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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- F R E E Z E --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2009, 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. --
-- --
-- You should have received a copy of the GNU General Public License along --
-- with this program; see file COPYING3. If not see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- 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 Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Restrict; use Restrict;
with Rident; use Rident;
with Sem; use Sem;
with Sem_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;
Loc : Source_Ptr;
Result : in out List_Id);
-- Freezes Ent using Freeze_Entity, and appends the resulting list of
-- nodes to Result, modifying Result from No_List if necessary.
procedure Freeze_Enumeration_Type (Typ : Entity_Id);
-- Freeze enumeration type. The Esize field is set as processing
-- proceeds (i.e. set by default when the type is declared and then
-- adjusted by rep clauses. What this procedure does is to make sure
-- that if a foreign convention is specified, and no specific size
-- is given, then the size must be at least Integer'Size.
procedure Freeze_Static_Object (E : Entity_Id);
-- If an object is frozen which has Is_Statically_Allocated set, then
-- all referenced types must also be marked with this flag. This routine
-- is in charge of meeting this requirement for the object entity E.
procedure Freeze_Subprogram (E : Entity_Id);
-- Perform freezing actions for a subprogram (create extra formals,
-- and set proper default mechanism values). Note that this routine
-- is not called for internal subprograms, for which neither of these
-- actions is needed (or desirable, we do not want for example to have
-- these extra formals present in initialization procedures, where they
-- would serve no purpose). In this call E is either a subprogram or
-- a subprogram type (i.e. an access to a subprogram).
function Is_Fully_Defined (T : Entity_Id) return Boolean;
-- True if T is not private and has no private components, or has a full
-- view. Used to determine whether the designated type of an access type
-- should be frozen when the access type is frozen. This is done when an
-- allocator is frozen, or an expression that may involve attributes of
-- the designated type. Otherwise freezing the access type does not freeze
-- the designated type.
procedure Process_Default_Expressions
(E : Entity_Id;
After : in out Node_Id);
-- This procedure is called for each subprogram to complete processing
-- of default expressions at the point where all types are known to be
-- frozen. The expressions must be analyzed in full, to make sure that
-- all error processing is done (they have only been pre-analyzed). If
-- the expression is not an entity or literal, its analysis may generate
-- code which must not be executed. In that case we build a function
-- body to hold that code. This wrapper function serves no other purpose
-- (it used to be called to evaluate the default, but now the default is
-- inlined at each point of call).
procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id);
-- Typ is a record or array type that is being frozen. This routine
-- sets the default component alignment from the scope stack values
-- if the alignment is otherwise not specified.
procedure Check_Debug_Info_Needed (T : Entity_Id);
-- As each entity is frozen, this routine is called to deal with the
-- setting of Debug_Info_Needed for the entity. This flag is set if
-- the entity comes from source, or if we are in Debug_Generated_Code
-- mode or if the -gnatdV debug flag is set. However, it never sets
-- the flag if Debug_Info_Off is set. 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_Node : constant Node_Id := Build_Renamed_Body (Decl, New_S);
begin
Insert_After (After, Body_Node);
Mark_Rewrite_Insertion (Body_Node);
Analyze (Body_Node);
After := Body_Node;
end Build_And_Analyze_Renamed_Body;
------------------------
-- Build_Renamed_Body --
------------------------
function Build_Renamed_Body
(Decl : Node_Id;
New_S : Entity_Id) return Node_Id
is
Loc : constant Source_Ptr := Sloc (New_S);
-- We use for the source location of the renamed body, the location
-- of the spec entity. It might seem more natural to use the location
-- of the renaming declaration itself, but that would be wrong, since
-- then the body we create would look as though it was created far
-- too late, and this could cause problems with elaboration order
-- analysis, particularly in connection with instantiations.
N : constant Node_Id := Unit_Declaration_Node (New_S);
Nam : constant Node_Id := Name (N);
Old_S : Entity_Id;
Spec : constant Node_Id := New_Copy_Tree (Specification (Decl));
Actuals : List_Id := No_List;
Call_Node : Node_Id;
Call_Name : Node_Id;
Body_Node : Node_Id;
Formal : Entity_Id;
O_Formal : Entity_Id;
Param_Spec : Node_Id;
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;
-- The original name may have been overloaded, but
-- is fully resolved now.
Set_Is_Overloaded (Call_Name, False);
end if;
-- For simple renamings, subsequent calls can be expanded directly as
-- called to the renamed entity. The body must be generated in any case
-- for calls they may appear elsewhere.
if (Ekind (Old_S) = E_Function
or else Ekind (Old_S) = E_Procedure)
and then Nkind (Decl) = N_Subprogram_Declaration
then
Set_Body_To_Inline (Decl, Old_S);
end if;
-- The body generated for this renaming is an internal artifact, and
-- does not constitute a freeze point for the called entity.
Set_Must_Not_Freeze (Call_Name);
Formal := First_Formal (Defining_Entity (Decl));
if Present (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 we have no initialization of any kind, then we don't need to
-- place any restrictions on the address clause, because the object
-- will be elaborated after the address clause is evaluated. This
-- happens if the declaration has no initial expression, or the type
-- has no implicit initialization, or the object is imported.
-- The same holds for all initialized scalar types and all access
-- types. Packed bit arrays of size up to 64 are represented using a
-- modular type with an initialization (to zero) and can be processed
-- like other initialized scalar types.
-- If the type is controlled, code to attach the object to a
-- finalization chain is generated at the point of declaration,
-- and therefore the elaboration of the object cannot be delayed:
-- the address expression must be a constant.
if (No (Expression (Decl))
and then not Needs_Finalization (Typ)
and then
(not Has_Non_Null_Base_Init_Proc (Typ)
or else Is_Imported (E)))
or else
(Present (Expression (Decl))
and then Is_Scalar_Type (Typ))
or else
Is_Access_Type (Typ)
or else
(Is_Bit_Packed_Array (Typ)
and then
Is_Modular_Integer_Type (Packed_Array_Type (Typ)))
then
null;
-- Otherwise, we require the address clause to be constant because
-- the call to the initialization procedure (or the attach code) has
-- to happen at the point of the declaration.
-- Actually the IP call has been moved to the freeze actions
-- anyway, so maybe we can relax this restriction???
else
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 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;
-- Don't bother if alignment clause with a value other than 1 is
-- present, because size may be padded up to meet back end alignment
-- requirements, and only the back end knows the rules!
elsif Known_Alignment (T) and then Alignment (T) /= 1 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);
elsif Unknown_Esize (T) then
Set_Esize (T, S);
end if;
-- Set sizes if not set already
else
if Unknown_Esize (T) then
Set_Esize (T, S);
end if;
if Unknown_RM_Size (T) then
Set_RM_Size (T, S);
end if;
end if;
end Set_Small_Size;
----------------
-- Size_Known --
----------------
function Size_Known (T : Entity_Id) return Boolean is
Index : Entity_Id;
Comp : Entity_Id;
Ctyp : Entity_Id;
Low : Node_Id;
High : Node_Id;
begin
if Size_Known_At_Compile_Time (T) then
return True;
-- 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
-- discriminanted components.
elsif T /= Base_Type (T)
and then not Static_Discriminated_Components (T)
then
return False;
-- Don't do any recursion on type with error posted, since we may
-- have a malformed type that leads us into a loop.
elsif Error_Posted (T) then
return False;
end if;
-- Now look at the components of the record
declare
-- The following two variables are used to keep track of the
-- size of packed records if we can tell the size of the packed
-- record in the front end. Packed_Size_Known is True if so far
-- we can figure out the size. It is initialized to True for a
-- packed record, unless the record has discriminants. The
-- reason we eliminate the discriminated case is that we don't
-- know the way the back end lays out discriminated packed
-- records. If Packed_Size_Known is True, then Packed_Size is
-- the size in bits so far.
