diff options
Diffstat (limited to 'gcc-4.8/gcc/ada/freeze.adb')
| -rw-r--r-- | gcc-4.8/gcc/ada/freeze.adb | 6713 |
1 files changed, 0 insertions, 6713 deletions
diff --git a/gcc-4.8/gcc/ada/freeze.adb b/gcc-4.8/gcc/ada/freeze.adb deleted file mode 100644 index 234cdd2cb..000000000 --- a/gcc-4.8/gcc/ada/freeze.adb +++ /dev/null @@ -1,6713 +0,0 @@ ------------------------------------------------------------------------------- --- -- --- GNAT COMPILER COMPONENTS -- --- -- --- F R E E Z E -- --- -- --- B o d y -- --- -- --- Copyright (C) 1992-2012, Free Software Foundation, Inc. -- --- -- --- GNAT is free software; you can redistribute it and/or modify it under -- --- terms of the GNU General Public License as published by the Free Soft- -- --- ware Foundation; either version 3, or (at your option) any later ver- -- --- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- --- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- --- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- --- for more details. You should have received a copy of the GNU General -- --- Public License distributed with GNAT; see file COPYING3. If not, go to -- --- http://www.gnu.org/licenses for a complete copy of the license. -- --- -- --- GNAT was originally developed by the GNAT team at New York University. -- --- Extensive contributions were provided by Ada Core Technologies Inc. -- --- -- ------------------------------------------------------------------------------- - -with Atree; use Atree; -with Checks; use Checks; -with Debug; use Debug; -with Einfo; use Einfo; -with Elists; use Elists; -with Errout; use Errout; -with Exp_Ch3; use Exp_Ch3; -with Exp_Ch7; use Exp_Ch7; -with Exp_Disp; use Exp_Disp; -with Exp_Pakd; use Exp_Pakd; -with Exp_Util; use Exp_Util; -with Exp_Tss; use Exp_Tss; -with Layout; use Layout; -with Lib; use Lib; -with Namet; use Namet; -with Nlists; use Nlists; -with Nmake; use Nmake; -with Opt; use Opt; -with Restrict; use Restrict; -with Rident; use Rident; -with Rtsfind; use Rtsfind; -with Sem; use Sem; -with Sem_Aux; use Sem_Aux; -with Sem_Cat; use Sem_Cat; -with Sem_Ch6; use Sem_Ch6; -with Sem_Ch7; use Sem_Ch7; -with Sem_Ch8; use Sem_Ch8; -with Sem_Ch9; use Sem_Ch9; -with Sem_Ch13; use Sem_Ch13; -with Sem_Eval; use Sem_Eval; -with Sem_Mech; use Sem_Mech; -with Sem_Prag; use Sem_Prag; -with Sem_Res; use Sem_Res; -with Sem_Util; use Sem_Util; -with Sinfo; use Sinfo; -with Snames; use Snames; -with Stand; use Stand; -with Targparm; use Targparm; -with Tbuild; use Tbuild; -with Ttypes; use Ttypes; -with Uintp; use Uintp; -with Urealp; use Urealp; - -package body Freeze is - - ----------------------- - -- Local Subprograms -- - ----------------------- - - procedure Adjust_Esize_For_Alignment (Typ : Entity_Id); - -- Typ is a type that is being frozen. If no size clause is given, - -- but a default Esize has been computed, then this default Esize is - -- adjusted up if necessary to be consistent with a given alignment, - -- but never to a value greater than Long_Long_Integer'Size. This - -- is used for all discrete types and for fixed-point types. - - procedure Build_And_Analyze_Renamed_Body - (Decl : Node_Id; - New_S : Entity_Id; - After : in out Node_Id); - -- Build body for a renaming declaration, insert in tree and analyze - - procedure Check_Address_Clause (E : Entity_Id); - -- Apply legality checks to address clauses for object declarations, - -- at the point the object is frozen. Also ensure any initialization is - -- performed only after the object has been frozen. - - procedure Check_Component_Storage_Order - (Encl_Type : Entity_Id; - Comp : Entity_Id); - -- For an Encl_Type that has a Scalar_Storage_Order attribute definition - -- clause, verify that the component type is compatible. For arrays, - -- Comp is Empty; for records, it is the entity of the component under - -- consideration. - - procedure Check_Strict_Alignment (E : Entity_Id); - -- E is a base type. If E is tagged or has a component that is aliased - -- or tagged or contains something this is aliased or tagged, set - -- Strict_Alignment. - - procedure Check_Unsigned_Type (E : Entity_Id); - pragma Inline (Check_Unsigned_Type); - -- If E is a fixed-point or discrete type, then all the necessary work - -- to freeze it is completed except for possible setting of the flag - -- Is_Unsigned_Type, which is done by this procedure. The call has no - -- effect if the entity E is not a discrete or fixed-point type. - - procedure Freeze_And_Append - (Ent : Entity_Id; - N : Node_Id; - Result : in out List_Id); - -- Freezes Ent using Freeze_Entity, and appends the resulting list of - -- nodes to Result, modifying Result from No_List if necessary. N has - -- the same usage as in Freeze_Entity. - - procedure Freeze_Enumeration_Type (Typ : Entity_Id); - -- Freeze enumeration type. The Esize field is set as processing - -- proceeds (i.e. set by default when the type is declared and then - -- adjusted by rep clauses. What this procedure does is to make sure - -- that if a foreign convention is specified, and no specific size - -- is given, then the size must be at least Integer'Size. - - procedure Freeze_Static_Object (E : Entity_Id); - -- If an object is frozen which has Is_Statically_Allocated set, then - -- all referenced types must also be marked with this flag. This routine - -- is in charge of meeting this requirement for the object entity E. - - procedure Freeze_Subprogram (E : Entity_Id); - -- Perform freezing actions for a subprogram (create extra formals, - -- and set proper default mechanism values). Note that this routine - -- is not called for internal subprograms, for which neither of these - -- actions is needed (or desirable, we do not want for example to have - -- these extra formals present in initialization procedures, where they - -- would serve no purpose). In this call E is either a subprogram or - -- a subprogram type (i.e. an access to a subprogram). - - function Is_Fully_Defined (T : Entity_Id) return Boolean; - -- True if T is not private and has no private components, or has a full - -- view. Used to determine whether the designated type of an access type - -- should be frozen when the access type is frozen. This is done when an - -- allocator is frozen, or an expression that may involve attributes of - -- the designated type. Otherwise freezing the access type does not freeze - -- the designated type. - - procedure Process_Default_Expressions - (E : Entity_Id; - After : in out Node_Id); - -- This procedure is called for each subprogram to complete processing of - -- default expressions at the point where all types are known to be frozen. - -- The expressions must be analyzed in full, to make sure that all error - -- processing is done (they have only been pre-analyzed). If the expression - -- is not an entity or literal, its analysis may generate code which must - -- not be executed. In that case we build a function body to hold that - -- code. This wrapper function serves no other purpose (it used to be - -- called to evaluate the default, but now the default is inlined at each - -- point of call). - - procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id); - -- Typ is a record or array type that is being frozen. This routine sets - -- the default component alignment from the scope stack values if the - -- alignment is otherwise not specified. - - procedure Check_Debug_Info_Needed (T : Entity_Id); - -- As each entity is frozen, this routine is called to deal with the - -- setting of Debug_Info_Needed for the entity. This flag is set if - -- the entity comes from source, or if we are in Debug_Generated_Code - -- mode or if the -gnatdV debug flag is set. However, it never sets - -- the flag if Debug_Info_Off is set. This procedure also ensures that - -- subsidiary entities have the flag set as required. - - procedure Undelay_Type (T : Entity_Id); - -- T is a type of a component that we know to be an Itype. We don't want - -- this to have a Freeze_Node, so ensure it doesn't. Do the same for any - -- Full_View or Corresponding_Record_Type. - - procedure Warn_Overlay - (Expr : Node_Id; - Typ : Entity_Id; - Nam : Node_Id); - -- Expr is the expression for an address clause for entity Nam whose type - -- is Typ. If Typ has a default initialization, and there is no explicit - -- initialization in the source declaration, check whether the address - -- clause might cause overlaying of an entity, and emit a warning on the - -- side effect that the initialization will cause. - - ------------------------------- - -- Adjust_Esize_For_Alignment -- - ------------------------------- - - procedure Adjust_Esize_For_Alignment (Typ : Entity_Id) is - Align : Uint; - - begin - if Known_Esize (Typ) and then Known_Alignment (Typ) then - Align := Alignment_In_Bits (Typ); - - if Align > Esize (Typ) - and then Align <= Standard_Long_Long_Integer_Size - then - Set_Esize (Typ, Align); - end if; - end if; - end Adjust_Esize_For_Alignment; - - ------------------------------------ - -- Build_And_Analyze_Renamed_Body -- - ------------------------------------ - - procedure Build_And_Analyze_Renamed_Body - (Decl : Node_Id; - New_S : Entity_Id; - After : in out Node_Id) - is - Body_Decl : constant Node_Id := Unit_Declaration_Node (New_S); - Ent : constant Entity_Id := Defining_Entity (Decl); - Body_Node : Node_Id; - Renamed_Subp : Entity_Id; - - begin - -- If the renamed subprogram is intrinsic, there is no need for a - -- wrapper body: we set the alias that will be called and expanded which - -- completes the declaration. This transformation is only legal if the - -- renamed entity has already been elaborated. - - -- Note that it is legal for a renaming_as_body to rename an intrinsic - -- subprogram, as long as the renaming occurs before the new entity - -- is frozen. See RM 8.5.4 (5). - - if Nkind (Body_Decl) = N_Subprogram_Renaming_Declaration - and then Is_Entity_Name (Name (Body_Decl)) - then - Renamed_Subp := Entity (Name (Body_Decl)); - else - Renamed_Subp := Empty; - end if; - - if Present (Renamed_Subp) - and then Is_Intrinsic_Subprogram (Renamed_Subp) - and then - (not In_Same_Source_Unit (Renamed_Subp, Ent) - or else Sloc (Renamed_Subp) < Sloc (Ent)) - - -- We can make the renaming entity intrinsic if the renamed function - -- has an interface name, or if it is one of the shift/rotate - -- operations known to the compiler. - - and then (Present (Interface_Name (Renamed_Subp)) - or else Chars (Renamed_Subp) = Name_Rotate_Left - or else Chars (Renamed_Subp) = Name_Rotate_Right - or else Chars (Renamed_Subp) = Name_Shift_Left - or else Chars (Renamed_Subp) = Name_Shift_Right - or else Chars (Renamed_Subp) = Name_Shift_Right_Arithmetic) - then - Set_Interface_Name (Ent, Interface_Name (Renamed_Subp)); - - if Present (Alias (Renamed_Subp)) then - Set_Alias (Ent, Alias (Renamed_Subp)); - else - Set_Alias (Ent, Renamed_Subp); - end if; - - Set_Is_Intrinsic_Subprogram (Ent); - Set_Has_Completion (Ent); - - else - Body_Node := Build_Renamed_Body (Decl, New_S); - Insert_After (After, Body_Node); - Mark_Rewrite_Insertion (Body_Node); - Analyze (Body_Node); - After := Body_Node; - end if; - end Build_And_Analyze_Renamed_Body; - - ------------------------ - -- Build_Renamed_Body -- - ------------------------ - - function Build_Renamed_Body - (Decl : Node_Id; - New_S : Entity_Id) return Node_Id - is - Loc : constant Source_Ptr := Sloc (New_S); - -- We use for the source location of the renamed body, the location of - -- the spec entity. It might seem more natural to use the location of - -- the renaming declaration itself, but that would be wrong, since then - -- the body we create would look as though it was created far too late, - -- and this could cause problems with elaboration order analysis, - -- particularly in connection with instantiations. - - N : constant Node_Id := Unit_Declaration_Node (New_S); - Nam : constant Node_Id := Name (N); - Old_S : Entity_Id; - Spec : constant Node_Id := New_Copy_Tree (Specification (Decl)); - Actuals : List_Id := No_List; - Call_Node : Node_Id; - Call_Name : Node_Id; - Body_Node : Node_Id; - Formal : Entity_Id; - O_Formal : Entity_Id; - Param_Spec : Node_Id; - - Pref : Node_Id := Empty; - -- If the renamed entity is a primitive operation given in prefix form, - -- the prefix is the target object and it has to be added as the first - -- actual in the generated call. - - begin - -- Determine the entity being renamed, which is the target of the call - -- statement. If the name is an explicit dereference, this is a renaming - -- of a subprogram type rather than a subprogram. The name itself is - -- fully analyzed. - - if Nkind (Nam) = N_Selected_Component then - Old_S := Entity (Selector_Name (Nam)); - - elsif Nkind (Nam) = N_Explicit_Dereference then - Old_S := Etype (Nam); - - elsif Nkind (Nam) = N_Indexed_Component then - if Is_Entity_Name (Prefix (Nam)) then - Old_S := Entity (Prefix (Nam)); - else - Old_S := Entity (Selector_Name (Prefix (Nam))); - end if; - - elsif Nkind (Nam) = N_Character_Literal then - Old_S := Etype (New_S); - - else - Old_S := Entity (Nam); - end if; - - if Is_Entity_Name (Nam) then - - -- If the renamed entity is a predefined operator, retain full name - -- to ensure its visibility. - - if Ekind (Old_S) = E_Operator - and then Nkind (Nam) = N_Expanded_Name - then - Call_Name := New_Copy (Name (N)); - else - Call_Name := New_Reference_To (Old_S, Loc); - end if; - - else - if Nkind (Nam) = N_Selected_Component - and then Present (First_Formal (Old_S)) - and then - (Is_Controlling_Formal (First_Formal (Old_S)) - or else Is_Class_Wide_Type (Etype (First_Formal (Old_S)))) - then - - -- Retrieve the target object, to be added as a first actual - -- in the call. - - Call_Name := New_Occurrence_Of (Old_S, Loc); - Pref := Prefix (Nam); - - else - Call_Name := New_Copy (Name (N)); - end if; - - -- Original name may have been overloaded, but is fully resolved now - - Set_Is_Overloaded (Call_Name, False); - end if; - - -- For simple renamings, subsequent calls can be expanded directly as - -- calls to the renamed entity. The body must be generated in any case - -- for calls that may appear elsewhere. This is not done in the case - -- where the subprogram is an instantiation because the actual proper - -- body has not been built yet. - - if Ekind_In (Old_S, E_Function, E_Procedure) - and then Nkind (Decl) = N_Subprogram_Declaration - and then not Is_Generic_Instance (Old_S) - then - Set_Body_To_Inline (Decl, Old_S); - end if; - - -- The body generated for this renaming is an internal artifact, and - -- does not constitute a freeze point for the called entity. - - Set_Must_Not_Freeze (Call_Name); - - Formal := First_Formal (Defining_Entity (Decl)); - - if Present (Pref) then - declare - Pref_Type : constant Entity_Id := Etype (Pref); - Form_Type : constant Entity_Id := Etype (First_Formal (Old_S)); - - begin - -- The controlling formal may be an access parameter, or the - -- actual may be an access value, so adjust accordingly. - - if Is_Access_Type (Pref_Type) - and then not Is_Access_Type (Form_Type) - then - Actuals := New_List - (Make_Explicit_Dereference (Loc, Relocate_Node (Pref))); - - elsif Is_Access_Type (Form_Type) - and then not Is_Access_Type (Pref) - then - Actuals := New_List - (Make_Attribute_Reference (Loc, - Attribute_Name => Name_Access, - Prefix => Relocate_Node (Pref))); - else - Actuals := New_List (Pref); - end if; - end; - - elsif Present (Formal) then - Actuals := New_List; - - else - Actuals := No_List; - end if; - - if Present (Formal) then - while Present (Formal) loop - Append (New_Reference_To (Formal, Loc), Actuals); - Next_Formal (Formal); - end loop; - end if; - - -- If the renamed entity is an entry, inherit its profile. For other - -- renamings as bodies, both profiles must be subtype conformant, so it - -- is not necessary to replace the profile given in the declaration. - -- However, default values that are aggregates are rewritten when - -- partially analyzed, so we recover the original aggregate to insure - -- that subsequent conformity checking works. Similarly, if the default - -- expression was constant-folded, recover the original expression. - - Formal := First_Formal (Defining_Entity (Decl)); - - if Present (Formal) then - O_Formal := First_Formal (Old_S); - Param_Spec := First (Parameter_Specifications (Spec)); - while Present (Formal) loop - if Is_Entry (Old_S) then - if Nkind (Parameter_Type (Param_Spec)) /= - N_Access_Definition - then - Set_Etype (Formal, Etype (O_Formal)); - Set_Entity (Parameter_Type (Param_Spec), Etype (O_Formal)); - end if; - - elsif Nkind (Default_Value (O_Formal)) = N_Aggregate - or else Nkind (Original_Node (Default_Value (O_Formal))) /= - Nkind (Default_Value (O_Formal)) - then - Set_Expression (Param_Spec, - New_Copy_Tree (Original_Node (Default_Value (O_Formal)))); - end if; - - Next_Formal (Formal); - Next_Formal (O_Formal); - Next (Param_Spec); - end loop; - end if; - - -- If the renamed entity is a function, the generated body contains a - -- return statement. Otherwise, build a procedure call. If the entity is - -- an entry, subsequent analysis of the call will transform it into the - -- proper entry or protected operation call. If the renamed entity is - -- a character literal, return it directly. - - if Ekind (Old_S) = E_Function - or else Ekind (Old_S) = E_Operator - or else (Ekind (Old_S) = E_Subprogram_Type - and then Etype (Old_S) /= Standard_Void_Type) - then - Call_Node := - Make_Simple_Return_Statement (Loc, - Expression => - Make_Function_Call (Loc, - Name => Call_Name, - Parameter_Associations => Actuals)); - - elsif Ekind (Old_S) = E_Enumeration_Literal then - Call_Node := - Make_Simple_Return_Statement (Loc, - Expression => New_Occurrence_Of (Old_S, Loc)); - - elsif Nkind (Nam) = N_Character_Literal then - Call_Node := - Make_Simple_Return_Statement (Loc, - Expression => Call_Name); - - else - Call_Node := - Make_Procedure_Call_Statement (Loc, - Name => Call_Name, - Parameter_Associations => Actuals); - end if; - - -- Create entities for subprogram body and formals - - Set_Defining_Unit_Name (Spec, - Make_Defining_Identifier (Loc, Chars => Chars (New_S))); - - Param_Spec := First (Parameter_Specifications (Spec)); - while Present (Param_Spec) loop - Set_Defining_Identifier (Param_Spec, - Make_Defining_Identifier (Loc, - Chars => Chars (Defining_Identifier (Param_Spec)))); - Next (Param_Spec); - end loop; - - Body_Node := - Make_Subprogram_Body (Loc, - Specification => Spec, - Declarations => New_List, - Handled_Statement_Sequence => - Make_Handled_Sequence_Of_Statements (Loc, - Statements => New_List (Call_Node))); - - if Nkind (Decl) /= N_Subprogram_Declaration then - Rewrite (N, - Make_Subprogram_Declaration (Loc, - Specification => Specification (N))); - end if; - - -- Link the body to the entity whose declaration it completes. If - -- the body is analyzed when the renamed entity is frozen, it may - -- be necessary to restore the proper scope (see package Exp_Ch13). - - if Nkind (N) = N_Subprogram_Renaming_Declaration - and then Present (Corresponding_Spec (N)) - then - Set_Corresponding_Spec (Body_Node, Corresponding_Spec (N)); - else - Set_Corresponding_Spec (Body_Node, New_S); - end if; - - return Body_Node; - end Build_Renamed_Body; - - -------------------------- - -- Check_Address_Clause -- - -------------------------- - - procedure Check_Address_Clause (E : Entity_Id) is - Addr : constant Node_Id := Address_Clause (E); - Expr : Node_Id; - Decl : constant Node_Id := Declaration_Node (E); - Loc : constant Source_Ptr := Sloc (Decl); - Typ : constant Entity_Id := Etype (E); - - begin - if Present (Addr) then - Expr := Expression (Addr); - - if Needs_Constant_Address (Decl, Typ) then - Check_Constant_Address_Clause (Expr, E); - - -- Has_Delayed_Freeze was set on E when the address clause was - -- analyzed, and must remain set because we want the address - -- clause to be elaborated only after any entity it references - -- has been elaborated. - end if; - - -- If Rep_Clauses are to be ignored, remove address clause from - -- list attached to entity, because it may be illegal for gigi, - -- for example by breaking order of elaboration.. - - if Ignore_Rep_Clauses then - declare - Rep : Node_Id; - - begin - Rep := First_Rep_Item (E); - - if Rep = Addr then - Set_First_Rep_Item (E, Next_Rep_Item (Addr)); - - else - while Present (Rep) - and then Next_Rep_Item (Rep) /= Addr - loop - Rep := Next_Rep_Item (Rep); - end loop; - end if; - - if Present (Rep) then - Set_Next_Rep_Item (Rep, Next_Rep_Item (Addr)); - end if; - end; - - Rewrite (Addr, Make_Null_Statement (Sloc (E))); - - elsif not Error_Posted (Expr) - and then not Needs_Finalization (Typ) - then - Warn_Overlay (Expr, Typ, Name (Addr)); - end if; - - if Present (Expression (Decl)) then - - -- Capture initialization value at point of declaration - - Remove_Side_Effects (Expression (Decl)); - - -- Move initialization to freeze actions (once the object has - -- been frozen, and the address clause alignment check has been - -- performed. - - Append_Freeze_Action (E, - Make_Assignment_Statement (Loc, - Name => New_Occurrence_Of (E, Loc), - Expression => Expression (Decl))); - - Set_No_Initialization (Decl); - end if; - end if; - end Check_Address_Clause; - - ----------------------------- - -- Check_Compile_Time_Size -- - ----------------------------- - - procedure Check_Compile_Time_Size (T : Entity_Id) is - - procedure Set_Small_Size (T : Entity_Id; S : Uint); - -- Sets the compile time known size (32 bits or less) in the Esize - -- field, of T checking for a size clause that was given which attempts - -- to give a smaller size, and also checking for an alignment clause. - - function Size_Known (T : Entity_Id) return Boolean; - -- Recursive function that does all the work - - function Static_Discriminated_Components (T : Entity_Id) return Boolean; - -- If T is a constrained subtype, its size is not known if any of its - -- discriminant constraints is not static and it is not a null record. - -- The test is conservative and doesn't check that the components are - -- in fact constrained by non-static discriminant values. Could be made - -- more precise ??? - - -------------------- - -- Set_Small_Size -- - -------------------- - - procedure Set_Small_Size (T : Entity_Id; S : Uint) is - begin - if S > 32 then - return; - - -- Check for bad size clause given - - elsif Has_Size_Clause (T) then - if RM_Size (T) < S then - Error_Msg_Uint_1 := S; - Error_Msg_NE - ("size for& too small, minimum allowed is ^", - Size_Clause (T), T); - end if; - - -- Set size if not set already - - elsif Unknown_RM_Size (T) then - Set_RM_Size (T, S); - end if; - end Set_Small_Size; - - ---------------- - -- Size_Known -- - ---------------- - - function Size_Known (T : Entity_Id) return Boolean is - Index : Entity_Id; - Comp : Entity_Id; - Ctyp : Entity_Id; - Low : Node_Id; - High : Node_Id; - - begin - if Size_Known_At_Compile_Time (T) then - return True; - - -- Always True for scalar types. This is true even for generic formal - -- scalar types. We used to return False in the latter case, but the - -- size is known at compile time, even in the template, we just do - -- not know the exact size but that's not the point of this routine. - - elsif Is_Scalar_Type (T) - or else Is_Task_Type (T) - then - return True; - - -- Array types - - elsif Is_Array_Type (T) then - - -- String literals always have known size, and we can set it - - if Ekind (T) = E_String_Literal_Subtype then - Set_Small_Size (T, Component_Size (T) - * String_Literal_Length (T)); - return True; - - -- Unconstrained types never have known at compile time size - - elsif not Is_Constrained (T) then - return False; - - -- Don't do any recursion on type with error posted, since we may - -- have a malformed type that leads us into a loop. - - elsif Error_Posted (T) then - return False; - - -- Otherwise if component size unknown, then array size unknown - - elsif not Size_Known (Component_Type (T)) then - return False; - end if; - - -- Check for all indexes static, and also compute possible size - -- (in case it is less than 32 and may be packable). - - declare - Esiz : Uint := Component_Size (T); - Dim : Uint; - - begin - Index := First_Index (T); - while Present (Index) loop - if Nkind (Index) = N_Range then - Get_Index_Bounds (Index, Low, High); - - elsif Error_Posted (Scalar_Range (Etype (Index))) then - return False; - - else - Low := Type_Low_Bound (Etype (Index)); - High := Type_High_Bound (Etype (Index)); - end if; - - if not Compile_Time_Known_Value (Low) - or else not Compile_Time_Known_Value (High) - or else Etype (Index) = Any_Type - then - return False; - - else - Dim := Expr_Value (High) - Expr_Value (Low) + 1; - - if Dim >= 0 then - Esiz := Esiz * Dim; - else - Esiz := Uint_0; - end if; - end if; - - Next_Index (Index); - end loop; - - Set_Small_Size (T, Esiz); - return True; - end; - - -- Access types always have known at compile time sizes - - elsif Is_Access_Type (T) then - return True; - - -- For non-generic private types, go to underlying type if present - - elsif Is_Private_Type (T) - and then not Is_Generic_Type (T) - and then Present (Underlying_Type (T)) - then - -- Don't do any recursion on type with error posted, since we may - -- have a malformed type that leads us into a loop. - - if Error_Posted (T) then - return False; - else - return Size_Known (Underlying_Type (T)); - end if; - - -- Record types - - elsif Is_Record_Type (T) then - - -- A class-wide type is never considered to have a known size - - if Is_Class_Wide_Type (T) then - return False; - - -- A subtype of a variant record must not have non-static - -- discriminated components. - - elsif T /= Base_Type (T) - and then not Static_Discriminated_Components (T) - then - return False; - - -- Don't do any recursion on type with error posted, since we may - -- have a malformed type that leads us into a loop. - - elsif Error_Posted (T) then - return False; - end if; - - -- Now look at the components of the record - - declare - -- The following two variables are used to keep track of the - -- size of packed records if we can tell the size of the packed - -- record in the front end. Packed_Size_Known is True if so far - -- we can figure out the size. It is initialized to True for a - -- packed record, unless the record has discriminants or atomic - -- components or independent components. - - -- The reason we eliminate the discriminated case is that - -- we don't know the way the back end lays out discriminated - -- packed records. If Packed_Size_Known is True, then - -- Packed_Size is the size in bits so far. - - Packed_Size_Known : Boolean := - Is_Packed (T) - and then not Has_Discriminants (T) - and then not Has_Atomic_Components (T) - and then not Has_Independent_Components (T); - - Packed_Size : Uint := Uint_0; - -- SIze in bis so far - - begin - -- Test for variant part present - - if Has_Discriminants (T) - and then Present (Parent (T)) - and then Nkind (Parent (T)) = N_Full_Type_Declaration - and then Nkind (Type_Definition (Parent (T))) = - N_Record_Definition - and then not Null_Present (Type_Definition (Parent (T))) - and then Present (Variant_Part - (Component_List (Type_Definition (Parent (T))))) - then - -- If variant part is present, and type is unconstrained, - -- then we must have defaulted discriminants, or a size - -- clause must be present for the type, or else the size - -- is definitely not known at compile time. - - if not Is_Constrained (T) - and then - No (Discriminant_Default_Value (First_Discriminant (T))) - and then Unknown_RM_Size (T) - then - return False; - end if; - end if; - - -- Loop through components - - Comp := First_Component_Or_Discriminant (T); - while Present (Comp) loop - Ctyp := Etype (Comp); - - -- We do not know the packed size if there is a component - -- clause present (we possibly could, but this would only - -- help in the case of a record with partial rep clauses. - -- That's because in the case of full rep clauses, the - -- size gets figured out anyway by a different circuit). - - if Present (Component_Clause (Comp)) then - Packed_Size_Known := False; - end if; - - -- We do not know the packed size if we have a by reference - -- type, or an atomic type or an atomic component. - - if Is_Atomic (Ctyp) - or else Is_Atomic (Comp) - or else Is_By_Reference_Type (Ctyp) - then - Packed_Size_Known := False; - end if; - - -- We need to identify a component that is an array where - -- the index type is an enumeration type with non-standard - -- representation, and some bound of the type depends on a - -- discriminant. - - -- This is because gigi computes the size by doing a - -- substitution of the appropriate discriminant value in - -- the size expression for the base type, and gigi is not - -- clever enough to evaluate the resulting expression (which - -- involves a call to rep_to_pos) at compile time. - - -- It would be nice if gigi would either recognize that - -- this expression can be computed at compile time, or - -- alternatively figured out the size from the subtype - -- directly, where all the information is at hand ??? - - if Is_Array_Type (Etype (Comp)) - and then Present (Packed_Array_Type (Etype (Comp))) - then - declare - Ocomp : constant Entity_Id := - Original_Record_Component (Comp); - OCtyp : constant Entity_Id := Etype (Ocomp); - Ind : Node_Id; - Indtyp : Entity_Id; - Lo, Hi : Node_Id; - - begin - Ind := First_Index (OCtyp); - while Present (Ind) loop - Indtyp := Etype (Ind); - - if Is_Enumeration_Type (Indtyp) - and then Has_Non_Standard_Rep (Indtyp) - then - Lo := Type_Low_Bound (Indtyp); - Hi := Type_High_Bound (Indtyp); - - if Is_Entity_Name (Lo) - and then Ekind (Entity (Lo)) = E_Discriminant - then - return False; - - elsif Is_Entity_Name (Hi) - and then Ekind (Entity (Hi)) = E_Discriminant - then - return False; - end if; - end if; - - Next_Index (Ind); - end loop; - end; - end if; - - -- Clearly size of record is not known if the size of one of - -- the components is not known. - - if not Size_Known (Ctyp) then - return False; - end if; - - -- Accumulate packed size if possible - - if Packed_Size_Known then - - -- We can only deal with elementary types, since for - -- non-elementary components, alignment enters into the - -- picture, and we don't know enough to handle proper - -- alignment in this context. Packed arrays count as - -- elementary if the representation is a modular type. - - if Is_Elementary_Type (Ctyp) - or else (Is_Array_Type (Ctyp) - and then Present (Packed_Array_Type (Ctyp)) - and then Is_Modular_Integer_Type - (Packed_Array_Type (Ctyp))) - then - -- Packed size unknown if we have an atomic type - -- or a by reference type, since the back end - -- knows how these are layed out. - - if Is_Atomic (Ctyp) - or else Is_By_Reference_Type (Ctyp) - then - Packed_Size_Known := False; - - -- If RM_Size is known and static, then we can keep - -- accumulating the packed size - - elsif Known_Static_RM_Size (Ctyp) then - - -- A little glitch, to be removed sometime ??? - -- gigi does not understand zero sizes yet. - - if RM_Size (Ctyp) = Uint_0 then - Packed_Size_Known := False; - - -- Normal case where we can keep accumulating the - -- packed array size. - - else - Packed_Size := Packed_Size + RM_Size (Ctyp); - end if; - - -- If we have a field whose RM_Size is not known then - -- we can't figure out the packed size here. - - else - Packed_Size_Known := False; - end if; - - -- If we have a non-elementary type we can't figure out - -- the packed array size (alignment issues). - - else - Packed_Size_Known := False; - end if; - end if; - - Next_Component_Or_Discriminant (Comp); - end loop; - - if Packed_Size_Known then - Set_Small_Size (T, Packed_Size); - end if; - - return True; - end; - - -- All other cases, size not known at compile time - - else - return False; - end if; - end Size_Known; - - ------------------------------------- - -- Static_Discriminated_Components -- - ------------------------------------- - - function Static_Discriminated_Components - (T : Entity_Id) return Boolean - is - Constraint : Elmt_Id; - - begin - if Has_Discriminants (T) - and then Present (Discriminant_Constraint (T)) - and then Present (First_Component (T)) - then - Constraint := First_Elmt (Discriminant_Constraint (T)); - while Present (Constraint) loop - if not Compile_Time_Known_Value (Node (Constraint)) then - return False; - end if; - - Next_Elmt (Constraint); - end loop; - end if; - - return True; - end Static_Discriminated_Components; - - -- Start of processing for Check_Compile_Time_Size - - begin - Set_Size_Known_At_Compile_Time (T, Size_Known (T)); - end Check_Compile_Time_Size; - - ----------------------------------- - -- Check_Component_Storage_Order -- - ----------------------------------- - - procedure Check_Component_Storage_Order - (Encl_Type : Entity_Id; - Comp : Entity_Id) - is - Comp_Type : Entity_Id; - Comp_Def : Node_Id; - Err_Node : Node_Id; - ADC : Node_Id; - - Comp_Byte_Aligned : Boolean; - -- Set True for the record case, when Comp starts on a byte boundary - -- (in which case it is allowed to have different storage order). - - begin - -- Record case - - if Present (Comp) then - Err_Node := Comp; - Comp_Type := Etype (Comp); - - if Is_Tag (Comp) then - Comp_Def := Empty; - Comp_Byte_Aligned := True; - - else - Comp_Def := Component_Definition (Parent (Comp)); - Comp_Byte_Aligned := - Present (Component_Clause (Comp)) - and then - Normalized_First_Bit (Comp) mod System_Storage_Unit = 0; - end if; - - -- Array case - - else - Err_Node := Encl_Type; - Comp_Type := Component_Type (Encl_Type); - Comp_Def := Component_Definition - (Type_Definition (Declaration_Node (Encl_Type))); - - Comp_Byte_Aligned := False; - end if; - - -- Note: the Reverse_Storage_Order flag is set on the base type, but - -- the attribute definition clause is attached to the first subtype. - - Comp_Type := Base_Type (Comp_Type); - ADC := Get_Attribute_Definition_Clause - (First_Subtype (Comp_Type), - Attribute_Scalar_Storage_Order); - - if Is_Record_Type (Comp_Type) or else Is_Array_Type (Comp_Type) then - if Present (Comp) and then Chars (Comp) = Name_uParent then - if Reverse_Storage_Order (Encl_Type) - /= - Reverse_Storage_Order (Comp_Type) - then - Error_Msg_N - ("record extension must have same scalar storage order as " - & "parent", Err_Node); - end if; - - elsif No (ADC) then - Error_Msg_N ("nested composite must have explicit scalar " - & "storage order", Err_Node); - - elsif (Reverse_Storage_Order (Encl_Type) - /= - Reverse_Storage_Order (Comp_Type)) - and then not Comp_Byte_Aligned - then - Error_Msg_N - ("type of non-byte-aligned component must have same scalar " - & "storage order as enclosing composite", Err_Node); - end if; - - elsif Present (Comp_Def) and then Aliased_Present (Comp_Def) then - Error_Msg_N - ("aliased component not permitted for type with " - & "explicit Scalar_Storage_Order", Err_Node); - end if; - end Check_Component_Storage_Order; - - ----------------------------- - -- Check_Debug_Info_Needed -- - ----------------------------- - - procedure Check_Debug_Info_Needed (T : Entity_Id) is - begin - if Debug_Info_Off (T) then - return; - - elsif Comes_From_Source (T) - or else Debug_Generated_Code - or else Debug_Flag_VV - or else Needs_Debug_Info (T) - then - Set_Debug_Info_Needed (T); - end if; - end Check_Debug_Info_Needed; - - ---------------------------- - -- Check_Strict_Alignment -- - ---------------------------- - - procedure Check_Strict_Alignment (E : Entity_Id) is - Comp : Entity_Id; - - begin - if Is_Tagged_Type (E) or else Is_Concurrent_Type (E) then - Set_Strict_Alignment (E); - - elsif Is_Array_Type (E) then - Set_Strict_Alignment (E, Strict_Alignment (Component_Type (E))); - - elsif Is_Record_Type (E) then - if Is_Limited_Record (E) then - Set_Strict_Alignment (E); - return; - end if; - - Comp := First_Component (E); - while Present (Comp) loop - if not Is_Type (Comp) - and then (Strict_Alignment (Etype (Comp)) - or else Is_Aliased (Comp)) - then - Set_Strict_Alignment (E); - return; - end if; - - Next_Component (Comp); - end loop; - end if; - end Check_Strict_Alignment; - - ------------------------- - -- Check_Unsigned_Type -- - ------------------------- - - procedure Check_Unsigned_Type (E : Entity_Id) is - Ancestor : Entity_Id; - Lo_Bound : Node_Id; - Btyp : Entity_Id; - - begin - if not Is_Discrete_Or_Fixed_Point_Type (E) then - return; - end if; - - -- Do not attempt to analyze case where range was in error - - if No (Scalar_Range (E)) - or else Error_Posted (Scalar_Range (E)) - then - return; - end if; - - -- The situation that is non trivial is something like - - -- subtype x1 is integer range -10 .. +10; - -- subtype x2 is x1 range 0 .. V1; - -- subtype x3 is x2 range V2 .. V3; - -- subtype x4 is x3 range V4 .. V5; - - -- where Vn are variables. Here the base type is signed, but we still - -- know that x4 is unsigned because of the lower bound of x2. - - -- The only way to deal with this is to look up the ancestor chain - - Ancestor := E; - loop - if Ancestor = Any_Type or else Etype (Ancestor) = Any_Type then - return; - end if; - - Lo_Bound := Type_Low_Bound (Ancestor); - - if Compile_Time_Known_Value (Lo_Bound) then - - if Expr_Rep_Value (Lo_Bound) >= 0 then - Set_Is_Unsigned_Type (E, True); - end if; - - return; - - else - Ancestor := Ancestor_Subtype (Ancestor); - - -- If no ancestor had a static lower bound, go to base type - - if No (Ancestor) then - - -- Note: the reason we still check for a compile time known - -- value for the base type is that at least in the case of - -- generic formals, we can have bounds that fail this test, - -- and there may be other cases in error situations. - - Btyp := Base_Type (E); - - if Btyp = Any_Type or else Etype (Btyp) = Any_Type then - return; - end if; - - Lo_Bound := Type_Low_Bound (Base_Type (E)); - - if Compile_Time_Known_Value (Lo_Bound) - and then Expr_Rep_Value (Lo_Bound) >= 0 - then - Set_Is_Unsigned_Type (E, True); - end if; - - return; - end if; - end if; - end loop; - end Check_Unsigned_Type; - - ------------------------- - -- Is_Atomic_Aggregate -- - ------------------------- - - function Is_Atomic_Aggregate - (E : Entity_Id; - Typ : Entity_Id) return Boolean - is - Loc : constant Source_Ptr := Sloc (E); - New_N : Node_Id; - Par : Node_Id; - Temp : Entity_Id; - - begin - Par := Parent (E); - - -- Array may be qualified, so find outer context - - if Nkind (Par) = N_Qualified_Expression then - Par := Parent (Par); - end if; - - if Nkind_In (Par, N_Object_Declaration, N_Assignment_Statement) - and then Comes_From_Source (Par) - then - Temp := Make_Temporary (Loc, 'T', E); - New_N := - Make_Object_Declaration (Loc, - Defining_Identifier => Temp, - Object_Definition => New_Occurrence_Of (Typ, Loc), - Expression => Relocate_Node (E)); - Insert_Before (Par, New_N); - Analyze (New_N); - - Set_Expression (Par, New_Occurrence_Of (Temp, Loc)); - return True; - - else - return False; - end if; - end Is_Atomic_Aggregate; - - ---------------- - -- Freeze_All -- - ---------------- - - -- Note: the easy coding for this procedure would be to just build a - -- single list of freeze nodes and then insert them and analyze them - -- all at once. This won't work, because the analysis of earlier freeze - -- nodes may recursively freeze types which would otherwise appear later - -- on in the freeze list. So we must analyze and expand the freeze nodes - -- as they are generated. - - procedure Freeze_All (From : Entity_Id; After : in out Node_Id) is - E : Entity_Id; - Decl : Node_Id; - - procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id); - -- This is the internal recursive routine that does freezing of entities - -- (but NOT the analysis of default expressions, which should not be - -- recursive, we don't want to analyze those till we are sure that ALL - -- the types are frozen). - - -------------------- - -- Freeze_All_Ent -- - -------------------- - - procedure Freeze_All_Ent (From : Entity_Id; After : in out Node_Id) is - E : Entity_Id; - Flist : List_Id; - Lastn : Node_Id; - - procedure Process_Flist; - -- If freeze nodes are present, insert and analyze, and reset cursor - -- for next insertion. - - ------------------- - -- Process_Flist -- - ------------------- - - procedure Process_Flist is - begin - if Is_Non_Empty_List (Flist) then - Lastn := Next (After); - Insert_List_After_And_Analyze (After, Flist); - - if Present (Lastn) then - After := Prev (Lastn); - else - After := Last (List_Containing (After)); - end if; - end if; - end Process_Flist; - - -- Start or processing for Freeze_All_Ent - - begin - E := From; - while Present (E) loop - - -- If the entity is an inner package which is not a package - -- renaming, then its entities must be frozen at this point. Note - -- that such entities do NOT get frozen at the end of the nested - -- package itself (only library packages freeze). - - -- Same is true for task declarations, where anonymous records - -- created for entry parameters must be frozen. - - if Ekind (E) = E_Package - and then No (Renamed_Object (E)) - and then not Is_Child_Unit (E) - and then not Is_Frozen (E) - then - Push_Scope (E); - Install_Visible_Declarations (E); - Install_Private_Declarations (E); - - Freeze_All (First_Entity (E), After); - - End_Package_Scope (E); - - if Is_Generic_Instance (E) - and then Has_Delayed_Freeze (E) - then - Set_Has_Delayed_Freeze (E, False); - Expand_N_Package_Declaration (Unit_Declaration_Node (E)); - end if; - - elsif Ekind (E) in Task_Kind - and then - (Nkind (Parent (E)) = N_Task_Type_Declaration - or else - Nkind (Parent (E)) = N_Single_Task_Declaration) - then - Push_Scope (E); - Freeze_All (First_Entity (E), After); - End_Scope; - - -- For a derived tagged type, we must ensure that all the - -- primitive operations of the parent have been frozen, so that - -- their addresses will be in the parent's dispatch table at the - -- point it is inherited. - - elsif Ekind (E) = E_Record_Type - and then Is_Tagged_Type (E) - and then Is_Tagged_Type (Etype (E)) - and then Is_Derived_Type (E) - then - declare - Prim_List : constant Elist_Id := - Primitive_Operations (Etype (E)); - - Prim : Elmt_Id; - Subp : Entity_Id; - - begin - Prim := First_Elmt (Prim_List); - while Present (Prim) loop - Subp := Node (Prim); - - if Comes_From_Source (Subp) - and then not Is_Frozen (Subp) - then - Flist := Freeze_Entity (Subp, After); - Process_Flist; - end if; - - Next_Elmt (Prim); - end loop; - end; - end if; - - if not Is_Frozen (E) then - Flist := Freeze_Entity (E, After); - Process_Flist; - - -- If already frozen, and there are delayed aspects, this is where - -- we do the visibility check for these aspects (see Sem_Ch13 spec - -- for a description of how we handle aspect visibility). - - elsif Has_Delayed_Aspects (E) then - - -- Retrieve the visibility to the discriminants in order to - -- analyze properly the aspects. - - Push_Scope_And_Install_Discriminants (E); - - declare - Ritem : Node_Id; - - begin - Ritem := First_Rep_Item (E); - while Present (Ritem) loop - if Nkind (Ritem) = N_Aspect_Specification - and then Entity (Ritem) = E - and then Is_Delayed_Aspect (Ritem) - then - Check_Aspect_At_End_Of_Declarations (Ritem); - end if; - - Ritem := Next_Rep_Item (Ritem); - end loop; - end; - - Uninstall_Discriminants_And_Pop_Scope (E); - end if; - - -- If an incomplete type is still not frozen, this may be a - -- premature freezing because of a body declaration that follows. - -- Indicate where the freezing took place. Freezing will happen - -- if the body comes from source, but not if it is internally - -- generated, for example as the body of a type invariant. - - -- If the freezing is caused by the end of the current declarative - -- part, it is a Taft Amendment type, and there is no error. - - if not Is_Frozen (E) - and then Ekind (E) = E_Incomplete_Type - then - declare - Bod : constant Node_Id := Next (After); - - begin - -- The presence of a body freezes all entities previously - -- declared in the current list of declarations, but this - -- does not apply if the body does not come from source. - -- A type invariant is transformed into a subprogram body - -- which is placed at the end of the private part of the - -- current package, but this body does not freeze incomplete - -- types that may be declared in this private part. - - if (Nkind_In (Bod, N_Subprogram_Body, - N_Entry_Body, - N_Package_Body, - N_Protected_Body, - N_Task_Body) - or else Nkind (Bod) in N_Body_Stub) - and then - List_Containing (After) = List_Containing (Parent (E)) - and then Comes_From_Source (Bod) - then - Error_Msg_Sloc := Sloc (Next (After)); - Error_Msg_NE - ("type& is frozen# before its full declaration", - Parent (E), E); - end if; - end; - end if; - - Next_Entity (E); - end loop; - end Freeze_All_Ent; - - -- Start of processing for Freeze_All - - begin - Freeze_All_Ent (From, After); - - -- Now that all types are frozen, we can deal with default expressions - -- that require us to build a default expression functions. This is the - -- point at which such functions are constructed (after all types that - -- might be used in such expressions have been frozen). - - -- For subprograms that are renaming_as_body, we create the wrapper - -- bodies as needed. - - -- We also add finalization chains to access types whose designated - -- types are controlled. This is normally done when freezing the type, - -- but this misses recursive type definitions where the later members - -- of the recursion introduce controlled components. - - -- Loop through entities - - E := From; - while Present (E) loop - if Is_Subprogram (E) then - - if not Default_Expressions_Processed (E) then - Process_Default_Expressions (E, After); - end if; - - if not Has_Completion (E) then - Decl := Unit_Declaration_Node (E); - - if Nkind (Decl) = N_Subprogram_Renaming_Declaration then - if Error_Posted (Decl) then - Set_Has_Completion (E); - else - Build_And_Analyze_Renamed_Body (Decl, E, After); - end if; - - elsif Nkind (Decl) = N_Subprogram_Declaration - and then Present (Corresponding_Body (Decl)) - and then - Nkind (Unit_Declaration_Node (Corresponding_Body (Decl))) - = N_Subprogram_Renaming_Declaration - then - Build_And_Analyze_Renamed_Body - (Decl, Corresponding_Body (Decl), After); - end if; - end if; - - elsif Ekind (E) in Task_Kind - and then - (Nkind (Parent (E)) = N_Task_Type_Declaration - or else - Nkind (Parent (E)) = N_Single_Task_Declaration) - then - declare - Ent : Entity_Id; - - begin - Ent := First_Entity (E); - while Present (Ent) loop - if Is_Entry (Ent) - and then not Default_Expressions_Processed (Ent) - then - Process_Default_Expressions (Ent, After); - end if; - - Next_Entity (Ent); - end loop; - end; - - -- We add finalization masters to access types whose designated types - -- require finalization. This is normally done when freezing the - -- type, but this misses recursive type definitions where the later - -- members of the recursion introduce controlled components (such as - -- can happen when incomplete types are involved), as well cases - -- where a component type is private and the controlled full type - -- occurs after the access type is frozen. Cases that don't need a - -- finalization master are generic formal types (the actual type will - -- have it) and types with Java and CIL conventions, since those are - -- used for API bindings. (Are there any other cases that should be - -- excluded here???) - - elsif Is_Access_Type (E) - and then Comes_From_Source (E) - and then not Is_Generic_Type (E) - and then Needs_Finalization (Designated_Type (E)) - then - Build_Finalization_Master (E); - end if; - - Next_Entity (E); - end loop; - end Freeze_All; - - ----------------------- - -- Freeze_And_Append -- - ----------------------- - - procedure Freeze_And_Append - (Ent : Entity_Id; - N : Node_Id; - Result : in out List_Id) - is - L : constant List_Id := Freeze_Entity (Ent, N); - begin - if Is_Non_Empty_List (L) then - if Result = No_List then - Result := L; - else - Append_List (L, Result); - end if; - end if; - end Freeze_And_Append; - - ------------------- - -- Freeze_Before -- - ------------------- - - procedure Freeze_Before (N : Node_Id; T : Entity_Id) is - Freeze_Nodes : constant List_Id := Freeze_Entity (T, N); - begin - if Is_Non_Empty_List (Freeze_Nodes) then - Insert_Actions (N, Freeze_Nodes); - end if; - end Freeze_Before; - - ------------------- - -- Freeze_Entity -- - ------------------- - - function Freeze_Entity (E : Entity_Id; N : Node_Id) return List_Id is - Loc : constant Source_Ptr := Sloc (N); - Test_E : Entity_Id := E; - Comp : Entity_Id; - F_Node : Node_Id; - Indx : Node_Id; - Formal : Entity_Id; - Atype : Entity_Id; - - Result : List_Id := No_List; - -- List of freezing actions, left at No_List if none - - Has_Default_Initialization : Boolean := False; - -- This flag gets set to true for a variable with default initialization - - procedure Add_To_Result (N : Node_Id); - -- N is a freezing action to be appended to the Result - - function After_Last_Declaration return Boolean; - -- If Loc is a freeze_entity that appears after the last declaration - -- in the scope, inhibit error messages on late completion. - - procedure Check_Current_Instance (Comp_Decl : Node_Id); - -- Check that an Access or Unchecked_Access attribute with a prefix - -- which is the current