-- --
-- B o d y --
-- --
--- Copyright (C) 1992-2005 Free Software Foundation, Inc. --
+-- 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 2, or (at your option) any later ver- --
+-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
--- Public License distributed with GNAT; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
+-- Public License distributed with GNAT; see file COPYING3. If not, go to --
+-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
with Ada.Characters.Latin_1; use Ada.Characters.Latin_1;
with Atree; use Atree;
+with Casing; use Casing;
with Checks; use Checks;
with Einfo; use Einfo;
with Errout; use Errout;
with Eval_Fat;
+with Exp_Dist; use Exp_Dist;
with Exp_Util; use Exp_Util;
with Expander; use Expander;
with Freeze; use Freeze;
+with Gnatvsn; use Gnatvsn;
+with Itypes; use Itypes;
with Lib; use Lib;
with Lib.Xref; use Lib.Xref;
-with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Rtsfind; use Rtsfind;
with Sdefault; use Sdefault;
with Sem; use Sem;
+with Sem_Aux; use Sem_Aux;
with Sem_Cat; use Sem_Cat;
with Sem_Ch6; use Sem_Ch6;
with Sem_Ch8; use Sem_Ch8;
+with Sem_Ch10; use Sem_Ch10;
with Sem_Dist; use Sem_Dist;
+with Sem_Elim; use Sem_Elim;
with Sem_Eval; use Sem_Eval;
with Sem_Res; use Sem_Res;
with Sem_Type; use Sem_Type;
with Stand; use Stand;
with Sinfo; use Sinfo;
with Sinput; use Sinput;
-with Snames; use Snames;
-with Stand;
with Stringt; use Stringt;
+with Style;
+with Stylesw; use Stylesw;
with Targparm; use Targparm;
with Ttypes; use Ttypes;
with Ttypef; use Ttypef;
-- trouble with cascaded errors.
-- The following array is the list of attributes defined in the Ada 83 RM
+ -- that are not included in Ada 95, but still get recognized in GNAT.
Attribute_83 : constant Attribute_Class_Array := Attribute_Class_Array'(
Attribute_Address |
Attribute_Width => True,
others => False);
+ -- The following array is the list of attributes defined in the Ada 2005
+ -- RM which are not defined in Ada 95. These are recognized in Ada 95 mode,
+ -- but in Ada 95 they are considered to be implementation defined.
+
+ Attribute_05 : constant Attribute_Class_Array := Attribute_Class_Array'(
+ Attribute_Machine_Rounding |
+ Attribute_Priority |
+ Attribute_Stream_Size |
+ Attribute_Wide_Wide_Width => True,
+ others => False);
+
+ -- The following array contains all attributes that imply a modification
+ -- of their prefixes or result in an access value. Such prefixes can be
+ -- considered as lvalues.
+
+ Attribute_Name_Implies_Lvalue_Prefix : constant Attribute_Class_Array :=
+ Attribute_Class_Array'(
+ Attribute_Access |
+ Attribute_Address |
+ Attribute_Input |
+ Attribute_Read |
+ Attribute_Unchecked_Access |
+ Attribute_Unrestricted_Access => True,
+ others => False);
+
-----------------------
-- Local_Subprograms --
-----------------------
procedure Check_Dereference;
-- If the prefix of attribute is an object of an access type, then
- -- introduce an explicit deference, and adjust P_Type accordingly.
+ -- introduce an explicit dereference, and adjust P_Type accordingly.
procedure Check_Discrete_Type;
-- Verify that prefix of attribute N is a discrete type
procedure Check_Enum_Image;
-- If the prefix type is an enumeration type, set all its literals
-- as referenced, since the image function could possibly end up
- -- referencing any of the literals indirectly.
+ -- referencing any of the literals indirectly. Same for Enum_Val.
procedure Check_Fixed_Point_Type;
-- Verify that prefix of attribute N is a fixed type
-- two attribute expressions are present
procedure Legal_Formal_Attribute;
- -- Common processing for attributes Definite, Has_Access_Values,
- -- and Has_Discriminants
+ -- Common processing for attributes Definite and Has_Discriminants.
+ -- Checks that prefix is generic indefinite formal type.
procedure Check_Integer_Type;
-- Verify that prefix of attribute N is an integer type
procedure Check_Modular_Integer_Type;
-- Verify that prefix of attribute N is a modular integer type
+ procedure Check_Not_CPP_Type;
+ -- Check that P (the prefix of the attribute) is not an CPP type
+ -- for which no Ada predefined primitive is available.
+
procedure Check_Not_Incomplete_Type;
-- Check that P (the prefix of the attribute) is not an incomplete
-- type or a private type for which no full view has been given.
-- corresponding possible defined attribute function (e.g. for the
-- Read attribute, Nam will be TSS_Stream_Read).
+ procedure Check_PolyORB_Attribute;
+ -- Validity checking for PolyORB/DSA attribute
+
procedure Check_Task_Prefix;
-- Verify that prefix of attribute N is a task or task type
-- no arguments is used when the caller has already generated the
-- required error messages.
+ procedure Error_Attr_P (Msg : String);
+ pragma No_Return (Error_Attr);
+ -- Like Error_Attr, but error is posted at the start of the prefix
+
procedure Standard_Attribute (Val : Int);
-- Used to process attributes whose prefix is package Standard which
-- yield values of type Universal_Integer. The attribute reference
-- type that is constructed is returned as the result.
procedure Build_Access_Subprogram_Type (P : Node_Id);
- -- Build an access to subprogram whose designated type is
- -- the type of the prefix. If prefix is overloaded, so it the
- -- node itself. The result is stored in Acc_Type.
+ -- Build an access to subprogram whose designated type is the type of
+ -- the prefix. If prefix is overloaded, so is the node itself. The
+ -- result is stored in Acc_Type.
+
+ function OK_Self_Reference return Boolean;
+ -- An access reference whose prefix is a type can legally appear
+ -- within an aggregate, where it is obtained by expansion of
+ -- a defaulted aggregate. The enclosing aggregate that contains
+ -- the self-referenced is flagged so that the self-reference can
+ -- be expanded into a reference to the target object (see exp_aggr).
------------------------------
-- Build_Access_Object_Type --
------------------------------
function Build_Access_Object_Type (DT : Entity_Id) return Entity_Id is
- Typ : Entity_Id;
-
+ Typ : constant Entity_Id :=
+ New_Internal_Entity
+ (E_Access_Attribute_Type, Current_Scope, Loc, 'A');
begin
- if Aname = Name_Unrestricted_Access then
- Typ :=
- New_Internal_Entity
- (E_Allocator_Type, Current_Scope, Loc, 'A');
- else
- Typ :=
- New_Internal_Entity
- (E_Access_Attribute_Type, Current_Scope, Loc, 'A');
- end if;
-
Set_Etype (Typ, Typ);
- Init_Size_Align (Typ);
Set_Is_Itype (Typ);
Set_Associated_Node_For_Itype (Typ, N);
Set_Directly_Designated_Type (Typ, DT);
Index : Interp_Index;
It : Interp;
+ procedure Check_Local_Access (E : Entity_Id);
+ -- Deal with possible access to local subprogram. If we have such
+ -- an access, we set a flag to kill all tracked values on any call
+ -- because this access value may be passed around, and any called
+ -- code might use it to access a local procedure which clobbers a
+ -- tracked value. If the scope is a loop or block, indicate that
+ -- value tracking is disabled for the enclosing subprogram.
+
function Get_Kind (E : Entity_Id) return Entity_Kind;
-- Distinguish between access to regular/protected subprograms
+ ------------------------
+ -- Check_Local_Access --
+ ------------------------
+
+ procedure Check_Local_Access (E : Entity_Id) is
+ begin
+ if not Is_Library_Level_Entity (E) then
+ Set_Suppress_Value_Tracking_On_Call (Current_Scope);
+ Set_Suppress_Value_Tracking_On_Call
+ (Nearest_Dynamic_Scope (Current_Scope));
+ end if;
+ end Check_Local_Access;
+
--------------
-- Get_Kind --
--------------
-- subprogram itself as the designated type. Type-checking in
-- this case compares the signatures of the designated types.
+ -- Note: This fragment of the tree is temporarily malformed
+ -- because the correct tree requires an E_Subprogram_Type entity
+ -- as the designated type. In most cases this designated type is
+ -- later overridden by the semantics with the type imposed by the
+ -- context during the resolution phase. In the specific case of
+ -- the expression Address!(Prim'Unrestricted_Access), used to
+ -- initialize slots of dispatch tables, this work will be done by
+ -- the expander (see Exp_Aggr).
+
+ -- The reason to temporarily add this kind of node to the tree
+ -- instead of a proper E_Subprogram_Type itype, is the following:
+ -- in case of errors found in the source file we report better
+ -- error messages. For example, instead of generating the
+ -- following error:
+
+ -- "expected access to subprogram with profile
+ -- defined at line X"
+
+ -- we currently generate:
+
+ -- "expected access to function Z defined at line X"
+
Set_Etype (N, Any_Type);
if not Is_Overloaded (P) then
+ Check_Local_Access (Entity (P));
+
if not Is_Intrinsic_Subprogram (Entity (P)) then
- Acc_Type :=
- New_Internal_Entity
- (Get_Kind (Entity (P)), Current_Scope, Loc, 'A');
+ Acc_Type := Create_Itype (Get_Kind (Entity (P)), N);
+ Set_Is_Public (Acc_Type, False);
Set_Etype (Acc_Type, Acc_Type);
+ Set_Convention (Acc_Type, Convention (Entity (P)));
Set_Directly_Designated_Type (Acc_Type, Entity (P));
Set_Etype (N, Acc_Type);
+ Freeze_Before (N, Acc_Type);
end if;
else
Get_First_Interp (P, Index, It);
while Present (It.Nam) loop
+ Check_Local_Access (It.Nam);
+
if not Is_Intrinsic_Subprogram (It.Nam) then
- Acc_Type :=
- New_Internal_Entity
- (Get_Kind (It.Nam), Current_Scope, Loc, 'A');
+ Acc_Type := Create_Itype (Get_Kind (It.Nam), N);
+ Set_Is_Public (Acc_Type, False);
Set_Etype (Acc_Type, Acc_Type);
+ Set_Convention (Acc_Type, Convention (It.Nam));
Set_Directly_Designated_Type (Acc_Type, It.Nam);
Add_One_Interp (N, Acc_Type, Acc_Type);
+ Freeze_Before (N, Acc_Type);
end if;
Get_Next_Interp (Index, It);
end loop;
end if;
+ -- Cannot be applied to intrinsic. Looking at the tests above,
+ -- the only way Etype (N) can still be set to Any_Type is if
+ -- Is_Intrinsic_Subprogram was True for some referenced entity.
+
if Etype (N) = Any_Type then
- Error_Attr ("prefix of % attribute cannot be intrinsic", P);
+ Error_Attr_P ("prefix of % attribute cannot be intrinsic");
end if;
end Build_Access_Subprogram_Type;
+ ----------------------
+ -- OK_Self_Reference --
+ ----------------------
+
+ function OK_Self_Reference return Boolean is
+ Par : Node_Id;
+
+ begin
+ Par := Parent (N);
+ while Present (Par)
+ and then
+ (Nkind (Par) = N_Component_Association
+ or else Nkind (Par) in N_Subexpr)
+ loop
+ if Nkind_In (Par, N_Aggregate, N_Extension_Aggregate) then
+ if Etype (Par) = Typ then
+ Set_Has_Self_Reference (Par);
+ return True;
+ end if;
+ end if;
+
+ Par := Parent (Par);
+ end loop;
+
+ -- No enclosing aggregate, or not a self-reference
+
+ return False;
+ end OK_Self_Reference;
+
-- Start of processing for Analyze_Access_Attribute
begin
Check_E0;
if Nkind (P) = N_Character_Literal then
- Error_Attr
- ("prefix of % attribute cannot be enumeration literal", P);
+ Error_Attr_P
+ ("prefix of % attribute cannot be enumeration literal");
end if;
-- Case of access to subprogram
if Is_Entity_Name (P)
and then Is_Overloadable (Entity (P))
then
- -- Not allowed for nested subprograms if No_Implicit_Dynamic_Code
- -- restriction set (since in general a trampoline is required).
-
- if not Is_Library_Level_Entity (Entity (P)) then
- Check_Restriction (No_Implicit_Dynamic_Code, P);
+ if Has_Pragma_Inline_Always (Entity (P)) then
+ Error_Attr_P
+ ("prefix of % attribute cannot be Inline_Always subprogram");
end if;
- if Is_Always_Inlined (Entity (P)) then
- Error_Attr
- ("prefix of % attribute cannot be Inline_Always subprogram",
- P);
+ if Aname = Name_Unchecked_Access then
+ Error_Attr ("attribute% cannot be applied to a subprogram", P);
end if;
+ -- Issue an error if the prefix denotes an eliminated subprogram
+
+ Check_For_Eliminated_Subprogram (P, Entity (P));
+
-- Build the appropriate subprogram type
Build_Access_Subprogram_Type (P);
-- could modify local variables to be passed out of scope
if Aname = Name_Unrestricted_Access then
- Kill_Current_Values;
+
+ -- Do not kill values on nodes initializing dispatch tables
+ -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
+ -- is currently generated by the expander only for this
+ -- purpose. Done to keep the quality of warnings currently
+ -- generated by the compiler (otherwise any declaration of
+ -- a tagged type cleans constant indications from its scope).
+
+ if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
+ and then (Etype (Parent (N)) = RTE (RE_Prim_Ptr)
+ or else
+ Etype (Parent (N)) = RTE (RE_Size_Ptr))
+ and then Is_Dispatching_Operation
+ (Directly_Designated_Type (Etype (N)))
+ then
+ null;
+ else
+ Kill_Current_Values;
+ end if;
end if;
return;
and then Is_Overloadable (Entity (Selector_Name (P)))
then
if Ekind (Entity (Selector_Name (P))) = E_Entry then
- Error_Attr ("prefix of % attribute must be subprogram", P);
+ Error_Attr_P ("prefix of % attribute must be subprogram");
end if;
Build_Access_Subprogram_Type (Selector_Name (P));
end if;
-- Deal with incorrect reference to a type, but note that some
- -- accesses are allowed (references to the current type instance).
+ -- accesses are allowed: references to the current type instance,
+ -- or in Ada 2005 self-referential pointer in a default-initialized
+ -- aggregate.
if Is_Entity_Name (P) then
- Scop := Current_Scope;
Typ := Entity (P);
+ -- The reference may appear in an aggregate that has been expanded
+ -- into a loop. Locate scope of type definition, if any.
+
+ Scop := Current_Scope;
+ while Ekind (Scop) = E_Loop loop
+ Scop := Scope (Scop);
+ end loop;
+
if Is_Type (Typ) then
-- OK if we are within the scope of a limited type
loop
Q := Parent (Q);
end loop;
+
if Present (Q) then
- Set_Has_Per_Object_Constraint (
- Defining_Identifier (Q), True);
+ Set_Has_Per_Object_Constraint
+ (Defining_Identifier (Q), True);
end if;
end;
if Nkind (P) = N_Expanded_Name then
- Error_Msg_N
+ Error_Msg_F
("current instance prefix must be a direct name", P);
end if;
- -- If a current instance attribute appears within a
- -- a component constraint it must appear alone; other
- -- contexts (default expressions, within a task body)
- -- are not subject to this restriction.