Packed_Size_Known : Boolean :=
Is_Packed (T)
and then not Has_Discriminants (T);
Packed_Size : Uint := Uint_0;
begin
-- Test for variant part present
if Has_Discriminants (T)
and then Present (Parent (T))
and then Nkind (Parent (T)) = N_Full_Type_Declaration
and then Nkind (Type_Definition (Parent (T))) =
N_Record_Definition
and then not Null_Present (Type_Definition (Parent (T)))
and then Present (Variant_Part
(Component_List (Type_Definition (Parent (T)))))
then
-- If variant part is present, and type is unconstrained,
-- then we must have defaulted discriminants, or a size
-- clause must be present for the type, or else the size
-- is definitely not known at compile time.
if not Is_Constrained (T)
and then
No (Discriminant_Default_Value
(First_Discriminant (T)))
and then Unknown_Esize (T)
then
return False;
end if;
end if;
-- Loop through components
Comp := First_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 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_Defining_Identifier (Loc,
New_Internal_Name ('T'));
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
Loc : constant Source_Ptr := Sloc (After);
E : Entity_Id;
Decl : Node_Id;
procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id);
-- This is the internal recursive routine that does freezing of entities
-- (but NOT the analysis of default expressions, which should not be
-- recursive, we don't want to analyze those till we are sure that ALL
-- the types are frozen).
--------------------
-- Freeze_All_Ent --
--------------------
procedure Freeze_All_Ent
(From : Entity_Id;
After : in out Node_Id)
is
E : Entity_Id;
Flist : List_Id;
Lastn : Node_Id;
procedure Process_Flist;
-- If freeze nodes are present, insert and analyze, and reset cursor
-- for next insertion.
-------------------
-- Process_Flist --
-------------------
procedure Process_Flist is
begin
if Is_Non_Empty_List (Flist) then
Lastn := Next (After);
Insert_List_After_And_Analyze (After, Flist);
if Present (Lastn) then
After := Prev (Lastn);
else
After := Last (List_Containing (After));
end if;
end if;
end Process_Flist;
-- Start or processing for Freeze_All_Ent
begin
E := From;
while Present (E) loop
-- If the entity is an inner package which is not a package
-- renaming, then its entities must be frozen at this point. Note
-- that such entities do NOT get frozen at the end of the nested
-- package itself (only library packages freeze).
-- Same is true for task declarations, where anonymous records
-- created for entry parameters must be frozen.
if Ekind (E) = E_Package
and then No (Renamed_Object (E))
and then not Is_Child_Unit (E)
and then not Is_Frozen (E)
then
Push_Scope (E);
Install_Visible_Declarations (E);
Install_Private_Declarations (E);
Freeze_All (First_Entity (E), After);
End_Package_Scope (E);
elsif Ekind (E) in Task_Kind
and then
(Nkind (Parent (E)) = N_Task_Type_Declaration
or else
Nkind (Parent (E)) = N_Single_Task_Declaration)
then
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, Loc);
Process_Flist;
end if;
Next_Elmt (Prim);
end loop;
end;
end if;
if not Is_Frozen (E) then
Flist := Freeze_Entity (E, Loc);
Process_Flist;
end if;
-- If an incomplete type is still not frozen, this may be a
-- premature freezing because of a body declaration that follows.
-- Indicate where the freezing took place.
-- If the freezing is caused by the end of the current declarative
-- part, it is a Taft Amendment type, and there is no error.
if not Is_Frozen (E)
and then Ekind (E) = E_Incomplete_Type
then
declare
Bod : constant Node_Id := Next (After);
begin
if (Nkind (Bod) = N_Subprogram_Body
or else Nkind (Bod) = N_Entry_Body
or else Nkind (Bod) = N_Package_Body
or else Nkind (Bod) = N_Protected_Body
or else Nkind (Bod) = N_Task_Body
or else Nkind (Bod) in N_Body_Stub)
and then
List_Containing (After) = List_Containing (Parent (E))
then
Error_Msg_Sloc := Sloc (Next (After));
Error_Msg_NE
("type& is frozen# before its full declaration",
Parent (E), E);
end if;
end;
end if;
Next_Entity (E);
end loop;
end Freeze_All_Ent;
-- Start of processing for Freeze_All
begin
Freeze_All_Ent (From, After);
-- Now that all types are frozen, we can deal with default expressions
-- that require us to build a default expression functions. This is the
-- point at which such functions are constructed (after all types that
-- might be used in such expressions have been frozen).
-- We also add finalization chains to access types whose designated
-- types are controlled. This is normally done when freezing the type,
-- but this misses recursive type definitions where the later members
-- of the recursion introduce controlled components.
-- Loop through entities
E := From;
while Present (E) loop
if Is_Subprogram (E) then
if not Default_Expressions_Processed (E) then
Process_Default_Expressions (E, After);
end if;
if not Has_Completion (E) then
Decl := Unit_Declaration_Node (E);
if Nkind (Decl) = N_Subprogram_Renaming_Declaration then
Build_And_Analyze_Renamed_Body (Decl, E, After);
elsif Nkind (Decl) = N_Subprogram_Declaration
and then Present (Corresponding_Body (Decl))
and then
Nkind (Unit_Declaration_Node (Corresponding_Body (Decl)))
= N_Subprogram_Renaming_Declaration
then
Build_And_Analyze_Renamed_Body
(Decl, Corresponding_Body (Decl), After);
end if;
end if;
elsif Ekind (E) in Task_Kind
and then
(Nkind (Parent (E)) = N_Task_Type_Declaration
or else
Nkind (Parent (E)) = N_Single_Task_Declaration)
then
declare
Ent : Entity_Id;
begin
Ent := First_Entity (E);
while Present (Ent) loop
if Is_Entry (Ent)
and then not Default_Expressions_Processed (Ent)
then
Process_Default_Expressions (Ent, After);
end if;
Next_Entity (Ent);
end loop;
end;
elsif Is_Access_Type (E)
and then Comes_From_Source (E)
and then Ekind (Directly_Designated_Type (E)) = E_Incomplete_Type
and then Needs_Finalization (Designated_Type (E))
and then No (Associated_Final_Chain (E))
then
Build_Final_List (Parent (E), E);
end if;
Next_Entity (E);
end loop;
end Freeze_All;
-----------------------
-- Freeze_And_Append --
-----------------------
procedure Freeze_And_Append
(Ent : Entity_Id;
Loc : Source_Ptr;
Result : in out List_Id)
is
L : constant List_Id := Freeze_Entity (Ent, Loc);
begin
if Is_Non_Empty_List (L) then
if Result = No_List then
Result := L;
else
Append_List (L, Result);
end if;
end if;
end Freeze_And_Append;
-------------------
-- Freeze_Before --
-------------------
procedure Freeze_Before (N : Node_Id; T : Entity_Id) is
Freeze_Nodes : constant List_Id := Freeze_Entity (T, Sloc (N));
begin
if Is_Non_Empty_List (Freeze_Nodes) then
Insert_Actions (N, Freeze_Nodes);
end if;
end Freeze_Before;
-------------------
-- Freeze_Entity --
-------------------
function Freeze_Entity (E : Entity_Id; Loc : Source_Ptr) return List_Id is
Test_E : Entity_Id := E;
Comp : Entity_Id;
F_Node : Node_Id;
Result : List_Id;
Indx : Node_Id;
Formal : Entity_Id;
Atype : Entity_Id;
Has_Default_Initialization : Boolean := False;
-- This flag gets set to true for a variable with default initialization
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.
