------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- F R E E Z E -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2006, 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 Debug; use Debug; with Einfo; use Einfo; with Elists; use Elists; with Errout; use Errout; with Exp_Ch7; use Exp_Ch7; with Exp_Pakd; use Exp_Pakd; with Exp_Util; use Exp_Util; with Exp_Tss; use Exp_Tss; with Layout; use Layout; with Lib.Xref; use Lib.Xref; with Nlists; use Nlists; with Nmake; use Nmake; with Opt; use Opt; with Restrict; use Restrict; with Rident; use Rident; with Sem; use Sem; with Sem_Cat; use Sem_Cat; with Sem_Ch6; use Sem_Ch6; with Sem_Ch7; use Sem_Ch7; with Sem_Ch8; use Sem_Ch8; with Sem_Ch13; use Sem_Ch13; with Sem_Eval; use Sem_Eval; with Sem_Mech; use Sem_Mech; with Sem_Prag; use Sem_Prag; with Sem_Res; use Sem_Res; with Sem_Util; use Sem_Util; with Sinfo; use Sinfo; with Snames; use Snames; with Stand; use Stand; with Targparm; use Targparm; with Tbuild; use Tbuild; with Ttypes; use Ttypes; with Uintp; use Uintp; with Urealp; use Urealp; package body Freeze is ----------------------- -- Local Subprograms -- ----------------------- procedure Adjust_Esize_For_Alignment (Typ : Entity_Id); -- Typ is a type that is being frozen. If no size clause is given, -- but a default Esize has been computed, then this default Esize is -- adjusted up if necessary to be consistent with a given alignment, -- but never to a value greater than Long_Long_Integer'Size. This -- is used for all discrete types and for fixed-point types. procedure Build_And_Analyze_Renamed_Body (Decl : Node_Id; New_S : Entity_Id; After : in out Node_Id); -- Build body for a renaming declaration, insert in tree and analyze procedure Check_Address_Clause (E : Entity_Id); -- Apply legality checks to address clauses for object declarations, -- at the point the object is frozen. procedure Check_Strict_Alignment (E : Entity_Id); -- E is a base type. If E is tagged or has a component that is aliased -- or tagged or contains something this is aliased or tagged, set -- Strict_Alignment. procedure Check_Unsigned_Type (E : Entity_Id); pragma Inline (Check_Unsigned_Type); -- If E is a fixed-point or discrete type, then all the necessary work -- to freeze it is completed except for possible setting of the flag -- Is_Unsigned_Type, which is done by this procedure. The call has no -- effect if the entity E is not a discrete or fixed-point type. procedure Freeze_And_Append (Ent : Entity_Id; Loc : Source_Ptr; Result : in out List_Id); -- Freezes Ent using Freeze_Entity, and appends the resulting list of -- nodes to Result, modifying Result from No_List if necessary. procedure Freeze_Enumeration_Type (Typ : Entity_Id); -- Freeze enumeration type. The Esize field is set as processing -- proceeds (i.e. set by default when the type is declared and then -- adjusted by rep clauses. What this procedure does is to make sure -- that if a foreign convention is specified, and no specific size -- is given, then the size must be at least Integer'Size. procedure Freeze_Static_Object (E : Entity_Id); -- If an object is frozen which has Is_Statically_Allocated set, then -- all referenced types must also be marked with this flag. This routine -- is in charge of meeting this requirement for the object entity E. procedure Freeze_Subprogram (E : Entity_Id); -- Perform freezing actions for a subprogram (create extra formals, -- and set proper default mechanism values). Note that this routine -- is not called for internal subprograms, for which neither of these -- actions is needed (or desirable, we do not want for example to have -- these extra formals present in initialization procedures, where they -- would serve no purpose). In this call E is either a subprogram or -- a subprogram type (i.e. an access to a subprogram). function Is_Fully_Defined (T : Entity_Id) return Boolean; -- True if T is not private and has no private components, or has a full -- view. Used to determine whether the designated type of an access type -- should be frozen when the access type is frozen. This is done when an -- allocator is frozen, or an expression that may involve attributes of -- the designated type. Otherwise freezing the access type does not freeze -- the designated type. procedure Process_Default_Expressions (E : Entity_Id; After : in out Node_Id); -- This procedure is called for each subprogram to complete processing -- of default expressions at the point where all types are known to be -- frozen. The expressions must be analyzed in full, to make sure that -- all error processing is done (they have only been pre-analyzed). If -- the expression is not an entity or literal, its analysis may generate -- code which must not be executed. In that case we build a function -- body to hold that code. This wrapper function serves no other purpose -- (it used to be called to evaluate the default, but now the default is -- inlined at each point of call). procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id); -- Typ is a record or array type that is being frozen. This routine -- sets the default component alignment from the scope stack values -- if the alignment is otherwise not specified. procedure Check_Debug_Info_Needed (T : Entity_Id); -- As each entity is frozen, this routine is called to deal with the -- setting of Debug_Info_Needed for the entity. This flag is set if -- the entity comes from source, or if we are in Debug_Generated_Code -- mode or if the -gnatdV debug flag is set. However, it never sets -- the flag if Debug_Info_Off is set. procedure Set_Debug_Info_Needed (T : Entity_Id); -- Sets the Debug_Info_Needed flag on entity T if not already set, and -- also on any entities that are needed by T (for an object, the type -- of the object is needed, and for a type, the subsidiary types are -- needed -- see body for details). Never has any effect on T if the -- Debug_Info_Off flag is set. procedure Undelay_Type (T : Entity_Id); -- T is a type of a component that we know to be an Itype. -- We don't want this to have a Freeze_Node, so ensure it doesn't. -- Do the same for any Full_View or Corresponding_Record_Type. procedure Warn_Overlay (Expr : Node_Id; Typ : Entity_Id; Nam : Node_Id); -- Expr is the expression for an address clause for entity Nam whose type -- is Typ. If Typ has a default initialization, and there is no explicit -- initialization in the source declaration, check whether the address -- clause might cause overlaying of an entity, and emit a warning on the -- side effect that the initialization will cause. ------------------------------- -- Adjust_Esize_For_Alignment -- ------------------------------- procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is Align : Uint; begin if Known_Esize (Typ) and then Known_Alignment (Typ) then Align := Alignment_In_Bits (Typ); if Align > Esize (Typ) and then Align <= Standard_Long_Long_Integer_Size then Set_Esize (Typ, Align); end if; end if; end Adjust_Esize_For_Alignment; ------------------------------------ -- Build_And_Analyze_Renamed_Body -- ------------------------------------ procedure Build_And_Analyze_Renamed_Body (Decl : Node_Id; New_S : Entity_Id; After : in out Node_Id) is Body_Node : constant Node_Id := Build_Renamed_Body (Decl, New_S); begin Insert_After (After, Body_Node); Mark_Rewrite_Insertion (Body_Node); Analyze (Body_Node); After := Body_Node; end Build_And_Analyze_Renamed_Body; ------------------------ -- Build_Renamed_Body -- ------------------------ function Build_Renamed_Body (Decl : Node_Id; New_S : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (New_S); -- We use for the source location of the renamed body, the location -- of the spec entity. It might seem more natural to use the location -- of the renaming declaration itself, but that would be wrong, since -- then the body we create would look as though it was created far -- too late, and this could cause problems with elaboration order -- analysis, particularly in connection with instantiations. N : constant Node_Id := Unit_Declaration_Node (New_S); Nam : constant Node_Id := Name (N); Old_S : Entity_Id; Spec : constant Node_Id := New_Copy_Tree (Specification (Decl)); Actuals : List_Id := No_List; Call_Node : Node_Id; Call_Name : Node_Id; Body_Node : Node_Id; Formal : Entity_Id; O_Formal : Entity_Id; Param_Spec : Node_Id; begin -- Determine the entity being renamed, which is the target of the -- call statement. If the name is an explicit dereference, this is -- a renaming of a subprogram type rather than a subprogram. The -- name itself is fully analyzed. if Nkind (Nam) = N_Selected_Component then Old_S := Entity (Selector_Name (Nam)); elsif Nkind (Nam) = N_Explicit_Dereference then Old_S := Etype (Nam); elsif Nkind (Nam) = N_Indexed_Component then if Is_Entity_Name (Prefix (Nam)) then Old_S := Entity (Prefix (Nam)); else Old_S := Entity (Selector_Name (Prefix (Nam))); end if; elsif Nkind (Nam) = N_Character_Literal then Old_S := Etype (New_S); else Old_S := Entity (Nam); end if; if Is_Entity_Name (Nam) then -- If the renamed entity is a predefined operator, retain full -- name to ensure its visibility. if Ekind (Old_S) = E_Operator and then Nkind (Nam) = N_Expanded_Name then Call_Name := New_Copy (Name (N)); else Call_Name := New_Reference_To (Old_S, Loc); end if; else Call_Name := New_Copy (Name (N)); -- The original name may have been overloaded, but -- is fully resolved now. Set_Is_Overloaded (Call_Name, False); end if; -- For simple renamings, subsequent calls can be expanded directly -- as called to the renamed entity. The body must be generated in -- any case for calls they may appear elsewhere. if (Ekind (Old_S) = E_Function or else Ekind (Old_S) = E_Procedure) and then Nkind (Decl) = N_Subprogram_Declaration then Set_Body_To_Inline (Decl, Old_S); end if; -- The body generated for this renaming is an internal artifact, and -- does not constitute a freeze point for the called entity. Set_Must_Not_Freeze (Call_Name); Formal := First_Formal (Defining_Entity (Decl)); if Present (Formal) then Actuals := New_List; while Present (Formal) loop Append (New_Reference_To (Formal, Loc), Actuals); Next_Formal (Formal); end loop; end if; -- If the renamed entity is an entry, inherit its profile. For -- other renamings as bodies, both profiles must be subtype -- conformant, so it is not necessary to replace the profile given -- in the declaration. However, default values that are aggregates -- are rewritten when partially analyzed, so we recover the original -- aggregate to insure that subsequent conformity checking works. -- Similarly, if the default expression was constant-folded, recover -- the original expression. Formal := First_Formal (Defining_Entity (Decl)); if Present (Formal) then O_Formal := First_Formal (Old_S); Param_Spec := First (Parameter_Specifications (Spec)); while Present (Formal) loop if Is_Entry (Old_S) then if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then Set_Etype (Formal, Etype (O_Formal)); Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal)); end if; elsif Nkind (Default_Value (O_Formal)) = N_Aggregate or else Nkind (Original_Node (Default_Value (O_Formal))) /= Nkind (Default_Value (O_Formal)) then Set_Expression (Param_Spec, New_Copy_Tree (Original_Node (Default_Value (O_Formal)))); end if; Next_Formal (Formal); Next_Formal (O_Formal); Next (Param_Spec); end loop; end if; -- If the renamed entity is a function, the generated body contains a -- return statement. Otherwise, build a procedure call. If the entity is -- an entry, subsequent analysis of the call will transform it into the -- proper entry or protected operation call. If the renamed entity is -- a character literal, return it directly. if Ekind (Old_S) = E_Function or else Ekind (Old_S) = E_Operator or else (Ekind (Old_S) = E_Subprogram_Type and then Etype (Old_S) /= Standard_Void_Type) then Call_Node := Make_Return_Statement (Loc, Expression => Make_Function_Call (Loc, Name => Call_Name, Parameter_Associations => Actuals)); elsif Ekind (Old_S) = E_Enumeration_Literal then Call_Node := Make_Return_Statement (Loc, Expression => New_Occurrence_Of (Old_S, Loc)); elsif Nkind (Nam) = N_Character_Literal then Call_Node := Make_Return_Statement (Loc, Expression => Call_Name); else Call_Node := Make_Procedure_Call_Statement (Loc, Name => Call_Name, Parameter_Associations => Actuals); end if; -- Create entities for subprogram body and formals Set_Defining_Unit_Name (Spec, Make_Defining_Identifier (Loc, Chars => Chars (New_S))); Param_Spec := First (Parameter_Specifications (Spec)); while Present (Param_Spec) loop Set_Defining_Identifier (Param_Spec, Make_Defining_Identifier (Loc, Chars => Chars (Defining_Identifier (Param_Spec)))); Next (Param_Spec); end loop; Body_Node := Make_Subprogram_Body (Loc, Specification => Spec, Declarations => New_List, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List (Call_Node))); if Nkind (Decl) /= N_Subprogram_Declaration then Rewrite (N, Make_Subprogram_Declaration (Loc, Specification => Specification (N))); end if; -- Link the body to the entity whose declaration it completes. If -- the body is analyzed when the renamed entity is frozen, it may be -- necessary to restore the proper scope (see package Exp_Ch13). if Nkind (N) = N_Subprogram_Renaming_Declaration and then Present (Corresponding_Spec (N)) then Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N)); else Set_Corresponding_Spec (Body_Node, New_S); end if; return Body_Node; end Build_Renamed_Body; -------------------------- -- Check_Address_Clause -- -------------------------- procedure Check_Address_Clause (E : Entity_Id) is Addr : constant Node_Id := Address_Clause (E); Expr : Node_Id; Decl : constant Node_Id := Declaration_Node (E); Typ : constant Entity_Id := Etype (E); begin if Present (Addr) then Expr := Expression (Addr); -- If we have no initialization of any kind, then we don't -- need to place any restrictions on the address clause, because -- the object will be elaborated after the address clause is -- evaluated. This happens if the declaration has no initial -- expression, or the type has no implicit initialization, or -- the object is imported. -- The same holds for all initialized scalar types and all -- access types. Packed bit arrays of size up to 64 are -- represented using a modular type with an initialization -- (to zero) and can be processed like other initialized -- scalar types. -- If the type is controlled, code to attach the object to a -- finalization chain is generated at the point of declaration, -- and therefore the elaboration of the object cannot be delayed: -- the address expression must be a constant. if (No (Expression (Decl)) and then not Controlled_Type (Typ) and then (not Has_Non_Null_Base_Init_Proc (Typ) or else Is_Imported (E))) or else (Present (Expression (Decl)) and then Is_Scalar_Type (Typ)) or else Is_Access_Type (Typ) or else (Is_Bit_Packed_Array (Typ) and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))) then null; -- Otherwise, we require the address clause to be constant -- because the call to the initialization procedure (or the -- attach code) has to happen at the point of the declaration. else Check_Constant_Address_Clause (Expr, E); Set_Has_Delayed_Freeze (E, False); end if; if not Error_Posted (Expr) and then not Controlled_Type (Typ) then Warn_Overlay (Expr, Typ, Name (Addr)); end if; end if; end Check_Address_Clause; ----------------------------- -- Check_Compile_Time_Size -- ----------------------------- procedure Check_Compile_Time_Size (T : Entity_Id) is procedure Set_Small_Size (T : Entity_Id; S : Uint); -- Sets the compile time known size (32 bits or less) in the Esize -- field, of T checking for a size clause that was given which attempts -- to give a smaller size. function Size_Known (T : Entity_Id) return Boolean; -- Recursive function that does all the work function Static_Discriminated_Components (T : Entity_Id) return Boolean; -- If T is a constrained subtype, its size is not known if any of its -- discriminant constraints is not static and it is not a null record. -- The test is conservative and doesn't check that the components are -- in fact constrained by non-static discriminant values. Could be made -- more precise ??? -------------------- -- Set_Small_Size -- -------------------- procedure Set_Small_Size (T : Entity_Id; S : Uint) is begin if S > 32 then return; elsif Has_Size_Clause (T) then if RM_Size (T) < S then Error_Msg_Uint_1 := S; Error_Msg_NE ("size for & is too small, minimum is ^", Size_Clause (T), T); elsif Unknown_Esize (T) then Set_Esize (T, S); end if; -- Set sizes if not set already else if Unknown_Esize (T) then Set_Esize (T, S); end if; if Unknown_RM_Size (T) then Set_RM_Size (T, S); end if; end if; end Set_Small_Size; ---------------- -- Size_Known -- ---------------- function Size_Known (T : Entity_Id) return Boolean is Index : Entity_Id; Comp : Entity_Id; Ctyp : Entity_Id; Low : Node_Id; High : Node_Id; begin if Size_Known_At_Compile_Time (T) then return True; elsif Is_Scalar_Type (T) or else Is_Task_Type (T) then return not Is_Generic_Type (T); elsif Is_Array_Type (T) then if Ekind (T) = E_String_Literal_Subtype then Set_Small_Size (T, Component_Size (T) * String_Literal_Length (T)); return True; elsif not Is_Constrained (T) then return False; -- Don't do any recursion on type with error posted, since -- we may have a malformed type that leads us into a loop elsif Error_Posted (T) then return False; elsif not Size_Known (Component_Type (T)) then return False; end if; -- Check for all indexes static, and also compute possible -- size (in case it is less than 32 and may be packable). declare Esiz : Uint := Component_Size (T); Dim : Uint; begin Index := First_Index (T); while Present (Index) loop if Nkind (Index) = N_Range then Get_Index_Bounds (Index, Low, High); elsif Error_Posted (Scalar_Range (Etype (Index))) then return False; else Low := Type_Low_Bound (Etype (Index)); High := Type_High_Bound (Etype (Index)); end if; if not Compile_Time_Known_Value (Low) or else not Compile_Time_Known_Value (High) or else Etype (Index) = Any_Type then return False; else Dim := Expr_Value (High) - Expr_Value (Low) + 1; if Dim >= 0 then Esiz := Esiz * Dim; else Esiz := Uint_0; end if; end if; Next_Index (Index); end loop; Set_Small_Size (T, Esiz); return True; end; elsif Is_Access_Type (T) then return True; elsif Is_Private_Type (T) and then not Is_Generic_Type (T) and then Present (Underlying_Type (T)) then -- Don't do any recursion on type with error posted, since -- we may have a malformed type that leads us into a loop if Error_Posted (T) then return False; else return Size_Known (Underlying_Type (T)); end if; elsif Is_Record_Type (T) then -- A class-wide type is never considered to have a known size if Is_Class_Wide_Type (T) then return False; -- A subtype of a variant record must not have non-static -- discriminanted components. elsif T /= Base_Type (T) and then not Static_Discriminated_Components (T) then return False; -- Don't do any recursion on type with error posted, since -- we may have a malformed type that leads us into a loop elsif Error_Posted (T) then return False; end if; -- Now look at the components of the record declare -- The following two variables are used to keep track of -- the size of packed records if we can tell the size of -- the packed record in the front end. Packed_Size_Known -- is True if so far we can figure out the size. It is -- initialized to True for a packed record, unless the -- record has discriminants. The reason we eliminate the -- discriminated case is that we don't know the way the -- back end lays out discriminated packed records. If -- Packed_Size_Known is True, then Packed_Size is the -- size in bits so far. Packed_Size_Known : Boolean := Is_Packed (T) and then not Has_Discriminants (T); Packed_Size : Uint := Uint_0; begin -- Test for variant part present if Has_Discriminants (T) and then Present (Parent (T)) and then Nkind (Parent (T)) = N_Full_Type_Declaration and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition and then not Null_Present (Type_Definition (Parent (T))) and then Present (Variant_Part (Component_List (Type_Definition (Parent (T))))) then -- If variant part is present, and type is unconstrained, -- then we must have defaulted discriminants, or a size -- clause must be present for the type, or else the size -- is definitely not known at compile time. if not Is_Constrained (T) and then No (Discriminant_Default_Value (First_Discriminant (T))) and then Unknown_Esize (T) then return False; end if; end if; -- Loop through components Comp := First_Entity (T); while Present (Comp) loop if Ekind (Comp) = E_Component or else Ekind (Comp) = E_Discriminant then Ctyp := Etype (Comp); -- We do not know the packed size if there is a -- component clause present (we possibly could, -- but this would only help in the case of a record -- with partial rep clauses. That's because in the -- case of full rep clauses, the size gets figured -- out anyway by a different circuit). if Present (Component_Clause (Comp)) then Packed_Size_Known := False; end if; -- We need to identify a component that is an array -- where the index type is an enumeration type with -- non-standard representation, and some bound of the -- type depends on a discriminant. -- This is because gigi computes the size by doing a -- substituation of the appropriate discriminant value -- in the size expression for the base type, and gigi -- is not clever enough to evaluate the resulting -- expression (which involves a call to rep_to_pos) -- at compile time. -- It would be nice if gigi would either recognize that -- this expression can be computed at compile time, or -- alternatively figured out the size from the subtype -- directly, where all the information is at hand ??? if Is_Array_Type (Etype (Comp)) and then Present (Packed_Array_Type (Etype (Comp))) then declare Ocomp : constant Entity_Id := Original_Record_Component (Comp); OCtyp : constant Entity_Id := Etype (Ocomp); Ind : Node_Id; Indtyp : Entity_Id; Lo, Hi : Node_Id; begin Ind := First_Index (OCtyp); while Present (Ind) loop Indtyp := Etype (Ind); if Is_Enumeration_Type (Indtyp) and then Has_Non_Standard_Rep (Indtyp) then Lo := Type_Low_Bound (Indtyp); Hi := Type_High_Bound (Indtyp); if Is_Entity_Name (Lo) and then Ekind (Entity (Lo)) = E_Discriminant then return False; elsif Is_Entity_Name (Hi) and then Ekind (Entity (Hi)) = E_Discriminant then return False; end if; end if; Next_Index (Ind); end loop; end; end if; -- Clearly size of record is not known if the size of -- one of the components is not known. if not Size_Known (Ctyp) then return False; end if; -- Accumulate packed size if possible if Packed_Size_Known then -- We can only deal with elementary types, since for -- non-elementary components, alignment enters into -- the picture, and we don't know enough to handle -- proper alignment in this context. Packed arrays -- count as elementary if the representation is a -- modular type. if Is_Elementary_Type (Ctyp) or else (Is_Array_Type (Ctyp) and then Present (Packed_Array_Type (Ctyp)) and then Is_Modular_Integer_Type (Packed_Array_Type (Ctyp))) then -- If RM_Size is known and static, then we can -- keep accumulating the packed size. if Known_Static_RM_Size (Ctyp) then -- A little glitch, to be removed sometime ??? -- gigi does not understand zero sizes yet. if RM_Size (Ctyp) = Uint_0 then Packed_Size_Known := False; -- Normal case where we can keep accumulating -- the packed array size. else Packed_Size := Packed_Size + RM_Size (Ctyp); end if; -- If we have a field whose RM_Size is not known -- then we can't figure out the packed size here. else Packed_Size_Known := False; end if; -- If we have a non-elementary type we can't figure -- out the packed array size (alignment issues). else Packed_Size_Known := False; end if; end if; end if; Next_Entity (Comp); end loop; if Packed_Size_Known then Set_Small_Size (T, Packed_Size); end if; return True; end; else return False; end if; end Size_Known; ------------------------------------- -- Static_Discriminated_Components -- ------------------------------------- function Static_Discriminated_Components (T : Entity_Id) return Boolean is Constraint : Elmt_Id; Discr : Entity_Id; begin if Has_Discriminants (T) and then Present (Discriminant_Constraint (T)) and then Present (First_Component (T)) then Discr := First_Discriminant (T); if Is_Access_Type (Etype (Discr)) then null; -- If the bounds of the discriminant are not compile-time known, -- treat this as non-static, even if the value of the discriminant -- is compile-time known, because the back-end treats aggregates -- of such a subtype as having unknown size. elsif not (Compile_Time_Known_Value (Type_Low_Bound (Etype (Discr))) and then Compile_Time_Known_Value (Type_High_Bound (Etype (Discr)))) then return False; end if; Constraint := First_Elmt (Discriminant_Constraint (T)); while Present (Constraint) loop if not Compile_Time_Known_Value (Node (Constraint)) then return False; end if; Next_Elmt (Constraint); end loop; end if; return True; end Static_Discriminated_Components; -- Start of processing for Check_Compile_Time_Size begin Set_Size_Known_At_Compile_Time (T, Size_Known (T)); end Check_Compile_Time_Size; ----------------------------- -- Check_Debug_Info_Needed -- ----------------------------- procedure Check_Debug_Info_Needed (T : Entity_Id) is begin if Needs_Debug_Info (T) or else Debug_Info_Off (T) then return; elsif Comes_From_Source (T) or else Debug_Generated_Code or else Debug_Flag_VV then Set_Debug_Info_Needed (T); end if; end Check_Debug_Info_Needed; ---------------------------- -- Check_Strict_Alignment -- ---------------------------- procedure Check_Strict_Alignment (E : Entity_Id) is Comp : Entity_Id; begin if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then Set_Strict_Alignment (E); elsif Is_Array_Type (E) then Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E))); elsif Is_Record_Type (E) then if Is_Limited_Record (E) then Set_Strict_Alignment (E); return; end if; Comp := First_Component (E); while Present (Comp) loop if not Is_Type (Comp) and then (Strict_Alignment (Etype (Comp)) or else Is_Aliased (Comp)) then Set_Strict_Alignment (E); return; end if; Next_Component (Comp); end loop; end if; end Check_Strict_Alignment; ------------------------- -- Check_Unsigned_Type -- ------------------------- procedure Check_Unsigned_Type (E : Entity_Id) is Ancestor : Entity_Id; Lo_Bound : Node_Id; Btyp : Entity_Id; begin if not Is_Discrete_Or_Fixed_Point_Type (E) then return; end if; -- Do not attempt to analyze case where range was in error if Error_Posted (Scalar_Range (E)) then return; end if; -- The situation that is non trivial is something like -- subtype x1 is integer range -10 .. +10; -- subtype x2 is x1 range 0 .. V1; -- subtype x3 is x2 range V2 .. V3; -- subtype x4 is x3 range V4 .. V5; -- where Vn are variables. Here the base type is signed, but we still -- know that x4 is unsigned because of the lower bound of x2. -- The only way to deal with this is to look up the ancestor chain Ancestor := E; loop if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then return; end if; Lo_Bound := Type_Low_Bound (Ancestor); if Compile_Time_Known_Value (Lo_Bound) then if Expr_Rep_Value (Lo_Bound) >= 0 then Set_Is_Unsigned_Type (E, True); end if; return; else Ancestor := Ancestor_Subtype (Ancestor); -- If no ancestor had a static lower bound, go to base type if No (Ancestor) then -- Note: the reason we still check for a compile time known -- value for the base type is that at least in the case of -- generic formals, we can have bounds that fail this test, -- and there may be other cases in error situations. Btyp := Base_Type (E); if Btyp = Any_Type or else Etype (Btyp) = Any_Type then return; end if; Lo_Bound := Type_Low_Bound (Base_Type (E)); if Compile_Time_Known_Value (Lo_Bound) and then Expr_Rep_Value (Lo_Bound) >= 0 then Set_Is_Unsigned_Type (E, True); end if; return; end if; end if; end loop; end Check_Unsigned_Type; ----------------------------- -- Expand_Atomic_Aggregate -- ----------------------------- procedure Expand_Atomic_Aggregate (E : Entity_Id; Typ : Entity_Id) is Loc : constant Source_Ptr := Sloc (E); New_N : Node_Id; Temp : Entity_Id; begin if (Nkind (Parent (E)) = N_Object_Declaration or else Nkind (Parent (E)) = N_Assignment_Statement) and then Comes_From_Source (Parent (E)) and then Nkind (E) = N_Aggregate then Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('T')); New_N := Make_Object_Declaration (Loc, Defining_Identifier => Temp, -- LLVM local Object_Definition => New_Occurrence_Of (Typ, Loc), Expression => Relocate_Node (E)); Insert_Before (Parent (E), New_N); Analyze (New_N); Set_Expression (Parent (E), New_Occurrence_Of (Temp, Loc)); -- To prevent the temporary from being constant-folded (which -- would lead to the same piecemeal assignment on the original -- target) indicate to the back-end that the temporary is a -- variable with real storage. See description of this flag -- in Einfo, and the notes on N_Assignment_Statement and -- N_Object_Declaration in Sinfo. Set_Is_True_Constant (Temp, False); end if; end Expand_Atomic_Aggregate; ---------------- -- Freeze_All -- ---------------- -- Note: the easy coding for this procedure would be to just build a -- single list of freeze nodes and then insert them and analyze them -- all at once. This won't work, because the analysis of earlier freeze -- nodes may recursively freeze types which would otherwise appear later -- on in the freeze list. So we must analyze and expand the freeze nodes -- as they are generated. procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is Loc : constant Source_Ptr := Sloc (After); E : Entity_Id; Decl : Node_Id; procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id); -- This is the internal recursive routine that does freezing of -- entities (but NOT the analysis of default expressions, which -- should not be recursive, we don't want to analyze those till -- we are sure that ALL the types are frozen). -------------------- -- Freeze_All_Ent -- -------------------- procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is E : Entity_Id; Flist : List_Id; Lastn : Node_Id; procedure Process_Flist; -- If freeze nodes are present, insert and analyze, and reset -- cursor for next insertion. ------------------- -- Process_Flist -- ------------------- procedure Process_Flist is begin if Is_Non_Empty_List (Flist) then Lastn := Next (After); Insert_List_After_And_Analyze (After, Flist); if Present (Lastn) then After := Prev (Lastn); else After := Last (List_Containing (After)); end if; end if; end Process_Flist; -- Start or processing for Freeze_All_Ent begin E := From; while Present (E) loop -- If the entity is an inner package which is not a package -- renaming, then its entities must be frozen at this point. -- Note that such entities do NOT get frozen at the end of -- the nested package itself (only library packages freeze). -- Same is true for task declarations, where anonymous records -- created for entry parameters must be frozen. if Ekind (E) = E_Package and then No (Renamed_Object (E)) and then not Is_Child_Unit (E) and then not Is_Frozen (E) then New_Scope (E); Install_Visible_Declarations (E); Install_Private_Declarations (E); Freeze_All (First_Entity (E), After); End_Package_Scope (E); elsif Ekind (E) in Task_Kind and then (Nkind (Parent (E)) = N_Task_Type_Declaration or else Nkind (Parent (E)) = N_Single_Task_Declaration) then New_Scope (E); Freeze_All (First_Entity (E), After); End_Scope; -- For a derived tagged type, we must ensure that all the -- primitive operations of the parent have been frozen, so -- that their addresses will be in the parent's dispatch table -- at the point it is inherited. elsif Ekind (E) = E_Record_Type and then Is_Tagged_Type (E) and then Is_Tagged_Type (Etype (E)) and then Is_Derived_Type (E) then declare Prim_List : constant Elist_Id := Primitive_Operations (Etype (E)); Prim : Elmt_Id; Subp : Entity_Id; begin Prim := First_Elmt (Prim_List); while Present (Prim) loop Subp := Node (Prim); if Comes_From_Source (Subp) and then not Is_Frozen (Subp) then Flist := Freeze_Entity (Subp, Loc); Process_Flist; end if; Next_Elmt (Prim); end loop; end; end if; if not Is_Frozen (E) then Flist := Freeze_Entity (E, Loc); Process_Flist; end if; -- If an incomplete type is still not frozen, this may be -- a premature freezing because of a body declaration that -- follows. Indicate where the freezing took place. -- If the freezing is caused by the end of the current -- declarative part, it is a Taft Amendment type, and there -- is no error. if not Is_Frozen (E) and then Ekind (E) = E_Incomplete_Type then declare Bod : constant Node_Id := Next (After); begin if (Nkind (Bod) = N_Subprogram_Body or else Nkind (Bod) = N_Entry_Body or else Nkind (Bod) = N_Package_Body or else Nkind (Bod) = N_Protected_Body or else Nkind (Bod) = N_Task_Body or else Nkind (Bod) in N_Body_Stub) and then List_Containing (After) = List_Containing (Parent (E)) then Error_Msg_Sloc := Sloc (Next (After)); Error_Msg_NE ("type& is frozen# before its full declaration", Parent (E), E); end if; end; end if; Next_Entity (E); end loop; end Freeze_All_Ent; -- Start of processing for Freeze_All begin Freeze_All_Ent (From, After); -- Now that all types are frozen, we can deal with default expressions -- that require us to build a default expression functions. This is the -- point at which such functions are constructed (after all types that -- might be used in such expressions have been frozen). -- We also add finalization chains to access types whose designated -- types are controlled. This is normally done when freezing the type, -- but this misses recursive type definitions where the later members -- of the recursion introduce controlled components (e.g. 5624-001). -- Loop through entities E := From; while Present (E) loop if Is_Subprogram (E) then if not Default_Expressions_Processed (E) then Process_Default_Expressions (E, After); end if; if not Has_Completion (E) then Decl := Unit_Declaration_Node (E); if Nkind (Decl) = N_Subprogram_Renaming_Declaration then Build_And_Analyze_Renamed_Body (Decl, E, After); elsif Nkind (Decl) = N_Subprogram_Declaration and then Present (Corresponding_Body (Decl)) and then Nkind (Unit_Declaration_Node (Corresponding_Body (Decl))) = N_Subprogram_Renaming_Declaration then Build_And_Analyze_Renamed_Body (Decl, Corresponding_Body (Decl), After); end if; end if; elsif Ekind (E) in Task_Kind and then (Nkind (Parent (E)) = N_Task_Type_Declaration or else Nkind (Parent (E)) = N_Single_Task_Declaration) then declare Ent : Entity_Id; begin Ent := First_Entity (E); while Present (Ent) loop if Is_Entry (Ent) and then not Default_Expressions_Processed (Ent) then Process_Default_Expressions (Ent, After); end if; Next_Entity (Ent); end loop; end; elsif Is_Access_Type (E) and then Comes_From_Source (E) and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type and then Controlled_Type (Designated_Type (E)) and then No (Associated_Final_Chain (E)) then Build_Final_List (Parent (E), E); end if; Next_Entity (E); end loop; end Freeze_All; ----------------------- -- Freeze_And_Append -- ----------------------- procedure Freeze_And_Append (Ent : Entity_Id; Loc : Source_Ptr; Result : in out List_Id) is L : constant List_Id := Freeze_Entity (Ent, Loc); begin if Is_Non_Empty_List (L) then if Result = No_List then Result := L; else Append_List (L, Result); end if; end if; end Freeze_And_Append; ------------------- -- Freeze_Before -- ------------------- procedure Freeze_Before (N : Node_Id; T : Entity_Id) is Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N)); begin if Is_Non_Empty_List (Freeze_Nodes) then Insert_Actions (N, Freeze_Nodes); end if; end Freeze_Before; ------------------- -- Freeze_Entity -- ------------------- function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is Test_E : Entity_Id := E; Comp : Entity_Id; F_Node : Node_Id; Result : List_Id; Indx : Node_Id; Formal : Entity_Id; Atype : Entity_Id; procedure Check_Current_Instance (Comp_Decl : Node_Id); -- Check that an Access or Unchecked_Access attribute with a prefix -- which is the current instance type can only be applied when the type -- is limited. function After_Last_Declaration return Boolean; -- If Loc is a freeze_entity that appears after the last declaration -- in the scope, inhibit error messages on late completion. procedure Freeze_Record_Type (Rec : Entity_Id); -- Freeze each component, handle some representation clauses, and freeze -- primitive operations if this is a tagged type. ---------------------------- -- After_Last_Declaration -- ---------------------------- function After_Last_Declaration return Boolean is Spec : constant Node_Id := Parent (Current_Scope); begin if Nkind (Spec) = N_Package_Specification then if Present (Private_Declarations (Spec)) then return Loc >= Sloc (Last (Private_Declarations (Spec))); elsif Present (Visible_Declarations (Spec)) then return Loc >= Sloc (Last (Visible_Declarations (Spec))); else return False; end if; else return False; end if; end After_Last_Declaration; ---------------------------- -- Check_Current_Instance -- ---------------------------- procedure Check_Current_Instance (Comp_Decl : Node_Id) is function Process (N : Node_Id) return Traverse_Result; -- Process routine to apply check to given node ------------- -- Process -- ------------- function Process (N : Node_Id) return Traverse_Result is begin case Nkind (N) is when N_Attribute_Reference => if (Attribute_Name (N) = Name_Access or else Attribute_Name (N) = Name_Unchecked_Access) and then Is_Entity_Name (Prefix (N)) and then Is_Type (Entity (Prefix (N))) and then Entity (Prefix (N)) = E then Error_Msg_N ("current instance must be a limited type", Prefix (N)); return Abandon; else return OK; end if; when others => return OK; end case; end Process; procedure Traverse is new Traverse_Proc (Process); -- Start of processing for Check_Current_Instance begin Traverse (Comp_Decl); end Check_Current_Instance; ------------------------ -- Freeze_Record_Type -- ------------------------ procedure Freeze_Record_Type (Rec : Entity_Id) is Comp : Entity_Id; IR : Node_Id; Junk : Boolean; ADC : Node_Id; Prev : Entity_Id; Unplaced_Component : Boolean := False; -- Set True if we find at least one component with no component -- clause (used to warn about useless Pack pragmas). Placed_Component : Boolean := False; -- Set True if we find at least one component with a component -- clause (used to warn about useless Bit_Order pragmas). procedure Check_Itype (Desig : Entity_Id); -- If the component subtype is an access to a constrained subtype -- of an already frozen type, make the subtype frozen as well. It -- might otherwise be frozen in the wrong scope, and a freeze node -- on subtype has no effect. ----------------- -- Check_Itype -- ----------------- procedure Check_Itype (Desig : Entity_Id) is begin if not Is_Frozen (Desig) and then Is_Frozen (Base_Type (Desig)) then Set_Is_Frozen (Desig); -- In addition, add an Itype_Reference to ensure that the -- access subtype is elaborated early enough. This cannot -- be done if the subtype may depend on discriminants. if Ekind (Comp) = E_Component and then Is_Itype (Etype (Comp)) and then not Has_Discriminants (Rec) then IR := Make_Itype_Reference (Sloc (Comp)); Set_Itype (IR, Desig); if No (Result) then Result := New_List (IR); else Append (IR, Result); end if; end if; end if; end Check_Itype; -- Start of processing for Freeze_Record_Type begin -- If this is a subtype of a controlled type, declared without -- a constraint, the _controller may not appear in the component -- list if the parent was not frozen at the point of subtype -- declaration. Inherit the _controller component now. if Rec /= Base_Type (Rec) and then Has_Controlled_Component (Rec) then if Nkind (Parent (Rec)) = N_Subtype_Declaration and then Is_Entity_Name (Subtype_Indication (Parent (Rec))) then Set_First_Entity (Rec, First_Entity (Base_Type (Rec))); -- If this is an internal type without a declaration, as for -- record component, the base type may not yet be frozen, and its -- controller has not been created. Add an explicit freeze node -- for the itype, so it will be frozen after the base type. This -- freeze node is used to communicate with the expander, in order -- to create the controller for the enclosing record, and it is -- deleted afterwards (see exp_ch3). It must not be created when -- expansion is off, because it might appear in the wrong context -- for the back end. elsif Is_Itype (Rec) and then Has_Delayed_Freeze (Base_Type (Rec)) and then Nkind (Associated_Node_For_Itype (Rec)) = N_Component_Declaration and then Expander_Active then Ensure_Freeze_Node (Rec); end if; end if; -- Freeze components and embedded subtypes Comp := First_Entity (Rec); Prev := Empty; while Present (Comp) loop -- First handle the (real) component case if Ekind (Comp) = E_Component or else Ekind (Comp) = E_Discriminant then declare CC : constant Node_Id := Component_Clause (Comp); begin -- Freezing a record type freezes the type of each of its -- components. However, if the type of the component is -- part of this record, we do not want or need a separate -- Freeze_Node. Note that Is_Itype is wrong because that's -- also set in private type cases. We also can't check for -- the Scope being exactly Rec because of private types and -- record extensions. if Is_Itype (Etype (Comp)) and then Is_Record_Type (Underlying_Type (Scope (Etype (Comp)))) then Undelay_Type (Etype (Comp)); end if; Freeze_And_Append (Etype (Comp), Loc, Result); -- Check for error of component clause given for variable -- sized type. We have to delay this test till this point, -- since the component type has to be frozen for us to know -- if it is variable length. We omit this test in a generic -- context, it will be applied at instantiation time. if Present (CC) then Placed_Component := True; if Inside_A_Generic then null; elsif not Size_Known_At_Compile_Time (Underlying_Type (Etype (Comp))) then Error_Msg_N ("component clause not allowed for variable " & "length component", CC); end if; else Unplaced_Component := True; end if; -- Case of component requires byte alignment if Must_Be_On_Byte_Boundary (Etype (Comp)) then -- Set the enclosing record to also require byte align Set_Must_Be_On_Byte_Boundary (Rec); -- Check for component clause that is inconsistent -- with the required byte boundary alignment. if Present (CC) and then Normalized_First_Bit (Comp) mod System_Storage_Unit /= 0 then Error_Msg_N ("component & must be byte aligned", Component_Name (Component_Clause (Comp))); end if; end if; -- If component clause is present, then deal with the -- non-default bit order case. We cannot do this before -- the freeze point, because there is no required order -- for the component clause and the bit_order clause. -- We only do this processing for the base type, and in -- fact that's important, since otherwise if there are -- record subtypes, we could reverse the bits once for -- each subtype, which would be incorrect. if Present (CC) and then Reverse_Bit_Order (Rec) and then Ekind (E) = E_Record_Type then declare CFB : constant Uint := Component_Bit_Offset (Comp); CSZ : constant Uint := Esize (Comp); CLC : constant Node_Id := Component_Clause (Comp); Pos : constant Node_Id := Position (CLC); FB : constant Node_Id := First_Bit (CLC); Storage_Unit_Offset : constant Uint := CFB / System_Storage_Unit; Start_Bit : constant Uint := CFB mod System_Storage_Unit; begin -- Cases where field goes over storage unit boundary if Start_Bit + CSZ > System_Storage_Unit then -- Allow multi-byte field but generate warning if Start_Bit mod System_Storage_Unit = 0 and then CSZ mod System_Storage_Unit = 0 then Error_Msg_N ("multi-byte field specified with non-standard" & " Bit_Order?", CLC); if Bytes_Big_Endian then Error_Msg_N ("bytes are not reversed " & "(component is big-endian)?", CLC); else Error_Msg_N ("bytes are not reversed " & "(component is little-endian)?", CLC); end if; -- Do not allow non-contiguous field else Error_Msg_N ("attempt to specify non-contiguous field" & " not permitted", CLC); Error_Msg_N ("\(caused by non-standard Bit_Order " & "specified)", CLC); end if; -- Case where field fits in one storage unit else -- Give warning if suspicious component clause if Intval (FB) >= System_Storage_Unit then Error_Msg_N ("?Bit_Order clause does not affect " & "byte ordering", Pos); Error_Msg_Uint_1 := Intval (Pos) + Intval (FB) / System_Storage_Unit; Error_Msg_N ("?position normalized to ^ before bit " & "order interpreted", Pos); end if; -- Here is where we fix up the Component_Bit_Offset -- value to account for the reverse bit order. -- Some examples of what needs to be done are: -- First_Bit .. Last_Bit Component_Bit_Offset -- old new old new -- 0 .. 0 7 .. 7 0 7 -- 0 .. 1 6 .. 7 0 6 -- 0 .. 2 5 .. 7 0 5 -- 0 .. 7 0 .. 7 0 4 -- 1 .. 1 6 .. 6 1 6 -- 1 .. 4 3 .. 6 1 3 -- 4 .. 7 0 .. 3 4 0 -- The general rule is that the first bit is -- is obtained by subtracting the old ending bit -- from storage_unit - 1. Set_Component_Bit_Offset (Comp, (Storage_Unit_Offset * System_Storage_Unit) + (System_Storage_Unit - 1) - (Start_Bit + CSZ - 1)); Set_Normalized_First_Bit (Comp, Component_Bit_Offset (Comp) mod System_Storage_Unit); end if; end; end if; end; end if; -- If the component is an Itype with Delayed_Freeze and is either -- a record or array subtype and its base type has not yet been -- frozen, we must remove this from the entity list of this -- record and put it on the entity list of the scope of its base -- type. Note that we know that this is not the type of a -- component since we cleared Has_Delayed_Freeze for it in the -- previous loop. Thus this must be the Designated_Type of an -- access type, which is the type of a component. if Is_Itype (Comp) and then Is_Type (Scope (Comp)) and then Is_Composite_Type (Comp) and then Base_Type (Comp) /= Comp and then Has_Delayed_Freeze (Comp) and then not Is_Frozen (Base_Type (Comp)) then declare Will_Be_Frozen : Boolean := False; S : Entity_Id := Scope (Rec); begin -- We have a pretty bad kludge here. Suppose Rec is a -- subtype being defined in a subprogram that's created -- as part of the freezing of Rec'Base. In that case, -- we know that Comp'Base must have already been frozen by -- the time we get to elaborate this because Gigi doesn't -- elaborate any bodies until it has elaborated all of the -- declarative part. But Is_Frozen will not be set at this -- point because we are processing code in lexical order. -- We detect this case by going up the Scope chain of -- Rec and seeing if we have a subprogram scope before -- reaching the top of the scope chain or that of Comp'Base. -- If we do, then mark that Comp'Base will actually be -- frozen. If so, we merely undelay it. while Present (S) loop if Is_Subprogram (S) then Will_Be_Frozen := True; exit; elsif S = Scope (Base_Type (Comp)) then exit; end if; S := Scope (S); end loop; if Will_Be_Frozen then Undelay_Type (Comp); else if Present (Prev) then Set_Next_Entity (Prev, Next_Entity (Comp)); else Set_First_Entity (Rec, Next_Entity (Comp)); end if; -- Insert in entity list of scope of base type (which -- must be an enclosing scope, because still unfrozen). Append_Entity (Comp, Scope (Base_Type (Comp))); end if; end; -- If the component is an access type with an allocator as -- default value, the designated type will be frozen by the -- corresponding expression in init_proc. In order to place the -- freeze node for the designated type before that for the -- current record type, freeze it now. -- Same process if the component is an array of access types, -- initialized with an aggregate. If the designated type is -- private, it cannot contain allocators, and it is premature to -- freeze the type, so we check for this as well. elsif Is_Access_Type (Etype (Comp)) and then Present (Parent (Comp)) and then Present (Expression (Parent (Comp))) and then Nkind (Expression (Parent (Comp))) = N_Allocator then declare Alloc : constant Node_Id := Expression (Parent (Comp)); begin -- If component is pointer to a classwide type, freeze -- the specific type in the expression being allocated. -- The expression may be a subtype indication, in which -- case freeze the subtype mark. if Is_Class_Wide_Type (Designated_Type (Etype (Comp))) then if Is_Entity_Name (Expression (Alloc)) then Freeze_And_Append (Entity (Expression (Alloc)), Loc, Result); elsif Nkind (Expression (Alloc)) = N_Subtype_Indication then Freeze_And_Append (Entity (Subtype_Mark (Expression (Alloc))), Loc, Result); end if; elsif Is_Itype (Designated_Type (Etype (Comp))) then Check_Itype (Designated_Type (Etype (Comp))); else Freeze_And_Append (Designated_Type (Etype (Comp)), Loc, Result); end if; end; elsif Is_Access_Type (Etype (Comp)) and then Is_Itype (Designated_Type (Etype (Comp))) then Check_Itype (Designated_Type (Etype (Comp))); elsif Is_Array_Type (Etype (Comp)) and then Is_Access_Type (Component_Type (Etype (Comp))) and then Present (Parent (Comp)) and then Nkind (Parent (Comp)) = N_Component_Declaration and then Present (Expression (Parent (Comp))) and then Nkind (Expression (Parent (Comp))) = N_Aggregate and then Is_Fully_Defined (Designated_Type (Component_Type (Etype (Comp)))) then Freeze_And_Append (Designated_Type (Component_Type (Etype (Comp))), Loc, Result); end if; Prev := Comp; Next_Entity (Comp); end loop; -- Check for useless pragma Bit_Order if not Placed_Component and then Reverse_Bit_Order (Rec) then ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order); Error_Msg_N ("?Bit_Order specification has no effect", ADC); Error_Msg_N ("\?since no component clauses were specified", ADC); end if; -- Check for useless pragma Pack when all components placed. We only -- do this check for record types, not subtypes, since a subtype may -- have all its components placed, and it still makes perfectly good -- sense to pack other subtypes or the parent type. if Ekind (Rec) = E_Record_Type and then Is_Packed (Rec) and then not Unplaced_Component then -- Reset packed status. Probably not necessary, but we do it -- so that there is no chance of the back end doing something -- strange with this redundant indication of packing. Set_Is_Packed (Rec, False); -- Give warning if redundant constructs warnings on if Warn_On_Redundant_Constructs then Error_Msg_N ("?pragma Pack has no effect, no unplaced components", Get_Rep_Pragma (Rec, Name_Pack)); end if; end if; -- If this is the record corresponding to a remote type, freeze the -- remote type here since that is what we are semantically freezing. -- This prevents the freeze