+ -- If a current instance attribute appears in a component
+ -- constraint it must appear alone; other contexts (spec-
+ -- expressions, within a task body) are not subject to this
+ -- restriction.
- if not In_Default_Expression
+ if not In_Spec_Expression
and then not Has_Completion (Scop)
- and then
- Nkind (Parent (N)) /= N_Discriminant_Association
- and then
- Nkind (Parent (N)) /= N_Index_Or_Discriminant_Constraint
+ and then not
+ Nkind_In (Parent (N), N_Discriminant_Association,
+ N_Index_Or_Discriminant_Constraint)
then
Error_Msg_N
("current instance attribute must appear alone", N);
elsif Is_Task_Type (Typ) then
null;
+ -- OK if self-reference in an aggregate in Ada 2005, and
+ -- the reference comes from a copied default expression.
+
+ -- Note that we check legality of self-reference even if the
+ -- expression comes from source, e.g. when a single component
+ -- association in an aggregate has a box association.
+
+ elsif Ada_Version >= Ada_05
+ and then OK_Self_Reference
+ then
+ null;
+
+ -- OK if reference to current instance of a protected object
+
+ elsif Is_Protected_Self_Reference (P) then
+ null;
+
-- Otherwise we have an error case
else
declare
Index : Interp_Index;
It : Interp;
-
begin
Set_Etype (N, Any_Type);
Get_First_Interp (P, Index, It);
-
while Present (It.Typ) loop
Acc_Type := Build_Access_Object_Type (It.Typ);
Add_One_Interp (N, Acc_Type, Acc_Type);
end;
end if;
- -- If we have an access to an object, and the attribute comes
- -- from source, then set the object as potentially source modified.
- -- We do this because the resulting access pointer can be used to
- -- modify the variable, and we might not detect this, leading to
- -- some junk warnings.
+ -- Special cases when we can find a prefix that is an entity name
- if Is_Entity_Name (P) then
- Set_Never_Set_In_Source (Entity (P), False);
- end if;
+ declare
+ PP : Node_Id;
+ Ent : Entity_Id;
+
+ begin
+ PP := P;
+ loop
+ if Is_Entity_Name (PP) then
+ Ent := Entity (PP);
- -- Check for aliased view unless unrestricted case. We allow
- -- a nonaliased prefix when within an instance because the
- -- prefix may have been a tagged formal object, which is
- -- defined to be aliased even when the actual might not be
- -- (other instance cases will have been caught in the generic).
- -- Similarly, within an inlined body we know that the attribute
- -- is legal in the original subprogram, and therefore legal in
- -- the expansion.
+ -- If we have an access to an object, and the attribute
+ -- comes from source, then set the object as potentially
+ -- source modified. We do this because the resulting access
+ -- pointer can be used to modify the variable, and we might
+ -- not detect this, leading to some junk warnings.
+
+ Set_Never_Set_In_Source (Ent, False);
+
+ -- Mark entity as address taken, and kill current values
+
+ Set_Address_Taken (Ent);
+ Kill_Current_Values (Ent);
+ exit;
+
+ elsif Nkind_In (PP, N_Selected_Component,
+ N_Indexed_Component)
+ then
+ PP := Prefix (PP);
+
+ else
+ exit;
+ end if;
+ end loop;
+ end;
+
+ -- Check for aliased view unless unrestricted case. We allow a
+ -- nonaliased prefix when within an instance because the prefix may
+ -- have been a tagged formal object, which is defined to be aliased
+ -- even when the actual might not be (other instance cases will have
+ -- been caught in the generic). Similarly, within an inlined body we
+ -- know that the attribute is legal in the original subprogram, and
+ -- therefore legal in the expansion.
if Aname /= Name_Unrestricted_Access
and then not Is_Aliased_View (P)
and then not In_Instance
and then not In_Inlined_Body
then
- Error_Attr ("prefix of % attribute must be aliased", P);
+ Error_Attr_P ("prefix of % attribute must be aliased");
end if;
end Analyze_Access_Attribute;
-- recovery behavior.
Error_Msg_Name_1 := Aname;
- Error_Msg_N
+ Error_Msg_F
("prefix for % attribute must be constrained array", P);
end if;
else
if Is_Private_Type (P_Type) then
- Error_Attr
- ("prefix for % attribute may not be private type", P);
+ Error_Attr_P ("prefix for % attribute may not be private type");
elsif Is_Access_Type (P_Type)
and then Is_Array_Type (Designated_Type (P_Type))
and then Is_Entity_Name (P)
and then Is_Type (Entity (P))
then
- Error_Attr ("prefix of % attribute cannot be access type", P);
+ Error_Attr_P ("prefix of % attribute cannot be access type");
elsif Attr_Id = Attribute_First
or else
Error_Attr ("invalid prefix for % attribute", P);
else
- Error_Attr ("prefix for % attribute must be array", P);
+ Error_Attr_P ("prefix for % attribute must be array");
end if;
end if;
Error_Attr ("invalid dimension number for array type", E1);
end if;
end if;
+
+ if (Style_Check and Style_Check_Array_Attribute_Index)
+ and then Comes_From_Source (N)
+ then
+ Style.Check_Array_Attribute_Index (N, E1, D);
+ end if;
end Check_Array_Type;
-------------------------
and then
Ekind (Entity (Selector_Name (P))) /= E_Discriminant)
then
- Error_Attr
- ("prefix for % attribute must be selected component", P);
+ Error_Attr_P ("prefix for % attribute must be selected component");
end if;
end Check_Component;
Check_Type;
if not Is_Decimal_Fixed_Point_Type (P_Type) then
- Error_Attr
- ("prefix of % attribute must be decimal type", P);
+ Error_Attr_P ("prefix of % attribute must be decimal type");
end if;
end Check_Decimal_Fixed_Point_Type;
-- the designated type of the access type, since the type of
-- the referenced array is this type (see AI95-00106).
- Freeze_Before (N, Designated_Type (P_Type));
+ -- As done elsewhere, freezing must not happen when pre-analyzing
+ -- a pre- or postcondition or a default value for an object or
+ -- for a formal parameter.
+
+ if not In_Spec_Expression then
+ Freeze_Before (N, Designated_Type (P_Type));
+ end if;
Rewrite (P,
Make_Explicit_Dereference (Sloc (P),
Check_Type;
if not Is_Discrete_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be discrete type", P);
+ Error_Attr_P ("prefix of % attribute must be discrete type");
end if;
end Check_Discrete_Type;
procedure Check_Enum_Image is
Lit : Entity_Id;
-
begin
if Is_Enumeration_Type (P_Base_Type) then
Lit := First_Literal (P_Base_Type);
Check_Type;
if not Is_Fixed_Point_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be fixed point type", P);
+ Error_Attr_P ("prefix of % attribute must be fixed point type");
end if;
end Check_Fixed_Point_Type;
Check_Type;
if not Is_Floating_Point_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be float type", P);
+ Error_Attr_P ("prefix of % attribute must be float type");
end if;
end Check_Floating_Point_Type;
Check_Type;
if not Is_Integer_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be integer type", P);
+ Error_Attr_P ("prefix of % attribute must be integer type");
end if;
end Check_Integer_Type;
procedure Check_Library_Unit is
begin
if not Is_Compilation_Unit (Entity (P)) then
- Error_Attr ("prefix of % attribute must be library unit", P);
+ Error_Attr_P ("prefix of % attribute must be library unit");
end if;
end Check_Library_Unit;
Check_Type;
if not Is_Modular_Integer_Type (P_Type) then
- Error_Attr
- ("prefix of % attribute must be modular integer type", P);
+ Error_Attr_P
+ ("prefix of % attribute must be modular integer type");
end if;
end Check_Modular_Integer_Type;
+ ------------------------
+ -- Check_Not_CPP_Type --
+ ------------------------
+
+ procedure Check_Not_CPP_Type is
+ begin
+ if Is_Tagged_Type (Etype (P))
+ and then Convention (Etype (P)) = Convention_CPP
+ and then Is_CPP_Class (Root_Type (Etype (P)))
+ then
+ Error_Attr_P
+ ("invalid use of % attribute with 'C'P'P tagged type");
+ end if;
+ end Check_Not_CPP_Type;
+
-------------------------------
-- Check_Not_Incomplete_Type --
-------------------------------
procedure Check_Not_Incomplete_Type is
+ E : Entity_Id;
+ Typ : Entity_Id;
+
begin
+ -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
+ -- dereference we have to check wrong uses of incomplete types
+ -- (other wrong uses are checked at their freezing point).
+
+ -- Example 1: Limited-with
+
+ -- limited with Pkg;
+ -- package P is
+ -- type Acc is access Pkg.T;
+ -- X : Acc;
+ -- S : Integer := X.all'Size; -- ERROR
+ -- end P;
+
+ -- Example 2: Tagged incomplete
+
+ -- type T is tagged;
+ -- type Acc is access all T;
+ -- X : Acc;
+ -- S : constant Integer := X.all'Size; -- ERROR
+ -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
+
+ if Ada_Version >= Ada_05
+ and then Nkind (P) = N_Explicit_Dereference
+ then
+ E := P;
+ while Nkind (E) = N_Explicit_Dereference loop
+ E := Prefix (E);
+ end loop;
+
+ Typ := Etype (E);
+
+ if From_With_Type (Typ) then
+ Error_Attr_P
+ ("prefix of % attribute cannot be an incomplete type");
+
+ else
+ if Is_Access_Type (Typ) then
+ Typ := Directly_Designated_Type (Typ);
+ end if;
+
+ if Is_Class_Wide_Type (Typ) then
+ Typ := Root_Type (Typ);
+ end if;
+
+ -- A legal use of a shadow entity occurs only when the unit
+ -- where the non-limited view resides is imported via a regular
+ -- with clause in the current body. Such references to shadow
+ -- entities may occur in subprogram formals.
+
+ if Is_Incomplete_Type (Typ)
+ and then From_With_Type (Typ)
+ and then Present (Non_Limited_View (Typ))
+ and then Is_Legal_Shadow_Entity_In_Body (Typ)
+ then
+ Typ := Non_Limited_View (Typ);
+ end if;
+
+ if Ekind (Typ) = E_Incomplete_Type
+ and then No (Full_View (Typ))
+ then
+ Error_Attr_P
+ ("prefix of % attribute cannot be an incomplete type");
+ end if;
+ end if;
+ end if;
+
if not Is_Entity_Name (P)
or else not Is_Type (Entity (P))
- or else In_Default_Expression
+ or else In_Spec_Expression
then
return;
-
else
Check_Fully_Declared (P_Type, P);
end if;
-- Otherwise we must have an object reference
elsif not Is_Object_Reference (P) then
- Error_Attr ("prefix of % attribute must be object", P);
+ Error_Attr_P ("prefix of % attribute must be object");
end if;
end Check_Object_Reference;
+ ----------------------------
+ -- Check_PolyORB_Attribute --
+ ----------------------------
+
+ procedure Check_PolyORB_Attribute is
+ begin
+ Validate_Non_Static_Attribute_Function_Call;
+
+ Check_Type;
+ Check_Not_CPP_Type;
+
+ if Get_PCS_Name /= Name_PolyORB_DSA then
+ Error_Attr
+ ("attribute% requires the 'Poly'O'R'B 'P'C'S", N);
+ end if;
+ end Check_PolyORB_Attribute;
+
------------------------
-- Check_Program_Unit --
------------------------
end;
end if;
- Error_Attr ("prefix of % attribute must be program unit", P);
+ Error_Attr_P ("prefix of % attribute must be program unit");
end Check_Program_Unit;
---------------------
Check_Type;
if not Is_Real_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be real type", P);
+ Error_Attr_P ("prefix of % attribute must be real type");
end if;
end Check_Real_Type;
Check_Type;
if not Is_Scalar_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be scalar type", P);
+ Error_Attr_P ("prefix of % attribute must be scalar type");
end if;
end Check_Scalar_Type;
then
Error_Attr ("only allowed prefix for % attribute is Standard", P);
end if;
-
end Check_Standard_Prefix;
----------------------------
procedure Check_Stream_Attribute (Nam : TSS_Name_Type) is
Etyp : Entity_Id;
Btyp : Entity_Id;
+
+ In_Shared_Var_Procs : Boolean;
+ -- True when compiling the body of System.Shared_Storage.
+ -- Shared_Var_Procs. For this runtime package (always compiled in
+ -- GNAT mode), we allow stream attributes references for limited
+ -- types for the case where shared passive objects are implemented
+ -- using stream attributes, which is the default in GNAT's persistent
+ -- storage implementation.
+
begin
Validate_Non_Static_Attribute_Function_Call;
null;
elsif Is_List_Member (N)
- and then Nkind (Parent (N)) /= N_Procedure_Call_Statement
- and then Nkind (Parent (N)) /= N_Aggregate
+ and then not Nkind_In (Parent (N), N_Procedure_Call_Statement,
+ N_Aggregate)
then
null;
-- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
-- (with no visibility restriction).
- if Comes_From_Source (N)
+ declare
+ Gen_Body : constant Node_Id := Enclosing_Generic_Body (N);
+ begin
+ if Present (Gen_Body) then
+ In_Shared_Var_Procs :=
+ Is_RTE (Corresponding_Spec (Gen_Body), RE_Shared_Var_Procs);
+ else
+ In_Shared_Var_Procs := False;
+ end if;
+ end;
+
+ if (Comes_From_Source (N)
+ and then not (In_Shared_Var_Procs or In_Instance))
and then not Stream_Attribute_Available (P_Type, Nam)
and then not Has_Rep_Pragma (Btyp, Name_Stream_Convert)
then
end if;
end if;
- -- Check for violation of restriction No_Stream_Attributes
+ -- Check restriction violations
+
+ -- First check the No_Streams restriction, which prohibits the use
+ -- of explicit stream attributes in the source program. We do not
+ -- prevent the occurrence of stream attributes in generated code,
+ -- for instance those generated implicitly for dispatching purposes.
+
+ if Comes_From_Source (N) then
+ Check_Restriction (No_Streams, P);
+ end if;
+
+ -- Check special case of Exception_Id and Exception_Occurrence which
+ -- are not allowed for restriction No_Exception_Regstriation.
if Is_RTE (P_Type, RE_Exception_Id)
or else
-- Note: the double call to Root_Type here is needed because the
-- root type of a class-wide type is the corresponding type (e.g.
- -- X for X'Class, and we really want to go to the root.
+ -- X for X'Class, and we really want to go to the root.)
if not Is_Access_Type (Etyp)
or else Root_Type (Root_Type (Designated_Type (Etyp))) /=
Resolve (E2, P_Type);
end if;
+
+ Check_Not_CPP_Type;
end Check_Stream_Attribute;
-----------------------
begin
Analyze (P);
+ -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
+ -- task interface class-wide types.