----------------------------
-- 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
Rec_Type : constant Entity_Id :=
Scope (Defining_Identifier (Comp_Decl));
Decl : constant Node_Id := Parent (Rec_Type);
function Process (N : Node_Id) return Traverse_Result;
-- Process routine to apply check to given node
-------------
-- Process --
-------------
function Process (N : Node_Id) return Traverse_Result is
begin
case Nkind (N) is
when N_Attribute_Reference =>
if (Attribute_Name (N) = Name_Access
or else
Attribute_Name (N) = Name_Unchecked_Access)
and then Is_Entity_Name (Prefix (N))
and then Is_Type (Entity (Prefix (N)))
and then Entity (Prefix (N)) = E
then
Error_Msg_N
("current instance must be a limited type", Prefix (N));
return Abandon;
else
return OK;
end if;
when others => return OK;
end case;
end Process;
procedure Traverse is new Traverse_Proc (Process);
-- Start of processing for Check_Current_Instance
begin
-- In Ada95, the (imprecise) rule is that the current instance of a
-- limited type is aliased. In Ada2005, limitedness must be explicit:
-- either a tagged type, or a limited record.
if Is_Limited_Type (Rec_Type)
and then (Ada_Version < Ada_05 or else Is_Tagged_Type (Rec_Type))
then
return;
elsif Nkind (Decl) = N_Full_Type_Declaration
and then Limited_Present (Type_Definition (Decl))
then
return;
else
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);
if No (Result) then
Result := New_List (IR);
else
Append (IR, Result);
end if;
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
-- If this is a subtype of a controlled type, declared without a
-- constraint, the _controller may not appear in the component list
-- if the parent was not frozen at the point of subtype declaration.
-- Inherit the _controller component now.
if Rec /= Base_Type (Rec)
and then Has_Controlled_Component (Rec)
then
if Nkind (Parent (Rec)) = N_Subtype_Declaration
and then Is_Entity_Name (Subtype_Indication (Parent (Rec)))
then
Set_First_Entity (Rec, First_Entity (Base_Type (Rec)));
-- If this is an internal type without a declaration, as for
-- record component, the base type may not yet be frozen, and its
-- controller has not been created. Add an explicit freeze node
-- for the itype, so it will be frozen after the base type. This
-- freeze node is used to communicate with the expander, in order
-- to create the controller for the enclosing record, and it is
-- deleted afterwards (see exp_ch3). It must not be created when
-- expansion is off, because it might appear in the wrong context
-- for the back end.
elsif Is_Itype (Rec)
and then Has_Delayed_Freeze (Base_Type (Rec))
and then
Nkind (Associated_Node_For_Itype (Rec)) =
N_Component_Declaration
and then Expander_Active
then
Ensure_Freeze_Node (Rec);
end if;
end if;
-- Freeze components and embedded subtypes
Comp := First_Entity (Rec);
Prev := Empty;
while Present (Comp) loop
-- First handle the (real) component case
if Ekind (Comp) = E_Component
or else Ekind (Comp) = E_Discriminant
then
declare
CC : constant Node_Id := Component_Clause (Comp);
begin
-- Freezing a record type freezes the type of each of its
-- components. However, if the type of the component is
-- part of this record, we do not want or need a separate
-- Freeze_Node. Note that Is_Itype is wrong because that's
-- also set in private type cases. We also can't check for
-- the Scope being exactly Rec because of private types and
-- record extensions.
if Is_Itype (Etype (Comp))
and then Is_Record_Type (Underlying_Type
(Scope (Etype (Comp))))
then
Undelay_Type (Etype (Comp));
end if;
Freeze_And_Append (Etype (Comp), Loc, Result);
-- Check for error of component clause given for variable
-- sized type. We have to delay this test till this point,
-- since the component type has to be frozen for us to know
-- if it is variable length. We omit this test in a generic
-- context, it will be applied at instantiation time.
if Present (CC) then
Placed_Component := True;
if Inside_A_Generic then
null;
elsif not
Size_Known_At_Compile_Time
(Underlying_Type (Etype (Comp)))
then
Error_Msg_N
("component clause not allowed for variable " &
"length component", CC);
end if;
else
Unplaced_Component := True;
end if;
-- Case of component requires byte alignment
if Must_Be_On_Byte_Boundary (Etype (Comp)) then
-- Set the enclosing record to also require byte align
Set_Must_Be_On_Byte_Boundary (Rec);
-- Check for component clause that is inconsistent with
-- the required byte boundary alignment.
if Present (CC)
and then Normalized_First_Bit (Comp) mod
System_Storage_Unit /= 0
then
Error_Msg_N
("component & must be byte aligned",
Component_Name (Component_Clause (Comp)));
end if;
end if;
-- If component clause is present, then deal with the non-
-- default bit order case for Ada 95 mode. The required
-- processing for Ada 2005 mode is handled separately after
-- processing all components.