node for that type in an inner scope. -- Also, Check for controlled components and unchecked unions. -- Finally, enforce the restriction that access attributes with a -- current instance prefix can only apply to limited types. if Ekind (Rec) = E_Record_Type then if Present (Corresponding_Remote_Type (Rec)) then Freeze_And_Append (Corresponding_Remote_Type (Rec), Loc, Result); end if; Comp := First_Component (Rec); while Present (Comp) loop if Has_Controlled_Component (Etype (Comp)) or else (Chars (Comp) /= Name_uParent and then Is_Controlled (Etype (Comp))) or else (Is_Protected_Type (Etype (Comp)) and then Present (Corresponding_Record_Type (Etype (Comp))) and then Has_Controlled_Component (Corresponding_Record_Type (Etype (Comp)))) then Set_Has_Controlled_Component (Rec); exit; end if; if Has_Unchecked_Union (Etype (Comp)) then Set_Has_Unchecked_Union (Rec); end if; if Has_Per_Object_Constraint (Comp) and then not Is_Limited_Type (Rec) then -- Scan component declaration for likely misuses of current -- instance, either in a constraint or a default expression. Check_Current_Instance (Parent (Comp)); end if; Next_Component (Comp); end loop; end if; Set_Component_Alignment_If_Not_Set (Rec); -- For first subtypes, check if there are any fixed-point fields with -- component clauses, where we must check the size. This is not done -- till the freeze point, since for fixed-point types, we do not know -- the size until the type is frozen. Similar processing applies to -- bit packed arrays. if Is_First_Subtype (Rec) then Comp := First_Component (Rec); while Present (Comp) loop if Present (Component_Clause (Comp)) and then (Is_Fixed_Point_Type (Etype (Comp)) or else Is_Bit_Packed_Array (Etype (Comp))) then Check_Size (Component_Name (Component_Clause (Comp)), Etype (Comp), Esize (Comp), Junk); end if; Next_Component (Comp); end loop; end if; end Freeze_Record_Type; -- Start of processing for Freeze_Entity begin -- We are going to test for various reasons why this entity need not be -- frozen here, but in the case of an Itype that's defined within a -- record, that test actually applies to the record. if Is_Itype (E) and then Is_Record_Type (Scope (E)) then Test_E := Scope (E); elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E))) and then Is_Record_Type (Underlying_Type (Scope (E))) then Test_E := Underlying_Type (Scope (E)); end if; -- Do not freeze if already frozen since we only need one freeze node if Is_Frozen (E) then return No_List; -- It is improper to freeze an external entity within a generic because -- its freeze node will appear in a non-valid context. The entity will -- be frozen in the proper scope after the current generic is analyzed. elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then return No_List; -- Do not freeze a global entity within an inner scope created during -- expansion. A call to subprogram E within some internal procedure -- (a stream attribute for example) might require freezing E, but the -- freeze node must appear in the same declarative part as E itself. -- The two-pass elaboration mechanism in gigi guarantees that E will -- be frozen before the inner call is elaborated. We exclude constants -- from this test, because deferred constants may be frozen early, and -- must be diagnosed (see e.g. 1522-005). If the enclosing subprogram -- comes from source, or is a generic instance, then the freeze point -- is the one mandated by the language. and we freze the entity. elsif In_Open_Scopes (Scope (Test_E)) and then Scope (Test_E) /= Current_Scope and then Ekind (Test_E) /= E_Constant then declare S : Entity_Id := Current_Scope; begin while Present (S) loop if Is_Overloadable (S) then if Comes_From_Source (S) or else Is_Generic_Instance (S) then exit; else return No_List; end if; end if; S := Scope (S); end loop; end; -- Similarly, an inlined instance body may make reference to global -- entities, but these references cannot be the proper freezing point -- for them, and the the absence of inlining freezing will take place -- in their own scope. Normally instance bodies are analyzed after -- the enclosing compilation, and everything has been frozen at the -- proper place, but with front-end inlining an instance body is -- compiled before the end of the enclosing scope, and as a result -- out-of-order freezing must be prevented. elsif Front_End_Inlining and then In_Instance_Body and then Present (Scope (Test_E)) then declare S : Entity_Id := Scope (Test_E); begin while Present (S) loop if Is_Generic_Instance (S) then exit; else S := Scope (S); end if; end loop; if No (S) then return No_List; end if; end; end if; -- Here to freeze the entity Result := No_List; Set_Is_Frozen (E); -- Case of entity being frozen is other than a type if not Is_Type (E) then -- If entity is exported or imported and does not have an external -- name, now is the time to provide the appropriate default name. -- Skip this if the entity is stubbed, since we don't need a name -- for any stubbed routine. if (Is_Imported (E) or else Is_Exported (E)) and then No (Interface_Name (E)) and then Convention (E) /= Convention_Stubbed then Set_Encoded_Interface_Name (E, Get_Default_External_Name (E)); -- Special processing for atomic objects appearing in object decls elsif Is_Atomic (E) and then Nkind (Parent (E)) = N_Object_Declaration and then Present (Expression (Parent (E))) then declare Expr : constant Node_Id := Expression (Parent (E)); begin -- If expression is an aggregate, assign to a temporary to -- ensure that the actual assignment is done atomically rather -- than component-wise (the assignment to the temp may be done -- component-wise, but that is harmless. if Nkind (Expr) = N_Aggregate then Expand_Atomic_Aggregate (Expr, Etype (E)); -- If the expression is a reference to a record or array object -- entity, then reset Is_True_Constant to False so that the -- compiler will not optimize away the intermediate object, -- which we need in this case for the same reason (to ensure -- that the actual assignment is atomic, rather than -- component-wise). elsif Is_Entity_Name (Expr) and then (Is_Record_Type (Etype (Expr)) or else Is_Array_Type (Etype (Expr))) then Set_Is_True_Constant (Entity (Expr), False); end if; end; end if; -- For a subprogram, freeze all parameter types and also the return -- type (RM 13.14(14)). However skip this for internal subprograms. -- This is also the point where any extra formal parameters are -- created since we now know whether the subprogram will use -- a foreign convention. if Is_Subprogram (E) then if not Is_Internal (E) then declare F_Type : Entity_Id; Warn_Node : Node_Id; function Is_Fat_C_Ptr_Type (T : Entity_Id) return Boolean; -- Determines if given type entity is a fat pointer type -- used as an argument type or return type to a subprogram -- with C or C++ convention set. -------------------------- -- Is_Fat_C_Access_Type -- -------------------------- function Is_Fat_C_Ptr_Type (T : Entity_Id) return Boolean is begin return (Convention (E) = Convention_C or else Convention (E) = Convention_CPP) and then Is_Access_Type (T) and then Esize (T) > Ttypes.System_Address_Size; end Is_Fat_C_Ptr_Type; begin -- Loop through formals Formal := First_Formal (E); while Present (Formal) loop F_Type := Etype (Formal); Freeze_And_Append (F_Type, Loc, Result); if Is_Private_Type (F_Type) and then Is_Private_Type (Base_Type (F_Type)) and then No (Full_View (Base_Type (F_Type))) and then not Is_Generic_Type (F_Type) and then not Is_Derived_Type (F_Type) then -- If the type of a formal is incomplete, subprogram -- is being frozen prematurely. Within an instance -- (but not within a wrapper package) this is an -- an artifact of our need to regard the end of an -- instantiation as a freeze point. Otherwise it is -- a definite error. -- and then not Is_Wrapper_Package (Current_Scope) ??? if In_Instance then Set_Is_Frozen (E, False); return No_List; elsif not After_Last_Declaration then Error_Msg_Node_1 := F_Type; Error_Msg ("type& must be fully defined before this point", Loc); end if; end if; -- Check bad use of fat C pointer if Warn_On_Export_Import and then Is_Fat_C_Ptr_Type (F_Type) then Error_Msg_Qual_Level := 1; Error_Msg_N ("?type of & does not correspond to C pointer", Formal); Error_Msg_Qual_Level := 0; end if; -- Check for unconstrained array in exported foreign -- convention case. if Convention (E) in Foreign_Convention and then not Is_Imported (E) and then Is_Array_Type (F_Type) and then not Is_Constrained (F_Type) and then Warn_On_Export_Import then Error_Msg_Qual_Level := 1; -- If this is an inherited operation, place the -- warning on the derived type declaration, rather -- than on the original subprogram. if Nkind (Original_Node (Parent (E))) = N_Full_Type_Declaration then Warn_Node := Parent (E); if Formal = First_Formal (E) then Error_Msg_NE ("?in inherited operation&", Warn_Node, E); end if; else Warn_Node := Formal; end if; Error_Msg_NE ("?type of argument& is unconstrained array", Warn_Node, Formal); Error_Msg_NE ("?foreign caller must pass bounds explicitly", Warn_Node, Formal); Error_Msg_Qual_Level := 0; end if; -- Ada 2005 (AI-326): Check wrong use of tag incomplete -- types with unknown discriminants. For example: -- type T (<>) is tagged; -- procedure P (X : access T); -- ERROR -- procedure P (X : T); -- ERROR if not From_With_Type (F_Type) then if Is_Access_Type (F_Type) then F_Type := Designated_Type (F_Type); end if; if Ekind (F_Type) = E_Incomplete_Type and then Is_Tagged_Type (F_Type) and then not Is_Class_Wide_Type (F_Type) and then No (Full_View (F_Type)) and then Unknown_Discriminants_Present (Parent (F_Type)) and then No (Stored_Constraint (F_Type)) then Error_Msg_N ("(Ada 2005): invalid use of unconstrained tagged" & " incomplete type", E); elsif Ekind (F_Type) = E_Subprogram_Type then Freeze_And_Append (F_Type, Loc, Result); end if; end if; Next_Formal (Formal); end loop; -- Check return type if Ekind (E) = E_Function then Freeze_And_Append (Etype (E), Loc, Result); if Warn_On_Export_Import and then Is_Fat_C_Ptr_Type (Etype (E)) then Error_Msg_N ("?return type of& does not correspond to C pointer", E); elsif Is_Array_Type (Etype (E)) and then not Is_Constrained (Etype (E)) and then not Is_Imported (E) and then Convention (E) in Foreign_Convention and then Warn_On_Export_Import then Error_Msg_N ("?foreign convention function& should not " & "return unconstrained array", E); -- Ada 2005 (AI-326): Check wrong use of tagged -- incomplete type -- -- type T is tagged; -- function F (X : Boolean) return T; -- ERROR elsif Ekind (Etype (E)) = E_Incomplete_Type and then Is_Tagged_Type (Etype (E)) and then No (Full_View (Etype (E))) then Error_Msg_N ("(Ada 2005): invalid use of tagged incomplete type", E); end if; end if; end; end if; -- Must freeze its parent first if it is a derived subprogram if Present (Alias (E)) then Freeze_And_Append (Alias (E), Loc, Result); end if; -- If the return type requires a transient scope, and we are on -- a target allowing functions to return with a depressed stack -- pointer, then we mark the function as requiring this treatment. if Ekind (E) = E_Function and then Functions_Return_By_DSP_On_Target and then Requires_Transient_Scope (Etype (E)) then Set_Function_Returns_With_DSP (E); end if; if not Is_Internal (E) then Freeze_Subprogram (E); end if; -- Here for other than a subprogram or type else -- If entity has a type, and it is not a generic unit, then -- freeze it first (RM 13.14(10)) if Present (Etype (E)) and then Ekind (E) /= E_Generic_Function then Freeze_And_Append (Etype (E), Loc, Result); end if; -- Special processing for objects created by object declaration if Nkind (Declaration_Node (E)) = N_Object_Declaration then -- For object created by object declaration, perform required -- categorization (preelaborate and pure) checks. Defer these -- checks to freeze time since pragma Import inhibits default -- initialization and thus pragma Import affects these checks. Validate_Object_Declaration (Declaration_Node (E)); -- If there is an address clause, check it is valid Check_Address_Clause (E); -- For imported objects, set Is_Public unless there is also -- an address clause, which means that there is no external -- symbol needed for the Import (Is_Public may still be set -- for other unrelated reasons). Note that we delayed this -- processing till freeze time so that we can be sure not -- to set the flag if there is an address clause. If there -- is such a clause, then the only purpose of the import -- pragma is to suppress implicit initialization. if Is_Imported (E) and then No (Address_Clause (E)) then Set_Is_Public (E); end if; end if; -- Check that a constant which has a pragma Volatile[_Components] -- or Atomic[_Components] also has a pragma Import (RM C.6(13)) -- Note: Atomic[_Components] also sets Volatile[_Components] if Ekind (E) = E_Constant and then (Has_Volatile_Components (E) or else Is_Volatile (E)) and then not Is_Imported (E) then -- Make sure we actually have a pragma, and have not merely -- inherited the indication from elsewhere (e.g. an address -- clause, which is not good enough in RM terms!) if Has_Rep_Pragma (E, Name_Atomic) or else Has_Rep_Pragma (E, Name_Atomic_Components) then Error_Msg_N ("stand alone atomic constant must be " & "imported ('R'M 'C.6(13))", E); elsif Has_Rep_Pragma (E, Name_Volatile) or else Has_Rep_Pragma (E, Name_Volatile_Components) then Error_Msg_N ("stand alone volatile constant must be " & "imported ('R'M 'C.6(13))", E); end if; end if; -- Static objects require special handling if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable) and then Is_Statically_Allocated (E) then Freeze_Static_Object (E); end if; -- Remaining step is to layout objects if Ekind (E) = E_Variable or else Ekind (E) = E_Constant or else Ekind (E) = E_Loop_Parameter or else Is_Formal (E) then Layout_Object (E); end if; end if; -- Case of a type or subtype being frozen else -- The type may be defined in a generic unit. This can occur when -- freezing a generic function that returns the type (which is -- defined in a parent unit). It is clearly meaningless to freeze -- this type. However, if it is a subtype, its size may be determi- -- nable and used in subsequent checks, so might as well try to -- compute it. if Present (Scope (E)) and then Is_Generic_Unit (Scope (E)) then Check_Compile_Time_Size (E); return No_List; end if; -- Deal with special cases of freezing for subtype if E /= Base_Type (E) then -- If ancestor subtype present, freeze that first. -- Note that this will also get the base type frozen. Atype := Ancestor_Subtype (E); if Present (Atype) then Freeze_And_Append (Atype, Loc, Result); -- Otherwise freeze the base type of the entity before -- freezing the entity itself, (RM 13.14(15)). elsif E /= Base_Type (E) then Freeze_And_Append (Base_Type (E), Loc, Result); end if; -- For a derived type, freeze its parent type first (RM 13.14(15)) elsif Is_Derived_Type (E) then Freeze_And_Append (Etype (E), Loc, Result); Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result); end if; -- For array type, freeze index types and component type first -- before freezing the array (RM 13.14(15)). if Is_Array_Type (E) then declare Ctyp : constant Entity_Id := Component_Type (E); Pnod : Node_Id; Non_Standard_Enum : Boolean := False; -- Set true if any of the index types is an enumeration -- type with a non-standard representation. begin Freeze_And_Append (Ctyp, Loc, Result); Indx := First_Index (E); while Present (Indx) loop Freeze_And_Append (Etype (Indx), Loc, Result); if Is_Enumeration_Type (Etype (Indx)) and then Has_Non_Standard_Rep (Etype (Indx)) then Non_Standard_Enum := True; end if; Next_Index (Indx); end loop; -- Processing that is done only for base types if Ekind (E) = E_Array_Type then -- Propagate flags for component type if Is_Controlled (Component_Type (E)) or else Has_Controlled_Component (Ctyp) then Set_Has_Controlled_Component (E); end if; if Has_Unchecked_Union (Component_Type (E)) then Set_Has_Unchecked_Union (E); end if; -- If packing was requested or if the component size was set -- explicitly, then see if bit packing is required. This -- processing is only done for base types, since all the -- representation aspects involved are type-related. This -- is not just an optimization, if we start processing the -- subtypes, they intefere with the settings on the base -- type (this is because Is_Packed has a slightly different -- meaning before and after freezing). declare Csiz : Uint; Esiz : Uint; begin if (Is_Packed (E) or else Has_Pragma_Pack (E)) and then not Has_Atomic_Components (E) and then Known_Static_RM_Size (Ctyp) then Csiz := UI_Max (RM_Size (Ctyp), 1); elsif Known_Component_Size (E) then Csiz := Component_Size (E); elsif not Known_Static_Esize (Ctyp) then Csiz := Uint_0; else Esiz := Esize (Ctyp); -- We can set the component size if it is less than -- 16, rounding it up to