Mercurial > hg > CbC > CbC_gcc
view gcc/ada/freeze.adb @ 131:84e7813d76e9
gcc-8.2
| author | mir3636 |
|---|---|
| date | Thu, 25 Oct 2018 07:37:49 +0900 |
| parents | 04ced10e8804 |
| children | 1830386684a0 |
line wrap: on
line source
------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- F R E E Z E -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2018, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Aspects; use Aspects; with Atree; use Atree; with Checks; use Checks; with Contracts; use Contracts; with Debug; use Debug; with Einfo; use Einfo; with Elists; use Elists; with Errout; use Errout; with Exp_Ch3; use Exp_Ch3; 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 Ghost; use Ghost; with Layout; use Layout; with Lib; use Lib; with Namet; use Namet; with Nlists; use Nlists; with Nmake; use Nmake; with Opt; use Opt; with Restrict; use Restrict; with Rident; use Rident; with Rtsfind; use Rtsfind; with Sem; use Sem; with Sem_Aux; use Sem_Aux; with Sem_Cat; use Sem_Cat; with Sem_Ch3; use Sem_Ch3; with Sem_Ch6; use Sem_Ch6; with Sem_Ch7; use Sem_Ch7; with Sem_Ch8; use Sem_Ch8; with Sem_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; with Warnsw; use Warnsw; 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. Also ensure any initialization is -- performed only after the object has been frozen. procedure Check_Component_Storage_Order (Encl_Type : Entity_Id; Comp : Entity_Id; ADC : Node_Id; Comp_ADC_Present : out Boolean); -- For an Encl_Type that has a Scalar_Storage_Order attribute definition -- clause, verify that the component type has an explicit and compatible -- attribute/aspect. For arrays, Comp is Empty; for records, it is the -- entity of the component under consideration. For an Encl_Type that -- does not have a Scalar_Storage_Order attribute definition clause, -- verify that the component also does not have such a clause. -- ADC is the attribute definition clause if present (or Empty). On return, -- Comp_ADC_Present is set True if the component has a Scalar_Storage_Order -- attribute definition clause. 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. This procedure also ensures that -- subsidiary entities have the flag set as required. procedure Check_Expression_Function (N : Node_Id; Nam : Entity_Id); -- When an expression function is frozen by a use of it, the expression -- itself is frozen. Check that the expression does not include references -- to deferred constants without completion. We report this at the freeze -- point of the function, to provide a better error message. -- -- In most cases the expression itself is frozen by the time the function -- itself is frozen, because the formals will be frozen by then. However, -- Attribute references to outer types are freeze points for those types; -- this routine generates the required freeze nodes for them. procedure Check_Inherited_Conditions (R : Entity_Id); -- For a tagged derived type, create wrappers for inherited operations -- that have a class-wide condition, so it can be properly rewritten if -- it involves calls to other overriding primitives. 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; N : Node_Id; 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. N has -- the same usage as in Freeze_Entity. 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 preanalyzed). 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 Set_SSO_From_Default (T : Entity_Id); -- T is a record or array type that is being frozen. If it is a base type, -- and if SSO_Set_Low/High_By_Default is set, then Reverse_Storage order -- will be set appropriately. Note that an explicit occurrence of aspect -- Scalar_Storage_Order or an explicit setting of this aspect with an -- attribute definition clause occurs, then these two flags are reset in -- any case, so call will have no effect. 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_Decl : constant Node_Id := Unit_Declaration_Node (New_S); Ent : constant Entity_Id := Defining_Entity (Decl); Body_Node : Node_Id; Renamed_Subp : Entity_Id; begin -- If the renamed subprogram is intrinsic, there is no need for a -- wrapper body: we set the alias that will be called and expanded which -- completes the declaration. This transformation is only legal if the -- renamed entity has already been elaborated. -- Note that it is legal for a renaming_as_body to rename an intrinsic -- subprogram, as long as the renaming occurs before the new entity -- is frozen (RM 8.5.4 (5)). if Nkind (Body_Decl) = N_Subprogram_Renaming_Declaration and then Is_Entity_Name (Name (Body_Decl)) then Renamed_Subp := Entity (Name (Body_Decl)); else Renamed_Subp := Empty; end if; if Present (Renamed_Subp) and then Is_Intrinsic_Subprogram (Renamed_Subp) and then (not In_Same_Source_Unit (Renamed_Subp, Ent) or else Sloc (Renamed_Subp) < Sloc (Ent)) -- We can make the renaming entity intrinsic if the renamed function -- has an interface name, or if it is one of the shift/rotate -- operations known to the compiler. and then (Present (Interface_Name (Renamed_Subp)) or else Nam_In (Chars (Renamed_Subp), Name_Rotate_Left, Name_Rotate_Right, Name_Shift_Left, Name_Shift_Right, Name_Shift_Right_Arithmetic)) then Set_Interface_Name (Ent, Interface_Name (Renamed_Subp)); if Present (Alias (Renamed_Subp)) then Set_Alias (Ent, Alias (Renamed_Subp)); else Set_Alias (Ent, Renamed_Subp); end if; Set_Is_Intrinsic_Subprogram (Ent); Set_Has_Completion (Ent); else Body_Node := Build_Renamed_Body (Decl, New_S); Insert_After (After, Body_Node); Mark_Rewrite_Insertion (Body_Node); Analyze (Body_Node); After := Body_Node; end if; 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; Pref : Node_Id := Empty; -- If the renamed entity is a primitive operation given in prefix form, -- the prefix is the target object and it has to be added as the first -- actual in the generated call. 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_Occurrence_Of (Old_S, Loc); end if; else if Nkind (Nam) = N_Selected_Component and then Present (First_Formal (Old_S)) and then (Is_Controlling_Formal (First_Formal (Old_S)) or else Is_Class_Wide_Type (Etype (First_Formal (Old_S)))) then -- Retrieve the target object, to be added as a first actual -- in the call. Call_Name := New_Occurrence_Of (Old_S, Loc); Pref := Prefix (Nam); else Call_Name := New_Copy (Name (N)); end if; -- 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 -- calls to the renamed entity. The body must be generated in any case -- for calls that may appear elsewhere. This is not done in the case -- where the subprogram is an instantiation because the actual proper -- body has not been built yet. if Ekind_In (Old_S, E_Function, E_Procedure) and then Nkind (Decl) = N_Subprogram_Declaration and then not Is_Generic_Instance (Old_S) then Set_Body_To_Inline (Decl, Old_S); end if; -- Check whether the return type is a limited view. If the subprogram -- is already frozen the generated body may have a non-limited view -- of the type, that must be used, because it is the one in the spec -- of the renaming declaration. if Ekind (Old_S) = E_Function and then Is_Entity_Name (Result_Definition (Spec)) then declare Ret_Type : constant Entity_Id := Etype (Result_Definition (Spec)); begin if Has_Non_Limited_View (Ret_Type) then Set_Result_Definition (Spec, New_Occurrence_Of (Non_Limited_View (Ret_Type), Loc)); end if; end; 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 (Pref) then declare Pref_Type : constant Entity_Id := Etype (Pref); Form_Type : constant Entity_Id := Etype (First_Formal (Old_S)); begin -- The controlling formal may be an access parameter, or the -- actual may be an access value, so adjust accordingly. if Is_Access_Type (Pref_Type) and then not Is_Access_Type (Form_Type) then Actuals := New_List (Make_Explicit_Dereference (Loc, Relocate_Node (Pref))); elsif Is_Access_Type (Form_Type) and then not Is_Access_Type (Pref) then Actuals := New_List ( Make_Attribute_Reference (Loc, Attribute_Name => Name_Access, Prefix => Relocate_Node (Pref))); else Actuals := New_List (Pref); end if; end; elsif Present (Formal) then Actuals := New_List; else Actuals := No_List; end if; if Present (Formal) then while Present (Formal) loop Append (New_Occurrence_Of (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_Simple_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_Simple_Return_Statement (Loc, Expression => New_Occurrence_Of (Old_S, Loc)); elsif Nkind (Nam) = N_Character_Literal then Call_Node := Make_Simple_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); Typ : constant Entity_Id := Etype (E); Decl : Node_Id; Expr : Node_Id; Init : Node_Id; Lhs : Node_Id; Tag_Assign : Node_Id; begin if Present (Addr) then -- For a deferred constant, the initialization value is on full view if Ekind (E) = E_Constant and then Present (Full_View (E)) then Decl := Declaration_Node (Full_View (E)); else Decl := Declaration_Node (E); end if; Expr := Expression (Addr); if Needs_Constant_Address (Decl, Typ) then Check_Constant_Address_Clause (Expr, E); -- Has_Delayed_Freeze was set on E when the address clause was -- analyzed, and must remain set because we want the address -- clause to be elaborated only after any entity it references -- has been elaborated. end if; -- If Rep_Clauses are to be ignored, remove address clause from -- list attached to entity, because it may be illegal for gigi, -- for example by breaking order of elaboration.. if Ignore_Rep_Clauses then declare Rep : Node_Id; begin Rep := First_Rep_Item (E); if Rep = Addr then Set_First_Rep_Item (E, Next_Rep_Item (Addr)); else while Present (Rep) and then Next_Rep_Item (Rep) /= Addr loop Rep := Next_Rep_Item (Rep); end loop; end if; if Present (Rep) then Set_Next_Rep_Item (Rep, Next_Rep_Item (Addr)); end if; end; -- And now remove the address clause Kill_Rep_Clause (Addr); elsif not Error_Posted (Expr) and then not Needs_Finalization (Typ) then Warn_Overlay (Expr, Typ, Name (Addr)); end if; Init := Expression (Decl); -- If a variable, or a non-imported constant, overlays a constant -- object and has an initialization value, then the initialization -- may end up writing into read-only memory. Detect the cases of -- statically identical values and remove the initialization. In -- the other cases, give a warning. We will give other warnings -- later for the variable if it is assigned. if (Ekind (E) = E_Variable or else (Ekind (E) = E_Constant and then not Is_Imported (E))) and then Overlays_Constant (E) and then Present (Init) then declare O_Ent : Entity_Id; Off : Boolean; begin Find_Overlaid_Entity (Addr, O_Ent, Off); if Ekind (O_Ent) = E_Constant and then Etype (O_Ent) = Typ and then Present (Constant_Value (O_Ent)) and then Compile_Time_Compare (Init, Constant_Value (O_Ent), Assume_Valid => True) = EQ then Set_No_Initialization (Decl); return; elsif Comes_From_Source (Init) and then Address_Clause_Overlay_Warnings then Error_Msg_Sloc := Sloc (Addr); Error_Msg_NE ("??constant& may be modified via address clause#", Decl, O_Ent); end if; end; end if; -- Remove side effects from initial expression, except in the case of -- limited build-in-place calls and aggregates, which have their own -- expansion elsewhere. This exception is necessary to avoid copying -- limited objects. if Present (Init) and then not Is_Limited_View (Typ) then -- Capture initialization value at point of declaration, and make -- explicit assignment legal, because object may be a constant. Remove_Side_Effects (Init); Lhs := New_Occurrence_Of (E, Sloc (Decl)); Set_Assignment_OK (Lhs); -- Move initialization to freeze actions, once the object has -- been frozen and the address clause alignment check has been -- performed. Append_Freeze_Action (E, Make_Assignment_Statement (Sloc (Decl), Name => Lhs, Expression => Expression (Decl))); Set_No_Initialization (Decl); -- If the object is tagged, check whether the tag must be -- reassigned explicitly. Tag_Assign := Make_Tag_Assignment (Decl); if Present (Tag_Assign) then Append_Freeze_Action (E, Tag_Assign); end if; 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 (64 bits or less) in the RM_Size -- 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 > 64 then return; -- Check for bad size clause given elsif Has_Size_Clause (T) then if RM_Size (T) < S then Error_Msg_Uint_1 := S; Error_Msg_NE ("size for& too small, minimum allowed is ^", Size_Clause (T), T); end if; -- Set size if not set already elsif Unknown_RM_Size (T) then Set_RM_Size (T, S); 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; -- Always True for elementary types, even generic formal elementary -- types. We used to return False in the latter case, but the size -- is known at compile time, even in the template, we just do not -- know the exact size but that's not the point of this routine. elsif Is_Elementary_Type (T) or else Is_Task_Type (T) then return True; -- Array types elsif Is_Array_Type (T) then -- String literals always have known size, and we can set it if Ekind (T) = E_String_Literal_Subtype then Set_Small_Size (T, Component_Size (T) * String_Literal_Length (T)); return True; -- Unconstrained types never have known at compile time size 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; -- Otherwise if component size unknown, then array size unknown 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 not greater than 64 and may be packable). declare Size : 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 Size := Size * Dim; else Size := Uint_0; end if; end if; Next_Index (Index); end loop; Set_Small_Size (T, Size); return True; end; -- For non-generic private types, go to underlying type if present 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; -- Record types 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 -- discriminated 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 or atomic -- components or independent components. -- 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) and then not Has_Atomic_Components (T) and then not Has_Independent_Components (T); Packed_Size : Uint := Uint_0; -- Size in bits so far 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_RM_Size (T) then return False; end if; end if; -- Loop through components Comp := First_Component_Or_Discriminant (T); while Present (Comp) loop 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 do not know the packed size for an atomic/VFA type -- or component, or an independent type or component, or a -- by-reference type or aliased component (because packing -- does not touch these). if Is_Atomic_Or_VFA (Ctyp) or else Is_Atomic_Or_VFA (Comp) or else Is_Independent (Ctyp) or else Is_Independent (Comp) or else Is_By_Reference_Type (Ctyp) or else Is_Aliased (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 -- substitution 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_Impl_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 deal with elementary types, small packed arrays -- if the representation is a modular type and also small -- record types (if the size is not greater than 64, but -- the condition is checked by Set_Small_Size). if Is_Elementary_Type (Ctyp) or else (Is_Array_Type (Ctyp) and then Present (Packed_Array_Impl_Type (Ctyp)) and then Is_Modular_Integer_Type (Packed_Array_Impl_Type (Ctyp))) or else Is_Record_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 Packed_Size := Packed_Size + RM_Size (Ctyp); -- 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; -- For other types we can't figure out the packed size else Packed_Size_Known := False; end if; end if; Next_Component_Or_Discriminant (Comp); end loop; if Packed_Size_Known then Set_Small_Size (T, Packed_Size); end if; return True; end; -- All other cases, size not known at compile time else return False; end if; end Size_Known; ------------------------------------- -- Static_Discriminated_Components -- ------------------------------------- function Static_Discriminated_Components (T : Entity_Id) return Boolean is Constraint : Elmt_Id; begin if Has_Discriminants (T) and then Present (Discriminant_Constraint (T)) and then Present (First_Component (T)) then 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_Component_Storage_Order -- ----------------------------------- procedure Check_Component_Storage_Order (Encl_Type : Entity_Id; Comp : Entity_Id; ADC : Node_Id; Comp_ADC_Present : out Boolean) is Comp_Base : Entity_Id; Comp_ADC : Node_Id; Encl_Base : Entity_Id; Err_Node : Node_Id; Component_Aliased : Boolean; Comp_Byte_Aligned : Boolean := False; -- Set for the record case, True if Comp is aligned on byte boundaries -- (in which case it is allowed to have different storage order). Comp_SSO_Differs : Boolean; -- Set True when the component is a nested composite, and it does not -- have the same scalar storage order as Encl_Type. begin -- Record case if Present (Comp) then Err_Node := Comp; Comp_Base := Etype (Comp); if Is_Tag (Comp) then Comp_Byte_Aligned := True; Component_Aliased := False; else -- If a component clause is present, check if the component starts -- and ends on byte boundaries. Otherwise conservatively assume it -- does so only in the case where the record is not packed. if Present (Component_Clause (Comp)) then Comp_Byte_Aligned := (Normalized_First_Bit (Comp) mod System_Storage_Unit = 0) and then (Esize (Comp) mod System_Storage_Unit = 0); else Comp_Byte_Aligned := not Is_Packed (Encl_Type); end if; Component_Aliased := Is_Aliased (Comp); end if; -- Array case else Err_Node := Encl_Type; Comp_Base := Component_Type (Encl_Type); Component_Aliased := Has_Aliased_Components (Encl_Type); end if; -- Note: the Reverse_Storage_Order flag is set on the base type, but -- the attribute definition clause is attached to the first subtype. -- Also, if the base type is incomplete or private, go to full view -- if known Encl_Base := Base_Type (Encl_Type); if Present (Underlying_Type (Encl_Base)) then Encl_Base := Underlying_Type (Encl_Base); end if; Comp_Base := Base_Type (Comp_Base); if Present (Underlying_Type (Comp_Base)) then Comp_Base := Underlying_Type (Comp_Base); end if; Comp_ADC := Get_Attribute_Definition_Clause (First_Subtype (Comp_Base), Attribute_Scalar_Storage_Order); Comp_ADC_Present := Present (Comp_ADC); -- Case of record or array component: check storage order compatibility. -- But, if the record has Complex_Representation, then it is treated as -- a scalar in the back end so the storage order is irrelevant. if (Is_Record_Type (Comp_Base) and then not Has_Complex_Representation (Comp_Base)) or else Is_Array_Type (Comp_Base) then Comp_SSO_Differs := Reverse_Storage_Order (Encl_Base) /= Reverse_Storage_Order (Comp_Base); -- Parent and extension must have same storage order if Present (Comp) and then Chars (Comp) = Name_uParent then if Comp_SSO_Differs then Error_Msg_N ("record extension must have same scalar storage order as " & "parent", Err_Node); end if; -- If component and composite SSO differs, check that component -- falls on byte boundaries and isn't bit packed. elsif Comp_SSO_Differs then -- Component SSO differs from enclosing composite: -- Reject if composite is a bit-packed array, as it is rewritten -- into an array of scalars. if Is_Bit_Packed_Array (Encl_Base) then Error_Msg_N ("type of packed array must have same scalar storage order " & "as component", Err_Node); -- Reject if not byte aligned elsif Is_Record_Type (Encl_Base) and then not Comp_Byte_Aligned then Error_Msg_N ("type of non-byte-aligned component must have same scalar " & "storage order as enclosing composite", Err_Node); -- Warn if specified only for the outer composite elsif Present (ADC) and then No (Comp_ADC) then Error_Msg_NE ("scalar storage order specified for & does not apply to " & "component?", Err_Node, Encl_Base); end if; end if; -- Enclosing type has explicit SSO: non-composite component must not -- be aliased. elsif Present (ADC) and then Component_Aliased then Error_Msg_N ("aliased component not permitted for type with explicit " & "Scalar_Storage_Order", Err_Node); end if; end Check_Component_Storage_Order; ----------------------------- -- Check_Debug_Info_Needed -- ----------------------------- procedure Check_Debug_Info_Needed (T : Entity_Id) is begin if Debug_Info_Off (T) then return; elsif Comes_From_Source (T) or else Debug_Generated_Code or else Debug_Flag_VV or else Needs_Debug_Info (T) then Set_Debug_Info_Needed (T); end if; end Check_Debug_Info_Needed; ------------------------------- -- Check_Expression_Function -- ------------------------------- procedure Check_Expression_Function (N : Node_Id; Nam : Entity_Id) is function Find_Constant (Nod : Node_Id) return Traverse_Result; -- Function to search for deferred constant ------------------- -- Find_Constant -- ------------------- function Find_Constant (Nod : Node_Id) return Traverse_Result is begin -- When a constant is initialized with the result of a dispatching -- call, the constant declaration is rewritten as a renaming of the -- displaced function result. This scenario is not a premature use of -- a constant even though the Has_Completion flag is not set. if Is_Entity_Name (Nod) and then Present (Entity (Nod)) and then Ekind (Entity (Nod)) = E_Constant and then Scope (Entity (Nod)) = Current_Scope and then Nkind (Declaration_Node (Entity (Nod))) = N_Object_Declaration and then not Is_Imported (Entity (Nod)) and then not Has_Completion (Entity (Nod)) and then not Is_Frozen (Entity (Nod)) then Error_Msg_NE ("premature use of& in call or instance", N, Entity (Nod)); elsif Nkind (Nod) = N_Attribute_Reference then Analyze (Prefix (Nod)); if Is_Entity_Name (Prefix (Nod)) and then Is_Type (Entity (Prefix (Nod))) then Freeze_Before (N, Entity (Prefix (Nod))); end if; end if; return OK; end Find_Constant; procedure