not Comes_From_Source (Current_Scope) and then Nkind (N) = N_Object_Renaming_Declaration; end Is_Private_Component_Renaming; -- Start of processing for Enter_Name begin Generate_Definition (Def_Id); -- Add new name to current scope declarations. Check for duplicate -- declaration, which may or may not be a genuine error. if Present (E) then -- Case of previous entity entered because of a missing declaration -- or else a bad subtype indication. Best is to use the new entity, -- and make the previous one invisible. if Etype (E) = Any_Type then Set_Is_Immediately_Visible (E, False); -- Case of renaming declaration constructed for package instances. -- if there is an explicit declaration with the same identifier, -- the renaming is not immediately visible any longer, but remains -- visible through selected component notation. elsif Nkind (Parent (E)) = N_Package_Renaming_Declaration and then not Comes_From_Source (E) then Set_Is_Immediately_Visible (E, False); -- The new entity may be the package renaming, which has the same -- same name as a generic formal which has been seen already. elsif Nkind (Parent (Def_Id)) = N_Package_Renaming_Declaration and then not Comes_From_Source (Def_Id) then Set_Is_Immediately_Visible (E, False); -- For a fat pointer corresponding to a remote access to subprogram, -- we use the same identifier as the RAS type, so that the proper -- name appears in the stub. This type is only retrieved through -- the RAS type and never by visibility, and is not added to the -- visibility list (see below). elsif Nkind (Parent (Def_Id)) = N_Full_Type_Declaration and then Present (Corresponding_Remote_Type (Def_Id)) then null; -- A controller component for a type extension overrides the -- inherited component. elsif Chars (E) = Name_uController then null; -- Case of an implicit operation or derived literal. The new entity -- hides the implicit one, which is removed from all visibility, -- i.e. the entity list of its scope, and homonym chain of its name. elsif (Is_Overloadable (E) and then Is_Inherited_Operation (E)) or else Is_Internal (E) then declare Prev : Entity_Id; Prev_Vis : Entity_Id; Decl : constant Node_Id := Parent (E); begin -- If E is an implicit declaration, it cannot be the first -- entity in the scope. Prev := First_Entity (Current_Scope); while Present (Prev) and then Next_Entity (Prev) /= E loop Next_Entity (Prev); end loop; if No (Prev) then -- If E is not on the entity chain of the current scope, -- it is an implicit declaration in the generic formal -- part of a generic subprogram. When analyzing the body, -- the generic formals are visible but not on the entity -- chain of the subprogram. The new entity will become -- the visible one in the body. pragma Assert (Nkind (Parent (Decl)) = N_Generic_Subprogram_Declaration); null; else Set_Next_Entity (Prev, Next_Entity (E)); if No (Next_Entity (Prev)) then Set_Last_Entity (Current_Scope, Prev); end if; if E = Current_Entity (E) then Prev_Vis := Empty; else Prev_Vis := Current_Entity (E); while Homonym (Prev_Vis) /= E loop Prev_Vis := Homonym (Prev_Vis); end loop; end if; if Present (Prev_Vis) then -- Skip E in the visibility chain Set_Homonym (Prev_Vis, Homonym (E)); else Set_Name_Entity_Id (Chars (E), Homonym (E)); end if; end if; end; -- This section of code could use a comment ??? elsif Present (Etype (E)) and then Is_Concurrent_Type (Etype (E)) and then E = Def_Id then return; elsif Is_Private_Component_Renaming (Parent (Def_Id)) then 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 null; -- When compiling a package body, some child units may have become -- visible. They cannot conflict with local entities that hide them. elsif Is_Child_Unit (E) and then In_Open_Scopes (Scope (E)) and then not Is_Immediately_Visible (E) then null; -- Conversely, with front-end inlining we may compile the parent -- body first, and a child unit subsequently. The context is now -- the parent spec, and body entities are not visible. elsif Is_Child_Unit (Def_Id) and then Is_Package_Body_Entity (E) and then not In_Package_Body (Current_Scope) then null; -- Case of genuine duplicate declaration else Error_Msg_Sloc := Sloc (E); -- If the previous declaration is an incomplete type declaration -- this may be an attempt to complete it with a private type. -- The following avoids confusing cascaded errors. if Nkind (Parent (E)) = N_Incomplete_Type_Declaration 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)); Set_Is_Immediately_Visible (E, False); Set_Full_View (E, Def_Id); 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; -- If the name of the unit appears in its own context clause, -- a dummy package with the name has already been created, and -- the error emitted. Try to continue quietly. elsif Error_Posted (E) and then Sloc (E) = No_Location and then Nkind (Parent (E)) = N_Package_Specification and then Current_Scope = Standard_Standard then Set_Scope (Def_Id, Current_Scope); return; else Error_Msg_N ("& conflicts with declaration#", Def_Id); -- Avoid cascaded messages with duplicate components in -- derived types. if Ekind (E) = E_Component or else Ekind (E) = E_Discriminant then return; end if; end if; if Nkind (Parent (Parent (Def_Id))) = N_Generic_Subprogram_Declaration and then Def_Id = Defining_Entity (Specification (Parent (Parent (Def_Id)))) then Error_Msg_N ("\generic units cannot be overloaded", Def_Id); end if; -- If entity is in standard, then we are in trouble, because -- it means that we have a library package with a duplicated -- name. That's hard to recover from, so abort! if S = Standard_Standard then raise Unrecoverable_Error; -- Otherwise we continue with the declaration. Having two -- identical declarations should not cause us too much trouble! else null; end if; end if; end if; -- If we fall through, declaration is OK , or OK enough to continue -- If Def_Id is a discriminant or a record component we are in the -- midst of inheriting components in a derived record definition. -- Preserve their Ekind and Etype. if Ekind (Def_Id) = E_Discriminant or else Ekind (Def_Id) = E_Component then null; -- If a type is already set, leave it alone (happens whey a type -- declaration is reanalyzed following a call to the optimizer) elsif Present (Etype (Def_Id)) then null; -- Otherwise, the kind E_Void insures that premature uses of the entity -- will be detected. Any_Type insures that no cascaded errors will occur else Set_Ekind (Def_Id, E_Void); Set_Etype (Def_Id, Any_Type); end if; -- Inherited discriminants and components in derived record types are -- immediately visible. Itypes are not. if Ekind (Def_Id) = E_Discriminant or else Ekind (Def_Id) = E_Component or else (No (Corresponding_Remote_Type (Def_Id)) and then not Is_Itype (Def_Id)) then Set_Is_Immediately_Visible (Def_Id); Set_Current_Entity (Def_Id); end if; Set_Homonym (Def_Id, C); Append_Entity (Def_Id, S); Set_Public_Status (Def_Id); -- 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) then Error_Msg_Sloc := Sloc (C); Error_Msg_N ("declaration hides &#?", Def_Id); end if; end Enter_Name; -------------------------- -- Explain_Limited_Type -- -------------------------- procedure Explain_Limited_Type (T : Entity_Id; N : Node_Id) is C : Entity_Id; begin -- For array, component type must be limited if Is_Array_Type (T) then Error_Msg_Node_2 := T; Error_Msg_NE ("component type& of type& is limited", N, Component_Type (T)); Explain_Limited_Type (Component_Type (T), N); elsif Is_Record_Type (T) then -- No need for extra messages if explicit limited record if Is_Limited_Record (Base_Type (T)) then return; end if; -- Otherwise find a limited component. Check only components that -- come from source, or inherited components that appear in the -- source of the ancestor. C := First_Component (T); while Present (C) loop if Is_Limited_Type (Etype (C)) and then (Comes_From_Source (C) or else (Present (Original_Record_Component (C)) and then Comes_From_Source (Original_Record_Component (C)))) then Error_Msg_Node_2 := T; Error_Msg_NE ("\component& of type& has limited type", N, C); Explain_Limited_Type (Etype (C), N); return; end if; Next_Component (C); end loop; -- The type may be declared explicitly limited, even if no component -- of it is limited, in which case we fall out of the loop. return; end if; end Explain_Limited_Type; ------------------------------------- -- Find_Corresponding_Discriminant -- ------------------------------------- function Find_Corresponding_Discriminant (Id : Node_Id; Typ : Entity_Id) return Entity_Id is Par_Disc : Entity_Id; Old_Disc : Entity_Id; New_Disc : Entity_Id; begin Par_Disc := Original_Record_Component (Original_Discriminant (Id)); -- The original type may currently be private, and the discriminant -- only appear on its full view. if Is_Private_Type (Scope (Par_Disc)) and then not Has_Discriminants (Scope (Par_Disc)) and then Present (Full_View (Scope (Par_Disc))) then Old_Disc := First_Discriminant (Full_View (Scope (Par_Disc))); else Old_Disc := First_Discriminant (Scope (Par_Disc)); end if; if Is_Class_Wide_Type (Typ) then New_Disc := First_Discriminant (Root_Type (Typ)); else New_Disc := First_Discriminant (Typ); end if; while Present (Old_Disc) and then Present (New_Disc) loop if Old_Disc = Par_Disc then return New_Disc; else Next_Discriminant (Old_Disc); Next_Discriminant (New_Disc); end if; end loop; -- Should always find it raise Program_Error; end Find_Corresponding_Discriminant; ----------------------------- -- Find_Static_Alternative -- ----------------------------- function Find_Static_Alternative (N : Node_Id) return Node_Id is Expr : constant Node_Id := Expression (N); Val : constant Uint := Expr_Value (Expr); Alt : Node_Id; Choice : Node_Id; begin Alt := First (Alternatives (N)); Search : loop if Nkind (Alt) /= N_Pragma then Choice := First (Discrete_Choices (Alt)); while Present (Choice) loop -- Others choice, always matches if Nkind (Choice) = N_Others_Choice then exit Search; -- Range, check if value is in the range elsif Nkind (Choice) = N_Range then exit Search when Val >= Expr_Value (Low_Bound (Choice)) and then Val <= Expr_Value (High_Bound (Choice)); -- Choice is a subtype name. Note that we know it must -- be a static subtype, since otherwise it would have -- been diagnosed as illegal. elsif Is_Entity_Name (Choice) and then Is_Type (Entity (Choice)) then exit Search when Is_In_Range (Expr, Etype (Choice)); -- Choice is a subtype indication elsif Nkind (Choice) = N_Subtype_Indication then declare C : constant Node_Id := Constraint (Choice); R : constant Node_Id := Range_Expression (C); begin exit Search when Val >= Expr_Value (Low_Bound (R)) and then Val <= Expr_Value (High_Bound (R)); end; -- Choice is a simple expression else exit Search when Val = Expr_Value (Choice); end if; Next (Choice); end loop; end if; Next (Alt); pragma Assert (Present (Alt)); end loop Search; -- The above loop *must* terminate by finding a match, since -- we know the case statement is valid, and the value of the -- expression is known at compile time. When we fall out of -- the loop, Alt points to the alternative that we know will -- be selected at run time. return Alt; end Find_Static_Alternative; ------------------ -- First_Actual -- ------------------ function First_Actual (Node : Node_Id) return Node_Id is N : Node_Id; begin if No (Parameter_Associations (Node)) then return Empty; end if; N := First (Parameter_Associations (Node)); if Nkind (N) = N_Parameter_Association then return First_Named_Actual (Node); else return N; end if; end First_Actual; ------------------------- -- Full_Qualified_Name -- ------------------------- function Full_Qualified_Name (E : Entity_Id) return String_Id is Res : String_Id; pragma Warnings (Off, Res); function Internal_Full_Qualified_Name (E : Entity_Id) return String_Id; -- Compute recursively the qualified name without NUL at the end ---------------------------------- -- Internal_Full_Qualified_Name -- ---------------------------------- function Internal_Full_Qualified_Name (E : Entity_Id) return String_Id is Ent : Entity_Id := E; Parent_Name : String_Id := No_String; begin -- Deals properly with child units if Nkind (Ent) = N_Defining_Program_Unit_Name then Ent := Defining_Identifier (Ent); end if; -- Compute recursively the qualification. Only "Standard" has no -- scope. if Present (Scope (Scope (Ent))) then Parent_Name := Internal_Full_Qualified_Name (Scope (Ent)); end if; -- Every entity should have a name except some expanded blocks -- don't bother about those. if Chars (Ent) = No_Name then return Parent_Name; end if; -- Add a period between Name and qualification if Parent_Name /= No_String then Start_String (Parent_Name); Store_String_Char (Get_Char_Code ('.')); else Start_String; end if; -- Generates the entity name in upper case Get_Name_String (Chars (Ent)); Set_All_Upper_Case; Store_String_Chars (Name_Buffer (1 .. Name_Len)); return End_String; end Internal_Full_Qualified_Name; -- Start of processing for Full_Qualified_Name begin Res := Internal_Full_Qualified_Name (E); Store_String_Char (Get_Char_Code (ASCII.nul)); return End_String; end Full_Qualified_Name; ----------------------- -- Gather_Components -- ----------------------- procedure Gather_Components (Typ : Entity_Id; Comp_List : Node_Id; Governed_By : List_Id; Into : Elist_Id; Report_Errors : out Boolean) is Assoc : Node_Id; Variant : Node_Id; Discrete_Choice : Node_Id; Comp_Item : Node_Id; Discrim : Entity_Id; Discrim_Name : Node_Id; Discrim_Value : Node_Id; begin Report_Errors := False; if No (Comp_List) or else Null_Present (Comp_List) then return; elsif Present (Component_Items (Comp_List)) then Comp_Item := First (Component_Items (Comp_List)); else Comp_Item := Empty; end if; while Present (Comp_Item) loop -- 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 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); end loop; if No (Variant_Part (Comp_List)) then return; else Discrim_Name := Name (Variant_Part (Comp_List)); Variant := First_Non_Pragma (Variants (Variant_Part (Comp_List))); end if; -- Look for the discriminant that governs this variant part. -- The discriminant *must* be in the Governed_By List Assoc := First (Governed_By); Find_Constraint : loop Discrim := First (Choices (Assoc)); exit Find_Constraint when Chars (Discrim_Name) = Chars (Discrim) or else (Present (Corresponding_Discriminant (Entity (Discrim))) and then Chars (Corresponding_Discriminant (Entity (Discrim))) = Chars (Discrim_Name)) or else Chars (Original_Record_Component (Entity (Discrim))) = Chars (Discrim_Name); if No (Next (Assoc)) then if not Is_Constrained (Typ) 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 -- explicit constraint. Renamed discriminants are handled in -- the code above. -- If several parent discriminants are renamed by a single -- discriminant of the derived type, the call to obtain the -- Corresponding_Discriminant field only retrieves the last -- of them. We recover the constraint on the others from the -- Stored_Constraint as well. declare D : Entity_Id; C : Elmt_Id; begin D := First_Discriminant (Etype (Typ)); C := First_Elmt (Stored_Constraint (Typ)); 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. null; else Assoc := Make_Component_Association (Sloc (Typ), New_List (New_Occurrence_Of (D, Sloc (Typ))), Duplicate_Subexpr_No_Checks (Node (C))); end if; exit Find_Constraint; end if; D := Next_Discriminant (D); Next_Elmt (C); end loop; end; end if; end if; if No (Next (Assoc)) then Error_Msg_NE (" missing value for discriminant&", First (Governed_By), Discrim_Name); Report_Errors := True; return; end if; Next (Assoc); end loop Find_Constraint; Discrim_Value := Expression (Assoc); if not Is_OK_Static_Expression (Discrim_Value) then Error_Msg_FE ("value for discriminant & must be static!", Discrim_Value, Discrim); Why_Not_Static (Discrim_Value); Report_Errors := True; return; end if; Search_For_Discriminant_Value : declare Low : Node_Id; High : Node_Id; UI_High : Uint; UI_Low : Uint; UI_Discrim_Value : constant Uint := Expr_Value (Discrim_Value); begin Find_Discrete_Value : while Present (Variant) loop Discrete_Choice := First (Discrete_Choices (Variant)); while Present (Discrete_Choice) loop exit Find_Discrete_Value when Nkind (Discrete_Choice) = N_Others_Choice; Get_Index_Bounds (Discrete_Choice, Low, High); UI_Low := Expr_Value (Low); UI_High := Expr_Value (High); exit Find_Discrete_Value when UI_Low <= UI_Discrim_Value and then UI_High >= UI_Discrim_Value; Next (Discrete_Choice); end loop; Next_Non_Pragma (Variant); end loop Find_Discrete_Value; end Search_For_Discriminant_Value; if No (Variant) then Error_Msg_NE ("value of discriminant & is out of range", Discrim_Value, Discrim); Report_Errors := True; return; end if; -- If we have found the corresponding choice, recursively add its -- components to the Into list. Gather_Components (Empty, Component_List (Variant), Governed_By, Into, Report_Errors); end Gather_Components; ------------------------ -- Get_Actual_Subtype -- ------------------------ function Get_Actual_Subtype (N : Node_Id) return Entity_Id is Typ : constant Entity_Id := Etype (N); Utyp : Entity_Id := Underlying_Type (Typ); Decl : Node_Id; Atyp : Entity_Id; begin if not Present (Utyp) then Utyp := Typ; end if; -- If what we have is an identifier that references a subprogram -- formal, or a variable or constant object, then we get the actual -- subtype from the referenced entity if one has been built. if Nkind (N) = N_Identifier and then (Is_Formal (Entity (N)) or else Ekind (Entity (N)) = E_Constant or else Ekind (Entity (N)) = E_Variable) and then Present (Actual_Subtype (Entity (N))) then return Actual_Subtype (Entity (N)); -- Actual subtype of unchecked union is always itself. We never need -- the "real" actual subtype. If we did, we couldn't get it anyway -- because the discriminant is not available. The restrictions on -- Unchecked_Union are designed to make sure that this is OK. elsif Is_Unchecked_Union (Base_Type (Utyp)) then return Typ; -- Here for the unconstrained case, we must find actual subtype -- No actual subtype is available, so we must build it on the fly. -- Checking the type, not the underlying type, for constrainedness -- seems to be necessary. Maybe all the tests should be on the type??? elsif (not Is_Constrained (Typ)) and then (Is_Array_Type (Utyp) or else (Is_Record_Type (Utyp) and then Has_Discriminants (Utyp))) and then not Has_Unknown_Discriminants (Utyp) and then not (Ekind (Utyp) = E_String_Literal_Subtype) then -- Nothing to do if in default expression if In_Default_Expression then return Typ; elsif Is_Private_Type (Typ) and then not Has_Discriminants (Typ) then -- If the type has no discriminants, there is no subtype to -- build, even if the underlying type is discriminated. return Typ; -- Else build the actual subtype else Decl := Build_Actual_Subtype (Typ, N); Atyp := Defining_Identifier (Decl); -- If Build_Actual_Subtype generated a new declaration then use it if Atyp /= Typ then -- The actual subtype is an Itype, so analyze the declaration, -- but do not attach it to the tree, to get the type defined. Set_Parent (Decl, N); Set_Is_Itype (Atyp); Analyze (Decl, Suppress => All_Checks); Set_Associated_Node_For_Itype (Atyp, N); Set_Has_Delayed_Freeze (Atyp, False); -- We need to freeze the actual subtype immediately. This is -- needed, because otherwise this Itype will not get frozen -- at all, and it is always safe to freeze on creation because -- any associated types must be frozen at this point. Freeze_Itype (Atyp, N); return Atyp; -- Otherwise we did not build a declaration, so return original else return Typ; end if; end if; -- For all remaining cases, the actual subtype is the same as -- the nominal type. else return Typ; end if; end Get_Actual_Subtype; ------------------------------------- -- Get_Actual_Subtype_If_Available -- ------------------------------------- function Get_Actual_Subtype_If_Available (N : Node_Id) return Entity_Id is Typ : constant Entity_Id := Etype (N); begin -- If what we have is an identifier that references a subprogram -- formal, or a variable or constant object, then we get the actual -- subtype from the referenced entity if one has been built. if Nkind (N) = N_Identifier and then (Is_Formal (Entity (N)) or else Ekind (Entity (N)) = E_Constant or else Ekind (Entity (N)) = E_Variable) and then Present (Actual_Subtype (Entity (N))) then return Actual_Subtype (Entity (N)); -- Otherwise the Etype of N is returned unchanged else return Typ; end if; end Get_Actual_Subtype_If_Available; ------------------------------- -- Get_Default_External_Name -- ------------------------------- function Get_Default_External_Name (E : Node_Or_Entity_Id) return Node_Id is begin Get_Decoded_Name_String (Chars (E)); if Opt.External_Name_Imp_Casing = Uppercase then Set_Casing (All_Upper_Case); else Set_Casing (All_Lower_Case); end if; return Make_String_Literal (Sloc (E), Strval => String_From_Name_Buffer); end Get_Default_External_Name; --------------------------- -- Get_Enum_Lit_From_Pos -- --------------------------- function Get_Enum_Lit_From_Pos (T : Entity_Id; Pos : Uint; Loc : Source_Ptr) return Node_Id is Lit : Node_Id; begin -- In the case where the literal is of type Character, Wide_Character -- or Wide_Wide_Character or of a type derived from them, there needs -- to be some special handling since there is no explicit chain of -- 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 Set_Character_Literal_Name (UI_To_CC (Pos)); return Make_Character_Literal (Loc, Chars => Name_Find, Char_Literal_Value => Pos); -- For all other cases, we have a complete table of literals, and -- we simply iterate through the chain of literal until the one -- with the desired position value is found. -- else Lit := First_Literal (Base_Type (T)); for J in 1 .. UI_To_Int (Pos) loop Next_Literal (Lit); end loop; return New_Occurrence_Of (Lit, Loc); end if; end Get_Enum_Lit_From_Pos; ------------------------ -- Get_Generic_Entity -- ------------------------ function Get_Generic_Entity (N : Node_Id) return Entity_Id is Ent : constant Entity_Id := Entity (Name (N)); begin if Present (Renamed_Object (Ent)) then return Renamed_Object (Ent); else return Ent; end if; end Get_Generic_Entity; ---------------------- -- Get_Index_Bounds -- ---------------------- procedure Get_Index_Bounds (N : Node_Id; L, H : out Node_Id) is Kind : constant Node_Kind := Nkind (N); R : Node_Id; begin if Kind = N_Range then L := Low_Bound (N); H := High_Bound (N); elsif Kind = N_Subtype_Indication then R := Range_Expression (Constraint (N)); if R = Error then L := Error; H := Error; return; else L := Low_Bound (Range_Expression (Constraint (N))); H := High_Bound (Range_Expression (Constraint (N))); end if; elsif Is_Entity_Name (N) and then Is_Type (Entity (N)) then if Error_Posted (Scalar_Range (Entity (N))) then L := Error; H := Error; elsif Nkind (Scalar_Range (Entity (N))) = N_Subtype_Indication then Get_Index_Bounds (Scalar_Range (Entity (N)), L, H); else L := Low_Bound (Scalar_Range (Entity (N))); H := High_Bound (Scalar_Range (Entity (N))); end if; else -- N is an expression, indicating a range with one value L := N; H := N; end if; end Get_Index_Bounds; ---------------------------------- -- Get_Library_Unit_Name_string -- ---------------------------------- procedure Get_Library_Unit_Name_String (Decl_Node : Node_Id) is Unit_Name_Id : constant Unit_Name_Type := Get_Unit_Name (Decl_Node); begin Get_Unit_Name_String (Unit_Name_Id); -- Remove seven last character (" (spec)" or " (body)") Name_Len := Name_Len - 7; pragma Assert (Name_Buffer (Name_Len + 1) = ' '); end Get_Library_Unit_Name_String; ------------------------ -- Get_Name_Entity_Id -- ------------------------ function Get_Name_Entity_Id (Id : Name_Id) return Entity_Id is begin return Entity_Id (Get_Name_Table_Info (Id)); end Get_Name_Entity_Id; --------------------------- -- Get_Referenced_Object -- --------------------------- function Get_Referenced_Object (N : Node_Id) return Node_Id is R : Node_Id := N; begin while Is_Entity_Name (R) and then Present (Renamed_Object (Entity (R))) loop R := Renamed_Object (Entity (R)); end loop; return R; end Get_Referenced_Object; ------------------------- -- Get_Subprogram_Body -- ------------------------- function Get_Subprogram_Body (E : Entity_Id) return Node_Id is Decl : Node_Id; begin Decl := Unit_Declaration_Node (E); if Nkind (Decl) = N_Subprogram_Body then return Decl; -- The below comment is bad, because it is possible for -- Nkind (Decl) to be an N_Subprogram_Body_Stub ??? else -- Nkind (Decl) = N_Subprogram_Declaration if Present (Corresponding_Body (Decl)) then return Unit_Declaration_Node (Corresponding_Body (Decl)); -- Imported subprogram case else return Empty; end if; end if; end Get_Subprogram_Body; ----------------------------- -- Get_Task_Body_Procedure -- ----------------------------- 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 -- 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. return Task_Body_Procedure (Underlying_Type (Root_Type (E))); end Get_Task_Body_Procedure; ----------------------- -- Has_Access_Values -- ----------------------- function Has_Access_Values (T : Entity_Id) return Boolean is Typ : constant Entity_Id := Underlying_Type (T); begin -- Case of a private type which is not completed yet. This can only -- happen in the case of a generic format type appearing directly, or -- as a component of the type to which this function is being applied -- at the top level. Return False in this case, since we certainly do -- not know that the type contains access types. if No (Typ) then return False; elsif Is_Access_Type (Typ) then return True; elsif Is_Array_Type (Typ) then return Has_Access_Values (Component_Type (Typ)); elsif Is_Record_Type (Typ) then declare Comp : Entity_Id; begin Comp := First_Entity (Typ); while Present (Comp) loop if (Ekind (Comp) = E_Component or else Ekind (Comp) = E_Discriminant) and then Has_Access_Values (Etype (Comp)) then return True; end if; Next_Entity (Comp); end loop; end; return False; else return False; end if; end Has_Access_Values; ---------------------- -- Has_Declarations -- ---------------------- function Has_Declarations (N : Node_Id) return Boolean is K : constant Node_Kind := Nkind (N); begin return K = N_Accept_Statement or else K = N_Block_Statement or else K = N_Compilation_Unit_Aux or else K = N_Entry_Body or else K = N_Package_Body or else K = N_Protected_Body or else K = N_Subprogram_Body or else K = N_Task_Body or else K = N_Package_Specification; end Has_Declarations; ------------------------------------------- -- Has_Discriminant_Dependent_Constraint -- ------------------------------------------- function Has_Discriminant_Dependent_Constraint (Comp : Entity_Id) return Boolean is Comp_Decl : constant Node_Id := Parent (Comp); Subt_Indic : constant Node_Id := Subtype_Indication (Component_Definition (Comp_Decl)); Constr : Node_Id; Assn : Node_Id; begin if Nkind (Subt_Indic) = N_Subtype_Indication then Constr := Constraint (Subt_Indic); if Nkind (Constr) = N_Index_Or_Discriminant_Constraint then Assn := First (Constraints (Constr)); while Present (Assn) loop case Nkind (Assn) is when N_Subtype_Indication | N_Range | N_Identifier => if Depends_On_Discriminant (Assn) then return True; end if; when N_Discriminant_Association => if Depends_On_Discriminant (Expression (Assn)) then return True; end if; when others => null; end case; Next (Assn); end loop; end if; end if; return False; end Has_Discriminant_Dependent_Constraint; -------------------- -- Has_Infinities -- -------------------- function Has_Infinities (E : Entity_Id) return Boolean is begin return Is_Floating_Point_Type (E) and then Nkind (Scalar_Range (E)) = N_Range and then Includes_Infinities (Scalar_Range (E)); end Has_Infinities; ------------------------ -- 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 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; else return False; end if; end Has_Null_Extension; --------------------------- -- Has_Private_Component -- --------------------------- function Has_Private_Component (Type_Id : Entity_Id) return Boolean is Btype : Entity_Id := Base_Type (Type_Id); Component : Entity_Id; begin if Error_Posted (Type_Id) or else Error_Posted (Btype) then return False; end if; if Is_Class_Wide_Type (Btype) then Btype := Root_Type (Btype); end if; 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 Is_Array_Type (Btype) then return Has_Private_Component (Component_Type (Btype)); 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; Next_Component (Component); end loop; return False; elsif Is_Protected_Type (Btype) and then Present (Corresponding_Record_Type (Btype)) then return Has_Private_Component (Corresponding_Record_Type (Btype)); else return False; end if; end Has_Private_Component; ---------------- -- Has_Stream -- ---------------- function Has_Stream (T : Entity_Id) return Boolean is E : Entity_Id; begin if No (T) then return False; elsif Is_RTE (Root_Type (T), RE_Root_Stream_Type) then return True; elsif Is_Array_Type (T) then return Has_Stream (Component_Type (T)); 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; return False; elsif Is_Private_Type (T) then return Has_Stream (Underlying_Type (T)); else return False; end if; end Has_Stream; -------------------------- -- Has_Tagged_Component -- -------------------------- function Has_Tagged_Component (Typ : Entity_Id) return Boolean is Comp : Entity_Id; begin if Is_Private_Type (Typ) and then Present (Underlying_Type (Typ)) then return Has_Tagged_Component (Underlying_Type (Typ)); elsif Is_Array_Type (Typ) then return Has_Tagged_Component (Component_Type (Typ)); 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; Comp := Next_Component (Typ); end loop; return False; else return False; end if; end Has_Tagged_Component; ----------------- -- In_Instance -- ----------------- function In_Instance return Boolean is S : Entity_Id := Current_Scope; 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; S := Scope (S); end loop; return False; end In_Instance; ---------------------- -- In_Instance_Body -- ---------------------- function In_Instance_Body return Boolean is S : Entity_Id := Current_Scope; 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 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 := Current_Scope; 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 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 := Current_Scope; 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; S := Scope (S); end loop; return False; end In_Instance_Visible_Part; ---------------------- -- In_Packiage_Body -- ---------------------- function In_Package_Body return Boolean is S : Entity_Id := Current_Scope; 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; return False; end In_Package_Body; -------------------------------------- -- 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; ------------------- -- Is_AAMP_Float -- ------------------- function Is_AAMP_Float (E : Entity_Id) return Boolean is begin pragma Assert (Is_Type (E)); 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 ((Ekind (E) = E_Task_Type or else Ekind (E) = E_Protected_Type) and then In_Open_Scopes (E)) -- Current instance of type 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 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; 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_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: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. if Is_Access_Type (Prefix_Type) and then not Has_Constrained_Partial_View (Designated_Type (Prefix_Type)) then return False; elsif Nkind (P) = N_Explicit_Dereference and then not Has_Constrained_Partial_View (Prefix_Type) then return False; 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. 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 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; raise Program_Error; end Is_Descendent_Of; ------------------------------ -- Is_Descendent_Of_Address -- ------------------------------ function Is_Descendent_Of_Address (T1 : Entity_Id) return Boolean is begin -- If Address has not been loaded, answer must be False if not RTU_Loaded (System) then return False; -- Otherwise we can get the entity we are interested in without -- causing an unwanted dependency on System, and do the test. else return Is_Descendent_Of (T1, Base_Type (RTE (RE_Address))); end if; end Is_Descendent_Of_Address; -------------- -- 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) 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)) 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; 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 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. 