the next storage unit size. if Esiz <= 8 then Csiz := Uint_8; elsif Esiz <= 16 then Csiz := Uint_16; else Csiz := Uint_0; end if; -- Set component size up to match alignment if -- it would otherwise be less than the alignment. -- This deals with cases of types whose alignment -- exceeds their sizes (padded types). if Csiz /= 0 then declare A : constant Uint := Alignment_In_Bits (Ctyp); begin if Csiz < A then Csiz := A; end if; end; end if; end if; if 1 <= Csiz and then Csiz <= 64 then -- We set the component size for all cases 1-64 Set_Component_Size (Base_Type (E), Csiz); -- Check for base type of 8,16,32 bits, where the -- subtype has a length one less than the base type -- and is unsigned (e.g. Natural subtype of Integer) -- In such cases, if a component size was not set -- explicitly, then generate a warning. if Has_Pragma_Pack (E) and then not Has_Component_Size_Clause (E) and then (Csiz = 7 or else Csiz = 15 or else Csiz = 31) and then Esize (Base_Type (Ctyp)) = Csiz + 1 then Error_Msg_Uint_1 := Csiz; Pnod := Get_Rep_Pragma (First_Subtype (E), Name_Pack); if Present (Pnod) then Error_Msg_N ("pragma Pack causes component size to be ^?", Pnod); Error_Msg_N ("\use Component_Size to set desired value", Pnod); end if; end if; -- Actual packing is not needed for 8,16,32,64 -- Also not needed for 24 if alignment is 1 if Csiz = 8 or else Csiz = 16 or else Csiz = 32 or else Csiz = 64 or else (Csiz = 24 and then Alignment (Ctyp) = 1) then -- Here the array was requested to be packed, but -- the packing request had no effect, so Is_Packed -- is reset. -- Note: semantically this means that we lose -- track of the fact that a derived type inherited -- a pack pragma that was non-effective, but that -- seems fine. -- We regard a Pack pragma as a request to set a -- representation characteristic, and this request -- may be ignored. Set_Is_Packed (Base_Type (E), False); -- In all other cases, packing is indeed needed else Set_Has_Non_Standard_Rep (Base_Type (E)); Set_Is_Bit_Packed_Array (Base_Type (E)); Set_Is_Packed (Base_Type (E)); end if; end if; end; -- Processing that is done only for subtypes else -- Acquire alignment from base type if Unknown_Alignment (E) then Set_Alignment (E, Alignment (Base_Type (E))); end if; end if; -- For bit-packed arrays, check the size if Is_Bit_Packed_Array (E) and then Known_Esize (E) then declare Discard : Boolean; SizC : constant Node_Id := Size_Clause (E); begin -- It is not clear if it is possible to have no size -- clause at this stage, but this is not worth worrying -- about. Post the error on the entity name in the size -- clause if present, else on the type entity itself. if Present (SizC) then Check_Size (Name (SizC), E, Esize (E), Discard); else Check_Size (E, E, Esize (E), Discard); end if; end; end if; -- Check one common case of a size given where the array -- needs to be packed, but was not so the size cannot be -- honored. This would of course be caught by the backend, -- and indeed we don't catch all cases. The point is that -- we can give a better error message in those cases that -- we do catch with the circuitry here. declare Lo, Hi : Node_Id; Ctyp : constant Entity_Id := Component_Type (E); begin if Present (Size_Clause (E)) and then Known_Static_Esize (E) and then not Is_Bit_Packed_Array (E) and then not Has_Pragma_Pack (E) and then Number_Dimensions (E) = 1 and then not Has_Component_Size_Clause (E) and then Known_Static_Esize (Ctyp) then Get_Index_Bounds (First_Index (E), Lo, Hi); if Compile_Time_Known_Value (Lo) and then Compile_Time_Known_Value (Hi) and then Known_Static_RM_Size (Ctyp) and then RM_Size (Ctyp) < 64 then declare Lov : constant Uint := Expr_Value (Lo); Hiv : constant Uint := Expr_Value (Hi); Len : constant Uint := UI_Max (Uint_0, Hiv - Lov + 1); Rsiz : constant Uint := RM_Size (Ctyp); -- What we are looking for here is the situation -- where the Esize given would be exactly right -- if there was a pragma Pack (resulting in the -- component size being the same as the RM_Size). -- Furthermore, the component type size must be -- an odd size (not a multiple of storage unit) begin if Esize (E) = Len * Rsiz and then Rsiz mod System_Storage_Unit /= 0 then Error_Msg_NE ("size given for& too small", Size_Clause (E), E); Error_Msg_N ("\explicit pragma Pack is required", Size_Clause (E)); end if; end; end if; end if; end; -- If any of the index types was an enumeration type with -- a non-standard rep clause, then we indicate that the -- array type is always packed (even if it is not bit packed). if Non_Standard_Enum then Set_Has_Non_Standard_Rep (Base_Type (E)); Set_Is_Packed (Base_Type (E)); end if; Set_Component_Alignment_If_Not_Set (E); -- If the array is packed, we must create the packed array -- type to be used to actually implement the type. This is -- only needed for real array types (not for string literal -- types, since they are present only for the front end). if Is_Packed (E) and then Ekind (E) /= E_String_Literal_Subtype then Create_Packed_Array_Type (E); Freeze_And_Append (Packed_Array_Type (E), Loc, Result); -- Size information of packed array type is copied to the -- array type, since this is really the representation. Set_Size_Info (E, Packed_Array_Type (E)); Set_RM_Size (E, RM_Size (Packed_Array_Type (E))); end if; -- For non-packed arrays set the alignment of the array -- to the alignment of the component type if it is unknown. -- Skip this in the atomic case, since atomic arrays may -- need larger alignments. if not Is_Packed (E) and then Unknown_Alignment (E) and then Known_Alignment (Ctyp) and then Known_Static_Component_Size (E) and then Known_Static_Esize (Ctyp) and then Esize (Ctyp) = Component_Size (E) and then not Is_Atomic (E) then Set_Alignment (E, Alignment (Component_Type (E))); end if; end; -- For a class-wide type, the corresponding specific type is -- frozen as well (RM 13.14(15)) elsif Is_Class_Wide_Type (E) then Freeze_And_Append (Root_Type (E), Loc, Result); -- If the Class_Wide_Type is an Itype (when type is the anonymous -- parent of a derived type) and it is a library-level entity, -- generate an itype reference for it. Otherwise, its first -- explicit reference may be in an inner scope, which will be -- rejected by the back-end. if Is_Itype (E) and then Is_Compilation_Unit (Scope (E)) then declare Ref : constant Node_Id := Make_Itype_Reference (Loc); begin Set_Itype (Ref, E); if No (Result) then Result := New_List (Ref); else Append (Ref, Result); end if; end; end if; -- The equivalent type associated with a class-wide subtype -- needs to be frozen to ensure that its layout is done. -- Class-wide subtypes are currently only frozen on targets -- requiring front-end layout (see New_Class_Wide_Subtype -- and Make_CW_Equivalent_Type in exp_util.adb). if Ekind (E) = E_Class_Wide_Subtype and then Present (Equivalent_Type (E)) then Freeze_And_Append (Equivalent_Type (E), Loc, Result); end if; -- For a record (sub)type, freeze all the component types (RM -- 13.14(15). We test for E_Record_(sub)Type here, rather than -- using Is_Record_Type, because we don't want to attempt the -- freeze for the case of a private type with record extension -- (we will do that later when the full type is frozen). elsif Ekind (E) = E_Record_Type or else Ekind (E) = E_Record_Subtype then Freeze_Record_Type (E); -- For a concurrent type, freeze corresponding record type. This -- does not correpond to any specific rule in the RM, but the -- record type is essentially part of the concurrent type. -- Freeze as well all local entities. This includes record types -- created for entry parameter blocks, and whatever local entities -- may appear in the private part. elsif Is_Concurrent_Type (E) then if Present (Corresponding_Record_Type (E)) then Freeze_And_Append (Corresponding_Record_Type (E), Loc, Result); end if; Comp := First_Entity (E); while Present (Comp) loop if Is_Type (Comp) then Freeze_And_Append (Comp, Loc, Result); elsif (Ekind (Comp)) /= E_Function then if Is_Itype (Etype (Comp)) and then Underlying_Type (Scope (Etype (Comp))) = E then Undelay_Type (Etype (Comp)); end if; Freeze_And_Append (Etype (Comp), Loc, Result); end if; Next_Entity (Comp); end loop; -- Private types are required to point to the same freeze node as -- their corresponding full views. The freeze node itself has to -- point to the partial view of the entity (because from the partial -- view, we can retrieve the full view, but not the reverse). -- However, in order to freeze correctly, we need to freeze the full -- view. If we are freezing at the end of a scope (or within the -- scope of the private type), the partial and full views will have -- been swapped, the full view appears first in the entity chain and -- the swapping mechanism ensures that the pointers are properly set -- (on scope exit). -- If we encounter the partial view before the full view (e.g. when -- freezing from another scope), we freeze the full view, and then -- set the pointers appropriately since we cannot rely on swapping to -- fix things up (subtypes in an outer scope might not get swapped). elsif Is_Incomplete_Or_Private_Type (E) and then not Is_Generic_Type (E) then -- Case of full view present if Present (Full_View (E)) then -- If full view has already been frozen, then no further -- processing is required if Is_Frozen (Full_View (E)) then Set_Has_Delayed_Freeze (E, False); Set_Freeze_Node (E, Empty); Check_Debug_Info_Needed (E); -- Otherwise freeze full view and patch the pointers so that -- the freeze node will elaborate both views in the back-end. else declare Full : constant Entity_Id := Full_View (E); begin if Is_Private_Type (Full) and then Present (Underlying_Full_View (Full)) then Freeze_And_Append (Underlying_Full_View (Full), Loc, Result); end if; Freeze_And_Append (Full, Loc, Result); if Has_Delayed_Freeze (E) then F_Node := Freeze_Node (Full); if Present (F_Node) then Set_Freeze_Node (E, F_Node); Set_Entity (F_Node, E); else -- {Incomplete,Private}_Subtypes -- with Full_Views constrained by discriminants Set_Has_Delayed_Freeze (E, False); Set_Freeze_Node (E, Empty); end if; end if; end; Check_Debug_Info_Needed (E); end if; -- AI-117 requires that the convention of a partial view be the -- same as the convention of the full view. Note that this is a -- recognized breach of privacy, but it's essential for logical -- consistency of representation, and the lack of a rule in -- RM95 was an oversight. Set_Convention (E, Convention (Full_View (E))); Set_Size_Known_At_Compile_Time (E, Size_Known_At_Compile_Time (Full_View (E))); -- Size information is copied from the full view to the -- incomplete or private view for consistency -- We skip this is the full view is not a type. This is very -- strange of course, and can only happen as a result of -- certain illegalities, such as a premature attempt to derive -- from an incomplete type. if Is_Type (Full_View (E)) then Set_Size_Info (E, Full_View (E)); Set_RM_Size (E, RM_Size (Full_View (E))); end if; return Result; -- Case of no full view present. If entity is derived or subtype, -- it is safe to freeze, correctness depends on the frozen status -- of parent. Otherwise it is either premature usage, or a Taft -- amendment type, so diagnosis is at the point of use and the -- type might be frozen later. elsif E /= Base_Type (E) or else Is_Derived_Type (E) then null; else Set_Is_Frozen (E, False); return No_List; end if; -- For access subprogram, freeze types of all formals, the return -- type was already frozen, since it is the Etype of the function. elsif Ekind (E) = E_Subprogram_Type then Formal := First_Formal (E); while Present (Formal) loop Freeze_And_Append (Etype (Formal), Loc, Result); Next_Formal (Formal); end loop; -- If the return type requires a transient scope, and we are on -- a target allowing functions to return with a depressed stack -- pointer, then we mark the function as requiring this treatment. if Functions_Return_By_DSP_On_Target and then Requires_Transient_Scope (Etype (E)) then Set_Function_Returns_With_DSP (E); end if; Freeze_Subprogram (E); -- AI-326: Check wrong use of tag incomplete type -- -- type T is tagged; -- type Acc is access function (X : T) return T; -- ERROR if Ekind (Etype (E)) = E_Incomplete_Type and then Is_Tagged_Type (Etype (E)) and then No (Full_View (Etype (E))) then Error_Msg_N ("(Ada 2005): invalid use of tagged incomplete type", E); end if; -- For access to a protected subprogram, freeze the equivalent type -- (however this is not set if we are not generating code or if this -- is an anonymous type used just for resolution). elsif Ekind (E) = E_Access_Protected_Subprogram_Type then -- AI-326: Check wrong use of tagged incomplete types -- type T is tagged; -- type As3D is access protected -- function (X : Float) return T; -- ERROR declare Etyp : Entity_Id; begin Etyp := Etype (Directly_Designated_Type (E)); if Is_Class_Wide_Type (Etyp) then Etyp := Etype (Etyp); end if; if Ekind (Etyp) = E_Incomplete_Type and then Is_Tagged_Type (Etyp) and then No (Full_View (Etyp)) then Error_Msg_N ("(Ada 2005): invalid use of tagged incomplete type", E); end if; end; if Present (Equivalent_Type (E)) then Freeze_And_Append (Equivalent_Type (E), Loc, Result); end if; end if; -- Generic types are never seen by the back-end, and are also not -- processed by the expander (since the expander is turned off for -- generic processing), so we never need freeze nodes for them. if Is_Generic_Type (E) then return Result; end if; -- Some special processing for non-generic types to complete -- representation details not known till the freeze point. if Is_Fixed_Point_Type (E) then Freeze_Fixed_Point_Type (E); -- Some error checks required for ordinary fixed-point type. Defer -- these till the freeze-point since we need the small and range -- values. We only do these checks for base types if Is_Ordinary_Fixed_Point_Type (E) and then E = Base_Type (E) then if Small_Value (E) < Ureal_2_M_80 then Error_Msg_Name_1 := Name_Small; Error_Msg_N ("`&''%` is too small, minimum is 2.0'*'*(-80)", E); elsif Small_Value (E) > Ureal_2_80 then Error_Msg_Name_1 := Name_Small; Error_Msg_N ("`&''%` is too large, maximum is 2.0'*'*80", E); end if; if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then Error_Msg_Name_1 := Name_First; Error_Msg_N ("`&''%` is too small, minimum is -10.0'*'*36", E); end if; if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then Error_Msg_Name_1 := Name_Last; Error_Msg_N ("`&''%` is too large, maximum is 10.0'*'*36", E); end if; end if; elsif Is_Enumeration_Type (E) then Freeze_Enumeration_Type (E); elsif Is_Integer_Type (E) then Adjust_Esize_For_Alignment (E); elsif Is_Access_Type (E) then -- Check restriction for standard storage pool if No (Associated_Storage_Pool (E)) then Check_Restriction (No_Standard_Storage_Pools, E); end if; -- Deal with error message for pure access type. This is not an -- error in Ada 2005 if there is no pool (see AI-366). if Is_Pure_Unit_Access_Type (E) and then (Ada_Version < Ada_05 or else not No_Pool_Assigned (E)) then Error_Msg_N ("named access type not allowed in pure unit", E); end if; end if; -- Case of composite types if Is_Composite_Type (E) then -- AI-117 requires that all new primitives of a tagged type must -- inherit the convention of the full view of the type. Inherited -- and overriding operations are defined to inherit the convention -- of their parent or overridden subprogram (also specified in -- AI-117), which will have occurred earlier (in Derive_Subprogram -- and New_Overloaded_Entity). Here we set the convention of -- primitives that are still convention Ada, which will ensure -- that any new primitives inherit the type's convention. -- Class-wide types can have a foreign convention inherited from -- their specific type, but are excluded from this since they -- don't have any associated primitives. if Is_Tagged_Type (E) and then not Is_Class_Wide_Type (E) and then Convention (E) /= Convention_Ada then declare Prim_List : constant Elist_Id := Primitive_Operations (E); Prim : Elmt_Id; begin Prim := First_Elmt (Prim_List); while Present (Prim) loop if Convention (Node (Prim)) = Convention_Ada then Set_Convention (Node (Prim), Convention (E)); end if; Next_Elmt (Prim); end loop; end; end if; end if; -- Generate primitive operation references for a tagged type if Is_Tagged_Type (E) and then not Is_Class_Wide_Type (E) then declare Prim_List : Elist_Id; Prim : Elmt_Id; Ent : Entity_Id; Aux_E : Entity_Id; begin -- Handle subtypes if Ekind (E) = E_Protected_Subtype or else Ekind (E) = E_Task_Subtype then Aux_E := Etype (E); else Aux_E := E; end if; -- Ada 2005 (AI-345): In case of concurrent type generate -- reference to the wrapper that allow us to dispatch calls -- through their implemented abstract interface types. -- The check for Present here is to protect against previously -- reported critical errors. if Is_Concurrent_Type (Aux_E) and then Present (Corresponding_Record_Type (Aux_E)) then pragma Assert (not Is_Empty_Elmt_List (Abstract_Interfaces (Corresponding_Record_Type (Aux_E)))); Prim_List := Primitive_Operations (Corresponding_Record_Type (Aux_E)); else Prim_List := Primitive_Operations (Aux_E); end if; -- Loop to generate references for primitive operations if Present (Prim_List) then Prim := First_Elmt (Prim_List); while Present (Prim) loop -- If the operation is derived, get the original for -- cross-reference purposes (it is the original for -- which we want the xref, and for which the comes -- from source test needs to be performed). Ent := Node (Prim); while Present (Alias (Ent)) loop Ent := Alias (Ent); end loop; Generate_Reference (E, Ent, 'p', Set_Ref => False); Next_Elmt (Prim); end loop; end if; end; end if; -- Now that all types from which E may depend are frozen, see if the -- size is known at compile time, if it must be unsigned, or if -- strict alignent is required Check_Compile_Time_Size (E); Check_Unsigned_Type (E); if Base_Type (E) = E then Check_Strict_Alignment (E); end if; -- Do not allow a size clause for a type which does not have a size -- that is known at compile time if Has_Size_Clause (E) and then not Size_Known_At_Compile_Time (E) then -- Supress this message if errors posted on E, even if we are -- in all errors mode, since this is often a junk message if not Error_Posted (E) then Error_Msg_N ("size clause not allowed for variable length type", Size_Clause (E)); end if; end if; -- Remaining process is to set/verify the representation information, -- in particular the size and alignment values. This processing is -- not required for generic types, since generic types do not play -- any part in code generation, and so the size and alignment values -- for such types are irrelevant. if Is_Generic_Type (E) then return Result; -- Otherwise we call the layout procedure else Layout_Type (E); end if; -- End of freeze processing for type entities end if; -- Here is where we logically freeze the current entity. If it has a -- freeze node, then this is the point at which the freeze node is -- linked into the result list. if Has_Delayed_Freeze (E) then -- If a freeze node is already allocated, use it, otherwise allocate -- a new one. The preallocation happens in the case of anonymous base -- types, where we preallocate so that we can set First_Subtype_Link. -- Note that we reset the Sloc to the current freeze location. if Present (Freeze_Node (E)) then F_Node := Freeze_Node (E); Set_Sloc (F_Node, Loc); else F_Node := New_Node (N_Freeze_Entity, Loc); Set_Freeze_Node (E, F_Node); Set_Access_Types_To_Process (F_Node, No_Elist); Set_TSS_Elist (F_Node, No_Elist); Set_Actions (F_Node, No_List); end if; Set_Entity (F_Node, E); if Result = No_List then Result := New_List (F_Node); else Append (F_Node, Result); end if; -- A final pass over record types with discriminants. If the type -- has an incomplete declaration, there may be constrained access -- subtypes declared elsewhere, which do not depend on the discrimi- -- nants of the type, and which are used as component types (i.e. -- the full view is a recursive type). The designated types of these -- subtypes can only be elaborated after the type itself, and they -- need an itype reference. if Ekind (E) = E_Record_Type and then Has_Discriminants (E) then declare Comp : Entity_Id; IR : Node_Id; Typ : Entity_Id; begin Comp := First_Component (E); while Present (Comp) loop Typ := Etype (Comp); if Ekind (Comp) = E_Component and then Is_Access_Type (Typ) and then Scope (Typ) /= E and then Base_Type (Designated_Type (Typ)) = E and then Is_Itype (Designated_Type (Typ)) then IR := Make_Itype_Reference (Sloc (Comp)); Set_Itype (IR, Designated_Type (Typ)); Append (IR, Result); end if; Next_Component (Comp); end loop; end; end if; end if; -- When a type is frozen, the first subtype of the type is frozen as -- well (RM 13.14(15)). This has to be done after freezing the type, -- since obviously the first subtype depends on its own base type. if Is_Type (E) then Freeze_And_Append (First_Subtype (E), Loc, Result); -- If we just froze a tagged non-class wide record, then freeze the -- corresponding class-wide type. This must be done after the tagged -- type itself is frozen, because the class-wide type refers to the -- tagged type which generates the class. if Is_Tagged_Type (E) and then not Is_Class_Wide_Type (E) and then Present (Class_Wide_Type (E)) then Freeze_And_Append (Class_Wide_Type (E), Loc, Result); end if; end if; Check_Debug_Info_Needed (E); -- Special handling for subprograms if Is_Subprogram (E) then -- If subprogram has address clause then reset Is_Public flag, since -- we do not want the backend to generate external references. if Present (Address_Clause (E)) and then not Is_Library_Level_Entity (E) then Set_Is_Public (E, False); -- If no address clause and not intrinsic, then for imported -- subprogram in main unit, generate descriptor if we are in -- Propagate_Exceptions mode. elsif Propagate_Exceptions and then Is_Imported (E) and then not Is_Intrinsic_Subprogram (E) and then Convention (E) /= Convention_Stubbed then if Result = No_List then Result := Empty_List; end if; end if; end if; return Result; end Freeze_Entity; ----------------------------- -- Freeze_Enumeration_Type -- ----------------------------- procedure Freeze_Enumeration_Type (Typ : Entity_Id) is begin if Has_Foreign_Convention (Typ) and then not Has_Size_Clause (Typ) and then Esize (Typ) < Standard_Integer_Size then Init_Esize (Typ, Standard_Integer_Size); else Adjust_Esize_For_Alignment (Typ); end if; end Freeze_Enumeration_Type; ----------------------- -- Freeze_Expression -- ----------------------- procedure Freeze_Expression (N : Node_Id) is In_Def_Exp : constant Boolean := In_Default_Expression; Typ : Entity_Id; Nam : Entity_Id; Desig_Typ : Entity_Id; P : Node_Id; Parent_P : Node_Id; Freeze_Outside : Boolean := False; -- This flag is set true if the entity must be frozen outside the -- current subprogram. This happens in the case of expander generated -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do -- not freeze all entities like other bodies, but which nevertheless -- may reference entities that have to be frozen before the body and -- obviously cannot be frozen inside the body. function In_Exp_Body (N : Node_Id) return Boolean; -- Given an N_Handled_Sequence_Of_Statements node N, determines whether -- it is the handled statement sequence of an expander-generated -- subprogram (init proc, or stream subprogram). If so, it returns -- True, otherwise False. ----------------- -- In_Exp_Body -- ----------------- function In_Exp_Body (N : Node_Id) return Boolean is P : Node_Id; begin if Nkind (N) = N_Subprogram_Body then P := N; else P := Parent (N); end if; if Nkind (P) /= N_Subprogram_Body then return False; else P := Defining_Unit_Name (Specification (P)); if Nkind (P) = N_Defining_Identifier and then (Is_Init_Proc (P) or else Is_TSS (P, TSS_Stream_Input) or else Is_TSS (P, TSS_Stream_Output) or else Is_TSS (P, TSS_Stream_Read) or else Is_TSS (P, TSS_Stream_Write)) then return True; else return False; end if; end if; end In_Exp_Body; -- Start of processing for Freeze_Expression begin -- Immediate return if freezing is inhibited. This flag is set by the -- analyzer to stop freezing on generated expressions that would cause -- freezing if they were in the source program, but which are not -- supposed to freeze, since they are created. if Must_Not_Freeze (N) then return; end if; -- If expression is non-static, then it does not freeze in a default -- expression, see section "Handling of Default Expressions" in the -- spec of package Sem for further details. Note that we have to -- make sure that we actually have a real expression (if we have -- a subtype indication, we can't test Is_Static_Expression!) if In_Def_Exp and then Nkind (N) in N_Subexpr and then not Is_Static_Expression (N) then return; end if; -- Freeze type of expression if not frozen already Typ := Empty; if Nkind (N) in N_Has_Etype then if not Is_Frozen (Etype (N)) then Typ := Etype (N); -- Base type may be an derived numeric type that is frozen at -- the point of declaration, but first_subtype is still unfrozen. elsif not Is_Frozen (First_Subtype (Etype (N))) then Typ := First_Subtype (Etype (N)); end if; end if; -- For entity name, freeze entity if not frozen already. A special -- exception occurs for an identifier that did not come from source. -- We don't let such identifiers freeze a non-internal entity, i.e. -- an entity that did come from source, since such an identifier was -- generated by the expander, and cannot have any semantic effect on -- the freezing semantics. For example, this stops the parameter of -- an initialization procedure from freezing the variable. if Is_Entity_Name (N) and then not Is_Frozen (Entity (N)) and then (Nkind (N) /= N_Identifier or else Comes_From_Source (N) or else not Comes_From_Source (Entity (N))) then Nam := Entity (N); else Nam := Empty; end if; -- For an allocator freeze designated type if not frozen already -- For an aggregate whose component type is an access type, freeze the -- designated type now, so that its freeze does not appear within the -- loop that might be created in the expansion of the aggregate. If the -- designated type is a private type without full view, the expression -- cannot contain an allocator, so the type is not frozen. Desig_Typ := Empty; case Nkind (N) is when N_Allocator => Desig_Typ := Designated_Type (Etype (N)); when N_Aggregate => if Is_Array_Type (Etype (N)) and then Is_Access_Type (Component_Type (Etype (N))) then Desig_Typ := Designated_Type (Component_Type (Etype (N))); end if; when N_Selected_Component | N_Indexed_Component | N_Slice => if Is_Access_Type (Etype (Prefix (N))) then Desig_Typ := Designated_Type (Etype (Prefix (N))); end if; when others => null; end case; if Desig_Typ /= Empty and then (Is_Frozen (Desig_Typ) or else (not Is_Fully_Defined (Desig_Typ))) then Desig_Typ := Empty; end if; -- All done if nothing needs freezing if No (Typ) and then No (Nam) and then No (Desig_Typ) then return; end if; -- Loop for looking at the right place to insert the freeze nodes -- exiting from the loop when it is appropriate to insert the freeze -- node before the current node P. -- Also checks some special exceptions to the freezing rules. These -- cases result in a direct return, bypassing the freeze action. P := N; loop Parent_P := Parent (P); -- If we don't have a parent, then we are not in a well-formed tree. -- This is an unusual case, but there are some legitimate situations -- in which this occurs, notably when the expressions in the range of -- a type declaration are resolved. We simply ignore the freeze -- request in this case. Is this right ??? if No (Parent_P) then return; end if; -- See if we have got to an appropriate point in the tree case Nkind (Parent_P) is -- A special test for the exception of (RM 13.14(8)) for the case -- of per-object expressions (RM 3.8(18)) occurring in component -- definition or a discrete subtype definition. Note that we test -- for a component declaration which includes both cases we are -- interested in, and furthermore the tree does not have explicit -- nodes for either of these two constructs. when N_Component_Declaration => -- The case we want to test for here is an identifier that is -- a per-object expression, this is either a discriminant that -- appears in a context other than the component declaration -- or it is a reference to the type of the enclosing construct. -- For either of these cases, we skip the freezing if not In_Default_Expression and then Nkind (N) = N_Identifier and then (Present (Entity (N))) then -- We recognize the discriminant case by just looking for -- a reference to a discriminant. It can only be one for -- the enclosing construct. Skip freezing in this case. if Ekind (Entity (N)) = E_Discriminant then return; -- For the case of a reference to the enclosing record, -- (or task or protected type), we look for a type that -- matches the current scope. elsif Entity (N) = Current_Scope then return; end if; end if; -- If we have an enumeration literal that appears as the choice in -- the aggregate of an enumeration representation clause, then -- freezing does not occur (RM 13.14(10)). when N_Enumeration_Representation_Clause => -- The case we are looking for is an enumeration literal if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal) and then Is_Enumeration_Type (Etype (N)) then -- If enumeration literal appears directly as the choice, -- do not freeze (this is the normal non-overloade case) if Nkind (Parent (N)) = N_Component_Association and then First (Choices (Parent (N))) = N then return; -- If enumeration literal appears as the name of function -- which is the choice, then also do not freeze. This -- happens in the overloaded literal case, where the -- enumeration literal is temporarily changed to a function -- call for overloading analysis purposes. elsif Nkind (Parent (N)) = N_Function_Call and then Nkind (Parent (Parent (N))) = N_Component_Association and then First (Choices (Parent (Parent (N)))) = Parent (N) then return; end if; end if; -- Normally if the parent is a handled sequence of statements, -- then the current node must be a statement, and that is an -- appropriate place to insert a freeze node. when N_Handled_Sequence_Of_Statements => -- An exception occurs when the sequence of statements is for -- an expander generated body that did not do the usual freeze -- all operation. In this case we usually want to freeze -- outside this body, not inside it, and we skip past the -- subprogram body that we are inside. if In_Exp_Body (Parent_P) then -- However, we *do* want to freeze at this point if we have -- an entity to freeze, and that entity is declared *inside* -- the body of the expander generated procedure. This case -- is recognized by the scope of the type, which is either -- the spec for some enclosing body, or (in the case of -- init_procs, for which there are no separate specs) the -- current scope. declare Subp : constant Node_Id := Parent (Parent_P); Cspc : Entity_Id; begin if Nkind (Subp) = N_Subprogram_Body then Cspc := Corresponding_Spec (Subp); if (Present (Typ) and then Scope (Typ) = Cspc) or else (Present (Nam) and then Scope (Nam) = Cspc) then exit; elsif Present (Typ) and then Scope (Typ) = Current_Scope and then Current_Scope = Defining_Entity (Subp) then exit; end if; end if; end; -- If not that exception to the exception, then this is -- where we delay the freeze till outside the body. Parent_P := Parent (Parent_P); Freeze_Outside := True; -- Here if normal case where we are in handled statement -- sequence and want to do the insertion right there. else exit; end if; -- If parent is a body or a spec or a block, then the current node -- is a statement or declaration and we can insert the freeze node -- before it. when N_Package_Specification | N_Package_Body | N_Subprogram_Body | N_Task_Body | N_Protected_Body | N_Entry_Body | N_Block_Statement => exit; -- The expander is allowed to define types in any statements list, -- so any of the following parent nodes also mark a freezing point -- if the actual node is in a list of statements or declarations. when N_Exception_Handler | N_If_Statement | N_Elsif_Part | N_Case_Statement_Alternative | N_Compilation_Unit_Aux | N_Selective_Accept | N_Accept_Alternative | N_Delay_Alternative | N_Conditional_Entry_Call | N_Entry_Call_Alternative | N_Triggering_Alternative | N_Abortable_Part | N_Freeze_Entity => exit when Is_List_Member (P); -- Note: The N_Loop_Statement is a special case. A type that -- appears in the source can never be frozen in a loop (this -- occurs only because of a loop expanded by the expander), so we -- keep on going. Otherwise we terminate the search. Same is true -- of any entity which comes from source. (if they have predefined -- type, that type does not appear to come from source, but the -- entity should not be frozen here). when N_Loop_Statement => exit when not Comes_From_Source (Etype (N)) and then (No (Nam) or else not Comes_From_Source (Nam)); -- For all other cases, keep looking at parents when others => null; end case; -- We fall through the case if we did not yet find the proper -- place in the free for inserting the freeze node, so climb! P := Parent_P; end loop; -- If the expression appears in a record or an initialization procedure, -- the freeze nodes are collected and attached to the current scope, to -- be inserted and analyzed on exit from the scope, to insure that -- generated entities appear in the correct scope. If the expression is -- a default for a discriminant specification, the scope is still void. -- The expression can also appear in the discriminant part of a private -- or concurrent type. -- If the expression appears in a constrained subcomponent of an -- enclosing record declaration, the