URL
https://opencores.org/ocsvn/openrisc/openrisc/trunk
Subversion Repositories openrisc
[/] [openrisc/] [tags/] [gnu-dev/] [fsf-gcc-snapshot-1-mar-12/] [or1k-gcc/] [gcc/] [ada/] [freeze.adb] - Rev 706
Go to most recent revision | Compare with Previous | Blame | View Log
------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- F R E E Z E -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2012, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Atree; use Atree; with Debug; use Debug; with Einfo; use Einfo; with Elists; use Elists; with Errout; use Errout; with Exp_Ch3; use Exp_Ch3; with Exp_Ch7; use Exp_Ch7; with Exp_Disp; use Exp_Disp; with Exp_Pakd; use Exp_Pakd; with Exp_Util; use Exp_Util; with Exp_Tss; use Exp_Tss; 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_Ch6; use Sem_Ch6; with Sem_Ch7; use Sem_Ch7; with Sem_Ch8; use Sem_Ch8; with Sem_Ch13; use Sem_Ch13; with Sem_Eval; use Sem_Eval; with Sem_Mech; use Sem_Mech; with Sem_Prag; use Sem_Prag; with Sem_Res; use Sem_Res; with Sem_Util; use Sem_Util; with Sinfo; use Sinfo; with Snames; use Snames; with Stand; use Stand; with Targparm; use Targparm; with Tbuild; use Tbuild; with Ttypes; use Ttypes; with Uintp; use Uintp; with Urealp; use Urealp; package body Freeze is ----------------------- -- Local Subprograms -- ----------------------- procedure Adjust_Esize_For_Alignment (Typ : Entity_Id); -- Typ is a type that is being frozen. If no size clause is given, -- but a default Esize has been computed, then this default Esize is -- adjusted up if necessary to be consistent with a given alignment, -- but never to a value greater than Long_Long_Integer'Size. This -- is used for all discrete types and for fixed-point types. procedure Build_And_Analyze_Renamed_Body (Decl : Node_Id; New_S : Entity_Id; After : in out Node_Id); -- Build body for a renaming declaration, insert in tree and analyze procedure Check_Address_Clause (E : Entity_Id); -- Apply legality checks to address clauses for object declarations, -- at the point the object is frozen. procedure Check_Strict_Alignment (E : Entity_Id); -- E is a base type. If E is tagged or has a component that is aliased -- or tagged or contains something this is aliased or tagged, set -- Strict_Alignment. procedure Check_Unsigned_Type (E : Entity_Id); pragma Inline (Check_Unsigned_Type); -- If E is a fixed-point or discrete type, then all the necessary work -- to freeze it is completed except for possible setting of the flag -- Is_Unsigned_Type, which is done by this procedure. The call has no -- effect if the entity E is not a discrete or fixed-point type. procedure Freeze_And_Append (Ent : Entity_Id; 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 pre-analyzed). If the expression -- is not an entity or literal, its analysis may generate code which must -- not be executed. In that case we build a function body to hold that -- code. This wrapper function serves no other purpose (it used to be -- called to evaluate the default, but now the default is inlined at each -- point of call). procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id); -- Typ is a record or array type that is being frozen. This routine sets -- the default component alignment from the scope stack values if the -- alignment is otherwise not specified. procedure Check_Debug_Info_Needed (T : Entity_Id); -- As each entity is frozen, this routine is called to deal with the -- setting of Debug_Info_Needed for the entity. This flag is set if -- the entity comes from source, or if we are in Debug_Generated_Code -- mode or if the -gnatdV debug flag is set. However, it never sets -- the flag if Debug_Info_Off is set. This procedure also ensures that -- subsidiary entities have the flag set as required. 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. See 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 Chars (Renamed_Subp) = Name_Rotate_Left or else Chars (Renamed_Subp) = Name_Rotate_Right or else Chars (Renamed_Subp) = Name_Shift_Left or else Chars (Renamed_Subp) = Name_Shift_Right or else Chars (Renamed_Subp) = 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_Reference_To (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; -- 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_Reference_To (Formal, Loc), Actuals); Next_Formal (Formal); end loop; end if; -- If the renamed entity is an entry, inherit its profile. For other -- renamings as bodies, both profiles must be subtype conformant, so it -- is not necessary to replace the profile given in the declaration. -- However, default values that are aggregates are rewritten when -- partially analyzed, so we recover the original aggregate to insure -- that subsequent conformity checking works. Similarly, if the default -- expression was constant-folded, recover the original expression. Formal := First_Formal (Defining_Entity (Decl)); if Present (Formal) then O_Formal := First_Formal (Old_S); Param_Spec := First (Parameter_Specifications (Spec)); while Present (Formal) loop if Is_Entry (Old_S) then if Nkind (Parameter_Type (Param_Spec)) /= N_Access_Definition then Set_Etype (Formal, Etype (O_Formal)); Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal)); end if; elsif Nkind (Default_Value (O_Formal)) = N_Aggregate or else Nkind (Original_Node (Default_Value (O_Formal))) /= Nkind (Default_Value (O_Formal)) then Set_Expression (Param_Spec, New_Copy_Tree (Original_Node (Default_Value (O_Formal)))); end if; Next_Formal (Formal); Next_Formal (O_Formal); Next (Param_Spec); end loop; end if; -- If the renamed entity is a function, the generated body contains a -- return statement. Otherwise, build a procedure call. If the entity is -- an entry, subsequent analysis of the call will transform it into the -- proper entry or protected operation call. If the renamed entity is -- a character literal, return it directly. if Ekind (Old_S) = E_Function or else Ekind (Old_S) = E_Operator or else (Ekind (Old_S) = E_Subprogram_Type and then Etype (Old_S) /= Standard_Void_Type) then Call_Node := Make_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); Expr : Node_Id; Decl : constant Node_Id := Declaration_Node (E); Typ : constant Entity_Id := Etype (E); begin if Present (Addr) then Expr := Expression (Addr); if 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. Reset the flag now unless freeze actions were -- attached to it in the mean time. if No (Freeze_Node (E)) then Set_Has_Delayed_Freeze (E, False); end if; 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; Rewrite (Addr, Make_Null_Statement (Sloc (E))); elsif not Error_Posted (Expr) and then not Needs_Finalization (Typ) then Warn_Overlay (Expr, Typ, Name (Addr)); end if; end if; end Check_Address_Clause; ----------------------------- -- Check_Compile_Time_Size -- ----------------------------- procedure Check_Compile_Time_Size (T : Entity_Id) is procedure Set_Small_Size (T : Entity_Id; S : Uint); -- Sets the compile time known size (32 bits or less) in the Esize -- field, of T checking for a size clause that was given which attempts -- to give a smaller size, and also checking for an alignment clause. function Size_Known (T : Entity_Id) return Boolean; -- Recursive function that does all the work function Static_Discriminated_Components (T : Entity_Id) return Boolean; -- If T is a constrained subtype, its size is not known if any of its -- discriminant constraints is not static and it is not a null record. -- The test is conservative and doesn't check that the components are -- in fact constrained by non-static discriminant values. Could be made -- more precise ??? -------------------- -- Set_Small_Size -- -------------------- procedure Set_Small_Size (T : Entity_Id; S : Uint) is begin if S > 32 then return; -- 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 scalar types. This is true even for generic formal -- scalar 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_Scalar_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 less than 32 and may be packable). declare Esiz : Uint := Component_Size (T); Dim : Uint; begin Index := First_Index (T); while Present (Index) loop if Nkind (Index) = N_Range then Get_Index_Bounds (Index, Low, High); elsif Error_Posted (Scalar_Range (Etype (Index))) then return False; else Low := Type_Low_Bound (Etype (Index)); High := Type_High_Bound (Etype (Index)); end if; if not Compile_Time_Known_Value (Low) or else not Compile_Time_Known_Value (High) or else Etype (Index) = Any_Type then return False; else Dim := Expr_Value (High) - Expr_Value (Low) + 1; if Dim >= 0 then Esiz := Esiz * Dim; else Esiz := Uint_0; end if; end if; Next_Index (Index); end loop; Set_Small_Size (T, Esiz); return True; end; -- Access types always have known at compile time sizes elsif Is_Access_Type (T) then return True; -- 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. The -- reason we eliminate the discriminated case is that we don't -- know the way the back end lays out discriminated packed -- records. If Packed_Size_Known is True, then Packed_Size is -- the size in bits so far. Packed_Size_Known : Boolean := Is_Packed (T) and then not Has_Discriminants (T); Packed_Size : Uint := Uint_0; begin -- Test for variant part present if Has_Discriminants (T) and then Present (Parent (T)) and then Nkind (Parent (T)) = N_Full_Type_Declaration and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition and then not Null_Present (Type_Definition (Parent (T))) and then Present (Variant_Part (Component_List (Type_Definition (Parent (T))))) then -- If variant part is present, and type is unconstrained, -- then we must have defaulted discriminants, or a size -- clause must be present for the type, or else the size -- is definitely not known at compile time. if not Is_Constrained (T) and then No (Discriminant_Default_Value (First_Discriminant (T))) and then Unknown_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 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_Type (Etype (Comp))) then declare Ocomp : constant Entity_Id := Original_Record_Component (Comp); OCtyp : constant Entity_Id := Etype (Ocomp); Ind : Node_Id; Indtyp : Entity_Id; Lo, Hi : Node_Id; begin Ind := First_Index (OCtyp); while Present (Ind) loop Indtyp := Etype (Ind); if Is_Enumeration_Type (Indtyp) and then Has_Non_Standard_Rep (Indtyp) then Lo := Type_Low_Bound (Indtyp); Hi := Type_High_Bound (Indtyp); if Is_Entity_Name (Lo) and then Ekind (Entity (Lo)) = E_Discriminant then return False; elsif Is_Entity_Name (Hi) and then Ekind (Entity (Hi)) = E_Discriminant then return False; end if; end if; Next_Index (Ind); end loop; end; end if; -- Clearly size of record is not known if the size of one of -- the components is not known. if not Size_Known (Ctyp) then return False; end if; -- Accumulate packed size if possible if Packed_Size_Known then -- We can only deal with elementary types, since for -- non-elementary components, alignment enters into the -- picture, and we don't know enough to handle proper -- alignment in this context. Packed arrays count as -- elementary if the representation is a modular type. if Is_Elementary_Type (Ctyp) or else (Is_Array_Type (Ctyp) and then Present (Packed_Array_Type (Ctyp)) and then Is_Modular_Integer_Type (Packed_Array_Type (Ctyp))) then -- If RM_Size is known and static, then we can keep -- accumulating the packed size. if Known_Static_RM_Size (Ctyp) then -- A little glitch, to be removed sometime ??? -- gigi does not understand zero sizes yet. if RM_Size (Ctyp) = Uint_0 then Packed_Size_Known := False; -- Normal case where we can keep accumulating the -- packed array size. else Packed_Size := Packed_Size + RM_Size (Ctyp); end if; -- If we have a field whose RM_Size is not known then -- we can't figure out the packed size here. else Packed_Size_Known := False; end if; -- If we have a non-elementary type we can't figure out -- the packed array size (alignment issues). else Packed_Size_Known := False; end if; end if; 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_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_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 non trivial is something like -- subtype x1 is integer range -10 .. +10; -- subtype x2 is x1 range 0 .. V1; -- subtype x3 is x2 range V2 .. V3; -- subtype x4 is x3 range V4 .. V5; -- where Vn are variables. Here the base type is signed, but we still -- know that x4 is unsigned because of the lower bound of x2. -- The only way to deal with this is to look up the ancestor chain Ancestor := E; loop if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then return; end if; Lo_Bound := Type_Low_Bound (Ancestor); if Compile_Time_Known_Value (Lo_Bound) then if Expr_Rep_Value (Lo_Bound) >= 0 then Set_Is_Unsigned_Type (E, True); end if; return; else Ancestor := Ancestor_Subtype (Ancestor); -- If no ancestor had a static lower bound, go to base type if No (Ancestor) then -- Note: the reason we still check for a compile time known -- value for the base type is that at least in the case of -- generic formals, we can have bounds that fail this test, -- and there may be other cases in error situations. Btyp := Base_Type (E); if Btyp = Any_Type or else Etype (Btyp) = Any_Type then return; end if; Lo_Bound := Type_Low_Bound (Base_Type (E)); if Compile_Time_Known_Value (Lo_Bound) and then Expr_Rep_Value (Lo_Bound) >= 0 then Set_Is_Unsigned_Type (E, True); end if; return; end if; end if; end loop; end Check_Unsigned_Type; ------------------------- -- Is_Atomic_Aggregate -- ------------------------- function Is_Atomic_Aggregate (E : Entity_Id; Typ : Entity_Id) return Boolean is Loc : constant Source_Ptr := Sloc (E); New_N : Node_Id; Par : Node_Id; Temp : Entity_Id; begin Par := Parent (E); -- Array may be qualified, so find outer context if Nkind (Par) = N_Qualified_Expression then Par := Parent (Par); end if; if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement) and then Comes_From_Source (Par) then Temp := Make_Temporary (Loc, 'T', E); New_N := Make_Object_Declaration (Loc, Defining_Identifier => Temp, Object_Definition => New_Occurrence_Of (Typ, Loc), Expression => Relocate_Node (E)); Insert_Before (Par, New_N); Analyze (New_N); Set_Expression (Par, New_Occurrence_Of (Temp, Loc)); return True; else return False; end if; end Is_Atomic_Aggregate; ---------------- -- Freeze_All -- ---------------- -- Note: the easy coding for this procedure would be to just build a -- single list of freeze nodes and then insert them and analyze them -- all at once. This won't work, because the analysis of earlier freeze -- nodes may recursively freeze types which would otherwise appear later -- on in the freeze list. So we must analyze and expand the freeze nodes -- as they are generated. procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is E : Entity_Id; Decl : Node_Id; procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id); -- This is the internal recursive routine that does freezing of entities -- (but NOT the analysis of default expressions, which should not be -- recursive, we don't want to analyze those till we are sure that ALL -- the types are frozen). -------------------- -- Freeze_All_Ent -- -------------------- procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is E : Entity_Id; Flist : List_Id; Lastn : Node_Id; procedure Process_Flist; -- If freeze nodes are present, insert and analyze, and reset cursor -- for next insertion. ------------------- -- Process_Flist -- ------------------- procedure Process_Flist is begin if Is_Non_Empty_List (Flist) then Lastn := Next (After); Insert_List_After_And_Analyze (After, Flist); if Present (Lastn) then After := Prev (Lastn); else After := Last (List_Containing (After)); end if; end if; end Process_Flist; -- Start or processing for Freeze_All_Ent begin E := From; while Present (E) loop -- If the entity is an inner package which is not a package -- renaming, then its entities must be frozen at this point. Note -- that such entities do NOT get frozen at the end of the nested -- package itself (only library packages freeze). -- Same is true for task declarations, where anonymous records -- created for entry parameters must be frozen. if Ekind (E) = E_Package and then No (Renamed_Object (E)) and then not Is_Child_Unit (E) and then not Is_Frozen (E) then 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 (Parent (E)) = N_Task_Type_Declaration or else Nkind (Parent (E)) = N_Single_Task_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 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; 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_Subprogram_Body, N_Entry_Body, N_Package_Body, N_Protected_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; -- 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; elsif Ekind (E) in Task_Kind and then (Nkind (Parent (E)) = N_Task_Type_Declaration or else Nkind (Parent (E)) = N_Single_Task_Declaration) then declare Ent : Entity_Id; begin Ent := First_Entity (E); while Present (Ent) loop if Is_Entry (Ent) and then not Default_Expressions_Processed (Ent) then Process_Default_Expressions (Ent, After); end if; Next_Entity (Ent); end loop; end; -- We add finalization masters to access types whose designated types -- require finalization. This is normally done when freezing the -- type, but this misses recursive type definitions where the later -- members of the recursion introduce controlled components (such as -- can happen when incomplete types are involved), as well cases -- where a component type is private and the controlled full type -- occurs after the access type is frozen. Cases that don't need a -- finalization master are generic formal types (the actual type will -- have it) and types with Java and CIL conventions, since those are -- used for API bindings. (Are there any other cases that should be -- excluded here???) elsif Is_Access_Type (E) and then Comes_From_Source (E) and then not Is_Generic_Type (E) and then Needs_Finalization (Designated_Type (E)) then Build_Finalization_Master (E); end if; 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) is Freeze_Nodes : constant List_Id := Freeze_Entity (T, N); begin if Is_Non_Empty_List (Freeze_Nodes) then Insert_Actions (N, Freeze_Nodes); end if; end Freeze_Before; ------------------- -- Freeze_Entity -- ------------------- function Freeze_Entity (E : Entity_Id; N : Node_Id) return List_Id is Loc : constant Source_Ptr := Sloc (N); Test_E : Entity_Id := E; Comp : Entity_Id; F_Node : Node_Id; Indx : Node_Id; Formal : Entity_Id; Atype : Entity_Id; Result : List_Id := No_List; -- List of freezing actions, left at No_List if none Has_Default_Initialization : Boolean := False; -- This flag gets set to true for a variable with default initialization procedure Add_To_Result (N : Node_Id); -- N is a freezing action to be appended to the Result 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_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. function After_Last_Declaration return Boolean; -- If Loc is a freeze_entity that appears after the