Check_Deferred is new Traverse_Proc (Find_Constant); -- Local variables Decl : Node_Id; -- Start of processing for Check_Expression_Function begin Decl := Original_Node (Unit_Declaration_Node (Nam)); -- The subprogram body created for the expression function is not -- itself a freeze point. if Scope (Nam) = Current_Scope and then Nkind (Decl) = N_Expression_Function and then Nkind (N) /= N_Subprogram_Body then Check_Deferred (Expression (Decl)); end if; end Check_Expression_Function; -------------------------------- -- Check_Inherited_Conditions -- -------------------------------- procedure Check_Inherited_Conditions (R : Entity_Id) is Prim_Ops : constant Elist_Id := Primitive_Operations (R); Decls : List_Id; Needs_Wrapper : Boolean; Op_Node : Elmt_Id; Par_Prim : Entity_Id; Prim : Entity_Id; procedure Build_Inherited_Condition_Pragmas (Subp : Entity_Id); -- Build corresponding pragmas for an operation whose ancestor has -- class-wide pre/postconditions. If the operation is inherited, the -- pragmas force the creation of a wrapper for the inherited operation. -- If the ancestor is being overridden, the pragmas are constructed only -- to verify their legality, in case they contain calls to other -- primitives that may haven been overridden. --------------------------------------- -- Build_Inherited_Condition_Pragmas -- --------------------------------------- procedure Build_Inherited_Condition_Pragmas (Subp : Entity_Id) is A_Post : Node_Id; A_Pre : Node_Id; New_Prag : Node_Id; begin A_Pre := Get_Class_Wide_Pragma (Par_Prim, Pragma_Precondition); if Present (A_Pre) then New_Prag := New_Copy_Tree (A_Pre); Build_Class_Wide_Expression (Prag => New_Prag, Subp => Prim, Par_Subp => Par_Prim, Adjust_Sloc => False, Needs_Wrapper => Needs_Wrapper); if Needs_Wrapper and then not Comes_From_Source (Subp) and then Expander_Active then Append (New_Prag, Decls); end if; end if; A_Post := Get_Class_Wide_Pragma (Par_Prim, Pragma_Postcondition); if Present (A_Post) then New_Prag := New_Copy_Tree (A_Post); Build_Class_Wide_Expression (Prag => New_Prag, Subp => Prim, Par_Subp => Par_Prim, Adjust_Sloc => False, Needs_Wrapper => Needs_Wrapper); if Needs_Wrapper and then not Comes_From_Source (Subp) and then Expander_Active then Append (New_Prag, Decls); end if; end if; end Build_Inherited_Condition_Pragmas; -- Start of processing for Check_Inherited_Conditions begin Op_Node := First_Elmt (Prim_Ops); while Present (Op_Node) loop Prim := Node (Op_Node); -- Map the overridden primitive to the overriding one. This takes -- care of all overridings and is done only once. if Present (Overridden_Operation (Prim)) and then Comes_From_Source (Prim) then Par_Prim := Overridden_Operation (Prim); Update_Primitives_Mapping (Par_Prim, Prim); end if; Next_Elmt (Op_Node); end loop; -- Perform validity checks on the inherited conditions of overriding -- operations, for conformance with LSP, and apply SPARK-specific -- restrictions on inherited conditions. Op_Node := First_Elmt (Prim_Ops); while Present (Op_Node) loop Prim := Node (Op_Node); if Present (Overridden_Operation (Prim)) and then Comes_From_Source (Prim) then Par_Prim := Overridden_Operation (Prim); -- Analyze the contract items of the overridden operation, before -- they are rewritten as pragmas. Analyze_Entry_Or_Subprogram_Contract (Par_Prim); -- In GNATprove mode this is where we can collect the inherited -- conditions, because we do not create the Check pragmas that -- normally convey the the modified class-wide conditions on -- overriding operations. if GNATprove_Mode then Collect_Inherited_Class_Wide_Conditions (Prim); -- Otherwise build the corresponding pragmas to check for legality -- of the inherited condition. else Build_Inherited_Condition_Pragmas (Prim); end if; end if; Next_Elmt (Op_Node); end loop; -- Now examine the inherited operations to check whether they require -- a wrapper to handle inherited conditions that call other primitives, -- so that LSP can be verified/enforced. Op_Node := First_Elmt (Prim_Ops); Needs_Wrapper := False; while Present (Op_Node) loop Decls := Empty_List; Prim := Node (Op_Node); if not Comes_From_Source (Prim) and then Present (Alias (Prim)) then Par_Prim := Alias (Prim); -- Analyze the contract items of the parent operation, and -- determine whether a wrapper is needed. This is determined -- when the condition is rewritten in sem_prag, using the -- mapping between overridden and overriding operations built -- in the loop above. Analyze_Entry_Or_Subprogram_Contract (Par_Prim); Build_Inherited_Condition_Pragmas (Prim); end if; if Needs_Wrapper and then not Is_Abstract_Subprogram (Par_Prim) and then Expander_Active then -- We need to build a new primitive that overrides the inherited -- one, and whose inherited expression has been updated above. -- These expressions are the arguments of pragmas that are part -- of the declarations of the wrapper. The wrapper holds a single -- statement that is a call to the class-wide clone, where the -- controlling actuals are conversions to the corresponding type -- in the parent primitive: -- procedure New_Prim (F1 : T1; ...); -- procedure New_Prim (F1 : T1; ...) is -- pragma Check (Precondition, Expr); -- begin -- Par_Prim_Clone (Par_Type (F1), ...); -- end; -- If the primitive is a function the statement is a return -- statement with a call. declare Loc : constant Source_Ptr := Sloc (R); Par_R : constant Node_Id := Parent (R); New_Body : Node_Id; New_Decl : Node_Id; New_Spec : Node_Id; begin New_Spec := Build_Overriding_Spec (Par_Prim, R); New_Decl := Make_Subprogram_Declaration (Loc, Specification => New_Spec); -- Insert the declaration and the body of the wrapper after -- type declaration that generates inherited operation. For -- a null procedure, the declaration implies a null body. if Nkind (New_Spec) = N_Procedure_Specification and then Null_Present (New_Spec) then Insert_After_And_Analyze (Par_R, New_Decl); else -- Build body as wrapper to a call to the already built -- class-wide clone. New_Body := Build_Class_Wide_Clone_Call (Loc, Decls, Par_Prim, New_Spec); Insert_List_After_And_Analyze (Par_R, New_List (New_Decl, New_Body)); end if; end; Needs_Wrapper := False; end if; Next_Elmt (Op_Node); end loop; end Check_Inherited_Conditions; ---------------------------- -- 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 No (Scalar_Range (E)) or else Error_Posted (Scalar_Range (E)) then return; end if; -- The situation that is nontrivial 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; ----------------------------- -- Is_Atomic_VFA_Aggregate -- ----------------------------- function Is_Atomic_VFA_Aggregate (N : Node_Id) return Boolean is Loc : constant Source_Ptr := Sloc (N); New_N : Node_Id; Par : Node_Id; Temp : Entity_Id; Typ : Entity_Id; begin Par := Parent (N); -- Array may be qualified, so find outer context if Nkind (Par) = N_Qualified_Expression then Par := Parent (Par); end if; if not Comes_From_Source (Par) then return False; end if; case Nkind (Par) is when N_Assignment_Statement => Typ := Etype (Name (Par)); if not Is_Atomic_Or_VFA (Typ) and then not (Is_Entity_Name (Name (Par)) and then Is_Atomic_Or_VFA (Entity (Name (Par)))) then return False; end if; when N_Object_Declaration => Typ := Etype (Defining_Identifier (Par)); if not Is_Atomic_Or_VFA (Typ) and then not Is_Atomic_Or_VFA (Defining_Identifier (Par)) then return False; end if; when others => return False; end case; Temp := Make_Temporary (Loc, 'T', N); New_N := Make_Object_Declaration (Loc, Defining_Identifier => Temp, Object_Definition => New_Occurrence_Of (Typ, Loc), Expression => Relocate_Node (N)); Insert_Before (Par, New_N); Analyze (New_N); Set_Expression (Par, New_Occurrence_Of (Temp, Loc)); return True; end Is_Atomic_VFA_Aggregate; ----------------------------------------------- -- Explode_Initialization_Compound_Statement -- ----------------------------------------------- procedure Explode_Initialization_Compound_Statement (E : Entity_Id) is Init_Stmts : constant Node_Id := Initialization_Statements (E); begin if Present (Init_Stmts) and then Nkind (Init_Stmts) = N_Compound_Statement then Insert_List_Before (Init_Stmts, Actions (Init_Stmts)); -- Note that we rewrite Init_Stmts into a NULL statement, rather than -- just removing it, because Freeze_All may rely on this particular -- Node_Id still being present in the enclosing list to know where to -- stop freezing. Rewrite (Init_Stmts, Make_Null_Statement (Sloc (Init_Stmts))); Set_Initialization_Statements (E, Empty); end if; end Explode_Initialization_Compound_Statement; ---------------- -- 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 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 of 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 Push_Scope (E); Install_Visible_Declarations (E); Install_Private_Declarations (E); Freeze_All (First_Entity (E), After); End_Package_Scope (E); if Is_Generic_Instance (E) and then Has_Delayed_Freeze (E) then Set_Has_Delayed_Freeze (E, False); Expand_N_Package_Declaration (Unit_Declaration_Node (E)); end if; elsif Ekind (E) in Task_Kind and then Nkind_In (Parent (E), N_Single_Task_Declaration, N_Task_Type_Declaration) then Push_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, After); Process_Flist; end if; Next_Elmt (Prim); end loop; end; end if; if not Is_Frozen (E) then Flist := Freeze_Entity (E, After); Process_Flist; -- If already frozen, and there are delayed aspects, this is where -- we do the visibility check for these aspects (see Sem_Ch13 spec -- for a description of how we handle aspect visibility). elsif Has_Delayed_Aspects (E) then -- Retrieve the visibility to the discriminants in order to -- analyze properly the aspects. Push_Scope_And_Install_Discriminants (E); declare Ritem : Node_Id; begin Ritem := First_Rep_Item (E); while Present (Ritem) loop if Nkind (Ritem) = N_Aspect_Specification and then Entity (Ritem) = E and then Is_Delayed_Aspect (Ritem) then Check_Aspect_At_End_Of_Declarations (Ritem); end if; Ritem := Next_Rep_Item (Ritem); end loop; end; Uninstall_Discriminants_And_Pop_Scope (E); 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. Freezing will happen -- if the body comes from source, but not if it is internally -- generated, for example as the body of a type invariant. -- 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 -- The presence of a body freezes all entities previously -- declared in the current list of declarations, but this -- does not apply if the body does not come from source. -- A type invariant is transformed into a subprogram body -- which is placed at the end of the private part of the -- current package, but this body does not freeze incomplete -- types that may be declared in this private part. if (Nkind_In (Bod, N_Entry_Body, N_Package_Body, N_Protected_Body, N_Subprogram_Body, N_Task_Body) or else Nkind (Bod) in N_Body_Stub) and then List_Containing (After) = List_Containing (Parent (E)) and then Comes_From_Source (Bod) 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; -- Local variables Decl : Node_Id; E : Entity_Id; Item : Entity_Id; -- 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). -- For subprograms that are renaming_as_body, we create the wrapper -- bodies as needed. -- 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. -- 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 if Error_Posted (Decl) then Set_Has_Completion (E); else Build_And_Analyze_Renamed_Body (Decl, E, After); end if; 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; -- Freeze the default expressions of entries, entry families, and -- protected subprograms. elsif Is_Concurrent_Type (E) then Item := First_Entity (E); while Present (Item) loop if (Is_Entry (Item) or else Is_Subprogram (Item)) and then not Default_Expressions_Processed (Item) then Process_Default_Expressions (Item, After); end if; Next_Entity (Item); end loop; end if; -- Historical note: We used to create a finalization master for an -- access type whose designated type is not controlled, but contains -- private controlled compoments. This form of postprocessing is no -- longer needed because the finalization master is now created when -- the access type is frozen (see Exp_Ch3.Freeze_Type). Next_Entity (E); end loop; end Freeze_All; ----------------------- -- Freeze_And_Append -- ----------------------- procedure Freeze_And_Append (Ent : Entity_Id; N : Node_Id; Result : in out List_Id) is L : constant List_Id := Freeze_Entity (Ent, N); 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; Do_Freeze_Profile : Boolean := True) is -- Freeze T, then insert the generated Freeze nodes before the node N. -- Flag Freeze_Profile is used when T is an overloadable entity, and -- indicates whether its profile should be frozen at the same time. Freeze_Nodes : constant List_Id := Freeze_Entity (T, N, Do_Freeze_Profile); Pack : constant Entity_Id := Scope (T); begin if Ekind (T) = E_Function then Check_Expression_Function (N, T); end if; if Is_Non_Empty_List (Freeze_Nodes) then -- If the entity is a type declared in an inner package, it may be -- frozen by an outer declaration before the package itself is -- frozen. Install the package scope to analyze the freeze nodes, -- which may include generated subprograms such as predicate -- functions, etc. if Is_Type (T) and then From_Nested_Package (T) then Push_Scope (Pack); Install_Visible_Declarations (Pack); Install_Private_Declarations (Pack); Insert_Actions (N, Freeze_Nodes); End_Package_Scope (Pack); else Insert_Actions (N, Freeze_Nodes); end if; end if; end Freeze_Before; ------------------- -- Freeze_Entity -- ------------------- -- WARNING: This routine manages Ghost regions. Return statements must be -- replaced by gotos which jump to the end of the routine and restore the -- Ghost mode. function Freeze_Entity (E : Entity_Id; N : Node_Id; Do_Freeze_Profile : Boolean := True) return List_Id is Loc : constant Source_Ptr := Sloc (N); Saved_GM : constant Ghost_Mode_Type := Ghost_Mode; Saved_IGR : constant Node_Id := Ignored_Ghost_Region; -- Save the Ghost-related attributes to restore on exit Atype : Entity_Id; Comp : Entity_Id; F_Node : Node_Id; Formal : Entity_Id; Indx : Node_Id; Has_Default_Initialization : Boolean := False; -- This flag gets set to true for a variable with default initialization Result : List_Id := No_List; -- List of freezing actions, left at No_List if none Test_E : Entity_Id := E; -- This could use a comment ??? procedure Add_To_Result (Fnod : Node_Id); -- Add freeze action Fnod to list Result 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 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. procedure Check_Suspicious_Convention (Rec_Type : Entity_Id); -- Give a warning for pragma Convention with language C or C++ applied -- to a discriminated record type. This is suppressed for the unchecked -- union case, since the whole point in this case is interface C. We -- also do not generate this within instantiations, since we will have -- generated a message on the template. procedure Check_Suspicious_Modulus (Utype : Entity_Id); -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit -- integer literal without an explicit corresponding size clause. The -- caller has checked that Utype is a modular integer type. procedure Freeze_Array_Type (Arr : Entity_Id); -- Freeze array type, including freezing index and component types procedure Freeze_Object_Declaration (E : Entity_Id); -- Perform checks and generate freeze node if needed for a constant or -- variable declared by an object declaration. function Freeze_Generic_Entities (Pack : Entity_Id) return List_Id; -- Create Freeze_Generic_Entity nodes for types declared in a generic -- package. Recurse on inner generic packages. function Freeze_Profile (E : Entity_Id) return Boolean; -- Freeze formals and return type of subprogram. If some type in the -- profile is incomplete and we are in an instance, freezing of the -- entity will take place elsewhere, and the function returns False. procedure Freeze_Record_Type (Rec : Entity_Id); -- Freeze record type, including freezing component types, and freezing -- primitive operations if this is a tagged type. function Has_Boolean_Aspect_Import (E : Entity_Id) return Boolean; -- Determine whether an arbitrary entity is subject to Boolean aspect -- Import and its value is specified as True. procedure Inherit_Freeze_Node (Fnod : Node_Id; Typ : Entity_Id); -- Set type Typ's freeze node to refer to Fnode. This routine ensures -- that any attributes attached to Typ's original node are preserved. procedure Wrap_Imported_Subprogram (E : Entity_Id); -- If E is an entity for an imported subprogram with pre/post-conditions -- then this procedure will create a wrapper to ensure that proper run- -- time checking of the pre/postconditions. See body for details. ------------------- -- Add_To_Result -- ------------------- procedure Add_To_Result (Fnod : Node_Id) is begin -- The Ghost mode of the enclosing context is ignored, while the -- entity being frozen is living. Insert the freezing action prior -- to the start of the enclosing ignored Ghost region. As a result -- the freezeing action will be preserved when the ignored Ghost -- context is eliminated. if Saved_GM = Ignore and then Ghost_Mode /= Ignore and then Present (Ignored_Ghost_Region) then Insert_Action (Ignored_Ghost_Region, Fnod); -- Otherwise add the freezing action to the result list else Append_New_To (Result, Fnod); end if; end Add_To_Result; ---------------------------- -- 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 Is_Aliased_View_Of_Type (Typ : Entity_Id) return Boolean; -- Determine whether Typ is compatible with the rules for aliased -- views of types as defined in RM 3.10 in the various dialects. function Process (N : Node_Id) return Traverse_Result; -- Process routine to apply check to given node ----------------------------- -- Is_Aliased_View_Of_Type -- ----------------------------- function Is_Aliased_View_Of_Type (Typ : Entity_Id) return Boolean is Typ_Decl : constant Node_Id := Parent (Typ); begin -- Common case if Nkind (Typ_Decl) = N_Full_Type_Declaration and then Limited_Present (Type_Definition (Typ_Decl)) then return True; -- The following paragraphs describe what a legal aliased view of -- a type is in the various dialects of Ada. -- Ada 95 -- The current instance of a limited type, and a formal parameter -- or generic formal object of a tagged type. -- Ada 95 limited type -- * Type with reserved word "limited" -- * A protected or task type -- * A composite type with limited component elsif Ada_Version <= Ada_95 then return Is_Limited_Type (Typ); -- Ada 2005 -- The current instance of a limited tagged type, a protected -- type, a task type, or a type that has the reserved word -- "limited" in its full definition ... a formal parameter or -- generic formal object of a tagged type. -- Ada 2005 limited type -- * Type with reserved word "limited", "synchronized", "task" -- or "protected" -- * A composite type with limited component -- * A derived type whose parent is a non-interface limited type elsif Ada_Version = Ada_2005 then return (Is_Limited_Type (Typ) and then Is_Tagged_Type (Typ)) or else (Is_Derived_Type (Typ) and then not Is_Interface (Etype (Typ)) and then Is_Limited_Type (Etype (Typ))); -- Ada 2012 and beyond -- The current instance of an immutably limited type ... a formal -- parameter or generic formal object of a tagged type. -- Ada 2012 limited type -- * Type with reserved word "limited", "synchronized", "task" -- or "protected" -- * A composite type with limited component -- * A derived type whose parent is a non-interface limited type -- * An incomplete view -- Ada 2012 immutably limited type -- * Explicitly limited record type -- * Record extension with "limited" present -- * Non-formal limited private type that is either tagged -- or has at least one access discriminant with a default -- expression -- * Task type, protected type or synchronized interface -- * Type derived from immutably limited type else return Is_Immutably_Limited_Type (Typ) or else Is_Incomplete_Type (Typ); end if; end Is_Aliased_View_Of_Type; ------------- -- Process -- ------------- function Process (N : Node_Id) return Traverse_Result is begin case Nkind (N) is when N_Attribute_Reference => if Nam_In (Attribute_Name (N), Name_Access, Name_Unchecked_Access) and then Is_Entity_Name (Prefix (N)) and then Is_Type (Entity (Prefix (N))) and then Entity (Prefix (N)) = E then if Ada_Version < Ada_2012 then Error_Msg_N ("current instance must be a limited type", Prefix (N)); else Error_Msg_N ("current instance must be an immutably limited " & "type (RM-2012, 7.5 (8.1/3))", Prefix (N)); end if; return Abandon; else return OK; end if; when others => return OK; end case; end Process; procedure Traverse is new Traverse_Proc (Process); -- Local variables Rec_Type : constant Entity_Id := Scope (Defining_Identifier (Comp_Decl)); -- Start of processing for Check_Current_Instance begin if not Is_Aliased_View_Of_Type (Rec_Type) then Traverse (Comp_Decl); end if; end Check_Current_Instance; --------------------------------- -- Check_Suspicious_Convention -- --------------------------------- procedure Check_Suspicious_Convention (Rec_Type : Entity_Id) is begin if Has_Discriminants (Rec_Type) and then Is_Base_Type (Rec_Type) and then not Is_Unchecked_Union (Rec_Type) and then (Convention (Rec_Type) = Convention_C or else Convention (Rec_Type) = Convention_CPP) and then Comes_From_Source (Rec_Type) and then not In_Instance and then not Has_Warnings_Off (Rec_Type) then declare Cprag : constant Node_Id := Get_Rep_Pragma (Rec_Type, Name_Convention); A2 : Node_Id; begin if Present (Cprag) then A2 := Next (First (Pragma_Argument_Associations (Cprag))); if Convention (Rec_Type) = Convention_C then Error_Msg_N ("?x?discriminated record has no direct equivalent in " & "C", A2); else Error_Msg_N ("?x?discriminated record has no direct equivalent in " & "C++", A2); end if; Error_Msg_NE ("\?x?use of convention for type& is dubious", A2, Rec_Type); end if; end; end if; end Check_Suspicious_Convention; ------------------------------ -- Check_Suspicious_Modulus -- ------------------------------ procedure Check_Suspicious_Modulus (Utype : Entity_Id) is Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype)); begin if not Warn_On_Suspicious_Modulus_Value then return; end if; if Nkind (Decl) = N_Full_Type_Declaration then declare Tdef : constant Node_Id := Type_Definition (Decl); begin if Nkind (Tdef) = N_Modular_Type_Definition then declare Modulus : constant Node_Id := Original_Node (Expression (Tdef)); begin if Nkind (Modulus) = N_Integer_Literal then declare Modv : constant Uint := Intval (Modulus); Sizv : constant Uint := RM_Size (Utype); begin -- First case, modulus and size are the same. This -- happens if you have something like mod 32, with -- an explicit size of 32, this is for sure a case -- where the warning is given, since it is seems -- very unlikely that someone would want e.g. a -- five bit type stored in 32 bits. It is much -- more likely they wanted a 32-bit type. if Modv = Sizv then null; -- Second case, the modulus is 32 or 64 and no -- size clause is present. This is a less clear -- case for giving the warning, but in the case -- of 32/64 (5-bit or 6-bit types) these seem rare -- enough that it is a likely error (and in any -- case using 2**5 or 2**6 in these cases seems -- clearer. We don't include 8 or 16 here, simply -- because in practice 3-bit and 4-bit types are -- more common and too many false positives if -- we warn in these cases. elsif not Has_Size_Clause (Utype) and then (Modv = Uint_32 or else Modv = Uint_64) then null; -- No warning needed else return; end if; -- If we fall through, give warning Error_Msg_Uint_1 := Modv; Error_Msg_N ("?M?2 '*'*^' may have been intended here", Modulus); end; end if; end; end if; end; end if; end Check_Suspicious_Modulus; ----------------------- -- Freeze_Array_Type -- ----------------------- procedure Freeze_Array_Type (Arr : Entity_Id) is FS : constant Entity_Id := First_Subtype (Arr); Ctyp : constant Entity_Id := Component_Type (Arr); Clause : Entity_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, N, Result); Indx := First_Index (Arr); while Present (Indx) loop Freeze_And_Append (Etype (Indx), N, 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 (Arr) = E_Array_Type then -- Deal with default setting of reverse storage order Set_SSO_From_Default (Arr); -- Propagate flags for component type if Is_Controlled (Component_Type (Arr)) or else Has_Controlled_Component (Ctyp) then Set_Has_Controlled_Component (Arr); end if; if Has_Unchecked_Union (Component_Type (Arr)) then Set_Has_Unchecked_Union (Arr); end if; -- The array type requires its own invariant procedure in order to -- verify the component invariant over all elements. In GNATprove -- mode, the component invariants are checked by other means. They -- should not be added to the array type invariant procedure, so -- that the procedure can be used to check the array type -- invariants if any. if Has_Invariants (Component_Type (Arr)) and then not GNATprove_Mode then Set_Has_Own_Invariants (Arr); -- The array type is an implementation base type. Propagate the -- same property to the first subtype. if Is_Itype (Arr) then Set_Has_Own_Invariants (First_Subtype (Arr)); end if; end if; -- Warn for pragma Pack overriding foreign convention if Has_Foreign_Convention (Ctyp) and then Has_Pragma_Pack (Arr) then declare CN : constant Name_Id := Get_Convention_Name (Convention (Ctyp)); PP : constant Node_Id := Get_Pragma (First_Subtype (Arr), Pragma_Pack); begin if Present (PP) then Error_Msg_Name_1 := CN; Error_Msg_Sloc := Sloc (Arr); Error_Msg_N ("pragma Pack affects convention % components #??", PP); Error_Msg_Name_1 := CN; Error_Msg_N ("\array components may not have % compatible " & "representation??", PP); end if; end; 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 of the -- representation aspects involved are type-related. -- This is not just an optimization, if we start processing the -- subtypes, they interfere 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 (Arr) or else Has_Pragma_Pack (Arr)) and then Known_Static_RM_Size (Ctyp) and then not Has_Component_Size_Clause (Arr) then Csiz := UI_Max (RM_Size (Ctyp), 1); elsif Known_Component_Size (Arr) then Csiz := Component_Size (Arr); 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 size (the -- padded type cases). 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; -- Case of component size that may result in bit packing if 1 <= Csiz and then Csiz <= 64 then declare Ent : constant Entity_Id := First_Subtype (Arr); Pack_Pragma : constant Node_Id := Get_Rep_Pragma (Ent, Name_Pack); Comp_Size_C : constant Node_Id := Get_Attribute_Definition_Clause (Ent, Attribute_Component_Size); begin -- Warn if we have pack and component size so that the -- pack is ignored. -- Note: here we must check for the presence of a -- component size before checking for a Pack pragma to -- deal with the case where the array type is a derived -- type whose parent is currently private. if Present (Comp_Size_C) and then Has_Pragma_Pack (Ent) and then Warn_On_Redundant_Constructs then Error_Msg_Sloc := Sloc (Comp_Size_C); Error_Msg_NE ("?r?pragma Pack for& ignored!", Pack_Pragma, Ent); Error_Msg_N ("\?r?explicit component size given#!", Pack_Pragma); Set_Is_Packed (Base_Type (Ent), False); Set_Is_Bit_Packed_Array (Base_Type (Ent), False); end if; -- Set component size if not already set by a component -- size clause. if not Present (Comp_Size_C) then Set_Component_Size (Arr, Csiz); end if; -- Check for base type of 8, 16, 32 bits, where an -- unsigned subtype has a length one less than the -- base type (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 (Arr) and then not Present (Comp_Size_C) 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; if Present (Pack_Pragma) then Error_Msg_N ("??pragma Pack causes component size to be ^!", Pack_Pragma); Error_Msg_N ("\??use Component_Size to set desired value!", Pack_Pragma); end if; end if; -- Bit packing is never needed for 8, 16, 32, 64 if Addressable (Csiz) then -- If the Esize of the component is known and equal to -- the component size then even packing is not needed. if Known_Static_Esize (Component_Type (Arr)) and then Esize (Component_Type (Arr)) = Csiz then -- Here the array was requested to be packed, but -- the packing request had no effect whatsoever, -- so flag Is_Packed is reset. -- Note: semantically this means that we lose track -- of the fact that a derived type inherited pragma -- Pack that was non-effective, but that is 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 (Arr), False); Set_Has_Non_Standard_Rep (Base_Type (Arr), False); else Set_Is_Packed (Base_Type (Arr), True); Set_Has_Non_Standard_Rep (Base_Type (Arr), True); end if; Set_Is_Bit_Packed_Array (Base_Type (Arr), False); -- Bit packing is not needed for multiples of the storage -- unit if the type is composite because the back end can -- byte pack composite types. elsif Csiz mod System_Storage_Unit = 0 and then Is_Composite_Type (Ctyp) then Set_Is_Packed (Base_Type (Arr), True); Set_Has_Non_Standard_Rep (Base_Type (Arr), True); Set_Is_Bit_Packed_Array (Base_Type (Arr), False); -- In all other cases, bit packing is needed else Set_Is_Packed (Base_Type (Arr), True); Set_Has_Non_Standard_Rep (Base_Type (Arr), True); Set_Is_Bit_Packed_Array (Base_Type (Arr), True); end if; end; end if; end; -- Check for Aliased or Atomic_Components/Atomic/VFA with -- unsuitable packing or explicit component size clause given. if (Has_Aliased_Components (Arr) or else Has_Atomic_Components (Arr) or else Is_Atomic_Or_VFA (Ctyp)) and then (Has_Component_Size_Clause (Arr) or else Is_Packed (Arr)) then Alias_Atomic_Check : declare procedure Complain_CS (T : String); -- Outputs error messages for incorrect CS clause or pragma -- Pack for aliased or atomic/VFA components (T is "aliased" -- or "atomic/vfa"); ----------------- -- Complain_CS -- ----------------- procedure Complain_CS (T : String) is begin if Has_Component_Size_Clause (Arr) then Clause := Get_Attribute_Definition_Clause (FS, Attribute_Component_Size); Error_Msg_N ("incorrect component size for " & T & " components", Clause); Error_Msg_Uint_1 := Esize (Ctyp); Error_Msg_N ("\only allowed value is^", Clause); else Error_Msg_N ("cannot pack " & T & " components", Get_Rep_Pragma (FS, Name_Pack)); end if; end Complain_CS; -- Start of processing for Alias_Atomic_Check begin -- If object size of component type isn't known, we cannot -- be sure so we defer to the back end. if not Known_Static_Esize (Ctyp) then null; -- Case where component size has no effect. First check for -- object size of component type multiple of the storage -- unit size. elsif Esize (Ctyp) mod System_Storage_Unit = 0 -- OK in both packing case and component size case if RM -- size is known and static and same as the object size. and then ((Known_Static_RM_Size (Ctyp) and then Esize (Ctyp) = RM_Size (Ctyp)) -- Or if we have an explicit component size clause and -- the component size and object size are equal. or else (Has_Component_Size_Clause (Arr) and then Component_Size (Arr) = Esize (Ctyp))) then null; elsif Has_Aliased_Components (Arr) then Complain_CS ("aliased"); elsif Has_Atomic_Components (Arr) or else Is_Atomic (Ctyp) then Complain_CS ("atomic"); elsif Is_Volatile_Full_Access (Ctyp) then Complain_CS ("volatile full access"); end if; end Alias_Atomic_Check; end if; -- Check for Independent_Components/Independent with unsuitable -- packing or explicit component size clause given. if (Has_Independent_Components (Arr) or else Is_Independent (Ctyp)) and then (Has_Component_Size_Clause (Arr) or else Is_Packed (Arr)) then begin -- If object size of component type isn't known, we cannot -- be sure so we defer to the back end. if not Known_Static_Esize (Ctyp) then null; -- Case where component size has no effect. First check for -- object size of component type multiple of the storage -- unit size. elsif Esize (Ctyp) mod System_Storage_Unit = 0 -- OK in both packing case and component size case if RM -- size is known and multiple of the storage unit size. and then ((Known_Static_RM_Size (Ctyp) and then RM_Size (Ctyp) mod System_Storage_Unit = 0) -- Or if we have an explicit component size clause and -- the component size is larger than the object size. or else (Has_Component_Size_Clause (Arr) and then Component_Size (Arr) >= Esize (Ctyp))) then null; else if Has_Component_Size_Clause (Arr) then Clause := Get_Attribute_Definition_Clause (FS, Attribute_Component_Size); Error_Msg_N ("incorrect component size for " & "independent components", Clause); Error_Msg_Uint_1 := Esize (Ctyp); Error_Msg_N ("\minimum allowed is^", Clause); else Error_Msg_N ("cannot pack independent components", Get_Rep_Pragma (FS, Name_Pack)); end if; end if; end; end if; -- Warn for case of atomic type Clause := Get_Rep_Pragma (FS, Name_Atomic); if Present (Clause) and then not Addressable (Component_Size (FS)) then Error_Msg_NE ("non-atomic components of type& may not be " & "accessible by separate tasks??", Clause, Arr); if Has_Component_Size_Clause (Arr) then Error_Msg_Sloc := Sloc (Get_Attribute_Definition_Clause (FS, Attribute_Component_Size)); Error_Msg_N ("\because of component size clause#??", Clause); elsif Has_Pragma_Pack (Arr) then Error_Msg_Sloc := Sloc (Get_Rep_Pragma (FS, Name_Pack)); Error_Msg_N ("\because of pragma Pack#??", Clause); end if; end if; -- Check for scalar storage order declare Dummy : Boolean; begin Check_Component_Storage_Order (Encl_Type => Arr, Comp => Empty, ADC => Get_Attribute_Definition_Clause (First_Subtype (Arr), Attribute_Scalar_Storage_Order), Comp_ADC_Present => Dummy); end; -- Processing that is done only for subtypes else -- Acquire alignment from base type if Unknown_Alignment (Arr) then Set_Alignment (Arr, Alignment (Base_Type (Arr))); Adjust_Esize_Alignment (Arr); end if; end if; -- Specific checks for bit-packed arrays if Is_Bit_Packed_Array (Arr) then -- Check number of elements for bit-packed arrays that come from -- source and have compile time known ranges. The bit-packed -- arrays circuitry does not support arrays with more than -- Integer'Last + 1 elements, and when this restriction is -- violated, causes incorrect data access. -- For the case where this is not compile time known, a run-time -- check should be generated??? if Comes_From_Source (Arr) and then Is_Constrained (Arr) then declare Elmts : Uint; Index : Node_Id; Ilen : Node_Id; Ityp : Entity_Id; begin Elmts := Uint_1; Index := First_Index (Arr); while Present (Index) loop Ityp := Etype (Index); -- Never generate an error if any index is of a generic -- type. We will check this in instances. if Is_Generic_Type (Ityp) then Elmts := Uint_0; exit; end if; Ilen := Make_Attribute_Reference (Loc, Prefix => New_Occurrence_Of (Ityp, Loc), Attribute_Name => Name_Range_Length); Analyze_And_Resolve (Ilen); -- No attempt is made to check number of elements if not -- compile time known. if Nkind (Ilen) /= N_Integer_Literal then Elmts := Uint_0; exit; end if; Elmts := Elmts * Intval (Ilen); Next_Index (Index); end loop; if Elmts > Intval (High_Bound (Scalar_Range (Standard_Integer))) + 1 then Error_Msg_N ("bit packed array type may not have " & "more than Integer''Last+1 elements", Arr); end if; end; end if; -- Check size if Known_RM_Size (Arr) then declare SizC : constant Node_Id := Size_Clause (Arr); Discard : Boolean; begin -- It is not clear if it is possible to have no size clause -- at this stage, but it is not worth worrying about. Post -- 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), Arr, RM_Size (Arr), Discard); else Check_Size (Arr, Arr, RM_Size (Arr), Discard); end if; end; end if; end if; -- 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 (Arr)); Set_Is_Packed (Base_Type (Arr)); end if; Set_Component_Alignment_If_Not_Set (Arr); -- If the array is packed and bit-packed or packed to eliminate holes -- in the non-contiguous enumeration index types, 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 (Arr) and then (Is_Bit_Packed_Array (Arr) or else Non_Standard_Enum) and then Ekind (Arr) /= E_String_Literal_Subtype then Create_Packed_Array_Impl_Type (Arr); Freeze_And_Append (Packed_Array_Impl_Type (Arr), N, Result); -- Make sure that we have the necessary routines to implement the -- packing, and complain now if not. Note that we only test this -- for constrained array types. if Is_Constrained (Arr) and then Is_Bit_Packed_Array (Arr) and then Present (Packed_Array_Impl_Type (Arr)) and then Is_Array_Type (Packed_Array_Impl_Type (Arr)) then declare CS : constant Uint := Component_Size (Arr); RE : constant RE_Id := Get_Id (UI_To_Int (CS)); begin if RE /= RE_Null and then not RTE_Available (RE) then Error_Msg_CRT ("packing of " & UI_Image (CS) & "-bit components", First_Subtype (Etype (Arr))); -- Cancel the packing Set_Is_Packed (Base_Type (Arr), False); Set_Is_Bit_Packed_Array (Base_Type (Arr), False); Set_Packed_Array_Impl_Type (Arr, Empty); goto Skip_Packed; end if; end; end if; -- Size information of packed array type is copied to the array -- type, since this is really the representation. But do not -- override explicit existing size values. If the ancestor subtype -- is constrained the Packed_Array_Impl_Type will be inherited -- from it, but the size may have been provided already, and -- must not be overridden either. if not Has_Size_Clause (Arr) and then (No (Ancestor_Subtype (Arr)) or else not Has_Size_Clause (Ancestor_Subtype (Arr))) then Set_Esize (Arr, Esize (Packed_Array_Impl_Type (Arr))); Set_RM_Size (Arr, RM_Size (Packed_Array_Impl_Type (Arr))); end if; if not Has_Alignment_Clause (Arr) then Set_Alignment (Arr, Alignment (Packed_Array_Impl_Type (Arr))); end if; end if; <<Skip_Packed>> -- For non-packed arrays set the alignment of the array to the -- alignment of the component type if it is unknown. Skip this -- in atomic/VFA case (atomic/VFA arrays may need larger alignments). if not Is_Packed (Arr) and then Unknown_Alignment (Arr) and then Known_Alignment (Ctyp) and then Known_Static_Component_Size (Arr) and then Known_Static_Esize (Ctyp) and then Esize (Ctyp) = Component_Size (Arr) and then not Is_Atomic_Or_VFA (Arr) then Set_Alignment (Arr, Alignment (Component_Type (Arr))); end if; -- A Ghost type cannot have a component of protected or task type -- (SPARK RM 6.9(19)). if Is_Ghost_Entity (Arr) and then Is_Concurrent_Type (Ctyp) then Error_Msg_N ("ghost array type & cannot have concurrent component type", Arr); end if; end Freeze_Array_Type; ------------------------------- -- Freeze_Object_Declaration -- ------------------------------- procedure Freeze_Object_Declaration (E : Entity_Id) is procedure Check_Large_Modular_Array (Typ : Entity_Id); -- Check that the size of array type Typ can be computed without -- overflow, and generates a Storage_Error otherwise. This is only -- relevant for array types whose index is a (mod 2**64) type, where -- wrap-around arithmetic might yield a meaningless value for the -- length of the array, or its corresponding attribute. ------------------------------- -- Check_Large_Modular_Array -- ------------------------------- procedure Check_Large_Modular_Array (Typ : Entity_Id) is Obj_Loc : constant Source_Ptr := Sloc (E); Idx_Typ : Entity_Id; begin -- Nothing to do when expansion is disabled because this routine -- generates a runtime check. if not Expander_Active then return; -- Nothing to do for String literal subtypes because their index -- cannot be a modular type. elsif Ekind (Typ) = E_String_Literal_Subtype then return; -- Nothing to do for an imported object because the object will -- be created on the exporting side. elsif Is_Imported (E) then return; -- Nothing to do for unconstrained array types. This case arises -- when the object declaration is illegal. elsif not Is_Constrained (Typ) then return; end if; Idx_Typ := Etype (First_Index (Typ)); -- To prevent arithmetic overflow with large values, we raise -- Storage_Error under the following guard: -- -- (Arr'Last / 2 - Arr'First / 2) > (2 ** 30) -- -- This takes care of the boundary case, but it is preferable to -- use a smaller limit, because even on 64-bit architectures an -- array of more than 2 ** 30 bytes is likely to raise -- Storage_Error. if Is_Modular_Integer_Type (Idx_Typ) and then RM_Size (Idx_Typ) = RM_Size (Standard_Long_Long_Integer) then Insert_Action (Declaration_Node (E), Make_Raise_Storage_Error (Obj_Loc, Condition => Make_Op_Ge (Obj_Loc, Left_Opnd => Make_Op_Subtract (Obj_Loc, Left_Opnd => Make_Op_Divide (Obj_Loc, Left_Opnd => Make_Attribute_Reference (Obj_Loc, Prefix => New_Occurrence_Of (Typ, Obj_Loc), Attribute_Name => Name_Last), Right_Opnd => Make_Integer_Literal (Obj_Loc, Uint_2)), Right_Opnd => Make_Op_Divide (Obj_Loc, Left_Opnd => Make_Attribute_Reference (Obj_Loc, Prefix => New_Occurrence_Of (Typ, Obj_Loc), Attribute_Name => Name_First), Right_Opnd => Make_Integer_Literal (Obj_Loc, Uint_2))), Right_Opnd => Make_Integer_Literal (Obj_Loc, (Uint_2 ** 30))), Reason => SE_Object_Too_Large)); end if; end Check_Large_Modular_Array; -- Local variables Typ : constant Entity_Id := Etype (E); Def : Node_Id; -- Start of processing for Freeze_Object_Declaration begin -- Abstract type allowed only for C++ imported variables or constants -- Note: we inhibit this check for objects that do not come from -- source because there is at least one case (the expansion of -- x'Class'Input where x is abstract) where we legitimately -- generate an abstract object. if Is_Abstract_Type (Typ) and then Comes_From_Source (Parent (E)) and then not (Is_Imported (E) and then Is_CPP_Class (Typ)) then Def := Object_Definition (Parent (E)); Error_Msg_N ("type of object cannot be abstract", Def); if Is_CPP_Class (Etype (E)) then Error_Msg_NE ("\} may need a cpp_constructor", Def, Typ); elsif Present (Expression (Parent (E))) then Error_Msg_N -- CODEFIX ("\maybe a class-wide type was meant", Def); end if; end if; -- 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 that it is valid and if need -- be move initialization to the freeze node. Check_Address_Clause (E); -- Similar processing is needed for aspects that may affect object -- layout, like Alignment, if there is an initialization expression. -- We don't do this if there is a pragma Linker_Section, because it -- would prevent the back end from statically initializing the -- object; we don't want elaboration code in that case. if Has_Delayed_Aspects (E) and then Expander_Active and then Is_Array_Type (Typ) and then Present (Expression (Parent (E))) and then No (Linker_Section_Pragma (E)) then declare Decl : constant Node_Id := Parent (E); Lhs : constant Node_Id := New_Occurrence_Of (E, Loc); begin -- Capture initialization value at point of declaration, and -- make explicit assignment legal, because object may be a -- constant. Remove_Side_Effects (Expression (Decl)); Set_Assignment_OK (Lhs); -- Move initialization to freeze actions Append_Freeze_Action (E, Make_Assignment_Statement (Loc, Name => Lhs, Expression => Expression (Decl))); Set_No_Initialization (Decl); -- Set_Is_Frozen (E, False); end; end if; -- Reset Is_True_Constant for non-constant aliased object. We -- consider that the fact that a non-constant object is aliased may -- indicate that some funny business is going on, e.g. an aliased -- object is passed by reference to a procedure which captures the -- address of the object, which is later used to assign a new value, -- even though the compiler thinks that it is not modified. Such -- code is highly dubious, but we choose to make it "work" for -- non-constant aliased objects. -- Note that we used to do this for all aliased objects, whether or -- not constant, but this caused anomalies down the line because we -- ended up with static objects that were not Is_True_Constant. Not -- resetting Is_True_Constant for (aliased) constant objects ensures -- that this anomaly never occurs. -- However, we don't do that for internal entities. We figure that if -- we deliberately set Is_True_Constant for an internal entity, e.g. -- a dispatch table entry, then we mean it. if Ekind (E) /= E_Constant and then (Is_Aliased (E) or else Is_Aliased (Typ)) and then not Is_Internal_Name (Chars (E)) then Set_Is_True_Constant (E, False); end if; -- If the object needs any kind of default initialization, an error -- must be issued if No_Default_Initialization applies. The check -- doesn't apply to imported objects, which are not ever default -- initialized, and is why the check is deferred until freezing, at -- which point we know if Import applies. Deferred constants are also -- exempted from this test because their completion is explicit, or -- through an import pragma. if Ekind (E) = E_Constant and then Present (Full_View (E)) then null; elsif Comes_From_Source (E) and then not Is_Imported (E) and then not Has_Init_Expression (Declaration_Node (E)) and then ((Has_Non_Null_Base_Init_Proc (Typ) and then not No_Initialization (Declaration_Node (E)) and then not Initialization_Suppressed (Typ)) or else (Needs_Simple_Initialization (Typ) and then not Is_Internal (E))) then Has_Default_Initialization := True; Check_Restriction (No_Default_Initialization, Declaration_Node (E)); end if; -- Check that a Thread_Local_Storage variable does not have default -- initialization, and any explicit initialization must either be the -- null constant or a static constant. if Has_Pragma_Thread_Local_Storage (E) then declare Decl : constant Node_Id := Declaration_Node (E); begin if Has_Default_Initialization or else (Has_Init_Expression (Decl) and then (No (Expression (Decl)) or else not (Is_OK_Static_Expression (Expression (Decl)) or else Nkind (Expression (Decl)) = N_Null))) then if Nkind (Expression (Decl)) = N_Aggregate and then Compile_Time_Known_Aggregate (Expression (Decl)) then null; else Error_Msg_NE ("Thread_Local_Storage variable& is improperly " & "initialized", Decl, E); Error_Msg_NE ("\only allowed initialization is explicit NULL, " & "static expression or static aggregate", Decl, E); end if; end if; end; end if; -- 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; -- For source objects that are not Imported and are library level, if -- no linker section pragma was given inherit the appropriate linker -- section from the corresponding type. if Comes_From_Source (E) and then not Is_Imported (E) and then Is_Library_Level_Entity (E) and then No (Linker_Section_Pragma (E)) then Set_Linker_Section_Pragma (E, Linker_Section_Pragma (Typ)); end if; -- For convention C objects of an enumeration type, warn if the size -- is not integer size and no explicit size given. Skip warning for -- Boolean and Character, and assume programmer expects 8-bit sizes -- for these cases. if (Convention (E) = Convention_C or else Convention (E) = Convention_CPP) and then Is_Enumeration_Type (Typ) and then not Is_Character_Type (Typ) and then not Is_Boolean_Type (Typ) and then Esize (Typ) < Standard_Integer_Size and then not Has_Size_Clause (E) then Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size); Error_Msg_N ("??convention C enumeration object has size less than ^", E); Error_Msg_N ("\??use explicit size clause to set size", E); end if; if Is_Array_Type (Typ) then Check_Large_Modular_Array (Typ); end if; end Freeze_Object_Declaration; ----------------------------- -- Freeze_Generic_Entities -- ----------------------------- function Freeze_Generic_Entities (Pack : Entity_Id) return List_Id is E : Entity_Id; F : Node_Id; Flist : List_Id; begin Flist := New_List; E := First_Entity (Pack); while Present (E) loop if Is_Type (E) and then not Is_Generic_Type (E) then F := Make_Freeze_Generic_Entity (Sloc (Pack)); Set_Entity (F, E); Append_To (Flist, F); elsif Ekind (E) = E_Generic_Package then Append_List_To (Flist, Freeze_Generic_Entities (E)); end if; Next_Entity (E); end loop; return Flist; end Freeze_Generic_Entities; -------------------- -- Freeze_Profile -- -------------------- function Freeze_Profile (E : Entity_Id) return Boolean is F_Type : Entity_Id; R_Type : Entity_Id; Warn_Node : Node_Id; begin -- Loop through formals Formal := First_Formal (E); while Present (Formal) loop F_Type := Etype (Formal); -- AI05-0151: incomplete types can appear in a profile. By the -- time the entity is frozen, the full view must be available, -- unless it is a limited view. if Is_Incomplete_Type (F_Type) and then Present (Full_View (F_Type)) and then not From_Limited_With (F_Type) then F_Type := Full_View (F_Type); Set_Etype (Formal, F_Type); end if; if not From_Limited_With (F_Type) then Freeze_And_Append (F_Type, N, Result); end if; 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 artifact of our need to regard -- the end of an instantiation as a freeze point. Otherwise it -- is a definite error. if In_Instance then Set_Is_Frozen (E, False); Result := No_List; return False; elsif not After_Last_Declaration and then not Freezing_Library_Level_Tagged_Type then Error_Msg_Node_1 := F_Type; Error_Msg ("type & must be fully defined before this point", Loc); end if; end if; -- Check suspicious parameter for C function. These tests apply -- only to exported/imported subprograms. if Warn_On_Export_Import and then Comes_From_Source (E) and then (Convention (E) = Convention_C or else Convention (E) = Convention_CPP) and then (Is_Imported (E) or else Is_Exported (E)) and then Convention (E) /= Convention (Formal) and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (F_Type) and then not Has_Warnings_Off (Formal) then -- Qualify mention of formals with subprogram name Error_Msg_Qual_Level := 1; -- Check suspicious use of fat C pointer, but do not emit -- a warning on an access to subprogram when unnesting is -- active. if Is_Access_Type (F_Type) and then Esize (F_Type) > Ttypes.System_Address_Size and then (not Unnest_Subprogram_Mode or else not Is_Access_Subprogram_Type (F_Type)) then Error_Msg_N ("?x?type of & does not correspond to C pointer!", Formal); -- Check suspicious return of boolean elsif Root_Type (F_Type) = Standard_Boolean and then Convention (F_Type) = Convention_Ada and then not Has_Warnings_Off (F_Type) and then not Has_Size_Clause (F_Type) then Error_Msg_N ("& is an 8-bit Ada Boolean?x?", Formal); Error_Msg_N ("\use appropriate corresponding type in C " & "(e.g. char)?x?", Formal); -- Check suspicious tagged type elsif (Is_Tagged_Type (F_Type) or else (Is_Access_Type (F_Type) and then Is_Tagged_Type (Designated_Type (F_Type)))) and then Convention (E) = Convention_C then Error_Msg_N ("?x?& involves a tagged type which does not " & "correspond to any C type!", Formal); -- Check wrong convention subprogram pointer elsif Ekind (F_Type) = E_Access_Subprogram_Type and then not Has_Foreign_Convention (F_Type) then Error_Msg_N ("?x?subprogram pointer & should " & "have foreign convention!", Formal); Error_Msg_Sloc := Sloc (F_Type); Error_Msg_NE ("\?x?add Convention pragma to declaration of &#", Formal, F_Type); end if; -- Turn off name qualification after message output Error_Msg_Qual_Level := 0; end if; -- Check for unconstrained array in exported foreign convention -- case. if Has_Foreign_Convention (E) 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 ("?x?type of argument& is unconstrained array", Warn_Node, Formal); Error_Msg_NE ("?x?foreign caller must pass bounds explicitly", Warn_Node, Formal); Error_Msg_Qual_Level := 0; end if; if not From_Limited_With (F_Type) then if Is_Access_Type (F_Type) then F_Type := Designated_Type (F_Type); end if; -- If the formal is an anonymous_access_to_subprogram -- freeze the subprogram type as well, to prevent -- scope anomalies in gigi, because there is no other -- clear point at which it could be frozen. if Is_Itype (Etype (Formal)) and then Ekind (F_Type) = E_Subprogram_Type then Freeze_And_Append (F_Type, N, Result); end if; end if; Next_Formal (Formal); end loop; -- Case of function: similar checks on return type if Ekind (E) = E_Function then -- Freeze return type R_Type := Etype (E); -- AI05-0151: the return type may have been incomplete at the -- point of declaration. Replace it with the full view, unless the -- current type is a limited view. In that case the full view is -- in a different unit, and gigi finds the non-limited view after -- the other unit is elaborated. if Ekind (R_Type) = E_Incomplete_Type and then Present (Full_View (R_Type)) and then not From_Limited_With (R_Type) then R_Type := Full_View (R_Type); Set_Etype (E, R_Type); end if; Freeze_And_Append (R_Type, N, Result); -- Check suspicious return type for C function if Warn_On_Export_Import and then (Convention (E) = Convention_C or else Convention (E) = Convention_CPP) and then (Is_Imported (E) or else Is_Exported (E)) then -- Check suspicious return of fat C pointer if Is_Access_Type (R_Type) and then Esize (R_Type) > Ttypes.System_Address_Size and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (R_Type) then Error_Msg_N ("?x?return type of& does not correspond to C pointer!", E); -- Check suspicious return of boolean elsif Root_Type (R_Type) = Standard_Boolean and then Convention (R_Type) = Convention_Ada and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (R_Type) and then not Has_Size_Clause (R_Type) then declare N : constant Node_Id := Result_Definition (Declaration_Node (E)); begin Error_Msg_NE ("return type of & is an 8-bit Ada Boolean?x?", N, E); Error_Msg_NE ("\use appropriate corresponding type in C " & "(e.g. char)?x?", N, E); end; -- Check suspicious return tagged type elsif (Is_Tagged_Type (R_Type) or else (Is_Access_Type (R_Type) and then Is_Tagged_Type (Designated_Type (R_Type)))) and then Convention (E) = Convention_C and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (R_Type) then Error_Msg_N ("?x?return type of & does not " & "correspond to C type!", E); -- Check return of wrong convention subprogram pointer elsif Ekind (R_Type) = E_Access_Subprogram_Type and then not Has_Foreign_Convention (R_Type) and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (R_Type) then Error_Msg_N ("?x?& should return a foreign " & "convention subprogram pointer", E); Error_Msg_Sloc := Sloc (R_Type); Error_Msg_NE ("\?x?add Convention pragma to declaration of& #", E, R_Type); end if; end if; -- Give warning for suspicious return of a result of an -- unconstrained array type in a foreign convention function. if Has_Foreign_Convention (E) -- We are looking for a return of unconstrained array and then Is_Array_Type (R_Type) and then not Is_Constrained (R_Type) -- Exclude imported routines, the warning does not belong on -- the import, but rather on the routine definition. and then not Is_Imported (E) -- Check that general warning is enabled, and that it is not -- suppressed for this particular case. and then Warn_On_Export_Import and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (R_Type) then Error_Msg_N ("?x?foreign convention function& should not return " & "unconstrained array!", E); end if; end if; -- Check suspicious use of Import in pure unit (cases where the RM -- allows calls to be omitted). if Is_Imported (E) -- It might be suspicious if the compilation unit has the Pure -- aspect/pragma. and then Has_Pragma_Pure (Cunit_Entity (Current_Sem_Unit)) -- The RM allows omission of calls only in the case of -- library-level subprograms (see RM-10.2.1(18)). and then Is_Library_Level_Entity (E) -- Ignore internally generated entity. This happens in some cases -- of subprograms in specs, where we generate an implied body. and then Comes_From_Source (Import_Pragma (E)) -- Assume run-time knows what it is doing and then not GNAT_Mode -- Assume explicit Pure_Function means import is pure and then not Has_Pragma_Pure_Function (E) -- Don't need warning in relaxed semantics mode and then not Relaxed_RM_Semantics -- Assume convention Intrinsic is OK, since this is specialized. -- This deals with the DEC unit current_exception.ads and then Convention (E) /= Convention_Intrinsic -- Assume that ASM interface knows what it is doing. This deals -- with e.g. unsigned.ads in the AAMP back end. and then Convention (E) /= Convention_Assembler then Error_Msg_N ("pragma Import in Pure unit??", Import_Pragma (E)); Error_Msg_NE ("\calls to & may be omitted (RM 10.2.1(18/3))??", Import_Pragma (E), E); end if; return True; end Freeze_Profile; ------------------------ -- Freeze_Record_Type -- ------------------------ procedure Freeze_Record_Type (Rec : Entity_Id) is ADC : Node_Id; Comp : Entity_Id; IR : Node_Id; Prev : Entity_Id; Junk : Boolean; pragma Warnings (Off, Junk); Aliased_Component : Boolean := False; -- Set True if we find at least one component which is aliased. This -- is used to prevent Implicit_Packing of the record, since packing -- cannot modify the size of alignment of an aliased component. All_Elem_Components : Boolean := True; -- True if all components are of a type whose underlying type is -- elementary. All_Sized_Components : Boolean := True; -- True if all components have a known RM_Size All_Storage_Unit_Components : Boolean := True; -- True if all components have an RM_Size that is a multiple of the -- storage unit. Elem_Component_Total_Esize : Uint := Uint_0; -- Accumulates total Esize values of all elementary components. Used -- for processing of Implicit_Packing. 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, and also -- to detect cases where Implicit_Packing may have an effect). Rec_Pushed : Boolean := False; -- Set True if the record type scope Rec has been pushed on the scope -- stack. Needed for the analysis of delayed aspects specified to the -- components of Rec. Sized_Component_Total_RM_Size : Uint := Uint_0; -- Accumulates total RM_Size values of all sized components. Used -- for processing of Implicit_Packing. Sized_Component_Total_Round_RM_Size : Uint := Uint_0; -- Accumulates total RM_Size values of all sized components, rounded -- individually to a multiple of the storage unit. SSO_ADC : Node_Id; -- Scalar_Storage_Order attribute definition clause for the record SSO_ADC_Component : Boolean := False; -- Set True if we find at least one component whose type has a -- Scalar_Storage_Order attribute definition clause. Unplaced_Component : Boolean := False; -- Set True if we find at least one component with no component -- clause (used to warn about useless Pack pragmas). function Check_Allocator (N : Node_Id) return Node_Id; -- If N is an allocator, possibly wrapped in one or more level of -- qualified expression(s), return the inner allocator node, else -- return Empty. procedure Check_Itype (Typ : 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. Similarly, if the component subtype is a -- regular (not protected) access to subprogram, set the anonymous -- subprogram type to frozen as well, to prevent an out-of-scope -- freeze node at some eventual point of call. Protected operations -- are handled elsewhere. procedure Freeze_Choices_In_Variant_Part (VP : Node_Id); -- Make sure that all types mentioned in Discrete_Choices of the -- variants referenceed by the Variant_Part VP are frozen. This is -- a recursive routine to deal with nested variants. --------------------- -- Check_Allocator -- --------------------- function Check_Allocator (N : Node_Id) return Node_Id is Inner : Node_Id; begin Inner := N; loop if Nkind (Inner) = N_Allocator then return Inner; elsif Nkind (Inner) = N_Qualified_Expression then Inner := Expression (Inner); else return Empty; end if; end loop; end Check_Allocator; ----------------- -- Check_Itype -- ----------------- procedure Check_Itype (Typ : Entity_Id) is Desig : constant Entity_Id := Designated_Type (Typ); 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); Add_To_Result (IR); end if; elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type and then Convention (Desig) /= Convention_Protected then Set_Is_Frozen (Desig); end if; end Check_Itype; ------------------------------------ -- Freeze_Choices_In_Variant_Part -- ------------------------------------ procedure Freeze_Choices_In_Variant_Part (VP : Node_Id) is pragma Assert (Nkind (VP) = N_Variant_Part); Variant : Node_Id; Choice : Node_Id; CL : Node_Id; begin -- Loop through variants Variant := First_Non_Pragma (Variants (VP)); while Present (Variant) loop -- Loop through choices, checking that all types are frozen Choice := First_Non_Pragma (Discrete_Choices (Variant)); while Present (Choice) loop if Nkind (Choice) in N_Has_Etype and then Present (Etype (Choice)) then Freeze_And_Append (Etype (Choice), N, Result); end if; Next_Non_Pragma (Choice); end loop; -- Check for nested variant part to process CL := Component_List (Variant); if not Null_Present (CL) then if Present (Variant_Part (CL)) then Freeze_Choices_In_Variant_Part (Variant_Part (CL)); end if; end if; Next_Non_Pragma (Variant); end loop; end Freeze_Choices_In_Variant_Part; -- Start of processing for Freeze_Record_Type begin -- Deal with delayed aspect specifications for components. The -- analysis of the aspect is required to be delayed to the freeze -- point, thus we analyze the pragma or attribute definition -- clause in the tree at this point. We also analyze the aspect -- specification node at the freeze point when the aspect doesn't -- correspond to pragma/attribute definition clause. Comp := First_Entity (Rec); while Present (Comp) loop if Ekind (Comp) = E_Component and then Has_Delayed_Aspects (Comp) then if not Rec_Pushed then Push_Scope (Rec); Rec_Pushed := True; -- The visibility to the discriminants must be restored in -- order to properly analyze the aspects. if Has_Discriminants (Rec) then Install_Discriminants (Rec); end if; end if; Analyze_Aspects_At_Freeze_Point (Comp); end if; Next_Entity (Comp); end loop; -- Pop the scope if Rec scope has been pushed on the scope stack -- during the delayed aspect analysis process. if Rec_Pushed then if Has_Discriminants (Rec) then Uninstall_Discriminants (Rec); end if; Pop_Scope; end if; -- Freeze components and embedded subtypes Comp := First_Entity (Rec); Prev := Empty; while Present (Comp) loop if Is_Aliased (Comp) then Aliased_Component := True; end if; -- Handle the component and discriminant case if Ekind_In (Comp, E_Component, 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), N, Result); -- Warn for pragma Pack overriding foreign convention if Has_Foreign_Convention (Etype (Comp)) and then Has_Pragma_Pack (Rec) -- Don't warn for aliased components, since override -- cannot happen in that case. and then not Is_Aliased (Comp) then declare CN : constant Name_Id := Get_Convention_Name (Convention (Etype (Comp))); PP : constant Node_Id := Get_Pragma (Rec, Pragma_Pack); begin if Present (PP) then Error_Msg_Name_1 := CN; Error_Msg_Sloc := Sloc (Comp); Error_Msg_N ("pragma Pack affects convention % component#??", PP); Error_Msg_Name_1 := CN; Error_Msg_NE ("\component & may not have % compatible " & "representation??", PP, Comp); end if; end; end if; -- 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. if Present (CC) then Placed_Component := True; -- We omit this test in a generic context, it will be -- applied at instantiation time. if Inside_A_Generic then null; -- Also omit this test in CodePeer mode, since we do not -- have sufficient info on size and rep clauses. elsif CodePeer_Mode then null; -- Omit check if component has a generic type. This can -- happen in an instantiation within a generic in ASIS -- mode, where we force freeze actions without full -- expansion. elsif Is_Generic_Type (Etype (Comp)) then null; -- Do the check 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; end; end if; -- Gather data for possible Implicit_Packing later. Note that at -- this stage we might be dealing with a real component, or with -- an implicit subtype declaration. if Known_Static_RM_Size (Etype (Comp)) then declare Comp_Type : constant Entity_Id := Etype (Comp); Comp_Size : constant Uint := RM_Size (Comp_Type); SSU : constant Int := Ttypes.System_Storage_Unit; begin Sized_Component_Total_RM_Size := Sized_Component_Total_RM_Size + Comp_Size; Sized_Component_Total_Round_RM_Size := Sized_Component_Total_Round_RM_Size + (Comp_Size + SSU - 1) / SSU * SSU; if Present (Underlying_Type (Comp_Type)) and then Is_Elementary_Type (Underlying_Type (Comp_Type)) then Elem_Component_Total_Esize := Elem_Component_Total_Esize + Esize (Comp_Type); else All_Elem_Components := False; if Comp_Size mod SSU /= 0 then All_Storage_Unit_Components := False; end if; end if; end; else All_Sized_Components := False; 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; begin -- We have a difficult case to handle here. Suppose Rec is -- 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. S := Scope (Rec); 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 Link_Entities (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))) then declare Alloc : constant Node_Id := Check_Allocator (Expression (Parent (Comp))); begin if Present (Alloc) then -- If component is pointer to a class-wide 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)), N, Result); elsif Nkind (Expression (Alloc)) = N_Subtype_Indication