+
if Is_Task_Type (Etype (P))
or else (Is_Access_Type (Etype (P))
- and then Is_Task_Type (Designated_Type (Etype (P))))
+ and then Is_Task_Type (Designated_Type (Etype (P))))
+ or else (Ada_Version >= Ada_05
+ and then Ekind (Etype (P)) = E_Class_Wide_Type
+ and then Is_Interface (Etype (P))
+ and then Is_Task_Interface (Etype (P)))
then
Resolve (P);
+
else
- Error_Attr ("prefix of % attribute must be a task", P);
+ if Ada_Version >= Ada_05 then
+ Error_Attr_P
+ ("prefix of % attribute must be a task or a task " &
+ "interface class-wide object");
+
+ else
+ Error_Attr_P ("prefix of % attribute must be a task");
+ end if;
end if;
end Check_Task_Prefix;
if not Is_Entity_Name (P)
or else not Is_Type (Entity (P))
then
- Error_Attr ("prefix of % attribute must be a type", P);
+ Error_Attr_P ("prefix of % attribute must be a type");
+
+ elsif Is_Protected_Self_Reference (P) then
+ Error_Attr_P
+ ("prefix of % attribute denotes current instance "
+ & "(RM 9.4(21/2))");
elsif Ekind (Entity (P)) = E_Incomplete_Type
and then Present (Full_View (Entity (P)))
Error_Attr;
end Error_Attr;
+ ------------------
+ -- Error_Attr_P --
+ ------------------
+
+ procedure Error_Attr_P (Msg : String) is
+ begin
+ Error_Msg_Name_1 := Aname;
+ Error_Msg_F (Msg, P);
+ Error_Attr;
+ end Error_Attr_P;
+
----------------------------
-- Legal_Formal_Attribute --
----------------------------
if not Is_Entity_Name (P)
or else not Is_Type (Entity (P))
then
- Error_Attr ("prefix of % attribute must be generic type", N);
+ Error_Attr_P ("prefix of % attribute must be generic type");
elsif Is_Generic_Actual_Type (Entity (P))
or else In_Instance
elsif Is_Generic_Type (Entity (P)) then
if not Is_Indefinite_Subtype (Entity (P)) then
- Error_Attr
- ("prefix of % attribute must be indefinite generic type", N);
+ Error_Attr_P
+ ("prefix of % attribute must be indefinite generic type");
end if;
else
- Error_Attr
- ("prefix of % attribute must be indefinite generic type", N);
+ Error_Attr_P
+ ("prefix of % attribute must be indefinite generic type");
end if;
Set_Etype (N, Standard_Boolean);
procedure Standard_Attribute (Val : Int) is
begin
Check_Standard_Prefix;
-
- -- First a special check (more like a kludge really). For GNAT5
- -- on Windows, the alignments in GCC are severely mixed up. In
- -- particular, we have a situation where the maximum alignment
- -- that GCC thinks is possible is greater than the guaranteed
- -- alignment at run-time. That causes many problems. As a partial
- -- cure for this situation, we force a value of 4 for the maximum
- -- alignment attribute on this target. This still does not solve
- -- all problems, but it helps.
-
- -- A further (even more horrible) dimension to this kludge is now
- -- installed. There are two uses for Maximum_Alignment, one is to
- -- determine the maximum guaranteed alignment, that's the one we
- -- want the kludge to yield as 4. The other use is to maximally
- -- align objects, we can't use 4 here, since for example, long
- -- long integer has an alignment of 8, so we will get errors.
-
- -- It is of course impossible to determine which use the programmer
- -- has in mind, but an approximation for now is to disconnect the
- -- kludge if the attribute appears in an alignment clause.
-
- -- To be removed if GCC ever gets its act together here ???
-
- Alignment_Kludge : declare
- P : Node_Id;
-
- function On_X86 return Boolean;
- -- Determine if target is x86 (ia32), return True if so
-
- ------------
- -- On_X86 --
- ------------
-
- function On_X86 return Boolean is
- T : constant String := Sdefault.Target_Name.all;
-
- begin
- -- There is no clean way to check this. That's not surprising,
- -- the front end should not be doing this kind of test ???. The
- -- way we do it is test for either "86" or "pentium" being in
- -- the string for the target name. However, we need to exclude
- -- x86_64 for this check.
-
- for J in T'First .. T'Last - 1 loop
- if (T (J .. J + 1) = "86"
- and then
- (J + 4 > T'Last
- or else T (J + 2 .. J + 4) /= "_64"))
- or else (J <= T'Last - 6
- and then T (J .. J + 6) = "pentium")
- then
- return True;
- end if;
- end loop;
-
- return False;
- end On_X86;
-
- begin
- if Aname = Name_Maximum_Alignment and then On_X86 then
- P := Parent (N);
-
- while Nkind (P) in N_Subexpr loop
- P := Parent (P);
- end loop;
-
- if Nkind (P) /= N_Attribute_Definition_Clause
- or else Chars (P) /= Name_Alignment
- then
- Rewrite (N, Make_Integer_Literal (Loc, 4));
- Analyze (N);
- return;
- end if;
- end if;
- end Alignment_Kludge;
-
- -- Normally we get the value from gcc ???
-
Rewrite (N, Make_Integer_Literal (Loc, Val));
Analyze (N);
end Standard_Attribute;
raise Bad_Attribute;
end if;
- -- Deal with Ada 83 and Features issues
+ -- Deal with Ada 83 issues
if Comes_From_Source (N) then
if not Attribute_83 (Attr_Id) then
end if;
end if;
+ -- Deal with Ada 2005 issues
+
+ if Attribute_05 (Attr_Id) and then Ada_Version <= Ada_95 then
+ Check_Restriction (No_Implementation_Attributes, N);
+ end if;
+
-- Remote access to subprogram type access attribute reference needs
-- unanalyzed copy for tree transformation. The analyzed copy is used
-- for its semantic information (whether prefix is a remote subprogram
end if;
-- Analyze prefix and exit if error in analysis. If the prefix is an
- -- incomplete type, use full view if available. A special case is
- -- that we never analyze the prefix of an Elab_Body or Elab_Spec
- -- or UET_Address attribute.
+ -- incomplete type, use full view if available. Note that there are
+ -- some attributes for which we do not analyze the prefix, since the
+ -- prefix is not a normal name.
if Aname /= Name_Elab_Body
and then
Aname /= Name_Elab_Spec
and then
Aname /= Name_UET_Address
+ and then
+ Aname /= Name_Enabled
then
Analyze (P);
P_Type := Etype (P);
if Is_Entity_Name (P)
and then Present (Entity (P))
and then Is_Type (Entity (P))
- and then Ekind (Entity (P)) = E_Incomplete_Type
then
- P_Type := Get_Full_View (P_Type);
- Set_Entity (P, P_Type);
- Set_Etype (P, P_Type);
+ if Ekind (Entity (P)) = E_Incomplete_Type then
+ P_Type := Get_Full_View (P_Type);
+ Set_Entity (P, P_Type);
+ Set_Etype (P, P_Type);
+
+ elsif Entity (P) = Current_Scope
+ and then Is_Record_Type (Entity (P))
+ then
+ -- Use of current instance within the type. Verify that if the
+ -- attribute appears within a constraint, it yields an access
+ -- type, other uses are illegal.
+
+ declare
+ Par : Node_Id;
+
+ begin
+ Par := Parent (N);
+ while Present (Par)
+ and then Nkind (Parent (Par)) /= N_Component_Definition
+ loop
+ Par := Parent (Par);
+ end loop;
+
+ if Present (Par)
+ and then Nkind (Par) = N_Subtype_Indication
+ then
+ if Attr_Id /= Attribute_Access
+ and then Attr_Id /= Attribute_Unchecked_Access
+ and then Attr_Id /= Attribute_Unrestricted_Access
+ then
+ Error_Msg_N
+ ("in a constraint the current instance can only"
+ & " be used with an access attribute", N);
+ end if;
+ end if;
+ end;
+ end if;
end if;
if P_Type = Any_Type then
E1 := First (Exprs);
Analyze (E1);
- -- Check for missing or bad expression (result of previous error)
+ -- Check for missing/bad expression (result of previous error)
if No (E1) or else Etype (E1) = Any_Type then
raise Bad_Attribute;
end if;
-- Ada 2005 (AI-345): Ensure that the compiler gives exactly the current
- -- output compiling in Ada 95 mode
+ -- output compiling in Ada 95 mode for the case of ambiguous prefixes.
if Ada_Version < Ada_05
and then Is_Overloaded (P)
and then Aname /= Name_Address
and then Aname /= Name_Code_Address
and then Aname /= Name_Count
+ and then Aname /= Name_Result
and then Aname /= Name_Unchecked_Access
then
Error_Attr ("ambiguous prefix for % attribute", P);
and then Aname /= Name_Access
and then Aname /= Name_Address
and then Aname /= Name_Code_Address
+ and then Aname /= Name_Result
and then Aname /= Name_Unchecked_Access
then
-- Ada 2005 (AI-345): Since protected and task types have primitive
begin
Get_First_Interp (P, I, It);
-
while Present (It.Nam) loop
if Comes_From_Source (It.Nam) then
Count := Count + 1;
-- An Address attribute created by expansion is legal even when it
-- applies to other entity-denoting expressions.
- if Is_Entity_Name (P) then
+ if Is_Protected_Self_Reference (P) then
+
+ -- Address attribute on a protected object self reference is legal
+
+ null;
+
+ elsif Is_Entity_Name (P) then
declare
Ent : constant Entity_Id := Entity (P);
begin
if Is_Subprogram (Ent) then
- if not Is_Library_Level_Entity (Ent) then
- Check_Restriction (No_Implicit_Dynamic_Code, P);
- end if;
-
Set_Address_Taken (Ent);
+ Kill_Current_Values (Ent);
- -- An Address attribute is accepted when generated by
- -- the compiler for dispatching operation, and an error
- -- is issued once the subprogram is frozen (to avoid
- -- confusing errors about implicit uses of Address in
- -- the dispatch table initialization).
+ -- An Address attribute is accepted when generated by the
+ -- compiler for dispatching operation, and an error is
+ -- issued once the subprogram is frozen (to avoid confusing
+ -- errors about implicit uses of Address in the dispatch
+ -- table initialization).
- if Is_Always_Inlined (Entity (P))
+ if Has_Pragma_Inline_Always (Entity (P))
and then Comes_From_Source (P)
then
- Error_Attr
+ Error_Attr_P
("prefix of % attribute cannot be Inline_Always" &
- " subprogram", P);
+ " subprogram");
+
+ -- It is illegal to apply 'Address to an intrinsic
+ -- subprogram. This is now formalized in AI05-0095.
+ -- In an instance, an attempt to obtain 'Address of an
+ -- intrinsic subprogram (e.g the renaming of a predefined
+ -- operator that is an actual) raises Program_Error.
+
+ elsif Convention (Ent) = Convention_Intrinsic then
+ if In_Instance then
+ Rewrite (N,
+ Make_Raise_Program_Error (Loc,
+ Reason => PE_Address_Of_Intrinsic));
+
+ else
+ Error_Msg_N
+ ("cannot take Address of intrinsic subprogram", N);
+ end if;
+
+ -- Issue an error if prefix denotes an eliminated subprogram
+
+ else
+ Check_For_Eliminated_Subprogram (P, Ent);
end if;
elsif Is_Object (Ent)
Check_E0;
Check_Not_Incomplete_Type;
+ Check_Not_CPP_Type;
Set_Etype (N, Universal_Integer);
---------------
end if;
end if;
- Note_Possible_Modification (E2);
+ Note_Possible_Modification (E2, Sure => True);
Set_Etype (N, RTE (RE_Asm_Output_Operand));
---------------
-- is set True for the entry family case). In the True case,
-- makes sure that Is_AST_Entry is set on the entry.
+ -------------------
+ -- Bad_AST_Entry --
+ -------------------
+
procedure Bad_AST_Entry is
begin
- Error_Attr ("prefix for % attribute must be task entry", P);
+ Error_Attr_P ("prefix for % attribute must be task entry");
end Bad_AST_Entry;
+ --------------
+ -- OK_Entry --
+ --------------
+
function OK_Entry (E : Entity_Id) return Boolean is
Result : Boolean;
if Result then
if not Is_AST_Entry (E) then
Error_Msg_Name_2 := Aname;
- Error_Attr
- ("% attribute requires previous % pragma", P);
+ Error_Attr ("% attribute requires previous % pragma", P);
end if;
end if;
-- or of a variable of the enclosing task type.
else
- if Nkind (Pref) = N_Identifier
- or else Nkind (Pref) = N_Expanded_Name
- then
+ if Nkind_In (Pref, N_Identifier, N_Expanded_Name) then
Ent := Entity (Pref);
if not OK_Entry (Ent)
Typ : Entity_Id;
begin
- Check_Either_E0_Or_E1;
+ Check_E0;
Find_Type (P);
Typ := Entity (P);
and then not Is_Scalar_Type (Typ)
and then not Is_Generic_Type (Typ)
then
- Error_Msg_N ("prefix of Base attribute must be scalar type", N);
+ Error_Attr_P ("prefix of Base attribute must be scalar type");
elsif Sloc (Typ) = Standard_Location
and then Base_Type (Typ) = Typ
and then Warn_On_Redundant_Constructs
then
- Error_Msg_NE
- ("?redudant attribute, & is its own base type", N, Typ);
+ Error_Msg_NE
+ ("?redundant attribute, & is its own base type", N, Typ);
end if;
Set_Etype (N, Base_Type (Entity (P)));
-
- -- If we have an expression present, then really this is a conversion
- -- and the tree must be reformed. Note that this is one of the cases
- -- in which we do a replace rather than a rewrite, because the
- -- original tree is junk.
-
- if Present (E1) then
- Replace (N,
- Make_Type_Conversion (Loc,
- Subtype_Mark =>
- Make_Attribute_Reference (Loc,
- Prefix => Prefix (N),
- Attribute_Name => Name_Base),
- Expression => Relocate_Node (E1)));
-
- -- E1 may be overloaded, and its interpretations preserved
-
- Save_Interps (E1, Expression (N));
- Analyze (N);
-
- -- For other cases, set the proper type as the entity of the
- -- attribute reference, and then rewrite the node to be an
- -- occurrence of the referenced base type. This way, no one
- -- else in the compiler has to worry about the base attribute.
-
- else
- Set_Entity (N, Base_Type (Entity (P)));
- Rewrite (N,
- New_Reference_To (Entity (N), Loc));
- Analyze (N);
- end if;
+ Set_Entity (N, Base_Type (Entity (P)));
+ Rewrite (N, New_Reference_To (Entity (N), Loc));
+ Analyze (N);
end Base;
---------
Check_E0;
if not Is_Object_Reference (P) then
- Error_Attr ("prefix for % attribute must be object", P);
+ Error_Attr_P ("prefix for % attribute must be object");
-- What about the access object cases ???
Check_Type;
if not Is_Record_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be record type", P);
+ Error_Attr_P ("prefix of % attribute must be record type");
end if;
if Bytes_Big_Endian xor Reverse_Bit_Order (P_Type) then
-- immediately and sets an appropriate type.
when Attribute_Bit_Position =>
-
if Comes_From_Source (N) then
Check_Component;
end if;
begin
Check_E0;
- if Nkind (P) = N_Identifier
- or else Nkind (P) = N_Expanded_Name
- then
+ if Nkind_In (P, N_Identifier, N_Expanded_Name) then
Ent := Entity (P);
if not Is_Entry (Ent) then
-- Class --
-----------
- when Attribute_Class => Class : declare
- begin
+ when Attribute_Class =>
Check_Restriction (No_Dispatch, N);
- Check_Either_E0_Or_E1;
-
- -- If we have an expression present, then really this is a conversion
- -- and the tree must be reformed into a proper conversion. This is a
- -- Replace rather than a Rewrite, because the original tree is junk.