last declaration -- in the scope, inhibit error messages on late completion. procedure Freeze_Record_Type (Rec : Entity_Id); -- Freeze each component, handle some representation clauses, and freeze -- primitive operations if this is a tagged type. ------------------- -- Add_To_Result -- ------------------- procedure Add_To_Result (N : Node_Id) is begin if No (Result) then Result := New_List (N); else Append (N, Result); 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 (Attribute_Name (N) = Name_Access or else Attribute_Name (N) = Name_Unchecked_Access) and then Is_Entity_Name (Prefix (N)) and then Is_Type (Entity (Prefix (N))) and then Entity (Prefix (N)) = E then Error_Msg_N ("current instance must be a limited type", Prefix (N)); return Abandon; else return OK; end if; when others => return OK; end case; end Process; procedure Traverse is new Traverse_Proc (Process); -- 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_Modulus -- ------------------------------ procedure Check_Suspicious_Modulus (Utype : Entity_Id) is Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype)); begin 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 ("?2 '*'*^' may have been intended here", Modulus); end; end if; end; end if; end; end if; end Check_Suspicious_Modulus; ------------------------ -- Freeze_Record_Type -- ------------------------ procedure Freeze_Record_Type (Rec : Entity_Id) is Comp : Entity_Id; IR : Node_Id; ADC : Node_Id; Prev : Entity_Id; Junk : Boolean; pragma Warnings (Off, Junk); Unplaced_Component : Boolean := False; -- Set True if we find at least one component with no component -- clause (used to warn about useless Pack pragmas). Placed_Component : Boolean := False; -- Set True if we find at least one component with a component -- clause (used to warn about useless Bit_Order pragmas, and also -- to detect cases where Implicit_Packing may have an effect). All_Scalar_Components : Boolean := True; -- Set False if we encounter a component of a non-scalar type Scalar_Component_Total_RM_Size : Uint := Uint_0; Scalar_Component_Total_Esize : Uint := Uint_0; -- Accumulates total RM_Size values and total Esize values of all -- scalar components. Used for processing of Implicit_Packing. 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. --------------------- -- 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; -- Start of processing for Freeze_Record_Type begin -- Freeze components and embedded subtypes Comp := First_Entity (Rec); Prev := Empty; while Present (Comp) loop -- First handle the component case if Ekind (Comp) = E_Component or else Ekind (Comp) = E_Discriminant then declare CC : constant Node_Id := Component_Clause (Comp); begin -- Freezing a record type freezes the type of each of its -- components. However, if the type of the component is -- part of this record, we do not want or need a separate -- Freeze_Node. Note that Is_Itype is wrong because that's -- also set in private type cases. We also can't check for -- the Scope being exactly Rec because of private types and -- record extensions. if Is_Itype (Etype (Comp)) and then Is_Record_Type (Underlying_Type (Scope (Etype (Comp)))) then Undelay_Type (Etype (Comp)); end if; Freeze_And_Append (Etype (Comp), N, Result); -- Check for error of component clause given for variable -- sized type. We have to delay this test till this point, -- since the component type has to be frozen for us to know -- if it is variable length. We omit this test in a generic -- context, it will be applied at instantiation time. -- We also omit this test in CodePeer mode, since we do not -- have sufficient info on size and representation clauses. if Present (CC) then Placed_Component := True; if Inside_A_Generic then null; elsif CodePeer_Mode then null; elsif not Size_Known_At_Compile_Time (Underlying_Type (Etype (Comp))) then Error_Msg_N ("component clause not allowed for variable " & "length component", CC); end if; else Unplaced_Component := True; end if; -- Case of component requires byte alignment if Must_Be_On_Byte_Boundary (Etype (Comp)) then -- Set the enclosing record to also require byte align Set_Must_Be_On_Byte_Boundary (Rec); -- Check for component clause that is inconsistent with -- the required byte boundary alignment. if Present (CC) and then Normalized_First_Bit (Comp) mod System_Storage_Unit /= 0 then Error_Msg_N ("component & must be byte aligned", Component_Name (Component_Clause (Comp))); end if; end if; 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 not Is_Scalar_Type (Etype (Comp)) then All_Scalar_Components := False; else Scalar_Component_Total_RM_Size := Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp)); Scalar_Component_Total_Esize := Scalar_Component_Total_Esize + Esize (Etype (Comp)); 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 pretty bad kludge 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 Set_Next_Entity (Prev, Next_Entity (Comp)); else Set_First_Entity (Rec, Next_Entity (Comp)); end if; -- Insert in entity list of scope of base type (which -- must be an enclosing scope, because still unfrozen). Append_Entity (Comp, Scope (Base_Type (Comp))); end if; end; -- If the component is an access type with an allocator as default -- value, the designated type will be frozen by the corresponding -- expression in init_proc. In order to place the freeze node for -- the designated type before that for the current record type, -- freeze it now. -- Same process if the component is an array of access types, -- initialized with an aggregate. If the designated type is -- private, it cannot contain allocators, and it is premature -- to freeze the type, so we check for this as well. elsif Is_Access_Type (Etype (Comp)) and then Present (Parent (Comp)) and then Present (Expression (Parent (Comp))) then declare Alloc : constant Node_Id := Check_Allocator (Expression (Parent (Comp))); begin if Present (Alloc) then -- If component is pointer to a classwide type, freeze -- the specific type in the expression being allocated. -- The expression may be a subtype indication, in which -- case freeze the subtype mark. if Is_Class_Wide_Type (Designated_Type (Etype (Comp))) then if Is_Entity_Name (Expression (Alloc)) then Freeze_And_Append (Entity (Expression (Alloc)), 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)); elsif Is_Array_Type (Etype (Comp)) and then Is_Access_Type (Component_Type (Etype (Comp))) and then Present (Parent (Comp)) and then Nkind (Parent (Comp)) = N_Component_Declaration and then Present (Expression (Parent (Comp))) and then Nkind (Expression (Parent (Comp))) = N_Aggregate and then Is_Fully_Defined (Designated_Type (Component_Type (Etype (Comp)))) then Freeze_And_Append (Designated_Type (Component_Type (Etype (Comp))), N, Result); end if; Prev := Comp; Next_Entity (Comp); end loop; -- Deal with Bit_Order aspect specifying a non-default bit order if Reverse_Bit_Order (Rec) and then Base_Type (Rec) = Rec then if not Placed_Component then ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order); Error_Msg_N ("?Bit_Order specification has no effect", ADC); Error_Msg_N ("\?since no component clauses were specified", ADC); -- Here is where we do the processing for reversed bit order else Adjust_Record_For_Reverse_Bit_Order (Rec); 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; -- Set OK_To_Reorder_Components depending on debug flags if Is_Base_Type (Rec) and then Convention (Rec) = Convention_Ada then if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V) or else (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R) then Set_OK_To_Reorder_Components (Rec); end if; end if; -- Check for useless pragma Pack when all components placed. We only -- do this check for record types, not subtypes, since a subtype may -- have all its components placed, and it still makes perfectly good -- sense to pack other subtypes or the parent type. 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. -- Also, Check for controlled components and unchecked unions. -- Finally, enforce the restriction that access attributes with a -- current instance prefix can only apply to limited types. if Ekind (Rec) = E_Record_Type then if Present (Corresponding_Remote_Type (Rec)) then Freeze_And_Append (Corresponding_Remote_Type (Rec), N, Result); end if; 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; -- 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; 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; -- Generate warning for applying C or C++ convention to a record -- with discriminants. 