-- We only do this processing for the base type, and in
-- fact that's important, since otherwise if there are
-- record subtypes, we could reverse the bits once for
-- each subtype, which would be incorrect.
if Present (CC)
and then Reverse_Bit_Order (Rec)
and then Ekind (E) = E_Record_Type
and then Ada_Version <= Ada_95
then
declare
CFB : constant Uint := Component_Bit_Offset (Comp);
CSZ : constant Uint := Esize (Comp);
CLC : constant Node_Id := Component_Clause (Comp);
Pos : constant Node_Id := Position (CLC);
FB : constant Node_Id := First_Bit (CLC);
Storage_Unit_Offset : constant Uint :=
CFB / System_Storage_Unit;
Start_Bit : constant Uint :=
CFB mod System_Storage_Unit;
begin
-- Cases where field goes over storage unit boundary
if Start_Bit + CSZ > System_Storage_Unit then
-- Allow multi-byte field but generate warning
if Start_Bit mod System_Storage_Unit = 0
and then CSZ mod System_Storage_Unit = 0
then
Error_Msg_N
("multi-byte field specified with non-standard"
& " Bit_Order?", CLC);
if Bytes_Big_Endian then
Error_Msg_N
("bytes are not reversed "
& "(component is big-endian)?", CLC);
else
Error_Msg_N
("bytes are not reversed "
& "(component is little-endian)?", CLC);
end if;
-- Do not allow non-contiguous field
else
Error_Msg_N
("attempt to specify non-contiguous field "
& "not permitted", CLC);
Error_Msg_N
("\caused by non-standard Bit_Order "
& "specified", CLC);
Error_Msg_N
("\consider possibility of using "
& "Ada 2005 mode here", CLC);
end if;
-- Case where field fits in one storage unit
else
-- Give warning if suspicious component clause
if Intval (FB) >= System_Storage_Unit
and then Warn_On_Reverse_Bit_Order
then
Error_Msg_N
("?Bit_Order clause does not affect " &
"byte ordering", Pos);
Error_Msg_Uint_1 :=
Intval (Pos) + Intval (FB) /
System_Storage_Unit;
Error_Msg_N
("?position normalized to ^ before bit " &
"order interpreted", Pos);
end if;
-- Here is where we fix up the Component_Bit_Offset
-- value to account for the reverse bit order.
-- Some examples of what needs to be done are:
-- First_Bit .. Last_Bit Component_Bit_Offset
-- old new old new
-- 0 .. 0 7 .. 7 0 7
-- 0 .. 1 6 .. 7 0 6
-- 0 .. 2 5 .. 7 0 5
-- 0 .. 7 0 .. 7 0 4
-- 1 .. 1 6 .. 6 1 6
-- 1 .. 4 3 .. 6 1 3
-- 4 .. 7 0 .. 3 4 0
-- The general rule is that the first bit is
-- is obtained by subtracting the old ending bit
-- from storage_unit - 1.
Set_Component_Bit_Offset
(Comp,
(Storage_Unit_Offset * System_Storage_Unit) +
(System_Storage_Unit - 1) -
(Start_Bit + CSZ - 1));
Set_Normalized_First_Bit
(Comp,
Component_Bit_Offset (Comp) mod
System_Storage_Unit);
end if;
end;
end if;
end;
end if;
-- Gather data for possible Implicit_Packing later
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)), Loc, Result);
elsif
Nkind (Expression (Alloc)) = N_Subtype_Indication
then
Freeze_And_Append
(Entity (Subtype_Mark (Expression (Alloc))),
Loc, Result);
end if;
elsif Is_Itype (Designated_Type (Etype (Comp))) then
Check_Itype (Etype (Comp));
else
Freeze_And_Append
(Designated_Type (Etype (Comp)), Loc, 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))), Loc, Result);
end if;
Prev := Comp;
Next_Entity (Comp);
end loop;
-- Deal with pragma 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 Ada 2005 processing for bit order (the Ada
-- 95 case was already taken care of above).
elsif Ada_Version >= Ada_05 then
Adjust_Record_For_Reverse_Bit_Order (Rec);
end if;
end if;
-- Set OK_To_Reorder_Components depending on debug flags
if Rec = 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
("?pragma Pack has no effect, no unplaced components",
Get_Rep_Pragma (Rec, Name_Pack));
end if;
end if;
-- If this is the record corresponding to a remote type, freeze the
-- remote type here since that is what we are semantically freezing.
-- This prevents the freeze node for that type in an inner scope.
-- Also, Check for controlled components and unchecked unions.
-- Finally, enforce the restriction that access attributes with a
-- current instance prefix can only apply to limited types.
if Ekind (Rec) = E_Record_Type then
if Present (Corresponding_Remote_Type (Rec)) then
Freeze_And_Append
(Corresponding_Remote_Type (Rec), Loc, Result);
end if;
Comp := First_Component (Rec);
while Present (Comp) loop
-- 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);
exit;
end if;
if Has_Unchecked_Union (Etype (Comp)) then
Set_Has_Unchecked_Union (Rec);
end if;
if Has_Per_Object_Constraint (Comp) then
-- Scan component declaration for likely misuses of current
-- instance, either in a constraint or a default expression.
Check_Current_Instance (Parent (Comp));
end if;
Next_Component (Comp);
end loop;
end if;
Set_Component_Alignment_If_Not_Set (Rec);
-- For first subtypes, check if there are any fixed-point fields with
-- component clauses, where we must check the size. This is not done
-- till the freeze point, since for fixed-point types, we do not know
-- the size until the type is frozen. Similar processing applies to
-- bit packed arrays.
if Is_First_Subtype (Rec) then
Comp := First_Component (Rec);
while Present (Comp) loop
if Present (Component_Clause (Comp))
and then (Is_Fixed_Point_Type (Etype (Comp))
or else
Is_Bit_Packed_Array (Etype (Comp)))
then
Check_Size
(Component_Name (Component_Clause (Comp)),
Etype (Comp),
Esize (Comp),
Junk);
end if;
Next_Component (Comp);
end loop;
end if;
-- 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 Esize (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 Esize (Rec) >= Scalar_Component_Total_RM_Size
-- Never do implicit packing in CodePeer mode since we don't do
-- any packing ever in this mode (why not???)
and then not CodePeer_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;
-- 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 := Current_Scope;
begin
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 := Scope (Test_E);
begin
while Present (S) loop
if Is_Generic_Instance (S) then
exit;
else
S := Scope (S);
end if;
end loop;
if No (S) then
return No_List;
end if;
end;
end if;
-- Here to freeze the entity
Result := No_List;
Set_Is_Frozen (E);
-- Case of entity being frozen is other than a type
if not Is_Type (E) then
-- If entity is exported or imported and does not have an external
-- name, now is the time to provide the appropriate default name.
-- Skip this if the entity is stubbed, since we don't need a name
-- for any stubbed routine. 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);
Freeze_And_Append (F_Type, Loc, Result);
if Is_Private_Type (F_Type)
and then Is_Private_Type (Base_Type (F_Type))
and then No (Full_View (Base_Type (F_Type)))
and then not Is_Generic_Type (F_Type)
and then not Is_Derived_Type (F_Type)
then
-- If the type of a formal is incomplete, subprogram
-- is being frozen prematurely. Within an instance
-- (but not within a wrapper package) this is an
-- 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, Loc, 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);
Freeze_And_Append (R_Type, Loc, 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 suspicous 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 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), Loc, 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), Loc, 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 Suppress_Init_Proc (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_Intialization, 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.
if Present (Scope (E))
and then Is_Generic_Unit (Scope (E))
then
Check_Compile_Time_Size (E);
return No_List;
end if;
-- Deal with special cases of freezing for subtype
if E /= Base_Type (E) then
-- 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_Esize (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_Esize (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
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
("\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.