freeze nodes must be attached to -- the outer record type so they can eventually be placed in the -- enclosing declaration list. -- The other case requiring this special handling is if we are in a -- default expression, since in that case we are about to freeze a -- static type, and the freeze scope needs to be the outer scope, not -- the scope of the subprogram with the default parameter. -- For default expressions in generic units, the Move_Freeze_Nodes -- mechanism (see sem_ch12.adb) takes care of placing them at the proper -- place, after the generic unit. if (In_Def_Exp and not Inside_A_Generic) or else Freeze_Outside or else (Is_Type (Current_Scope) and then (not Is_Concurrent_Type (Current_Scope) or else not Has_Completion (Current_Scope))) or else Ekind (Current_Scope) = E_Void then declare Loc : constant Source_Ptr := Sloc (Current_Scope); Freeze_Nodes : List_Id := No_List; Pos : Int := Scope_Stack.Last; begin if Present (Desig_Typ) then Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes); end if; if Present (Typ) then Freeze_And_Append (Typ, Loc, Freeze_Nodes); end if; if Present (Nam) then Freeze_And_Append (Nam, Loc, Freeze_Nodes); end if; -- The current scope may be that of a constrained component of -- an enclosing record declaration, which is above the current -- scope in the scope stack. if Is_Record_Type (Scope (Current_Scope)) then Pos := Pos - 1; end if; if Is_Non_Empty_List (Freeze_Nodes) then if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then Scope_Stack.Table (Pos).Pending_Freeze_Actions := Freeze_Nodes; else Append_List (Freeze_Nodes, Scope_Stack.Table (Pos).Pending_Freeze_Actions); end if; end if; end; return; end if; -- Now we have the right place to do the freezing. First, a special -- adjustment, if we are in default expression analysis mode, these -- freeze actions must not be thrown away (normally all inserted actions -- are thrown away in this mode. However, the freeze actions are from -- static expressions and one of the important reasons we are doing this -- special analysis is to get these freeze actions. Therefore we turn -- off the In_Default_Expression mode to propagate these freeze actions. -- This also means they get properly analyzed and expanded. In_Default_Expression := False; -- Freeze the designated type of an allocator (RM 13.14(13)) if Present (Desig_Typ) then Freeze_Before (P, Desig_Typ); end if; -- Freeze type of expression (RM 13.14(10)). Note that we took care of -- the enumeration representation clause exception in the loop above. if Present (Typ) then Freeze_Before (P, Typ); end if; -- Freeze name if one is present (RM 13.14(11)) if Present (Nam) then Freeze_Before (P, Nam); end if; In_Default_Expression := In_Def_Exp; end Freeze_Expression; ----------------------------- -- Freeze_Fixed_Point_Type -- ----------------------------- -- Certain fixed-point types and subtypes, including implicit base types -- and declared first subtypes, have not yet set up a range. This is -- because the range cannot be set until the Small and Size values are -- known, and these are not known till the type is frozen. -- To signal this case, Scalar_Range contains an unanalyzed syntactic range -- whose bounds are unanalyzed real literals. This routine will recognize -- this case, and transform this range node into a properly typed range -- with properly analyzed and resolved values. procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is Rng : constant Node_Id := Scalar_Range (Typ); Lo : constant Node_Id := Low_Bound (Rng); Hi : constant Node_Id := High_Bound (Rng); Btyp : constant Entity_Id := Base_Type (Typ); Brng : constant Node_Id := Scalar_Range (Btyp); BLo : constant Node_Id := Low_Bound (Brng); BHi : constant Node_Id := High_Bound (Brng); Small : constant Ureal := Small_Value (Typ); Loval : Ureal; Hival : Ureal; Atype : Entity_Id; Actual_Size : Nat; function Fsize (Lov, Hiv : Ureal) return Nat; -- Returns size of type with given bounds. Also leaves these -- bounds set as the current bounds of the Typ. ----------- -- Fsize -- ----------- function Fsize (Lov, Hiv : Ureal) return Nat is begin Set_Realval (Lo, Lov); Set_Realval (Hi, Hiv); return Minimum_Size (Typ); end Fsize; -- Start of processing for Freeze_Fixed_Point_Type begin -- If Esize of a subtype has not previously been set, set it now if Unknown_Esize (Typ) then Atype := Ancestor_Subtype (Typ); if Present (Atype) then Set_Esize (Typ, Esize (Atype)); else Set_Esize (Typ, Esize (Base_Type (Typ))); end if; end if; -- Immediate return if the range is already analyzed. This means that -- the range is already set, and does not need to be computed by this -- routine. if Analyzed (Rng) then return; end if; -- Immediate return if either of the bounds raises Constraint_Error if Raises_Constraint_Error (Lo) or else Raises_Constraint_Error (Hi) then return; end if; Loval := Realval (Lo); Hival := Realval (Hi); -- Ordinary fixed-point case if Is_Ordinary_Fixed_Point_Type (Typ) then -- For the ordinary fixed-point case, we are allowed to fudge the -- end-points up or down by small. Generally we prefer to fudge up, -- i.e. widen the bounds for non-model numbers so that the end points -- are included. However there are cases in which this cannot be -- done, and indeed cases in which we may need to narrow the bounds. -- The following circuit makes the decision. -- Note: our terminology here is that Incl_EP means that the bounds -- are widened by Small if necessary to include the end points, and -- Excl_EP means that the bounds are narrowed by Small to exclude the -- end-points if this reduces the size. -- Note that in the Incl case, all we care about is including the -- end-points. In the Excl case, we want to narrow the bounds as -- much as permitted by the RM, to give the smallest possible size. Fudge : declare Loval_Incl_EP : Ureal; Hival_Incl_EP : Ureal; Loval_Excl_EP : Ureal; Hival_Excl_EP : Ureal; Size_Incl_EP : Nat; Size_Excl_EP : Nat; Model_Num : Ureal; First_Subt : Entity_Id; Actual_Lo : Ureal; Actual_Hi : Ureal; begin -- First step. Base types are required to be symmetrical. Right -- now, the base type range is a copy of the first subtype range. -- This will be corrected before we are done, but right away we -- need to deal with the case where both bounds are non-negative. -- In this case, we set the low bound to the negative of the high -- bound, to make sure that the size is computed to include the -- required sign. Note that we do not need to worry about the -- case of both bounds negative, because the sign will be dealt -- with anyway. Furthermore we can't just go making such a bound -- symmetrical, since in a twos-complement system, there is an -- extra negative value which could not be accomodated on the -- positive side. if Typ = Btyp and then not UR_Is_Negative (Loval) and then Hival > Loval then Loval := -Hival; Set_Realval (Lo, Loval); end if; -- Compute the fudged bounds. If the number is a model number, -- then we do nothing to include it, but we are allowed to backoff -- to the next adjacent model number when we exclude it. If it is -- not a model number then we straddle the two values with the -- model numbers on either side. Model_Num := UR_Trunc (Loval / Small) * Small; if Loval = Model_Num then Loval_Incl_EP := Model_Num; else Loval_Incl_EP := Model_Num - Small; end if; -- The low value excluding the end point is Small greater, but -- we do not do this exclusion if the low value is positive, -- since it can't help the size and could actually hurt by -- crossing the high bound. if UR_Is_Negative (Loval_Incl_EP) then Loval_Excl_EP := Loval_Incl_EP + Small; else Loval_Excl_EP := Loval_Incl_EP; end if; -- Similar processing for upper bound and high value Model_Num := UR_Trunc (Hival / Small) * Small; if Hival = Model_Num then Hival_Incl_EP := Model_Num; else Hival_Incl_EP := Model_Num + Small; end if; if UR_Is_Positive (Hival_Incl_EP) then Hival_Excl_EP := Hival_Incl_EP - Small; else Hival_Excl_EP := Hival_Incl_EP; end if; -- One further adjustment is needed. In the case of subtypes, we -- cannot go outside the range of the base type, or we get -- peculiarities, and the base type range is already set. This -- only applies to the Incl values, since clearly the Excl values -- are already as restricted as they are allowed to be. if Typ /= Btyp then Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo)); Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi)); end if; -- Get size including and excluding end points Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP); Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP); -- No need to exclude end-points if it does not reduce size if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then Loval_Excl_EP := Loval_Incl_EP; end if; if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then Hival_Excl_EP := Hival_Incl_EP; end if; -- Now we set the actual size to be used. We want to use the -- bounds fudged up to include the end-points but only if this -- can be done without violating a specifically given size -- size clause or causing an unacceptable increase in size. -- Case of size clause given if Has_Size_Clause (Typ) then -- Use the inclusive size only if it is consistent with -- the explicitly specified size. if Size_Incl_EP <= RM_Size (Typ) then Actual_Lo := Loval_Incl_EP; Actual_Hi := Hival_Incl_EP; Actual_Size := Size_Incl_EP; -- If the inclusive size is too large, we try excluding -- the end-points (will be caught later if does not work). else Actual_Lo := Loval_Excl_EP; Actual_Hi := Hival_Excl_EP; Actual_Size := Size_Excl_EP; end if; -- Case of size clause not given else -- If we have a base type whose corresponding first subtype -- has an explicit size that is large enough to include our -- end-points, then do so. There is no point in working hard -- to get a base type whose size is smaller than the specified -- size of the first subtype. First_Subt := First_Subtype (Typ); if Has_Size_Clause (First_Subt) and then Size_Incl_EP <= Esize (First_Subt) then Actual_Size := Size_Incl_EP; Actual_Lo := Loval_Incl_EP; Actual_Hi := Hival_Incl_EP; -- If excluding the end-points makes the size smaller and -- results in a size of 8,16,32,64, then we take the smaller -- size. For the 64 case, this is compulsory. For the other -- cases, it seems reasonable. We like to include end points -- if we can, but not at the expense of moving to the next -- natural boundary of size. elsif Size_Incl_EP /= Size_Excl_EP and then (Size_Excl_EP = 8 or else Size_Excl_EP = 16 or else Size_Excl_EP = 32 or else Size_Excl_EP = 64) then Actual_Size := Size_Excl_EP; Actual_Lo := Loval_Excl_EP; Actual_Hi := Hival_Excl_EP; -- Otherwise we can definitely include the end points else Actual_Size := Size_Incl_EP; Actual_Lo := Loval_Incl_EP; Actual_Hi := Hival_Incl_EP; end if; -- One pathological case: normally we never fudge a low bound -- down, since it would seem to increase the size (if it has -- any effect), but for ranges containing single value, or no -- values, the high bound can be small too large. Consider: -- type t is delta 2.0**(-14) -- range 131072.0 .. 0; -- That lower bound is *just* outside the range of 32 bits, and -- does need fudging down in this case. Note that the bounds -- will always have crossed here, since the high bound will be -- fudged down if necessary, as in the case of: -- type t is delta 2.0**(-14) -- range 131072.0 .. 131072.0; -- So we detect the situation by looking for crossed bounds, -- and if the bounds are crossed, and the low bound is greater -- than zero, we will always back it off by small, since this -- is completely harmless. if Actual_Lo > Actual_Hi then if UR_Is_Positive (Actual_Lo) then Actual_Lo := Loval_Incl_EP - Small; Actual_Size := Fsize (Actual_Lo, Actual_Hi); -- And of course, we need to do exactly the same parallel -- fudge for flat ranges in the negative region. elsif UR_Is_Negative (Actual_Hi) then Actual_Hi := Hival_Incl_EP + Small; Actual_Size := Fsize (Actual_Lo, Actual_Hi); end if; end if; end if; Set_Realval (Lo, Actual_Lo); Set_Realval (Hi, Actual_Hi); end Fudge; -- For the decimal case, none of this fudging is required, since there -- are no end-point problems in the decimal case (the end-points are -- always included). else Actual_Size := Fsize (Loval, Hival); end if; -- At this stage, the actual size has been calculated and the proper -- required bounds are stored in the low and high bounds. if Actual_Size > 64 then Error_Msg_Uint_1 := UI_From_Int (Actual_Size); Error_Msg_N ("size required (^) for type& too large, maximum is 64", Typ); Actual_Size := 64; end if; -- Check size against explicit given size if Has_Size_Clause (Typ) then if Actual_Size > RM_Size (Typ) then Error_Msg_Uint_1 := RM_Size (Typ); Error_Msg_Uint_2 := UI_From_Int (Actual_Size); Error_Msg_NE ("size given (^) for type& too small, minimum is ^", Size_Clause (Typ), Typ); else Actual_Size := UI_To_Int (Esize (Typ)); end if; -- Increase size to next natural boundary if no size clause given else if Actual_Size <= 8 then Actual_Size := 8; elsif Actual_Size <= 16 then Actual_Size := 16; elsif Actual_Size <= 32 then Actual_Size := 32; else Actual_Size := 64; end if; Init_Esize (Typ, Actual_Size); Adjust_Esize_For_Alignment (Typ); end if; -- If we have a base type, then expand the bounds so that they extend to -- the full width of the allocated size in bits, to avoid junk range -- checks on intermediate computations. if Base_Type (Typ) = Typ then Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1)))); Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1))); end if; -- Final step is to reanalyze the bounds using the proper type -- and set the Corresponding_Integer_Value fields of the literals. Set_Etype (Lo, Empty); Set_Analyzed (Lo, False); Analyze (Lo); -- Resolve with universal fixed if the base type, and the base type if -- it is a subtype. Note we can't resolve the base type with itself, -- that would be a reference before definition. if Typ = Btyp then Resolve (Lo, Universal_Fixed); else Resolve (Lo, Btyp); end if; -- Set corresponding integer value for bound Set_Corresponding_Integer_Value (Lo, UR_To_Uint (Realval (Lo) / Small)); -- Similar processing for high bound Set_Etype (Hi, Empty); Set_Analyzed (Hi, False); Analyze (Hi); if Typ = Btyp then Resolve (Hi, Universal_Fixed); else Resolve (Hi, Btyp); end if; Set_Corresponding_Integer_Value (Hi, UR_To_Uint (Realval (Hi) / Small)); -- Set type of range to correspond to bounds Set_Etype (Rng, Etype (Lo)); -- Set Esize to calculated size if not set already if Unknown_Esize (Typ) then Init_Esize (Typ, Actual_Size); end if; -- Set RM_Size if not already set. If already set, check value declare Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ)); begin if RM_Size (Typ) /= Uint_0 then if RM_Size (Typ) < Minsiz then Error_Msg_Uint_1 := RM_Size (Typ); Error_Msg_Uint_2 := Minsiz; Error_Msg_NE ("size given (^) for type& too small, minimum is ^", Size_Clause (Typ), Typ); end if; else Set_RM_Size (Typ, Minsiz); end if; end; end Freeze_Fixed_Point_Type; ------------------ -- Freeze_Itype -- ------------------ procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is L : List_Id; begin Set_Has_Delayed_Freeze (T); L := Freeze_Entity (T, Sloc (N)); if Is_Non_Empty_List (L) then Insert_Actions (N, L); end if; end Freeze_Itype; -------------------------- -- Freeze_Static_Object -- -------------------------- procedure Freeze_Static_Object (E : Entity_Id) is Cannot_Be_Static : exception; -- Exception raised if the type of a static object cannot be made -- static. This happens if the type depends on non-global objects. procedure Ensure_Expression_Is_SA (N : Node_Id); -- Called to ensure that an expression used as part of a type definition -- is statically allocatable, which means that the expression type is -- statically allocatable, and the expression is either static, or a -- reference to a library level constant. procedure Ensure_Type_Is_SA (Typ : Entity_Id); -- Called to mark a type as static, checking that it is possible -- to set the type as static. If it is not possible, then the -- exception Cannot_Be_Static is raised. ----------------------------- -- Ensure_Expression_Is_SA -- ----------------------------- procedure Ensure_Expression_Is_SA (N : Node_Id) is Ent : Entity_Id; begin Ensure_Type_Is_SA (Etype (N)); if Is_Static_Expression (N) then return; elsif Nkind (N) = N_Identifier then Ent := Entity (N); if Present (Ent) and then Ekind (Ent) = E_Constant and then Is_Library_Level_Entity (Ent) then return; end if; end if; raise Cannot_Be_Static; end Ensure_Expression_Is_SA; ----------------------- -- Ensure_Type_Is_SA -- ----------------------- procedure Ensure_Type_Is_SA (Typ : Entity_Id) is N : Node_Id; C : Entity_Id; begin -- If type is library level, we are all set if Is_Library_Level_Entity (Typ) then return; end if; -- We are also OK if the type already marked as statically allocated, -- which