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. if Has_Discriminants (E) and then not Is_Unchecked_Union (E) and then (Convention (E) = Convention_C or else Convention (E) = Convention_CPP) and then Comes_From_Source (E) and then not In_Instance and then not Has_Warnings_Off (E) and then not Has_Warnings_Off (Base_Type (E)) then declare Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention); A2 : Node_Id; begin if Present (Cprag) then A2 := Next (First (Pragma_Argument_Associations (Cprag))); if Convention (E) = Convention_C then Error_Msg_N ("?variant record has no direct equivalent in C", A2); else Error_Msg_N ("?variant record has no direct equivalent in C++", A2); end if; Error_Msg_NE ("\?use of convention for type& is dubious", A2, E); end if; end; 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 -- Must have size clause and all scalar components and then Has_Size_Clause (Rec) and then All_Scalar_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 can 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). and then RM_Size (Rec) < Scalar_Component_Total_Esize -- 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 RM_Size (Rec) >= Scalar_Component_Total_RM_Size -- Never do implicit packing in CodePeer or Alfa 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 Alfa_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; end Freeze_Record_Type; -- Start of processing for Freeze_Entity begin -- We are going to test for various reasons why this entity need not be -- frozen here, but in the case of an Itype that's defined within a -- record, that test actually applies to the record. if Is_Itype (E) and then Is_Record_Type (Scope (E)) then Test_E := Scope (E); elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E))) and then Is_Record_Type (Underlying_Type (Scope (E))) then Test_E := Underlying_Type (Scope (E)); end if; -- Do not freeze if already frozen since we only need one freeze node if Is_Frozen (E) then return No_List; -- It is improper to freeze an external entity within a generic because -- its freeze node will appear in a non-valid context. The entity will -- be frozen in the proper scope after the current generic is analyzed. elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then return No_List; -- 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 return No_List; -- Do not freeze a global entity within an inner scope created during -- expansion. A call to subprogram E within some internal procedure -- (a stream attribute for example) might require freezing E, but the -- freeze node must appear in the same declarative part as E itself. -- The two-pass elaboration mechanism in gigi guarantees that E will -- be frozen before the inner call is elaborated. We exclude constants -- from this test, because deferred constants may be frozen early, and -- must be diagnosed (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 return No_List; end if; end if; S := Scope (S); end loop; end; -- Similarly, an inlined instance body may make reference to global -- entities, but these references cannot be the proper freezing point -- for them, and 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 return No_List; end if; end; end if; -- Deal with delayed aspect specifications. The analysis of the aspect -- is required to be delayed to the freeze point, so we evaluate the -- pragma or attribute definition clause in the tree at this point. if Has_Delayed_Aspects (E) then declare Ritem : Node_Id; Aitem : Node_Id; begin -- Look for aspect specification entries for this entity 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) and then Scope (E) = Current_Scope then Aitem := Aspect_Rep_Item (Ritem); -- Skip if this is an aspect with no corresponding pragma -- or attribute definition node (such as Default_Value). if Present (Aitem) then Set_Parent (Aitem, Ritem); Analyze (Aitem); end if; end if; Next_Rep_Item (Ritem); end loop; end; 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 (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_Aggregate (Expression (Parent (E)), Etype (E)) then null; end if; -- For a subprogram, freeze all parameter types and also the return -- type (RM 13.14(14)). However skip this for internal subprograms. -- This is also the point where any extra formal parameters are -- created since we now know whether the subprogram will use a -- foreign convention. if Is_Subprogram (E) then if not Is_Internal (E) then declare F_Type : Entity_Id; 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)) then F_Type := Full_View (F_Type); Set_Etype (Formal, F_Type); end if; Freeze_And_Append (F_Type, N, Result); if Is_Private_Type (F_Type) and then Is_Private_Type (Base_Type (F_Type)) and then No (Full_View (Base_Type (F_Type))) and then not Is_Generic_Type (F_Type) and then not Is_Derived_Type (F_Type) then -- If the type of a formal is incomplete, subprogram -- is being frozen prematurely. Within an instance -- (but not within a wrapper package) this is an -- 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); return No_List; 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 if Is_Access_Type (F_Type) and then Esize (F_Type) > Ttypes.System_Address_Size then Error_Msg_N ("?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) and then VM_Target = No_VM then Error_Msg_N ("& is an 8-bit Ada Boolean?", Formal); Error_Msg_N ("\use appropriate corresponding type in C " & "(e.g. char)?", 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 ("?& 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 ("?subprogram pointer & should " & "have foreign convention!", Formal); Error_Msg_Sloc := Sloc (F_Type); Error_Msg_NE ("\?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 -- Exclude VM case, since both .NET and JVM can handle -- unconstrained arrays without a problem. and then VM_Target = No_VM then Error_Msg_Qual_Level := 1; -- If this is an inherited operation, place the -- warning on the derived type declaration, rather -- than on the original subprogram. if Nkind (Original_Node (Parent (E))) = N_Full_Type_Declaration then Warn_Node := Parent (E); if Formal = First_Formal (E) then Error_Msg_NE ("?in inherited operation&", Warn_Node, E); end if; else Warn_Node := Formal; end if; Error_Msg_NE ("?type of argument& is unconstrained array", Warn_Node, Formal); Error_Msg_NE ("?foreign caller must pass bounds explicitly", Warn_Node, Formal); Error_Msg_Qual_Level := 0; end if; if not From_With_Type (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. if Ekind (R_Type) = E_Incomplete_Type and then Present (Full_View (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 ("?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 VM_Target = No_VM 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?", N, E); Error_Msg_NE ("\use appropriate corresponding type in C " & "(e.g. char)?", 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 ("?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 ("?& should return a foreign " & "convention subprogram pointer", E); Error_Msg_Sloc := Sloc (R_Type); Error_Msg_NE ("\?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) -- Exclude VM case, since both .NET and JVM can handle -- return of unconstrained arrays without a problem. and then VM_Target = No_VM -- 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 ("?foreign convention function& should not " & "return unconstrained array!", E); end if; end if; end; end if; -- Must freeze its parent first if it is a derived subprogram if Present (Alias (E)) then Freeze_And_Append (Alias (E), 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; -- 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); end if; -- Special processing for objects created by object declaration if Nkind (Declaration_Node (E)) = N_Object_Declaration then -- 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 (Etype (E)) and then Comes_From_Source (Parent (E)) and then not (Is_Imported (E) and then Is_CPP_Class (Etype (E))) then Error_Msg_N ("type of object cannot be abstract", Object_Definition (Parent (E))); if Is_CPP_Class (Etype (E)) then Error_Msg_NE ("\} may need a cpp_constructor", Object_Definition (Parent (E)), Etype (E)); 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 Check_Address_Clause (E); -- 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 (Etype (E)) and then not No_Initialization (Declaration_Node (E)) and then not Is_Value_Type (Etype (E)) and then not Initialization_Suppressed (Etype (E))) or else (Needs_Simple_Initialization (Etype (E)) 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_Static_Expression (Expression (Decl)) or else Nkind (Expression (Decl)) = N_Null))) then Error_Msg_NE ("Thread_Local_Storage variable& is " & "improperly initialized", Decl, E); Error_Msg_NE ("\only allowed initialization is explicit " & "NULL or static expression", Decl, E); 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 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, 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 (Etype (E)) and then not Is_Character_Type (Etype (E)) and then not Is_Boolean_Type (Etype (E)) and then Esize (Etype (E)) < 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; end if; -- Check that a constant which has a pragma Volatile[_Components] -- or Atomic[_Components] also has a pragma Import (RM C.6(13)). -- Note: Atomic[_Components] also sets Volatile[_Components] if Ekind (E) = E_Constant and then (Has_Volatile_Components (E) or else Is_Volatile (E)) and then not Is_Imported (E) then -- Make sure we actually have a pragma, and have not merely -- inherited the indication from elsewhere (e.g. an address -- clause, which is not good enough in RM terms!) if Has_Rep_Pragma (E, Name_Atomic) or else Has_Rep_Pragma (E, Name_Atomic_Components) then Error_Msg_N ("stand alone atomic constant must be " & "imported (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 (E) = E_Variable or else Ekind (E) = E_Constant or else Ekind (E) = E_Loop_Parameter or else Is_Formal (E) then Layout_Object (E); end if; end if; -- Case of a type or subtype being frozen else -- 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. if Present (Scope (E)) and then Is_Generic_Unit (Scope (E)) and then not Has_Predicates (E) then Check_Compile_Time_Size (E); return No_List; end if; -- Deal with special cases of freezing for subtype if E /= Base_Type (E) then -- Before we do anything else, a specialized test for the case of -- a size given for an