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_Lvalue -- --------------- function Is_Lvalue (N : Node_Id) return Boolean is P : constant Node_Id := Parent (N); begin case Nkind (P) is -- Test left side of assignment when N_Assignment_Statement => return N = Name (P); -- Test prefix of component or attribute when N_Attribute_Reference | N_Expanded_Name | N_Explicit_Dereference | N_Indexed_Component | N_Reference | N_Selected_Component | N_Slice => return N = Prefix (P); -- Test subprogram parameter (we really should check the -- parameter mode, but it is not worth the trouble) when N_Function_Call | N_Procedure_Call_Statement | N_Accept_Statement | N_Parameter_Association => return True; -- Test for appearing in a conversion that itself appears -- in an lvalue context, since this should be an lvalue. when N_Type_Conversion => return Is_Lvalue (P); -- Test for appearence in object renaming declaration when N_Object_Renaming_Declaration => return True; -- All other references are definitely not Lvalues when others => return False; end case; end Is_Lvalue; ------------------------- -- Is_Object_Reference -- ------------------------- function Is_Object_Reference (N : Node_Id) return Boolean is begin if Is_Entity_Name (N) then return Is_Object (Entity (N)); 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))); -- In Ada95, a function call is a constant object; a procedure -- call is not. when N_Function_Call => return Etype (N) /= Standard_Void_Type; -- A reference to the stream attribute Input is a function call when N_Attribute_Reference => return Attribute_Name (N) = Name_Input; 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)))); when N_Explicit_Dereference => return True; -- A view conversion of a tagged object is an object reference 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)); -- 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). when N_Unchecked_Type_Conversion => return True; when others => return False; end case; end if; end Is_Object_Reference; ----------------------------------- -- Is_OK_Variable_For_Out_Formal -- ----------------------------------- function Is_OK_Variable_For_Out_Formal (AV : Node_Id) return Boolean is begin Note_Possible_Modification (AV); -- 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 Paren_Count (AV) > 0 and then Comes_From_Source (AV) then return False; -- A variable is always allowed elsif Is_Variable (AV) then return True; -- 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. elsif Nkind (AV) = N_Unchecked_Type_Conversion then if Nkind (Original_Node (AV)) = N_Function_Call then return False; elsif Comes_From_Source (AV) and then Nkind (Original_Node (Expression (AV))) = N_Function_Call then return False; elsif Nkind (Original_Node (AV)) = N_Type_Conversion then return Is_OK_Variable_For_Out_Formal (Expression (AV)); else return True; end if; -- Normal type conversions are allowed if argument is a variable 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; -- We also allow a non-parenthesized expression that raises -- constraint error if it rewrites what used to be a variable 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; -- 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). elsif Original_Node (AV) /= AV then return Is_OK_Variable_For_Out_Formal (Original_Node (AV)); -- All other non-variables are rejected else return False; end if; end Is_OK_Variable_For_Out_Formal; ----------------------------------- -- Is_Partially_Initialized_Type -- ----------------------------------- function Is_Partially_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 component type is partially initialized, so is array type if Is_Partially_Initialized_Type (Component_Type (Typ)) then return True; -- 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; elsif Is_Record_Type (Typ) then -- A discriminated type is always partially initialized if Has_Discriminants (Typ) then return True; -- A tagged type is always partially initialized elsif Is_Tagged_Type (Typ) then return True; -- Case of non-discriminated record else declare 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 -- Loop through components Ent := First_Entity (Typ); while Present (Ent) loop if Ekind (Ent) = E_Component then Component_Present := True; -- 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; -- If a component is of a type which is itself partially -- initialized, then the enclosing record type is also. elsif Is_Partially_Initialized_Type (Etype (Ent)) then return True; end if; end if; Next_Entity (Ent); end loop; -- No initialized components found. If we found any components -- they were all uninitialized so the result is false. if Component_Present then return False; -- But if we found no components, then all the components are -- initialized so we consider the type to be initialized. else return True; end if; end; end if; -- 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 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 -- ------------------------------------ function Is_Potentially_Persistent_Type (T : Entity_Id) return Boolean is Comp : Entity_Id; Indx : Node_Id; begin -- For private type, test corrresponding full type if Is_Private_Type (T) then return Is_Potentially_Persistent_Type (Full_View (T)); -- Scalar types are potentially persistent elsif Is_Scalar_Type (T) then return True; -- 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. 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; return True; -- Array type is potentially persistent if its component type is -- potentially persistent and if all its constraints are static. 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 Next_Index (Indx); end if; end loop; return True; -- All other types are not potentially persistent else return False; 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 function Is_RCI_Pkg_Decl_Cunit (Cunit : Node_Id) return Boolean; -- Return True if the unit of Cunit is an RCI package declaration --------------------------- -- Is_RCI_Pkg_Decl_Cunit -- --------------------------- function Is_RCI_Pkg_Decl_Cunit (Cunit : Node_Id) return Boolean is The_Unit : constant Node_Id := Unit (Cunit); 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; -- Start of processing for Is_RCI_Pkg_Spec_Or_Body 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; ----------------------------------------- -- Is_Remote_Access_To_Class_Wide_Type -- ----------------------------------------- function Is_Remote_Access_To_Class_Wide_Type (E : Entity_Id) return Boolean is D : Entity_Id; 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. ------------------------------------------------- -- Comes_From_Limited_Private_Type_Declaration -- ------------------------------------------------- function Comes_From_Limited_Private_Type_Declaration (E : Entity_Id) return Boolean is N : constant Node_Id := Declaration_Node (E); begin if Nkind (N) = N_Private_Type_Declaration and then Limited_Present (N) 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; return False; end Comes_From_Limited_Private_Type_Declaration; -- Start of processing for Is_Remote_Access_To_Class_Wide_Type begin if not (Is_Remote_Call_Interface (E) or else Is_Remote_Types (E)) or else Ekind (E) /= E_General_Access_Type then return False; end if; D := Designated_Type (E); if Ekind (D) /= E_Class_Wide_Type then return False; end if; 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 -- ----------------------------------------- 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; -------------------- -- Is_Remote_Call -- -------------------- 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 return False; 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 return True; 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 return True; 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. return True; end if; -- All other calls are local calls return False; end Is_Remote_Call; ---------------------- -- Is_Renamed_Entry -- ---------------------- function Is_Renamed_Entry (Proc_Nam : Entity_Id) return Boolean is Orig_Node : Node_Id := Empty; Subp_Decl : Node_Id := Parent (Parent (Proc_Nam)); function Is_Entry (Nam : Node_Id) return Boolean; -- Determine whether Nam is an entry. Traverse selectors -- if there are nested selected components. -------------- -- 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 begin if Present (Alias (Proc_Nam)) then Subp_Decl := Parent (Parent (Alias (Proc_Nam))); end if; -- Look for a rewritten subprogram renaming declaration if Nkind (Subp_Decl) = N_Subprogram_Declaration and then Present (Original_Node (Subp_Decl)) then Orig_Node := Original_Node (Subp_Decl); end if; -- The rewritten subprogram is actually an entry 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; return False; end Is_Renamed_Entry; ---------------------- -- Is_Selector_Name -- ---------------------- 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; 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; ------------------ -- Is_Statement -- ------------------ 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; ----------------- -- Is_Transfer -- ----------------- function Is_Transfer (N : Node_Id) return Boolean is Kind : constant Node_Kind := Nkind (N); 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; elsif (Kind = N_Exit_Statement or else Kind in N_Raise_xxx_Error) and then No (Condition (N)) then return True; 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_Transfer; ------------- -- Is_True -- ------------- function Is_True (U : Uint) return Boolean is begin return (U /= 0); end Is_True; ----------------- -- Is_Variable -- ----------------- function Is_Variable (N : Node_Id) return Boolean is 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. 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. 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. --------------------------- -- In_Protected_Function -- --------------------------- 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 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; S := Scope (S); end loop; return False; end if; end In_Protected_Function; ------------------------ -- Is_Variable_Prefix -- ------------------------ 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))); -- 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. 