- -- If expression is overloaded, propagate interpretations to new one.
-
- if Present (E1) then
- Replace (N,
- Make_Type_Conversion (Loc,
- Subtype_Mark =>
- Make_Attribute_Reference (Loc,
- Prefix => Prefix (N),
- Attribute_Name => Name_Class),
- Expression => Relocate_Node (E1)));
-
- Save_Interps (E1, Expression (N));
- Analyze (N);
-
- -- Otherwise we just need to find the proper type
-
- else
- Find_Type (N);
- end if;
-
- end Class;
+ Check_E0;
+ Find_Type (N);
------------------
-- Code_Address --
then
Error_Attr ("invalid prefix for % attribute", P);
Set_Address_Taken (Entity (P));
+
+ -- Issue an error if the prefix denotes an eliminated subprogram
+
+ else
+ Check_For_Eliminated_Subprogram (P, Entity (P));
end if;
Set_Etype (N, RTE (RE_Address));
+ ----------------------
+ -- Compiler_Version --
+ ----------------------
+
+ when Attribute_Compiler_Version =>
+ Check_E0;
+ Check_Standard_Prefix;
+ Rewrite (N, Make_String_Literal (Loc, "GNAT " & Gnat_Version_String));
+ Analyze_And_Resolve (N, Standard_String);
+
--------------------
-- Component_Size --
--------------------
if Warn_On_Obsolescent_Feature then
Error_Msg_N
("constrained for private type is an " &
- "obsolescent feature ('R'M 'J.4)?", N);
+ "obsolescent feature (RM J.4)?", N);
end if;
-- If we are within an instance, the attribute must be legal
end if;
-- Must have discriminants or be an access type designating
- -- a type with discriminants. If it is a classwide type is
+ -- a type with discriminants. If it is a classwide type is ???
-- has unknown discriminants.
if Has_Discriminants (P_Type)
-- Fall through if bad prefix
- Error_Attr
- ("prefix of % attribute must be object of discriminated type", P);
+ Error_Attr_P
+ ("prefix of % attribute must be object of discriminated type");
---------------
-- Copy_Sign --
begin
Check_E0;
- if Nkind (P) = N_Identifier
- or else Nkind (P) = N_Expanded_Name
- then
+ if Nkind_In (P, N_Identifier, N_Expanded_Name) then
Ent := Entity (P);
if Ekind (Ent) /= E_Entry then
when Attribute_Default_Bit_Order => Default_Bit_Order :
begin
Check_Standard_Prefix;
- Check_E0;
if Bytes_Big_Endian then
Rewrite (N,
if not Is_Floating_Point_Type (P_Type)
and then not Is_Decimal_Fixed_Point_Type (P_Type)
then
- Error_Attr
- ("prefix of % attribute must be float or decimal type", P);
+ Error_Attr_P
+ ("prefix of % attribute must be float or decimal type");
end if;
Set_Etype (N, Universal_Integer);
Check_Floating_Point_Type_0;
Set_Etype (N, Universal_Integer);
+ -------------
+ -- Enabled --
+ -------------
+
+ when Attribute_Enabled =>
+ Check_Either_E0_Or_E1;
+
+ if Present (E1) then
+ if not Is_Entity_Name (E1) or else No (Entity (E1)) then
+ Error_Msg_N ("entity name expected for Enabled attribute", E1);
+ E1 := Empty;
+ end if;
+ end if;
+
+ if Nkind (P) /= N_Identifier then
+ Error_Msg_N ("identifier expected (check name)", P);
+ elsif Get_Check_Id (Chars (P)) = No_Check_Id then
+ Error_Msg_N ("& is not a recognized check name", P);
+ end if;
+
+ Set_Etype (N, Standard_Boolean);
+
--------------
-- Enum_Rep --
--------------
and then
Ekind (Entity (P)) /= E_Enumeration_Literal)
then
- Error_Attr
+ Error_Attr_P
("prefix of %attribute must be " &
- "discrete type/object or enum literal", P);
+ "discrete type/object or enum literal");
end if;
end if;
Set_Etype (N, Universal_Integer);
end Enum_Rep;
+ --------------
+ -- Enum_Val --
+ --------------
+
+ when Attribute_Enum_Val => Enum_Val : begin
+ Check_E1;
+ Check_Type;
+
+ if not Is_Enumeration_Type (P_Type) then
+ Error_Attr_P ("prefix of % attribute must be enumeration type");
+ end if;
+
+ -- If the enumeration type has a standard representation, the effect
+ -- is the same as 'Val, so rewrite the attribute as a 'Val.
+
+ if not Has_Non_Standard_Rep (P_Base_Type) then
+ Rewrite (N,
+ Make_Attribute_Reference (Loc,
+ Prefix => Relocate_Node (Prefix (N)),
+ Attribute_Name => Name_Val,
+ Expressions => New_List (Relocate_Node (E1))));
+ Analyze_And_Resolve (N, P_Base_Type);
+
+ -- Non-standard representation case (enumeration with holes)
+
+ else
+ Check_Enum_Image;
+ Resolve (E1, Any_Integer);
+ Set_Etype (N, P_Base_Type);
+ end if;
+ end Enum_Val;
+
-------------
-- Epsilon --
-------------
Set_Etype (N, Standard_String);
if not Is_Tagged_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be tagged", P);
+ Error_Attr_P ("prefix of % attribute must be tagged");
+ end if;
+
+ ---------------
+ -- Fast_Math --
+ ---------------
+
+ when Attribute_Fast_Math =>
+ Check_Standard_Prefix;
+
+ if Opt.Fast_Math then
+ Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
+ else
+ Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
end if;
-----------
Set_Etype (N, P_Base_Type);
Resolve (E1, P_Base_Type);
+ --------------
+ -- From_Any --
+ --------------
+
+ when Attribute_From_Any =>
+ Check_E1;
+ Check_PolyORB_Attribute;
+ Set_Etype (N, P_Base_Type);
+
-----------------------
-- Has_Access_Values --
-----------------------
Set_Etype (N, Standard_Boolean);
-----------------------
+ -- Has_Tagged_Values --
+ -----------------------
+
+ when Attribute_Has_Tagged_Values =>
+ Check_Type;
+ Check_E0;
+ Set_Etype (N, Standard_Boolean);
+
+ -----------------------
-- Has_Discriminants --
-----------------------
if Etype (P) = Standard_Exception_Type then
Set_Etype (N, RTE (RE_Exception_Id));
+ -- Ada 2005 (AI-345): Attribute 'Identity may be applied to
+ -- task interface class-wide types.
+
elsif Is_Task_Type (Etype (P))
or else (Is_Access_Type (Etype (P))
- and then Is_Task_Type (Designated_Type (Etype (P))))
+ and then Is_Task_Type (Designated_Type (Etype (P))))
+ or else (Ada_Version >= Ada_05
+ and then Ekind (Etype (P)) = E_Class_Wide_Type
+ and then Is_Interface (Etype (P))
+ and then Is_Task_Interface (Etype (P)))
then
Resolve (P);
Set_Etype (N, RTE (RO_AT_Task_Id));
else
- Error_Attr ("prefix of % attribute must be a task or an "
- & "exception", P);
+ if Ada_Version >= Ada_05 then
+ Error_Attr_P
+ ("prefix of % attribute must be an exception, a " &
+ "task or a task interface class-wide object");
+ else
+ Error_Attr_P
+ ("prefix of % attribute must be a task or an exception");
+ end if;
end if;
-----------
when Attribute_Img => Img :
begin
+ Check_E0;
Set_Etype (N, Standard_String);
if not Is_Scalar_Type (P_Type)
or else (Is_Entity_Name (P) and then Is_Type (Entity (P)))
then
- Error_Attr
- ("prefix of % attribute must be scalar object name", N);
+ Error_Attr_P
+ ("prefix of % attribute must be scalar object name");
end if;
Check_Enum_Image;
Check_E1;
Check_Integer_Type;
Resolve (E1, Any_Fixed);
+
+ -- Signal an error if argument type is not a specific fixed-point
+ -- subtype. An error has been signalled already if the argument
+ -- was not of a fixed-point type.
+
+ if Etype (E1) = Any_Fixed and then not Error_Posted (E1) then
+ Error_Attr ("argument of % must be of a fixed-point type", E1);
+ end if;
+
+ Set_Etype (N, P_Base_Type);
+
+ -------------------
+ -- Invalid_Value --
+ -------------------
+
+ when Attribute_Invalid_Value =>
+ Check_E0;
+ Check_Scalar_Type;
Set_Etype (N, P_Base_Type);
+ Invalid_Value_Used := True;
-----------
-- Large --
Check_E0;
Set_Etype (N, Universal_Integer);
+ ----------------------
+ -- Machine_Rounding --
+ ----------------------
+
+ when Attribute_Machine_Rounding =>
+ Check_Floating_Point_Type_1;
+ Set_Etype (N, P_Base_Type);
+ Resolve (E1, P_Base_Type);
+
--------------------
-- Machine_Rounds --
--------------------
if not Is_Entity_Name (P)
or else not Is_Subprogram (Entity (P))
then
- Error_Attr ("prefix of % attribute must be subprogram", P);
+ Error_Attr_P ("prefix of % attribute must be subprogram");
end if;
Check_Either_E0_Or_E1;
-- Case of attribute used as actual for subprogram (positional)
- elsif (Nkind (Parnt) = N_Procedure_Call_Statement
- or else
- Nkind (Parnt) = N_Function_Call)
+ elsif Nkind_In (Parnt, N_Procedure_Call_Statement,
+ N_Function_Call)
and then Is_Entity_Name (Name (Parnt))
then
Must_Be_Imported (Entity (Name (Parnt)));
-- Case of attribute used as actual for subprogram (named)
elsif Nkind (Parnt) = N_Parameter_Association
- and then (Nkind (GParnt) = N_Procedure_Call_Statement
- or else
- Nkind (GParnt) = N_Function_Call)
+ and then Nkind_In (GParnt, N_Procedure_Call_Statement,
+ N_Function_Call)
and then Is_Entity_Name (Name (GParnt))
then
Must_Be_Imported (Entity (Name (GParnt)));
Bad_Null_Parameter
("Null_Parameter must be actual or default parameter");
end if;
-
end Null_Parameter;
-----------------
Check_Not_Incomplete_Type;
Set_Etype (N, Universal_Integer);
+ ---------
+ -- Old --
+ ---------
+
+ when Attribute_Old =>
+ Check_E0;
+ Set_Etype (N, P_Type);
+
+ if No (Current_Subprogram) then
+ Error_Attr ("attribute % can only appear within subprogram", N);
+ end if;
+
+ if Is_Limited_Type (P_Type) then
+ Error_Attr ("attribute % cannot apply to limited objects", P);
+ end if;
+
+ if Is_Entity_Name (P)
+ and then Is_Constant_Object (Entity (P))
+ then
+ Error_Msg_N
+ ("?attribute Old applied to constant has no effect", P);
+ end if;
+
+ -- Check that the expression does not refer to local entities
+
+ Check_Local : declare
+ Subp : Entity_Id := Current_Subprogram;
+
+ function Process (N : Node_Id) return Traverse_Result;
+ -- Check that N does not contain references to local variables
+ -- or other local entities of Subp.
+
+ -------------
+ -- Process --
+ -------------
+
+ function Process (N : Node_Id) return Traverse_Result is
+ begin
+ if Is_Entity_Name (N)
+ and then not Is_Formal (Entity (N))
+ and then Enclosing_Subprogram (Entity (N)) = Subp
+ then
+ Error_Msg_Node_1 := Entity (N);
+ Error_Attr
+ ("attribute % cannot refer to local variable&", N);
+ end if;
+
+ return OK;
+ end Process;
+
+ procedure Check_No_Local is new Traverse_Proc;
+
+ -- Start of processing for Check_Local
+
+ begin
+ Check_No_Local (P);
+
+ if In_Parameter_Specification (P) then
+
+ -- We have additional restrictions on using 'Old in parameter
+ -- specifications.
+
+ if Present (Enclosing_Subprogram (Current_Subprogram)) then
+
+ -- Check that there is no reference to the enclosing
+ -- subprogram local variables. Otherwise, we might end
+ -- up being called from the enclosing subprogram and thus
+ -- using 'Old on a local variable which is not defined
+ -- at entry time.
+
+ Subp := Enclosing_Subprogram (Current_Subprogram);
+ Check_No_Local (P);
+
+ else
+ -- We must prevent default expression of library-level
+ -- subprogram from using 'Old, as the subprogram may be
+ -- used in elaboration code for which there is no enclosing
+ -- subprogram.
+
+ Error_Attr
+ ("attribute % can only appear within subprogram", N);
+ end if;
+ end if;
+ end Check_Local;
+
------------
-- Output --
------------
-- Partition_ID --
------------------
- when Attribute_Partition_ID =>
+ when Attribute_Partition_ID => Partition_Id :
+ begin
Check_E0;
if P_Type /= Any_Type then
if not Is_Library_Level_Entity (Entity (P)) then
- Error_Attr
- ("prefix of % attribute must be library-level entity", P);
+ Error_Attr_P
+ ("prefix of % attribute must be library-level entity");
- -- The defining entity of prefix should not be declared inside
- -- a Pure unit. RM E.1(8).
- -- The Is_Pure flag has been set during declaration.
+ -- The defining entity of prefix should not be declared inside a
+ -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
elsif Is_Entity_Name (P)
and then Is_Pure (Entity (P))
then
- Error_Attr
- ("prefix of % attribute must not be declared pure", P);
+ Error_Attr_P
+ ("prefix of % attribute must not be declared pure");
end if;
end if;
Set_Etype (N, Universal_Integer);
+ end Partition_Id;
-------------------------
-- Passed_By_Reference --
end if;
end if;
+ --------------
+ -- Priority --
+ --------------
+
+ -- Ada 2005 (AI-327): Dynamic ceiling priorities
+
+ when Attribute_Priority =>
+ if Ada_Version < Ada_05 then
+ Error_Attr ("% attribute is allowed only in Ada 2005 mode", P);
+ end if;
+
+ Check_E0;
+
+ -- The prefix must be a protected object (AARM D.5.2 (2/2))
+
+ Analyze (P);
+
+ if Is_Protected_Type (Etype (P))
+ or else (Is_Access_Type (Etype (P))
+ and then Is_Protected_Type (Designated_Type (Etype (P))))
+ then
+ Resolve (P, Etype (P));
+ else
+ Error_Attr_P ("prefix of % attribute must be a protected object");
+ end if;
+
+ Set_Etype (N, Standard_Integer);
+
+ -- Must be called from within a protected procedure or entry of the
+ -- protected object.