instance type can only be applied when the type - -- is limited. - - procedure Check_Suspicious_Modulus (Utype : Entity_Id); - -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit - -- integer literal without an explicit corresponding size clause. The - -- caller has checked that Utype is a modular integer type. - - procedure Freeze_Record_Type (Rec : Entity_Id); - -- Freeze each component, handle some representation clauses, and freeze - -- primitive operations if this is a tagged type. - - ------------------- - -- Add_To_Result -- - ------------------- - - procedure Add_To_Result (N : Node_Id) is - begin - if No (Result) then - Result := New_List (N); - else - Append (N, Result); - end if; - end Add_To_Result; - - ---------------------------- - -- After_Last_Declaration -- - ---------------------------- - - function After_Last_Declaration return Boolean is - Spec : constant Node_Id := Parent (Current_Scope); - begin - if Nkind (Spec) = N_Package_Specification then - if Present (Private_Declarations (Spec)) then - return Loc >= Sloc (Last (Private_Declarations (Spec))); - elsif Present (Visible_Declarations (Spec)) then - return Loc >= Sloc (Last (Visible_Declarations (Spec))); - else - return False; - end if; - else - return False; - end if; - end After_Last_Declaration; - - ---------------------------- - -- Check_Current_Instance -- - ---------------------------- - - procedure Check_Current_Instance (Comp_Decl : Node_Id) is - - function Is_Aliased_View_Of_Type (Typ : Entity_Id) return Boolean; - -- Determine whether Typ is compatible with the rules for aliased - -- views of types as defined in RM 3.10 in the various dialects. - - function Process (N : Node_Id) return Traverse_Result; - -- Process routine to apply check to given node - - ----------------------------- - -- Is_Aliased_View_Of_Type -- - ----------------------------- - - function Is_Aliased_View_Of_Type (Typ : Entity_Id) return Boolean is - Typ_Decl : constant Node_Id := Parent (Typ); - - begin - -- Common case - - if Nkind (Typ_Decl) = N_Full_Type_Declaration - and then Limited_Present (Type_Definition (Typ_Decl)) - then - return True; - - -- The following paragraphs describe what a legal aliased view of - -- a type is in the various dialects of Ada. - - -- Ada 95 - - -- The current instance of a limited type, and a formal parameter - -- or generic formal object of a tagged type. - - -- Ada 95 limited type - -- * Type with reserved word "limited" - -- * A protected or task type - -- * A composite type with limited component - - elsif Ada_Version <= Ada_95 then - return Is_Limited_Type (Typ); - - -- Ada 2005 - - -- The current instance of a limited tagged type, a protected - -- type, a task type, or a type that has the reserved word - -- "limited" in its full definition ... a formal parameter or - -- generic formal object of a tagged type. - - -- Ada 2005 limited type - -- * Type with reserved word "limited", "synchronized", "task" - -- or "protected" - -- * A composite type with limited component - -- * A derived type whose parent is a non-interface limited type - - elsif Ada_Version = Ada_2005 then - return - (Is_Limited_Type (Typ) and then Is_Tagged_Type (Typ)) - or else - (Is_Derived_Type (Typ) - and then not Is_Interface (Etype (Typ)) - and then Is_Limited_Type (Etype (Typ))); - - -- Ada 2012 and beyond - - -- The current instance of an immutably limited type ... a formal - -- parameter or generic formal object of a tagged type. - - -- Ada 2012 limited type - -- * Type with reserved word "limited", "synchronized", "task" - -- or "protected" - -- * A composite type with limited component - -- * A derived type whose parent is a non-interface limited type - -- * An incomplete view - - -- Ada 2012 immutably limited type - -- * Explicitly limited record type - -- * Record extension with "limited" present - -- * Non-formal limited private type that is either tagged - -- or has at least one access discriminant with a default - -- expression - -- * Task type, protected type or synchronized interface - -- * Type derived from immutably limited type - - else - return - Is_Immutably_Limited_Type (Typ) - or else Is_Incomplete_Type (Typ); - end if; - end Is_Aliased_View_Of_Type; - - ------------- - -- Process -- - ------------- - - function Process (N : Node_Id) return Traverse_Result is - begin - case Nkind (N) is - when N_Attribute_Reference => - if (Attribute_Name (N) = Name_Access - or else - Attribute_Name (N) = Name_Unchecked_Access) - and then Is_Entity_Name (Prefix (N)) - and then Is_Type (Entity (Prefix (N))) - and then Entity (Prefix (N)) = E - then - Error_Msg_N - ("current instance must be a limited type", Prefix (N)); - return Abandon; - else - return OK; - end if; - - when others => return OK; - end case; - end Process; - - procedure Traverse is new Traverse_Proc (Process); - - -- Local variables - - Rec_Type : constant Entity_Id := - Scope (Defining_Identifier (Comp_Decl)); - - -- Start of processing for Check_Current_Instance - - begin - if not Is_Aliased_View_Of_Type (Rec_Type) then - Traverse (Comp_Decl); - end if; - end Check_Current_Instance; - - ------------------------------ - -- Check_Suspicious_Modulus -- - ------------------------------ - - procedure Check_Suspicious_Modulus (Utype : Entity_Id) is - Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype)); - - begin - if not Warn_On_Suspicious_Modulus_Value then - return; - end if; - - if Nkind (Decl) = N_Full_Type_Declaration then - declare - Tdef : constant Node_Id := Type_Definition (Decl); - - begin - if Nkind (Tdef) = N_Modular_Type_Definition then - declare - Modulus : constant Node_Id := - Original_Node (Expression (Tdef)); - - begin - if Nkind (Modulus) = N_Integer_Literal then - declare - Modv : constant Uint := Intval (Modulus); - Sizv : constant Uint := RM_Size (Utype); - - begin - -- First case, modulus and size are the same. This - -- happens if you have something like mod 32, with - -- an explicit size of 32, this is for sure a case - -- where the warning is given, since it is seems - -- very unlikely that someone would want e.g. a - -- five bit type stored in 32 bits. It is much - -- more likely they wanted a 32-bit type. - - if Modv = Sizv then - null; - - -- Second case, the modulus is 32 or 64 and no - -- size clause is present. This is a less clear - -- case for giving the warning, but in the case - -- of 32/64 (5-bit or 6-bit types) these seem rare - -- enough that it is a likely error (and in any - -- case using 2**5 or 2**6 in these cases seems - -- clearer. We don't include 8 or 16 here, simply - -- because in practice 3-bit and 4-bit types are - -- more common and too many false positives if - -- we warn in these cases. - - elsif not Has_Size_Clause (Utype) - and then (Modv = Uint_32 or else Modv = Uint_64) - then - null; - - -- No warning needed - - else - return; - end if; - - -- If we fall through, give warning - - Error_Msg_Uint_1 := Modv; - Error_Msg_N - ("?M?2 '*'*^' may have been intended here", - Modulus); - end; - end if; - end; - end if; - end; - end if; - end Check_Suspicious_Modulus; - - ------------------------ - -- Freeze_Record_Type -- - ------------------------ - - procedure Freeze_Record_Type (Rec : Entity_Id) is - Comp : Entity_Id; - IR : Node_Id; - ADC : Node_Id; - Prev : Entity_Id; - - Junk : Boolean; - pragma Warnings (Off, Junk); - - Rec_Pushed : Boolean := False; - -- Set True if the record type scope Rec has been pushed on the scope - -- stack. Needed for the analysis of delayed aspects specified to the - -- components of Rec. - - Unplaced_Component : Boolean := False; - -- Set True if we find at least one component with no component - -- clause (used to warn about useless Pack pragmas). - - Placed_Component : Boolean := False; - -- Set True if we find at least one component with a component - -- clause (used to warn about useless Bit_Order pragmas, and also - -- to detect cases where Implicit_Packing may have an effect). - - All_Scalar_Components : Boolean := True; - -- Set False if we encounter a component of a non-scalar type - - Scalar_Component_Total_RM_Size : Uint := Uint_0; - Scalar_Component_Total_Esize : Uint := Uint_0; - -- Accumulates total RM_Size values and total Esize values of all - -- scalar components. Used for processing of Implicit_Packing. - - function Check_Allocator (N : Node_Id) return Node_Id; - -- If N is an allocator, possibly wrapped in one or more level of - -- qualified expression(s), return the inner allocator node, else - -- return Empty. - - procedure Check_Itype (Typ : Entity_Id); - -- If the component subtype is an access to a constrained subtype of - -- an already frozen type, make the subtype frozen as well. It might - -- otherwise be frozen in the wrong scope, and a freeze node on - -- subtype has no effect. Similarly, if the component subtype is a - -- regular (not protected) access to subprogram, set the anonymous - -- subprogram type to frozen as well, to prevent an out-of-scope - -- freeze node at some eventual point of call. Protected operations - -- are handled elsewhere. - - --------------------- - -- Check_Allocator -- - --------------------- - - function Check_Allocator (N : Node_Id) return Node_Id is - Inner : Node_Id; - begin - Inner := N; - loop - if Nkind (Inner) = N_Allocator then - return Inner; - elsif Nkind (Inner) = N_Qualified_Expression then - Inner := Expression (Inner); - else - return Empty; - end if; - end loop; - end Check_Allocator; - - ----------------- - -- Check_Itype -- - ----------------- - - procedure Check_Itype (Typ : Entity_Id) is - Desig : constant Entity_Id := Designated_Type (Typ); - - begin - if not Is_Frozen (Desig) - and then Is_Frozen (Base_Type (Desig)) - then - Set_Is_Frozen (Desig); - - -- In addition, add an Itype_Reference to ensure that the - -- access subtype is elaborated early enough. This cannot be - -- done if the subtype may depend on discriminants. - - if Ekind (Comp) = E_Component - and then Is_Itype (Etype (Comp)) - and then not Has_Discriminants (Rec) - then - IR := Make_Itype_Reference (Sloc (Comp)); - Set_Itype (IR, Desig); - Add_To_Result (IR); - end if; - - elsif Ekind (Typ) = E_Anonymous_Access_Subprogram_Type - and then Convention (Desig) /= Convention_Protected - then - Set_Is_Frozen (Desig); - end if; - end Check_Itype; - - -- Start of processing for Freeze_Record_Type - - begin - -- Deal with delayed aspect specifications for components. The - -- analysis of the aspect is required to be delayed to the freeze - -- point, thus we analyze the pragma or attribute definition - -- clause in the tree at this point. We also analyze the aspect - -- specification node at the freeze point when the aspect doesn't - -- correspond to pragma/attribute definition clause. - - Comp := First_Entity (Rec); - while Present (Comp) loop - if Ekind (Comp) = E_Component - and then Has_Delayed_Aspects (Comp) - then - if not Rec_Pushed then - Push_Scope (Rec); - Rec_Pushed := True; - - -- The visibility to the discriminants must be restored in - -- order to properly analyze the aspects. - - if Has_Discriminants (Rec) then - Install_Discriminants (Rec); - end if; - end if; - - Analyze_Aspects_At_Freeze_Point (Comp); - end if; - - Next_Entity (Comp); - end loop; - - -- Pop the scope if Rec scope has been pushed on the scope stack - -- during the delayed aspect analysis process. - - if Rec_Pushed then - if Has_Discriminants (Rec) then - Uninstall_Discriminants (Rec); - end if; - - Pop_Scope; - end if; - - -- Freeze components and embedded subtypes - - Comp := First_Entity (Rec); - Prev := Empty; - while Present (Comp) loop - - -- Handle the component and discriminant case - - if Ekind_In (Comp, E_Component, E_Discriminant) then - declare - CC : constant Node_Id := Component_Clause (Comp); - - begin - -- Freezing a record type freezes the type of each of its - -- components. However, if the type of the component is - -- part of this record, we do not want or need a separate - -- Freeze_Node. Note that Is_Itype is wrong because that's - -- also set in private type cases. We also can't check for - -- the Scope being exactly Rec because of private types and - -- record extensions. - - if Is_Itype (Etype (Comp)) - and then Is_Record_Type (Underlying_Type - (Scope (Etype (Comp)))) - then - Undelay_Type (Etype (Comp)); - end if; - - Freeze_And_Append (Etype (Comp), N, Result); - - -- Check for error of component clause given for variable - -- sized type. We have to delay this test till this point, - -- since the component type has to be frozen for us to know - -- if it is variable length. We omit this test in a generic - -- context, it will be applied at instantiation time. - - -- We also omit this test in CodePeer mode, since we do not - -- have sufficient info on size and representation clauses. - - if Present (CC) then - Placed_Component := True; - - if Inside_A_Generic then - null; - - elsif CodePeer_Mode then - null; - - elsif not - Size_Known_At_Compile_Time - (Underlying_Type (Etype (Comp))) - then - Error_Msg_N - ("component clause not allowed for variable " & - "length component", CC); - end if; - - else - Unplaced_Component := True; - end if; - - -- Case of component requires byte alignment - - if Must_Be_On_Byte_Boundary (Etype (Comp)) then - - -- Set the enclosing record to also require byte align - - Set_Must_Be_On_Byte_Boundary (Rec); - - -- Check for component clause that is inconsistent with - -- the required byte boundary alignment. - - if Present (CC) - and then Normalized_First_Bit (Comp) mod - System_Storage_Unit /= 0 - then - Error_Msg_N - ("component & must be byte aligned", - Component_Name (Component_Clause (Comp))); - end if; - end if; - end; - end if; - - -- Gather data for possible Implicit_Packing later. Note that at - -- this stage we might be dealing with a real component, or with - -- an implicit subtype declaration. - - if not Is_Scalar_Type (Etype (Comp)) then - All_Scalar_Components := False; - else - Scalar_Component_Total_RM_Size := - Scalar_Component_Total_RM_Size + RM_Size (Etype (Comp)); - Scalar_Component_Total_Esize := - Scalar_Component_Total_Esize + Esize (Etype (Comp)); - end if; - - -- If the component is an Itype with Delayed_Freeze and is either - -- a record or array subtype and its base type has not yet been - -- frozen, we must remove this from the entity list of this record - -- and put it on the entity list of the scope of its base type. - -- Note that we know that this is not the type of a component - -- since we cleared Has_Delayed_Freeze for it in the previous - -- loop. Thus this must be the Designated_Type of an access type, - -- which is the type of a component. - - if Is_Itype (Comp) - and then Is_Type (Scope (Comp)) - and then Is_Composite_Type (Comp) - and then Base_Type (Comp) /= Comp - and then Has_Delayed_Freeze (Comp) - and then not Is_Frozen (Base_Type (Comp)) - then - declare - Will_Be_Frozen : Boolean := False; - S : Entity_Id; - - begin - -- We have a pretty bad kludge here. Suppose Rec is subtype - -- being defined in a subprogram that's created as part of - -- the freezing of Rec'Base. In that case, we know that - -- Comp'Base must have already been frozen by the time we - -- get to elaborate this because Gigi doesn't elaborate any - -- bodies until it has elaborated all of the declarative - -- part. But Is_Frozen will not be set at this point because - -- we are processing code in lexical order. - - -- We detect this case by going up the Scope chain of Rec - -- and seeing if we have a subprogram scope before reaching - -- the top of the scope chain or that of Comp'Base. If we - -- do, then mark that Comp'Base will actually be frozen. If - -- so, we merely undelay it. - - S := Scope (Rec); - while Present (S) loop - if Is_Subprogram (S) then - Will_Be_Frozen := True; - exit; - elsif S = Scope (Base_Type (Comp)) then - exit; - end if; - - S := Scope (S); - end loop; - - if Will_Be_Frozen then - Undelay_Type (Comp); - else - if Present (Prev) then - Set_Next_Entity (Prev, Next_Entity (Comp)); - else - Set_First_Entity (Rec, Next_Entity (Comp)); - end if; - - -- Insert in entity list of scope of base type (which - -- must be an enclosing scope, because still unfrozen). - - Append_Entity (Comp, Scope (Base_Type (Comp))); - end if; - end; - - -- If the component is an access type with an allocator as default - -- value, the designated type will be frozen by the corresponding - -- expression in init_proc. In order to place the freeze node for - -- the designated type before that for the current record type, - -- freeze it now. - - -- Same process if the component is an array of access types, - -- initialized with an aggregate. If the designated type is - -- private, it cannot contain allocators, and it is premature - -- to freeze the type, so we check for this as well. - - elsif Is_Access_Type (Etype (Comp)) - and then Present (Parent (Comp)) - and then Present (Expression (Parent (Comp))) - then - declare - Alloc : constant Node_Id := - Check_Allocator (Expression (Parent (Comp))); - - begin - if Present (Alloc) then - - -- If component is pointer to a classwide type, freeze - -- the specific type in the expression being allocated. - -- The expression may be a subtype indication, in which - -- case freeze the subtype mark. - - if Is_Class_Wide_Type - (Designated_Type (Etype (Comp))) - then - if Is_Entity_Name (Expression (Alloc)) then - Freeze_And_Append - (Entity (Expression (Alloc)), N, Result); - elsif - Nkind (Expression (Alloc)) = N_Subtype_Indication - then - Freeze_And_Append - (Entity (Subtype_Mark (Expression (Alloc))), - N, Result); - end if; - - elsif Is_Itype (Designated_Type (Etype (Comp))) then - Check_Itype (Etype (Comp)); - - else - Freeze_And_Append - (Designated_Type (Etype (Comp)), N, Result); - end if; - end if; - end; - - elsif Is_Access_Type (Etype (Comp)) - and then Is_Itype (Designated_Type (Etype (Comp))) - then - Check_Itype (Etype (Comp)); - - elsif Is_Array_Type (Etype (Comp)) - and then Is_Access_Type (Component_Type (Etype (Comp))) - and then Present (Parent (Comp)) - and then Nkind (Parent (Comp)) = N_Component_Declaration - and then Present (Expression (Parent (Comp))) - and then Nkind (Expression (Parent (Comp))) = N_Aggregate - and then Is_Fully_Defined - (Designated_Type (Component_Type (Etype (Comp)))) - then - Freeze_And_Append - (Designated_Type - (Component_Type (Etype (Comp))), N, Result); - end if; - - Prev := Comp; - Next_Entity (Comp); - end loop; - - ADC := Get_Attribute_Definition_Clause - (Rec, Attribute_Scalar_Storage_Order); - - if Present (ADC) then - - -- Check compatibility of Scalar_Storage_Order with Bit_Order, if - -- the former is specified. - - if Reverse_Bit_Order (Rec) /= Reverse_Storage_Order (Rec) then - - -- Note: report error on Rec, not on ADC, as ADC may apply to - -- an ancestor type. - - Error_Msg_Sloc := Sloc (ADC); - Error_Msg_N - ("scalar storage order for& specified# inconsistent with " - & "bit order", Rec); - end if; - - -- Warn if there is a Scalar_Storage_Order but no component clause - -- (or pragma Pack). - - if not (Placed_Component or else Is_Packed (Rec)) then - Error_Msg_N - ("??scalar storage order specified but no component clause", - ADC); - end if; - - -- Check attribute on component types - - Comp := First_Component (Rec); - while Present (Comp) loop - Check_Component_Storage_Order (Rec, Comp); - Next_Component (Comp); - end loop; - end if; - - -- Deal with Bit_Order aspect specifying a non-default bit order - - ADC := Get_Attribute_Definition_Clause (Rec, Attribute_Bit_Order); - - if Present (ADC) and then Base_Type (Rec) = Rec then - if not (Placed_Component or else Is_Packed (Rec)) then - Error_Msg_N ("??bit order specification has no effect", ADC); - Error_Msg_N - ("\??since no component clauses were specified", ADC); - - -- Here is where we do the processing for reversed bit order - - elsif Reverse_Bit_Order (Rec) - and then not Reverse_Storage_Order (Rec) - then - Adjust_Record_For_Reverse_Bit_Order (Rec); - - -- Case where we have both an explicit Bit_Order and the same - -- Scalar_Storage_Order: leave record untouched, the back-end - -- will take care of required layout conversions. - - else - null; - - end if; - end if; - - -- Complete error checking on record representation clause (e.g. - -- overlap of components). This is called after adjusting the - -- record for reverse bit order. - - declare - RRC : constant Node_Id := Get_Record_Representation_Clause (Rec); - begin - if Present (RRC) then - Check_Record_Representation_Clause (RRC); - end if; - end; - - -- Set OK_To_Reorder_Components depending on debug flags - - if Is_Base_Type (Rec) and then Convention (Rec) = Convention_Ada then - if (Has_Discriminants (Rec) and then Debug_Flag_Dot_V) - or else - (not Has_Discriminants (Rec) and then Debug_Flag_Dot_R) - then - Set_OK_To_Reorder_Components (Rec); - end if; - end if; - - -- Check for useless pragma Pack when all components placed. We only - -- do this check for record types, not subtypes, since a subtype may - -- have all its components placed, and it still makes perfectly good - -- sense to pack other subtypes or the parent type. We do not give - -- this warning if Optimize_Alignment is set to Space, since the - -- pragma Pack does have an effect in this case (it always resets - -- the alignment to one). - - if Ekind (Rec) = E_Record_Type - and then Is_Packed (Rec) - and then not Unplaced_Component - and then Optimize_Alignment /= 'S' - then - -- Reset packed status. Probably not necessary, but we do it so - -- that there is no chance of the back end doing something strange - -- with this redundant indication of packing. - - Set_Is_Packed (Rec, False); - - -- Give warning if redundant constructs warnings on - - if Warn_On_Redundant_Constructs then - Error_Msg_N -- CODEFIX - ("??pragma Pack has no effect, no unplaced components", - Get_Rep_Pragma (Rec, Name_Pack)); - end if; - end if; - - -- If this is the record corresponding to a remote type, freeze the - -- remote type here since that is what we are semantically freezing. - -- This prevents the freeze node for that type in an inner scope. - - -- Also, Check for controlled components and unchecked unions. - -- Finally, enforce the restriction that access attributes with a - -- current instance prefix can only apply to limited types. - - if Ekind (Rec) = E_Record_Type then - if Present (Corresponding_Remote_Type (Rec)) then - Freeze_And_Append (Corresponding_Remote_Type (Rec), N, Result); - end if; - - Comp := First_Component (Rec); - while Present (Comp) loop - - -- Do not set Has_Controlled_Component on a class-wide - -- equivalent type. See Make_CW_Equivalent_Type. - - if not Is_Class_Wide_Equivalent_Type (Rec) - and then (Has_Controlled_Component (Etype (Comp)) - or else (Chars (Comp) /= Name_uParent - and then Is_Controlled (Etype (Comp))) - or else (Is_Protected_Type (Etype (Comp)) - and then Present - (Corresponding_Record_Type - (Etype (Comp))) - and then Has_Controlled_Component - (Corresponding_Record_Type - (Etype (Comp))))) - then - Set_Has_Controlled_Component (Rec); - end if; - - if Has_Unchecked_Union (Etype (Comp)) then - Set_Has_Unchecked_Union (Rec); - end if; - - -- Scan component declaration for likely misuses of current - -- instance, either in a constraint or a default expression. - - if Has_Per_Object_Constraint (Comp) then - Check_Current_Instance (Parent (Comp)); - end if; - - Next_Component (Comp); - end loop; - end if; - - Set_Component_Alignment_If_Not_Set (Rec); - - -- For first subtypes, check if there are any fixed-point fields with - -- component clauses, where we must check the size. This is not done - -- till the freeze point, since for fixed-point types, we do not know - -- the size until the type is frozen. Similar processing applies to - -- bit packed arrays. - - if Is_First_Subtype (Rec) then - Comp := First_Component (Rec); - while Present (Comp) loop - if Present (Component_Clause (Comp)) - and then (Is_Fixed_Point_Type (Etype (Comp)) - or else - Is_Bit_Packed_Array (Etype (Comp))) - then - Check_Size - (Component_Name (Component_Clause (Comp)), - Etype (Comp), - Esize (Comp), - Junk); - end if; - - Next_Component (Comp); - end loop; - end if; - - -- Generate warning for applying C or C++ convention to a record - -- with discriminants. This is suppressed for the unchecked union - -- case, since the whole point in this case is interface C. We also - -- do not generate this within instantiations, since we will have - -- generated a message on the template. - - if Has_Discriminants (E) - and then not Is_Unchecked_Union (E) - and then (Convention (E) = Convention_C - or else - Convention (E) = Convention_CPP) - and then Comes_From_Source (E) - and