array where the array needs to be packed, -- but was not so the size cannot be honored. This would of course -- be caught by the backend, and indeed we don't catch all cases. -- The point is that we can give a better error message in those -- cases that we do catch with the circuitry here. Also if pragma -- Implicit_Packing is set, this is where the packing occurs. -- The reason we do this so early is that the processing in the -- automatic packing case affects the layout of the base type, so -- it must be done before we freeze the base type. if Is_Array_Type (E) then declare Lo, Hi : Node_Id; Ctyp : constant Entity_Id := Component_Type (E); 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). if Present (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 Number_Dimensions (E) = 1 and then not Has_Component_Size_Clause (E) and then Known_Static_RM_Size (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 Alfa_Mode) then Get_Index_Bounds (First_Index (E), Lo, Hi); if Compile_Time_Known_Value (Lo) and then Compile_Time_Known_Value (Hi) and then Known_Static_RM_Size (Ctyp) and then RM_Size (Ctyp) < 64 then declare Lov : constant Uint := Expr_Value (Lo); Hiv : constant Uint := Expr_Value (Hi); Len : constant Uint := UI_Max (Uint_0, Hiv - Lov + 1); Rsiz : constant Uint := RM_Size (Ctyp); SZ : constant Node_Id := Size_Clause (E); Btyp : constant Entity_Id := Base_Type (E); -- 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 same as the RM_Size). Furthermore, the -- component type size must be an odd size (not a -- multiple of storage unit). If the component RM size -- is an exact number of storage units that is a power -- of two, the array is not packed and has a standard -- representation. begin if RM_Size (E) = Len * Rsiz and then Rsiz mod System_Storage_Unit /= 0 then -- For implicit packing mode, just set the -- component size silently. if Implicit_Packing then Set_Component_Size (Btyp, Rsiz); Set_Is_Bit_Packed_Array (Btyp); Set_Is_Packed (Btyp); Set_Has_Non_Standard_Rep (Btyp); -- 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; elsif RM_Size (E) = Len * Rsiz and then Implicit_Packing and then (Rsiz / System_Storage_Unit = 1 or else Rsiz / System_Storage_Unit = 2 or else Rsiz / System_Storage_Unit = 4) then -- Not a packed array, but indicate the desired -- component size, for the back-end. Set_Component_Size (Btyp, Rsiz); end if; end; end if; end if; end; end if; -- 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; -- 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); end if; -- For array type, freeze index types and component type first -- before freezing the array (RM 13.14(15)). if Is_Array_Type (E) then declare FS : constant Entity_Id := First_Subtype (E); Ctyp : constant Entity_Id := Component_Type (E); 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 (E); 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 (E) = E_Array_Type then -- Propagate flags for component type if Is_Controlled (Component_Type (E)) or else Has_Controlled_Component (Ctyp) then Set_Has_Controlled_Component (E); end if; if Has_Unchecked_Union (Component_Type (E)) then Set_Has_Unchecked_Union (E); end if; -- If packing was requested or if the component size was set -- explicitly, then see if bit packing is required. This -- processing is only done for base types, since all the -- representation aspects involved are type-related. This -- is not just an optimization, if we start processing the -- subtypes, they 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 (E) or else Has_Pragma_Pack (E)) and then Known_Static_RM_Size (Ctyp) and then not Has_Component_Size_Clause (E) then Csiz := UI_Max (RM_Size (Ctyp), 1); elsif Known_Component_Size (E) then Csiz := Component_Size (E); elsif not Known_Static_Esize (Ctyp) then Csiz := Uint_0; else Esiz := Esize (Ctyp); -- We can set the component size if it is less than -- 16, rounding it up to the next storage unit size. if Esiz <= 8 then Csiz := Uint_8; elsif Esiz <= 16 then Csiz := Uint_16; else Csiz := Uint_0; end if; -- Set component size up to match alignment if it -- would otherwise be less than the alignment. This -- deals with cases of types whose alignment exceeds -- their size (padded types). if Csiz /= 0 then declare A : constant Uint := Alignment_In_Bits (Ctyp); begin if Csiz < A then Csiz := A; end if; end; end if; end if; -- Case of component size that may result in packing if 1 <= Csiz and then Csiz <= 64 then declare Ent : constant Entity_Id := First_Subtype (E); 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 ("?pragma Pack for& ignored!", Pack_Pragma, Ent); Error_Msg_N ("\?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 (E, 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 (E) 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; -- Actual packing is not needed for 8, 16, 32, 64. -- Also not needed for 24 if alignment is 1. if Csiz = 8 or else Csiz = 16 or else Csiz = 32 or else Csiz = 64 or else (Csiz = 24 and then Alignment (Ctyp) = 1) then -- Here the array was requested to be packed, -- but the packing request had no effect, so -- Is_Packed is reset. -- Note: semantically this means that we lose -- track of the fact that a derived type -- inherited a pragma Pack that was non- -- effective, but that seems fine. -- We regard a Pack pragma as a request to set -- a representation characteristic, and this -- request may be ignored. Set_Is_Packed (Base_Type (E), False); Set_Is_Bit_Packed_Array (Base_Type (E), False); if Known_Static_Esize (Component_Type (E)) and then Esize (Component_Type (E)) = Csiz then Set_Has_Non_Standard_Rep (Base_Type (E), False); end if; -- In all other cases, packing is indeed needed else Set_Has_Non_Standard_Rep (Base_Type (E), True); Set_Is_Bit_Packed_Array (Base_Type (E), True); Set_Is_Packed (Base_Type (E), True); end if; end; end if; end; -- Check for Atomic_Components or Aliased with unsuitable -- packing or explicit component size clause given. if (Has_Atomic_Components (E) or else Has_Aliased_Components (E)) and then (Has_Component_Size_Clause (E) or else Is_Packed (E)) then Alias_Atomic_Check : declare procedure Complain_CS (T : String); -- Outputs error messages for incorrect CS clause or -- pragma Pack for aliased or atomic components (T is -- "aliased" or "atomic"); ----------------- -- Complain_CS -- ----------------- procedure Complain_CS (T : String) is begin if Has_Component_Size_Clause (E) then Clause := Get_Attribute_Definition_Clause (FS, Attribute_Component_Size); if Known_Static_Esize (Ctyp) then 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 ("component size cannot be given for " & T & " components", Clause); end if; else Error_Msg_N ("cannot pack " & T & " components", Get_Rep_Pragma (FS, Name_Pack)); end if; return; 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 the 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 (E) and then Component_Size (E) = Esize (Ctyp))) then null; elsif Has_Aliased_Components (E) or else Is_Aliased (Ctyp) then Complain_CS ("aliased"); elsif Has_Atomic_Components (E) or else Is_Atomic (Ctyp) then Complain_CS ("atomic"); end if; end Alias_Atomic_Check; 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, E); if Has_Component_Size_Clause (E) 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 (E) then Error_Msg_Sloc := Sloc (Get_Rep_Pragma (FS, Name_Pack)); Error_Msg_N ("\because of pragma Pack#?", Clause); end if; end if; -- Processing that is done only for subtypes else -- Acquire alignment from base type if Unknown_Alignment (E) then Set_Alignment (E, Alignment (Base_Type (E))); Adjust_Esize_Alignment (E); end if; end if; -- For bit-packed arrays, check the size if Is_Bit_Packed_Array (E) and then Known_RM_Size (E) then declare SizC : constant Node_Id := Size_Clause (E); Discard : Boolean; pragma Warnings (Off, Discard); 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), E, RM_Size (E), Discard); else Check_Size (E, E, RM_Size (E), Discard); end if; end; 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 (E)); Set_Is_Packed (Base_Type (E)); end if; Set_Component_Alignment_If_Not_Set (E); -- If the array is packed, we must create the packed array -- type to be used to actually implement the type. This is -- only needed for real array types (not for string literal -- types, since they are present only for the front end). if Is_Packed (E) and then Ekind (E) /= E_String_Literal_Subtype then Create_Packed_Array_Type (E); Freeze_And_Append (Packed_Array_Type (E), N, Result); -- 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_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 (E) and then (No (Ancestor_Subtype (E)) or else not Has_Size_Clause (Ancestor_Subtype (E))) then Set_Esize (E, Esize (Packed_Array_Type (E))); Set_RM_Size (E, RM_Size (Packed_Array_Type (E))); end if; if not Has_Alignment_Clause (E) then Set_Alignment (E, Alignment (Packed_Array_Type (E))); end if; end if; -- For non-packed arrays set the alignment of the array to the -- alignment of the component type if it is unknown. Skip this -- in atomic case (atomic arrays may need larger alignments). if not Is_Packed (E) and then Unknown_Alignment (E) and then Known_Alignment (Ctyp) and then Known_Static_Component_Size (E) and then Known_Static_Esize (Ctyp) and then Esize (Ctyp) = Component_Size (E) and then not Is_Atomic (E) then Set_Alignment (E, Alignment (Component_Type (E))); end if; end; -- For a class-wide type, the corresponding specific type is -- frozen as well (RM 13.14(15)) elsif