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 return Is_Variable (P); end if; end Is_Variable_Prefix; -- Start of processing for Is_Variable 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 Nkind (N) in N_Subexpr and then Assignment_OK (N) then return True; -- 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). 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))); -- A function call is never a variable elsif Nkind (N) = N_Function_Call then return False; -- All remaining checks use the original node elsif Is_Entity_Name (Orig_Node) then declare E : constant Entity_Id := Entity (Orig_Node); K : constant Entity_Kind := Ekind (E); 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 -- Current instance of 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; else case Nkind (Orig_Node) is when N_Indexed_Component | N_Slice => return Is_Variable_Prefix (Prefix (Orig_Node)); when N_Selected_Component => return Is_Variable_Prefix (Prefix (Orig_Node)) and then Is_Variable (Selector_Name (Orig_Node)); -- For an explicit dereference, the type of the prefix cannot -- be an access to constant or an access to subprogram. 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; -- 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). 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))))); -- 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. when N_Unchecked_Type_Conversion => return Is_Variable (Expression (Orig_Node)); when others => return False; end case; end if; end Is_Variable; ------------------------ -- Is_Volatile_Object -- ------------------------ function Is_Volatile_Object (N : Node_Id) return Boolean is function Object_Has_Volatile_Components (N : Node_Id) return Boolean; -- Determines if given object has volatile components function Is_Volatile_Prefix (N : Node_Id) return Boolean; -- If prefix is an implicit dereference, examine designated type ------------------------ -- Is_Volatile_Prefix -- ------------------------ function Is_Volatile_Prefix (N : Node_Id) return Boolean is Typ : constant Entity_Id := Etype (N); begin if Is_Access_Type (Typ) then declare Dtyp : constant Entity_Id := Designated_Type (Typ); begin return Is_Volatile (Dtyp) or else Has_Volatile_Components (Dtyp); end; else return Object_Has_Volatile_Components (N); end if; end Is_Volatile_Prefix; ------------------------------------ -- Object_Has_Volatile_Components -- ------------------------------------ function Object_Has_Volatile_Components (N : Node_Id) return Boolean is Typ : constant Entity_Id := Etype (N); begin if Is_Volatile (Typ) or else Has_Volatile_Components (Typ) then return True; elsif Is_Entity_Name (N) and then (Has_Volatile_Components (Entity (N)) or else Is_Volatile (Entity (N))) then return True; 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_Volatile_Object begin if Is_Volatile (Etype (N)) or else (Is_Entity_Name (N) and then Is_Volatile (Entity (N))) then return True; 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 Is_Volatile_Object; ------------------------- -- Kill_Current_Values -- ------------------------- procedure Kill_Current_Values is S : Entity_Id; procedure Kill_Current_Values_For_Entity_Chain (E : Entity_Id); -- Clear current value for entity E and all entities chained to E ------------------------------------------ -- Kill_Current_Values_For_Entity_Chain -- ------------------------------------------ procedure Kill_Current_Values_For_Entity_Chain (E : Entity_Id) is Ent : Entity_Id; begin Ent := E; while Present (Ent) loop if Is_Object (Ent) then Set_Current_Value (Ent, Empty); if not Can_Never_Be_Null (Ent) then Set_Is_Known_Non_Null (Ent, False); end if; end if; Next_Entity (Ent); end loop; end Kill_Current_Values_For_Entity_Chain; -- Start of processing for Kill_Current_Values begin -- Kill all saved checks, a special case of killing saved values Kill_All_Checks; -- Loop through relevant scopes, which includes the current scope and -- any parent scopes if the current scope is a block or a package. S := Current_Scope; Scope_Loop : loop -- Clear current values of all entities in current scope Kill_Current_Values_For_Entity_Chain (First_Entity (S)); -- If scope is a package, also clear current values of all -- private entities in the scope. 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; -- If this is a block or nested package, deal with parent 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; -------------------------- -- 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 Kill_Size_Check_Code; ------------------------- -- New_External_Entity -- ------------------------- function New_External_Entity (Kind : Entity_Kind; Scope_Id : Entity_Id; Sloc_Value : Source_Ptr; Related_Id : Entity_Id; Suffix : Character; Suffix_Index : Nat := 0; Prefix : Character := ' ') return Entity_Id is N : constant Entity_Id := Make_Defining_Identifier (Sloc_Value, New_External_Name (Chars (Related_Id), Suffix, Suffix_Index, Prefix)); begin Set_Ekind (N, Kind); Set_Is_Internal (N, True); Append_Entity (N, Scope_Id); Set_Public_Status (N); if Kind in Type_Kind then Init_Size_Align (N); end if; return N; end New_External_Entity; ------------------------- -- New_Internal_Entity -- ------------------------- function New_Internal_Entity (Kind : Entity_Kind; Scope_Id : Entity_Id; Sloc_Value : Source_Ptr; Id_Char : Character) return Entity_Id is N : constant Entity_Id := Make_Defining_Identifier (Sloc_Value, New_Internal_Name (Id_Char)); begin Set_Ekind (N, Kind); Set_Is_Internal (N, True); Append_Entity (N, Scope_Id); if Kind in Type_Kind then Init_Size_Align (N); end if; return N; end New_Internal_Entity; ----------------- -- Next_Actual -- ----------------- function Next_Actual (Actual_Id : Node_Id) return Node_Id 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 Is_List_Member (Actual_Id) then N := Next (Actual_Id); if Nkind (N) = N_Parameter_Association then return First_Named_Actual (Parent (Actual_Id)); else return N; end if; else return Next_Named_Actual (Parent (Actual_Id)); end if; end Next_Actual; procedure Next_Actual (Actual_Id : in out Node_Id) is begin Actual_Id := Next_Actual (Actual_Id); end Next_Actual; ----------------------- -- 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. -- 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 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; S : Entity_Id; Report : Boolean; Success : out Boolean) is Actuals : constant List_Id := Parameter_Associations (N); Actual : Node_Id := Empty; Formal : Entity_Id; Last : Node_Id := Empty; First_Named : Node_Id := Empty; Found : Boolean; Formals_To_Match : Integer := 0; Actuals_To_Match : Integer := 0; procedure Chain (A : Node_Id); -- Add named actual at the proper place in the list, using the -- Next_Named_Actual link. function Reporting return Boolean; -- Determines if an error is to be reported. To report an error, we -- need Report to be True, and also we do not report errors caused -- by calls to init procs that occur within other init procs. Such -- errors must always be cascaded errors, since if all the types are -- declared correctly, the compiler will certainly build decent calls! ----------- -- Chain -- ----------- procedure Chain (A : Node_Id) is begin if No (Last) then -- Call node points to first actual in list Set_First_Named_Actual (N, Explicit_Actual_Parameter (A)); else Set_Next_Named_Actual (Last, Explicit_Actual_Parameter (A)); end if; Last := A; Set_Next_Named_Actual (Last, Empty); end Chain; --------------- -- Reporting -- --------------- function Reporting return Boolean is begin if not Report then return False; elsif not Within_Init_Proc then return True; elsif Is_Init_Proc (Entity (Name (N))) then return False; else return True; end if; end Reporting; -- Start of processing for Normalize_Actuals begin if Is_Access_Type (S) then -- The name in the call is a function call that returns an access -- to subprogram. The designated type has the list of formals. Formal := First_Formal (Designated_Type (S)); else Formal := First_Formal (S); end if; while Present (Formal) loop Formals_To_Match := Formals_To_Match + 1; Next_Formal (Formal); end loop; -- Find if there is a named association, and verify that no positional -- associations appear after named ones. if Present (Actuals) then Actual := First (Actuals); end if; while Present (Actual) and then Nkind (Actual) /= N_Parameter_Association loop Actuals_To_Match := Actuals_To_Match + 1; Next (Actual); end loop; if No (Actual) and Actuals_To_Match = Formals_To_Match then -- Most common case: positional notation, no defaults Success := True; return; elsif Actuals_To_Match > Formals_To_Match then -- Too many actuals: will not work if Reporting then if Is_Entity_Name (Name (N)) then Error_Msg_N ("too many arguments in call to&", Name (N)); else Error_Msg_N ("too many arguments in call", N); end if; end if; Success := False; return; end if; First_Named := Actual; while Present (Actual) loop if Nkind (Actual) /= N_Parameter_Association then Error_Msg_N ("positional parameters not allowed after named ones", Actual); Success := False; return; else Actuals_To_Match := Actuals_To_Match + 1; end if; Next (Actual); end loop; if Present (Actuals) then Actual := First (Actuals); end if; 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. if Present (Actual) and then Nkind (Actual) /= N_Parameter_Association then Next (Actual); Actuals_To_Match := Actuals_To_Match - 1; Formals_To_Match := Formals_To_Match - 1; else -- For named parameters, search the list of actuals to find -- one that matches the next formal name. Actual := First_Named; Found := False; while Present (Actual) loop if Chars (Selector_Name (Actual)) = Chars (Formal) then Found := True; Chain (Actual); Actuals_To_Match := Actuals_To_Match - 1; Formals_To_Match := Formals_To_Match - 1; exit; end if; Next (Actual); end loop; if not Found then if Ekind (Formal) /= E_In_Parameter or else No (Default_Value (Formal)) then if Reporting then if (Comes_From_Source (S) or else Sloc (S) = Standard_Location) and then Is_Overloadable (S) then if No (Actuals) and then (Nkind (Parent (N)) = N_Procedure_Call_Statement or else (Nkind (Parent (N)) = N_Function_Call or else Nkind (Parent (N)) = N_Parameter_Association)) and then Ekind (S) /= E_Function then Set_Etype (N, Etype (S)); else Error_Msg_Name_1 := Chars (S); Error_Msg_Sloc := Sloc (S); Error_Msg_NE ("missing argument for parameter & " & "in call to % declared #", N, Formal); end if; elsif Is_Overloadable (S) then Error_Msg_Name_1 := Chars (S); -- Point to type derivation that generated the -- operation. Error_Msg_Sloc := Sloc (Parent (S)); Error_Msg_NE ("missing argument for parameter & " & "in call to % (inherited) #", N, Formal); else Error_Msg_NE ("missing argument for parameter &", N, Formal); end if; end if; Success := False; return; else Formals_To_Match := Formals_To_Match - 1; end if; end if; end if; Next_Formal (Formal); end loop; if Formals_To_Match = 0 and then Actuals_To_Match = 0 then Success := True; return; else if Reporting then -- Find some superfluous named actual that did not get -- attached to the list of associations. Actual := First (Actuals); while Present (Actual) loop if Nkind (Actual) = N_Parameter_Association and then Actual /= Last and then No (Next_Named_Actual (Actual)) then Error_Msg_N ("unmatched actual & in call", Selector_Name (Actual)); exit; end if; Next (Actual); end loop; end if; Success := False; return; end if; end Normalize_Actuals; -------------------------------- -- Note_Possible_Modification -- -------------------------------- procedure Note_Possible_Modification (N : Node_Id) is Modification_Comes_From_Source : constant Boolean := Comes_From_Source (Parent (N)); Ent : Entity_Id; Exp : Node_Id; begin -- Loop to find referenced entity, if there is one Exp := N; loop <<Continue>> Ent := Empty; if Is_Entity_Name (Exp) then Ent := Entity (Exp); -- If the entity is missing, it is an undeclared identifier, -- and there is nothing to annotate. if No (Ent) then return; end if; elsif Nkind (Exp) = N_Explicit_Dereference then declare P : constant Node_Id := Prefix (Exp); begin if Nkind (P) = N_Selected_Component and then Present ( Entry_Formal (Entity (Selector_Name (P)))) then -- Case of a reference to an entry formal Ent := Entry_Formal (Entity (Selector_Name (P))); elsif Nkind (P) = N_Identifier and then Nkind (Parent (Entity (P))) = N_Object_Declaration and then Present (Expression (Parent (Entity (P)))) and then Nkind (Expression (Parent (Entity (P)))) = N_Reference then -- Case of a reference to a value on which -- side effects have been removed. Exp := Prefix (Expression (Parent (Entity (P)))); else return; end if; end; elsif Nkind (Exp) = N_Type_Conversion or else Nkind (Exp) = N_Unchecked_Type_Conversion then Exp := Expression (Exp); elsif Nkind (Exp) = N_Slice or else Nkind (Exp) = N_Indexed_Component or else Nkind (Exp) = N_Selected_Component then Exp := Prefix (Exp); 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 Set_Never_Set_In_Source (Ent, False); end if; Set_Is_True_Constant (Ent, False); Set_Current_Value (Ent, Empty); if not Can_Never_Be_Null (Ent) then Set_Is_Known_Non_Null (Ent, False); end if; if (Ekind (Ent) = E_Variable or else Ekind (Ent) = E_Constant) and then Present (Renamed_Object (Ent)) then Exp := Renamed_Object (Ent); goto Continue; end if; -- Generate a reference only if the assignment comes from -- source. This excludes, for example, calls to a dispatching -- assignment operation when the left-hand side is tagged. if Modification_Comes_From_Source then Generate_Reference (Ent, Exp, 'm'); end if; end if; Kill_Checks (Ent); return; end if; end loop; end Note_Possible_Modification; ------------------------- -- Object_Access_Level -- ------------------------- 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)). 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_Type (E) then return Type_Access_Level (E) + 1; elsif Present (Renamed_Object (E)) then return Object_Access_Level (Renamed_Object (E)); -- Similarly, if E is a component of the current instance of a -- protected type, any instance of it is assumed to be at a deeper -- level than the type. For a protected object (whose type is an -- anonymous protected type) its components are at the same level -- as the type itself. elsif not Is_Overloadable (E) and then Ekind (Scope (E)) = E_Protected_Type and then Comes_From_Source (Scope (E)) then return Type_Access_Level (Scope (E)) + 1; else return Scope_Depth (Enclosing_Dynamic_Scope (E)); end if; elsif Nkind (Obj) = N_Selected_Component then if Is_Access_Type (Etype (Prefix (Obj))) then return Type_Access_Level (Etype (Prefix (Obj))); else return Object_Access_Level (Prefix (Obj)); end if; elsif Nkind (Obj) = N_Indexed_Component then if Is_Access_Type (Etype (Prefix (Obj))) then return Type_Access_Level (Etype (Prefix (Obj))); else return Object_Access_Level (Prefix (Obj)); end if; 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 Nkind (Prefix (Obj)) = N_Selected_Component and then Ekind (Etype (Prefix (Obj))) = E_Anonymous_Access_Type and then Ekind (Entity (Selector_Name (Prefix (Obj)))) = E_Discriminant then return Object_Access_Level (Prefix (Obj)); else return Type_Access_Level (Etype (Prefix (Obj))); end if; elsif Nkind (Obj) = N_Type_Conversion or else Nkind (Obj) = N_Unchecked_Type_Conversion 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. elsif Nkind (Obj) = N_Function_Call then if Is_Entity_Name (Name (Obj)) then return Subprogram_Access_Level (Entity (Name (Obj))); else return Type_Access_Level (Etype (Prefix (Name (Obj)))); end if; -- For convenience we handle qualified expressions, even though -- they aren't technically object names. elsif Nkind (Obj) = N_Qualified_Expression then return Object_Access_Level (Expression (Obj)); -- Otherwise return the scope level of Standard. -- (If there are cases that fall through -- to this point they will be treated as -- having global accessibility for now. ???) else return Scope_Depth (Standard_Standard); end if; end Object_Access_Level; ----------------------- -- Private_Component -- ----------------------- function Private_Component (Type_Id : Entity_Id) return Entity_Id is Ancestor : constant Entity_Id := Base_Type (Type_Id); function Trace_Components (T : Entity_Id; Check : Boolean) return Entity_Id; -- Recursive function that does the work, and checks against circular -- definition for each subcomponent type. ---------------------- -- Trace_Components -- ---------------------- function Trace_Components (T : Entity_Id; Check : Boolean) return Entity_Id is Btype : constant Entity_Id := Base_Type (T); Component : Entity_Id; P : Entity_Id; Candidate : Entity_Id := Empty; begin if Check and then Btype = Ancestor then Error_Msg_N ("circular type definition", Type_Id); return Any_Type; end if; if Is_Private_Type (Btype) and then not Is_Generic_Type (Btype) then if Present (Full_View (Btype)) 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. Candidate := Trace_Components (Full_View (Btype), True); if Candidate = Any_Type then return Any_Type; else return Btype; end if; else return Btype; end if; elsif Is_Array_Type (Btype) then return Trace_Components (Component_Type (Btype), True); elsif Is_Record_Type (Btype) then Component := First_Entity (Btype); while Present (Component) loop -- Skip anonymous types generated by constrained components if not Is_Type (Component) then P := Trace_Components (Etype (Component), True); if Present (P) then if P = Any_Type then return P; else Candidate := P; end if; end if; end if; Next_Entity (Component); end loop; return Candidate; else return Empty; end if; end Trace_Components; -- Start of processing for Private_Component begin return Trace_Components (Type_Id, False); end Private_Component; ----------------------- -- Process_End_Label -- ----------------------- procedure Process_End_Label (N : Node_Id; Typ : Character; Ent : Entity_Id) is Loc : Source_Ptr; Nam : Node_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. 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. ------------------------- -- Generate_Parent_Ref -- ------------------------- procedure Generate_Parent_Ref (N : Node_Id) is Parent_Ent : Entity_Id; 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; Parent_Ent := Scope (Parent_Ent); end loop; -- 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. return; 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 (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) Endl := End_Label (N); if No (Endl) or else Nkind (Endl) = N_String_Literal then return; end if; -- Reference node is not in extended main source unit 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. if Typ /= 'e' then return; else Label_Ref := False; -- 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); end if; end if; -- Reference is in extended main source unit else Label_Ref := True; -- For designator, generate references for the parent entries 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) if Comes_From_Source (Endl) then Nam := Name (Endl); while Nkind (Nam) = N_Selected_Component loop Generate_Parent_Ref (Selector_Name (Nam)); Nam := Prefix (Nam); end loop; Generate_Parent_Ref (Nam); end if; Endl := Identifier (Endl); end if; end if; -- If the end label is not for the given entity, then either we have -- some previous error, or this is a generic instantiation for which -- we do not need to make a cross-reference in this case anyway. In -- either case we simply ignore the call. if Chars (Ent) /= Chars (Endl) then 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). 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 Label_Ref then if Style_Check then Style.Check_Identifier (Endl, Ent); end if; Generate_Reference (Ent, Endl, 'l', Set_Ref => False); end if; -- Set the location to point past the label (normally this will -- mean the semicolon immediately following the label). This is -- done for the sake of the 'e' or 't' entry generated below. Get_Decoded_Name_String (Chars (Endl)); Set_Sloc (Endl, Sloc (Endl) + Source_Ptr (Name_Len)); end if; -- Now generate the e/t reference Generate_Reference (Ent, Endl, Typ, Set_Ref => False, Force => True); -- Restore Sloc, in case modified above, since we have an identifier -- and the normal Sloc should be left set in the tree. Set_Sloc (Endl, Loc); end Process_End_Label; ------------------ -- Real_Convert -- ------------------ -- We do the conversion to get the value of the real string by using -- the scanner, see Sinput for details on use of the internal source -- buffer for scanning internal strings. function Real_Convert (S : String) return Node_Id is Save_Src : constant Source_Buffer_Ptr := Source; Negative : Boolean; begin Source := Internal_Source_Ptr; Scan_Ptr := 1; for J in S'Range loop Source (Source_Ptr (J)) := S (J); end loop; Source (S'Length + 1) := EOF; if Source (Scan_Ptr) = '-' then Negative := True; Scan_Ptr := Scan_Ptr + 1; else Negative := False; end if; Scan; if Negative then Set_Realval (Token_Node, UR_Negate (Realval (Token_Node))); end if; Source := Save_Src; return Token_Node; end Real_Convert; --------------------- -- Rep_To_Pos_Flag -- --------------------- function Rep_To_Pos_Flag (E : Entity_Id; Loc : Source_Ptr) return Node_Id is begin return New_Occurrence_Of (Boolean_Literals (not Range_Checks_Suppressed (E)), Loc); end Rep_To_Pos_Flag; -------------------- -- Require_Entity -- -------------------- procedure Require_Entity (N : Node_Id) is begin if Is_Entity_Name (N) and then No (Entity (N)) then