then not In_Instance - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (Base_Type (E)) - then - declare - Cprag : constant Node_Id := Get_Rep_Pragma (E, Name_Convention); - A2 : Node_Id; - - begin - if Present (Cprag) then - A2 := Next (First (Pragma_Argument_Associations (Cprag))); - - if Convention (E) = Convention_C then - Error_Msg_N - ("?x?variant record has no direct equivalent in C", - A2); - else - Error_Msg_N - ("?x?variant record has no direct equivalent in C++", - A2); - end if; - - Error_Msg_NE - ("\?x?use of convention for type& is dubious", A2, E); - end if; - end; - end if; - - -- See if Size is too small as is (and implicit packing might help) - - if not Is_Packed (Rec) - - -- No implicit packing if even one component is explicitly placed - - and then not Placed_Component - - -- Must have size clause and all scalar components - - and then Has_Size_Clause (Rec) - and then All_Scalar_Components - - -- Do not try implicit packing on records with discriminants, too - -- complicated, especially in the variant record case. - - and then not Has_Discriminants (Rec) - - -- We can implicitly pack if the specified size of the record is - -- less than the sum of the object sizes (no point in packing if - -- this is not the case). - - and then RM_Size (Rec) < Scalar_Component_Total_Esize - - -- And the total RM size cannot be greater than the specified size - -- since otherwise packing will not get us where we have to be! - - and then RM_Size (Rec) >= Scalar_Component_Total_RM_Size - - -- Never do implicit packing in CodePeer or Alfa modes since - -- we don't do any packing in these modes, since this generates - -- over-complex code that confuses static analysis, and in - -- general, neither CodePeer not GNATprove care about the - -- internal representation of objects. - - and then not (CodePeer_Mode or Alfa_Mode) - then - -- If implicit packing enabled, do it - - if Implicit_Packing then - Set_Is_Packed (Rec); - - -- Otherwise flag the size clause - - else - declare - Sz : constant Node_Id := Size_Clause (Rec); - begin - Error_Msg_NE -- CODEFIX - ("size given for& too small", Sz, Rec); - Error_Msg_N -- CODEFIX - ("\use explicit pragma Pack " - & "or use pragma Implicit_Packing", Sz); - end; - end if; - end if; - end Freeze_Record_Type; - - -- Start of processing for Freeze_Entity - - begin - -- We are going to test for various reasons why this entity need not be - -- frozen here, but in the case of an Itype that's defined within a - -- record, that test actually applies to the record. - - if Is_Itype (E) and then Is_Record_Type (Scope (E)) then - Test_E := Scope (E); - elsif Is_Itype (E) and then Present (Underlying_Type (Scope (E))) - and then Is_Record_Type (Underlying_Type (Scope (E))) - then - Test_E := Underlying_Type (Scope (E)); - end if; - - -- Do not freeze if already frozen since we only need one freeze node - - if Is_Frozen (E) then - return No_List; - - -- It is improper to freeze an external entity within a generic because - -- its freeze node will appear in a non-valid context. The entity will - -- be frozen in the proper scope after the current generic is analyzed. - -- However, aspects must be analyzed because they may be queried later - -- within the generic itself, and the corresponding pragma or attribute - -- definition has not been analyzed yet. - - elsif Inside_A_Generic and then External_Ref_In_Generic (Test_E) then - if Has_Delayed_Aspects (E) then - Analyze_Aspects_At_Freeze_Point (E); - end if; - - return No_List; - - -- AI05-0213: A formal incomplete type does not freeze the actual. In - -- the instance, the same applies to the subtype renaming the actual. - - elsif Is_Private_Type (E) - and then Is_Generic_Actual_Type (E) - and then No (Full_View (Base_Type (E))) - and then Ada_Version >= Ada_2012 - then - return No_List; - - -- Do not freeze a global entity within an inner scope created during - -- expansion. A call to subprogram E within some internal procedure - -- (a stream attribute for example) might require freezing E, but the - -- freeze node must appear in the same declarative part as E itself. - -- The two-pass elaboration mechanism in gigi guarantees that E will - -- be frozen before the inner call is elaborated. We exclude constants - -- from this test, because deferred constants may be frozen early, and - -- must be diagnosed (e.g. in the case of a deferred constant being used - -- in a default expression). If the enclosing subprogram comes from - -- source, or is a generic instance, then the freeze point is the one - -- mandated by the language, and we freeze the entity. A subprogram that - -- is a child unit body that acts as a spec does not have a spec that - -- comes from source, but can only come from source. - - elsif In_Open_Scopes (Scope (Test_E)) - and then Scope (Test_E) /= Current_Scope - and then Ekind (Test_E) /= E_Constant - then - declare - S : Entity_Id; - - begin - S := Current_Scope; - while Present (S) loop - if Is_Overloadable (S) then - if Comes_From_Source (S) - or else Is_Generic_Instance (S) - or else Is_Child_Unit (S) - then - exit; - else - return No_List; - end if; - end if; - - S := Scope (S); - end loop; - end; - - -- Similarly, an inlined instance body may make reference to global - -- entities, but these references cannot be the proper freezing point - -- for them, and in the absence of inlining freezing will take place in - -- their own scope. Normally instance bodies are analyzed after the - -- enclosing compilation, and everything has been frozen at the proper - -- place, but with front-end inlining an instance body is compiled - -- before the end of the enclosing scope, and as a result out-of-order - -- freezing must be prevented. - - elsif Front_End_Inlining - and then In_Instance_Body - and then Present (Scope (Test_E)) - then - declare - S : Entity_Id; - - begin - S := Scope (Test_E); - while Present (S) loop - if Is_Generic_Instance (S) then - exit; - else - S := Scope (S); - end if; - end loop; - - if No (S) then - return No_List; - end if; - end; - end if; - - -- Add checks to detect proper initialization of scalars that may appear - -- as subprogram parameters. - - if Is_Subprogram (E) - and then Check_Validity_Of_Parameters - then - Apply_Parameter_Validity_Checks (E); - end if; - - -- Deal with delayed aspect specifications. The analysis of the aspect - -- is required to be delayed to the freeze point, thus we analyze the - -- pragma or attribute definition clause in the tree at this point. We - -- also analyze the aspect specification node at the freeze point when - -- the aspect doesn't correspond to pragma/attribute definition clause. - - if Has_Delayed_Aspects (E) then - Analyze_Aspects_At_Freeze_Point (E); - end if; - - -- Here to freeze the entity - - Set_Is_Frozen (E); - - -- Case of entity being frozen is other than a type - - if not Is_Type (E) then - - -- If entity is exported or imported and does not have an external - -- name, now is the time to provide the appropriate default name. - -- Skip this if the entity is stubbed, since we don't need a name - -- for any stubbed routine. For the case on intrinsics, if no - -- external name is specified, then calls will be handled in - -- Exp_Intr.Expand_Intrinsic_Call, and no name is needed. If an - -- external name is provided, then Expand_Intrinsic_Call leaves - -- calls in place for expansion by GIGI. - - if (Is_Imported (E) or else Is_Exported (E)) - and then No (Interface_Name (E)) - and then Convention (E) /= Convention_Stubbed - and then Convention (E) /= Convention_Intrinsic - then - Set_Encoded_Interface_Name - (E, Get_Default_External_Name (E)); - - -- If entity is an atomic object appearing in a declaration and - -- the expression is an aggregate, assign it to a temporary to - -- ensure that the actual assignment is done atomically rather - -- than component-wise (the assignment to the temp may be done - -- component-wise, but that is harmless). - - elsif Is_Atomic (E) - and then Nkind (Parent (E)) = N_Object_Declaration - and then Present (Expression (Parent (E))) - and then Nkind (Expression (Parent (E))) = N_Aggregate - and then Is_Atomic_Aggregate (Expression (Parent (E)), Etype (E)) - then - null; - end if; - - -- For a subprogram, freeze all parameter types and also the return - -- type (RM 13.14(14)). However skip this for internal subprograms. - -- This is also the point where any extra formal parameters are - -- created since we now know whether the subprogram will use a - -- foreign convention. - - if Is_Subprogram (E) then - if not Is_Internal (E) then - declare - F_Type : Entity_Id; - R_Type : Entity_Id; - Warn_Node : Node_Id; - - begin - -- Loop through formals - - Formal := First_Formal (E); - while Present (Formal) loop - F_Type := Etype (Formal); - - -- AI05-0151 : incomplete types can appear in a profile. - -- By the time the entity is frozen, the full view must - -- be available, unless it is a limited view. - - if Is_Incomplete_Type (F_Type) - and then Present (Full_View (F_Type)) - then - F_Type := Full_View (F_Type); - Set_Etype (Formal, F_Type); - end if; - - Freeze_And_Append (F_Type, N, Result); - - if Is_Private_Type (F_Type) - and then Is_Private_Type (Base_Type (F_Type)) - and then No (Full_View (Base_Type (F_Type))) - and then not Is_Generic_Type (F_Type) - and then not Is_Derived_Type (F_Type) - then - -- If the type of a formal is incomplete, subprogram - -- is being frozen prematurely. Within an instance - -- (but not within a wrapper package) this is an - -- artifact of our need to regard the end of an - -- instantiation as a freeze point. Otherwise it is - -- a definite error. - - if In_Instance then - Set_Is_Frozen (E, False); - return No_List; - - elsif not After_Last_Declaration - and then not Freezing_Library_Level_Tagged_Type - then - Error_Msg_Node_1 := F_Type; - Error_Msg - ("type& must be fully defined before this point", - Loc); - end if; - end if; - - -- Check suspicious parameter for C function. These tests - -- apply only to exported/imported subprograms. - - if Warn_On_Export_Import - and then Comes_From_Source (E) - and then (Convention (E) = Convention_C - or else - Convention (E) = Convention_CPP) - and then (Is_Imported (E) or else Is_Exported (E)) - and then Convention (E) /= Convention (Formal) - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (F_Type) - and then not Has_Warnings_Off (Formal) - then - -- Qualify mention of formals with subprogram name - - Error_Msg_Qual_Level := 1; - - -- Check suspicious use of fat C pointer - - if Is_Access_Type (F_Type) - and then Esize (F_Type) > Ttypes.System_Address_Size - then - Error_Msg_N - ("?x?type of & does not correspond to C pointer!", - Formal); - - -- Check suspicious return of boolean - - elsif Root_Type (F_Type) = Standard_Boolean - and then Convention (F_Type) = Convention_Ada - and then not Has_Warnings_Off (F_Type) - and then not Has_Size_Clause (F_Type) - and then VM_Target = No_VM - then - Error_Msg_N - ("& is an 8-bit Ada Boolean?x?", Formal); - Error_Msg_N - ("\use appropriate corresponding type in C " - & "(e.g. char)?x?", Formal); - - -- Check suspicious tagged type - - elsif (Is_Tagged_Type (F_Type) - or else (Is_Access_Type (F_Type) - and then - Is_Tagged_Type - (Designated_Type (F_Type)))) - and then Convention (E) = Convention_C - then - Error_Msg_N - ("?x?& involves a tagged type which does not " - & "correspond to any C type!", Formal); - - -- Check wrong convention subprogram pointer - - elsif Ekind (F_Type) = E_Access_Subprogram_Type - and then not Has_Foreign_Convention (F_Type) - then - Error_Msg_N - ("?x?subprogram pointer & should " - & "have foreign convention!", Formal); - Error_Msg_Sloc := Sloc (F_Type); - Error_Msg_NE - ("\?x?add Convention pragma to declaration of &#", - Formal, F_Type); - end if; - - -- Turn off name qualification after message output - - Error_Msg_Qual_Level := 0; - end if; - - -- Check for unconstrained array in exported foreign - -- convention case. - - if Has_Foreign_Convention (E) - and then not Is_Imported (E) - and then Is_Array_Type (F_Type) - and then not Is_Constrained (F_Type) - and then Warn_On_Export_Import - - -- Exclude VM case, since both .NET and JVM can handle - -- unconstrained arrays without a problem. - - and then VM_Target = No_VM - then - Error_Msg_Qual_Level := 1; - - -- If this is an inherited operation, place the - -- warning on the derived type declaration, rather - -- than on the original subprogram. - - if Nkind (Original_Node (Parent (E))) = - N_Full_Type_Declaration - then - Warn_Node := Parent (E); - - if Formal = First_Formal (E) then - Error_Msg_NE - ("??in inherited operation&", Warn_Node, E); - end if; - else - Warn_Node := Formal; - end if; - - Error_Msg_NE - ("?x?type of argument& is unconstrained array", - Warn_Node, Formal); - Error_Msg_NE - ("?x?foreign caller must pass bounds explicitly", - Warn_Node, Formal); - Error_Msg_Qual_Level := 0; - end if; - - if not From_With_Type (F_Type) then - if Is_Access_Type (F_Type) then - F_Type := Designated_Type (F_Type); - end if; - - -- If the formal is an anonymous_access_to_subprogram - -- freeze the subprogram type as well, to prevent - -- scope anomalies in gigi, because there is no other - -- clear point at which it could be frozen. - - if Is_Itype (Etype (Formal)) - and then Ekind (F_Type) = E_Subprogram_Type - then - Freeze_And_Append (F_Type, N, Result); - end if; - end if; - - Next_Formal (Formal); - end loop; - - -- Case of function: similar checks on return type - - if Ekind (E) = E_Function then - - -- Freeze return type - - R_Type := Etype (E); - - -- AI05-0151: the return type may have been incomplete - -- at the point of declaration. - - if Ekind (R_Type) = E_Incomplete_Type - and then Present (Full_View (R_Type)) - then - R_Type := Full_View (R_Type); - Set_Etype (E, R_Type); - end if; - - Freeze_And_Append (R_Type, N, Result); - - -- Check suspicious return type for C function - - if Warn_On_Export_Import - and then (Convention (E) = Convention_C - or else - Convention (E) = Convention_CPP) - and then (Is_Imported (E) or else Is_Exported (E)) - then - -- Check suspicious return of fat C pointer - - if Is_Access_Type (R_Type) - and then Esize (R_Type) > Ttypes.System_Address_Size - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (R_Type) - then - Error_Msg_N - ("?x?return type of& does not " - & "correspond to C pointer!", E); - - -- Check suspicious return of boolean - - elsif Root_Type (R_Type) = Standard_Boolean - and then Convention (R_Type) = Convention_Ada - and then VM_Target = No_VM - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (R_Type) - and then not Has_Size_Clause (R_Type) - then - declare - N : constant Node_Id := - Result_Definition (Declaration_Node (E)); - begin - Error_Msg_NE - ("return type of & is an 8-bit Ada Boolean?x?", - N, E); - Error_Msg_NE - ("\use appropriate corresponding type in C " - & "(e.g. char)?x?", N, E); - end; - - -- Check suspicious return tagged type - - elsif (Is_Tagged_Type (R_Type) - or else (Is_Access_Type (R_Type) - and then - Is_Tagged_Type - (Designated_Type (R_Type)))) - and then Convention (E) = Convention_C - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (R_Type) - then - Error_Msg_N - ("?x?return type of & does not " - & "correspond to C type!", E); - - -- Check return of wrong convention subprogram pointer - - elsif Ekind (R_Type) = E_Access_Subprogram_Type - and then not Has_Foreign_Convention (R_Type) - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (R_Type) - then - Error_Msg_N - ("?x?& should return a foreign " - & "convention subprogram pointer", E); - Error_Msg_Sloc := Sloc (R_Type); - Error_Msg_NE - ("\?x?add Convention pragma to declaration of& #", - E, R_Type); - end if; - end if; - - -- Give warning for suspicious return of a result of an - -- unconstrained array type in a foreign convention - -- function. - - if Has_Foreign_Convention (E) - - -- We are looking for a return of unconstrained array - - and then Is_Array_Type (R_Type) - and then not Is_Constrained (R_Type) - - -- Exclude imported routines, the warning does not - -- belong on the import, but rather on the routine - -- definition. - - and then not Is_Imported (E) - - -- Exclude VM case, since both .NET and JVM can handle - -- return of unconstrained arrays without a problem. - - and then VM_Target = No_VM - - -- Check that general warning is enabled, and that it - -- is not suppressed for this particular case. - - and then Warn_On_Export_Import - and then not Has_Warnings_Off (E) - and then not Has_Warnings_Off (R_Type) - then - Error_Msg_N - ("?x?foreign convention function& should not " & - "return unconstrained array!", E); - end if; - end if; - end; - - -- Pre/post conditions are implemented through a subprogram in - -- the corresponding body, and therefore are not checked on an - -- imported subprogram for which the body is not available. - - -- Could consider generating a wrapper to take care of this??? - - if Is_Subprogram (E) - and then Is_Imported (E) - and then Present (Contract (E)) - and then Present (Spec_PPC_List (Contract (E))) - then - Error_Msg_NE - ("pre/post conditions on imported subprogram " - & "are not enforced??", E, Spec_PPC_List (Contract (E))); - end if; - - end if; - - -- Must freeze its parent first if it is a derived subprogram - - if Present (Alias (E)) then - Freeze_And_Append (Alias (E), N, Result); - end if; - - -- We don't freeze internal subprograms, because we don't normally - -- want addition of extra formals or mechanism setting to happen - -- for those. However we do pass through predefined dispatching - -- cases, since extra formals may be needed in some cases, such as - -- for the stream 'Input function (build-in-place formals). - - if not Is_Internal (E) - or else Is_Predefined_Dispatching_Operation (E) - then - Freeze_Subprogram (E); - end if; - - -- Here for other than a subprogram or type - - else - -- If entity has a type, and it is not a generic unit, then - -- freeze it first (RM 13.14(10)). - - if Present (Etype (E)) - and then Ekind (E) /= E_Generic_Function - then - Freeze_And_Append (Etype (E), N, Result); - end if; - - -- Special processing for objects created by object declaration - - if Nkind (Declaration_Node (E)) = N_Object_Declaration then - - -- Abstract type allowed only for C++ imported variables or - -- constants. - - -- Note: we inhibit this check for objects that do not come - -- from source because there is at least one case (the - -- expansion of x'Class'Input where x is abstract) where we - -- legitimately generate an abstract object. - - if Is_Abstract_Type (Etype (E)) - and then Comes_From_Source (Parent (E)) - and then not (Is_Imported (E) - and then Is_CPP_Class (Etype (E))) - then - Error_Msg_N ("type of object cannot be abstract", - Object_Definition (Parent (E))); - - if Is_CPP_Class (Etype (E)) then - Error_Msg_NE - ("\} may need a cpp_constructor", - Object_Definition (Parent (E)), Etype (E)); - end if; - end if; - - -- For object created by object declaration, perform required - -- categorization (preelaborate and pure) checks. Defer these - -- checks to freeze time since pragma Import inhibits default - -- initialization and thus pragma Import affects these checks. - - Validate_Object_Declaration (Declaration_Node (E)); - - -- If there is an address clause, check that it is valid - - Check_Address_Clause (E); - - -- If the object needs any kind of default initialization, an - -- error must be issued if No_Default_Initialization applies. - -- The check doesn't apply to imported objects, which are not - -- ever default initialized, and is why the check is deferred - -- until freezing, at which point we know if Import applies. - -- Deferred constants are also exempted from this test because - -- their completion is explicit, or through an import pragma. - - if Ekind (E) = E_Constant - and then Present (Full_View (E)) - then - null; - - elsif Comes_From_Source (E) - and then not Is_Imported (E) - and then not Has_Init_Expression (Declaration_Node (E)) - and then - ((Has_Non_Null_Base_Init_Proc (Etype (E)) - and then not No_Initialization (Declaration_Node (E)) - and then not Is_Value_Type (Etype (E)) - and then not Initialization_Suppressed (Etype (E))) - or else - (Needs_Simple_Initialization (Etype (E)) - and then not Is_Internal (E))) - then - Has_Default_Initialization := True; - Check_Restriction - (No_Default_Initialization, Declaration_Node (E)); - end if; - - -- Check that a Thread_Local_Storage variable does not have - -- default initialization, and any explicit initialization must - -- either be the null constant or a static constant. - - if Has_Pragma_Thread_Local_Storage (E) then - declare - Decl : constant Node_Id := Declaration_Node (E); - begin - if Has_Default_Initialization - or else - (Has_Init_Expression (Decl) - and then - (No (Expression (Decl)) - or else not - (Is_Static_Expression (Expression (Decl)) - or else - Nkind (Expression (Decl)) = N_Null))) - then - Error_Msg_NE - ("Thread_Local_Storage variable& is " - & "improperly initialized", Decl, E); - Error_Msg_NE - ("\only allowed initialization is explicit " - & "NULL or static expression", Decl, E); - end if; - end; - end if; - - -- For imported objects, set Is_Public unless there is also an - -- address clause, which means that there is no external symbol - -- needed for the Import (Is_Public may still be set for other - -- unrelated reasons). Note that we delayed this processing - -- till freeze time so that we can be sure not to set the flag - -- if there is an address clause. If there is such a clause, - -- then the only purpose of the Import pragma is to suppress - -- implicit initialization. - - if Is_Imported (E) - and then No (Address_Clause (E)) - then - Set_Is_Public (E); - end if; - - -- For convention C objects of an enumeration type, warn if - -- the size is not integer size and no explicit size given. - -- Skip warning for Boolean, and Character, assume programmer - -- expects 8-bit sizes for these cases. - - if (Convention (E) = Convention_C - or else - Convention (E) = Convention_CPP) - and then Is_Enumeration_Type (Etype (E)) - and then not Is_Character_Type (Etype (E)) - and then not Is_Boolean_Type (Etype (E)) - and then Esize (Etype (E)) < Standard_Integer_Size - and then not Has_Size_Clause (E) - then - Error_Msg_Uint_1 := UI_From_Int (Standard_Integer_Size); - Error_Msg_N - ("??convention C enumeration object has size less than ^", - E); - Error_Msg_N ("\?use explicit size clause to set size", E); - end if; - end if; - - -- Check that a constant which has a pragma Volatile[_Components] - -- or Atomic[_Components] also has a pragma Import (RM C.6(13)). - - -- Note: Atomic[_Components] also sets Volatile[_Components] - - if Ekind (E) = E_Constant - and then (Has_Volatile_Components (E) or else Is_Volatile (E)) - and then not Is_Imported (E) - then - -- Make sure we actually have a pragma, and have not merely - -- inherited the indication from elsewhere (e.g. an address - -- clause, which is not good enough in RM terms!) - - if Has_Rep_Pragma (E, Name_Atomic) - or else - Has_Rep_Pragma (E, Name_Atomic_Components) - then - Error_Msg_N - ("stand alone atomic constant must be " & - "imported (RM C.6(13))", E); - - elsif Has_Rep_Pragma (E, Name_Volatile) - or else - Has_Rep_Pragma (E, Name_Volatile_Components) - then - Error_Msg_N - ("stand alone volatile constant must be " & - "imported (RM C.6(13))", E); - end if; - end if; - - -- Static objects require special handling - - if (Ekind (E) = E_Constant or else Ekind (E) = E_Variable) - and then Is_Statically_Allocated (E) - then - Freeze_Static_Object (E); - end if; - - -- Remaining step is to layout objects - - if Ekind (E) = E_Variable - or else - Ekind (E) = E_Constant - or else - Ekind (E) = E_Loop_Parameter - or else - Is_Formal (E) - then - Layout_Object (E); - end if; - - -- If initialization statements were captured in an expression - -- with actions with null expression, and the object does not - -- have delayed freezing, move them back now directly within the - -- enclosing statement sequence. - - if Ekind_In (E, E_Constant, E_Variable) - and then not Has_Delayed_Freeze (E) - then - declare - Init_Stmts : constant Node_Id := - Initialization_Statements (E); - begin - if Present (Init_Stmts) - and then Nkind (Init_Stmts) = N_Expression_With_Actions - and then Nkind (Expression (Init_Stmts)) = N_Null_Statement - then - Insert_List_Before (Init_Stmts, Actions (Init_Stmts)); - Remove (Init_Stmts); - Set_Initialization_Statements (E, Empty); - end if; - end; - end if; - - end if; - - -- Case of a type or subtype being frozen - - else - -- We used to check here that a full type