then Freeze_And_Append (Entity (Subtype_Mark (Expression (Alloc))), N, Result); end if; elsif Is_Itype (Designated_Type (Etype (Comp))) then Check_Itype (Etype (Comp)); else Freeze_And_Append (Designated_Type (Etype (Comp)), N, Result); end if; end if; end; elsif Is_Access_Type (Etype (Comp)) and then Is_Itype (Designated_Type (Etype (Comp))) then Check_Itype (Etype (Comp)); -- Freeze the designated type when initializing a component with -- an aggregate in case the aggregate contains allocators. -- type T is ...; -- type T_Ptr is access all T; -- type T_Array is array ... of T_Ptr; -- type Rec is record -- Comp : T_Array := (others => ...); -- end record; elsif Is_Array_Type (Etype (Comp)) and then Is_Access_Type (Component_Type (Etype (Comp))) then declare Comp_Par : constant Node_Id := Parent (Comp); Desig_Typ : constant Entity_Id := Designated_Type (Component_Type (Etype (Comp))); begin -- The only case when this sort of freezing is not done is -- when the designated type is class-wide and the root type -- is the record owning the component. This scenario results -- in a circularity because the class-wide type requires -- primitives that have not been created yet as the root -- type is in the process of being frozen. -- type Rec is tagged; -- type Rec_Ptr is access all Rec'Class; -- type Rec_Array is array ... of Rec_Ptr; -- type Rec is record -- Comp : Rec_Array := (others => ...); -- end record; if Is_Class_Wide_Type (Desig_Typ) and then Root_Type (Desig_Typ) = Rec then null; elsif Is_Fully_Defined (Desig_Typ) and then Present (Comp_Par) and then Nkind (Comp_Par) = N_Component_Declaration and then Present (Expression (Comp_Par)) and then Nkind (Expression (Comp_Par)) = N_Aggregate then Freeze_And_Append (Desig_Typ, N, Result); end if; end; end if; Prev := Comp; Next_Entity (Comp); end loop; SSO_ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Scalar_Storage_Order); -- If the record type has Complex_Representation, then it is treated -- as a scalar in the back end so the storage order is irrelevant. if Has_Complex_Representation (Rec) then if Present (SSO_ADC) then Error_Msg_N ("??storage order has no effect with Complex_Representation", SSO_ADC); end if; else -- Deal with default setting of reverse storage order Set_SSO_From_Default (Rec); -- Check consistent attribute setting on component types declare Comp_ADC_Present : Boolean; begin Comp := First_Component (Rec); while Present (Comp) loop Check_Component_Storage_Order (Encl_Type => Rec, Comp => Comp, ADC => SSO_ADC, Comp_ADC_Present => Comp_ADC_Present); SSO_ADC_Component := SSO_ADC_Component or Comp_ADC_Present; Next_Component (Comp); end loop; end; -- Now deal with reverse storage order/bit order issues if Present (SSO_ADC) then -- Check compatibility of Scalar_Storage_Order with Bit_Order, -- if the former is specified. if Reverse_Bit_Order (Rec) /= Reverse_Storage_Order (Rec) then -- Note: report error on Rec, not on SSO_ADC, as ADC may -- apply to some ancestor type. Error_Msg_Sloc := Sloc (SSO_ADC); Error_Msg_N ("scalar storage order for& specified# inconsistent with " & "bit order", Rec); end if; -- Warn if there is a Scalar_Storage_Order attribute definition -- clause but no component clause, no component that itself has -- such an attribute definition, and no pragma Pack. if not (Placed_Component or else SSO_ADC_Component or else Is_Packed (Rec)) then Error_Msg_N ("??scalar storage order specified but no component " & "clause", SSO_ADC); end if; end if; end if; -- Deal with Bit_Order aspect ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order); if Present (ADC) and then Base_Type (Rec) = Rec then if not (Placed_Component or else Present (SSO_ADC) or else Is_Packed (Rec)) then -- Warn if clause has no effect when no component clause is -- present, but suppress warning if the Bit_Order is required -- due to the presence of a Scalar_Storage_Order attribute. Error_Msg_N ("??bit order specification has no effect", ADC); Error_Msg_N ("\??since no component clauses were specified", ADC); -- Here is where we do the processing to adjust component clauses -- for reversed bit order, when not using reverse SSO. If an error -- has been reported on Rec already (such as SSO incompatible with -- bit order), don't bother adjusting as this may generate extra -- noise. elsif Reverse_Bit_Order (Rec) and then not Reverse_Storage_Order (Rec) and then not Error_Posted (Rec) then Adjust_Record_For_Reverse_Bit_Order (Rec); -- Case where we have both an explicit Bit_Order and the same -- Scalar_Storage_Order: leave record untouched, the back-end -- will take care of required layout conversions. else null; end if; end if; -- Complete error checking on record representation clause (e.g. -- overlap of components). This is called after adjusting the -- record for reverse bit order. declare RRC : constant Node_Id := Get_Record_Representation_Clause (Rec); begin if Present (RRC) then Check_Record_Representation_Clause (RRC); end if; end; -- 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. We do not give -- this warning if Optimize_Alignment is set to Space, since the -- pragma Pack does have an effect in this case (it always resets -- the alignment to one). if Ekind (Rec) = E_Record_Type and then Is_Packed (Rec) and then not Unplaced_Component and then Optimize_Alignment /= 'S' 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 -- CODEFIX ("??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. if Ekind (Rec) = E_Record_Type then if Present (Corresponding_Remote_Type (Rec)) then Freeze_And_Append (Corresponding_Remote_Type (Rec), N, Result); end if; -- Check for controlled components, unchecked unions, and type -- invariants. Comp := First_Component (Rec); while Present (Comp) loop -- Do not set Has_Controlled_Component on a class-wide -- equivalent type. See Make_CW_Equivalent_Type. if not Is_Class_Wide_Equivalent_Type (Rec) and then (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); end if; if Has_Unchecked_Union (Etype (Comp)) then Set_Has_Unchecked_Union (Rec); end if; -- The record type requires its own invariant procedure in -- order to verify the invariant of each individual component. -- Do not consider internal components such as _parent because -- parent class-wide invariants are always inherited. -- In GNATprove mode, the component invariants are checked by -- other means. They should not be added to the record type -- invariant procedure, so that the procedure can be used to -- check the recordy type invariants if any. if Comes_From_Source (Comp) and then Has_Invariants (Etype (Comp)) and then not GNATprove_Mode then Set_Has_Own_Invariants (Rec); end if; -- Scan component declaration for likely misuses of current -- instance, either in a constraint or a default expression. if Has_Per_Object_Constraint (Comp) then Check_Current_Instance (Parent (Comp)); end if; Next_Component (Comp); end loop; end if; -- Enforce the restriction that access attributes with a current -- instance prefix can only apply to limited types. This comment -- is floating here, but does not seem to belong here??? -- Set component alignment if not otherwise already set 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; -- See if Size is too small as is (and implicit packing might help) if not Is_Packed (Rec) -- No implicit packing if even one component is explicitly placed and then not Placed_Component -- Or even one component is aliased and then not Aliased_Component -- Must have size clause and all sized components and then Has_Size_Clause (Rec) and then All_Sized_Components -- Do not try implicit packing on records with discriminants, too -- complicated, especially in the variant record case. and then not Has_Discriminants (Rec) -- We want to implicitly pack if the specified size of the record -- is less than the sum of the object sizes (no point in packing -- if this is not the case), if we can compute it, i.e. if we have -- only elementary components. Otherwise, we have at least one -- composite component and we want to implicitly pack only if bit -- packing is required for it, as we are sure in this case that -- the back end cannot do the expected layout without packing. and then ((All_Elem_Components and then RM_Size (Rec) < Elem_Component_Total_Esize) or else (not All_Elem_Components and then not All_Storage_Unit_Components and then RM_Size (Rec) < Sized_Component_Total_Round_RM_Size)) -- And the total RM size cannot be greater than the specified size -- since otherwise packing will not get us where we have to be. and then Sized_Component_Total_RM_Size <= RM_Size (Rec) -- Never do implicit packing in CodePeer or SPARK modes since -- we don't do any packing in these modes, since this generates -- over-complex code that confuses static analysis, and in -- general, neither CodePeer not GNATprove care about the -- internal representation of objects. and then not (CodePeer_Mode or GNATprove_Mode) then -- If implicit packing enabled, do it if Implicit_Packing then Set_Is_Packed (Rec); -- Otherwise flag the size clause else declare Sz : constant Node_Id := Size_Clause (Rec); begin Error_Msg_NE -- CODEFIX ("size given for& too small", Sz, Rec); Error_Msg_N -- CODEFIX ("\use explicit pragma Pack " & "or use pragma Implicit_Packing", Sz); end; end if; end if; -- The following checks are relevant only when SPARK_Mode is on as -- they are not standard Ada legality rules. if SPARK_Mode = On then -- A discriminated type cannot be effectively volatile -- (SPARK RM 7.1.3(5)). if Is_Effectively_Volatile (Rec) then if Has_Discriminants (Rec) then Error_Msg_N ("discriminated type & cannot be volatile", Rec); end if; -- A non-effectively volatile record type cannot contain -- effectively volatile components (SPARK RM 7.1.3(6)). else Comp := First_Component (Rec); while Present (Comp) loop if Comes_From_Source (Comp) and then Is_Effectively_Volatile (Etype (Comp)) then Error_Msg_Name_1 := Chars (Rec); Error_Msg_N ("component & of non-volatile type % cannot be " & "volatile", Comp); end if; Next_Component (Comp); end loop; end if; -- A type which does not yield a synchronized object cannot have -- a component that yields a synchronized object (SPARK RM 9.5). if not Yields_Synchronized_Object (Rec) then Comp := First_Component (Rec); while Present (Comp) loop if Comes_From_Source (Comp) and then Yields_Synchronized_Object (Etype (Comp)) then Error_Msg_Name_1 := Chars (Rec); Error_Msg_N ("component & of non-synchronized type % cannot be " & "synchronized", Comp); end if; Next_Component (Comp); end loop; end if; -- A Ghost type cannot have a component of protected or task type -- (SPARK RM 6.9(19)). if Is_Ghost_Entity (Rec) then Comp := First_Component (Rec); while Present (Comp) loop if Comes_From_Source (Comp) and then Is_Concurrent_Type (Etype (Comp)) then Error_Msg_Name_1 := Chars (Rec); Error_Msg_N ("component & of ghost type % cannot be concurrent", Comp); end if; Next_Component (Comp); end loop; end if; end if; -- Make sure that if we have an iterator aspect, then we have -- either Constant_Indexing or Variable_Indexing. declare Iterator_Aspect : Node_Id; begin Iterator_Aspect := Find_Aspect (Rec, Aspect_Iterator_Element); if No (Iterator_Aspect) then Iterator_Aspect := Find_Aspect (Rec, Aspect_Default_Iterator); end if; if Present (Iterator_Aspect) then if Has_Aspect (Rec, Aspect_Constant_Indexing) or else Has_Aspect (Rec, Aspect_Variable_Indexing) then null; else Error_Msg_N ("Iterator_Element requires indexing aspect", Iterator_Aspect); end if; end if; end; -- All done if not a full record definition if Ekind (Rec) /= E_Record_Type then return; end if; -- Finally we need to check the variant part to make sure that -- all types within choices are properly frozen as part of the -- freezing of the record type. Check_Variant_Part : declare D : constant Node_Id := Declaration_Node (Rec); T : Node_Id; C : Node_Id; begin -- Find component list C := Empty; if Nkind (D) = N_Full_Type_Declaration then T := Type_Definition (D); if Nkind (T) = N_Record_Definition then C := Component_List (T); elsif Nkind (T) = N_Derived_Type_Definition and then Present (Record_Extension_Part (T)) then C := Component_List (Record_Extension_Part (T)); end if; end if; -- Case of variant part present if Present (C) and then Present (Variant_Part (C)) then Freeze_Choices_In_Variant_Part (Variant_Part (C)); end if; -- Note: we used to call Check_Choices here, but it is too early, -- since predicated subtypes are frozen here, but their freezing -- actions are in Analyze_Freeze_Entity, which has not been called -- yet for entities frozen within this procedure, so we moved that -- call to the Analyze_Freeze_Entity for the record type. end Check_Variant_Part; -- Check that all the primitives of an interface type are abstract -- or null procedures. if Is_Interface (Rec) and then not Error_Posted (Parent (Rec)) then declare Elmt : Elmt_Id; Subp : Entity_Id; begin Elmt := First_Elmt (Primitive_Operations (Rec)); while Present (Elmt) loop Subp := Node (Elmt); if not Is_Abstract_Subprogram (Subp) -- Avoid reporting the error on inherited primitives and then Comes_From_Source (Subp) then Error_Msg_Name_1 := Chars (Subp); if Ekind (Subp) = E_Procedure then if not Null_Present (Parent (Subp)) then Error_Msg_N ("interface procedure % must be abstract or null", Parent (Subp)); end if; else Error_Msg_N ("interface function % must be abstract", Parent (Subp)); end if; end if; Next_Elmt (Elmt); end loop; end; end if; -- For a derived tagged type, check whether inherited primitives -- might require a wrapper to handle class-wide conditions. if Is_Tagged_Type (Rec) and then Is_Derived_Type (Rec) then Check_Inherited_Conditions (Rec); end if; end Freeze_Record_Type; ------------------------------- -- Has_Boolean_Aspect_Import -- ------------------------------- function Has_Boolean_Aspect_Import (E : Entity_Id) return Boolean is Decl : constant Node_Id := Declaration_Node (E); Asp : Node_Id; Expr : Node_Id; begin if Has_Aspects (Decl) then Asp := First (Aspect_Specifications (Decl)); while Present (Asp) loop Expr := Expression (Asp); -- The value of aspect Import is True when the expression is -- either missing or it is explicitly set to True. if Get_Aspect_Id (Asp) = Aspect_Import and then (No (Expr) or else (Compile_Time_Known_Value (Expr) and then Is_True (Expr_Value (Expr)))) then return True; end if; Next (Asp); end loop; end if; return False; end Has_Boolean_Aspect_Import; ------------------------- -- Inherit_Freeze_Node -- ------------------------- procedure Inherit_Freeze_Node (Fnod : Node_Id; Typ : Entity_Id) is Typ_Fnod : constant Node_Id := Freeze_Node (Typ); begin Set_Freeze_Node (Typ, Fnod); Set_Entity (Fnod, Typ); -- The input type had an existing node. Propagate relevant attributes -- from the old freeze node to the inherited freeze node. -- ??? if both freeze nodes have attributes, would they differ? if Present (Typ_Fnod) then -- Attribute Access_Types_To_Process if Present (Access_Types_To_Process (Typ_Fnod)) and then No (Access_Types_To_Process (Fnod)) then Set_Access_Types_To_Process (Fnod, Access_Types_To_Process (Typ_Fnod)); end if; -- Attribute Actions if Present (Actions (Typ_Fnod)) and then No (Actions (Fnod)) then Set_Actions (Fnod, Actions (Typ_Fnod)); end if; -- Attribute First_Subtype_Link if Present (First_Subtype_Link (Typ_Fnod)) and then No (First_Subtype_Link (Fnod)) then Set_First_Subtype_Link (Fnod, First_Subtype_Link (Typ_Fnod)); end if; -- Attribute TSS_Elist if Present (TSS_Elist (Typ_Fnod)) and then No (TSS_Elist (Fnod)) then Set_TSS_Elist (Fnod, TSS_Elist (Typ_Fnod)); end if; end if; end Inherit_Freeze_Node; ------------------------------ -- Wrap_Imported_Subprogram -- ------------------------------ -- The issue here is that our normal approach of checking preconditions -- and postconditions does not work for imported procedures, since we -- are not generating code for the body. To get around this we create -- a wrapper, as shown by the following example: -- procedure K (A : Integer); -- pragma Import (C, K); -- The spec is rewritten by removing the effects of pragma Import, but -- leaving the convention unchanged, as though the source had said: -- procedure K (A : Integer); -- pragma Convention (C, K); -- and we create a body, added to the entity K freeze actions, which -- looks like: -- procedure K (A : Integer) is -- procedure K (A : Integer); -- pragma Import (C, K); -- begin -- K (A); -- end K; -- Now the contract applies in the normal way to the outer procedure, -- and the inner procedure has no contracts, so there is no problem -- in just calling it to get the original effect. -- In the case of a function, we create an appropriate return statement -- for the subprogram body that calls the inner procedure. procedure Wrap_Imported_Subprogram (E : Entity_Id) is function Copy_Import_Pragma return Node_Id; -- Obtain a copy of the Import_Pragma which belongs to subprogram E ------------------------ -- Copy_Import_Pragma -- ------------------------ function Copy_Import_Pragma return Node_Id is -- The subprogram should have an import pragma, otherwise it does -- need a wrapper. Prag : constant Node_Id := Import_Pragma (E); pragma Assert (Present (Prag)); -- Save all semantic fields of the pragma Save_Asp : constant Node_Id := Corresponding_Aspect (Prag); Save_From : constant Boolean := From_Aspect_Specification (Prag); Save_Prag : constant Node_Id := Next_Pragma (Prag); Save_Rep : constant Node_Id := Next_Rep_Item (Prag); Result : Node_Id; begin -- Reset all semantic fields. This avoids a potential infinite -- loop when the pragma comes from an aspect as the duplication -- will copy the aspect, then copy the corresponding pragma and -- so on. Set_Corresponding_Aspect (Prag, Empty); Set_From_Aspect_Specification (Prag, False); Set_Next_Pragma (Prag, Empty); Set_Next_Rep_Item (Prag, Empty); Result := Copy_Separate_Tree (Prag); -- Restore the original semantic fields Set_Corresponding_Aspect (Prag, Save_Asp); Set_From_Aspect_Specification (Prag, Save_From); Set_Next_Pragma (Prag, Save_Prag); Set_Next_Rep_Item (Prag, Save_Rep); return Result; end Copy_Import_Pragma; -- Local variables Loc : constant Source_Ptr := Sloc (E); CE : constant Name_Id := Chars (E); Bod : Node_Id; Forml : Entity_Id; Parms : List_Id; Prag : Node_Id; Spec : Node_Id; Stmt : Node_Id; -- Start of processing for Wrap_Imported_Subprogram begin -- Nothing to do if not imported if not Is_Imported (E) then return; -- Test enabling conditions for wrapping elsif Is_Subprogram (E) and then Present (Contract (E)) and then Present (Pre_Post_Conditions (Contract (E))) and then not GNATprove_Mode then -- Here we do the wrap -- Note on calls to Copy_Separate_Tree. The trees we are copying -- here are fully analyzed, but we definitely want fully syntactic -- unanalyzed trees in the body we construct, so that the analysis -- generates the right visibility, and that is exactly what the -- calls to Copy_Separate_Tree give us. Prag := Copy_Import_Pragma; -- Fix up spec so it is no longer imported and has convention Ada Set_Has_Completion (E, False); Set_Import_Pragma (E, Empty); Set_Interface_Name (E, Empty); Set_Is_Imported (E, False); Set_Convention (E, Convention_Ada); -- Grab the subprogram declaration and specification Spec := Declaration_Node (E); -- Build parameter list that we need Parms := New_List; Forml := First_Formal (E); while Present (Forml) loop Append_To (Parms, Make_Identifier (Loc, Chars (Forml))); Next_Formal (Forml); end loop; -- Build the call -- An imported function whose result type is anonymous access -- creates a new anonymous access type when it is relocated into -- the declarations of the body generated below. As a result, the -- accessibility level of these two anonymous access types may not -- be compatible even though they are essentially the same type. -- Use an unchecked type conversion to reconcile this case. Note -- that the conversion is safe because in the named access type -- case, both the body and imported function utilize the same -- type. if Ekind_In (E, E_Function, E_Generic_Function) then Stmt := Make_Simple_Return_Statement (Loc, Expression => Unchecked_Convert_To (Etype (E), Make_Function_Call (Loc, Name => Make_Identifier (Loc, CE), Parameter_Associations => Parms))); else Stmt := Make_Procedure_Call_Statement (Loc, Name => Make_Identifier (Loc, CE), Parameter_Associations => Parms); end if; -- Now build the body Bod := Make_Subprogram_Body (Loc, Specification => Copy_Separate_Tree (Spec), Declarations => New_List ( Make_Subprogram_Declaration (Loc, Specification => Copy_Separate_Tree (Spec)), Prag), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List (Stmt), End_Label => Make_Identifier (Loc, CE))); -- Append the body to freeze result Add_To_Result (Bod); return; -- Case of imported subprogram that does not get wrapped else -- Set Is_Public. All imported entities need an external symbol -- created for them since they are always referenced from another -- object file. Note this used to be set when we set Is_Imported -- back in Sem_Prag, but now we delay it to this point, since we -- don't want to set this flag if we wrap an imported subprogram. Set_Is_Public (E); end if; end Wrap_Imported_Subprogram; -- Start of processing for Freeze_Entity begin -- The entity being frozen may be subject to pragma Ghost. Set the mode -- now to ensure that any nodes generated during freezing are properly -- flagged as Ghost. Set_Ghost_Mode (E); -- 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 Result := No_List; goto Leave; -- Do not freeze if we are preanalyzing without freezing elsif Inside_Preanalysis_Without_Freezing > 0 then Result := No_List; goto Leave; elsif Ekind (E) = E_Generic_Package then Result := Freeze_Generic_Entities (E); goto Leave; -- 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. -- However, aspects must be analyzed because they may be queried later -- within the generic itself, and the corresponding pragma or attribute -- definition has not been analyzed yet. After this, indicate that the -- entity has no further delayed aspects, to prevent a later aspect -- analysis out of the scope of the generic. elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then if Has_Delayed_Aspects (E) then Analyze_Aspects_At_Freeze_Point (E); Set_Has_Delayed_Aspects (E, False); end if; Result := No_List; goto Leave; -- AI05-0213: A formal incomplete type does not freeze the actual. In -- the instance, the same applies to the subtype renaming the actual. elsif Is_Private_Type (E) and then Is_Generic_Actual_Type (E) and then No (Full_View (Base_Type (E))) and then Ada_Version >= Ada_2012 then Result := No_List; goto Leave; -- Formal subprograms are never frozen elsif Is_Formal_Subprogram (E) then Result := No_List; goto Leave; -- Generic types are never frozen as they lack delayed semantic checks elsif Is_Generic_Type (E) then Result := No_List; goto Leave; -- 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 (e.g. in the case of a deferred constant being used -- in a default expression). 