means we processed it before. if Is_Statically_Allocated (Typ) then return; end if; -- Mark type as statically allocated Set_Is_Statically_Allocated (Typ); -- Check that it is safe to statically allocate this type if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then Ensure_Expression_Is_SA (Type_Low_Bound (Typ)); Ensure_Expression_Is_SA (Type_High_Bound (Typ)); elsif Is_Array_Type (Typ) then N := First_Index (Typ); while Present (N) loop Ensure_Type_Is_SA (Etype (N)); Next_Index (N); end loop; Ensure_Type_Is_SA (Component_Type (Typ)); elsif Is_Access_Type (Typ) then if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then declare F : Entity_Id; T : constant Entity_Id := Etype (Designated_Type (Typ)); begin if T /= Standard_Void_Type then Ensure_Type_Is_SA (T); end if; F := First_Formal (Designated_Type (Typ)); while Present (F) loop Ensure_Type_Is_SA (Etype (F)); Next_Formal (F); end loop; end; else Ensure_Type_Is_SA (Designated_Type (Typ)); end if; elsif Is_Record_Type (Typ) then C := First_Entity (Typ); while Present (C) loop if Ekind (C) = E_Discriminant or else Ekind (C) = E_Component then Ensure_Type_Is_SA (Etype (C)); elsif Is_Type (C) then Ensure_Type_Is_SA (C); end if; Next_Entity (C); end loop; elsif Ekind (Typ) = E_Subprogram_Type then Ensure_Type_Is_SA (Etype (Typ)); C := First_Formal (Typ); while Present (C) loop Ensure_Type_Is_SA (Etype (C)); Next_Formal (C); end loop; else raise Cannot_Be_Static; end if; end Ensure_Type_Is_SA; -- Start of processing for Freeze_Static_Object begin Ensure_Type_Is_SA (Etype (E)); -- Reset True_Constant flag, since something strange is going on with -- the scoping here, and our simple value tracing may not be sufficient -- for this indication to be reliable. We kill the Constant_Value -- indication for the same reason. Set_Is_True_Constant (E, False); Set_Current_Value (E, Empty); exception when Cannot_Be_Static => -- If the object that cannot be static is imported or exported, -- then we give an error message saying that this object cannot -- be imported or exported. if Is_Imported (E) then Error_Msg_N ("& cannot be imported (local type is not constant)", E); -- Otherwise must be exported, something is wrong if compiler -- is marking something as statically allocated which cannot be). else pragma Assert (Is_Exported (E)); Error_Msg_N ("& cannot be exported (local type is not constant)", E); end if; end Freeze_Static_Object; ----------------------- -- Freeze_Subprogram -- ----------------------- procedure Freeze_Subprogram (E : Entity_Id) is Retype : Entity_Id; F : Entity_Id; begin -- Subprogram may not have an address clause unless it is imported if Present (Address_Clause (E)) then if not Is_Imported (E) then Error_Msg_N ("address clause can only be given " & "for imported subprogram", Name (Address_Clause (E))); end if; end if; -- Reset the Pure indication on an imported subprogram unless an -- explicit Pure_Function pragma was present. We do this because -- otherwise it is an insidious error to call a non-pure function from -- pure unit and have calls mysteriously optimized away. What happens -- here is that the Import can bypass the normal check to ensure that -- pure units call only pure subprograms. if Is_Imported (E) and then Is_Pure (E) and then not Has_Pragma_Pure_Function (E) then Set_Is_Pure (E, False); end if; -- For non-foreign convention subprograms, this is where we create -- the extra formals (for accessibility level and constrained bit -- information). We delay this till the freeze point precisely so -- that we know the convention! if not Has_Foreign_Convention (E) then Create_Extra_Formals (E); Set_Mechanisms (E); -- If this is convention Ada and a Valued_Procedure, that's odd if Ekind (E) = E_Procedure and then Is_Valued_Procedure (E) and then Convention (E) = Convention_Ada and then Warn_On_Export_Import then Error_Msg_N ("?Valued_Procedure has no effect for convention Ada", E); Set_Is_Valued_Procedure (E, False); end if; -- Case of foreign convention else Set_Mechanisms (E); -- For foreign conventions, warn about return of an -- unconstrained array. -- Note: we *do* allow a return by descriptor for the VMS case, -- though here there is probably more to be done ??? if Ekind (E) = E_Function then Retype := Underlying_Type (Etype (E)); -- If no return type, probably some other error, e.g. a -- missing full declaration, so ignore. if No (Retype) then null; -- If the return type is generic, we have emitted a warning -- earlier on, and there is nothing else to check here. Specific -- instantiations may lead to erroneous behavior. elsif Is_Generic_Type (Etype (E)) then null; elsif Is_Array_Type (Retype) and then not Is_Constrained (Retype) and then Mechanism (E) not in Descriptor_Codes and then Warn_On_Export_Import then Error_Msg_N ("?foreign convention function& should not return " & "unconstrained array", E); return; end if; end if; -- If any of the formals for an exported foreign convention -- subprogram have defaults, then emit an appropriate warning since -- this is odd (default cannot be used from non-Ada code) if Is_Exported (E) then F := First_Formal (E); while Present (F) loop if Warn_On_Export_Import and then Present (Default_Value (F)) then Error_Msg_N ("?parameter cannot be defaulted in non-Ada call", Default_Value (F)); end if; Next_Formal (F); end loop; end if; end if; -- For VMS, descriptor mechanisms for parameters are allowed only -- for imported subprograms. if OpenVMS_On_Target then if not Is_Imported (E) then F := First_Formal (E); while Present (F) loop if Mechanism (F) in Descriptor_Codes then Error_Msg_N ("descriptor mechanism for parameter not permitted", F); Error_Msg_N ("\can only be used for imported subprogram", F); end if; Next_Formal (F); end loop; end if; end if; -- Pragma Inline_Always is disallowed for dispatching subprograms -- because the address of such subprograms is saved in the dispatch -- table to support dispatching calls, and dispatching calls cannot -- be inlined. This is consistent with the restriction against using -- 'Access or 'Address on an Inline_Always subprogram. if Is_Dispatching_Operation (E) and then Is_Always_Inlined (E) then Error_Msg_N ("pragma Inline_Always not allowed for dispatching subprograms", E); end if; end Freeze_Subprogram; ---------------------- -- Is_Fully_Defined -- ---------------------- function Is_Fully_Defined (T : Entity_Id) return Boolean is begin if Ekind (T) = E_Class_Wide_Type then return Is_Fully_Defined (Etype (T)); elsif Is_Array_Type (T) then return Is_Fully_Defined (Component_Type (T)); elsif Is_Record_Type (T) and not Is_Private_Type (T) then -- Verify that the record type has no components with private types -- without completion. declare Comp : Entity_Id; begin Comp := First_Component (T); while Present (Comp) loop if not Is_Fully_Defined (Etype (Comp)) then return False; end if; Next_Component (Comp); end loop; return True; end; -- LLVM local begin else return not Is_Private_Type (T) or else Present (Full_View (Base_Type (T))); -- LLVM local end end if; end Is_Fully_Defined; --------------------------------- -- Process_Default_Expressions -- --------------------------------- procedure Process_Default_Expressions (E : Entity_Id; After : in out Node_Id) is Loc : constant Source_Ptr := Sloc (E); Dbody : Node_Id; Formal : Node_Id; Dcopy : Node_Id; Dnam : Entity_Id; begin Set_Default_Expressions_Processed (E); -- A subprogram instance and its associated anonymous subprogram share -- their signature. The default expression functions are defined in the -- wrapper packages for the anonymous subprogram, and should not be -- generated again for the instance. if Is_Generic_Instance (E) and then Present (Alias (E)) and then Default_Expressions_Processed (Alias (E)) then return; end if; Formal := First_Formal (E); while Present (Formal) loop if Present (Default_Value (Formal)) then -- We work with a copy of the default expression because we -- do not want to disturb the original, since this would mess -- up the conformance checking. Dcopy := New_Copy_Tree (Default_Value (Formal)); -- The analysis of the expression may generate insert actions, -- which of course must not be executed. We wrap those actions -- in a procedure that is not called, and later on eliminated. -- The following cases have no side-effects, and are analyzed -- directly. if Nkind (Dcopy) = N_Identifier or else Nkind (Dcopy) = N_Expanded_Name or else Nkind (Dcopy) = N_Integer_Literal or else (Nkind (Dcopy) = N_Real_Literal and then not Vax_Float (Etype (Dcopy))) or else Nkind (Dcopy) = N_Character_Literal or else Nkind (Dcopy) = N_String_Literal or else Nkind (Dcopy) = N_Null or else (Nkind (Dcopy) = N_Attribute_Reference and then Attribute_Name (Dcopy) = Name_Null_Parameter) then -- If there is no default function, we must still do a full -- analyze call on the default value, to ensure that all error -- checks are performed, e.g. those associated with static -- evaluation. Note: this branch will always be taken if the -- analyzer is turned off (but we still need the error checks). -- Note: the setting of parent here is to meet the requirement -- that we can only analyze the expression while attached to -- the tree. Really the requirement is that the parent chain -- be set, we don't actually need to be in the tree. Set_Parent (Dcopy, Declaration_Node (Formal)); Analyze (Dcopy); -- Default expressions are resolved with their own type if the -- context is generic, to avoid anomalies with private types. if Ekind (Scope (E)) = E_Generic_Package then Resolve (Dcopy); else Resolve (Dcopy, Etype (Formal)); end if; -- If that resolved expression will raise constraint error, -- then flag the default value as raising constraint error. -- This allows a proper error message on the calls. if Raises_Constraint_Error (Dcopy) then Set_Raises_Constraint_Error (Default_Value (Formal)); end if; -- If the default is a parameterless call, we use the name of -- the called function directly, and there is no body to build. elsif Nkind (Dcopy) = N_Function_Call and then No (Parameter_Associations (Dcopy)) then null; -- Else construct and analyze the body of a wrapper procedure -- that contains an object declaration to hold the expression. -- Given that this is done only to complete the analysis, it -- simpler to build a procedure than a function which might -- involve secondary stack expansion. else Dnam := Make_Defining_Identifier (Loc, New_Internal_Name ('D')); Dbody := Make_Subprogram_Body (Loc, Specification => Make_Procedure_Specification (Loc, Defining_Unit_Name => Dnam), Declarations => New_List ( Make_Object_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, New_Internal_Name ('T')), Object_Definition => New_Occurrence_Of (Etype (Formal), Loc), Expression => New_Copy_Tree (Dcopy))), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List)); Set_Scope (Dnam, Scope (E)); Set_Assignment_OK (First (Declarations (Dbody))); Set_Is_Eliminated (Dnam); Insert_After (After, Dbody); Analyze (Dbody); After := Dbody; end if; end if; Next_Formal (Formal); end loop; end Process_Default_Expressions; ---------------------------------------- -- Set_Component_Alignment_If_Not_Set -- ---------------------------------------- procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is begin -- Ignore if not base type, subtypes don't need anything if Typ /= Base_Type (Typ) then return; end if; -- Do not override existing representation if Is_Packed (Typ) then return; elsif Has_Specified_Layout (Typ) then return; elsif Component_Alignment (Typ) /= Calign_Default then return; else Set_Component_Alignment (Typ, Scope_Stack.Table (Scope_Stack.Last).Component_Alignment_Default); end if; end Set_Component_Alignment_If_Not_Set; --------------------------- -- Set_Debug_Info_Needed -- --------------------------- procedure Set_Debug_Info_Needed (T : Entity_Id) is begin if No (T) or else Needs_Debug_Info (T) or else Debug_Info_Off (T) then return; else Set_Needs_Debug_Info (T); end if; if Is_Object (T) then Set_Debug_Info_Needed (Etype (T)); elsif Is_Type (T) then Set_Debug_Info_Needed (Etype (T)); if Is_Record_Type (T) then declare Ent : Entity_Id := First_Entity (T); begin while Present (Ent) loop Set_Debug_Info_Needed (Ent); Next_Entity (Ent); end loop; end; elsif Is_Array_Type (T) then Set_Debug_Info_Needed (Component_Type (T)); declare Indx : Node_Id := First_Index (T); begin while Present (Indx) loop Set_Debug_Info_Needed (Etype (Indx)); Indx := Next_Index (Indx); end loop; end; if Is_Packed (T) then Set_Debug_Info_Needed (Packed_Array_Type (T)); end if; elsif Is_Access_Type (T) then Set_Debug_Info_Needed (Directly_Designated_Type (T)); elsif Is_Private_Type (T) then Set_Debug_Info_Needed (Full_View (T)); elsif Is_Protected_Type (T) then Set_Debug_Info_Needed (Corresponding_Record_Type (T)); end if; end if; end Set_Debug_Info_Needed; ------------------ -- Undelay_Type -- ------------------ procedure Undelay_Type (T : Entity_Id) is begin Set_Has_Delayed_Freeze (T, False); Set_Freeze_Node (T, Empty); -- Since we don't want T to have a Freeze_Node, we don't want its -- Full_View or Corresponding_Record_Type to have one either. -- ??? Fundamentally, this whole handling is a kludge. What we really -- want is to be sure that for an Itype that's part of record R and is a -- subtype of type T, that it's frozen after the later of the freeze -- points of R and T. We have no way of doing that directly, so what we -- do is force most such Itypes to be frozen as part of freezing R via -- this procedure and only delay the ones that need to be delayed -- (mostly the designated types of access types that are defined as part -- of the record). if Is_Private_Type (T) and then Present (Full_View (T)) and then Is_Itype (Full_View (T)) and then Is_Record_Type (Scope (Full_View (T))) then Undelay_Type (Full_View (T)); end if; if Is_Concurrent_Type (T) and then Present (Corresponding_Record_Type (T)) and then Is_Itype (Corresponding_Record_Type (T)) and then Is_Record_Type (Scope (Corresponding_Record_Type (T))) then Undelay_Type (Corresponding_Record_Type (T)); end if; end Undelay_Type; ------------------ -- Warn_Overlay -- ------------------ procedure Warn_Overlay (Expr : Node_Id; Typ : Entity_Id; Nam : Entity_Id) is Ent : constant Entity_Id := Entity (Nam); -- The object to which the address clause applies Init : Node_Id; Old : Entity_Id := Empty; Decl : Node_Id; begin -- No warning if address clause overlay warnings are off if not Address_Clause_Overlay_Warnings then return; end if; -- No warning if there is an explicit initialization Init := Original_Node (Expression (Declaration_Node (Ent))); if Present (Init) and then Comes_From_Source (Init) then return; end if; -- We only give the warning for non-imported entities of a type for -- which a non-null base init proc is defined (or for access types which -- have implicit null initialization). if Present (Expr) and then (Has_Non_Null_Base_Init_Proc (Typ) or else Is_Access_Type (Typ)) and then not Is_Imported (Ent) then if Nkind (Expr) = N_Attribute_Reference and then Is_Entity_Name (Prefix (Expr)) then Old := Entity (Prefix (Expr)); elsif Is_Entity_Name (Expr) and then Ekind (Entity (Expr)) = E_Constant then Decl := Declaration_Node (Entity (Expr)); if Nkind (Decl) = N_Object_Declaration and then Present (Expression (Decl)) and then Nkind (Expression (Decl)) = N_Attribute_Reference and then Is_Entity_Name (Prefix (Expression (Decl))) then Old := Entity (Prefix (Expression (Decl))); elsif Nkind (Expr) = N_Function_Call then return; end if; -- A function call (most likely to To_Address) is probably not an -- overlay, so skip warning. Ditto if the function call was inlined -- and transformed into an entity. elsif Nkind (Original_Node (Expr)) = N_Function_Call then return; end if; Decl := Next (Parent (Expr)); -- If a pragma Import follows, we assume that it is for the current -- target of the address clause, and skip the warning. if Present (Decl) and then Nkind (Decl) = N_Pragma and then Chars (Decl) = Name_Import then return; end if; if Present (Old) then Error_Msg_Node_2 := Old; Error_Msg_N ("default initialization of & may modify &?", Nam); else Error_Msg_N ("default initialization of & may modify overlaid storage?", Nam); end if; -- Add friendly warning if initialization comes from a packed array -- component. if Is_Record_Type (Typ) then declare Comp : Entity_Id; begin Comp := First_Component (Typ); while Present (Comp) loop if Nkind (Parent (Comp)) = N_Component_Declaration and then Present (Expression (Parent (Comp))) then exit; elsif Is_Array_Type (Etype (Comp)) and then Present (Packed_Array_Type (Etype (Comp))) then Error_Msg_NE ("packed array component& will be initialized to zero?", Nam, Comp); exit; else Next_Component (Comp); end if; end loop; end; end if; Error_Msg_N ("use pragma Import for & to " & "suppress initialization ('R'M B.1(24))?", Nam); end if; end Warn_Overlay; end Freeze;