Atype := Ancestor_Subtype (E);
if Present (Atype) then
Freeze_And_Append (Atype, Loc, Result);
-- Otherwise freeze the base type of the entity before freezing
-- the entity itself (RM 13.14(15)).
elsif E /= Base_Type (E) then
Freeze_And_Append (Base_Type (E), Loc, Result);
end if;
-- For a derived type, freeze its parent type first (RM 13.14(15))
elsif Is_Derived_Type (E) then
Freeze_And_Append (Etype (E), Loc, Result);
Freeze_And_Append (First_Subtype (Etype (E)), Loc, Result);
end if;
-- For array type, freeze index types and component type first
-- before freezing the array (RM 13.14(15)).
if Is_Array_Type (E) then
declare
Ctyp : constant Entity_Id := Component_Type (E);
Non_Standard_Enum : Boolean := False;
-- Set true if any of the index types is an enumeration type
-- with a non-standard representation.
begin
Freeze_And_Append (Ctyp, Loc, Result);
Indx := First_Index (E);
while Present (Indx) loop
Freeze_And_Append (Etype (Indx), Loc, Result);
if Is_Enumeration_Type (Etype (Indx))
and then Has_Non_Standard_Rep (Etype (Indx))
then
Non_Standard_Enum := True;
end if;
Next_Index (Indx);
end loop;
-- Processing that is done only for base types
if Ekind (E) = E_Array_Type then
-- Propagate flags for component type
if Is_Controlled (Component_Type (E))
or else Has_Controlled_Component (Ctyp)
then
Set_Has_Controlled_Component (E);
end if;
if Has_Unchecked_Union (Component_Type (E)) then
Set_Has_Unchecked_Union (E);
end if;
-- If packing was requested or if the component size was set
-- explicitly, then see if bit packing is required. This
-- processing is only done for base types, since all the
-- representation aspects involved are type-related. This
-- is not just an optimization, if we start processing the
-- subtypes, they 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 not Has_Atomic_Components (E)
and then Known_Static_RM_Size (Ctyp)
then
Csiz := UI_Max (RM_Size (Ctyp), 1);
elsif Known_Component_Size (E) then
Csiz := Component_Size (E);
elsif not Known_Static_Esize (Ctyp) then
Csiz := Uint_0;
else
Esiz := Esize (Ctyp);
-- We can set the component size if it is less than
-- 16, rounding it up to the next storage unit size.
if Esiz <= 8 then
Csiz := Uint_8;
elsif Esiz <= 16 then
Csiz := Uint_16;
else
Csiz := Uint_0;
end if;
-- Set component size up to match alignment if it
-- would otherwise be less than the alignment. This
-- deals with cases of types whose alignment exceeds
-- their 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)
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);
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);
-- In all other cases, packing is indeed needed
else
Set_Has_Non_Standard_Rep (Base_Type (E));
Set_Is_Bit_Packed_Array (Base_Type (E));
Set_Is_Packed (Base_Type (E));
end if;
end;
end if;
end;
-- Processing that is done only for subtypes
else
-- Acquire alignment from base type
if Unknown_Alignment (E) then
Set_Alignment (E, Alignment (Base_Type (E)));
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), Loc, 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), Loc, 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);
if No (Result) then
Result := New_List (Ref);
else
Append (Ref, Result);
end if;
end;
end if;
-- The equivalent type associated with a class-wide subtype needs
-- to be frozen to ensure that its layout is done.
if Ekind (E) = E_Class_Wide_Subtype
and then Present (Equivalent_Type (E))
then
Freeze_And_Append (Equivalent_Type (E), Loc, Result);
end if;
-- For a record (sub)type, freeze all the component types (RM
-- 13.14(15). We test for E_Record_(sub)Type here, rather than using
-- Is_Record_Type, because we don't want to attempt the freeze for
-- the case of a private type with record extension (we will do that
-- later when the full type is frozen).
elsif Ekind (E) = E_Record_Type
or else Ekind (E) = E_Record_Subtype
then
Freeze_Record_Type (E);
-- For a concurrent type, freeze corresponding record type. This
-- does not 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), Loc, Result);
end if;
Comp := First_Entity (E);
while Present (Comp) loop
if Is_Type (Comp) then
Freeze_And_Append (Comp, Loc, Result);
elsif (Ekind (Comp)) /= E_Function then
if Is_Itype (Etype (Comp))
and then Underlying_Type (Scope (Etype (Comp))) = E
then
Undelay_Type (Etype (Comp));
end if;
Freeze_And_Append (Etype (Comp), Loc, Result);
end if;
Next_Entity (Comp);
end loop;
-- Private types are required to point to the same freeze node as
-- their corresponding full views. The freeze node itself has to
-- point to the partial view of the entity (because from the partial
-- view, we can retrieve the full view, but not the reverse).
-- However, in order to freeze correctly, we need to freeze the full
-- view. If we are freezing at the end of a scope (or within the
-- scope of the private type), the partial and full views will have
-- been swapped, the full view appears first in the entity chain and
-- the swapping mechanism ensures that the pointers are properly set
-- (on scope exit).
-- If we encounter the partial view before the full view (e.g. when
-- freezing from another scope), we freeze the full view, and then
-- set the pointers appropriately since we cannot rely on swapping to
-- fix things up (subtypes in an outer scope might not get swapped).
elsif Is_Incomplete_Or_Private_Type (E)
and then not Is_Generic_Type (E)
then
-- 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), Loc, Result);
end if;
Freeze_And_Append (Full, Loc, Result);
if Has_Delayed_Freeze (E) then
F_Node := Freeze_Node (Full);
if Present (F_Node) then
Set_Freeze_Node (E, F_Node);
Set_Entity (F_Node, E);
else
-- {Incomplete,Private}_Subtypes with Full_Views
-- constrained by discriminants.
Set_Has_Delayed_Freeze (E, False);
Set_Freeze_Node (E, Empty);
end if;
end if;
end;
Check_Debug_Info_Needed (E);
end if;
-- AI-117 requires that the convention of a partial view be the
-- same as the convention of the full view. Note that this is a
-- recognized breach of privacy, but it's essential for logical
-- consistency of representation, and the lack of a rule in
-- RM95 was an oversight.
Set_Convention (E, Convention (Full_View (E)));
Set_Size_Known_At_Compile_Time (E,
Size_Known_At_Compile_Time (Full_View (E)));
-- Size information is copied from the full view to the
-- incomplete or private view for consistency.
-- We skip this is the full view is not a type. This is very
-- strange of course, and can only happen as a result of
-- certain illegalities, such as a premature attempt to derive
-- from an incomplete type.
if Is_Type (Full_View (E)) then
Set_Size_Info (E, Full_View (E));
Set_RM_Size (E, RM_Size (Full_View (E)));
end if;
return Result;
-- Case of no full view present. If entity is derived or subtype,
-- it is safe to freeze, correctness depends on the frozen status
-- of parent. Otherwise it is either premature usage, or a Taft
-- amendment type, so diagnosis is at the point of use and the
-- type might be frozen later.
elsif E /= Base_Type (E)
or else Is_Derived_Type (E)
then
null;
else
Set_Is_Frozen (E, False);
return No_List;
end if;
-- For access subprogram, freeze types of all formals, the return
-- type was already frozen, since it is the Etype of the function.