must have preelaborable - -- initialization if it completes a private type specified with - -- pragma Preelaborable_Initialization, but that missed cases where - -- the types occur within a generic package, since the freezing - -- that occurs within a containing scope generally skips traversal - -- of a generic unit's declarations (those will be frozen within - -- instances). This check was moved to Analyze_Package_Specification. - - -- The type may be defined in a generic unit. This can occur when - -- freezing a generic function that returns the type (which is - -- defined in a parent unit). It is clearly meaningless to freeze - -- this type. However, if it is a subtype, its size may be determi- - -- nable and used in subsequent checks, so might as well try to - -- compute it. - - -- In Ada 2012, Freeze_Entities is also used in the front end to - -- trigger the analysis of aspect expressions, so in this case we - -- want to continue the freezing process. - - if Present (Scope (E)) - and then Is_Generic_Unit (Scope (E)) - and then not Has_Predicates (E) - then - Check_Compile_Time_Size (E); - return No_List; - end if; - - -- Deal with special cases of freezing for subtype - - if E /= Base_Type (E) then - - -- Before we do anything else, a specialized test for the case of - -- a size given for an array where the array needs to be packed, - -- but was not so the size cannot be honored. This would of course - -- be caught by the backend, and indeed we don't catch all cases. - -- The point is that we can give a better error message in those - -- cases that we do catch with the circuitry here. Also if pragma - -- Implicit_Packing is set, this is where the packing occurs. - - -- The reason we do this so early is that the processing in the - -- automatic packing case affects the layout of the base type, so - -- it must be done before we freeze the base type. - - if Is_Array_Type (E) then - declare - Lo, Hi : Node_Id; - Ctyp : constant Entity_Id := Component_Type (E); - - begin - -- Check enabling conditions. These are straightforward - -- except for the test for a limited composite type. This - -- eliminates the rare case of a array of limited components - -- where there are issues of whether or not we can go ahead - -- and pack the array (since we can't freely pack and unpack - -- arrays if they are limited). - - -- Note that we check the root type explicitly because the - -- whole point is we are doing this test before we have had - -- a chance to freeze the base type (and it is that freeze - -- action that causes stuff to be inherited). - - if Present (Size_Clause (E)) - and then Known_Static_RM_Size (E) - and then not Is_Packed (E) - and then not Has_Pragma_Pack (E) - and then Number_Dimensions (E) = 1 - and then not Has_Component_Size_Clause (E) - and then Known_Static_RM_Size (Ctyp) - and then not Is_Limited_Composite (E) - and then not Is_Packed (Root_Type (E)) - and then not Has_Component_Size_Clause (Root_Type (E)) - and then not (CodePeer_Mode or Alfa_Mode) - then - Get_Index_Bounds (First_Index (E), Lo, Hi); - - if Compile_Time_Known_Value (Lo) - and then Compile_Time_Known_Value (Hi) - and then Known_Static_RM_Size (Ctyp) - and then RM_Size (Ctyp) < 64 - then - declare - Lov : constant Uint := Expr_Value (Lo); - Hiv : constant Uint := Expr_Value (Hi); - Len : constant Uint := UI_Max - (Uint_0, - Hiv - Lov + 1); - Rsiz : constant Uint := RM_Size (Ctyp); - SZ : constant Node_Id := Size_Clause (E); - Btyp : constant Entity_Id := Base_Type (E); - - -- What we are looking for here is the situation where - -- the RM_Size given would be exactly right if there - -- was a pragma Pack (resulting in the component size - -- being the same as the RM_Size). Furthermore, the - -- component type size must be an odd size (not a - -- multiple of storage unit). If the component RM size - -- is an exact number of storage units that is a power - -- of two, the array is not packed and has a standard - -- representation. - - begin - if RM_Size (E) = Len * Rsiz - and then Rsiz mod System_Storage_Unit /= 0 - then - -- For implicit packing mode, just set the - -- component size silently. - - if Implicit_Packing then - Set_Component_Size (Btyp, Rsiz); - Set_Is_Bit_Packed_Array (Btyp); - Set_Is_Packed (Btyp); - Set_Has_Non_Standard_Rep (Btyp); - - -- Otherwise give an error message - - else - Error_Msg_NE - ("size given for& too small", SZ, E); - Error_Msg_N -- CODEFIX - ("\use explicit pragma Pack " - & "or use pragma Implicit_Packing", SZ); - end if; - - elsif RM_Size (E) = Len * Rsiz - and then Implicit_Packing - and then - (Rsiz / System_Storage_Unit = 1 - or else Rsiz / System_Storage_Unit = 2 - or else Rsiz / System_Storage_Unit = 4) - then - - -- Not a packed array, but indicate the desired - -- component size, for the back-end. - - Set_Component_Size (Btyp, Rsiz); - end if; - end; - end if; - end if; - end; - end if; - - -- If ancestor subtype present, freeze that first. Note that this - -- will also get the base type frozen. Need RM reference ??? - - Atype := Ancestor_Subtype (E); - - if Present (Atype) then - Freeze_And_Append (Atype, N, Result); - - -- No ancestor subtype present - - else - -- See if we have a nearest ancestor that has a predicate. - -- That catches the case of derived type with a predicate. - -- Need RM reference here ??? - - Atype := Nearest_Ancestor (E); - - if Present (Atype) and then Has_Predicates (Atype) then - Freeze_And_Append (Atype, N, Result); - end if; - - -- Freeze base type before freezing the entity (RM 13.14(15)) - - if E /= Base_Type (E) then - Freeze_And_Append (Base_Type (E), N, Result); - end if; - end if; - - -- A subtype inherits all the type-related representation aspects - -- from its parents (RM 13.1(8)). - - Inherit_Aspects_At_Freeze_Point (E); - - -- For a derived type, freeze its parent type first (RM 13.14(15)) - - elsif Is_Derived_Type (E) then - Freeze_And_Append (Etype (E), N, Result); - Freeze_And_Append (First_Subtype (Etype (E)), N, Result); - - -- A derived type inherits each type-related representation aspect - -- of its parent type that was directly specified before the - -- declaration of the derived type (RM 13.1(15)). - - Inherit_Aspects_At_Freeze_Point (E); - end if; - - -- For array type, freeze index types and component type first - -- before freezing the array (RM 13.14(15)). - - if Is_Array_Type (E) then - declare - FS : constant Entity_Id := First_Subtype (E); - Ctyp : constant Entity_Id := Component_Type (E); - Clause : Entity_Id; - - Non_Standard_Enum : Boolean := False; - -- Set true if any of the index types is an enumeration type - -- with a non-standard representation. - - begin - Freeze_And_Append (Ctyp, N, Result); - - Indx := First_Index (E); - while Present (Indx) loop - Freeze_And_Append (Etype (Indx), N, Result); - - if Is_Enumeration_Type (Etype (Indx)) - and then Has_Non_Standard_Rep (Etype (Indx)) - then - Non_Standard_Enum := True; - end if; - - Next_Index (Indx); - end loop; - - -- Processing that is done only for base types - - if Ekind (E) = E_Array_Type then - - -- Propagate flags for component type - - if Is_Controlled (Component_Type (E)) - or else Has_Controlled_Component (Ctyp) - then - Set_Has_Controlled_Component (E); - end if; - - if Has_Unchecked_Union (Component_Type (E)) then - Set_Has_Unchecked_Union (E); - end if; - - -- If packing was requested or if the component size was set - -- explicitly, then see if bit packing is required. This - -- processing is only done for base types, since all the - -- representation aspects involved are type-related. This - -- is not just an optimization, if we start processing the - -- subtypes, they interfere with the settings on the base - -- type (this is because Is_Packed has a slightly different - -- meaning before and after freezing). - - declare - Csiz : Uint; - Esiz : Uint; - - begin - if (Is_Packed (E) or else Has_Pragma_Pack (E)) - and then Known_Static_RM_Size (Ctyp) - and then not Has_Component_Size_Clause (E) - then - Csiz := UI_Max (RM_Size (Ctyp), 1); - - elsif Known_Component_Size (E) then - Csiz := Component_Size (E); - - elsif not Known_Static_Esize (Ctyp) then - Csiz := Uint_0; - - else - Esiz := Esize (Ctyp); - - -- We can set the component size if it is less than - -- 16, rounding it up to the next storage unit size. - - if Esiz <= 8 then - Csiz := Uint_8; - elsif Esiz <= 16 then - Csiz := Uint_16; - else - Csiz := Uint_0; - end if; - - -- Set component size up to match alignment if it - -- would otherwise be less than the alignment. This - -- deals with cases of types whose alignment exceeds - -- their size (padded types). - - if Csiz /= 0 then - declare - A : constant Uint := Alignment_In_Bits (Ctyp); - begin - if Csiz < A then - Csiz := A; - end if; - end; - end if; - end if; - - -- Case of component size that may result in packing - - if 1 <= Csiz and then Csiz <= 64 then - declare - Ent : constant Entity_Id := - First_Subtype (E); - Pack_Pragma : constant Node_Id := - Get_Rep_Pragma (Ent, Name_Pack); - Comp_Size_C : constant Node_Id := - Get_Attribute_Definition_Clause - (Ent, Attribute_Component_Size); - begin - -- Warn if we have pack and component size so that - -- the pack is ignored. - - -- Note: here we must check for the presence of a - -- component size before checking for a Pack pragma - -- to deal with the case where the array type is a - -- derived type whose parent is currently private. - - if Present (Comp_Size_C) - and then Has_Pragma_Pack (Ent) - and then Warn_On_Redundant_Constructs - then - Error_Msg_Sloc := Sloc (Comp_Size_C); - Error_Msg_NE - ("?r?pragma Pack for& ignored!", - Pack_Pragma, Ent); - Error_Msg_N - ("\?r?explicit component size given#!", - Pack_Pragma); - Set_Is_Packed (Base_Type (Ent), False); - Set_Is_Bit_Packed_Array (Base_Type (Ent), False); - end if; - - -- Set component size if not already set by a - -- component size clause. - - if not Present (Comp_Size_C) then - Set_Component_Size (E, Csiz); - end if; - - -- Check for base type of 8, 16, 32 bits, where an - -- unsigned subtype has a length one less than the - -- base type (e.g. Natural subtype of Integer). - - -- In such cases, if a component size was not set - -- explicitly, then generate a warning. - - if Has_Pragma_Pack (E) - and then not Present (Comp_Size_C) - and then - (Csiz = 7 or else Csiz = 15 or else Csiz = 31) - and then Esize (Base_Type (Ctyp)) = Csiz + 1 - then - Error_Msg_Uint_1 := Csiz; - - if Present (Pack_Pragma) then - Error_Msg_N - ("??pragma Pack causes component size " - & "to be ^!", Pack_Pragma); - Error_Msg_N - ("\??use Component_Size to set " - & "desired value!", Pack_Pragma); - end if; - end if; - - -- Actual packing is not needed for 8, 16, 32, 64. - -- Also not needed for 24 if alignment is 1. - - if Csiz = 8 - or else Csiz = 16 - or else Csiz = 32 - or else Csiz = 64 - or else (Csiz = 24 and then Alignment (Ctyp) = 1) - then - -- Here the array was requested to be packed, - -- but the packing request had no effect, so - -- Is_Packed is reset. - - -- Note: semantically this means that we lose - -- track of the fact that a derived type - -- inherited a pragma Pack that was non- - -- effective, but that seems fine. - - -- We regard a Pack pragma as a request to set - -- a representation characteristic, and this - -- request may be ignored. - - Set_Is_Packed (Base_Type (E), False); - Set_Is_Bit_Packed_Array (Base_Type (E), False); - - if Known_Static_Esize (Component_Type (E)) - and then Esize (Component_Type (E)) = Csiz - then - Set_Has_Non_Standard_Rep - (Base_Type (E), False); - end if; - - -- In all other cases, packing is indeed needed - - else - Set_Has_Non_Standard_Rep (Base_Type (E), True); - Set_Is_Bit_Packed_Array (Base_Type (E), True); - Set_Is_Packed (Base_Type (E), True); - end if; - end; - end if; - end; - - -- Check for Atomic_Components or Aliased with unsuitable - -- packing or explicit component size clause given. - - if (Has_Atomic_Components (E) - or else Has_Aliased_Components (E)) - and then (Has_Component_Size_Clause (E) - or else Is_Packed (E)) - then - Alias_Atomic_Check : declare - - procedure Complain_CS (T : String); - -- Outputs error messages for incorrect CS clause or - -- pragma Pack for aliased or atomic components (T is - -- "aliased" or "atomic"); - - ----------------- - -- Complain_CS -- - ----------------- - - procedure Complain_CS (T : String) is - begin - if Has_Component_Size_Clause (E) then - Clause := - Get_Attribute_Definition_Clause - (FS, Attribute_Component_Size); - - if Known_Static_Esize (Ctyp) then - Error_Msg_N - ("incorrect component size for " - & T & " components", Clause); - Error_Msg_Uint_1 := Esize (Ctyp); - Error_Msg_N - ("\only allowed value is^", Clause); - - else - Error_Msg_N - ("component size cannot be given for " - & T & " components", Clause); - end if; - - else - Error_Msg_N - ("cannot pack " & T & " components", - Get_Rep_Pragma (FS, Name_Pack)); - end if; - - return; - end Complain_CS; - - -- Start of processing for Alias_Atomic_Check - - begin - - -- If object size of component type isn't known, we - -- cannot be sure so we defer to the back end. - - if not Known_Static_Esize (Ctyp) then - null; - - -- Case where component size has no effect. First - -- check for object size of component type multiple - -- of the storage unit size. - - elsif Esize (Ctyp) mod System_Storage_Unit = 0 - - -- OK in both packing case and component size case - -- if RM size is known and static and the same as - -- the object size. - - and then - ((Known_Static_RM_Size (Ctyp) - and then Esize (Ctyp) = RM_Size (Ctyp)) - - -- Or if we have an explicit component size - -- clause and the component size and object size - -- are equal. - - or else - (Has_Component_Size_Clause (E) - and then Component_Size (E) = Esize (Ctyp))) - then - null; - - elsif Has_Aliased_Components (E) - or else Is_Aliased (Ctyp) - then - Complain_CS ("aliased"); - - elsif Has_Atomic_Components (E) - or else Is_Atomic (Ctyp) - then - Complain_CS ("atomic"); - end if; - end Alias_Atomic_Check; - end if; - - -- Warn for case of atomic type - - Clause := Get_Rep_Pragma (FS, Name_Atomic); - - if Present (Clause) - and then not Addressable (Component_Size (FS)) - then - Error_Msg_NE - ("non-atomic components of type& may not be " - & "accessible by separate tasks??", Clause, E); - - if Has_Component_Size_Clause (E) then - Error_Msg_Sloc := - Sloc - (Get_Attribute_Definition_Clause - (FS, Attribute_Component_Size)); - Error_Msg_N - ("\because of component size clause#??", - Clause); - - elsif Has_Pragma_Pack (E) then - Error_Msg_Sloc := - Sloc (Get_Rep_Pragma (FS, Name_Pack)); - Error_Msg_N - ("\because of pragma Pack#??", Clause); - end if; - end if; - - -- Check for scalar storage order - - if Present (Get_Attribute_Definition_Clause - (E, Attribute_Scalar_Storage_Order)) - then - Check_Component_Storage_Order (E, Empty); - end if; - - -- Processing that is done only for subtypes - - else - -- Acquire alignment from base type - - if Unknown_Alignment (E) then - Set_Alignment (E, Alignment (Base_Type (E))); - Adjust_Esize_Alignment (E); - end if; - end if; - - -- For bit-packed arrays, check the size - - if Is_Bit_Packed_Array (E) and then Known_RM_Size (E) then - declare - SizC : constant Node_Id := Size_Clause (E); - - Discard : Boolean; - pragma Warnings (Off, Discard); - - begin - -- It is not clear if it is possible to have no size - -- clause at this stage, but it is not worth worrying - -- about. Post error on the entity name in the size - -- clause if present, else on the type entity itself. - - if Present (SizC) then - Check_Size (Name (SizC), E, RM_Size (E), Discard); - else - Check_Size (E, E, RM_Size (E), Discard); - end if; - end; - end if; - - -- If any of the index types was an enumeration type with a - -- non-standard rep clause, then we indicate that the array - -- type is always packed (even if it is not bit packed). - - if Non_Standard_Enum then - Set_Has_Non_Standard_Rep (Base_Type (E)); - Set_Is_Packed (Base_Type (E)); - end if; - - Set_Component_Alignment_If_Not_Set (E); - - -- If the array is packed, we must create the packed array - -- type to be used to actually implement the type. This is - -- only needed for real array types (not for string literal - -- types, since they are present only for the front end). - - if Is_Packed (E) - and then Ekind (E) /= E_String_Literal_Subtype - then - Create_Packed_Array_Type (E); - Freeze_And_Append (Packed_Array_Type (E), N, Result); - - -- Size information of packed array type is copied to the - -- array type, since this is really the representation. But - -- do not override explicit existing size values. If the - -- ancestor subtype is constrained the packed_array_type - -- will be inherited from it, but the size may have been - -- provided already, and must not be overridden either. - - if not Has_Size_Clause (E) - and then - (No (Ancestor_Subtype (E)) - or else not Has_Size_Clause (Ancestor_Subtype (E))) - then - Set_Esize (E, Esize (Packed_Array_Type (E))); - Set_RM_Size (E, RM_Size (Packed_Array_Type (E))); - end if; - - if not Has_Alignment_Clause (E) then - Set_Alignment (E, Alignment (Packed_Array_Type (E))); - end if; - end if; - - -- For non-packed arrays set the alignment of the array to the - -- alignment of the component type if it is unknown. Skip this - -- in atomic case (atomic arrays may need larger alignments). - - if not Is_Packed (E) - and then Unknown_Alignment (E) - and then Known_Alignment (Ctyp) - and then Known_Static_Component_Size (E) - and then Known_Static_Esize (Ctyp) - and then Esize (Ctyp) = Component_Size (E) - and then not Is_Atomic (E) - then - Set_Alignment (E, Alignment (Component_Type (E))); - end if; - end; - - -- For a class-wide type, the corresponding specific type is - -- frozen as well (RM 13.14(15)) - - elsif Is_Class_Wide_Type (E) then - Freeze_And_Append (Root_Type (E), N, Result); - - -- If the base type of the class-wide type is still incomplete, - -- the class-wide remains unfrozen as well. This is legal when - -- E is the formal of a primitive operation of some other type - -- which is being frozen. - - if not Is_Frozen (Root_Type (E)) then - Set_Is_Frozen (E, False); - return Result; - end if; - - -- The equivalent type associated with a class-wide subtype needs - -- to be frozen to ensure that its layout is done. - - if Ekind (E) = E_Class_Wide_Subtype - and then Present (Equivalent_Type (E)) - then - Freeze_And_Append (Equivalent_Type (E), N, Result); - end if; - - -- Generate an itype reference for a library-level class-wide type - -- at the freeze point. Otherwise the first explicit reference to - -- the type may appear in an inner scope which will be rejected by - -- the back-end. - - if Is_Itype (E) - and then Is_Compilation_Unit (Scope (E)) - then - declare - Ref : constant Node_Id := Make_Itype_Reference (Loc); - - begin - Set_Itype (Ref, E); - - -- From a gigi point of view, a class-wide subtype derives - -- from its record equivalent type. As a result, the itype - -- reference must appear after the freeze node of the - -- equivalent type or gigi will reject the reference. - - if Ekind (E) = E_Class_Wide_Subtype - and then Present (Equivalent_Type (E)) - then - Insert_After (Freeze_Node (Equivalent_Type (E)), Ref); - else - Add_To_Result (Ref); - end if; - end; - end if; - - -- For a record type or record subtype, freeze all component types - -- (RM 13.14(15)). We test for E_Record_(sub)Type here, rather than - -- using Is_Record_Type, because we don't want to attempt the freeze - -- for the case of a private type with record extension (we will do - -- that later when the full type is frozen). - - elsif Ekind_In (E, E_Record_Type, E_Record_Subtype) then - Freeze_Record_Type (E); - - -- For a concurrent type, freeze corresponding record type. This - -- does not correspond to any specific rule in the RM, but the - -- record type is essentially part of the concurrent type. - -- Freeze as well all local entities. This includes record types - -- created for entry parameter blocks, and whatever local entities - -- may appear in the private part. - - elsif Is_Concurrent_Type (E) then - if Present (Corresponding_Record_Type (E)) then - Freeze_And_Append - (Corresponding_Record_Type (E), N, Result); - end if; - - Comp := First_Entity (E); - while Present (Comp) loop - if Is_Type (Comp) then - Freeze_And_Append (Comp, N, Result); - - elsif (Ekind (Comp)) /= E_Function then - if Is_Itype (Etype (Comp)) - and then Underlying_Type (Scope (Etype (Comp))) = E - then - Undelay_Type (Etype (Comp)); - end if; - - Freeze_And_Append (Etype (Comp), N, Result); - end if; - - Next_Entity (Comp); - end loop; - - -- Private types are required to point to the same freeze node as - -- their corresponding full views. The freeze node itself has to - -- point to the partial view of the entity (because from the partial - -- view, we can retrieve the full view, but not the reverse). - -- However, in order to freeze correctly, we need to freeze the full - -- view. If we are freezing at the end of a scope (or within the - -- scope of the private type), the partial and full views will have - -- been swapped, the full view appears first in the entity chain and - -- the swapping mechanism ensures that the pointers are properly set - -- (on scope exit). - - -- If we encounter the partial view before the full view (e.g. when - -- freezing from another scope), we freeze the full view, and then - -- set the pointers appropriately since we cannot rely on swapping to - -- fix things up (subtypes in an outer scope might not get swapped). - - elsif Is_Incomplete_Or_Private_Type (E) - and then not Is_Generic_Type (E) - then - -- The construction of the dispatch table associated with library - -- level tagged types forces freezing of all the primitives of the - -- type, which may cause premature freezing of the partial view. - -- For example: - - -- package Pkg is - -- type T is tagged private; - -- type DT is new T with private; - -- procedure Prim (X : in out T; Y : in out DT'Class); - -- private - -- type T is tagged null record; - -- Obj : T; - -- type DT is new T with null record; - -- end; - - -- In this case the type will be frozen later by the usual - -- mechanism: an object declaration, an instantiation, or the - -- end of a declarative part. - - if Is_Library_Level_Tagged_Type (E) - and then not Present (Full_View (E)) - then - Set_Is_Frozen (E, False); - return Result; - - -- Case of full view present - - elsif Present (Full_View (E)) then - - -- If full view has already been frozen, then no further - -- processing is required - - if Is_Frozen (Full_View (E)) then - Set_Has_Delayed_Freeze (E, False); - Set_Freeze_Node (E, Empty); - Check_Debug_Info_Needed (E); - - -- Otherwise freeze full view and patch the pointers so that - -- the freeze node will elaborate both views in the back-end. - - else - declare - Full : constant Entity_Id := Full_View (E); - - begin - if Is_Private_Type (Full) - and then Present (Underlying_Full_View (Full)) - then - Freeze_And_Append - (Underlying_Full_View (Full), N, Result); - end if; - - Freeze_And_Append (Full, N, Result); - - if Has_Delayed_Freeze (E) then - F_Node := Freeze_Node (Full); - - if Present (F_Node) then - Set_Freeze_Node (E, F_Node); - Set_Entity (F_Node, E); - - else - -- {Incomplete,Private}_Subtypes with Full_Views - -- constrained by discriminants. - - Set_Has_Delayed_Freeze (E, False); - Set_Freeze_Node (E, Empty); - end if; - end if; - end; - - Check_Debug_Info_Needed (E); - end if; - - -- AI-117 requires that the convention of a partial view be the - -- same as the convention of the full view. Note that this is a - -- recognized breach of privacy, but it's essential for logical - -- consistency of representation, and the lack of a rule in - -- RM95 was an oversight. - - Set_Convention (E, Convention (Full_View (E))); - - Set_Size_Known_At_Compile_Time (E, - Size_Known_At_Compile_Time (Full_View (E))); - - -- Size information is copied from the full view to the - -- incomplete or private view for consistency. - - -- We skip this is the full view is not a type. This is very - -- strange of course, and can only happen as a result of - -- certain illegalities, such as a premature attempt to derive - -- from an incomplete type. - - if Is_Type (Full_View (E)) then - Set_Size_Info (E, Full_View (E)); - Set_RM_Size (E, RM_Size (Full_View (E))); - end if; - - return Result; - - -- Case of no full view present. If entity is derived or subtype, - -- it is safe to freeze, correctness depends on the frozen status - -- of parent. Otherwise it is either premature usage, or a Taft - -- amendment type, so diagnosis is at the point of use and the - -- type