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 freeze the entity. A subprogram that -- is a child unit body that acts as a spec does not have a spec that -- comes from source, but can only come from source. 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; begin S := Current_Scope; while Present (S) loop if Is_Overloadable (S) then if Comes_From_Source (S) or else Is_Generic_Instance (S) or else Is_Child_Unit (S) then exit; else Result := No_List; goto Leave; 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 in 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; begin S := Scope (Test_E); while Present (S) loop if Is_Generic_Instance (S) then exit; else S := Scope (S); end if; end loop; if No (S) then Result := No_List; goto Leave; end if; end; end if; -- Add checks to detect proper initialization of scalars that may appear -- as subprogram parameters. if Is_Subprogram (E) and then Check_Validity_Of_Parameters then Apply_Parameter_Validity_Checks (E); end if; -- Deal with delayed aspect specifications. The analysis of the aspect -- is required to be delayed to the freeze point, thus we analyze the -- pragma or attribute definition clause in the tree at this point. We -- also analyze the aspect specification node at the freeze point when -- the aspect doesn't correspond to pragma/attribute definition clause. -- In addition, a derived type may have inherited aspects that were -- delayed in the parent, so these must also be captured now. if Has_Delayed_Aspects (E) or else May_Inherit_Delayed_Rep_Aspects (E) then Analyze_Aspects_At_Freeze_Point (E); end if; -- Here to freeze the entity 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. For the case on intrinsics, if no -- external name is specified, then calls will be handled in -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an -- external name is provided, then Expand_Intrinsic_Call leaves -- calls in place for expansion by GIGI. if (Is_Imported (E) or else Is_Exported (E)) and then No (Interface_Name (E)) and then Convention (E) /= Convention_Stubbed and then Convention (E) /= Convention_Intrinsic then Set_Encoded_Interface_Name (E, Get_Default_External_Name (E)); -- If entity is an atomic object appearing in a declaration and -- the expression is an aggregate, assign it 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). elsif Is_Atomic_Or_VFA (E) and then Nkind (Parent (E)) = N_Object_Declaration and then Present (Expression (Parent (E))) and then Nkind (Expression (Parent (E))) = N_Aggregate and then Is_Atomic_VFA_Aggregate (Expression (Parent (E))) then null; end if; -- Subprogram case if Is_Subprogram (E) then -- Check for needing to wrap imported subprogram Wrap_Imported_Subprogram (E); -- Freeze all parameter types and the return type (RM 13.14(14)). -- However skip this for internal subprograms. This is also where -- any extra formal parameters are created since we now know -- whether the subprogram will use a foreign convention. -- In Ada 2012, freezing a subprogram does not always freeze the -- corresponding profile (see AI05-019). An attribute reference -- is not a freezing point of the profile. Flag Do_Freeze_Profile -- indicates whether the profile should be frozen now. -- Other constructs that should not freeze ??? -- This processing doesn't apply to internal entities (see below) if not Is_Internal (E) and then Do_Freeze_Profile then if not Freeze_Profile (E) then goto Leave; end if; end if; -- Must freeze its parent first if it is a derived subprogram if Present (Alias (E)) then Freeze_And_Append (Alias (E), N, Result); end if; -- We don't freeze internal subprograms, because we don't normally -- want addition of extra formals or mechanism setting to happen -- for those. However we do pass through predefined dispatching -- cases, since extra formals may be needed in some cases, such as -- for the stream 'Input function (build-in-place formals). if not Is_Internal (E) or else Is_Predefined_Dispatching_Operation (E) then Freeze_Subprogram (E); end if; -- If warning on suspicious contracts then check for the case of -- a postcondition other than False for a No_Return subprogram. if No_Return (E) and then Warn_On_Suspicious_Contract and then Present (Contract (E)) then declare Prag : Node_Id := Pre_Post_Conditions (Contract (E)); Exp : Node_Id; begin while Present (Prag) loop if Nam_In (Pragma_Name_Unmapped (Prag), Name_Post, Name_Postcondition, Name_Refined_Post) then Exp := Expression (First (Pragma_Argument_Associations (Prag))); if Nkind (Exp) /= N_Identifier or else Chars (Exp) /= Name_False then Error_Msg_NE ("useless postcondition, & is marked " & "No_Return?T?", Exp, E); end if; end if; Prag := Next_Pragma (Prag); end loop; end; 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), N, Result); -- For an object of an anonymous array type, aspects on the -- object declaration apply to the type itself. This is the -- case for Atomic_Components, Volatile_Components, and -- Independent_Components. In these cases analysis of the -- generated pragma will mark the anonymous types accordingly, -- and the object itself does not require a freeze node. if Ekind (E) = E_Variable and then Is_Itype (Etype (E)) and then Is_Array_Type (Etype (E)) and then Has_Delayed_Aspects (E) then Set_Has_Delayed_Aspects (E, False); Set_Has_Delayed_Freeze (E, False); Set_Freeze_Node (E, Empty); end if; end if; -- Special processing for objects created by object declaration if Nkind (Declaration_Node (E)) = N_Object_Declaration then Freeze_Object_Declaration (E); 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) and then not Has_Boolean_Aspect_Import (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 (RM 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 (RM 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_In (E, E_Variable, E_Constant, E_Loop_Parameter) or else Is_Formal (E) then Layout_Object (E); end if; -- For an object that does not have delayed freezing, and whose -- initialization actions have been captured in a compound -- statement, move them back now directly within the enclosing -- statement sequence. if Ekind_In (E, E_Constant, E_Variable) and then not Has_Delayed_Freeze (E) then Explode_Initialization_Compound_Statement (E); end if; -- Do not generate a freeze node for a generic unit if Is_Generic_Unit (E) then Result := No_List; goto Leave; end if; end if; -- Case of a type or subtype being frozen else -- Verify several SPARK legality rules related to Ghost types now -- that the type is frozen. Check_Ghost_Type (E); -- We used to check here that a full type must have preelaborable -- initialization if it completes a private type specified with -- pragma Preelaborable_Initialization, but that missed cases where -- the types occur within a generic package, since the freezing -- that occurs within a containing scope generally skips traversal -- of a generic unit's declarations (those will be frozen within -- instances). This check was moved to Analyze_Package_Specification. -- 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. -- In Ada 2012, Freeze_Entities is also used in the front end to -- trigger the analysis of aspect expressions, so in this case we -- want to continue the freezing process. -- Is_Generic_Unit (Scope (E)) is dubious here, do we want instead -- In_Generic_Scope (E)??? if Present (Scope (E)) and then Is_Generic_Unit (Scope (E)) and then (not Has_Predicates (E) and then not Has_Delayed_Freeze (E)) then Check_Compile_Time_Size (E); Result := No_List; goto Leave; end if; -- Check for error of Type_Invariant'Class applied to an untagged -- type (check delayed to freeze time when full type is available). declare Prag : constant Node_Id := Get_Pragma (E, Pragma_Invariant); begin if Present (Prag) and then Class_Present (Prag) and then not Is_Tagged_Type (E) then Error_Msg_NE ("Type_Invariant''Class cannot be specified for &", Prag, E); Error_Msg_N ("\can only be specified for a tagged type", Prag); end if; end; -- Deal with special cases of freezing for subtype if E /= Base_Type (E) then -- Before we do anything else, a specific test for the case of a -- size given for an array where the array would need to be packed -- in order for the size to be honored, but is not. This is the -- case where implicit packing may apply. The reason we do this so -- early is that, if we have implicit packing, the layout of the -- base type is affected, so we must do this before we freeze the -- base type. -- We could do this processing only if implicit packing is enabled -- since in all other cases, the error would be caught by the back -- end. However, we choose to do the check even if we do not have -- implicit packing enabled, since this allows us to give a more -- useful error message (advising use of pragma Implicit_Packing -- or pragma Pack). if Is_Array_Type (E) then declare Ctyp : constant Entity_Id := Component_Type (E); Rsiz : constant Uint := RM_Size (Ctyp); SZ : constant Node_Id := Size_Clause (E); Btyp : constant Entity_Id := Base_Type (E); Lo : Node_Id; Hi : Node_Id; Indx : Node_Id; Dim : Uint; Num_Elmts : Uint := Uint_1; -- Number of elements in array begin -- Check enabling conditions. These are straightforward -- except for the test for a limited composite type. This -- eliminates the rare case of a array of limited components -- where there are issues of whether or not we can go ahead -- and pack the array (since we can't freely pack and unpack -- arrays if they are limited). -- Note that we check the root type explicitly because the -- whole point is we are doing this test before we have had -- a chance to freeze the base type (and it is that freeze -- action that causes stuff to be inherited). -- The conditions on the size are identical to those used in -- Freeze_Array_Type to set the Is_Packed flag. if Has_Size_Clause (E) and then Known_Static_RM_Size (E) and then not Is_Packed (E) and then not Has_Pragma_Pack (E) and then not Has_Component_Size_Clause (E) and then Known_Static_RM_Size (Ctyp) and then Rsiz <= 64 and then not (Addressable (Rsiz) and then Known_Static_Esize (Ctyp) and then Esize (Ctyp) = Rsiz) and then not (Rsiz mod System_Storage_Unit = 0 and then Is_Composite_Type (Ctyp)) and then not Is_Limited_Composite (E) and then not Is_Packed (Root_Type (E)) and then not Has_Component_Size_Clause (Root_Type (E)) and then not (CodePeer_Mode or GNATprove_Mode) then -- Compute number of elements in array Indx := First_Index (E); while Present (Indx) loop Get_Index_Bounds (Indx, Lo, Hi); if not (Compile_Time_Known_Value (Lo) and then Compile_Time_Known_Value (Hi)) then goto No_Implicit_Packing; end if; Dim := Expr_Value (Hi) - Expr_Value (Lo) + 1; if Dim >= 0 then Num_Elmts := Num_Elmts * Dim; else Num_Elmts := Uint_0; end if; Next_Index (Indx); end loop; -- What we are looking for here is the situation where -- the RM_Size given would be exactly right if there was -- a pragma Pack, resulting in the component size being -- the RM_Size of the component type. if RM_Size (E) = Num_Elmts * Rsiz then -- For implicit packing mode, just set the component -- size and Freeze_Array_Type will do the rest. if Implicit_Packing then Set_Component_Size (Btyp, Rsiz); -- Otherwise give an error message else Error_Msg_NE ("size given for& too small", SZ, E); Error_Msg_N -- CODEFIX ("\use explicit pragma Pack or use pragma " & "Implicit_Packing", SZ); end if; end if; end if; end; end if; <<No_Implicit_Packing>> -- If ancestor subtype present, freeze that first. Note that this -- will also get the base type frozen. Need RM reference ??? Atype := Ancestor_Subtype (E); if Present (Atype) then Freeze_And_Append (Atype, N, Result); -- No ancestor subtype present else -- See if we have a nearest ancestor that has a predicate. -- That catches the case of derived type with a predicate. -- Need RM reference here ??? Atype := Nearest_Ancestor (E); if Present (Atype) and then Has_Predicates (Atype) then Freeze_And_Append (Atype, N, Result); end if; -- Freeze base type before freezing the entity (RM 13.14(15)) if E /= Base_Type (E) then Freeze_And_Append (Base_Type (E), N, Result); end if; end if; -- A subtype inherits all the type-related representation aspects -- from its parents (RM 13.1(8)). Inherit_Aspects_At_Freeze_Point (E); -- For a derived type, freeze its parent type first (RM 13.14(15)) elsif Is_Derived_Type (E) then Freeze_And_Append (Etype (E), N, Result); Freeze_And_Append (First_Subtype (Etype (E)), N, Result); -- A derived type inherits each type-related representation aspect -- of its parent type that was directly specified before the -- declaration of the derived type (RM 13.1(15)). Inherit_Aspects_At_Freeze_Point (E); end if; -- Check for incompatible size and alignment for record type if Warn_On_Size_Alignment and then Is_Record_Type (E) and then Has_Size_Clause (E) and then Has_Alignment_Clause (E) -- If explicit Object_Size clause given assume that the programmer -- knows what he is doing, and expects the compiler behavior. and then not Has_Object_Size_Clause (E) -- Check for size not a multiple of alignment and then RM_Size (E) mod (Alignment (E) * System_Storage_Unit) /= 0 then declare SC : constant Node_Id := Size_Clause (E); AC : constant Node_Id := Alignment_Clause (E); Loc : Node_Id; Abits : constant Uint := Alignment (E) * System_Storage_Unit; begin if Present (SC) and then Present (AC) then -- Give a warning if Sloc (SC) > Sloc (AC) then Loc := SC; Error_Msg_NE ("?Z?size is not a multiple of alignment for &", Loc, E); Error_Msg_Sloc := Sloc (AC); Error_Msg_Uint_1 := Alignment (E); Error_Msg_N ("\?Z?alignment of ^ specified #", Loc); else Loc := AC; Error_Msg_NE ("?Z?size is not a multiple of alignment for &", Loc, E); Error_Msg_Sloc := Sloc (SC); Error_Msg_Uint_1 := RM_Size (E); Error_Msg_N ("\?Z?size of ^ specified #", Loc); end if; Error_Msg_Uint_1 := ((RM_Size (E) / Abits) + 1) * Abits; Error_Msg_N ("\?Z?Object_Size will be increased to ^", Loc); end if; end; end if; -- Array type if Is_Array_Type (E) then Freeze_Array_Type (E); -- 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), N, Result); -- If the base type of the class-wide type is still incomplete, -- the class-wide remains unfrozen as well. This is legal when -- E is the formal of a primitive operation of some other type -- which is being frozen. if not Is_Frozen (Root_Type (E)) then Set_Is_Frozen (E, False); goto Leave; end if; -- The equivalent type associated with a class-wide subtype needs -- to be frozen to ensure that its layout is done. if Ekind (E) = E_Class_Wide_Subtype and then Present (Equivalent_Type (E)) then Freeze_And_Append (Equivalent_Type (E), N, Result); end if; -- Generate an itype reference for a library-level class-wide type -- at the freeze point. Otherwise the first explicit reference to -- the type may appear 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); -- From a gigi point of view, a class-wide subtype derives -- from its record equivalent type. As a result, the itype -- reference must appear after the freeze node of the -- equivalent type or gigi will reject the reference. if Ekind (E) = E_Class_Wide_Subtype and then Present (Equivalent_Type (E)) then Insert_After (Freeze_Node (Equivalent_Type (E)), Ref); else Add_To_Result (Ref); end if; end; end if; -- For a record type or record subtype, freeze all 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_In (E, E_Record_Type, E_Record_Subtype) then if not In_Generic_Scope (E) then Freeze_Record_Type (E); end if; -- Report a warning if a discriminated record base type has a -- convention with language C or C++ applied to it. This check is -- done even within generic scopes (but not in instantiations), -- which is why we don't do it as part of Freeze_Record_Type. Check_Suspicious_Convention (E); -- For a concurrent type, freeze corresponding record type. This does -- not correspond to any specific rule in the RM, but the record type -- is essentially part of the concurrent type. Also freeze 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), N, Result); end if; Comp := First_Entity (E); while Present (Comp) loop if Is_Type (Comp) then Freeze_And_Append (Comp, N, Result); elsif (Ekind (Comp)) /= E_Function then -- The guard on the presence of the Etype seems to be needed -- for some CodePeer (-gnatcC) cases, but not clear why??? if Present (Etype (Comp)) 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), N, Result); end if; 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). -- If the full view is itself private, the above requirements apply -- to the underlying full view instead of the full view. But there is -- no swapping mechanism for the underlying full view so we need to -- set the pointers appropriately in both cases. elsif Is_Incomplete_Or_Private_Type (E) and then not Is_Generic_Type (E) then -- The construction of the dispatch table associated with library -- level tagged types forces freezing of all the primitives of the -- type, which may cause premature freezing of the partial view. -- For example: -- package Pkg is -- type T is tagged private; -- type DT is new T with private; -- procedure Prim (X : in out T; Y : in out DT'Class); -- private -- type T is tagged null record; -- Obj : T; -- type DT is new T with null record; -- end; -- In this case the type will be frozen later by the usual -- mechanism: an object declaration, an instantiation, or the -- end of a declarative part. if Is_Library_Level_Tagged_Type (E) and then not Present (Full_View (E)) then Set_Is_Frozen (E, False); goto Leave; -- Case of full view present elsif 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); -- Otherwise freeze full view and patch the pointers so that -- the freeze node will elaborate both views in the back end. -- However, if full view is itself private, freeze underlying -- full view instead and patch the pointers so that the freeze -- node will elaborate the three views in the back end. else declare Full : Entity_Id := Full_View (E); begin if Is_Private_Type (Full) and then Present (Underlying_Full_View (Full)) then Full := Underlying_Full_View (Full); end if; Freeze_And_Append (Full, N, Result); if Full /= Full_View (E) and then Has_Delayed_Freeze (Full_View (E)) then F_Node := Freeze_Node (Full); if Present (F_Node) then Inherit_Freeze_Node (Fnod => F_Node, Typ => Full_View (E)); else Set_Has_Delayed_Freeze (Full_View (E), False); Set_Freeze_Node (Full_View (E), Empty); end if; end if; if Has_Delayed_Freeze (E) then F_Node := Freeze_Node (Full_View (E)); if Present (F_Node) then Inherit_Freeze_Node (Fnod => F_Node, Typ => 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; end if; Check_Debug_Info_Needed (E); -- 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; goto Leave; -- Case of underlying full view present elsif Is_Private_Type (E) and then Present (Underlying_Full_View (E)) then if not Is_Frozen (Underlying_Full_View (E)) then Freeze_And_Append (Underlying_Full_View (E), N, Result); end if; -- Patch the pointers so that the freeze node will elaborate -- both views in the back end. if Has_Delayed_Freeze (E) then F_Node := Freeze_Node (Underlying_Full_View (E)); if Present (F_Node) then Inherit_Freeze_Node (Fnod => F_Node, Typ => E); else Set_Has_Delayed_Freeze (E, False); Set_Freeze_Node (E, Empty); end if; end if; Check_Debug_Info_Needed (E); goto Leave; -- 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); Result := No_List; goto Leave; end if; -- For access subprogram, freeze types of all formals, the return -- type was already frozen, since it is the Etype of the function. -- Formal types can be tagged Taft amendment types, but otherwise -- they cannot be incomplete. elsif Ekind (E) = E_Subprogram_Type then Formal := First_Formal (E); while Present (Formal) loop if Ekind (Etype (Formal)) = E_Incomplete_Type and then No (Full_View (Etype (Formal))) then if Is_Tagged_Type (Etype (Formal)) then null; -- AI05-151: Incomplete types are allowed in access to -- subprogram specifications. elsif Ada_Version < Ada_2012 then Error_Msg_NE ("invalid use of incomplete type&", E, Etype (Formal)); end if; end if; Freeze_And_Append (Etype (Formal), N, Result); Next_Formal (Formal); end loop; Freeze_Subprogram (E); -- 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 Is_Access_Protected_Subprogram_Type (E) then if Present (Equivalent_Type (E)) then Freeze_And_Append (Equivalent_Type (E), N, 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 