-- 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;
else
Error_Msg_NE
("invalid use of incomplete type&", E, Etype (Formal));
end if;
end if;
Freeze_And_Append (Etype (Formal), Loc, 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), Loc, Result);
end if;
end if;
-- Generic types are never seen by the back-end, and are also not
-- processed by the expander (since the expander is turned off for
-- generic processing), so we never need freeze nodes for them.
if Is_Generic_Type (E) then
return Result;
end if;
-- Some special processing for non-generic types to complete
-- representation details not known till the freeze point.
if Is_Fixed_Point_Type (E) then
Freeze_Fixed_Point_Type (E);
-- Some error checks required for ordinary fixed-point type. Defer
-- these till the freeze-point since we need the small and range
-- values. We only do these checks for base types
if Is_Ordinary_Fixed_Point_Type (E)
and then E = Base_Type (E)
then
if Small_Value (E) < Ureal_2_M_80 then
Error_Msg_Name_1 := Name_Small;
Error_Msg_N
("`&''%` 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
-- Check restriction for standard storage pool
if No (Associated_Storage_Pool (E)) then
Check_Restriction (No_Standard_Storage_Pools, E);
end if;
-- Deal with error message for pure access type. This is not an
-- error in Ada 2005 if there is no pool (see AI-366).
if Is_Pure_Unit_Access_Type (E)
and then (Ada_Version < Ada_05
or else not No_Pool_Assigned (E))
then
Error_Msg_N ("named access type not allowed in pure unit", E);
if Ada_Version >= Ada_05 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;
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;
-- Remaining process is to set/verify the representation information,
-- in particular the size and alignment values. This processing is
-- not required for generic types, since generic types do not play
-- any part in code generation, and so the size and alignment values
-- for such types are irrelevant.
if Is_Generic_Type (E) then
return Result;
-- Otherwise we call the layout procedure
else
Layout_Type (E);
end if;
-- End of freeze processing for type entities
end if;
-- Here is where we logically freeze the current entity. If it has a
-- freeze node, then this is the point at which the freeze node is
-- linked into the result list.
if Has_Delayed_Freeze (E) then
-- If a freeze node is already allocated, use it, otherwise allocate
-- a new one. The preallocation happens in the case of anonymous base
-- types, where we preallocate so that we can set First_Subtype_Link.
-- Note that we reset the Sloc to the current freeze location.
if Present (Freeze_Node (E)) then
F_Node := Freeze_Node (E);
Set_Sloc (F_Node, Loc);
else
F_Node := New_Node (N_Freeze_Entity, Loc);
Set_Freeze_Node (E, F_Node);
Set_Access_Types_To_Process (F_Node, No_Elist);
Set_TSS_Elist (F_Node, No_Elist);
Set_Actions (F_Node, No_List);
end if;
Set_Entity (F_Node, E);
if Result = No_List then
Result := New_List (F_Node);
else
Append (F_Node, Result);
end if;
-- A final pass over record types with discriminants. If the type
-- has an incomplete declaration, there may be constrained access
-- subtypes declared elsewhere, which do not depend on the discrimi-
-- nants of the type, and which are used as component types (i.e.
-- the full view is a recursive type). The designated types of these
-- subtypes can only be elaborated after the type itself, and they
-- need an itype reference.
if Ekind (E) = E_Record_Type
and then Has_Discriminants (E)
then
declare
Comp : Entity_Id;
IR : Node_Id;
Typ : Entity_Id;
begin
Comp := First_Component (E);
while Present (Comp) loop
Typ := Etype (Comp);
if Ekind (Comp) = E_Component
and then Is_Access_Type (Typ)
and then Scope (Typ) /= E
and then Base_Type (Designated_Type (Typ)) = E
and then Is_Itype (Designated_Type (Typ))
then
IR := Make_Itype_Reference (Sloc (Comp));
Set_Itype (IR, Designated_Type (Typ));
Append (IR, Result);
end if;
Next_Component (Comp);
end loop;
end;
end if;
end if;
-- When a type is frozen, the first subtype of the type is frozen as
-- well (RM 13.14(15)). This has to be done after freezing the type,
-- since obviously the first subtype depends on its own base type.
if Is_Type (E) then
Freeze_And_Append (First_Subtype (E), Loc, Result);
-- If we just froze a tagged non-class wide record, then freeze the
-- corresponding class-wide type. This must be done after the tagged
-- type itself is frozen, because the class-wide type refers to the
-- tagged type which generates the class.
if Is_Tagged_Type (E)
and then not Is_Class_Wide_Type (E)
and then Present (Class_Wide_Type (E))
then
Freeze_And_Append (Class_Wide_Type (E), Loc, Result);
end if;
end if;
Check_Debug_Info_Needed (E);
-- Special handling for subprograms
if Is_Subprogram (E) then
-- If subprogram has address clause then reset Is_Public flag, since
-- we do not want the backend to generate external references.
if Present (Address_Clause (E))
and then not Is_Library_Level_Entity (E)
then
Set_Is_Public (E, False);
-- If no address clause and not intrinsic, then for imported
-- subprogram in main unit, generate descriptor if we are in
-- Propagate_Exceptions mode.
elsif Propagate_Exceptions
and then Is_Imported (E)
and then not Is_Intrinsic_Subprogram (E)
and then Convention (E) /= Convention_Stubbed
then
if Result = No_List then
Result := Empty_List;
end if;
end if;
end if;
return Result;
end Freeze_Entity;
-----------------------------
-- Freeze_Enumeration_Type --
-----------------------------
procedure Freeze_Enumeration_Type (Typ : Entity_Id) is
begin
-- 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.
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);
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!)
if In_Spec_Exp
and then Nkind (N) in N_Subexpr
and then not Is_Static_Expression (N)
then
return;
end if;
-- Freeze type of expression if not frozen already
Typ := Empty;
if Nkind (N) in N_Has_Etype then
if not Is_Frozen (Etype (N)) then
Typ := Etype (N);
-- Base type may be an derived numeric type that is frozen at
-- the point of declaration, but first_subtype is still unfrozen.
elsif not Is_Frozen (First_Subtype (Etype (N))) then
Typ := First_Subtype (Etype (N));
end if;
end if;
-- For entity name, freeze entity if not frozen already. A special
-- exception occurs for an identifier that did not come from source.
-- We don't let such identifiers freeze a non-internal entity, i.e.
-- an entity that did come from source, since such an identifier was
-- generated by the expander, and cannot have any semantic effect on
-- the freezing semantics. For example, this stops the parameter of
-- an initialization procedure from freezing the variable.
if Is_Entity_Name (N)
and then not Is_Frozen (Entity (N))
and then (Nkind (N) /= N_Identifier
or else Comes_From_Source (N)
or else not Comes_From_Source (Entity (N)))
then
Nam := Entity (N);
else
Nam := Empty;
end if;
-- For an allocator freeze designated type if not frozen already
-- For an aggregate whose component type is an access type, freeze the
-- designated type now, so that its freeze does not appear within the
-- loop that might be created in the expansion of the aggregate. If the
-- designated type is a private type without full view, the expression
-- cannot contain an allocator, so the type is not frozen.