might be frozen later. - - elsif E /= Base_Type (E) - or else Is_Derived_Type (E) - then - null; - - else - Set_Is_Frozen (E, False); - return No_List; - end if; - - -- For access subprogram, freeze types of all formals, the return - -- type was already frozen, since it is the Etype of the function. - -- Formal types can be tagged Taft amendment types, but otherwise - -- they cannot be incomplete. - - elsif Ekind (E) = E_Subprogram_Type then - Formal := First_Formal (E); - while Present (Formal) loop - if Ekind (Etype (Formal)) = E_Incomplete_Type - and then No (Full_View (Etype (Formal))) - and then not Is_Value_Type (Etype (Formal)) - then - if Is_Tagged_Type (Etype (Formal)) then - null; - - -- AI05-151: Incomplete types are allowed in access to - -- subprogram specifications. - - elsif Ada_Version < Ada_2012 then - Error_Msg_NE - ("invalid use of incomplete type&", E, Etype (Formal)); - end if; - end if; - - Freeze_And_Append (Etype (Formal), N, Result); - Next_Formal (Formal); - end loop; - - Freeze_Subprogram (E); - - -- For access to a protected subprogram, freeze the equivalent type - -- (however this is not set if we are not generating code or if this - -- is an anonymous type used just for resolution). - - elsif Is_Access_Protected_Subprogram_Type (E) then - if Present (Equivalent_Type (E)) then - Freeze_And_Append (Equivalent_Type (E), N, Result); - end if; - end if; - - -- Generic types are never seen by the back-end, and are also not - -- processed by the expander (since the expander is turned off for - -- generic processing), so we never need freeze nodes for them. - - if Is_Generic_Type (E) then - return Result; - end if; - - -- Some special processing for non-generic types to complete - -- representation details not known till the freeze point. - - if Is_Fixed_Point_Type (E) then - Freeze_Fixed_Point_Type (E); - - -- Some error checks required for ordinary fixed-point type. Defer - -- these till the freeze-point since we need the small and range - -- values. We only do these checks for base types - - if Is_Ordinary_Fixed_Point_Type (E) and then Is_Base_Type (E) then - if Small_Value (E) < Ureal_2_M_80 then - Error_Msg_Name_1 := Name_Small; - Error_Msg_N - ("`&''%` too small, minimum allowed is 2.0'*'*(-80)", E); - - elsif Small_Value (E) > Ureal_2_80 then - Error_Msg_Name_1 := Name_Small; - Error_Msg_N - ("`&''%` too large, maximum allowed is 2.0'*'*80", E); - end if; - - if Expr_Value_R (Type_Low_Bound (E)) < Ureal_M_10_36 then - Error_Msg_Name_1 := Name_First; - Error_Msg_N - ("`&''%` too small, minimum allowed is -10.0'*'*36", E); - end if; - - if Expr_Value_R (Type_High_Bound (E)) > Ureal_10_36 then - Error_Msg_Name_1 := Name_Last; - Error_Msg_N - ("`&''%` too large, maximum allowed is 10.0'*'*36", E); - end if; - end if; - - elsif Is_Enumeration_Type (E) then - Freeze_Enumeration_Type (E); - - elsif Is_Integer_Type (E) then - Adjust_Esize_For_Alignment (E); - - if Is_Modular_Integer_Type (E) - and then Warn_On_Suspicious_Modulus_Value - then - Check_Suspicious_Modulus (E); - end if; - - elsif Is_Access_Type (E) - and then not Is_Access_Subprogram_Type (E) - then - -- If a pragma Default_Storage_Pool applies, and this type has no - -- Storage_Pool or Storage_Size clause (which must have occurred - -- before the freezing point), then use the default. This applies - -- only to base types. - - -- None of this applies to access to subprograms, for which there - -- are clearly no pools. - - if Present (Default_Pool) - and then Is_Base_Type (E) - and then not Has_Storage_Size_Clause (E) - and then No (Associated_Storage_Pool (E)) - then - -- Case of pragma Default_Storage_Pool (null) - - if Nkind (Default_Pool) = N_Null then - Set_No_Pool_Assigned (E); - - -- Case of pragma Default_Storage_Pool (storage_pool_NAME) - - else - Set_Associated_Storage_Pool (E, Entity (Default_Pool)); - end if; - end if; - - -- Check restriction for standard storage pool - - if No (Associated_Storage_Pool (E)) then - Check_Restriction (No_Standard_Storage_Pools, E); - end if; - - -- Deal with error message for pure access type. This is not an - -- error in Ada 2005 if there is no pool (see AI-366). - - if Is_Pure_Unit_Access_Type (E) - and then (Ada_Version < Ada_2005 - or else not No_Pool_Assigned (E)) - then - Error_Msg_N ("named access type not allowed in pure unit", E); - - if Ada_Version >= Ada_2005 then - Error_Msg_N - ("\would be legal if Storage_Size of 0 given??", E); - - elsif No_Pool_Assigned (E) then - Error_Msg_N - ("\would be legal in Ada 2005??", E); - - else - Error_Msg_N - ("\would be legal in Ada 2005 if " - & "Storage_Size of 0 given??", E); - end if; - end if; - end if; - - -- Case of composite types - - if Is_Composite_Type (E) then - - -- AI-117 requires that all new primitives of a tagged type must - -- inherit the convention of the full view of the type. Inherited - -- and overriding operations are defined to inherit the convention - -- of their parent or overridden subprogram (also specified in - -- AI-117), which will have occurred earlier (in Derive_Subprogram - -- and New_Overloaded_Entity). Here we set the convention of - -- primitives that are still convention Ada, which will ensure - -- that any new primitives inherit the type's convention. Class- - -- wide types can have a foreign convention inherited from their - -- specific type, but are excluded from this since they don't have - -- any associated primitives. - - if Is_Tagged_Type (E) - and then not Is_Class_Wide_Type (E) - and then Convention (E) /= Convention_Ada - then - declare - Prim_List : constant Elist_Id := Primitive_Operations (E); - Prim : Elmt_Id; - - begin - Prim := First_Elmt (Prim_List); - while Present (Prim) loop - if Convention (Node (Prim)) = Convention_Ada then - Set_Convention (Node (Prim), Convention (E)); - end if; - - Next_Elmt (Prim); - end loop; - end; - end if; - - -- If the type is a simple storage pool type, then this is where - -- we attempt to locate and validate its Allocate, Deallocate, and - -- Storage_Size operations (the first is required, and the latter - -- two are optional). We also verify that the full type for a - -- private type is allowed to be a simple storage pool type. - - if Present (Get_Rep_Pragma (E, Name_Simple_Storage_Pool_Type)) - and then (Is_Base_Type (E) or else Has_Private_Declaration (E)) - then - -- If the type is marked Has_Private_Declaration, then this is - -- a full type for a private type that was specified with the - -- pragma Simple_Storage_Pool_Type, and here we ensure that the - -- pragma is allowed for the full type (for example, it can't - -- be an array type, or a nonlimited record type). - - if Has_Private_Declaration (E) then - if (not Is_Record_Type (E) - or else not Is_Immutably_Limited_Type (E)) - and then not Is_Private_Type (E) - then - Error_Msg_Name_1 := Name_Simple_Storage_Pool_Type; - Error_Msg_N - ("pragma% can only apply to full type that is an " & - "explicitly limited type", E); - end if; - end if; - - Validate_Simple_Pool_Ops : declare - Pool_Type : Entity_Id renames E; - Address_Type : constant Entity_Id := RTE (RE_Address); - Stg_Cnt_Type : constant Entity_Id := RTE (RE_Storage_Count); - - procedure Validate_Simple_Pool_Op_Formal - (Pool_Op : Entity_Id; - Pool_Op_Formal : in out Entity_Id; - Expected_Mode : Formal_Kind; - Expected_Type : Entity_Id; - Formal_Name : String; - OK_Formal : in out Boolean); - -- Validate one formal Pool_Op_Formal of the candidate pool - -- operation Pool_Op. The formal must be of Expected_Type - -- and have mode Expected_Mode. OK_Formal will be set to - -- False if the formal doesn't match. If OK_Formal is False - -- on entry, then the formal will effectively be ignored - -- (because validation of the pool op has already failed). - -- Upon return, Pool_Op_Formal will be updated to the next - -- formal, if any. - - procedure Validate_Simple_Pool_Operation (Op_Name : Name_Id); - -- Search for and validate a simple pool operation with the - -- name Op_Name. If the name is Allocate, then there must be - -- exactly one such primitive operation for the simple pool - -- type. If the name is Deallocate or Storage_Size, then - -- there can be at most one such primitive operation. The - -- profile of the located primitive must conform to what - -- is expected for each operation. - - ------------------------------------ - -- Validate_Simple_Pool_Op_Formal -- - ------------------------------------ - - procedure Validate_Simple_Pool_Op_Formal - (Pool_Op : Entity_Id; - Pool_Op_Formal : in out Entity_Id; - Expected_Mode : Formal_Kind; - Expected_Type : Entity_Id; - Formal_Name : String; - OK_Formal : in out Boolean) - is - begin - -- If OK_Formal is False on entry, then simply ignore - -- the formal, because an earlier formal has already - -- been flagged. - - if not OK_Formal then - return; - - -- If no formal is passed in, then issue an error for a - -- missing formal. - - elsif not Present (Pool_Op_Formal) then - Error_Msg_NE - ("simple storage pool op missing formal " & - Formal_Name & " of type&", Pool_Op, Expected_Type); - OK_Formal := False; - - return; - end if; - - if Etype (Pool_Op_Formal) /= Expected_Type then - - -- If the pool type was expected for this formal, then - -- this will not be considered a candidate operation - -- for the simple pool, so we unset OK_Formal so that - -- the op and any later formals will be ignored. - - if Expected_Type = Pool_Type then - OK_Formal := False; - - return; - - else - Error_Msg_NE - ("wrong type for formal " & Formal_Name & - " of simple storage pool op; expected type&", - Pool_Op_Formal, Expected_Type); - end if; - end if; - - -- Issue error if formal's mode is not the expected one - - if Ekind (Pool_Op_Formal) /= Expected_Mode then - Error_Msg_N - ("wrong mode for formal of simple storage pool op", - Pool_Op_Formal); - end if; - - -- Advance to the next formal - - Next_Formal (Pool_Op_Formal); - end Validate_Simple_Pool_Op_Formal; - - ------------------------------------ - -- Validate_Simple_Pool_Operation -- - ------------------------------------ - - procedure Validate_Simple_Pool_Operation - (Op_Name : Name_Id) - is - Op : Entity_Id; - Found_Op : Entity_Id := Empty; - Formal : Entity_Id; - Is_OK : Boolean; - - begin - pragma Assert - (Op_Name = Name_Allocate - or else Op_Name = Name_Deallocate - or else Op_Name = Name_Storage_Size); - - Error_Msg_Name_1 := Op_Name; - - -- For each homonym declared immediately in the scope - -- of the simple storage pool type, determine whether - -- the homonym is an operation of the pool type, and, - -- if so, check that its profile is as expected for - -- a simple pool operation of that name. - - Op := Get_Name_Entity_Id (Op_Name); - while Present (Op) loop - if Ekind_In (Op, E_Function, E_Procedure) - and then Scope (Op) = Current_Scope - then - Formal := First_Entity (Op); - - Is_OK := True; - - -- The first parameter must be of the pool type - -- in order for the operation to qualify. - - if Op_Name = Name_Storage_Size then - Validate_Simple_Pool_Op_Formal - (Op, Formal, E_In_Parameter, Pool_Type, - "Pool", Is_OK); - else - Validate_Simple_Pool_Op_Formal - (Op, Formal, E_In_Out_Parameter, Pool_Type, - "Pool", Is_OK); - end if; - - -- If another operation with this name has already - -- been located for the type, then flag an error, - -- since we only allow the type to have a single - -- such primitive. - - if Present (Found_Op) and then Is_OK then - Error_Msg_NE - ("only one % operation allowed for " & - "simple storage pool type&", Op, Pool_Type); - end if; - - -- In the case of Allocate and Deallocate, a formal - -- of type System.Address is required. - - if Op_Name = Name_Allocate then - Validate_Simple_Pool_Op_Formal - (Op, Formal, E_Out_Parameter, - Address_Type, "Storage_Address", Is_OK); - elsif Op_Name = Name_Deallocate then - Validate_Simple_Pool_Op_Formal - (Op, Formal, E_In_Parameter, - Address_Type, "Storage_Address", Is_OK); - end if; - - -- In the case of Allocate and Deallocate, formals - -- of type Storage_Count are required as the third - -- and fourth parameters. - - if Op_Name /= Name_Storage_Size then - Validate_Simple_Pool_Op_Formal - (Op, Formal, E_In_Parameter, - Stg_Cnt_Type, "Size_In_Storage_Units", Is_OK); - Validate_Simple_Pool_Op_Formal - (Op, Formal, E_In_Parameter, - Stg_Cnt_Type, "Alignment", Is_OK); - end if; - - -- If no mismatched formals have been found (Is_OK) - -- and no excess formals are present, then this - -- operation has been validated, so record it. - - if not Present (Formal) and then Is_OK then - Found_Op := Op; - end if; - end if; - - Op := Homonym (Op); - end loop; - - -- There must be a valid Allocate operation for the type, - -- so issue an error if none was found. - - if Op_Name = Name_Allocate - and then not Present (Found_Op) - then - Error_Msg_N ("missing % operation for simple " & - "storage pool type", Pool_Type); - - elsif Present (Found_Op) then - - -- Simple pool operations can't be abstract - - if Is_Abstract_Subprogram (Found_Op) then - Error_Msg_N - ("simple storage pool operation must not be " & - "abstract", Found_Op); - end if; - - -- The Storage_Size operation must be a function with - -- Storage_Count as its result type. - - if Op_Name = Name_Storage_Size then - if Ekind (Found_Op) = E_Procedure then - Error_Msg_N - ("% operation must be a function", Found_Op); - - elsif Etype (Found_Op) /= Stg_Cnt_Type then - Error_Msg_NE - ("wrong result type for%, expected type&", - Found_Op, Stg_Cnt_Type); - end if; - - -- Allocate and Deallocate must be procedures - - elsif Ekind (Found_Op) = E_Function then - Error_Msg_N - ("% operation must be a procedure", Found_Op); - end if; - end if; - end Validate_Simple_Pool_Operation; - - -- Start of processing for Validate_Simple_Pool_Ops - - begin - Validate_Simple_Pool_Operation (Name_Allocate); - Validate_Simple_Pool_Operation (Name_Deallocate); - Validate_Simple_Pool_Operation (Name_Storage_Size); - end Validate_Simple_Pool_Ops; - end if; - end if; - - -- Now that all types from which E may depend are frozen, see if the - -- size is known at compile time, if it must be unsigned, or if - -- strict alignment is required - - Check_Compile_Time_Size (E); - Check_Unsigned_Type (E); - - if Base_Type (E) = E then - Check_Strict_Alignment (E); - end if; - - -- Do not allow a size clause for a type which does not have a size - -- that is known at compile time - - if Has_Size_Clause (E) - and then not Size_Known_At_Compile_Time (E) - then - -- Suppress this message if errors posted on E, even if we are - -- in all errors mode, since this is often a junk message - - if not Error_Posted (E) then - Error_Msg_N - ("size clause not allowed for variable length type", - Size_Clause (E)); - end if; - end if; - - -- Now we set/verify the representation information, in particular - -- the size and alignment values. This processing is not required for - -- generic types, since generic types do not play any part in code - -- generation, and so the size and alignment values for such types - -- are irrelevant. Ditto for types declared within a generic unit, - -- which may have components that depend on generic parameters, and - -- that will be recreated in an instance. - - if Inside_A_Generic then - null; - - -- Otherwise we call the layout procedure - - else - Layout_Type (E); - end if; - - -- If this is an access to subprogram whose designated type is itself - -- a subprogram type, the return type of this anonymous subprogram - -- type must be decorated as well. - - if Ekind (E) = E_Anonymous_Access_Subprogram_Type - and then Ekind (Designated_Type (E)) = E_Subprogram_Type - then - Layout_Type (Etype (Designated_Type (E))); - end if; - - -- If the type has a Defaut_Value/Default_Component_Value aspect, - -- this is where we analye the expression (after the type is frozen, - -- since in the case of Default_Value, we are analyzing with the - -- type itself, and we treat Default_Component_Value similarly for - -- the sake of uniformity). - - if Is_First_Subtype (E) and then Has_Default_Aspect (E) then - declare - Nam : Name_Id; - Exp : Node_Id; - Typ : Entity_Id; - - begin - if Is_Scalar_Type (E) then - Nam := Name_Default_Value; - Typ := E; - Exp := Default_Aspect_Value (Typ); - else - Nam := Name_Default_Component_Value; - Typ := Component_Type (E); - Exp := Default_Aspect_Component_Value (E); - end if; - - Analyze_And_Resolve (Exp, Typ); - - if Etype (Exp) /= Any_Type then - if not Is_Static_Expression (Exp) then - Error_Msg_Name_1 := Nam; - Flag_Non_Static_Expr - ("aspect% requires static expression", Exp); - end if; - end if; - end; - end if; - - -- End of freeze processing for type entities - end if; - - -- Here is where we logically freeze the current entity. If it has a - -- freeze node, then this is the point at which the freeze node is - -- linked into the result list. - - if Has_Delayed_Freeze (E) then - - -- If a freeze node is already allocated, use it, otherwise allocate - -- a new one. The preallocation happens in the case of anonymous base - -- types, where we preallocate so that we can set First_Subtype_Link. - -- Note that we reset the Sloc to the current freeze location. - - if Present (Freeze_Node (E)) then - F_Node := Freeze_Node (E); - Set_Sloc (F_Node, Loc); - - else - F_Node := New_Node (N_Freeze_Entity, Loc); - Set_Freeze_Node (E, F_Node); - Set_Access_Types_To_Process (F_Node, No_Elist); - Set_TSS_Elist (F_Node, No_Elist); - Set_Actions (F_Node, No_List); - end if; - - Set_Entity (F_Node, E); - Add_To_Result (F_Node); - - -- A final pass over record types with discriminants. If the type - -- has an incomplete declaration, there may be constrained access - -- subtypes declared elsewhere, which do not depend on the discrimi- - -- nants of the type, and which are used as component types (i.e. - -- the full view is a recursive type). The designated types of these - -- subtypes can only be elaborated after the type itself, and they - -- need an itype reference. - - if Ekind (E) = E_Record_Type - and then Has_Discriminants (E) - then - declare - Comp : Entity_Id; - IR : Node_Id; - Typ : Entity_Id; - - begin - Comp := First_Component (E); - while Present (Comp) loop - Typ := Etype (Comp); - - if Ekind (Comp) = E_Component - and then Is_Access_Type (Typ) - and then Scope (Typ) /= E - and then Base_Type (Designated_Type (Typ)) = E - and then Is_Itype (Designated_Type (Typ)) - then - IR := Make_Itype_Reference (Sloc (Comp)); - Set_Itype (IR, Designated_Type (Typ)); - Append (IR, Result); - end if; - - Next_Component (Comp); - end loop; - end; - end if; - end if; - - -- When a type is frozen, the first subtype of the type is frozen as - -- well (RM 13.14(15)). This has to be done after freezing the type, - -- since obviously the first subtype depends on its own base type. - - if Is_Type (E) then - Freeze_And_Append (First_Subtype (E), N, Result); - - -- If we just froze a tagged non-class wide record, then freeze the - -- corresponding class-wide type. This must be done after the tagged - -- type itself is frozen, because the class-wide type refers to the - -- tagged type which generates the class. - - if Is_Tagged_Type (E) - and then not Is_Class_Wide_Type (E) - and then Present (Class_Wide_Type (E)) - then - Freeze_And_Append (Class_Wide_Type (E), N, Result); - end if; - end if; - - Check_Debug_Info_Needed (E); - - -- Special handling for subprograms - - if Is_Subprogram (E) then - - -- If subprogram has address clause then reset Is_Public flag, since - -- we do not want the backend to generate external references. - - if Present (Address_Clause (E)) - and then not Is_Library_Level_Entity (E) - then - Set_Is_Public (E, False); - - -- If no address clause and not intrinsic, then for imported - -- subprogram in main unit, generate descriptor if we are in - -- Propagate_Exceptions mode. - - -- This is very odd code, it makes a null result, why ??? - - elsif Propagate_Exceptions - and then Is_Imported (E) - and then not Is_Intrinsic_Subprogram (E) - and then Convention (E) /= Convention_Stubbed - then - if Result = No_List then - Result := Empty_List; - end if; - end if; - end if; - - return Result; - end Freeze_Entity; - - ----------------------------- - -- Freeze_Enumeration_Type -- - ----------------------------- - - procedure Freeze_Enumeration_Type (Typ : Entity_Id) is - begin - -- By default, if no size clause is present, an enumeration type with - -- Convention C is assumed to interface to a C enum, and has integer - -- size. This applies to types. For subtypes, verify that its base - -- type has no size clause either. Treat other foreign conventions - -- in the same way, and also make sure alignment is set right. - - if Has_Foreign_Convention (Typ) - and then not Has_Size_Clause (Typ) - and then not Has_Size_Clause (Base_Type (Typ)) - and then Esize (Typ) < Standard_Integer_Size - then - Init_Esize (Typ, Standard_Integer_Size); - Set_Alignment (Typ, Alignment (Standard_Integer)); - - else - -- If the enumeration type interfaces to C, and it has a size clause - -- that specifies less than int size, it warrants a warning. The - -- user may intend the C type to be an enum or a char, so this is - -- not by itself an error that the Ada compiler can detect, but it - -- it is a worth a heads-up. For Boolean and Character types we - -- assume that the programmer has the proper C type in mind. - - if Convention (Typ) = Convention_C - and then Has_Size_Clause (Typ) - and then Esize (Typ) /= Esize (Standard_Integer) - and then not Is_Boolean_Type (Typ) - and then not Is_Character_Type (Typ) - then - Error_Msg_N - ("C enum types have the size of a C int??", Size_Clause (Typ)); - end if; - - Adjust_Esize_For_Alignment (Typ); - end if; - end Freeze_Enumeration_Type; - - ----------------------- - -- Freeze_Expression -- - ----------------------- - - procedure Freeze_Expression (N : Node_Id) is - In_Spec_Exp : constant Boolean := In_Spec_Expression; - Typ : Entity_Id; - Nam : Entity_Id; - Desig_Typ : Entity_Id; - P : Node_Id; - Parent_P : Node_Id; - - Freeze_Outside : Boolean := False; - -- This flag is set true if the entity must be frozen outside the - -- current subprogram. This happens in the case of expander generated - -- subprograms (_Init_Proc, _Input, _Output, _Read, _Write) which do - -- not freeze all entities like other bodies, but which nevertheless - -- may reference entities that have to be frozen before the body and - -- obviously cannot be frozen inside the body. - - function In_Exp_Body (N : Node_Id) return Boolean; - -- Given an N_Handled_Sequence_Of_Statements node N, determines whether - -- it is the handled statement sequence of an expander-generated - -- subprogram (init proc, stream subprogram, or renaming as body). - -- If so, this is not a freezing context. - - ----------------- - -- In_Exp_Body -- - ----------------- - - function In_Exp_Body (N : Node_Id) return Boolean is - P : Node_Id; - Id : Entity_Id; - - begin - if Nkind (N) = N_Subprogram_Body then - P := N; - else - P := Parent (N); - end if; - - if Nkind (P) /= N_Subprogram_Body then - return False; - - else - Id := Defining_Unit_Name (Specification (P)); - - -- Following complex conditional could use comments ??? - - if Nkind (Id) = N_Defining_Identifier - and then (Is_Init_Proc (Id) - or else Is_TSS (Id, TSS_Stream_Input) - or else Is_TSS (Id, TSS_Stream_Output) - or else Is_TSS (Id, TSS_Stream_Read) - or else Is_TSS (Id, TSS_Stream_Write) - or else Nkind_In (Original_Node (P), - N_Subprogram_Renaming_Declaration, - N_Expression_Function)) - then - return True; - else - return False; - end if; - end if; - end In_Exp_Body; - - -- Start of processing for Freeze_Expression - - begin - -- Immediate return if freezing is inhibited. This flag is set by the - -- analyzer to stop freezing on generated expressions that would cause - -- freezing if they were in the source program, but which are not - -- supposed to freeze, since they are created. - - if Must_Not_Freeze (N) then - return; - end if; - - -- If expression is non-static, then it does not freeze in a default - -- expression, see section "Handling of Default Expressions" in the - -- spec of package Sem for further details. Note that we have to make - -- sure that we actually have a real expression (if we have a subtype - -- indication, we can't test Is_Static_Expression!) However, we exclude - -- the case of the prefix of an attribute of a static scalar subtype - -- from this early return, because static subtype attributes should - -- always cause freezing, even in default expressions, but the attribute - -- may not have been marked as static yet (because in Resolve_Attribute, - -- the call to Eval_Attribute follows the call of Freeze_Expression on - -- the