goto Leave; 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 Is_Base_Type (E) then if Small_Value (E) < Ureal_2_M_80 then Error_Msg_Name_1 := Name_Small; Error_Msg_N ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E); elsif Small_Value (E) > Ureal_2_80 then Error_Msg_Name_1 := Name_Small; Error_Msg_N ("`&''%` too large, maximum allowed 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 ("`&''%` too small, minimum allowed 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 ("`&''%` too large, maximum allowed 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); if Is_Modular_Integer_Type (E) and then Warn_On_Suspicious_Modulus_Value then Check_Suspicious_Modulus (E); end if; -- The pool applies to named and anonymous access types, but not -- to subprogram and to internal types generated for 'Access -- references. elsif Is_Access_Type (E) and then not Is_Access_Subprogram_Type (E) and then Ekind (E) /= E_Access_Attribute_Type then -- If a pragma Default_Storage_Pool applies, and this type has no -- Storage_Pool or Storage_Size clause (which must have occurred -- before the freezing point), then use the default. This applies -- only to base types. -- None of this applies to access to subprograms, for which there -- are clearly no pools. if Present (Default_Pool) and then Is_Base_Type (E) and then not Has_Storage_Size_Clause (E) and then No (Associated_Storage_Pool (E)) then -- Case of pragma Default_Storage_Pool (null) if Nkind (Default_Pool) = N_Null then Set_No_Pool_Assigned (E); -- Case of pragma Default_Storage_Pool (storage_pool_NAME) else Set_Associated_Storage_Pool (E, Entity (Default_Pool)); end if; end if; -- 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_2005 or else not No_Pool_Assigned (E)) and then not Is_Generic_Unit (Scope (E)) then Error_Msg_N ("named access type not allowed in pure unit", E); if Ada_Version >= Ada_2005 then Error_Msg_N ("\would be legal if Storage_Size of 0 given??", E); elsif No_Pool_Assigned (E) then Error_Msg_N ("\would be legal in Ada 2005??", E); else Error_Msg_N ("\would be legal in Ada 2005 if " & "Storage_Size of 0 given??", E); end if; 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; -- If the type is a simple storage pool type, then this is where -- we attempt to locate and validate its Allocate, Deallocate, and -- Storage_Size operations (the first is required, and the latter -- two are optional). We also verify that the full type for a -- private type is allowed to be a simple storage pool type. if Present (Get_Rep_Pragma (E, Name_Simple_Storage_Pool_Type)) and then (Is_Base_Type (E) or else Has_Private_Declaration (E)) then -- If the type is marked Has_Private_Declaration, then this is -- a full type for a private type that was specified with the -- pragma Simple_Storage_Pool_Type, and here we ensure that the -- pragma is allowed for the full type (for example, it can't -- be an array type, or a nonlimited record type). if Has_Private_Declaration (E) then if (not Is_Record_Type (E) or else not Is_Limited_View (E)) and then not Is_Private_Type (E) then Error_Msg_Name_1 := Name_Simple_Storage_Pool_Type; Error_Msg_N ("pragma% can only apply to full type that is an " & "explicitly limited type", E); end if; end if; Validate_Simple_Pool_Ops : declare Pool_Type : Entity_Id renames E; Address_Type : constant Entity_Id := RTE (RE_Address); Stg_Cnt_Type : constant Entity_Id := RTE (RE_Storage_Count); procedure Validate_Simple_Pool_Op_Formal (Pool_Op : Entity_Id; Pool_Op_Formal : in out Entity_Id; Expected_Mode : Formal_Kind; Expected_Type : Entity_Id; Formal_Name : String; OK_Formal : in out Boolean); -- Validate one formal Pool_Op_Formal of the candidate pool -- operation Pool_Op. The formal must be of Expected_Type -- and have mode Expected_Mode. OK_Formal will be set to -- False if the formal doesn't match. If OK_Formal is False -- on entry, then the formal will effectively be ignored -- (because validation of the pool op has already failed). -- Upon return, Pool_Op_Formal will be updated to the next -- formal, if any. procedure Validate_Simple_Pool_Operation (Op_Name : Name_Id); -- Search for and validate a simple pool operation with the -- name Op_Name. If the name is Allocate, then there must be -- exactly one such primitive operation for the simple pool -- type. If the name is Deallocate or Storage_Size, then -- there can be at most one such primitive operation. The -- profile of the located primitive must conform to what -- is expected for each operation. ------------------------------------ -- Validate_Simple_Pool_Op_Formal -- ------------------------------------ procedure Validate_Simple_Pool_Op_Formal (Pool_Op : Entity_Id; Pool_Op_Formal : in out Entity_Id; Expected_Mode : Formal_Kind; Expected_Type : Entity_Id; Formal_Name : String; OK_Formal : in out Boolean) is begin -- If OK_Formal is False on entry, then simply ignore -- the formal, because an earlier formal has already -- been flagged. if not OK_Formal then return; -- If no formal is passed in, then issue an error for a -- missing formal. elsif not Present (Pool_Op_Formal) then Error_Msg_NE ("simple storage pool op missing formal " & Formal_Name & " of type&", Pool_Op, Expected_Type); OK_Formal := False; return; end if; if Etype (Pool_Op_Formal) /= Expected_Type then -- If the pool type was expected for this formal, then -- this will not be considered a candidate operation -- for the simple pool, so we unset OK_Formal so that -- the op and any later formals will be ignored. if Expected_Type = Pool_Type then OK_Formal := False; return; else Error_Msg_NE ("wrong type for formal " & Formal_Name & " of simple storage pool op; expected type&", Pool_Op_Formal, Expected_Type); end if; end if; -- Issue error if formal's mode is not the expected one if Ekind (Pool_Op_Formal) /= Expected_Mode then Error_Msg_N ("wrong mode for formal of simple storage pool op", Pool_Op_Formal); end if; -- Advance to the next formal Next_Formal (Pool_Op_Formal); end Validate_Simple_Pool_Op_Formal; ------------------------------------ -- Validate_Simple_Pool_Operation -- ------------------------------------ procedure Validate_Simple_Pool_Operation (Op_Name : Name_Id) is Op : Entity_Id; Found_Op : Entity_Id := Empty; Formal : Entity_Id; Is_OK : Boolean; begin pragma Assert (Nam_In (Op_Name, Name_Allocate, Name_Deallocate, Name_Storage_Size)); Error_Msg_Name_1 := Op_Name; -- For each homonym declared immediately in the scope -- of the simple storage pool type, determine whether -- the homonym is an operation of the pool type, and, -- if so, check that its profile is as expected for -- a simple pool operation of that name. Op := Get_Name_Entity_Id (Op_Name); while Present (Op) loop if Ekind_In (Op, E_Function, E_Procedure) and then Scope (Op) = Current_Scope then Formal := First_Entity (Op); Is_OK := True; -- The first parameter must be of the pool type -- in order for the operation to qualify. if Op_Name = Name_Storage_Size then Validate_Simple_Pool_Op_Formal (Op, Formal, E_In_Parameter, Pool_Type, "Pool", Is_OK); else Validate_Simple_Pool_Op_Formal (Op, Formal, E_In_Out_Parameter, Pool_Type, "Pool", Is_OK); end if; -- If another operation with this name has already -- been located for the type, then flag an error, -- since we only allow the type to have a single -- such primitive. if Present (Found_Op) and then Is_OK then Error_Msg_NE ("only one % operation allowed for " & "simple storage pool type&", Op, Pool_Type); end if; -- In the case of Allocate and Deallocate, a formal -- of type System.Address is required. if Op_Name = Name_Allocate then Validate_Simple_Pool_Op_Formal (Op, Formal, E_Out_Parameter, Address_Type, "Storage_Address", Is_OK); elsif Op_Name = Name_Deallocate then Validate_Simple_Pool_Op_Formal (Op, Formal, E_In_Parameter, Address_Type, "Storage_Address", Is_OK); end if; -- In the case of Allocate and Deallocate, formals -- of type Storage_Count are required as the third -- and fourth parameters. if Op_Name /= Name_Storage_Size then Validate_Simple_Pool_Op_Formal (Op, Formal, E_In_Parameter, Stg_Cnt_Type, "Size_In_Storage_Units", Is_OK); Validate_Simple_Pool_Op_Formal (Op, Formal, E_In_Parameter, Stg_Cnt_Type, "Alignment", Is_OK); end if; -- If no mismatched formals have been found (Is_OK) -- and no excess formals are present, then this -- operation has been validated, so record it. if not Present (Formal) and then Is_OK then Found_Op := Op; end if; end if; Op := Homonym (Op); end loop; -- There must be a valid Allocate operation for the type, -- so issue an error if none was found. if Op_Name = Name_Allocate and then not Present (Found_Op) then Error_Msg_N ("missing % operation for simple " & "storage pool type", Pool_Type); elsif Present (Found_Op) then -- Simple pool operations can't be abstract if Is_Abstract_Subprogram (Found_Op) then Error_Msg_N ("simple storage pool operation must not be " & "abstract", Found_Op); end if; -- The Storage_Size operation must be a function with -- Storage_Count as its result type. if Op_Name = Name_Storage_Size then if Ekind (Found_Op) = E_Procedure then Error_Msg_N ("% operation must be a function", Found_Op); elsif Etype (Found_Op) /= Stg_Cnt_Type then Error_Msg_NE ("wrong result type for%, expected type&", Found_Op, Stg_Cnt_Type); end if; -- Allocate and Deallocate must be procedures elsif Ekind (Found_Op) = E_Function then Error_Msg_N ("% operation must be a procedure", Found_Op); end if; end if; end Validate_Simple_Pool_Operation; -- Start of processing for Validate_Simple_Pool_Ops begin Validate_Simple_Pool_Operation (Name_Allocate); Validate_Simple_Pool_Operation (Name_Deallocate); Validate_Simple_Pool_Operation (Name_Storage_Size); end Validate_Simple_Pool_Ops; end if; 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 alignment 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 -- Suppress 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; -- Now we 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. Ditto for types declared within a generic unit, -- which may have components that depend on generic parameters, and -- that will be recreated in an instance. if Inside_A_Generic then null; -- Otherwise we call the layout procedure else Layout_Type (E); end if; -- If this is an access to subprogram whose designated type is itself -- a subprogram type, the return type of this anonymous subprogram -- type must be decorated as well. if Ekind (E) = E_Anonymous_Access_Subprogram_Type and then Ekind (Designated_Type (E)) = E_Subprogram_Type then Layout_Type (Etype (Designated_Type (E))); end if; -- If the type has a Defaut_Value/Default_Component_Value aspect, -- this is where we analye the expression (after the type is frozen, -- since in the case of Default_Value, we are analyzing with the -- type itself, and we treat Default_Component_Value similarly for -- the sake of uniformity). if Is_First_Subtype (E) and then Has_Default_Aspect (E) then declare Nam : Name_Id; Exp : Node_Id; Typ : Entity_Id; begin if Is_Scalar_Type (E) then Nam := Name_Default_Value; Typ := E; Exp := Default_Aspect_Value (Typ); else Nam := Name_Default_Component_Value; Typ := Component_Type (E); Exp := Default_Aspect_Component_Value (E); end if; Analyze_And_Resolve (Exp, Typ); if Etype (Exp) /= Any_Type then if not Is_OK_Static_Expression (Exp) then Error_Msg_Name_1 := Nam; Flag_Non_Static_Expr ("aspect% requires static expression", Exp); end if; end if; end; 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); Add_To_Result (F_Node); -- 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), N, 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), N, 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); end if; end if; <<Leave>> Restore_Ghost_Region (Saved_GM, Saved_IGR); return Result; end Freeze_Entity; ----------------------------- -- Freeze_Enumeration_Type -- ----------------------------- procedure Freeze_Enumeration_Type (Typ : Entity_Id) is begin -- By default, if no size clause is present, an enumeration type with -- Convention C is assumed to interface to a C enum and has integer -- size, except for a boolean type because it is assumed to interface -- to _Bool introduced in C99. This applies to types. For subtypes, -- verify that its base type has no size clause either. Treat other -- foreign conventions in the same way, and also make sure alignment -- is set right. if Has_Foreign_Convention (Typ) and then not Is_Boolean_Type (Typ) and then not Has_Size_Clause (Typ) and then not Has_Size_Clause (Base_Type (Typ)) and then Esize (Typ) < Standard_Integer_Size -- Don't do this if Short_Enums on target and then not Target_Short_Enums then Init_Esize (Typ, Standard_Integer_Size); Set_Alignment (Typ, Alignment (Standard_Integer)); -- Normal Ada case or size clause present or not Long_C_Enums on target else -- If the enumeration type interfaces to C, and it has a size clause -- that specifies less than int size, it warrants a warning. The -- user may intend the C type to be an enum or a char, so this is -- not by itself an error that the Ada compiler can detect, but it -- it is a worth a heads-up. For Boolean and Character types we -- assume that the programmer has the proper C type in mind. if Convention (Typ) = Convention_C and then Has_Size_Clause (Typ) and then Esize (Typ) /= Esize (Standard_Integer) and then not Is_Boolean_Type (Typ) and then not Is_Character_Type (Typ) -- Don't do this if Short_Enums on target and then not Target_Short_Enums then Error_Msg_N ("C enum types have the size of a C int??", Size_Clause (Typ)); end if; Adjust_Esize_For_Alignment (Typ); end if; end Freeze_Enumeration_Type; ----------------------- -- Freeze_Expression -- ----------------------- procedure Freeze_Expression (N : Node_Id) is function Find_Aggregate_Component_Desig_Type return Entity_Id; -- If the expression is an array aggregate, the type of the component -- expressions is also frozen. If the component type is an access type -- and the expressions include allocators, the designed type is frozen -- as well. function In_Expanded_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, stream subprogram, or renaming as body). -- If so, this is not a freezing context. ----------------------------------------- -- Find_Aggregate_Component_Desig_Type -- ----------------------------------------- function Find_Aggregate_Component_Desig_Type return Entity_Id is Assoc : Node_Id; Exp : Node_Id; begin if Present (Expressions (N)) then Exp := First (Expressions (N)); while Present (Exp) loop if Nkind (Exp) = N_Allocator then return Designated_Type (Component_Type (Etype (N))); end if; Next (Exp); end loop; end if; if Present (Component_Associations (N)) then Assoc := First (Component_Associations (N)); while Present (Assoc) loop if Nkind (Expression (Assoc)) = N_Allocator then return Designated_Type (Component_Type (Etype (N))); end if; Next (Assoc); end loop; end if; return Empty; end Find_Aggregate_Component_Desig_Type; ---------------------- -- In_Expanded_Body -- ---------------------- function In_Expanded_Body (N : Node_Id) return Boolean is P : Node_Id; Id : Entity_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 Id := Defining_Unit_Name (Specification (P)); -- The following are expander-created bodies, or bodies that -- are not freeze points. if Nkind (Id) = N_Defining_Identifier and then (Is_Init_Proc (Id) or else Is_TSS (Id, TSS_Stream_Input) or else Is_TSS (Id, TSS_Stream_Output) or else Is_TSS (Id, TSS_Stream_Read) or else Is_TSS (Id, TSS_Stream_Write) or else Nkind_In (Original_Node (P), N_Subprogram_Renaming_Declaration, N_Expression_Function)) then return True; else return False; end if; end if; end In_Expanded_Body; -- Local variables In_Spec_Exp : constant Boolean := In_Spec_Expression; Desig_Typ : Entity_Id; Nam : Entity_Id; P : Node_Id; Parent_P : Node_Id; Typ : Entity_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. Freeze_Outside_Subp : Entity_Id := Empty; -- This entity is set if we are inside a subprogram body and the frozen -- entity is defined in the enclosing scope of this subprogram. In such -- case we must skip the subprogram body when climbing the parents chain -- to locate the correct placement for the freezing node. -- 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_OK_Static_Expression). However, we -- exclude the case of the prefix of an attribute of a static scalar -- subtype from this early return, because static subtype attributes -- should always cause freezing, even in default expressions, but -- the attribute may not have been marked as static yet (because in -- Resolve_Attribute, the call to Eval_Attribute follows the call of -- Freeze_Expression on the prefix). if In_Spec_Exp and then Nkind (N) in N_Subexpr and then not Is_OK_Static_Expression (N) and then (Nkind (Parent (N)) /= N_Attribute_Reference or else not (Is_Entity_Name (N) and then Is_Type (Entity (N)) and then Is_OK_Static_Subtype (Entity (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); if Present (Nam) and then Ekind (Nam) = E_Function then Check_Expression_Function (N, Nam); end if; 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. -- For a function, we freeze the entity when the subprogram declaration -- is frozen, but a function call may appear in an initialization proc. -- before the declaration is frozen. We need to generate the extra -- formals, if any, to ensure that the expansion of the call includes -- the proper actuals. This only applies to Ada subprograms, not to -- imported ones. 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 -- Check whether aggregate includes allocators Desig_Typ := Find_Aggregate_Component_Desig_Type; end if; when N_Indexed_Component | N_Selected_Component | N_Slice => if Is_Access_Type (Etype (Prefix (N))) then Desig_Typ := Designated_Type (Etype (Prefix (N))); end if; when N_Identifier => if Present (Nam) and then Ekind (Nam) = E_Function and then Nkind (Parent (N)) = N_Function_Call and then Convention (Nam) = Convention_Ada then Create_Extra_Formals (Nam); 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; -- Check if we are inside a subprogram body and the frozen entity is -- defined in the enclosing scope of this subprogram. In such case we -- must skip the subprogram when climbing the parents chain to locate -- the correct placement for the freezing node. -- This is not needed for default expressions and other spec expressions -- in generic units since the Move_Freeze_Nodes mechanism (sem_ch12.adb) -- takes care of placing them at the proper place, after the generic -- unit. if Present (Nam) and then Scope (Nam) /= Current_Scope and then not (In_Spec_Exp and then Inside_A_Generic) then declare S : Entity_Id := Current_Scope; begin while Present (S) and then In_Same_Source_Unit (Nam, S) loop if Scope (S) = Scope (Nam) then if Is_Subprogram (S) and then Has_Completion (S) then Freeze_Outside_Subp := S; end if; exit; end if; S := Scope (S); end loop; end; end if; -- Examine the enclosing context by climbing the parent chain -- If we identified that we must freeze the entity outside of a given -- subprogram then we just climb up to that subprogram checking if some -- enclosing node is marked as Must_Not_Freeze (since in such case we -- must not freeze yet this entity). P := N; if Present (Freeze_Outside_Subp) then loop -- Do not freeze the current expression if another expression in -- the chain of parents must not be frozen. if Nkind (P) in N_Subexpr and then Must_Not_Freeze (P) then return; end if; 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. if No (Parent_P) then return; end if; exit when Nkind (Parent_P) = N_Subprogram_Body and then Unique_Defining_Entity (Parent_P) = Freeze_Outside_Subp; P := Parent_P; end loop; -- Otherwise the traversal serves two purposes - to detect scenarios -- where freezeing is not needed and to find the proper insertion point -- for the freeze nodes. Although somewhat similar to Insert_Actions, -- this traversal is freezing semantics-sensitive. Inserting freeze -- nodes blindly in the tree may result in types being frozen too early. else loop -- Do not freeze the current expression if another expression in -- the chain of parents must not be frozen. if Nkind (P) in N_Subexpr and then Must_Not_Freeze (P) then return; end if; 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_Spec_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_In (N, N_Identifier, 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-overloaded 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_Expanded_Body (Parent_P) then declare Subp : constant Node_Id := Parent (Parent_P); Spec : Entity_Id; begin -- Freeze the entity only when it is declared inside -- the body of the expander generated procedure. -- This case is recognized by the scope of the entity -- or its 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. if Nkind (Subp) = N_Subprogram_Body then Spec := Corresponding_Spec (Subp); if (Present (Typ) and then Scope (Typ) = Spec) or else (Present (Nam) and then Scope (Nam) = Spec) then exit; elsif Present (Typ) and then Scope (Typ) = Current_Scope and then Defining_Entity (Subp) = Current_Scope then exit; end if; end if; -- An expression function may act as a completion of -- a function declaration. As such, it can reference -- entities declared between the two views: -- Hidden []; -- 1 -- function F return ...; -- private -- function Hidden return ...; -- function F return ... is (Hidden); -- 2 -- Refering to the example above, freezing the -- expression of F (2) would place Hidden's freeze -- node (1) in the wrong place. Avoid explicit -- freezing and let the usual scenarios do the job -- (for example, reaching the end of the private -- declarations, or a call to F.) if