-- 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 som 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_Package_Specification |
N_Package_Body |
N_Subprogram_Body |
N_Task_Body |
N_Protected_Body |
N_Entry_Body |
N_Block_Statement => exit;
-- The expander is allowed to define types in any statements list,
-- so any of the following parent nodes also mark a freezing point
-- if the actual node is in a list of statements or declarations.
when N_Exception_Handler |
N_If_Statement |
N_Elsif_Part |
N_Case_Statement_Alternative |
N_Compilation_Unit_Aux |
N_Selective_Accept |
N_Accept_Alternative |
N_Delay_Alternative |
N_Conditional_Entry_Call |
N_Entry_Call_Alternative |
N_Triggering_Alternative |
N_Abortable_Part |
N_Freeze_Entity =>
exit when Is_List_Member (P);
-- Note: The N_Loop_Statement is a special case. A type that
-- appears in the source can never be frozen in a loop (this
-- occurs only because of a loop expanded by the expander), so we
-- keep on going. Otherwise we terminate the search. Same is true
-- of any entity which comes from source. (if they have predefined
-- type, that type does not appear to come from source, but the
-- entity should not be frozen here).
when N_Loop_Statement =>
exit when not Comes_From_Source (Etype (N))
and then (No (Nam) or else not Comes_From_Source (Nam));
-- For all other cases, keep looking at parents
when others =>
null;
end case;
-- We fall through the case if we did not yet find the proper
-- place in the free for inserting the freeze node, so climb!
P := Parent_P;
end loop;
-- If the expression appears in a record or an initialization procedure,
-- the freeze nodes are collected and attached to the current scope, to
-- be inserted and analyzed on exit from the scope, to insure that
-- generated entities appear in the correct scope. If the expression is
-- a default for a discriminant specification, the scope is still void.
-- The expression can also appear in the discriminant part of a private
-- or concurrent type.
-- If the expression appears in a constrained subcomponent of an
-- enclosing record declaration, the freeze nodes must be attached to
-- the outer record type so they can eventually be placed in the
-- enclosing declaration list.
-- The other case requiring this special handling is if we are in a
-- default expression, since in that case we are about to freeze a
-- static type, and the freeze scope needs to be the outer scope, not
-- the scope of the subprogram with the default parameter.
-- For default expressions 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
Loc : constant Source_Ptr := Sloc (Current_Scope);
Freeze_Nodes : List_Id := No_List;
Pos : Int := Scope_Stack.Last;
begin
if Present (Desig_Typ) then
Freeze_And_Append (Desig_Typ, Loc, Freeze_Nodes);
end if;
if Present (Typ) then
Freeze_And_Append (Typ, Loc, Freeze_Nodes);
end if;
if Present (Nam) then
Freeze_And_Append (Nam, Loc, Freeze_Nodes);
end if;
-- The current scope may be that of a constrained component of
-- an enclosing record declaration, which is above the current
-- scope in the scope stack.
if Is_Record_Type (Scope (Current_Scope)) then
Pos := Pos - 1;
end if;
if Is_Non_Empty_List (Freeze_Nodes) then
if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then
Scope_Stack.Table (Pos).Pending_Freeze_Actions :=
Freeze_Nodes;
else
Append_List (Freeze_Nodes, Scope_Stack.Table
(Pos).Pending_Freeze_Actions);
end if;
end if;
end;
return;
end if;
-- Now we have the right place to do the freezing. First, a special
-- adjustment, if we are in 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
(Size_Excl_EP = 8 or else
Size_Excl_EP = 16 or else
Size_Excl_EP = 32 or else
Size_Excl_EP = 64)
then
Actual_Size := Size_Excl_EP;
Actual_Lo := Loval_Excl_EP;
Actual_Hi := Hival_Excl_EP;
-- Otherwise we can definitely include the end points
else
Actual_Size := Size_Incl_EP;
Actual_Lo := Loval_Incl_EP;
Actual_Hi := Hival_Incl_EP;
end if;
-- One pathological case: normally we never fudge a low bound
-- down, since it would seem to increase the size (if it has
-- any effect), but for ranges containing single value, or no
-- values, the high bound can be small too large. Consider:
-- type t is delta 2.0**(-14)
-- range 131072.0 .. 0;
-- That lower bound is *just* outside the range of 32 bits, and
-- does need fudging down in this case. Note that the bounds
-- will always have crossed here, since the high bound will be
-- fudged down if necessary, as in the case of:
-- type t is delta 2.0**(-14)
-- range 131072.0 .. 131072.0;
-- So we detect the situation by looking for crossed bounds,
-- and if the bounds are crossed, and the low bound is greater
-- than zero, we will always back it off by small, since this
-- is completely harmless.
if Actual_Lo > Actual_Hi then
if UR_Is_Positive (Actual_Lo) then
Actual_Lo := Loval_Incl_EP - Small;
Actual_Size := Fsize (Actual_Lo, Actual_Hi);
-- And of course, we need to do exactly the same parallel
-- fudge for flat ranges in the negative region.
elsif UR_Is_Negative (Actual_Hi) then
Actual_Hi := Hival_Incl_EP + Small;
Actual_Size := Fsize (Actual_Lo, Actual_Hi);
end if;
end if;
end if;
Set_Realval (Lo, Actual_Lo);
Set_Realval (Hi, Actual_Hi);
end Fudge;
-- For the decimal case, none of this fudging is required, since there
-- are no end-point problems in the decimal case (the end-points are
-- always included).
else
Actual_Size := Fsize (Loval, Hival);
end if;
-- At this stage, the actual size has been calculated and the proper
-- required bounds are stored in the low and high bounds.
if Actual_Size > 64 then
Error_Msg_Uint_1 := UI_From_Int (Actual_Size);
Error_Msg_N
("size required (^) for type& too large, maximum 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, Sloc (N));
if Is_Non_Empty_List (L) then
Insert_Actions (N, L);
end if;
end Freeze_Itype;
--------------------------
-- Freeze_Static_Object --
--------------------------
procedure Freeze_Static_Object (E : Entity_Id) is
Cannot_Be_Static : exception;
-- Exception raised if the type of a static object cannot be made
-- static. This happens if the type depends on non-global objects.
procedure Ensure_Expression_Is_SA (N : Node_Id);
-- Called to ensure that an expression used as part of a type definition
-- is statically allocatable, which means that the expression type is
-- statically allocatable, and the expression is either static, or a
-- reference to a library level constant.
procedure Ensure_Type_Is_SA (Typ : Entity_Id);
-- Called to mark a type as static, checking that it is possible
-- to set the type as static. If it is not possible, then the
-- exception Cannot_Be_Static is raised.