prefix). - - if In_Spec_Exp - and then Nkind (N) in N_Subexpr - and then not Is_Static_Expression (N) - and then (Nkind (Parent (N)) /= N_Attribute_Reference - or else not (Is_Entity_Name (N) - and then Is_Type (Entity (N)) - and then Is_Static_Subtype (Entity (N)))) - then - return; - end if; - - -- Freeze type of expression if not frozen already - - Typ := Empty; - - if Nkind (N) in N_Has_Etype then - if not Is_Frozen (Etype (N)) then - Typ := Etype (N); - - -- Base type may be an derived numeric type that is frozen at - -- the point of declaration, but first_subtype is still unfrozen. - - elsif not Is_Frozen (First_Subtype (Etype (N))) then - Typ := First_Subtype (Etype (N)); - end if; - end if; - - -- For entity name, freeze entity if not frozen already. A special - -- exception occurs for an identifier that did not come from source. - -- We don't let such identifiers freeze a non-internal entity, i.e. - -- an entity that did come from source, since such an identifier was - -- generated by the expander, and cannot have any semantic effect on - -- the freezing semantics. For example, this stops the parameter of - -- an initialization procedure from freezing the variable. - - if Is_Entity_Name (N) - and then not Is_Frozen (Entity (N)) - and then (Nkind (N) /= N_Identifier - or else Comes_From_Source (N) - or else not Comes_From_Source (Entity (N))) - then - Nam := Entity (N); - else - Nam := Empty; - end if; - - -- For an allocator freeze designated type if not frozen already - - -- For an aggregate whose component type is an access type, freeze the - -- designated type now, so that its freeze does not appear within the - -- loop that might be created in the expansion of the aggregate. If the - -- designated type is a private type without full view, the expression - -- cannot contain an allocator, so the type is not frozen. - - -- For a function, we freeze the entity when the subprogram declaration - -- is frozen, but a function call may appear in an initialization proc. - -- before the declaration is frozen. We need to generate the extra - -- formals, if any, to ensure that the expansion of the call includes - -- the proper actuals. This only applies to Ada subprograms, not to - -- imported ones. - - Desig_Typ := Empty; - - case Nkind (N) is - when N_Allocator => - Desig_Typ := Designated_Type (Etype (N)); - - when N_Aggregate => - if Is_Array_Type (Etype (N)) - and then Is_Access_Type (Component_Type (Etype (N))) - then - Desig_Typ := Designated_Type (Component_Type (Etype (N))); - end if; - - when N_Selected_Component | - N_Indexed_Component | - N_Slice => - - if Is_Access_Type (Etype (Prefix (N))) then - Desig_Typ := Designated_Type (Etype (Prefix (N))); - end if; - - when N_Identifier => - if Present (Nam) - and then Ekind (Nam) = E_Function - and then Nkind (Parent (N)) = N_Function_Call - and then Convention (Nam) = Convention_Ada - then - Create_Extra_Formals (Nam); - end if; - - when others => - null; - end case; - - if Desig_Typ /= Empty - and then (Is_Frozen (Desig_Typ) - or else (not Is_Fully_Defined (Desig_Typ))) - then - Desig_Typ := Empty; - end if; - - -- All done if nothing needs freezing - - if No (Typ) - and then No (Nam) - and then No (Desig_Typ) - then - return; - end if; - - -- Loop for looking at the right place to insert the freeze nodes, - -- exiting from the loop when it is appropriate to insert the freeze - -- node before the current node P. - - -- Also checks some special exceptions to the freezing rules. These - -- cases result in a direct return, bypassing the freeze action. - - P := N; - loop - Parent_P := Parent (P); - - -- If we don't have a parent, then we are not in a well-formed tree. - -- This is an unusual case, but there are some legitimate situations - -- in which this occurs, notably when the expressions in the range of - -- a type declaration are resolved. We simply ignore the freeze - -- request in this case. Is this right ??? - - if No (Parent_P) then - return; - end if; - - -- See if we have got to an appropriate point in the tree - - case Nkind (Parent_P) is - - -- A special test for the exception of (RM 13.14(8)) for the case - -- of per-object expressions (RM 3.8(18)) occurring in component - -- definition or a discrete subtype definition. Note that we test - -- for a component declaration which includes both cases we are - -- interested in, and furthermore the tree does not have explicit - -- nodes for either of these two constructs. - - when N_Component_Declaration => - - -- The case we want to test for here is an identifier that is - -- a per-object expression, this is either a discriminant that - -- appears in a context other than the component declaration - -- or it is a reference to the type of the enclosing construct. - - -- For either of these cases, we skip the freezing - - if not In_Spec_Expression - and then Nkind (N) = N_Identifier - and then (Present (Entity (N))) - then - -- We recognize the discriminant case by just looking for - -- a reference to a discriminant. It can only be one for - -- the enclosing construct. Skip freezing in this case. - - if Ekind (Entity (N)) = E_Discriminant then - return; - - -- For the case of a reference to the enclosing record, - -- (or task or protected type), we look for a type that - -- matches the current scope. - - elsif Entity (N) = Current_Scope then - return; - end if; - end if; - - -- If we have an enumeration literal that appears as the choice in - -- the aggregate of an enumeration representation clause, then - -- freezing does not occur (RM 13.14(10)). - - when N_Enumeration_Representation_Clause => - - -- The case we are looking for is an enumeration literal - - if (Nkind (N) = N_Identifier or Nkind (N) = N_Character_Literal) - and then Is_Enumeration_Type (Etype (N)) - then - -- If enumeration literal appears directly as the choice, - -- do not freeze (this is the normal non-overloaded case) - - if Nkind (Parent (N)) = N_Component_Association - and then First (Choices (Parent (N))) = N - then - return; - - -- If enumeration literal appears as the name of function - -- which is the choice, then also do not freeze. This - -- happens in the overloaded literal case, where the - -- enumeration literal is temporarily changed to a function - -- call for overloading analysis purposes. - - elsif Nkind (Parent (N)) = N_Function_Call - and then - Nkind (Parent (Parent (N))) = N_Component_Association - and then - First (Choices (Parent (Parent (N)))) = Parent (N) - then - return; - end if; - end if; - - -- Normally if the parent is a handled sequence of statements, - -- then the current node must be a statement, and that is an - -- appropriate place to insert a freeze node. - - when N_Handled_Sequence_Of_Statements => - - -- An exception occurs when the sequence of statements is for - -- an expander generated body that did not do the usual freeze - -- all operation. In this case we usually want to freeze - -- outside this body, not inside it, and we skip past the - -- subprogram body that we are inside. - - if In_Exp_Body (Parent_P) then - declare - Subp : constant Node_Id := Parent (Parent_P); - Spec : Entity_Id; - - begin - -- Freeze the entity only when it is declared inside the - -- body of the expander generated procedure. This case - -- is recognized by the scope of the entity or its type, - -- which is either the spec for some enclosing body, or - -- (in the case of init_procs, for which there are no - -- separate specs) the current scope. - - if Nkind (Subp) = N_Subprogram_Body then - Spec := Corresponding_Spec (Subp); - - if (Present (Typ) and then Scope (Typ) = Spec) - or else - (Present (Nam) and then Scope (Nam) = Spec) - then - exit; - - elsif Present (Typ) - and then Scope (Typ) = Current_Scope - and then Defining_Entity (Subp) = Current_Scope - then - exit; - end if; - end if; - - -- An expression function may act as a completion of - -- a function declaration. As such, it can reference - -- entities declared between the two views: - - -- Hidden []; -- 1 - -- function F return ...; - -- private - -- function Hidden return ...; - -- function F return ... is (Hidden); -- 2 - - -- Refering to the example above, freezing the expression - -- of F (2) would place Hidden's freeze node (1) in the - -- wrong place. Avoid explicit freezing and let the usual - -- scenarios do the job - for example, reaching the end - -- of the private declarations. - - if Nkind (Original_Node (Subp)) = - N_Expression_Function - then - null; - - -- Freeze outside the body - - else - Parent_P := Parent (Parent_P); - Freeze_Outside := True; - end if; - end; - - -- Here if normal case where we are in handled statement - -- sequence and want to do the insertion right there. - - else - exit; - end if; - - -- If parent is a body or a spec or a block, then the current node - -- is a statement or declaration and we can insert the freeze node - -- before it. - - when N_Block_Statement | - N_Entry_Body | - N_Package_Body | - N_Package_Specification | - N_Protected_Body | - N_Subprogram_Body | - N_Task_Body => exit; - - -- The expander is allowed to define types in any statements list, - -- so any of the following parent nodes also mark a freezing point - -- if the actual node is in a list of statements or declarations. - - when N_Abortable_Part | - N_Accept_Alternative | - N_And_Then | - N_Case_Statement_Alternative | - N_Compilation_Unit_Aux | - N_Conditional_Entry_Call | - N_Delay_Alternative | - N_Elsif_Part | - N_Entry_Call_Alternative | - N_Exception_Handler | - N_Extended_Return_Statement | - N_Freeze_Entity | - N_If_Statement | - N_Or_Else | - N_Selective_Accept | - N_Triggering_Alternative => - - exit when Is_List_Member (P); - - -- Note: The N_Loop_Statement is a special case. A type that - -- appears in the source can never be frozen in a loop (this - -- occurs only because of a loop expanded by the expander), so we - -- keep on going. Otherwise we terminate the search. Same is true - -- of any entity which comes from source. (if they have predefined - -- type, that type does not appear to come from source, but the - -- entity should not be frozen here). - - when N_Loop_Statement => - exit when not Comes_From_Source (Etype (N)) - and then (No (Nam) or else not Comes_From_Source (Nam)); - - -- For all other cases, keep looking at parents - - when others => - null; - end case; - - -- We fall through the case if we did not yet find the proper - -- place in the free for inserting the freeze node, so climb! - - P := Parent_P; - end loop; - - -- If the expression appears in a record or an initialization procedure, - -- the freeze nodes are collected and attached to the current scope, to - -- be inserted and analyzed on exit from the scope, to insure that - -- generated entities appear in the correct scope. If the expression is - -- a default for a discriminant specification, the scope is still void. - -- The expression can also appear in the discriminant part of a private - -- or concurrent type. - - -- If the expression appears in a constrained subcomponent of an - -- enclosing record declaration, the freeze nodes must be attached to - -- the outer record type so they can eventually be placed in the - -- enclosing declaration list. - - -- The other case requiring this special handling is if we are in a - -- default expression, since in that case we are about to freeze a - -- static type, and the freeze scope needs to be the outer scope, not - -- the scope of the subprogram with the default parameter. - - -- For default expressions and other spec expressions in generic units, - -- the Move_Freeze_Nodes mechanism (see sem_ch12.adb) takes care of - -- placing them at the proper place, after the generic unit. - - if (In_Spec_Exp and not Inside_A_Generic) - or else Freeze_Outside - or else (Is_Type (Current_Scope) - and then (not Is_Concurrent_Type (Current_Scope) - or else not Has_Completion (Current_Scope))) - or else Ekind (Current_Scope) = E_Void - then - declare - N : constant Node_Id := Current_Scope; - Freeze_Nodes : List_Id := No_List; - Pos : Int := Scope_Stack.Last; - - begin - if Present (Desig_Typ) then - Freeze_And_Append (Desig_Typ, N, Freeze_Nodes); - end if; - - if Present (Typ) then - Freeze_And_Append (Typ, N, Freeze_Nodes); - end if; - - if Present (Nam) then - Freeze_And_Append (Nam, N, Freeze_Nodes); - end if; - - -- The current scope may be that of a constrained component of - -- an enclosing record declaration, or of a loop of an enclosing - -- quantified expression, which is above the current scope in the - -- scope stack. Indeed in the context of a quantified expression, - -- a scope is created and pushed above the current scope in order - -- to emulate the loop-like behavior of the quantified expression. - -- If the expression is within a top-level pragma, as for a pre- - -- condition on a library-level subprogram, nothing to do. - - if not Is_Compilation_Unit (Current_Scope) - and then (Is_Record_Type (Scope (Current_Scope)) - or else Nkind (Parent (Current_Scope)) = - N_Quantified_Expression) - then - Pos := Pos - 1; - end if; - - if Is_Non_Empty_List (Freeze_Nodes) then - if No (Scope_Stack.Table (Pos).Pending_Freeze_Actions) then - Scope_Stack.Table (Pos).Pending_Freeze_Actions := - Freeze_Nodes; - else - Append_List (Freeze_Nodes, - Scope_Stack.Table (Pos).Pending_Freeze_Actions); - end if; - end if; - end; - - return; - end if; - - -- Now we have the right place to do the freezing. First, a special - -- adjustment, if we are in spec-expression analysis mode, these freeze - -- actions must not be thrown away (normally all inserted actions are - -- thrown away in this mode. However, the freeze actions are from static - -- expressions and one of the important reasons we are doing this - -- special analysis is to get these freeze actions. Therefore we turn - -- off the In_Spec_Expression mode to propagate these freeze actions. - -- This also means they get properly analyzed and expanded. - - In_Spec_Expression := False; - - -- Freeze the designated type of an allocator (RM 13.14(13)) - - if Present (Desig_Typ) then - Freeze_Before (P, Desig_Typ); - end if; - - -- Freeze type of expression (RM 13.14(10)). Note that we took care of - -- the enumeration representation clause exception in the loop above. - - if Present (Typ) then - Freeze_Before (P, Typ); - end if; - - -- Freeze name if one is present (RM 13.14(11)) - - if Present (Nam) then - Freeze_Before (P, Nam); - end if; - - -- Restore In_Spec_Expression flag - - In_Spec_Expression := In_Spec_Exp; - end Freeze_Expression; - - ----------------------------- - -- Freeze_Fixed_Point_Type -- - ----------------------------- - - -- Certain fixed-point types and subtypes, including implicit base types - -- and declared first subtypes, have not yet set up a range. This is - -- because the range cannot be set until the Small and Size values are - -- known, and these are not known till the type is frozen. - - -- To signal this case, Scalar_Range contains an unanalyzed syntactic range - -- whose bounds are unanalyzed real literals. This routine will recognize - -- this case, and transform this range node into a properly typed range - -- with properly analyzed and resolved values. - - procedure Freeze_Fixed_Point_Type (Typ : Entity_Id) is - Rng : constant Node_Id := Scalar_Range (Typ); - Lo : constant Node_Id := Low_Bound (Rng); - Hi : constant Node_Id := High_Bound (Rng); - Btyp : constant Entity_Id := Base_Type (Typ); - Brng : constant Node_Id := Scalar_Range (Btyp); - BLo : constant Node_Id := Low_Bound (Brng); - BHi : constant Node_Id := High_Bound (Brng); - Small : constant Ureal := Small_Value (Typ); - Loval : Ureal; - Hival : Ureal; - Atype : Entity_Id; - - Actual_Size : Nat; - - function Fsize (Lov, Hiv : Ureal) return Nat; - -- Returns size of type with given bounds. Also leaves these - -- bounds set as the current bounds of the Typ. - - ----------- - -- Fsize -- - ----------- - - function Fsize (Lov, Hiv : Ureal) return Nat is - begin - Set_Realval (Lo, Lov); - Set_Realval (Hi, Hiv); - return Minimum_Size (Typ); - end Fsize; - - -- Start of processing for Freeze_Fixed_Point_Type - - begin - -- If Esize of a subtype has not previously been set, set it now - - if Unknown_Esize (Typ) then - Atype := Ancestor_Subtype (Typ); - - if Present (Atype) then - Set_Esize (Typ, Esize (Atype)); - else - Set_Esize (Typ, Esize (Base_Type (Typ))); - end if; - end if; - - -- Immediate return if the range is already analyzed. This means that - -- the range is already set, and does not need to be computed by this - -- routine. - - if Analyzed (Rng) then - return; - end if; - - -- Immediate return if either of the bounds raises Constraint_Error - - if Raises_Constraint_Error (Lo) - or else Raises_Constraint_Error (Hi) - then - return; - end if; - - Loval := Realval (Lo); - Hival := Realval (Hi); - - -- Ordinary fixed-point case - - if Is_Ordinary_Fixed_Point_Type (Typ) then - - -- For the ordinary fixed-point case, we are allowed to fudge the - -- end-points up or down by small. Generally we prefer to fudge up, - -- i.e. widen the bounds for non-model numbers so that the end points - -- are included. However there are cases in which this cannot be - -- done, and indeed cases in which we may need to narrow the bounds. - -- The following circuit makes the decision. - - -- Note: our terminology here is that Incl_EP means that the bounds - -- are widened by Small if necessary to include the end points, and - -- Excl_EP means that the bounds are narrowed by Small to exclude the - -- end-points if this reduces the size. - - -- Note that in the Incl case, all we care about is including the - -- end-points. In the Excl case, we want to narrow the bounds as - -- much as permitted by the RM, to give the smallest possible size. - - Fudge : declare - Loval_Incl_EP : Ureal; - Hival_Incl_EP : Ureal; - - Loval_Excl_EP : Ureal; - Hival_Excl_EP : Ureal; - - Size_Incl_EP : Nat; - Size_Excl_EP : Nat; - - Model_Num : Ureal; - First_Subt : Entity_Id; - Actual_Lo : Ureal; - Actual_Hi : Ureal; - - begin - -- First step. Base types are required to be symmetrical. Right - -- now, the base type range is a copy of the first subtype range. - -- This will be corrected before we are done, but right away we - -- need to deal with the case where both bounds are non-negative. - -- In this case, we set the low bound to the negative of the high - -- bound, to make sure that the size is computed to include the - -- required sign. Note that we do not need to worry about the - -- case of both bounds negative, because the sign will be dealt - -- with anyway. Furthermore we can't just go making such a bound - -- symmetrical, since in a twos-complement system, there is an - -- extra negative value which could not be accommodated on the - -- positive side. - - if Typ = Btyp - and then not UR_Is_Negative (Loval) - and then Hival > Loval - then - Loval := -Hival; - Set_Realval (Lo, Loval); - end if; - - -- Compute the fudged bounds. If the number is a model number, - -- then we do nothing to include it, but we are allowed to backoff - -- to the next adjacent model number when we exclude it. If it is - -- not a model number then we straddle the two values with the - -- model numbers on either side. - - Model_Num := UR_Trunc (Loval / Small) * Small; - - if Loval = Model_Num then - Loval_Incl_EP := Model_Num; - else - Loval_Incl_EP := Model_Num - Small; - end if; - - -- The low value excluding the end point is Small greater, but - -- we do not do this exclusion if the low value is positive, - -- since it can't help the size and could actually hurt by - -- crossing the high bound. - - if UR_Is_Negative (Loval_Incl_EP) then - Loval_Excl_EP := Loval_Incl_EP + Small; - - -- If the value went from negative to zero, then we have the - -- case where Loval_Incl_EP is the model number just below - -- zero, so we want to stick to the negative value for the - -- base type to maintain the condition that the size will - -- include signed values. - - if Typ = Btyp - and then UR_Is_Zero (Loval_Excl_EP) - then - Loval_Excl_EP := Loval_Incl_EP; - end if; - - else - Loval_Excl_EP := Loval_Incl_EP; - end if; - - -- Similar processing for upper bound and high value - - Model_Num := UR_Trunc (Hival / Small) * Small; - - if Hival = Model_Num then - Hival_Incl_EP := Model_Num; - else - Hival_Incl_EP := Model_Num + Small; - end if; - - if UR_Is_Positive (Hival_Incl_EP) then - Hival_Excl_EP := Hival_Incl_EP - Small; - else - Hival_Excl_EP := Hival_Incl_EP; - end if; - - -- One further adjustment is needed. In the case of subtypes, we - -- cannot go outside the range of the base type, or we get - -- peculiarities, and the base type range is already set. This - -- only applies to the Incl values, since clearly the Excl values - -- are already as restricted as they are allowed to be. - - if Typ /= Btyp then - Loval_Incl_EP := UR_Max (Loval_Incl_EP, Realval (BLo)); - Hival_Incl_EP := UR_Min (Hival_Incl_EP, Realval (BHi)); - end if; - - -- Get size including and excluding end points - - Size_Incl_EP := Fsize (Loval_Incl_EP, Hival_Incl_EP); - Size_Excl_EP := Fsize (Loval_Excl_EP, Hival_Excl_EP); - - -- No need to exclude end-points if it does not reduce size - - if Fsize (Loval_Incl_EP, Hival_Excl_EP) = Size_Excl_EP then - Loval_Excl_EP := Loval_Incl_EP; - end if; - - if Fsize (Loval_Excl_EP, Hival_Incl_EP) = Size_Excl_EP then - Hival_Excl_EP := Hival_Incl_EP; - end if; - - -- Now we set the actual size to be used. We want to use the - -- bounds fudged up to include the end-points but only if this - -- can be done without violating a specifically given size - -- size clause or causing an unacceptable increase in size. - - -- Case of size clause given - - if Has_Size_Clause (Typ) then - - -- Use the inclusive size only if it is consistent with - -- the explicitly specified size. - - if Size_Incl_EP <= RM_Size (Typ) then - Actual_Lo := Loval_Incl_EP; - Actual_Hi := Hival_Incl_EP; - Actual_Size := Size_Incl_EP; - - -- If the inclusive size is too large, we try excluding - -- the end-points (will be caught later if does not work). - - else - Actual_Lo := Loval_Excl_EP; - Actual_Hi := Hival_Excl_EP; - Actual_Size := Size_Excl_EP; - end if; - - -- Case of size clause not given - - else - -- If we have a base type whose corresponding first subtype - -- has an explicit size that is large enough to include our - -- end-points, then do so. There is no point in working hard - -- to get a base type whose size is smaller than the specified - -- size of the first subtype. - - First_Subt := First_Subtype (Typ); - - if Has_Size_Clause (First_Subt) - and then Size_Incl_EP <= Esize (First_Subt) - then - Actual_Size := Size_Incl_EP; - Actual_Lo := Loval_Incl_EP; - Actual_Hi := Hival_Incl_EP; - - -- If excluding the end-points makes the size smaller and - -- results in a size of 8,16,32,64, then we take the smaller - -- size. For the 64 case, this is compulsory. For the other - -- cases, it seems reasonable. We like to include end points - -- if we can, but not at the expense of moving to the next - -- natural boundary of size. - - elsif Size_Incl_EP /= Size_Excl_EP - and then Addressable (Size_Excl_EP) - then - Actual_Size := Size_Excl_EP; - Actual_Lo := Loval_Excl_EP; - Actual_Hi := Hival_Excl_EP; - - -- Otherwise we can definitely include the end points - - else - Actual_Size := Size_Incl_EP; - Actual_Lo := Loval_Incl_EP; - Actual_Hi := Hival_Incl_EP; - end if; - - -- One pathological case: normally we never fudge a low bound - -- down, since it would seem to increase the size (if it has - -- any effect), but for ranges containing single value, or no - -- values, the high bound can be small too large. Consider: - - -- type t is delta 2.0**(-14) - -- range 131072.0 .. 0; - - -- That lower bound is *just* outside the range of 32 bits, and - -- does need fudging down in this case. Note that the bounds - -- will always have crossed here, since the high bound will be - -- fudged down if necessary, as in the case of: - - -- type t is delta 2.0**(-14) - -- range 131072.0 .. 