Is_Class_Wide_Type (E) then Freeze_And_Append (Root_Type (E), 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); return Result; end if; -- If the Class_Wide_Type is an Itype (when type is the anonymous -- parent of a derived type) and it is a library-level entity, -- generate an itype reference for it. Otherwise, its first -- explicit reference may be in an inner scope, which will be -- rejected by the back-end. if Is_Itype (E) and then Is_Compilation_Unit (Scope (E)) then declare Ref : constant Node_Id := Make_Itype_Reference (Loc); begin Set_Itype (Ref, E); Add_To_Result (Ref); end; 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; -- For a record (sub)type, freeze all the component types (RM -- 13.14(15). We test for E_Record_(sub)Type here, rather than using -- Is_Record_Type, because we don't want to attempt the freeze for -- the case of a private type with record extension (we will do that -- later when the full type is frozen). elsif Ekind (E) = E_Record_Type or else Ekind (E) = E_Record_Subtype then Freeze_Record_Type (E); -- For a concurrent type, freeze corresponding record type. This -- does not correspond to any specific rule in the RM, but the -- record type is essentially part of the concurrent type. -- Freeze as well all local entities. This includes record types -- created for entry parameter blocks, and whatever local entities -- may appear in the private part. elsif Is_Concurrent_Type (E) then if Present (Corresponding_Record_Type (E)) then Freeze_And_Append (Corresponding_Record_Type (E), 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 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; Next_Entity (Comp); end loop; -- Private types are required to point to the same freeze node as -- their corresponding full views. The freeze node itself has to -- point to the partial view of the entity (because from the partial -- view, we can retrieve the full view, but not the reverse). -- However, in order to freeze correctly, we need to freeze the full -- view. If we are freezing at the end of a scope (or within the -- scope of the private type), the partial and full views will have -- been swapped, the full view appears first in the entity chain and -- the swapping mechanism ensures that the pointers are properly set -- (on scope exit). -- If we encounter the partial view before the full view (e.g. when -- freezing from another scope), we freeze the full view, and then -- set the pointers appropriately since we cannot rely on swapping to -- fix things up (subtypes in an outer scope might not get swapped). elsif Is_Incomplete_Or_Private_Type (E) and then not Is_Generic_Type (E) then -- 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); return Result; -- 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); Check_Debug_Info_Needed (E); -- Otherwise freeze full view and patch the pointers so that -- the freeze node will elaborate both views in the back-end. else declare Full : constant Entity_Id := Full_View (E); begin if Is_Private_Type (Full) and then Present (Underlying_Full_View (Full)) then Freeze_And_Append (Underlying_Full_View (Full), N, Result); end if; Freeze_And_Append (Full, N, Result); if Has_Delayed_Freeze (E) then F_Node := Freeze_Node (Full); if Present (F_Node) then Set_Freeze_Node (E, F_Node); Set_Entity (F_Node, E); else -- {Incomplete,Private}_Subtypes with Full_Views -- constrained by discriminants. Set_Has_Delayed_Freeze (E, False); Set_Freeze_Node (E, Empty); end if; end if; end; Check_Debug_Info_Needed (E); end if; -- AI-117 requires that the convention of a partial view be the -- same as the convention of the full view. Note that this is a -- recognized breach of privacy, but it's essential for logical -- consistency of representation, and the lack of a rule in -- RM95 was an oversight. Set_Convention (E, Convention (Full_View (E))); Set_Size_Known_At_Compile_Time (E, Size_Known_At_Compile_Time (Full_View (E))); -- Size information is copied from the full view to the -- incomplete or private view for consistency. -- We skip this is the full view is not a type. This is very -- strange of course, and can only happen as a result of -- certain illegalities, such as a premature attempt to derive -- from an incomplete type. if Is_Type (Full_View (E)) then Set_Size_Info (E, Full_View (E)); Set_RM_Size (E, RM_Size (Full_View (E))); end if; return Result; -- Case of no full view present. If entity is derived or subtype, -- it is safe to freeze, correctness depends on the frozen status -- of parent. Otherwise it is either premature usage, or a Taft -- amendment type, so diagnosis is at the point of use and the -- type might be frozen later. elsif E /= Base_Type (E) or else Is_Derived_Type (E) then null; else Set_Is_Frozen (E, False); return No_List; end if; -- For access subprogram, freeze types of all formals, the return -- type was already frozen, since it is the Etype of the function. -- 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))) and then not Is_Value_Type (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 return Result; end if; -- Some special processing for non-generic types to complete -- representation details not known till the freeze point. if Is_Fixed_Point_Type (E) then Freeze_Fixed_Point_Type (E); -- Some error checks required for ordinary fixed-point type. Defer -- these till the freeze-point since we need the small and range -- values. We only do these checks for base types if Is_Ordinary_Fixed_Point_Type (E) and then 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; elsif Is_Access_Type (E) 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. 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)) 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_Immutably_Limited_Type (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 (Op_Name = Name_Allocate or else Op_Name = Name_Deallocate or else Op_Name = 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_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); -- If no address clause and not intrinsic, then for imported -- subprogram in main unit, generate descriptor if we are in -- Propagate_Exceptions mode. -- This is very odd code, it makes a null result, why ??? elsif Propagate_Exceptions and then Is_Imported (E) and then not Is_Intrinsic_Subprogram (E) and then Convention (E) /= Convention_Stubbed then if Result = No_List then Result := Empty_List; end if; end if; end if; return Result; end Freeze_Entity; ----------------------------- -- Freeze_Enumeration_Type -- ----------------------------- procedure Freeze_Enumeration_Type (Typ : Entity_Id) is begin -- 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. 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 Has_Size_Clause (Typ) and then not Has_Size_Clause (Base_Type (Typ)) and then Esize (Typ) < Standard_Integer_Size then Init_Esize (Typ, Standard_Integer_Size); Set_Alignment (Typ, Alignment (Standard_Integer)); 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) 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 In_Spec_Exp : constant Boolean := In_Spec_Expression; Typ : Entity_Id; Nam : Entity_Id; Desig_Typ : Entity_Id; P : Node_Id; Parent_P : Node_Id; Freeze_Outside : Boolean := False; -- This flag is set true if the entity must be frozen outside the -- current subprogram. This happens in the case of expander generated -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do -- not freeze all entities like other bodies, but which nevertheless -- may reference entities that have to be frozen before the body and -- obviously cannot be frozen inside the body. function In_Exp_Body (N : Node_Id) return Boolean; -- Given an N_Handled_Sequence_Of_Statements node N, determines whether -- it is the handled statement sequence of an expander-generated -- subprogram (init proc, stream subprogram, or renaming as body). -- If so, this is not a freezing context. ----------------- -- In_Exp_Body -- ----------------- function In_Exp_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)); 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 (Original_Node (P)) = N_Subprogram_Renaming_Declaration) then return True; else return False; end if; end if; end In_Exp_Body; -- Start of processing for Freeze_Expression begin -- Immediate return if freezing is inhibited. This flag is set by the -- analyzer to stop freezing on generated expressions that would cause -- freezing if they were in the source program, but which are not -- supposed to freeze, since they are created. if Must_Not_Freeze (N) then return; end if; -- If expression is non-static, then it does not freeze in a default -- expression, see section "Handling of Default Expressions" in the -- spec of package Sem for further details. Note that we have to make -- sure that we actually have a real expression (if we have a subtype -- indication, we can't test Is_Static_Expression!) 