-----------------------------
-- Ensure_Expression_Is_SA --
-----------------------------
procedure Ensure_Expression_Is_SA (N : Node_Id) is
Ent : Entity_Id;
begin
Ensure_Type_Is_SA (Etype (N));
if Is_Static_Expression (N) then
return;
elsif Nkind (N) = N_Identifier then
Ent := Entity (N);
if Present (Ent)
and then Ekind (Ent) = E_Constant
and then Is_Library_Level_Entity (Ent)
then
return;
end if;
end if;
raise Cannot_Be_Static;
end Ensure_Expression_Is_SA;
-----------------------
-- Ensure_Type_Is_SA --
-----------------------
procedure Ensure_Type_Is_SA (Typ : Entity_Id) is
N : Node_Id;
C : Entity_Id;
begin
-- If type is library level, we are all set
if Is_Library_Level_Entity (Typ) then
return;
end if;
-- We are also OK if the type already marked as statically allocated,
-- which means we processed it before.
if Is_Statically_Allocated (Typ) then
return;
end if;
-- Mark type as statically allocated
Set_Is_Statically_Allocated (Typ);
-- Check that it is safe to statically allocate this type
if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then
Ensure_Expression_Is_SA (Type_Low_Bound (Typ));
Ensure_Expression_Is_SA (Type_High_Bound (Typ));
elsif Is_Array_Type (Typ) then
N := First_Index (Typ);
while Present (N) loop
Ensure_Type_Is_SA (Etype (N));
Next_Index (N);
end loop;
Ensure_Type_Is_SA (Component_Type (Typ));
elsif Is_Access_Type (Typ) then
if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then
declare
F : Entity_Id;
T : constant Entity_Id := Etype (Designated_Type (Typ));
begin
if T /= Standard_Void_Type then
Ensure_Type_Is_SA (T);
end if;
F := First_Formal (Designated_Type (Typ));
while Present (F) loop
Ensure_Type_Is_SA (Etype (F));
Next_Formal (F);
end loop;
end;
else
Ensure_Type_Is_SA (Designated_Type (Typ));
end if;
elsif Is_Record_Type (Typ) then
C := First_Entity (Typ);
while Present (C) loop
if Ekind (C) = E_Discriminant
or else Ekind (C) = E_Component
then
Ensure_Type_Is_SA (Etype (C));
elsif Is_Type (C) then
Ensure_Type_Is_SA (C);
end if;
Next_Entity (C);
end loop;
elsif Ekind (Typ) = E_Subprogram_Type then
Ensure_Type_Is_SA (Etype (Typ));
C := First_Formal (Typ);
while Present (C) loop
Ensure_Type_Is_SA (Etype (C));
Next_Formal (C);
end loop;
else
raise Cannot_Be_Static;
end if;
end Ensure_Type_Is_SA;
-- Start of processing for Freeze_Static_Object
begin
Ensure_Type_Is_SA (Etype (E));
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.
if Is_Imported (E) and then No (Address_Clause (E)) then
Error_Msg_N
("& cannot be imported (local type is not constant)", E);
-- Otherwise must be exported, something is wrong if compiler
-- is marking something as statically allocated which cannot be).
else pragma Assert (Is_Exported (E));
Error_Msg_N
("& cannot be exported (local type is not constant)", E);
end if;
end Freeze_Static_Object;
-----------------------
-- Freeze_Subprogram --
-----------------------
procedure Freeze_Subprogram (E : Entity_Id) is
Retype : Entity_Id;
F : Entity_Id;
begin
-- Subprogram may not have an address clause unless it is imported
if Present (Address_Clause (E)) then
if not Is_Imported (E) then
Error_Msg_N
("address clause can only be given " &
"for imported subprogram",
Name (Address_Clause (E)));
end if;
end if;
-- Reset the Pure indication on an imported subprogram unless an
-- explicit Pure_Function pragma was present. We do this because
-- otherwise it is an insidious error to call a non-pure function from
-- pure unit and have calls mysteriously optimized away. What happens
-- here is that the Import can bypass the normal check to ensure that
-- pure units call only pure subprograms.
if Is_Imported (E)
and then Is_Pure (E)
and then not Has_Pragma_Pure_Function (E)
then
Set_Is_Pure (E, False);
end if;
-- For non-foreign convention subprograms, this is where we create
-- the extra formals (for accessibility level and constrained bit
-- information). We delay this till the freeze point precisely so
-- that we know the convention!
if not Has_Foreign_Convention (E) then
Create_Extra_Formals (E);
Set_Mechanisms (E);
-- If this is convention Ada and a Valued_Procedure, that's odd
if Ekind (E) = E_Procedure
and then Is_Valued_Procedure (E)
and then Convention (E) = Convention_Ada
and then Warn_On_Export_Import
then
Error_Msg_N
("?Valued_Procedure has no effect for convention Ada", E);
Set_Is_Valued_Procedure (E, False);
end if;
-- Case of foreign convention
else
Set_Mechanisms (E);
-- For foreign conventions, warn about return of an
-- unconstrained array.
-- Note: we *do* allow a return by descriptor for the VMS case,
-- though here there is probably more to be done ???
if Ekind (E) = E_Function then
Retype := Underlying_Type (Etype (E));
-- If no return type, probably some other error, e.g. a
-- missing full declaration, so ignore.
if No (Retype) then
null;
-- If the return type is generic, we have emitted a warning
-- earlier on, and there is nothing else to check here. Specific
-- instantiations may lead to erroneous behavior.
elsif Is_Generic_Type (Etype (E)) then
null;
-- 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;
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_Defining_Identifier (Loc, New_Internal_Name ('D'));
Dbody :=
Make_Subprogram_Body (Loc,
Specification =>
Make_Procedure_Specification (Loc,
Defining_Unit_Name => Dnam),
Declarations => New_List (
Make_Object_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc,
New_Internal_Name ('T')),
Object_Definition =>
New_Occurrence_Of (Etype (Formal), Loc),
Expression => New_Copy_Tree (Dcopy))),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List));
Set_Scope (Dnam, Scope (E));
Set_Assignment_OK (First (Declarations (Dbody)));
Set_Is_Eliminated (Dnam);
Insert_After (After, Dbody);
Analyze (Dbody);
After := Dbody;
end if;
end if;
Next_Formal (Formal);
end loop;
end Process_Default_Expressions;
----------------------------------------
-- Set_Component_Alignment_If_Not_Set --
----------------------------------------
procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is
begin
-- Ignore if not base type, subtypes don't need anything
if Typ /= Base_Type (Typ) then
return;
end if;
-- Do not override existing representation
if Is_Packed (Typ) then
return;
elsif Has_Specified_Layout (Typ) then
return;
elsif Component_Alignment (Typ) /= Calign_Default then
return;
else
Set_Component_Alignment
(Typ, Scope_Stack.Table
(Scope_Stack.Last).Component_Alignment_Default);
end if;
end Set_Component_Alignment_If_Not_Set;
------------------
-- 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 Initialize_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).
if Present (Expr)
and then not Is_Imported (Ent)
and then (Has_Non_Null_Base_Init_Proc (Typ)
or else Is_Access_Type (Typ)
or else (Init_Or_Norm_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;
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