+
+ declare
+ S : Entity_Id;
+
+ begin
+ S := Current_Scope;
+ while S /= Etype (P)
+ and then S /= Standard_Standard
+ loop
+ S := Scope (S);
+ end loop;
+
+ if S = Standard_Standard then
+ Error_Attr ("the attribute % is only allowed inside protected "
+ & "operations", P);
+ end if;
+ end;
+
+ Validate_Non_Static_Attribute_Function_Call;
+
-----------
-- Range --
-----------
("(Ada 83) % attribute not allowed for scalar type", P);
end if;
+ ------------
+ -- Result --
+ ------------
+
+ when Attribute_Result => Result : declare
+ CS : Entity_Id := Current_Scope;
+ PS : Entity_Id := Scope (CS);
+
+ begin
+ -- If the enclosing subprogram is always inlined, the enclosing
+ -- postcondition will not be propagated to the expanded call.
+
+ if Has_Pragma_Inline_Always (PS)
+ and then Warn_On_Redundant_Constructs
+ then
+ Error_Msg_N
+ ("postconditions on inlined functions not enforced?", N);
+ end if;
+
+ -- If we are in the scope of a function and in Spec_Expression mode,
+ -- this is likely the prescan of the postcondition pragma, and we
+ -- just set the proper type. If there is an error it will be caught
+ -- when the real Analyze call is done.
+
+ if Ekind (CS) = E_Function
+ and then In_Spec_Expression
+ then
+ -- Check OK prefix
+
+ if Chars (CS) /= Chars (P) then
+ Error_Msg_NE
+ ("incorrect prefix for % attribute, expected &", P, CS);
+ Error_Attr;
+ end if;
+
+ Set_Etype (N, Etype (CS));
+
+ -- If several functions with that name are visible,
+ -- the intended one is the current scope.
+
+ if Is_Overloaded (P) then
+ Set_Entity (P, CS);
+ Set_Is_Overloaded (P, False);
+ end if;
+
+ -- Body case, where we must be inside a generated _Postcondition
+ -- procedure, and the prefix must be on the scope stack, or else
+ -- the attribute use is definitely misplaced. The condition itself
+ -- may have generated transient scopes, and is not necessarily the
+ -- current one.
+
+ else
+ while Present (CS)
+ and then CS /= Standard_Standard
+ loop
+ if Chars (CS) = Name_uPostconditions then
+ exit;
+ else
+ CS := Scope (CS);
+ end if;
+ end loop;
+
+ PS := Scope (CS);
+
+ if Chars (CS) = Name_uPostconditions
+ and then Ekind (PS) = E_Function
+ then
+ -- Check OK prefix
+
+ if Nkind_In (P, N_Identifier, N_Operator_Symbol)
+ and then Chars (P) = Chars (PS)
+ then
+ null;
+
+ -- Within an instance, the prefix designates the local renaming
+ -- of the original generic.
+
+ elsif Is_Entity_Name (P)
+ and then Ekind (Entity (P)) = E_Function
+ and then Present (Alias (Entity (P)))
+ and then Chars (Alias (Entity (P))) = Chars (PS)
+ then
+ null;
+
+ else
+ Error_Msg_NE
+ ("incorrect prefix for % attribute, expected &", P, PS);
+ Error_Attr;
+ end if;
+
+ Rewrite (N,
+ Make_Identifier (Sloc (N),
+ Chars => Name_uResult));
+ Analyze_And_Resolve (N, Etype (PS));
+
+ else
+ Error_Attr
+ ("% attribute can only appear" &
+ " in function Postcondition pragma", P);
+ end if;
+ end if;
+ end Result;
+
------------------
-- Range_Length --
------------------
when Attribute_Range_Length =>
+ Check_E0;
Check_Discrete_Type;
Set_Etype (N, Universal_Integer);
Check_Stream_Attribute (TSS_Stream_Read);
Set_Etype (N, Standard_Void_Type);
Resolve (N, Standard_Void_Type);
- Note_Possible_Modification (E2);
+ Note_Possible_Modification (E2, Sure => True);
---------------
-- Remainder --
-- Size --
----------
- when Attribute_Size | Attribute_VADS_Size =>
+ when Attribute_Size | Attribute_VADS_Size => Size :
+ begin
Check_E0;
-- If prefix is parameterless function call, rewrite and resolve
Check_Object_Reference (P);
elsif Is_Entity_Name (P)
- and then Is_Type (Entity (P))
+ and then (Is_Type (Entity (P))
+ or else Ekind (Entity (P)) = E_Enumeration_Literal)
then
null;
null;
else
- Error_Attr ("invalid prefix for % attribute", P);
+ Error_Attr_P ("invalid prefix for % attribute");
end if;
Check_Not_Incomplete_Type;
+ Check_Not_CPP_Type;
Set_Etype (N, Universal_Integer);
+ end Size;
-----------
-- Small --
-- Storage_Pool --
------------------
- when Attribute_Storage_Pool =>
+ when Attribute_Storage_Pool => Storage_Pool :
+ begin
+ Check_E0;
+
if Is_Access_Type (P_Type) then
- Check_E0;
+ if Ekind (P_Type) = E_Access_Subprogram_Type then
+ Error_Attr_P
+ ("cannot use % attribute for access-to-subprogram type");
+ end if;
-- Set appropriate entity
Validate_Remote_Access_To_Class_Wide_Type (N);
else
- Error_Attr ("prefix of % attribute must be access type", P);
+ Error_Attr_P ("prefix of % attribute must be access type");
end if;
+ end Storage_Pool;
------------------
-- Storage_Size --
------------------
- when Attribute_Storage_Size =>
+ when Attribute_Storage_Size => Storage_Size :
+ begin
+ Check_E0;
if Is_Task_Type (P_Type) then
- Check_E0;
Set_Etype (N, Universal_Integer);
elsif Is_Access_Type (P_Type) then
+ if Ekind (P_Type) = E_Access_Subprogram_Type then
+ Error_Attr_P
+ ("cannot use % attribute for access-to-subprogram type");
+ end if;
+
if Is_Entity_Name (P)
and then Is_Type (Entity (P))
then
- Check_E0;
Check_Type;
Set_Etype (N, Universal_Integer);
-- of an access value designating a task.
else
- Check_E0;
Check_Task_Prefix;
Set_Etype (N, Universal_Integer);
end if;
else
- Error_Attr
- ("prefix of % attribute must be access or task type", P);
+ Error_Attr_P ("prefix of % attribute must be access or task type");
end if;
+ end Storage_Size;
------------------
-- Storage_Unit --
then
Set_Etype (N, Universal_Integer);
else
- Error_Attr ("invalid prefix for % attribute", P);
+ Error_Attr_P ("invalid prefix for % attribute");
+ end if;
+
+ ---------------
+ -- Stub_Type --
+ ---------------
+
+ when Attribute_Stub_Type =>
+ Check_Type;
+ Check_E0;
+
+ if Is_Remote_Access_To_Class_Wide_Type (P_Type) then
+ Rewrite (N,
+ New_Occurrence_Of (Corresponding_Stub_Type (P_Type), Loc));
+ else
+ Error_Attr_P
+ ("prefix of% attribute must be remote access to classwide");
end if;
----------
-- Tag --
---------
- when Attribute_Tag =>
+ when Attribute_Tag => Tag :
+ begin
Check_E0;
Check_Dereference;
if not Is_Tagged_Type (P_Type) then
- Error_Attr ("prefix of % attribute must be tagged", P);
+ Error_Attr_P ("prefix of % attribute must be tagged");
-- Next test does not apply to generated code
-- why not, and what does the illegal reference mean???
and then not Is_Class_Wide_Type (P_Type)
and then Comes_From_Source (N)
then
- Error_Attr
- ("% attribute can only be applied to objects of class-wide type",
- P);
+ Error_Attr_P
+ ("% attribute can only be applied to objects " &
+ "of class - wide type");
+ end if;
+
+ -- The prefix cannot be an incomplete type. However, references
+ -- to 'Tag can be generated when expanding interface conversions,
+ -- and this is legal.
+
+ if Comes_From_Source (N) then
+ Check_Not_Incomplete_Type;
end if;
+ -- Set appropriate type
+
Set_Etype (N, RTE (RE_Tag));
+ end Tag;
-----------------
-- Target_Name --
begin
Check_Standard_Prefix;
- Check_E0;
TL := TN'Last;
if Nkind (P) /= N_Identifier
or else Chars (P) /= Name_System
then
- Error_Attr ("prefix of %attribute must be System", P);
+ Error_Attr_P ("prefix of %attribute must be System");
end if;
Generate_Reference (RTE (RE_Address), P);
Analyze_And_Resolve (E1, Any_Integer);
Set_Etype (N, RTE (RE_Address));
+ ------------
+ -- To_Any --
+ ------------
+
+ when Attribute_To_Any =>
+ Check_E1;
+ Check_PolyORB_Attribute;
+ Set_Etype (N, RTE (RE_Any));
+
----------------
-- Truncation --
----------------
Check_Not_Incomplete_Type;
Set_Etype (N, RTE (RE_Type_Class));
+ --------------
+ -- TypeCode --
+ --------------
+
+ when Attribute_TypeCode =>
+ Check_E0;
+ Check_PolyORB_Attribute;
+ Set_Etype (N, RTE (RE_TypeCode));
+
-----------------
-- UET_Address --
-----------------
if not Is_Entity_Name (P)
or else Ekind (Entity (P)) not in Named_Kind
then
- Error_Attr ("prefix for % attribute must be named number", P);
+ Error_Attr_P ("prefix for % attribute must be named number");
else
declare
Negative := False;
end if;
- if Nkind (Expr) /= N_Integer_Literal
- and then Nkind (Expr) /= N_Real_Literal
- then
+ if not Nkind_In (Expr, N_Integer_Literal, N_Real_Literal) then
Error_Attr
("named number for % attribute must be simple literal", N);
end if;
end if;
if not Is_Scalar_Type (P_Type) then
- Error_Attr ("object for % attribute must be of scalar type", P);
+ Error_Attr_P ("object for % attribute must be of scalar type");
end if;
Set_Etype (N, Standard_Boolean);
Check_E1;
Check_Scalar_Type;
+ -- Case of enumeration type
+
if Is_Enumeration_Type (P_Type) then
Check_Restriction (No_Enumeration_Maps, N);
+
+ -- Mark all enumeration literals as referenced, since the use of
+ -- the Value attribute can implicitly reference any of the
+ -- literals of the enumeration base type.
+
+ declare
+ Ent : Entity_Id := First_Literal (P_Base_Type);
+ begin
+ while Present (Ent) loop
+ Set_Referenced (Ent);
+ Next_Literal (Ent);
+ end loop;
+ end;
end if;
-- Set Etype before resolving expression because expansion of
-- used for First and Last of scalar types. Static is reset to False
-- if the type or index type is not statically constrained.
+ function Statically_Denotes_Entity (N : Node_Id) return Boolean;
+ -- Verify that the prefix of a potentially static array attribute
+ -- satisfies the conditions of 4.9 (14).
+
---------------
-- Aft_Value --
---------------
begin
Result := 1;
Delta_Val := Delta_Value (P_Type);
-
while Delta_Val < Ureal_Tenth loop
Delta_Val := Delta_Val * Ureal_10;
Result := Result + 1;
-----------------------
procedure Check_Expressions is
- E : Node_Id := E1;
-
+ E : Node_Id;
begin
+ E := E1;
while Present (E) loop
Check_Non_Static_Context (E);
Next (E);
-- Check that result is in bounds of the type if it is static
- if Is_In_Range (N, T) then
+ if Is_In_Range (N, T, Assume_Valid => False) then
null;
elsif Is_Out_Of_Range (N, T) then
end if;
end Set_Bounds;
+ -------------------------------
+ -- Statically_Denotes_Entity --
+ -------------------------------
+
+ function Statically_Denotes_Entity (N : Node_Id) return Boolean is
+ E : Entity_Id;
+
+ begin
+ if not Is_Entity_Name (N) then
+ return False;
+ else
+ E := Entity (N);
+ end if;
+
+ return
+ Nkind (Parent (E)) /= N_Object_Renaming_Declaration
+ or else Statically_Denotes_Entity (Renamed_Object (E));
+ end Statically_Denotes_Entity;
+
-- Start of processing for Eval_Attribute
begin
E2 := Empty;
end if;
+ -- Special processing for Enabled attribute. This attribute has a very
+ -- special prefix, and the easiest way to avoid lots of special checks
+ -- to protect this special prefix from causing trouble is to deal with
+ -- this attribute immediately and be done with it.
+
+ if Id = Attribute_Enabled then
+
+ -- Evaluate the Enabled attribute
+
+ -- We skip evaluation if the expander is not active. This is not just
+ -- an optimization. It is of key importance that we not rewrite the
+ -- attribute in a generic template, since we want to pick up the
+ -- setting of the check in the instance, and testing expander active
+ -- is as easy way of doing this as any.
+
+ if Expander_Active then
+ declare
+ C : constant Check_Id := Get_Check_Id (Chars (P));
+ R : Boolean;
+
+ begin
+ if No (E1) then
+ if C in Predefined_Check_Id then
+ R := Scope_Suppress (C);
+ else
+ R := Is_Check_Suppressed (Empty, C);
+ end if;
+
+ else
+ R := Is_Check_Suppressed (Entity (E1), C);
+ end if;
+
+ if R then
+ Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
+ else
+ Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
+ end if;
+ end;
+ end if;
+
+ return;
+ end if;
+
-- Special processing for cases where the prefix is an object. For
-- this purpose, a string literal counts as an object (attributes
-- of string literals can only appear in generated code).
if Present (AS) and then Is_Constrained (AS) then
P_Entity := AS;
- -- If we have an unconstrained type, cannot fold
+ -- If we have an unconstrained type we cannot fold
else
Check_Expressions;
then
P_Type := Etype (P_Entity);
- -- If the entity is an array constant with an unconstrained
- -- nominal subtype then get the type from the initial value.
- -- If the value has been expanded into assignments, the expression
- -- is not present and the attribute reference remains dynamic.
+ -- If the entity is an array constant with an unconstrained nominal
+ -- subtype then get the type from the initial value. If the value has
+ -- been expanded into assignments, there is no expression and the
+ -- attribute reference remains dynamic.
+
-- We could do better here and retrieve the type ???
if Ekind (P_Entity) = E_Constant
-- Definite must be folded if the prefix is not a generic type,
-- that is to say if we are within an instantiation. Same processing
-- applies to the GNAT attributes Has_Discriminants, Type_Class,
- -- and Unconstrained_Array.
+ -- Has_Tagged_Value, and Unconstrained_Array.
elsif (Id = Attribute_Definite
or else
or else
Id = Attribute_Has_Discriminants
or else
+ Id = Attribute_Has_Tagged_Values
+ or else
Id = Attribute_Type_Class
or else
Id = Attribute_Unconstrained_Array)
then
P_Type := P_Entity;
- -- We can fold 'Size applied to a type if the size is known
- -- (as happens for a size from an attribute definition clause).
- -- At this stage, this can happen only for types (e.g. record
- -- types) for which the size is always non-static. We exclude
- -- generic types from consideration (since they have bogus
- -- sizes set within templates).