131072.0; - - -- So we detect the situation by looking for crossed bounds, - -- and if the bounds are crossed, and the low bound is greater - -- than zero, we will always back it off by small, since this - -- is completely harmless. - - if Actual_Lo > Actual_Hi then - if UR_Is_Positive (Actual_Lo) then - Actual_Lo := Loval_Incl_EP - Small; - Actual_Size := Fsize (Actual_Lo, Actual_Hi); - - -- And of course, we need to do exactly the same parallel - -- fudge for flat ranges in the negative region. - - elsif UR_Is_Negative (Actual_Hi) then - Actual_Hi := Hival_Incl_EP + Small; - Actual_Size := Fsize (Actual_Lo, Actual_Hi); - end if; - end if; - end if; - - Set_Realval (Lo, Actual_Lo); - Set_Realval (Hi, Actual_Hi); - end Fudge; - - -- For the decimal case, none of this fudging is required, since there - -- are no end-point problems in the decimal case (the end-points are - -- always included). - - else - Actual_Size := Fsize (Loval, Hival); - end if; - - -- At this stage, the actual size has been calculated and the proper - -- required bounds are stored in the low and high bounds. - - if Actual_Size > 64 then - Error_Msg_Uint_1 := UI_From_Int (Actual_Size); - Error_Msg_N - ("size required (^) for type& too large, maximum allowed is 64", - Typ); - Actual_Size := 64; - end if; - - -- Check size against explicit given size - - if Has_Size_Clause (Typ) then - if Actual_Size > RM_Size (Typ) then - Error_Msg_Uint_1 := RM_Size (Typ); - Error_Msg_Uint_2 := UI_From_Int (Actual_Size); - Error_Msg_NE - ("size given (^) for type& too small, minimum allowed is ^", - Size_Clause (Typ), Typ); - - else - Actual_Size := UI_To_Int (Esize (Typ)); - end if; - - -- Increase size to next natural boundary if no size clause given - - else - if Actual_Size <= 8 then - Actual_Size := 8; - elsif Actual_Size <= 16 then - Actual_Size := 16; - elsif Actual_Size <= 32 then - Actual_Size := 32; - else - Actual_Size := 64; - end if; - - Init_Esize (Typ, Actual_Size); - Adjust_Esize_For_Alignment (Typ); - end if; - - -- If we have a base type, then expand the bounds so that they extend to - -- the full width of the allocated size in bits, to avoid junk range - -- checks on intermediate computations. - - if Base_Type (Typ) = Typ then - Set_Realval (Lo, -(Small * (Uint_2 ** (Actual_Size - 1)))); - Set_Realval (Hi, (Small * (Uint_2 ** (Actual_Size - 1) - 1))); - end if; - - -- Final step is to reanalyze the bounds using the proper type - -- and set the Corresponding_Integer_Value fields of the literals. - - Set_Etype (Lo, Empty); - Set_Analyzed (Lo, False); - Analyze (Lo); - - -- Resolve with universal fixed if the base type, and the base type if - -- it is a subtype. Note we can't resolve the base type with itself, - -- that would be a reference before definition. - - if Typ = Btyp then - Resolve (Lo, Universal_Fixed); - else - Resolve (Lo, Btyp); - end if; - - -- Set corresponding integer value for bound - - Set_Corresponding_Integer_Value - (Lo, UR_To_Uint (Realval (Lo) / Small)); - - -- Similar processing for high bound - - Set_Etype (Hi, Empty); - Set_Analyzed (Hi, False); - Analyze (Hi); - - if Typ = Btyp then - Resolve (Hi, Universal_Fixed); - else - Resolve (Hi, Btyp); - end if; - - Set_Corresponding_Integer_Value - (Hi, UR_To_Uint (Realval (Hi) / Small)); - - -- Set type of range to correspond to bounds - - Set_Etype (Rng, Etype (Lo)); - - -- Set Esize to calculated size if not set already - - if Unknown_Esize (Typ) then - Init_Esize (Typ, Actual_Size); - end if; - - -- Set RM_Size if not already set. If already set, check value - - declare - Minsiz : constant Uint := UI_From_Int (Minimum_Size (Typ)); - - begin - if RM_Size (Typ) /= Uint_0 then - if RM_Size (Typ) < Minsiz then - Error_Msg_Uint_1 := RM_Size (Typ); - Error_Msg_Uint_2 := Minsiz; - Error_Msg_NE - ("size given (^) for type& too small, minimum allowed is ^", - Size_Clause (Typ), Typ); - end if; - - else - Set_RM_Size (Typ, Minsiz); - end if; - end; - end Freeze_Fixed_Point_Type; - - ------------------ - -- Freeze_Itype -- - ------------------ - - procedure Freeze_Itype (T : Entity_Id; N : Node_Id) is - L : List_Id; - - begin - Set_Has_Delayed_Freeze (T); - L := Freeze_Entity (T, N); - - if Is_Non_Empty_List (L) then - Insert_Actions (N, L); - end if; - end Freeze_Itype; - - -------------------------- - -- Freeze_Static_Object -- - -------------------------- - - procedure Freeze_Static_Object (E : Entity_Id) is - - Cannot_Be_Static : exception; - -- Exception raised if the type of a static object cannot be made - -- static. This happens if the type depends on non-global objects. - - procedure Ensure_Expression_Is_SA (N : Node_Id); - -- Called to ensure that an expression used as part of a type definition - -- is statically allocatable, which means that the expression type is - -- statically allocatable, and the expression is either static, or a - -- reference to a library level constant. - - procedure Ensure_Type_Is_SA (Typ : Entity_Id); - -- Called to mark a type as static, checking that it is possible - -- to set the type as static. If it is not possible, then the - -- exception Cannot_Be_Static is raised. - - ----------------------------- - -- Ensure_Expression_Is_SA -- - ----------------------------- - - procedure Ensure_Expression_Is_SA (N : Node_Id) is - Ent : Entity_Id; - - begin - Ensure_Type_Is_SA (Etype (N)); - - if Is_Static_Expression (N) then - return; - - elsif Nkind (N) = N_Identifier then - Ent := Entity (N); - - if Present (Ent) - and then Ekind (Ent) = E_Constant - and then Is_Library_Level_Entity (Ent) - then - return; - end if; - end if; - - raise Cannot_Be_Static; - end Ensure_Expression_Is_SA; - - ----------------------- - -- Ensure_Type_Is_SA -- - ----------------------- - - procedure Ensure_Type_Is_SA (Typ : Entity_Id) is - N : Node_Id; - C : Entity_Id; - - begin - -- If type is library level, we are all set - - if Is_Library_Level_Entity (Typ) then - return; - end if; - - -- We are also OK if the type already marked as statically allocated, - -- which means we processed it before. - - if Is_Statically_Allocated (Typ) then - return; - end if; - - -- Mark type as statically allocated - - Set_Is_Statically_Allocated (Typ); - - -- Check that it is safe to statically allocate this type - - if Is_Scalar_Type (Typ) or else Is_Real_Type (Typ) then - Ensure_Expression_Is_SA (Type_Low_Bound (Typ)); - Ensure_Expression_Is_SA (Type_High_Bound (Typ)); - - elsif Is_Array_Type (Typ) then - N := First_Index (Typ); - while Present (N) loop - Ensure_Type_Is_SA (Etype (N)); - Next_Index (N); - end loop; - - Ensure_Type_Is_SA (Component_Type (Typ)); - - elsif Is_Access_Type (Typ) then - if Ekind (Designated_Type (Typ)) = E_Subprogram_Type then - - declare - F : Entity_Id; - T : constant Entity_Id := Etype (Designated_Type (Typ)); - - begin - if T /= Standard_Void_Type then - Ensure_Type_Is_SA (T); - end if; - - F := First_Formal (Designated_Type (Typ)); - while Present (F) loop - Ensure_Type_Is_SA (Etype (F)); - Next_Formal (F); - end loop; - end; - - else - Ensure_Type_Is_SA (Designated_Type (Typ)); - end if; - - elsif Is_Record_Type (Typ) then - C := First_Entity (Typ); - while Present (C) loop - if Ekind (C) = E_Discriminant - or else Ekind (C) = E_Component - then - Ensure_Type_Is_SA (Etype (C)); - - elsif Is_Type (C) then - Ensure_Type_Is_SA (C); - end if; - - Next_Entity (C); - end loop; - - elsif Ekind (Typ) = E_Subprogram_Type then - Ensure_Type_Is_SA (Etype (Typ)); - - C := First_Formal (Typ); - while Present (C) loop - Ensure_Type_Is_SA (Etype (C)); - Next_Formal (C); - end loop; - - else - raise Cannot_Be_Static; - end if; - end Ensure_Type_Is_SA; - - -- Start of processing for Freeze_Static_Object - - begin - Ensure_Type_Is_SA (Etype (E)); - - exception - when Cannot_Be_Static => - - -- If the object that cannot be static is imported or exported, then - -- issue an error message saying that this object cannot be imported - -- or exported. If it has an address clause it is an overlay in the - -- current partition and the static requirement is not relevant. - -- Do not issue any error message when ignoring rep clauses. - - if Ignore_Rep_Clauses then - null; - - elsif Is_Imported (E) then - if No (Address_Clause (E)) then - Error_Msg_N - ("& cannot be imported (local type is not constant)", E); - end if; - - -- Otherwise must be exported, something is wrong if compiler - -- is marking something as statically allocated which cannot be). - - else pragma Assert (Is_Exported (E)); - Error_Msg_N - ("& cannot be exported (local type is not constant)", E); - end if; - end Freeze_Static_Object; - - ----------------------- - -- Freeze_Subprogram -- - ----------------------- - - procedure Freeze_Subprogram (E : Entity_Id) is - Retype : Entity_Id; - F : Entity_Id; - - begin - -- Subprogram may not have an address clause unless it is imported - - if Present (Address_Clause (E)) then - if not Is_Imported (E) then - Error_Msg_N - ("address clause can only be given " & - "for imported subprogram", - Name (Address_Clause (E))); - end if; - end if; - - -- Reset the Pure indication on an imported subprogram unless an - -- explicit Pure_Function pragma was present. We do this because - -- otherwise it is an insidious error to call a non-pure function from - -- pure unit and have calls mysteriously optimized away. What happens - -- here is that the Import can bypass the normal check to ensure that - -- pure units call only pure subprograms. - - if Is_Imported (E) - and then Is_Pure (E) - and then not Has_Pragma_Pure_Function (E) - then - Set_Is_Pure (E, False); - end if; - - -- For non-foreign convention subprograms, this is where we create - -- the extra formals (for accessibility level and constrained bit - -- information). We delay this till the freeze point precisely so - -- that we know the convention! - - if not Has_Foreign_Convention (E) then - Create_Extra_Formals (E); - Set_Mechanisms (E); - - -- If this is convention Ada and a Valued_Procedure, that's odd - - if Ekind (E) = E_Procedure - and then Is_Valued_Procedure (E) - and then Convention (E) = Convention_Ada - and then Warn_On_Export_Import - then - Error_Msg_N - ("??Valued_Procedure has no effect for convention Ada", E); - Set_Is_Valued_Procedure (E, False); - end if; - - -- Case of foreign convention - - else - Set_Mechanisms (E); - - -- For foreign conventions, warn about return of an - -- unconstrained array. - - -- Note: we *do* allow a return by descriptor for the VMS case, - -- though here there is probably more to be done ??? - - if Ekind (E) = E_Function then - Retype := Underlying_Type (Etype (E)); - - -- If no return type, probably some other error, e.g. a - -- missing full declaration, so ignore. - - if No (Retype) then - null; - - -- If the return type is generic, we have emitted a warning - -- earlier on, and there is nothing else to check here. Specific - -- instantiations may lead to erroneous behavior. - - elsif Is_Generic_Type (Etype (E)) then - null; - - -- Display warning if returning unconstrained array - - elsif Is_Array_Type (Retype) - and then not Is_Constrained (Retype) - - -- Exclude cases where descriptor mechanism is set, since the - -- VMS descriptor mechanisms allow such unconstrained returns. - - and then Mechanism (E) not in Descriptor_Codes - - -- Check appropriate warning is enabled (should we check for - -- Warnings (Off) on specific entities here, probably so???) - - and then Warn_On_Export_Import - - -- Exclude the VM case, since return of unconstrained arrays - -- is properly handled in both the JVM and .NET cases. - - and then VM_Target = No_VM - then - Error_Msg_N - ("?x?foreign convention function& should not return " & - "unconstrained array", E); - return; - end if; - end if; - - -- If any of the formals for an exported foreign convention - -- subprogram have defaults, then emit an appropriate warning since - -- this is odd (default cannot be used from non-Ada code) - - if Is_Exported (E) then - F := First_Formal (E); - while Present (F) loop - if Warn_On_Export_Import - and then Present (Default_Value (F)) - then - Error_Msg_N - ("?x?parameter cannot be defaulted in non-Ada call", - Default_Value (F)); - end if; - - Next_Formal (F); - end loop; - end if; - end if; - - -- For VMS, descriptor mechanisms for parameters are allowed only for - -- imported/exported subprograms. Moreover, the NCA descriptor is not - -- allowed for parameters of exported subprograms. - - if OpenVMS_On_Target then - if Is_Exported (E) then - F := First_Formal (E); - while Present (F) loop - if Mechanism (F) = By_Descriptor_NCA then - Error_Msg_N - ("'N'C'A' descriptor for parameter not permitted", F); - Error_Msg_N - ("\can only be used for imported subprogram", F); - end if; - - Next_Formal (F); - end loop; - - elsif not Is_Imported (E) then - F := First_Formal (E); - while Present (F) loop - if Mechanism (F) in Descriptor_Codes then - Error_Msg_N - ("descriptor mechanism for parameter not permitted", F); - Error_Msg_N - ("\can only be used for imported/exported subprogram", F); - end if; - - Next_Formal (F); - end loop; - end if; - end if; - - -- Pragma Inline_Always is disallowed for dispatching subprograms - -- because the address of such subprograms is saved in the dispatch - -- table to support dispatching calls, and dispatching calls cannot - -- be inlined. This is consistent with the restriction against using - -- 'Access or 'Address on an Inline_Always subprogram. - - if Is_Dispatching_Operation (E) - and then Has_Pragma_Inline_Always (E) - then - Error_Msg_N - ("pragma Inline_Always not allowed for dispatching subprograms", E); - end if; - - -- Because of the implicit representation of inherited predefined - -- operators in the front-end, the overriding status of the operation - -- may be affected when a full view of a type is analyzed, and this is - -- not captured by the analysis of the corresponding type declaration. - -- Therefore the correctness of a not-overriding indicator must be - -- rechecked when the subprogram is frozen. - - if Nkind (E) = N_Defining_Operator_Symbol - and then not Error_Posted (Parent (E)) - then - Check_Overriding_Indicator (E, Empty, Is_Primitive (E)); - end if; - end Freeze_Subprogram; - - ---------------------- - -- Is_Fully_Defined -- - ---------------------- - - function Is_Fully_Defined (T : Entity_Id) return Boolean is - begin - if Ekind (T) = E_Class_Wide_Type then - return Is_Fully_Defined (Etype (T)); - - elsif Is_Array_Type (T) then - return Is_Fully_Defined (Component_Type (T)); - - elsif Is_Record_Type (T) - and not Is_Private_Type (T) - then - -- Verify that the record type has no components with private types - -- without completion. - - declare - Comp : Entity_Id; - - begin - Comp := First_Component (T); - while Present (Comp) loop - if not Is_Fully_Defined (Etype (Comp)) then - return False; - end if; - - Next_Component (Comp); - end loop; - return True; - end; - - -- For the designated type of an access to subprogram, all types in - -- the profile must be fully defined. - - elsif Ekind (T) = E_Subprogram_Type then - declare - F : Entity_Id; - - begin - F := First_Formal (T); - while Present (F) loop - if not Is_Fully_Defined (Etype (F)) then - return False; - end if; - - Next_Formal (F); - end loop; - - return Is_Fully_Defined (Etype (T)); - end; - - else - return not Is_Private_Type (T) - or else Present (Full_View (Base_Type (T))); - end if; - end Is_Fully_Defined; - - --------------------------------- - -- Process_Default_Expressions -- - --------------------------------- - - procedure Process_Default_Expressions - (E : Entity_Id; - After : in out Node_Id) - is - Loc : constant Source_Ptr := Sloc (E); - Dbody : Node_Id; - Formal : Node_Id; - Dcopy : Node_Id; - Dnam : Entity_Id; - - begin - Set_Default_Expressions_Processed (E); - - -- A subprogram instance and its associated anonymous subprogram share - -- their signature. The default expression functions are defined in the - -- wrapper packages for the anonymous subprogram, and should not be - -- generated again for the instance. - - if Is_Generic_Instance (E) - and then Present (Alias (E)) - and then Default_Expressions_Processed (Alias (E)) - then - return; - end if; - - Formal := First_Formal (E); - while Present (Formal) loop - if Present (Default_Value (Formal)) then - - -- We work with a copy of the default expression because we - -- do not want to disturb the original, since this would mess - -- up the conformance checking. - - Dcopy := New_Copy_Tree (Default_Value (Formal)); - - -- The analysis of the expression may generate insert actions, - -- which of course must not be executed. We wrap those actions - -- in a procedure that is not called, and later on eliminated. - -- The following cases have no side-effects, and are analyzed - -- directly. - - if Nkind (Dcopy) = N_Identifier - or else Nkind (Dcopy) = N_Expanded_Name - or else Nkind (Dcopy) = N_Integer_Literal - or else (Nkind (Dcopy) = N_Real_Literal - and then not Vax_Float (Etype (Dcopy))) - or else Nkind (Dcopy) = N_Character_Literal - or else Nkind (Dcopy) = N_String_Literal - or else Known_Null (Dcopy) - or else (Nkind (Dcopy) = N_Attribute_Reference - and then - Attribute_Name (Dcopy) = Name_Null_Parameter) - then - - -- If there is no default function, we must still do a full - -- analyze call on the default value, to ensure that all error - -- checks are performed, e.g. those associated with static - -- evaluation. Note: this branch will always be taken if the - -- analyzer is turned off (but we still need the error checks). - - -- Note: the setting of parent here is to meet the requirement - -- that we can only analyze the expression while attached to - -- the tree. Really the requirement is that the parent chain - -- be set, we don't actually need to be in the tree. - - Set_Parent (Dcopy, Declaration_Node (Formal)); - Analyze (Dcopy); - - -- Default expressions are resolved with their own type if the - -- context is generic, to avoid anomalies with private types. - - if Ekind (Scope (E)) = E_Generic_Package then - Resolve (Dcopy); - else - Resolve (Dcopy, Etype (Formal)); - end if; - - -- If that resolved expression will raise constraint error, - -- then flag the default value as raising constraint error. - -- This allows a proper error message on the calls. - - if Raises_Constraint_Error (Dcopy) then - Set_Raises_Constraint_Error (Default_Value (Formal)); - end if; - - -- If the default is a parameterless call, we use the name of - -- the called function directly, and there is no body to build. - - elsif Nkind (Dcopy) = N_Function_Call - and then No (Parameter_Associations (Dcopy)) - then - null; - - -- Else construct and analyze the body of a wrapper procedure - -- that contains an object declaration to hold the expression. - -- Given that this is done only to complete the analysis, it - -- simpler to build a procedure than a function which might - -- involve secondary stack expansion. - - else - Dnam := Make_Temporary (Loc, 'D'); - - Dbody := - Make_Subprogram_Body (Loc, - Specification => - Make_Procedure_Specification (Loc, - Defining_Unit_Name => Dnam), - - Declarations => New_List ( - Make_Object_Declaration (Loc, - Defining_Identifier => Make_Temporary (Loc, 'T'), - Object_Definition => - New_Occurrence_Of (Etype (Formal), Loc), - Expression => New_Copy_Tree (Dcopy))), - - Handled_Statement_Sequence => - Make_Handled_Sequence_Of_Statements (Loc, - Statements => Empty_List)); - - Set_Scope (Dnam, Scope (E)); - Set_Assignment_OK (First (Declarations (Dbody))); - Set_Is_Eliminated (Dnam); - Insert_After (After, Dbody); - Analyze (Dbody); - After := Dbody; - end if; - end if; - - Next_Formal (Formal); - end loop; - end Process_Default_Expressions; - - ---------------------------------------- - -- Set_Component_Alignment_If_Not_Set -- - ---------------------------------------- - - procedure Set_Component_Alignment_If_Not_Set (Typ : Entity_Id) is - begin - -- Ignore if not base type, subtypes don't need anything - - if Typ /= Base_Type (Typ) then - return; - end if; - - -- Do not override existing representation - - if Is_Packed (Typ) then - return; - - elsif Has_Specified_Layout (Typ) then - return; - - elsif Component_Alignment (Typ) /= Calign_Default then - return; - - else - Set_Component_Alignment - (Typ, Scope_Stack.Table - (Scope_Stack.Last).Component_Alignment_Default); - end if; - end Set_Component_Alignment_If_Not_Set; - - ------------------ - -- Undelay_Type -- - ------------------ - - procedure Undelay_Type (T : Entity_Id) is - begin - Set_Has_Delayed_Freeze (T, False); - Set_Freeze_Node (T, Empty); - - -- Since we don't want T to have a Freeze_Node, we don't want its - -- Full_View or Corresponding_Record_Type to have one either. - - -- ??? Fundamentally, this whole handling is a kludge. What we really - -- want is to be sure that for an Itype that's part of record R and is a - -- subtype of type T, that it's frozen after the later of the freeze - -- points of R and T. We have no way of doing that directly, so what we - -- do is force most such Itypes to be frozen as part of freezing R via - -- this procedure and only delay the ones that need to be delayed - -- (mostly the designated types of access types that are defined as part - -- of the record). - - if Is_Private_Type (T) - and then Present (Full_View (T)) - and then Is_Itype (Full_View (T)) - and then Is_Record_Type (Scope (Full_View (T))) - then - Undelay_Type (Full_View (T)); - end if; - - if Is_Concurrent_Type (T) - and then Present (Corresponding_Record_Type (T)) - and then Is_Itype (Corresponding_Record_Type (T)) - and then Is_Record_Type (Scope (Corresponding_Record_Type (T))) - then - Undelay_Type (Corresponding_Record_Type (T)); - end if; - end Undelay_Type; - - ------------------ - -- Warn_Overlay -- - ------------------ - - procedure Warn_Overlay - (Expr : Node_Id; - Typ : Entity_Id; - Nam : Entity_Id) - is - Ent : constant Entity_Id := Entity (Nam); - -- The object to which the address clause applies - - Init : Node_Id; - Old : Entity_Id := Empty; - Decl : Node_Id; - - begin - -- No warning if address clause overlay warnings are off - - if not Address_Clause_Overlay_Warnings then - return; - end if; - - -- No warning if there is an explicit initialization - - Init := Original_Node (Expression (Declaration_Node (Ent))); - - if Present (Init) and then Comes_From_Source (Init) then - return; - end if; - - -- We only give the warning for non-imported entities of a type for - -- which a non-null base init proc is defined, or for objects of access - -- types with implicit null initialization, or when Normalize_Scalars - -- applies and the type is scalar or a string type (the latter being - -- tested for because predefined String types are initialized by inline - -- code rather than by an init_proc). Note that we do not give the - -- warning for Initialize_Scalars, since we suppressed initialization - -- in this case. Also, do not warn if Suppress_Initialization is set. - - if Present (Expr) - and then not Is_Imported (Ent) - and then not Initialization_Suppressed (Typ) - and then (Has_Non_Null_Base_Init_Proc (Typ) - or else Is_Access_Type (Typ) - or else (Normalize_Scalars - and then (Is_Scalar_Type (Typ) - or else Is_String_Type (Typ)))) - then - if Nkind (Expr) = N_Attribute_Reference - and then Is_Entity_Name (Prefix (Expr)) - then - Old := Entity (Prefix (Expr)); - - elsif Is_Entity_Name (Expr) - and then Ekind (Entity (Expr)) = E_Constant - then - Decl := Declaration_Node (Entity (Expr)); - - if Nkind (Decl) = N_Object_Declaration - and then Present (Expression (Decl)) - and then Nkind (Expression (Decl)) = N_Attribute_Reference - and then Is_Entity_Name (Prefix (Expression (Decl))) - then - Old := Entity (Prefix (Expression (Decl))); - - elsif Nkind (Expr) = N_Function_Call then - return; - end if; - - -- A function call (most likely to To_Address) is probably not an - -- overlay, so skip warning. Ditto if the function call was inlined - -- and transformed into an entity. - - elsif Nkind (Original_Node (Expr)) = N_Function_Call then - return; - end if; - - Decl := Next (Parent (Expr)); - - -- If a pragma Import follows, we assume that it is for the current - -- target of the address clause, and skip the warning. - - if Present (Decl) - and then Nkind (Decl) = N_Pragma - and then Pragma_Name (Decl) = Name_Import - then - return; - end if; - - if Present (Old) then - Error_Msg_Node_2 := Old; - Error_Msg_N - ("default initialization of & may modify &??", - Nam); - else - Error_Msg_N - ("default initialization of & may modify overlaid storage??", - Nam); - end if; - - -- Add friendly warning if initialization comes from a packed array - -- component. - - if Is_Record_Type (Typ) then - declare - Comp : Entity_Id; - - begin - Comp := First_Component (Typ); - while Present (Comp) loop - if Nkind (Parent (Comp)) = N_Component_Declaration - and then Present (Expression (Parent (Comp))) - then - exit; - elsif Is_Array_Type (Etype (Comp)) - and then Present (Packed_Array_Type (Etype (Comp))) - then - Error_Msg_NE - ("\packed array component& " & - "will be initialized to zero??", - Nam, Comp); - exit; - else - Next_Component (Comp); - end if; - end loop; - end; - end if; - - Error_Msg_N - ("\use pragma Import for & to " & - "suppress initialization (RM B.1(24))??", - Nam); - end if; - end Warn_Overlay; - -end Freeze; |