Nkind (Original_Node (Subp)) = N_Expression_Function then null; -- Freeze outside the body else Parent_P := Parent (Parent_P); Freeze_Outside := True; end if; end; -- 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_Block_Statement | N_Entry_Body | N_Package_Body | N_Package_Specification | N_Protected_Body | N_Subprogram_Body | N_Task_Body => 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_Abortable_Part | N_Accept_Alternative | N_And_Then | N_Case_Statement_Alternative | N_Compilation_Unit_Aux | N_Conditional_Entry_Call | N_Delay_Alternative | N_Elsif_Part | N_Entry_Call_Alternative | N_Exception_Handler | N_Extended_Return_Statement | N_Freeze_Entity | N_If_Statement | N_Or_Else | N_Selective_Accept | N_Triggering_Alternative => exit when Is_List_Member (P); -- Freeze nodes produced by an expression coming from the -- Actions list of a N_Expression_With_Actions node must remain -- within the Actions list. Inserting the freeze nodes further -- up the tree may lead to use before declaration issues in the -- case of array types. when N_Expression_With_Actions => if Is_List_Member (P) and then List_Containing (P) = Actions (Parent_P) then exit; end if; -- Note: 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; end if; -- 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 and other spec 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_Spec_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 N : constant Node_Id := Current_Scope; Freeze_Nodes : List_Id := No_List; Pos : Int := Scope_Stack.Last; begin if Present (Desig_Typ) then Freeze_And_Append (Desig_Typ, N, Freeze_Nodes); end if; if Present (Typ) then Freeze_And_Append (Typ, N, Freeze_Nodes); end if; if Present (Nam) then Freeze_And_Append (Nam, N, Freeze_Nodes); end if; -- The current scope may be that of a constrained component of -- an enclosing record declaration, or of a loop of an enclosing -- quantified expression, which is above the current scope in the -- scope stack. Indeed in the context of a quantified expression, -- a scope is created and pushed above the current scope in order -- to emulate the loop-like behavior of the quantified expression. -- If the expression is within a top-level pragma, as for a pre- -- condition on a library-level subprogram, nothing to do. if not Is_Compilation_Unit (Current_Scope) and then (Is_Record_Type (Scope (Current_Scope)) or else Nkind (Parent (Current_Scope)) = N_Quantified_Expression) 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 spec-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_Spec_Expression mode to propagate these freeze actions. -- This also means they get properly analyzed and expanded. In_Spec_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; -- Restore In_Spec_Expression flag In_Spec_Expression := In_Spec_Exp; end Freeze_Expression; ----------------------- -- Freeze_Expr_Types -- ----------------------- procedure Freeze_Expr_Types (Def_Id : Entity_Id; Typ : Entity_Id; Expr : Node_Id; N : Node_Id) is function Cloned_Expression return Node_Id; -- Build a duplicate of the expression of the return statement that has -- no defining entities shared with the original expression. function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result; -- Freeze all types referenced in the subtree rooted at Node ----------------------- -- Cloned_Expression -- ----------------------- function Cloned_Expression return Node_Id is function Clone_Id (Node : Node_Id) return Traverse_Result; -- Tree traversal routine that clones the defining identifier of -- iterator and loop parameter specification nodes. -------------- -- Clone_Id -- -------------- function Clone_Id (Node : Node_Id) return Traverse_Result is begin if Nkind_In (Node, N_Iterator_Specification, N_Loop_Parameter_Specification) then Set_Defining_Identifier (Node, New_Copy (Defining_Identifier (Node))); end if; return OK; end Clone_Id; procedure Clone_Def_Ids is new Traverse_Proc (Clone_Id); -- Local variable Dup_Expr : constant Node_Id := New_Copy_Tree (Expr); -- Start of processing for Cloned_Expression begin -- We must duplicate the expression with semantic information to -- inherit the decoration of global entities in generic instances. -- Set the parent of the new node to be the parent of the original -- to get the proper context, which is needed for complete error -- reporting and for semantic analysis. Set_Parent (Dup_Expr, Parent (Expr)); -- Replace the defining identifier of iterators and loop param -- specifications by a clone to ensure that the cloned expression -- and the original expression don't have shared identifiers; -- otherwise, as part of the preanalysis of the expression, these -- shared identifiers may be left decorated with itypes which -- will not be available in the tree passed to the backend. Clone_Def_Ids (Dup_Expr); return Dup_Expr; end Cloned_Expression; ---------------------- -- Freeze_Type_Refs -- ---------------------- function Freeze_Type_Refs (Node : Node_Id) return Traverse_Result is procedure Check_And_Freeze_Type (Typ : Entity_Id); -- Check that Typ is fully declared and freeze it if so --------------------------- -- Check_And_Freeze_Type -- --------------------------- procedure Check_And_Freeze_Type (Typ : Entity_Id) is begin -- Skip Itypes created by the preanalysis, and itypes whose -- scope is another type (i.e. component subtypes that depend -- on a discriminant), if Is_Itype (Typ) and then (Scope_Within_Or_Same (Scope (Typ), Def_Id) or else Is_Type (Scope (Typ))) then return; end if; -- This provides a better error message than generating primitives -- whose compilation fails much later. Refine the error message if -- possible. Check_Fully_Declared (Typ, Node); if Error_Posted (Node) then if Has_Private_Component (Typ) and then not Is_Private_Type (Typ) then Error_Msg_NE ("\type& has private component", Node, Typ); end if; else Freeze_Before (N, Typ); end if; end Check_And_Freeze_Type; -- Start of processing for Freeze_Type_Refs begin -- Check that a type referenced by an entity can be frozen if Is_Entity_Name (Node) and then Present (Entity (Node)) then Check_And_Freeze_Type (Etype (Entity (Node))); -- Check that the enclosing record type can be frozen if Ekind_In (Entity (Node), E_Component, E_Discriminant) then Check_And_Freeze_Type (Scope (Entity (Node))); end if; -- Freezing an access type does not freeze the designated type, but -- freezing conversions between access to interfaces requires that -- the interface types themselves be frozen, so that dispatch table -- entities are properly created. -- Unclear whether a more general rule is needed ??? elsif Nkind (Node) = N_Type_Conversion and then Is_Access_Type (Etype (Node)) and then Is_Interface (Designated_Type (Etype (Node))) then Check_And_Freeze_Type (Designated_Type (Etype (Node))); end if; -- An implicit dereference freezes the designated type. In the case -- of a dispatching call whose controlling argument is an access -- type, the dereference is not made explicit, so we must check for -- such a call and freeze the designated type. if Nkind (Node) in N_Has_Etype and then Present (Etype (Node)) and then Is_Access_Type (Etype (Node)) and then Nkind (Parent (Node)) = N_Function_Call and then Node = Controlling_Argument (Parent (Node)) then Check_And_Freeze_Type (Designated_Type (Etype (Node))); end if; -- No point in posting several errors on the same expression if Serious_Errors_Detected > 0 then return Abandon; else return OK; end if; end Freeze_Type_Refs; procedure Freeze_References is new Traverse_Proc (Freeze_Type_Refs); -- Local variables Saved_First_Entity : constant Entity_Id := First_Entity (Def_Id); Saved_Last_Entity : constant Entity_Id := Last_Entity (Def_Id); Dup_Expr : constant Node_Id := Cloned_Expression; -- Start of processing for Freeze_Expr_Types begin -- Preanalyze a duplicate of the expression to have available the -- minimum decoration needed to locate referenced unfrozen types -- without adding any decoration to the function expression. -- This routine is also applied to expressions in the contract for -- the subprogram. If that happens when expanding the code for -- pre/postconditions during expansion of the subprogram body, the -- subprogram is already installed. if Def_Id /= Current_Scope then Push_Scope (Def_Id); Install_Formals (Def_Id); Preanalyze_Spec_Expression (Dup_Expr, Typ); End_Scope; else Preanalyze_Spec_Expression (Dup_Expr, Typ); end if; -- Restore certain attributes of Def_Id since the preanalysis may -- have introduced itypes to this scope, thus modifying attributes -- First_Entity and Last_Entity. Set_First_Entity (Def_Id, Saved_First_Entity); Set_Last_Entity (Def_Id, Saved_Last_Entity); if Present (Last_Entity (Def_Id)) then Set_Next_Entity (Last_Entity (Def_Id), Empty); end if; -- Freeze all types referenced in the expression Freeze_References (Dup_Expr); end Freeze_Expr_Types; ----------------------------- -- 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; Orig_Lo : Ureal; Orig_Hi : Ureal; -- Save original bounds (for shaving tests) Actual_Size : Nat; -- Actual size chosen 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 -- The type, or its first subtype if we are freezing the anonymous -- base, may have a delayed Small aspect. It must be analyzed now, -- so that all characteristics of the type (size, bounds) can be -- computed and validated in the call to Minimum_Size that follows. if Has_Delayed_Aspects (First_Subtype (Typ)) then Analyze_Aspects_At_Freeze_Point (First_Subtype (Typ)); Set_Has_Delayed_Aspects (First_Subtype (Typ), False); end if; -- 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); Orig_Lo := Loval; Orig_Hi := Hival; -- 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 accommodated 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; -- If the value went from negative to zero, then we have the -- case where Loval_Incl_EP is the model number just below -- zero, so we want to stick to the negative value for the -- base type to maintain the condition that the size will -- include signed values. if Typ = Btyp and then UR_Is_Zero (Loval_Excl_EP) then Loval_Excl_EP := Loval_Incl_EP; end if; 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 Addressable (Size_Excl_EP) 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 allowed 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 allowed 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 allowed is ^", Size_Clause (Typ), Typ); end if; else Set_RM_Size (Typ, Minsiz); end if; end; -- Check for shaving if Comes_From_Source (Typ) then -- In SPARK mode the given bounds must be strictly representable if SPARK_Mode = On then if Orig_Lo < Expr_Value_R (Lo) then Error_Msg_NE ("declared low bound of type & is outside type range", Lo, Typ); end if; if Orig_Hi > Expr_Value_R (Hi) then Error_Msg_NE ("declared high bound of type & is outside type range", Hi, Typ); end if; else if Orig_Lo < Expr_Value_R (Lo) then Error_Msg_N ("declared low bound of type & is outside type range??", Typ); Error_Msg_N ("\low bound adjusted up by delta (RM 3.5.9(13))??", Typ); end if; if Orig_Hi > Expr_Value_R (Hi) then Error_Msg_N ("declared high bound of type & is outside type range??", Typ); Error_Msg_N ("\high bound adjusted down by delta (RM 3.5.9(13))??", Typ); end if; end if; end if; 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, 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_OK_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)); exception when Cannot_Be_Static => -- If the object that cannot be static is imported or exported, then -- issue an error message saying that this object cannot be imported -- or exported. If it has an address clause it is an overlay in the -- current partition and the static requirement is not relevant. -- Do not issue any error message when ignoring rep clauses. if Ignore_Rep_Clauses then null; elsif Is_Imported (E) then if No (Address_Clause (E)) then Error_Msg_N ("& cannot be imported (local type is not constant)", E); end if; -- 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 procedure Set_Profile_Convention (Subp_Id : Entity_Id); -- Set the conventions of all anonymous access-to-subprogram formals and -- result subtype of subprogram Subp_Id to the convention of Subp_Id. ---------------------------- -- Set_Profile_Convention -- ---------------------------- procedure Set_Profile_Convention (Subp_Id : Entity_Id) is Conv : constant Convention_Id := Convention (Subp_Id); procedure Set_Type_Convention (Typ : Entity_Id); -- Set the convention of anonymous access-to-subprogram type Typ and -- its designated type to Conv. ------------------------- -- Set_Type_Convention -- ------------------------- procedure Set_Type_Convention (Typ : Entity_Id) is begin -- Set the convention on both the anonymous access-to-subprogram -- type and the subprogram type it points to because both types -- participate in conformance-related checks. if Ekind (Typ) = E_Anonymous_Access_Subprogram_Type then Set_Convention (Typ, Conv); Set_Convention (Designated_Type (Typ), Conv); end if; end Set_Type_Convention; -- Local variables Formal : Entity_Id; -- Start of processing for Set_Profile_Convention begin Formal := First_Formal (Subp_Id); while Present (Formal) loop Set_Type_Convention (Etype (Formal)); Next_Formal (Formal); end loop; if Ekind (Subp_Id) = E_Function then Set_Type_Convention (Etype (Subp_Id)); end if; end Set_Profile_Convention; -- Local variables F : Entity_Id; Retype : Entity_Id; -- Start of processing for Freeze_Subprogram 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 or the subprogram is an -- intrinsic. 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. -- The reason for the intrinsic exception is that in general, intrinsic -- functions (such as shifts) are pure anyway. The only exceptions are -- the intrinsics in GNAT.Source_Info, and that unit is not marked Pure -- in any case, so no problem arises. if Is_Imported (E) and then Is_Pure (E) and then not Has_Pragma_Pure_Function (E) and then not Is_Intrinsic_Subprogram (E) then Set_Is_Pure (E, False); end if; -- We also reset the Pure indication on a subprogram with an Address -- parameter, because the parameter may be used as a pointer and the -- referenced data may change even if the address value does not. -- Note that if the programmer gave an explicit Pure_Function pragma, -- then we believe the programmer, and leave the subprogram Pure. We -- also suppress this check on run-time files. if Is_Pure (E) and then Is_Subprogram (E) and then not Has_Pragma_Pure_Function (E) and then not Is_Internal_Unit (Current_Sem_Unit) then Check_Function_With_Address_Parameter (E); end if; -- Ensure that all anonymous access-to-subprogram types inherit the -- convention of their related subprogram (RM 6.3.1 13.1/3). This is -- not done for a defaulted convention Ada because those types also -- default to Ada. Convention Protected must not be propagated when -- the subprogram is an entry because this would be illegal. The only -- way to force convention Protected on these kinds of types is to -- include keyword "protected" in the access definition. if Convention (E) /= Convention_Ada and then Convention (E) /= Convention_Protected then Set_Profile_Convention (E); 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 if No (Extra_Formals (E)) then Create_Extra_Formals (E); end if; 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 unconstrained array 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; -- Display warning if returning unconstrained array elsif Is_Array_Type (Retype) and then not Is_Constrained (Retype) -- Check appropriate warning is enabled (should we check for -- Warnings (Off) on specific entities here, probably so???) and then Warn_On_Export_Import then Error_Msg_N ("?x?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 ("?x?parameter cannot be defaulted in non-Ada call", Default_Value (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 Has_Pragma_Inline_Always (E) then Error_Msg_N ("pragma Inline_Always not allowed for dispatching subprograms", E); end if; -- Because of the implicit representation of inherited predefined -- operators in the front-end, the overriding status of the operation -- may be affected when a full view of a type is analyzed, and this is -- not captured by the analysis of the corresponding type declaration. -- Therefore the correctness of a not-overriding indicator must be -- rechecked when the subprogram is frozen. if Nkind (E) = N_Defining_Operator_Symbol and then not Error_Posted (Parent (E)) then Check_Overriding_Indicator (E, Empty, Is_Primitive (E)); end if; if Modify_Tree_For_C and then Nkind (Parent (E)) = N_Function_Specification and then Is_Array_Type (Etype (E)) and then Is_Constrained (Etype (E)) and then not Is_Unchecked_Conversion_Instance (E) and then not Rewritten_For_C (E) then Build_Procedure_Form (Unit_Declaration_Node (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; -- For the designated type of an access to subprogram, all types in -- the profile must be fully defined. elsif Ekind (T) = E_Subprogram_Type then declare F : Entity_Id; begin F := First_Formal (T); while Present (F) loop if not Is_Fully_Defined (Etype (F)) then return False; end if; Next_Formal (F); end loop; return Is_Fully_Defined (Etype (T)); end; else return not Is_Private_Type (T) or else Present (Full_View (Base_Type (T))); 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_In (Dcopy, N_Expanded_Name, N_Integer_Literal, N_Character_Literal, N_String_Literal, N_Real_Literal) or else (Nkind (Dcopy) = N_Attribute_Reference and then Attribute_Name (Dcopy) = Name_Null_Parameter) or else Known_Null (Dcopy) 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 is -- simpler to build a procedure than a function which might -- involve secondary stack expansion. else Dnam := Make_Temporary (Loc, '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_Temporary (Loc, 'T'), Object_Definition => New_Occurrence_Of (Etype (Formal), Loc), Expression => New_Copy_Tree (Dcopy))), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Empty_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_SSO_From_Default -- -------------------------- procedure Set_SSO_From_Default (T : Entity_Id) is Reversed : Boolean; begin -- Set default SSO for an array or record base type, except in case of -- a type extension (which always inherits the SSO of its parent type). if Is_Base_Type (T) and then (Is_Array_Type (T) or else (Is_Record_Type (T) and then not (Is_Tagged_Type (T) and then Is_Derived_Type (T)))) then Reversed := (Bytes_Big_Endian and then SSO_Set_Low_By_Default (T)) or else (not Bytes_Big_Endian and then SSO_Set_High_By_Default (T)); if (SSO_Set_Low_By_Default (T) or else SSO_Set_High_By_Default (T)) -- For a record type, if bit order is specified explicitly, -- then do not set SSO from default if not consistent. Note that -- we do not want to look at a Bit_Order attribute definition -- for a parent: if we were to inherit Bit_Order, then both -- SSO_Set_*_By_Default flags would have been cleared already -- (by Inherit_Aspects_At_Freeze_Point). and then not (Is_Record_Type (T) and then Has_Rep_Item (T, Name_Bit_Order, Check_Parents => False) and then Reverse_Bit_Order (T) /= Reversed) then -- If flags cause reverse storage order, then set the result. Note -- that we would have ignored the pragma setting the non default -- storage order in any case, hence the assertion at this point. pragma Assert (not Reversed or else Support_Nondefault_SSO_On_Target); Set_Reverse_Storage_Order (T, Reversed); -- For a record type, also set reversed bit order. Note: if a bit -- order has been specified explicitly, then this is a no-op. if Is_Record_Type (T) then Set_Reverse_Bit_Order (T, Reversed); end if; end if; end if; end Set_SSO_From_Default; ------------------ -- 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 unpleasant. 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 objects of access -- types with implicit null initialization, or when Normalize_Scalars -- applies and the type is scalar or a string type (the latter being -- tested for because predefined String types are initialized by inline -- code rather than by an init_proc). Note that we do not give the -- warning for Initialize_Scalars, since we suppressed initialization -- in this case. Also, do not warn if Suppress_Initialization is set -- either on the type, or on the object via pragma or aspect. if Present (Expr) and then not Is_Imported (Ent) and then not Initialization_Suppressed (Typ) and then not (Ekind (Ent) = E_Variable and then Initialization_Suppressed (Ent)) and then (Has_Non_Null_Base_Init_Proc (Typ) or else Is_Access_Type (Typ) or else (Normalize_Scalars and then (Is_Scalar_Type (Typ) or else Is_String_Type (Typ)))) 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; -- If a pragma Import follows, we assume that it is for the current -- target of the address clause, and skip the warning. There may be -- a source pragma or an aspect that specifies import and generates -- the corresponding pragma. These will indicate that the entity is -- imported and that is checked above so that the spurious warning -- (generated when the entity is frozen) will be suppressed. The -- pragma may be attached to the aspect, so it is not yet a list -- member. if Is_List_Member (Parent (Expr)) then Decl := Next (Parent (Expr)); if Present (Decl) and then Nkind (Decl) = N_Pragma and then Pragma_Name (Decl) = Name_Import then return; end if; end if; -- Otherwise give warning message 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_Impl_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 (RM B.1(24))??", Nam); end if; end Warn_Overlay; end Freeze;