+ -- We can fold 'Size applied to a type if the size is known (as happens
+ -- for a size from an attribute definition clause). At this stage, this
+ -- can happen only for types (e.g. record types) for which the size is
+ -- always non-static. We exclude generic types from consideration (since
+ -- they have bogus sizes set within templates).
elsif Id = Attribute_Size
and then Is_Type (P_Entity)
-- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
-- since we can't do anything with unconstrained arrays. In addition,
-- only the First, Last and Length attributes are possibly static.
- -- In addition Component_Size is possibly foldable, even though it
- -- can never be static.
- -- Definite, Has_Access_Values, Has_Discriminants, Type_Class, and
- -- Unconstrained_Array are again exceptions, because they apply as
- -- well to unconstrained types.
+ -- Definite, Has_Access_Values, Has_Discriminants, Has_Tagged_Values,
+ -- Type_Class, and Unconstrained_Array are again exceptions, because
+ -- they apply as well to unconstrained types.
+
+ -- In addition Component_Size is an exception since it is possibly
+ -- foldable, even though it is never static, and it does apply to
+ -- unconstrained arrays. Furthermore, it is essential to fold this
+ -- in the packed case, since otherwise the value will be incorrect.
elsif Id = Attribute_Definite
or else
or else
Id = Attribute_Has_Discriminants
or else
+ Id = Attribute_Has_Tagged_Values
+ or else
Id = Attribute_Type_Class
or else
Id = Attribute_Unconstrained_Array
+ or else
+ Id = Attribute_Component_Size
then
Static := False;
else
if not Is_Constrained (P_Type)
- or else (Id /= Attribute_Component_Size and then
- Id /= Attribute_First and then
- Id /= Attribute_Last and then
+ or else (Id /= Attribute_First and then
+ Id /= Attribute_Last and then
Id /= Attribute_Length)
then
Check_Expressions;
-- Again we compute the variable Static for easy reference later
-- (note that no array attributes are static in Ada 83).
- Static := Ada_Version >= Ada_95;
+ -- We also need to set Static properly for subsequent legality checks
+ -- which might otherwise accept non-static constants in contexts
+ -- where they are not legal.
+
+ Static := Ada_Version >= Ada_95
+ and then Statically_Denotes_Entity (P);
declare
N : Node_Id;
begin
N := First_Index (P_Type);
+
+ -- The expression is static if the array type is constrained
+ -- by given bounds, and not by an initial expression. Constant
+ -- strings are static in any case.
+
+ if Root_Type (P_Type) /= Standard_String then
+ Static :=
+ Static and then not Is_Constr_Subt_For_U_Nominal (P_Type);
+ end if;
+
while Present (N) loop
Static := Static and then Is_Static_Subtype (Etype (N));
-----------------
-- Constrained is never folded for now, there may be cases that
- -- could be handled at compile time. to be looked at later.
+ -- could be handled at compile time. To be looked at later.
when Attribute_Constrained =>
null;
Fold_Uint (N, Expr_Value (E1), Static);
end if;
+ --------------
+ -- Enum_Val --
+ --------------
+
+ when Attribute_Enum_Val => Enum_Val : declare
+ Lit : Node_Id;
+
+ begin
+ -- We have something like Enum_Type'Enum_Val (23), so search for a
+ -- corresponding value in the list of Enum_Rep values for the type.
+
+ Lit := First_Literal (P_Base_Type);
+ loop
+ if Enumeration_Rep (Lit) = Expr_Value (E1) then
+ Fold_Uint (N, Enumeration_Pos (Lit), Static);
+ exit;
+ end if;
+
+ Next_Literal (Lit);
+
+ if No (Lit) then
+ Apply_Compile_Time_Constraint_Error
+ (N, "no representation value matches",
+ CE_Range_Check_Failed,
+ Warn => not Static);
+ exit;
+ end if;
+ end loop;
+ end Enum_Val;
+
-------------
-- Epsilon --
-------------
Boolean_Literals (Has_Discriminants (P_Entity)), Loc));
Analyze_And_Resolve (N, Standard_Boolean);
+ -----------------------
+ -- Has_Tagged_Values --
+ -----------------------
+
+ when Attribute_Has_Tagged_Values =>
+ Rewrite (N, New_Occurrence_Of
+ (Boolean_Literals (Has_Tagged_Component (P_Root_Type)), Loc));
+ Analyze_And_Resolve (N, Standard_Boolean);
+
--------------
-- Identity --
--------------
-- Image is a scalar attribute, but is never static, because it is
-- not a static function (having a non-scalar argument (RM 4.9(22))
+ -- However, we can constant-fold the image of an enumeration literal
+ -- if names are available.
when Attribute_Image =>
- null;
+ if Is_Entity_Name (E1)
+ and then Ekind (Entity (E1)) = E_Enumeration_Literal
+ and then not Discard_Names (First_Subtype (Etype (E1)))
+ and then not Global_Discard_Names
+ then
+ declare
+ Lit : constant Entity_Id := Entity (E1);
+ Str : String_Id;
+ begin
+ Start_String;
+ Get_Unqualified_Decoded_Name_String (Chars (Lit));
+ Set_Casing (All_Upper_Case);
+ Store_String_Chars (Name_Buffer (1 .. Name_Len));
+ Str := End_String;
+ Rewrite (N, Make_String_Literal (Loc, Strval => Str));
+ Analyze_And_Resolve (N, Standard_String);
+ Set_Is_Static_Expression (N, False);
+ end;
+ end if;
---------
-- Img --
-- Integer_Value --
-------------------
+ -- We never try to fold Integer_Value (though perhaps we could???)
+
when Attribute_Integer_Value =>
null;
+ -------------------
+ -- Invalid_Value --
+ -------------------
+
+ -- Invalid_Value is a scalar attribute that is never static, because
+ -- the value is by design out of range.
+
+ when Attribute_Invalid_Value =>
+ null;
+
-----------
-- Large --
-----------
Ind : Node_Id;
begin
- -- In the case of a generic index type, the bounds may
- -- appear static but the computation is not meaningful,
- -- and may generate a spurious warning.
+ -- In the case of a generic index type, the bounds may appear static
+ -- but the computation is not meaningful in this case, and may
+ -- generate a spurious warning.
Ind := First_Index (P_Type);
-
while Present (Ind) loop
if Is_Generic_Type (Etype (Ind)) then
return;
Set_Bounds;
+ -- For two compile time values, we can compute length
+
if Compile_Time_Known_Value (Lo_Bound)
and then Compile_Time_Known_Value (Hi_Bound)
then
UI_Max (0, 1 + (Expr_Value (Hi_Bound) - Expr_Value (Lo_Bound))),
True);
end if;
+
+ -- One more case is where Hi_Bound and Lo_Bound are compile-time
+ -- comparable, and we can figure out the difference between them.
+
+ declare
+ Diff : aliased Uint;
+
+ begin
+ case
+ Compile_Time_Compare
+ (Lo_Bound, Hi_Bound, Diff'Access, Assume_Valid => False)
+ is
+ when EQ =>
+ Fold_Uint (N, Uint_1, False);
+
+ when GT =>
+ Fold_Uint (N, Uint_0, False);
+
+ when LT =>
+ if Diff /= No_Uint then
+ Fold_Uint (N, Diff + 1, False);
+ end if;
+
+ when others =>
+ null;
+ end case;
+ end;
end Length;
-------------
Fold_Uint (N, Uint_2, True);
end if;
+ ----------------------
+ -- Machine_Rounding --
+ ----------------------
+
+ -- Note: for the folding case, it is fine to treat Machine_Rounding
+ -- exactly the same way as Rounding, since this is one of the allowed
+ -- behaviors, and performance is not an issue here. It might be a bit
+ -- better to give the same result as it would give at run-time, even
+ -- though the non-determinism is certainly permitted.
+
+ when Attribute_Machine_Rounding =>
+ Fold_Ureal (N,
+ Eval_Fat.Rounding (P_Root_Type, Expr_Value_R (E1)), Static);
+
--------------------
-- Machine_Rounds --
--------------------
when Attribute_Range_Length =>
Set_Bounds;
+ -- Can fold if both bounds are compile time known
+
if Compile_Time_Known_Value (Hi_Bound)
and then Compile_Time_Known_Value (Lo_Bound)
then
Static);
end if;
+ -- One more case is where Hi_Bound and Lo_Bound are compile-time
+ -- comparable, and we can figure out the difference between them.
+
+ declare
+ Diff : aliased Uint;
+
+ begin
+ case
+ Compile_Time_Compare
+ (Lo_Bound, Hi_Bound, Diff'Access, Assume_Valid => False)
+ is
+ when EQ =>
+ Fold_Uint (N, Uint_1, False);
+
+ when GT =>
+ Fold_Uint (N, Uint_0, False);
+
+ when LT =>
+ if Diff /= No_Uint then
+ Fold_Uint (N, Diff + 1, False);
+ end if;
+
+ when others =>
+ null;
+ end case;
+ end;
+
---------------
-- Remainder --
---------------
when Attribute_Small =>
- -- The floating-point case is present only for Ada 83 compatability.
+ -- The floating-point case is present only for Ada 83 compatibility.
-- Note that strictly this is an illegal addition, since we are
-- extending an Ada 95 defined attribute, but we anticipate an
-- ARG ruling that will permit this.
-- We treat protected types like task types. It would make more
-- sense to have another enumeration value, but after all the
-- whole point of this feature is to be exactly DEC compatible,
- -- and changing the type Type_Clas would not meet this requirement.
+ -- and changing the type Type_Class would not meet this requirement.
elsif Is_Protected_Type (Typ) then
Id := RE_Type_Class_Task;
end if;
Rewrite (N, New_Occurrence_Of (RTE (Id), Loc));
-
end Type_Class;
-----------------------
when Attribute_Value_Size => Value_Size : declare
P_TypeA : constant Entity_Id := Underlying_Type (P_Type);
-
begin
if RM_Size (P_TypeA) /= Uint_0 then
Fold_Uint (N, RM_Size (P_TypeA), True);
end if;
-
end Value_Size;
-------------
-- nnn is set to 2 for Short_Float and Float (32 bit
-- floats), and 3 for Long_Float and Long_Long_Float.
- -- This is not quite right, but is good enough.
+ -- For machines where Long_Long_Float is the IEEE
+ -- extended precision type, the exponent takes 4 digits.
declare
Len : Int :=
begin
if Esize (P_Type) <= 32 then
Len := Len + 6;
- else
+ elsif Esize (P_Type) = 64 then
Len := Len + 7;
+ else
+ Len := Len + 8;
end if;
Fold_Uint (N, UI_From_Int (Len), True);
else
declare
R : constant Entity_Id := Root_Type (P_Type);
- Lo : constant Uint :=
- Expr_Value (Type_Low_Bound (P_Type));
- Hi : constant Uint :=
- Expr_Value (Type_High_Bound (P_Type));
+ Lo : constant Uint := Expr_Value (Type_Low_Bound (P_Type));
+ Hi : constant Uint := Expr_Value (Type_High_Bound (P_Type));
W : Nat;
Wt : Nat;
T : Uint;
-- Width for types derived from Standard.Character
-- and Standard.Wide_[Wide_]Character.
- elsif R = Standard_Character
- or else R = Standard_Wide_Character
- or else R = Standard_Wide_Wide_Character
- then
+ elsif Is_Standard_Character_Type (P_Type) then
W := 0;
-- Set W larger if needed
end if;
end Width;
+ -- The following attributes denote function that cannot be folded
+
+ when Attribute_From_Any |
+ Attribute_To_Any |
+ Attribute_TypeCode =>
+ null;
+
-- The following attributes can never be folded, and furthermore we
-- should not even have entered the case statement for any of these.
-- Note that in some cases, the values have already been folded as
Attribute_Caller |
Attribute_Class |
Attribute_Code_Address |
+ Attribute_Compiler_Version |
Attribute_Count |
Attribute_Default_Bit_Order |
Attribute_Elaborated |
Attribute_Elab_Body |
Attribute_Elab_Spec |
+ Attribute_Enabled |
Attribute_External_Tag |
+ Attribute_Fast_Math |
Attribute_First_Bit |
Attribute_Input |
Attribute_Last_Bit |
Attribute_Maximum_Alignment |
+ Attribute_Old |
Attribute_Output |
Attribute_Partition_ID |
Attribute_Pool_Address |
Attribute_Position |
+ Attribute_Priority |
Attribute_Read |
+ Attribute_Result |
Attribute_Storage_Pool |
Attribute_Storage_Size |
Attribute_Storage_Unit |
+ Attribute_Stub_Type |
Attribute_Tag |
Attribute_Target_Name |
Attribute_Terminated |
-- An exception is the GNAT attribute Constrained_Array which is
-- defined to be a static attribute in all cases.
- if Nkind (N) = N_Integer_Literal
- or else Nkind (N) = N_Real_Literal
- or else Nkind (N) = N_Character_Literal
- or else Nkind (N) = N_String_Literal
+ if Nkind_In (N, N_Integer_Literal,
+ N_Real_Literal,
+ N_Character_Literal,
+ N_String_Literal)
or else (Is_Entity_Name (N)
and then Ekind (Entity (N)) = E_Enumeration_Literal)
then
else
null;
end if;
-
end Eval_Attribute;
------------------------------
and then Associated_Node_For_Itype (Anon) = Parent (Typ);
end Is_Anonymous_Tagged_Base;
+ --------------------------------
+ -- Name_Implies_Lvalue_Prefix --
+ --------------------------------
+
+ function Name_Implies_Lvalue_Prefix (Nam : Name_Id) return Boolean is
+ pragma Assert (Is_Attribute_Name (Nam));
+ begin
+ return Attribute_Name_Implies_Lvalue_Prefix (Get_Attribute_Id (Nam));
+ end Name_Implies_Lvalue_Prefix;
+
-----------------------
-- Resolve_Attribute --
-----------------------
Aname : constant Name_Id := Attribute_Name (N);
Attr_Id : constant Attribute_Id := Get_Attribute_Id (Aname);
Btyp : constant Entity_Id := Base_Type (Typ);
+ Des_Btyp : Entity_Id;
Index : Interp_Index;
It : Interp;
Nom_Subt : Entity_Id;
-- know will fail, so generate an appropriate warning.
if In_Instance_Body then
- Error_Msg_N
+ Error_Msg_F
("?non-local pointer cannot point to local object", P);
- Error_Msg_N
- ("?Program_Error will be raised at run time", P);
+ Error_Msg_F
+ ("\?Program_Error will be raised at run time", P);
Rewrite (N,
Make_Raise_Program_Error (Loc,
Reason => PE_Accessibility_Check_Failed));
return;
else
- Error_Msg_N
+ Error_Msg_F
("non-local pointer cannot point to local object", P);
-- Check for case where we have a missing access definition
if Is_Record_Type (Current_Scope)
and then
- (Nkind (Parent (N)) = N_Discriminant_Association
- or else
- Nkind (Parent (N)) = N_Index_Or_Discriminant_Constraint)
+ Nkind_In (Parent (N), N_Discriminant_Association,
+ N_Index_Or_Discriminant_Constraint)
then
Indic := Parent (Parent (N));
while Present (Indic)
if Present (Indic) then
Error_Msg_NE
("\use an access definition for" &
- " the access discriminant of&", N,
- Entity (Subtype_Mark (Indic)));
+ " the access discriminant of&",
+ N, Entity (Subtype_Mark (Indic)));
end if;
end if;
end if;
| Attribute_Unchecked_Access
| Attribute_Unrestricted_Access =>
+ Access_Attribute :
+ begin
if Is_Variable (P) then
- Note_Possible_Modification (P);
+ Note_Possible_Modification (P, Sure => False);
+ end if;
+
+ -- The following comes from a query by Adam Beneschan, concerning
+ -- improper use of universal_access in equality tests involving
+ -- anonymous access types. Another good reason for 'Ref, but
+ -- for now disable the test, which breaks several filed tests.