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_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_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); 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 Desig_Typ := Designated_Type (Component_Type (Etype (N))); end if; when N_Selected_Component | N_Indexed_Component | N_Slice => if Is_Access_Type (Etype (Prefix (N))) then Desig_Typ := Designated_Type (Etype (Prefix (N))); end if; when 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; -- Loop for looking at the right place to insert the freeze nodes, -- exiting from the loop when it is appropriate to insert the freeze -- node before the current node P. -- Also checks some special exceptions to the freezing rules. These -- cases result in a direct return, bypassing the freeze action. P := N; loop Parent_P := Parent (P); -- If we don't have a parent, then we are not in a well-formed tree. -- This is an unusual case, but there are some legitimate situations -- in which this occurs, notably when the expressions in the range of -- a type declaration are resolved. We simply ignore the freeze -- request in this case. Is this right ??? if No (Parent_P) then return; end if; -- See if we have got to an appropriate point in the tree case Nkind (Parent_P) is -- A special test for the exception of (RM 13.14(8)) for the case -- of per-object expressions (RM 3.8(18)) occurring in component -- definition or a discrete subtype definition. Note that we test -- for a component declaration which includes both cases we are -- interested in, and furthermore the tree does not have explicit -- nodes for either of these two constructs. when N_Component_Declaration => -- The case we want to test for here is an identifier that is -- a per-object expression, this is either a discriminant that -- appears in a context other than the component declaration -- or it is a reference to the type of the enclosing construct. -- For either of these cases, we skip the freezing if not In_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 (N) = N_Identifier or Nkind (N) = N_Character_Literal) and then Is_Enumeration_Type (Etype (N)) then -- If enumeration literal appears directly as the choice, -- do not freeze (this is the normal non-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_Exp_Body (Parent_P) then -- However, we *do* want to freeze at this point if we have -- an entity to freeze, and that entity is declared *inside* -- the body of the expander generated procedure. This case -- is recognized by the scope of the type, which is either -- the spec for some enclosing body, or (in the case of -- init_procs, for which there are no separate specs) the -- current scope. declare Subp : constant Node_Id := Parent (Parent_P); Cspc : Entity_Id; begin if Nkind (Subp) = N_Subprogram_Body then Cspc := Corresponding_Spec (Subp); if (Present (Typ) and then Scope (Typ) = Cspc) or else (Present (Nam) and then Scope (Nam) = Cspc) then exit; elsif Present (Typ) and then Scope (Typ) = Current_Scope and then Current_Scope = Defining_Entity (Subp) then exit; end if; end if; end; -- If not that exception to the exception, then this is -- where we delay the freeze till outside the body. Parent_P := Parent (Parent_P); Freeze_Outside := True; -- Here if normal case where we are in handled statement -- sequence and want to do the insertion right there. else exit; end if; -- If parent is a body or a spec or a block, then the current node -- is a statement or declaration and we can insert the freeze node -- before it. when N_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); -- Note: The N_Loop_Statement is a special case. A type that -- appears in the source can never be frozen in a loop (this -- occurs only because of a loop expanded by the expander), so we -- keep on going. Otherwise we terminate the search. Same is true -- of any entity which comes from source. (if they have predefined -- type, that type does not appear to come from source, but the -- entity should not be frozen here). when N_Loop_Statement => exit when not Comes_From_Source (Etype (N)) and then (No (Nam) or else not Comes_From_Source (Nam)); -- For all other cases, keep looking at parents when others => null; end case; -- We fall through the case if we did not yet find the proper -- place in the free for inserting the freeze node, so climb! P := Parent_P; end loop; -- If the expression appears in a record or an initialization procedure, -- the freeze nodes are collected and attached to the current scope, to -- be inserted and analyzed on exit from the scope, to insure that -- generated entities appear in the correct scope. If the expression is -- a default for a discriminant specification, the scope is still void. -- The expression can also appear in the discriminant part of a private -- or concurrent type. -- If the expression appears in a constrained subcomponent of an -- enclosing record declaration, the freeze nodes must be attached to -- the outer record type so they can eventually be placed in the -- enclosing declaration list. -- The other case requiring this special handling is if we are in a -- default expression, since in that case we are about to freeze a -- static type, and the freeze scope needs to be the outer scope, not -- the scope of the subprogram with the default parameter. -- For default expressions 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, which is above the current -- scope in the scope stack. -- 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)) 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_Fixed_Point_Type -- ----------------------------- -- Certain fixed-point types and subtypes, including implicit base types -- and declared first subtypes, have not yet set up a range. This is -- because the range cannot be set until the Small and Size values are -- known, and these are not known till the type is frozen. -- To signal this case, Scalar_Range contains an unanalyzed syntactic range -- whose bounds are unanalyzed real literals. This routine will recognize -- this case, and transform this range node into a properly typed range -- with properly analyzed and resolved values. procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is Rng : constant Node_Id := Scalar_Range (Typ); Lo : constant Node_Id := Low_Bound (Rng); Hi : constant Node_Id := High_Bound (Rng); Btyp : constant Entity_Id := Base_Type (Typ); Brng : constant Node_Id := Scalar_Range (Btyp); BLo : constant Node_Id := Low_Bound (Brng); BHi : constant Node_Id := High_Bound (Brng); Small : constant Ureal := Small_Value (Typ); Loval : Ureal; Hival : Ureal; Atype : Entity_Id; Actual_Size : Nat; function Fsize (Lov, Hiv : Ureal) return Nat; -- Returns size of type with given bounds. Also leaves these -- bounds set as the current bounds of the Typ. ----------- -- Fsize -- ----------- function Fsize (Lov, Hiv : Ureal) return Nat is begin Set_Realval (Lo, Lov); Set_Realval (Hi, Hiv); return Minimum_Size (Typ); end Fsize; -- Start of processing for Freeze_Fixed_Point_Type begin -- If Esize of a subtype has not previously been set, set it now if Unknown_Esize (Typ) then Atype := Ancestor_Subtype (Typ); if Present (Atype) then Set_Esize (Typ, Esize (Atype)); else Set_Esize (Typ, Esize (Base_Type (Typ))); end if; end if; -- Immediate return if the range is already analyzed. This means that -- the range is already set, and does not need to be computed by this -- routine. if Analyzed (Rng) then return; end if; -- Immediate return if either of the bounds raises Constraint_Error if Raises_Constraint_Error (Lo) or else Raises_Constraint_Error (Hi) then return; end if; Loval := Realval (Lo); Hival := Realval (Hi); -- Ordinary fixed-point case if Is_Ordinary_Fixed_Point_Type (Typ) then -- For the ordinary fixed-point case, we are allowed to fudge the -- end-points up or down by small. Generally we prefer to fudge up, -- i.e. widen the bounds for non-model numbers so that the end points -- are included. However there are cases in which this cannot be -- done, and indeed cases in which we may need to narrow the bounds. -- The following circuit makes the decision. -- Note: our terminology here is that Incl_EP means that the bounds -- are widened by Small if necessary to include the end points, and -- Excl_EP means that the bounds are narrowed by Small to exclude the -- end-points if this reduces the size. -- Note that in the Incl case, all we care about is including the -- end-points. In the Excl case, we want to narrow the bounds as -- much as permitted by the RM, to give the smallest possible size. Fudge : declare Loval_Incl_EP : Ureal; Hival_Incl_EP : Ureal; Loval_Excl_EP : Ureal; Hival_Excl_EP : Ureal; Size_Incl_EP : Nat; Size_Excl_EP : Nat; Model_Num : Ureal; First_Subt : Entity_Id; Actual_Lo : Ureal; Actual_Hi : Ureal; begin -- First step. Base types are required to be symmetrical. Right -- now, the base type range is a copy of the first subtype range. -- This will be corrected before we are done, but right away we -- need to deal with the case where both bounds are non-negative. -- In this case, we set the low bound to the negative of the high -- bound, to make sure that the size is computed to include the -- required sign. Note that we do not need to worry about the -- case of both bounds negative, because the sign will be dealt -- with anyway. Furthermore we can't just go making such a bound -- symmetrical, since in a twos-complement system, there is an -- extra negative value which could not be 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; 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_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 Retype : Entity_Id; F : Entity_Id; begin -- Subprogram may not have an address clause unless it is imported if Present (Address_Clause (E)) then if not Is_Imported (E) then Error_Msg_N ("address clause can only be given " & "for imported subprogram", Name (Address_Clause (E))); end if; end if; -- Reset the Pure indication on an imported subprogram unless an -- explicit Pure_Function pragma was present. We do this because -- otherwise it is an insidious error to call a