if Total_Errors_Detected /= 0 then Set_Entity (N, Any_Id); else raise Program_Error; end if; end if; end Require_Entity; ------------------------------ -- Requires_Transient_Scope -- ------------------------------ -- A transient scope is required when variable-sized temporaries are -- allocated in the primary or secondary stack, or when finalization -- actions must be generated before the next instruction. function Requires_Transient_Scope (Id : Entity_Id) return Boolean is Typ : constant Entity_Id := Underlying_Type (Id); -- Start of processing for Requires_Transient_Scope begin -- This is a private type which is not completed yet. This can only -- happen in a default expression (of a formal parameter or of a -- record component). Do not expand transient scope in this case if No (Typ) then return False; -- Do not expand transient scope for non-existent procedure return elsif Typ = Standard_Void_Type then return False; -- Elementary types do not require a transient scope elsif Is_Elementary_Type (Typ) then return False; -- Generally, indefinite subtypes require a transient scope, since the -- back end cannot generate temporaries, since this is not a valid type -- for declaring an object. It might be possible to relax this in the -- future, e.g. by declaring the maximum possible space for the type. elsif Is_Indefinite_Subtype (Typ) then return True; -- Functions returning tagged types may dispatch on result so their -- returned value is allocated on the secondary stack. Controlled -- type temporaries need finalization. elsif Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then return True; -- 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; -- String literal types never require transient scope elsif Ekind (Typ) = E_String_Literal_Subtype then return False; -- Array type. Note that we already know that this is a constrained -- array, since unconstrained arrays will fail the indefinite test. elsif Is_Array_Type (Typ) then -- If component type requires a transient scope, the array does too if Requires_Transient_Scope (Component_Type (Typ)) then return True; -- Otherwise, we only need a transient scope if the size is not -- known at compile time. else return not Size_Known_At_Compile_Time (Typ); end if; -- All other cases do not require a transient scope else return False; end if; end Requires_Transient_Scope; -------------------------- -- Reset_Analyzed_Flags -- -------------------------- procedure Reset_Analyzed_Flags (N : Node_Id) is 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 -- can result in generating auxiliary stuff more than once. -------------------- -- Clear_Analyzed -- -------------------- function Clear_Analyzed (N : Node_Id) return Traverse_Result is begin if not Has_Extension (N) then Set_Analyzed (N, False); end if; return OK; end Clear_Analyzed; function Reset_Analyzed is new Traverse_Func (Clear_Analyzed); Discard : Traverse_Result; pragma Warnings (Off, Discard); -- Start of processing for Reset_Analyzed_Flags begin Discard := Reset_Analyzed (N); end Reset_Analyzed_Flags; --------------------------- -- Safe_To_Capture_Value -- --------------------------- function Safe_To_Capture_Value (N : Node_Id; Ent : Entity_Id) 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. if Ekind (Ent) /= E_Variable and then Ekind (Ent) /= E_Out_Parameter and then Ekind (Ent) /= E_In_Out_Parameter then return False; end if; -- Skip volatile and aliased variables, 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. -- Should we have a flag Has_Address_Clause ??? if Treat_As_Volatile (Ent) or else Is_Aliased (Ent) or else Present (Address_Clause (Ent)) 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. declare E_Scope : constant Entity_Id := Scope (Ent); R_Scope : Entity_Id; begin R_Scope := Current_Scope; while R_Scope /= Standard_Standard loop exit when R_Scope = E_Scope; if Ekind (R_Scope) /= E_Package and then Ekind (R_Scope) /= E_Block then return False; else R_Scope := Scope (R_Scope); end if; end loop; end; -- 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). declare 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_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 Desc := P; P := Parent (P); end if; end loop; end; -- OK, looks safe to set value return True; end Safe_To_Capture_Value; --------------- -- Same_Name -- --------------- function Same_Name (N1, N2 : Node_Id) return Boolean is K1 : constant Node_Kind := Nkind (N1); K2 : constant Node_Kind := Nkind (N2); begin if (K1 = N_Identifier or else K1 = N_Defining_Identifier) and then (K2 = N_Identifier or else K2 = N_Defining_Identifier) then return Chars (N1) = Chars (N2); elsif (K1 = N_Selected_Component or else K1 = N_Expanded_Name) and then (K2 = N_Selected_Component or else K2 = N_Expanded_Name) then return Same_Name (Selector_Name (N1), Selector_Name (N2)) and then Same_Name (Prefix (N1), Prefix (N2)); else return False; end if; end Same_Name; --------------- -- Same_Type -- --------------- function Same_Type (T1, T2 : Entity_Id) return Boolean is begin if T1 = T2 then return True; elsif not Is_Constrained (T1) and then not Is_Constrained (T2) and then Base_Type (T1) = Base_Type (T2) then return True; -- For now don't bother with case of identical constraints, to be -- fiddled with later on perhaps (this is only used for optimization -- purposes, so it is not critical to do a best possible job) else return False; end if; end Same_Type; ------------------------ -- Scope_Is_Transient -- ------------------------ function Scope_Is_Transient return Boolean is begin return Scope_Stack.Table (Scope_Stack.Last).Is_Transient; end Scope_Is_Transient; ------------------ -- Scope_Within -- ------------------ function Scope_Within (Scope1, Scope2 : Entity_Id) return Boolean is Scop : Entity_Id; begin Scop := Scope1; while Scop /= Standard_Standard loop Scop := Scope (Scop); if Scop = Scope2 then return True; end if; end loop; return False; end Scope_Within; -------------------------- -- Scope_Within_Or_Same -- -------------------------- function Scope_Within_Or_Same (Scope1, Scope2 : Entity_Id) return Boolean is Scop : Entity_Id; begin Scop := Scope1; while Scop /= Standard_Standard loop if Scop = Scope2 then return True; else Scop := Scope (Scop); end if; end loop; return False; end Scope_Within_Or_Same; ------------------------ -- Set_Current_Entity -- ------------------------ -- The given entity is to be set as the currently visible definition -- of its associated name (i.e. the Node_Id associated with its name). -- All we have to do is to get the name from the identifier, and -- then set the associated Node_Id to point to the given entity. procedure Set_Current_Entity (E : Entity_Id) is begin Set_Name_Entity_Id (Chars (E), E); end Set_Current_Entity; --------------------------------- -- Set_Entity_With_Style_Check -- --------------------------------- procedure Set_Entity_With_Style_Check (N : Node_Id; Val : Entity_Id) is Val_Actual : Entity_Id; Nod : Node_Id; begin Set_Entity (N, Val); if Style_Check and then not Suppress_Style_Checks (Val) and then not In_Instance then if Nkind (N) = N_Identifier then Nod := N; elsif Nkind (N) = N_Expanded_Name then Nod := Selector_Name (N); else return; end if; -- 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 or else Is_Subprogram (Val_Actual) or else Is_Generic_Subprogram (Val_Actual)) and then Present (Alias (Val_Actual)) loop Val_Actual := Alias (Val_Actual); end loop; -- Renaming declarations for generic actuals do not come from source, -- and have a different name from that of the entity they rename, so -- there is no style check to perform here. if Chars (Nod) = Chars (Val_Actual) then Style.Check_Identifier (Nod, Val_Actual); end if; end if; Set_Entity (N, Val); end Set_Entity_With_Style_Check; ------------------------ -- Set_Name_Entity_Id -- ------------------------ procedure Set_Name_Entity_Id (Id : Name_Id; Val : Entity_Id) is begin Set_Name_Table_Info (Id, Int (Val)); end Set_Name_Entity_Id; --------------------- -- Set_Next_Actual -- --------------------- procedure Set_Next_Actual (Ass1_Id : Node_Id; Ass2_Id : Node_Id) is begin if Nkind (Parent (Ass1_Id)) = N_Parameter_Association then Set_First_Named_Actual (Parent (Ass1_Id), Ass2_Id); end if; end Set_Next_Actual; ----------------------- -- Set_Public_Status -- ----------------------- procedure Set_Public_Status (Id : Entity_Id) is S : constant Entity_Id := Current_Scope; begin -- 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 declaration that occurs in a handled sequence of statements -- is the declaration for a temporary object generated by the expander. -- It never needs to be made public and furthermore, making it public -- can cause back end problems if it is of variable size. elsif Nkind (Parent (Id)) = N_Object_Declaration and then Nkind (Parent (Parent (Id))) = N_Handled_Sequence_Of_Statements 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_Concurrent_Type (S) and then not Has_Completion (S) and then Nkind (Parent (Id)) = N_Object_Declaration then Set_Is_Public (Id); end if; end Set_Public_Status; ---------------------------- -- Set_Scope_Is_Transient -- ---------------------------- procedure Set_Scope_Is_Transient (V : Boolean := True) is begin Scope_Stack.Table (Scope_Stack.Last).Is_Transient := V; end Set_Scope_Is_Transient; ------------------- -- Set_Size_Info -- ------------------- procedure Set_Size_Info (T1, T2 : Entity_Id) is begin -- We copy Esize, but not RM_Size, since in general RM_Size is -- subtype specific and does not get inherited by all subtypes. Set_Esize (T1, Esize (T2)); Set_Has_Biased_Representation (T1, Has_Biased_Representation (T2)); if Is_Discrete_Or_Fixed_Point_Type (T1) and then Is_Discrete_Or_Fixed_Point_Type (T2) then Set_Is_Unsigned_Type (T1, Is_Unsigned_Type (T2)); end if; Set_Alignment (T1, Alignment (T2)); end Set_Size_Info; -------------------- -- Static_Integer -- -------------------- function Static_Integer (N : Node_Id) return Uint is begin Analyze_And_Resolve (N, Any_Integer); if N = Error or else Error_Posted (N) or else Etype (N) = Any_Type then return No_Uint; end if; if Is_Static_Expression (N) then if not Raises_Constraint_Error (N) then return Expr_Value (N); else return No_Uint; end if; elsif Etype (N) = Any_Type then return No_Uint; else Flag_Non_Static_Expr ("static integer expression required here", N); return No_Uint; end if; end Static_Integer; -------------------------- -- Statically_Different -- -------------------------- function Statically_Different (E1, E2 : Node_Id) return Boolean is R1 : constant Node_Id := Get_Referenced_Object (E1); R2 : constant Node_Id := Get_Referenced_Object (E2); begin return Is_Entity_Name (R1) and then Is_Entity_Name (R2) and then Entity (R1) /= Entity (R2) and then not Is_Formal (Entity (R1)) and then not Is_Formal (Entity (R2)); end Statically_Different; ----------------------------- -- Subprogram_Access_Level -- ----------------------------- function Subprogram_Access_Level (Subp : Entity_Id) return Uint is begin if Present (Alias (Subp)) then return Subprogram_Access_Level (Alias (Subp)); else return Scope_Depth (Enclosing_Dynamic_Scope (Subp)); end if; end Subprogram_Access_Level; ----------------- -- Trace_Scope -- ----------------- procedure Trace_Scope (N : Node_Id; E : Entity_Id; Msg : String) is begin if Debug_Flag_W then for J in 0 .. Scope_Stack.Last loop Write_Str (" "); end loop; Write_Str (Msg); Write_Name (Chars (E)); Write_Str (" line "); Write_Int (Int (Get_Logical_Line_Number (Sloc (N)))); Write_Eol; end if; end Trace_Scope; ----------------------- -- Transfer_Entities -- ----------------------- procedure Transfer_Entities (From : Entity_Id; To : Entity_Id) is Ent : Entity_Id := First_Entity (From); begin if No (Ent) then return; end if; if (Last_Entity (To)) = Empty then Set_First_Entity (To, Ent); else Set_Next_Entity (Last_Entity (To), Ent); end if; Set_Last_Entity (To, Last_Entity (From)); while Present (Ent) loop Set_Scope (Ent, To); if not Is_Public (Ent) then Set_Public_Status (Ent); if Is_Public (Ent) and then Ekind (Ent) = E_Record_Subtype then -- The components of the propagated Itype must be public -- as well. declare Comp : Entity_Id; begin Comp := First_Entity (Ent); while Present (Comp) loop Set_Is_Public (Comp); Next_Entity (Comp); end loop; end; end if; end if; Next_Entity (Ent); end loop; Set_First_Entity (From, Empty); Set_Last_Entity (From, Empty); end Transfer_Entities; ----------------------- -- Type_Access_Level -- ----------------------- function Type_Access_Level (Typ : Entity_Id) return Uint 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); 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); end if; Btyp := Root_Type (Btyp); end if; return Scope_Depth (Enclosing_Dynamic_Scope (Btyp)); end Type_Access_Level; -------------------------- -- Unit_Declaration_Node -- -------------------------- function Unit_Declaration_Node (Unit_Id : Entity_Id) return Node_Id is N : Node_Id := Parent (Unit_Id); begin -- Predefined operators do not have a full function declaration if Ekind (Unit_Id) = E_Operator then return N; end if; while Nkind (N) /= N_Abstract_Subprogram_Declaration and then Nkind (N) /= N_Formal_Package_Declaration and then Nkind (N) /= N_Function_Instantiation and then Nkind (N) /= N_Generic_Package_Declaration and then Nkind (N) /= N_Generic_Subprogram_Declaration and then Nkind (N) /= N_Package_Declaration and then Nkind (N) /= N_Package_Body and then Nkind (N) /= N_Package_Instantiation and then Nkind (N) /= N_Package_Renaming_Declaration and then Nkind (N) /= N_Procedure_Instantiation and then Nkind (N) /= N_Protected_Body and then Nkind (N) /= N_Subprogram_Declaration and then Nkind (N) /= N_Subprogram_Body and then Nkind (N) /= N_Subprogram_Body_Stub and then Nkind (N) /= N_Subprogram_Renaming_Declaration and then Nkind (N) /= N_Task_Body and then Nkind (N) /= N_Task_Type_Declaration and then Nkind (N) not in N_Formal_Subprogram_Declaration and then Nkind (N) not in N_Generic_Renaming_Declaration loop N := Parent (N); pragma Assert (Present (N)); end loop; return N; end Unit_Declaration_Node; ------------------------------ -- Universal_Interpretation -- ------------------------------ function Universal_Interpretation (Opnd : Node_Id) return Entity_Id is Index : Interp_Index; It : Interp; begin -- The argument may be a formal parameter of an operator or subprogram -- with multiple interpretations, or else an expression for an actual. if Nkind (Opnd) = N_Defining_Identifier or else not Is_Overloaded (Opnd) then if Etype (Opnd) = Universal_Integer or else Etype (Opnd) = Universal_Real then return Etype (Opnd); else return Empty; end if; else Get_First_Interp (Opnd, Index, It); while Present (It.Typ) loop if It.Typ = Universal_Integer or else It.Typ = Universal_Real then return It.Typ; end if; Get_Next_Interp (Index, It); end loop; return Empty; end if; end Universal_Interpretation; ---------------------- -- Within_Init_Proc -- ---------------------- function Within_Init_Proc return Boolean is S : Entity_Id; begin S := Current_Scope; while not Is_Overloadable (S) loop if S = Standard_Standard then return False; else S := Scope (S); end if; end loop; return Is_Init_Proc (S); end Within_Init_Proc; ---------------- -- Wrong_Type -- ---------------- procedure Wrong_Type (Expr : Node_Id; Expected_Type : Entity_Id) is Found_Type : constant Entity_Id := First_Subtype (Etype (Expr)); Expec_Type : constant Entity_Id := First_Subtype (Expected_Type); function Has_One_Matching_Field return Boolean; -- Determines if Expec_Type is a record type with a single component or -- discriminant whose type matches the found type or is one dimensional -- array whose component type matches the found type. ---------------------------- -- Has_One_Matching_Field -- ---------------------------- function Has_One_Matching_Field return Boolean is E : Entity_Id; begin if Is_Array_Type (Expec_Type) and then Number_Dimensions (Expec_Type) = 1 and then Covers (Etype (Component_Type (Expec_Type)), Found_Type) then return True; elsif not Is_Record_Type (Expec_Type) then return False; else E := First_Entity (Expec_Type); loop if No (E) then return False; elsif (Ekind (E) /= E_Discriminant and then Ekind (E) /= E_Component) or else (Chars (E) = Name_uTag or else Chars (E) = Name_uParent) then Next_Entity (E); else exit; end if; end loop; if not Covers (Etype (E), Found_Type) then return False; elsif Present (Next_Entity (E)) then return False; else return True; end if; end if; end Has_One_Matching_Field; -- Start of processing for Wrong_Type begin -- Don't output message if either type is Any_Type, or if a message -- has already been posted for this node. We need to do the latter -- check explicitly (it is ordinarily done in Errout), because we -- are using ! to force the output of the error messages. if Expec_Type = Any_Type or else Found_Type = Any_Type or else Error_Posted (Expr) then return; -- In an instance, there is an ongoing problem with completion of -- type derived from private types. Their structure is what Gigi -- expects, but the Etype is the parent type rather than the -- derived private type itself. Do not flag error in this case. The -- private completion is an entity without a parent, like an Itype. -- Similarly, full and partial views may be incorrect in the instance. -- 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) or else Has_Private_Declaration (Etype (Expr))) and then No (Parent (Expected_Type)) then return; end if; end if; -- An interesting special check. If the expression is parenthesized -- and its type corresponds to the type of the sole component of the -- expected record type, or to the component type of the expected one -- dimensional array type, then assume we have a bad aggregate attempt. if Nkind (Expr) in N_Subexpr and then Paren_Count (Expr) /= 0 and then Has_One_Matching_Field then Error_Msg_N ("positional aggregate cannot have one component", Expr); -- Another special check, if we are looking for a pool-specific access -- type and we found an E_Access_Attribute_Type, then we have the case -- of an Access attribute being used in a context which needs a pool- -- specific type, which is never allowed. The one extra check we make -- is that the expected designated type covers the Found_Type. elsif Is_Access_Type (Expec_Type) and then Ekind (Found_Type) = E_Access_Attribute_Type and then Ekind (Base_Type (Expec_Type)) /= E_General_Access_Type and then Ekind (Base_Type (Expec_Type)) /= E_Anonymous_Access_Type and then Covers (Designated_Type (Expec_Type), Designated_Type (Found_Type)) then Error_Msg_N ("result must be general access type!", Expr); Error_Msg_NE ("add ALL to }!", Expr, Expec_Type); -- If the expected type is an anonymous access type, as for access -- parameters and discriminants, the error is on the designated types. elsif Ekind (Expec_Type) = E_Anonymous_Access_Type then if Comes_From_Source (Expec_Type) then Error_Msg_NE ("expected}!", Expr, Expec_Type); else Error_Msg_NE ("expected an access type with designated}", Expr, Designated_Type (Expec_Type)); end if; if Is_Access_Type (Found_Type) and then not Comes_From_Source (Found_Type) then Error_Msg_NE ("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)); else Error_Msg_NE ("found}!", Expr, Found_Type); end if; end if; -- 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. declare Expec_Scope : Entity_Id; Found_Scope : Entity_Id; begin Expec_Scope := Expec_Type; Found_Scope := Found_Type; for Levels in Int range 0 .. 3 loop if Chars (Expec_Scope) /= Chars (Found_Scope) then Error_Msg_Qual_Level := Levels; exit; end if; Expec_Scope := Scope (Expec_Scope); Found_Scope := Scope (Found_Scope); exit when Expec_Scope = Standard_Standard or else Found_Scope = Standard_Standard or else not Comes_From_Source (Expec_Scope) or else not Comes_From_Source (Found_Scope); end loop; end; if Is_Record_Type (Expec_Type) and then Present (Corresponding_Remote_Type (Expec_Type)) then Error_Msg_NE ("expected}!", Expr, Corresponding_Remote_Type (Expec_Type)); else Error_Msg_NE ("expected}!", Expr, Expec_Type); end if; if Is_Entity_Name (Expr) and then Is_Package_Or_Generic_Package (Entity (Expr)) then Error_Msg_N ("found package name!", Expr); elsif Is_Entity_Name (Expr) and then (Ekind (Entity (Expr)) = E_Procedure or else Ekind (Entity (Expr)) = E_Generic_Procedure) then if Ekind (Expec_Type) = E_Access_Subprogram_Type then Error_Msg_N ("found procedure name, possibly missing Access attribute!", Expr); else Error_Msg_N ("found procedure name instead of function!", Expr); end if; elsif Nkind (Expr) = N_Function_Call and then Ekind (Expec_Type) = E_Access_Subprogram_Type and then Etype (Designated_Type (Expec_Type)) = Etype (Expr) and then No (Parameter_Associations (Expr)) then Error_Msg_N ("found function name, possibly missing Access attribute!", Expr); -- Catch common error: a prefix or infix operator which is not -- directly visible because the type isn't. elsif Nkind (Expr) in N_Op and then Is_Overloaded (Expr) and then not Is_Immediately_Visible (Expec_Type) and then not Is_Potentially_Use_Visible (Expec_Type) and then not In_Use (Expec_Type) and then Has_Compatible_Type (Right_Opnd (Expr), Expec_Type) then Error_Msg_N ("operator of the type is not directly visible!", Expr); elsif Ekind (Found_Type) = E_Void 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); else Error_Msg_NE ("found}!", Expr, Found_Type); end if; Error_Msg_Qual_Level := 0; end if; end Wrong_Type; end Sem_Util;
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