+
+ if Ekind (Typ) = E_Anonymous_Access_Type
+ and then Nkind_In (Parent (N), N_Op_Eq, N_Op_Ne)
+ and then False
+ then
+ Error_Msg_N ("need unique type to resolve 'Access", N);
+ Error_Msg_N ("\qualify attribute with some access type", N);
end if;
if Is_Entity_Name (P) then
if Is_Overloaded (P) then
Get_First_Interp (P, Index, It);
-
while Present (It.Nam) loop
-
if Type_Conformant (Designated_Type (Typ), It.Nam) then
Set_Entity (P, It.Nam);
- -- The prefix is definitely NOT overloaded anymore
- -- at this point, so we reset the Is_Overloaded
- -- flag to avoid any confusion when reanalyzing
- -- the node.
+ -- The prefix is definitely NOT overloaded anymore at
+ -- this point, so we reset the Is_Overloaded flag to
+ -- avoid any confusion when reanalyzing the node.
Set_Is_Overloaded (P, False);
+ Set_Is_Overloaded (N, False);
Generate_Reference (Entity (P), P);
exit;
end if;
Get_Next_Interp (Index, It);
end loop;
- -- If it is a subprogram name or a type, there is nothing
- -- to resolve.
+ -- If Prefix is a subprogram name, it is frozen by this
+ -- reference:
- elsif not Is_Overloadable (Entity (P))
- and then not Is_Type (Entity (P))
- then
+ -- If it is a type, there is nothing to resolve.
+ -- If it is an object, complete its resolution.
+
+ elsif Is_Overloadable (Entity (P)) then
+
+ -- Avoid insertion of freeze actions in spec expression mode
+
+ if not In_Spec_Expression then
+ Insert_Actions (N, Freeze_Entity (Entity (P), Loc));
+ end if;
+
+ elsif Is_Type (Entity (P)) then
+ null;
+ else
Resolve (P);
end if;
if not Is_Entity_Name (P) then
null;
- elsif Is_Abstract (Entity (P))
- and then Is_Overloadable (Entity (P))
+ elsif Is_Overloadable (Entity (P))
+ and then Is_Abstract_Subprogram (Entity (P))
then
- Error_Msg_N ("prefix of % attribute cannot be abstract", P);
+ Error_Msg_F ("prefix of % attribute cannot be abstract", P);
Set_Etype (N, Any_Type);
elsif Convention (Entity (P)) = Convention_Intrinsic then
if Ekind (Entity (P)) = E_Enumeration_Literal then
- Error_Msg_N
+ Error_Msg_F
("prefix of % attribute cannot be enumeration literal",
- P);
+ P);
else
- Error_Msg_N
+ Error_Msg_F
("prefix of % attribute cannot be intrinsic", P);
end if;
Set_Etype (N, Any_Type);
-
- elsif Is_Thread_Body (Entity (P)) then
- Error_Msg_N
- ("prefix of % attribute cannot be a thread body", P);
end if;
-- Assignments, return statements, components of aggregates,
or else
Ekind (Btyp) = E_Anonymous_Access_Protected_Subprogram_Type
then
+ -- Deal with convention mismatch
+
if Convention (Btyp) /= Convention (Entity (P)) then
- Error_Msg_N
- ("subprogram has invalid convention for context", P);
+ Error_Msg_FE
+ ("subprogram & has wrong convention", P, Entity (P));
+
+ Error_Msg_FE
+ ("\does not match convention of access type &",
+ P, Btyp);
+
+ if not Has_Convention_Pragma (Btyp) then
+ Error_Msg_FE
+ ("\probable missing pragma Convention for &",
+ P, Btyp);
+ end if;
else
Check_Subtype_Conformant
if Attr_Id = Attribute_Unchecked_Access then
Error_Msg_Name_1 := Aname;
- Error_Msg_N
+ Error_Msg_F
("attribute% cannot be applied to a subprogram", P);
elsif Aname = Name_Unrestricted_Access then
null; -- Nothing to check
- -- Check the static accessibility rule of 3.10.2(32)
- -- In an instance body, if subprogram and type are both
- -- local, other rules prevent dangling references, and no
- -- warning is needed.
+ -- Check the static accessibility rule of 3.10.2(32).
+ -- This rule also applies within the private part of an
+ -- instantiation. This rule does not apply to anonymous
+ -- access-to-subprogram types in access parameters.
elsif Attr_Id = Attribute_Access
+ and then not In_Instance_Body
+ and then
+ (Ekind (Btyp) = E_Access_Subprogram_Type
+ or else Is_Local_Anonymous_Access (Btyp))
+
and then Subprogram_Access_Level (Entity (P)) >
Type_Access_Level (Btyp)
+ then
+ Error_Msg_F
+ ("subprogram must not be deeper than access type", P);
+
+ -- Check the restriction of 3.10.2(32) that disallows the
+ -- access attribute within a generic body when the ultimate
+ -- ancestor of the type of the attribute is declared outside
+ -- of the generic unit and the subprogram is declared within
+ -- that generic unit. This includes any such attribute that
+ -- occurs within the body of a generic unit that is a child
+ -- of the generic unit where the subprogram is declared.
+ -- The rule also prohibits applying the attribute when the
+ -- access type is a generic formal access type (since the
+ -- level of the actual type is not known). This restriction
+ -- does not apply when the attribute type is an anonymous
+ -- access-to-subprogram type. Note that this check was
+ -- revised by AI-229, because the originally Ada 95 rule
+ -- was too lax. The original rule only applied when the
+ -- subprogram was declared within the body of the generic,
+ -- which allowed the possibility of dangling references).
+ -- The rule was also too strict in some case, in that it
+ -- didn't permit the access to be declared in the generic
+ -- spec, whereas the revised rule does (as long as it's not
+ -- a formal type).
+
+ -- There are a couple of subtleties of the test for applying
+ -- the check that are worth noting. First, we only apply it
+ -- when the levels of the subprogram and access type are the
+ -- same (the case where the subprogram is statically deeper
+ -- was applied above, and the case where the type is deeper
+ -- is always safe). Second, we want the check to apply
+ -- within nested generic bodies and generic child unit
+ -- bodies, but not to apply to an attribute that appears in
+ -- the generic unit's specification. This is done by testing
+ -- that the attribute's innermost enclosing generic body is
+ -- not the same as the innermost generic body enclosing the
+ -- generic unit where the subprogram is declared (we don't
+ -- want the check to apply when the access attribute is in
+ -- the spec and there's some other generic body enclosing
+ -- generic). Finally, there's no point applying the check
+ -- when within an instance, because any violations will have
+ -- been caught by the compilation of the generic unit.
+
+ elsif Attr_Id = Attribute_Access
+ and then not In_Instance
+ and then Present (Enclosing_Generic_Unit (Entity (P)))
+ and then Present (Enclosing_Generic_Body (N))
+ and then Enclosing_Generic_Body (N) /=
+ Enclosing_Generic_Body
+ (Enclosing_Generic_Unit (Entity (P)))
+ and then Subprogram_Access_Level (Entity (P)) =
+ Type_Access_Level (Btyp)
and then Ekind (Btyp) /=
E_Anonymous_Access_Subprogram_Type
and then Ekind (Btyp) /=
E_Anonymous_Access_Protected_Subprogram_Type
then
- if not In_Instance_Body then
+ -- The attribute type's ultimate ancestor must be
+ -- declared within the same generic unit as the
+ -- subprogram is declared. The error message is
+ -- specialized to say "ancestor" for the case where
+ -- the access type is not its own ancestor, since
+ -- saying simply "access type" would be very confusing.
+
+ if Enclosing_Generic_Unit (Entity (P)) /=
+ Enclosing_Generic_Unit (Root_Type (Btyp))
+ then
Error_Msg_N
- ("subprogram must not be deeper than access type",
- P);
+ ("''Access attribute not allowed in generic body",
+ N);
+
+ if Root_Type (Btyp) = Btyp then
+ Error_Msg_NE
+ ("\because " &
+ "access type & is declared outside " &
+ "generic unit (RM 3.10.2(32))", N, Btyp);
+ else
+ Error_Msg_NE
+ ("\because ancestor of " &
+ "access type & is declared outside " &
+ "generic unit (RM 3.10.2(32))", N, Btyp);
+ end if;
- elsif Scope (Entity (P)) /= Scope (Btyp) then
- Error_Msg_N
- ("subprogram must not be deeper than access type?",
- P);
- Error_Msg_N
- ("Constraint_Error will be raised ?", P);
- Set_Raises_Constraint_Error (N);
+ Error_Msg_NE
+ ("\move ''Access to private part, or " &
+ "(Ada 2005) use anonymous access type instead of &",
+ N, Btyp);
+
+ -- If the ultimate ancestor of the attribute's type is
+ -- a formal type, then the attribute is illegal because
+ -- the actual type might be declared at a higher level.
+ -- The error message is specialized to say "ancestor"
+ -- for the case where the access type is not its own
+ -- ancestor, since saying simply "access type" would be
+ -- very confusing.
+
+ elsif Is_Generic_Type (Root_Type (Btyp)) then
+ if Root_Type (Btyp) = Btyp then
+ Error_Msg_N
+ ("access type must not be a generic formal type",
+ N);
+ else
+ Error_Msg_N
+ ("ancestor access type must not be a generic " &
+ "formal type", N);
+ end if;
end if;
-
- -- Check the restriction of 3.10.2(32) that disallows
- -- the type of the access attribute to be declared
- -- outside a generic body when the subprogram is declared
- -- within that generic body.
-
- -- Ada2005: If the expected type is for an access
- -- parameter, this clause does not apply.
-
- elsif Present (Enclosing_Generic_Body (Entity (P)))
- and then Enclosing_Generic_Body (Entity (P)) /=
- Enclosing_Generic_Body (Btyp)
- and then
- Ekind (Btyp) /= E_Anonymous_Access_Subprogram_Type
- then
- Error_Msg_N
- ("access type must not be outside generic body", P);
end if;
end if;
-- If this is a renaming, an inherited operation, or a
- -- subprogram instance, use the original entity.
+ -- subprogram instance, use the original entity. This may make
+ -- the node type-inconsistent, so this transformation can only
+ -- be done if the node will not be reanalyzed. In particular,
+ -- if it is within a default expression, the transformation
+ -- must be delayed until the default subprogram is created for
+ -- it, when the enclosing subprogram is frozen.
if Is_Entity_Name (P)
and then Is_Overloadable (Entity (P))
and then Present (Alias (Entity (P)))
+ and then Expander_Active
then
Rewrite (P,
New_Occurrence_Of (Alias (Entity (P)), Sloc (P)));
if Attr_Id = Attribute_Unchecked_Access then
Error_Msg_Name_1 := Aname;
- Error_Msg_N
+ Error_Msg_F
("attribute% cannot be applied to protected operation", P);
end if;
Resolve (P);
end if;
- -- X'Access is illegal if X denotes a constant and the access
- -- type is access-to-variable. Same for 'Unchecked_Access.
- -- The rule does not apply to 'Unrestricted_Access.
+ -- X'Access is illegal if X denotes a constant and the access type
+ -- is access-to-variable. Same for 'Unchecked_Access. The rule
+ -- does not apply to 'Unrestricted_Access. If the reference is a
+ -- default-initialized aggregate component for a self-referential
+ -- type the reference is legal.
if not (Ekind (Btyp) = E_Access_Subprogram_Type
or else Ekind (Btyp) = E_Anonymous_Access_Subprogram_Type
- or else (Is_Record_Type (Btyp) and then
- Present (Corresponding_Remote_Type (Btyp)))
+ or else (Is_Record_Type (Btyp)
+ and then
+ Present (Corresponding_Remote_Type (Btyp)))
or else Ekind (Btyp) = E_Access_Protected_Subprogram_Type
or else Ekind (Btyp)
= E_Anonymous_Access_Protected_Subprogram_Type
or else Is_Variable (P)
or else Attr_Id = Attribute_Unrestricted_Access)
then
- if Comes_From_Source (N) then
- Error_Msg_N ("access-to-variable designates constant", P);
+ if Is_Entity_Name (P)
+ and then Is_Type (Entity (P))
+ then
+ -- Legality of a self-reference through an access
+ -- attribute has been verified in Analyze_Access_Attribute.
+
+ null;
+
+ elsif Comes_From_Source (N) then
+ Error_Msg_F ("access-to-variable designates constant", P);
+ end if;
+ end if;
+
+ Des_Btyp := Designated_Type (Btyp);
+
+ if Ada_Version >= Ada_05
+ and then Is_Incomplete_Type (Des_Btyp)
+ then
+ -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
+ -- imported entity, and the non-limited view is visible, make
+ -- use of it. If it is an incomplete subtype, use the base type
+ -- in any case.
+
+ if From_With_Type (Des_Btyp)
+ and then Present (Non_Limited_View (Des_Btyp))
+ then
+ Des_Btyp := Non_Limited_View (Des_Btyp);
+
+ elsif Ekind (Des_Btyp) = E_Incomplete_Subtype then
+ Des_Btyp := Etype (Des_Btyp);
end if;
end if;
or else Ekind (Btyp) = E_Anonymous_Access_Type)
then
-- Ada 2005 (AI-230): Check the accessibility of anonymous
- -- access types in record and array components. For a
- -- component definition the level is the same of the
- -- enclosing composite type.
+ -- access types for stand-alone objects, record and array
+ -- components, and return objects. For a component definition
+ -- the level is the same of the enclosing composite type.
if Ada_Version >= Ada_05
and then Is_Local_Anonymous_Access (Btyp)
and then Object_Access_Level (P) > Type_Access_Level (Btyp)
+ and then Attr_Id = Attribute_Access
then
-- In an instance, this is a runtime check, but one we
-- know will fail, so generate an appropriate warning.
if In_Instance_Body then
- Error_Msg_N
+ Error_Msg_F
("?non-local pointer cannot point to local object", P);
- Error_Msg_N
- ("?Program_Error will be raised at run time", P);
+ Error_Msg_F
+ ("\?Program_Error will be raised at run time", P);
Rewrite (N,
Make_Raise_Program_Error (Loc,
Reason => PE_Accessibility_Check_Failed));
Set_Etype (N, Typ);
+
else
- Error_Msg_N
+ Error_Msg_F
("non-local pointer cannot point to local object", P);
end if;
end if;
if Is_Dependent_Component_Of_Mutable_Object (P) then
- Error_Msg_N
+ Error_Msg_F
("illegal attribute for discriminant-dependent component",
P);
end if;
- -- Check the static matching rule of 3.10.2(27). The
- -- nominal subtype of the prefix must statically
- -- match the designated type.