non-pure function from -- pure unit and have calls mysteriously optimized away. What happens -- here is that the Import can bypass the normal check to ensure that -- pure units call only pure subprograms. if Is_Imported (E) and then Is_Pure (E) and then not Has_Pragma_Pure_Function (E) then Set_Is_Pure (E, False); end if; -- For non-foreign convention subprograms, this is where we create -- the extra formals (for accessibility level and constrained bit -- information). We delay this till the freeze point precisely so -- that we know the convention! if not Has_Foreign_Convention (E) then Create_Extra_Formals (E); Set_Mechanisms (E); -- If this is convention Ada and a Valued_Procedure, that's odd if Ekind (E) = E_Procedure and then Is_Valued_Procedure (E) and then Convention (E) = Convention_Ada and then Warn_On_Export_Import then Error_Msg_N ("?Valued_Procedure has no effect for convention Ada", E); Set_Is_Valued_Procedure (E, False); end if; -- Case of foreign convention else Set_Mechanisms (E); -- For foreign conventions, warn about return of an -- unconstrained array. -- Note: we *do* allow a return by descriptor for the VMS case, -- though here there is probably more to be done ??? if Ekind (E) = E_Function then Retype := Underlying_Type (Etype (E)); -- If no return type, probably some other error, e.g. a -- missing full declaration, so ignore. if No (Retype) then null; -- If the return type is generic, we have emitted a warning -- earlier on, and there is nothing else to check here. Specific -- instantiations may lead to erroneous behavior. elsif Is_Generic_Type (Etype (E)) then null; -- Display warning if returning unconstrained array elsif Is_Array_Type (Retype) and then not Is_Constrained (Retype) -- Exclude cases where descriptor mechanism is set, since the -- VMS descriptor mechanisms allow such unconstrained returns. and then Mechanism (E) not in Descriptor_Codes -- Check appropriate warning is enabled (should we check for -- Warnings (Off) on specific entities here, probably so???) and then Warn_On_Export_Import -- Exclude the VM case, since return of unconstrained arrays -- is properly handled in both the JVM and .NET cases. and then VM_Target = No_VM then Error_Msg_N ("?foreign convention function& should not return " & "unconstrained array", E); return; end if; end if; -- If any of the formals for an exported foreign convention -- subprogram have defaults, then emit an appropriate warning since -- this is odd (default cannot be used from non-Ada code) if Is_Exported (E) then F := First_Formal (E); while Present (F) loop if Warn_On_Export_Import and then Present (Default_Value (F)) then Error_Msg_N ("?parameter cannot be defaulted in non-Ada call", Default_Value (F)); end if; Next_Formal (F); end loop; end if; end if; -- For VMS, descriptor mechanisms for parameters are allowed only for -- imported/exported subprograms. Moreover, the NCA descriptor is not -- allowed for parameters of exported subprograms. if OpenVMS_On_Target then if Is_Exported (E) then F := First_Formal (E); while Present (F) loop if Mechanism (F) = By_Descriptor_NCA then Error_Msg_N ("'N'C'A' descriptor for parameter not permitted", F); Error_Msg_N ("\can only be used for imported subprogram", F); end if; Next_Formal (F); end loop; elsif not Is_Imported (E) then F := First_Formal (E); while Present (F) loop if Mechanism (F) in Descriptor_Codes then Error_Msg_N ("descriptor mechanism for parameter not permitted", F); Error_Msg_N ("\can only be used for imported/exported subprogram", F); end if; Next_Formal (F); end loop; end if; end if; -- Pragma Inline_Always is disallowed for dispatching subprograms -- because the address of such subprograms is saved in the dispatch -- table to support dispatching calls, and dispatching calls cannot -- be inlined. This is consistent with the restriction against using -- 'Access or 'Address on an Inline_Always subprogram. if Is_Dispatching_Operation (E) and then 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; 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 (Dcopy) = N_Expanded_Name or else Nkind (Dcopy) = N_Integer_Literal or else (Nkind (Dcopy) = N_Real_Literal and then not Vax_Float (Etype (Dcopy))) or else Nkind (Dcopy) = N_Character_Literal or else Nkind (Dcopy) = N_String_Literal or else Known_Null (Dcopy) or else (Nkind (Dcopy) = N_Attribute_Reference and then Attribute_Name (Dcopy) = Name_Null_Parameter) then -- If there is no default function, we must still do a full -- analyze call on the default value, to ensure that all error -- checks are performed, e.g. those associated with static -- evaluation. Note: this branch will always be taken if the -- analyzer is turned off (but we still need the error checks). -- Note: the setting of parent here is to meet the requirement -- that we can only analyze the expression while attached to -- the tree. Really the requirement is that the parent chain -- be set, we don't actually need to be in the tree. Set_Parent (Dcopy, Declaration_Node (Formal)); Analyze (Dcopy); -- Default expressions are resolved with their own type if the -- context is generic, to avoid anomalies with private types. if Ekind (Scope (E)) = E_Generic_Package then Resolve (Dcopy); else Resolve (Dcopy, Etype (Formal)); end if; -- If that resolved expression will raise constraint error, -- then flag the default value as raising constraint error. -- This allows a proper error message on the calls. if Raises_Constraint_Error (Dcopy) then Set_Raises_Constraint_Error (Default_Value (Formal)); end if; -- If the default is a parameterless call, we use the name of -- the called function directly, and there is no body to build. elsif Nkind (Dcopy) = N_Function_Call and then No (Parameter_Associations (Dcopy)) then null; -- Else construct and analyze the body of a wrapper procedure -- that contains an object declaration to hold the expression. -- Given that this is done only to complete the analysis, it -- simpler to build a procedure than a function which might -- involve secondary stack expansion. else Dnam := Make_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; ------------------ -- Undelay_Type -- ------------------ procedure Undelay_Type (T : Entity_Id) is begin Set_Has_Delayed_Freeze (T, False); Set_Freeze_Node (T, Empty); -- Since we don't want T to have a Freeze_Node, we don't want its -- Full_View or Corresponding_Record_Type to have one either. -- ??? Fundamentally, this whole handling is a kludge. What we really -- want is to be sure that for an Itype that's part of record R and is a -- subtype of type T, that it's frozen after the later of the freeze -- points of R and T. We have no way of doing that directly, so what we -- do is force most such Itypes to be frozen as part of freezing R via -- this procedure and only delay the ones that need to be delayed -- (mostly the designated types of access types that are defined as part -- of the record). if Is_Private_Type (T) and then Present (Full_View (T)) and then Is_Itype (Full_View (T)) and then Is_Record_Type (Scope (Full_View (T))) then Undelay_Type (Full_View (T)); end if; if Is_Concurrent_Type (T) and then Present (Corresponding_Record_Type (T)) and then Is_Itype (Corresponding_Record_Type (T)) and then Is_Record_Type (Scope (Corresponding_Record_Type (T))) then Undelay_Type (Corresponding_Record_Type (T)); end if; end Undelay_Type; ------------------ -- Warn_Overlay -- ------------------ procedure Warn_Overlay (Expr : Node_Id; Typ : Entity_Id; Nam : Entity_Id) is Ent : constant Entity_Id := Entity (Nam); -- The object to which the address clause applies Init : Node_Id; Old : Entity_Id := Empty; Decl : Node_Id; begin -- No warning if address clause overlay warnings are off if not Address_Clause_Overlay_Warnings then return; end if; -- No warning if there is an explicit initialization Init := Original_Node (Expression (Declaration_Node (Ent))); if Present (Init) and then Comes_From_Source (Init) then return; end if; -- We only give the warning for non-imported entities of a type for -- which a non-null base init proc is defined, or for 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. if Present (Expr) and then not Is_Imported (Ent) and then not Initialization_Suppressed (Typ) 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; Decl := Next (Parent (Expr)); -- If a pragma Import follows, we assume that it is for the current -- target of the address clause, and skip the warning. if Present (Decl) and then Nkind (Decl) = N_Pragma and then Pragma_Name (Decl) = Name_Import then return; end if; if Present (Old) then Error_Msg_Node_2 := Old; Error_Msg_N ("default initialization of & may modify &?", Nam); else Error_Msg_N ("default initialization of & may modify overlaid storage?", Nam); end if; -- Add friendly warning if initialization comes from a packed array -- component. if Is_Record_Type (Typ) then declare Comp : Entity_Id; begin Comp := First_Component (Typ); while Present (Comp) loop if Nkind (Parent (Comp)) = N_Component_Declaration and then Present (Expression (Parent (Comp))) then exit; elsif Is_Array_Type (Etype (Comp)) and then Present (Packed_Array_Type (Etype (Comp))) then Error_Msg_NE ("\packed array component& " & "will be initialized to zero?", Nam, Comp); exit; else Next_Component (Comp); end if; end loop; end; end if; Error_Msg_N ("\use pragma Import for & to " & "suppress initialization (RM B.1(24))?", Nam); end if; end Warn_Overlay; end Freeze;
Go to most recent revision | Compare with Previous | Blame | View Log