+ -- Check static matching rule of 3.10.2(27). Nominal subtype
+ -- of the prefix must statically match the designated type.
Nom_Subt := Etype (P);
if Is_Constr_Subt_For_U_Nominal (Nom_Subt) then
- Nom_Subt := Etype (Nom_Subt);
+ Nom_Subt := Base_Type (Nom_Subt);
end if;
if Is_Tagged_Type (Designated_Type (Typ)) then
-- If the attribute is in the context of an access
- -- parameter, then the prefix is allowed to be of
- -- the class-wide type (by AI-127).
+ -- parameter, then the prefix is allowed to be of the
+ -- class-wide type (by AI-127).
if Ekind (Typ) = E_Anonymous_Access_Type then
if not Covers (Designated_Type (Typ), Nom_Subt)
null;
else
- Error_Msg_NE
+ Error_Msg_FE
("type of prefix: & not compatible",
P, Nom_Subt);
- Error_Msg_NE
+ Error_Msg_FE
("\with &, the expected designated type",
P, Designated_Type (Typ));
end if;
(not Is_Class_Wide_Type (Designated_Type (Typ))
and then Is_Class_Wide_Type (Nom_Subt))
then
- Error_Msg_NE
+ Error_Msg_FE
("type of prefix: & is not covered", P, Nom_Subt);
- Error_Msg_NE
+ Error_Msg_FE
("\by &, the expected designated type" &
- " ('R'M 3.10.2 (27))", P, Designated_Type (Typ));
+ " (RM 3.10.2 (27))", P, Designated_Type (Typ));
end if;
if Is_Class_Wide_Type (Designated_Type (Typ))
(N, Etype (Designated_Type (Typ)));
end if;
- elsif not Subtypes_Statically_Match
- (Designated_Type (Base_Type (Typ)), Nom_Subt)
+ -- Ada 2005 (AI-363): Require static matching when designated
+ -- type has discriminants and a constrained partial view, since
+ -- in general objects of such types are mutable, so we can't
+ -- allow the access value to designate a constrained object
+ -- (because access values must be assumed to designate mutable
+ -- objects when designated type does not impose a constraint).
+
+ elsif Subtypes_Statically_Match (Des_Btyp, Nom_Subt) then
+ null;
+
+ elsif Has_Discriminants (Designated_Type (Typ))
+ and then not Is_Constrained (Des_Btyp)
and then
- not (Has_Discriminants (Designated_Type (Typ))
- and then
- not Is_Constrained
- (Designated_Type (Base_Type (Typ))))
+ (Ada_Version < Ada_05
+ or else
+ not Has_Constrained_Partial_View
+ (Designated_Type (Base_Type (Typ))))
then
- Error_Msg_N
+ null;
+
+ else
+ Error_Msg_F
("object subtype must statically match "
& "designated subtype", P);
if Is_Entity_Name (P)
and then Is_Array_Type (Designated_Type (Typ))
then
-
declare
D : constant Node_Id := Declaration_Node (Entity (P));
if Is_Entity_Name (P)
and then not Is_Protected_Type (Scope (Entity (P)))
then
- Error_Msg_N ("context requires a protected subprogram", P);
+ Error_Msg_F ("context requires a protected subprogram", P);
- -- Check accessibility of protected object against that
- -- of the access type, but only on user code, because
- -- the expander creates access references for handlers.
- -- If the context is an anonymous_access_to_protected,
- -- there are no accessibility checks either.
+ -- Check accessibility of protected object against that of the
+ -- access type, but only on user code, because the expander
+ -- creates access references for handlers. If the context is an
+ -- anonymous_access_to_protected, there are no accessibility
+ -- checks either. Omit check entirely for Unrestricted_Access.
elsif Object_Access_Level (P) > Type_Access_Level (Btyp)
and then Comes_From_Source (N)
and then Ekind (Btyp) = E_Access_Protected_Subprogram_Type
- and then No (Original_Access_Type (Typ))
+ and then Attr_Id /= Attribute_Unrestricted_Access
then
Accessibility_Message;
return;
Ekind (Btyp) = E_Anonymous_Access_Subprogram_Type)
and then Ekind (Etype (N)) = E_Access_Protected_Subprogram_Type
then
- Error_Msg_N ("context requires a non-protected subprogram", P);
+ Error_Msg_F ("context requires a non-protected subprogram", P);
end if;
-- The context cannot be a pool-specific type, but this is a
Wrong_Type (N, Typ);
end if;
- Set_Etype (N, Typ);
+ -- The context may be a constrained access type (however ill-
+ -- advised such subtypes might be) so in order to generate a
+ -- constraint check when needed set the type of the attribute
+ -- reference to the base type of the context.
+
+ Set_Etype (N, Btyp);
-- Check for incorrect atomic/volatile reference (RM C.6(12))
if Is_Atomic_Object (P)
and then not Is_Atomic (Designated_Type (Typ))
then
- Error_Msg_N
+ Error_Msg_F
("access to atomic object cannot yield access-to-" &
"non-atomic type", P);
elsif Is_Volatile_Object (P)
and then not Is_Volatile (Designated_Type (Typ))
then
- Error_Msg_N
+ Error_Msg_F
("access to volatile object cannot yield access-to-" &
"non-volatile type", P);
end if;
end if;
+ if Is_Entity_Name (P) then
+ Set_Address_Taken (Entity (P));
+ end if;
+ end Access_Attribute;
+
-------------
-- Address --
-------------
-- is not permitted here, since there is no context to resolve it.
when Attribute_Address | Attribute_Code_Address =>
+ Address_Attribute : begin
-- To be safe, assume that if the address of a variable is taken,
-- it may be modified via this address, so note modification.
if Is_Variable (P) then
- Note_Possible_Modification (P);
+ Note_Possible_Modification (P, Sure => False);
end if;
- if Nkind (P) in N_Subexpr
+ if Nkind (P) in N_Subexpr
and then Is_Overloaded (P)
then
Get_First_Interp (P, Index, It);
if Present (It.Nam) then
Error_Msg_Name_1 := Aname;
- Error_Msg_N
- ("prefix of % attribute cannot be overloaded", N);
- return;
+ Error_Msg_F
+ ("prefix of % attribute cannot be overloaded", P);
end if;
end if;
if not Is_Entity_Name (P)
- or else not Is_Overloadable (Entity (P))
+ or else not Is_Overloadable (Entity (P))
then
if not Is_Task_Type (Etype (P))
or else Nkind (P) = N_Explicit_Dereference
New_Occurrence_Of (Alias (Entity (P)), Sloc (P)));
end if;
+ if Is_Entity_Name (P) then
+ Set_Address_Taken (Entity (P));
+ end if;
+
+ if Nkind (P) = N_Slice then
+
+ -- Arr (X .. Y)'address is identical to Arr (X)'address,
+ -- even if the array is packed and the slice itself is not
+ -- addressable. Transform the prefix into an indexed component.
+
+ -- Note that the transformation is safe only if we know that
+ -- the slice is non-null. That is because a null slice can have
+ -- an out of bounds index value.
+
+ -- Right now, gigi blows up if given 'Address on a slice as a
+ -- result of some incorrect freeze nodes generated by the front
+ -- end, and this covers up that bug in one case, but the bug is
+ -- likely still there in the cases not handled by this code ???
+
+ -- It's not clear what 'Address *should* return for a null
+ -- slice with out of bounds indexes, this might be worth an ARG
+ -- discussion ???
+
+ -- One approach would be to do a length check unconditionally,
+ -- and then do the transformation below unconditionally, but
+ -- analyze with checks off, avoiding the problem of the out of
+ -- bounds index. This approach would interpret the address of
+ -- an out of bounds null slice as being the address where the
+ -- array element would be if there was one, which is probably
+ -- as reasonable an interpretation as any ???
+
+ declare
+ Loc : constant Source_Ptr := Sloc (P);
+ D : constant Node_Id := Discrete_Range (P);
+ Lo : Node_Id;
+
+ begin
+ if Is_Entity_Name (D)
+ and then
+ Not_Null_Range
+ (Type_Low_Bound (Entity (D)),
+ Type_High_Bound (Entity (D)))
+ then
+ Lo :=
+ Make_Attribute_Reference (Loc,
+ Prefix => (New_Occurrence_Of (Entity (D), Loc)),
+ Attribute_Name => Name_First);
+
+ elsif Nkind (D) = N_Range
+ and then Not_Null_Range (Low_Bound (D), High_Bound (D))
+ then
+ Lo := Low_Bound (D);
+
+ else
+ Lo := Empty;
+ end if;
+
+ if Present (Lo) then
+ Rewrite (P,
+ Make_Indexed_Component (Loc,
+ Prefix => Relocate_Node (Prefix (P)),
+ Expressions => New_List (Lo)));
+
+ Analyze_And_Resolve (P);
+ end if;
+ end;
+ end if;
+ end Address_Attribute;
+
---------------
-- AST_Entry --
---------------
when Attribute_Elaborated =>
null;
+ -------------
+ -- Enabled --
+ -------------
+
+ -- Prefix of Enabled attribute is a check name, which must be treated
+ -- specially and not touched by Resolve.
+
+ when Attribute_Enabled =>
+ null;
+
--------------------
-- Mechanism_Code --
--------------------
Process_Partition_Id (N);
return;
+ ------------------
+ -- Pool_Address --
+ ------------------
+
when Attribute_Pool_Address =>
Resolve (P);
LB : Node_Id;
HB : Node_Id;
- function Check_Discriminated_Prival
- (N : Node_Id)
- return Node_Id;
- -- The range of a private component constrained by a
- -- discriminant is rewritten to make the discriminant
- -- explicit. This solves some complex visibility problems
- -- related to the use of privals.
-
- --------------------------------
- -- Check_Discriminated_Prival --
- --------------------------------
-
- function Check_Discriminated_Prival
- (N : Node_Id)
- return Node_Id
- is
- begin
- if Is_Entity_Name (N)
- and then Ekind (Entity (N)) = E_In_Parameter
- and then not Within_Init_Proc
- then
- return Make_Identifier (Sloc (N), Chars (Entity (N)));
- else
- return Duplicate_Subexpr (N);
- end if;
- end Check_Discriminated_Prival;
-
- -- Start of processing for Range_Attribute
-
begin
if not Is_Entity_Name (P)
or else not Is_Type (Entity (P))
Resolve (P);
end if;
- -- Check whether prefix is (renaming of) private component
- -- of protected type.
-
- if Is_Entity_Name (P)
- and then Comes_From_Source (N)
- and then Is_Array_Type (Etype (P))
- and then Number_Dimensions (Etype (P)) = 1
- and then (Ekind (Scope (Entity (P))) = E_Protected_Type
- or else
- Ekind (Scope (Scope (Entity (P)))) =
- E_Protected_Type)
- then
- LB :=
- Check_Discriminated_Prival
- (Type_Low_Bound (Etype (First_Index (Etype (P)))));
-
- HB :=
- Check_Discriminated_Prival
- (Type_High_Bound (Etype (First_Index (Etype (P)))));
+ HB :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ Duplicate_Subexpr (P, Name_Req => True),
+ Attribute_Name => Name_Last,
+ Expressions => Expressions (N));
- else
- HB :=
- Make_Attribute_Reference (Loc,
- Prefix => Duplicate_Subexpr (P),
- Attribute_Name => Name_Last,
- Expressions => Expressions (N));
-
- LB :=
- Make_Attribute_Reference (Loc,
- Prefix => P,
- Attribute_Name => Name_First,
- Expressions => Expressions (N));
- end if;
+ LB :=
+ Make_Attribute_Reference (Loc,
+ Prefix => P,
+ Attribute_Name => Name_First,
+ Expressions => Expressions (N));
-- If the original was marked as Must_Not_Freeze (see code
-- in Sem_Ch3.Make_Index), then make sure the rewriting
return;
end Range_Attribute;
+ ------------
+ -- Result --
+ ------------
+
+ -- We will only come here during the prescan of a spec expression
+ -- containing a Result attribute. In that case the proper Etype has
+ -- already been set, and nothing more needs to be done here.
+
+ when Attribute_Result =>
+ null;
+
-----------------
-- UET_Address --
-----------------
when others => null;
end case;
+
+ -- If the prefix of the attribute is a class-wide type then it
+ -- will be expanded into a dispatching call to a predefined
+ -- primitive. Therefore we must check for potential violation
+ -- of such restriction.
+
+ if Is_Class_Wide_Type (Etype (P)) then
+ Check_Restriction (No_Dispatching_Calls, N);
+ end if;
end case;
-- Normally the Freezing is done by Resolve but sometimes the Prefix
is
Etyp : Entity_Id := Typ;
- function Has_Specified_Stream_Attribute
- (Typ : Entity_Id;
- Nam : TSS_Name_Type) return Boolean;
- -- True iff there is a visible attribute definition clause specifying
- -- attribute Nam for Typ.
-
- ------------------------------------
- -- Has_Specified_Stream_Attribute --
- ------------------------------------
-
- function Has_Specified_Stream_Attribute
- (Typ : Entity_Id;
- Nam : TSS_Name_Type) return Boolean
- is
- begin
- return False
- or else
- (Nam = TSS_Stream_Input
- and then Has_Specified_Stream_Input (Typ))
- or else
- (Nam = TSS_Stream_Output
- and then Has_Specified_Stream_Output (Typ))
- or else
- (Nam = TSS_Stream_Read
- and then Has_Specified_Stream_Read (Typ))
- or else
- (Nam = TSS_Stream_Write
- and then Has_Specified_Stream_Write (Typ));
- end Has_Specified_Stream_Attribute;
-
-- Start of processing for Stream_Attribute_Available
begin
-- We need some comments in this body ???
- if Has_Specified_Stream_Attribute (Typ, Nam) then
+ if Has_Stream_Attribute_Definition (Typ, Nam) then
return True;
end if;
end if;
if Nam = TSS_Stream_Input
- and then Is_Abstract (Typ)
+ and then Is_Abstract_Type (Typ)
and then not Is_Class_Wide_Type (Typ)
then
return False;
return True;
end if;
- if Nam = TSS_Stream_Input then
- return Ada_Version >= Ada_05
- and then Stream_Attribute_Available (Etyp, TSS_Stream_Read);
- elsif Nam = TSS_Stream_Output then
- return Ada_Version >= Ada_05
- and then Stream_Attribute_Available (Etyp, TSS_Stream_Write);
+ -- In Ada 2005, Input can invoke Read, and Output can invoke Write
+
+ if Nam = TSS_Stream_Input
+ and then Ada_Version >= Ada_05
+ and then Stream_Attribute_Available (Etyp, TSS_Stream_Read)
+ then
+ return True;
+
+ elsif Nam = TSS_Stream_Output
+ and then Ada_Version >= Ada_05
+ and then Stream_Attribute_Available (Etyp, TSS_Stream_Write)
+ then
+ return True;
end if;
-- Case of Read and Write: check for attribute definition clause that
while Etype (Etyp) /= Etyp loop
Etyp := Etype (Etyp);
- if Has_Specified_Stream_Attribute (Etyp, Nam) then
+ if Has_Stream_Attribute_Definition (Etyp, Nam) then
return True;
end if;
end loop;
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