[multiple changes]

2010-10-26  Javier Miranda  <miranda@adacore.com>

	* einfo.ads, einfo.adb (Is_Overriding_Operation): Removed.
	(Set_Is_Overriding_Operation): Removed.
	* sem_ch3.adb (Check_Abstract_Overriding): Remove redundant call to
	Is_Overriding_Operation.
	* exp_ch7.adb (Check_Visibly_Controlled): Remove redundant call to
	Is_Overriding_Operation.
	* sem_ch7.adb (Declare_Inherited_Private_Subprograms): Remove redundant
	call to Set_Is_Overriding_Operation.
	* sem_util.adb (Collect_Primitive_Operations): Replace test on
	Is_Overriding_Operation by test on the presence of attribute
	Overridden_Operation.
	(Original_Corresponding_Operation): Remove redundant call to attribute
	Is_Overriding_Operation.
	* sem_ch6.adb (Analyze_Abstract_Subprogram_Declaration): Remove
	redundant call to Is_Overriding_Operation.
	(Verify_Overriding_Indicator): Replace several occurrences of test on
	Is_Overriding_Operation by test on the presence of attribute
	Overridden_Operation.
	(Check_Convention): Replace test on Is_Overriding_Operation by test on
	the presence of Overridden_Operation.
	(Check_Overriding_Indicator): Add missing decoration of attribute
	Overridden_Operation. Minor code cleanup.
	(New_Overloaded_Entity): Replace occurrence of test on
	Is_Overriding_Operation by test on the presence of attribute
	Overridden_Operation. Remove redundant setting of attribute
	Is_Overriding_Operation plus minor code reorganization.
	Add missing decoration of attribute Overridden_Operation.
	* sem_elim.adb (Set_Eliminated): Replace test on
	Is_Overriding_Operation by test on the presence of Overridden_Operation.
	* sem_ch8.adb (Analyze_Subprogram_Renaming): Replace test on
	Is_Overriding_Operation by test on the presence of
	Overridden_Operation. Remove a redundant test on attribute
	Is_Overriding_Operation. 
	* lib-xref.adb (Generate_Reference): Replace test on
	Is_Overriding_Operation by test on the presence of Overridden_Operation.
	(Output_References): Replace test on Is_Overriding_Operation by test on
	the presence of Overridden_Operation.
	* sem_disp.adb (Override_Dispatching_Operation): Replace test on
	Is_Overriding_Operation by test on the presence of Overridden_Operation.
	Add missing decoration of attribute Overridden_Operation.

2010-10-26  Robert Dewar  <dewar@adacore.com>

	* sem_ch13.adb (Adjust_Record_For_Reverse_Bit_Order): Properly check
	RM 13.4.1(10).

2010-10-26  Bob Duff  <duff@adacore.com>

	* sem_res.adb (Resolve_Actuals): In case of certain
	internally-generated type conversions (created by OK_Convert_To, so the
	Conversion_OK flag is set), avoid fetching the component type when it's
	not really an array type, but a private type completed by an array type.

From-SVN: r165945

14 files changed, 187 insertions, 141 deletions

diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index c4ab243..b979f65 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,58 @@
+2010-10-26  Javier Miranda  <miranda@adacore.com>
+
+	* einfo.ads, einfo.adb (Is_Overriding_Operation): Removed.
+	(Set_Is_Overriding_Operation): Removed.
+	* sem_ch3.adb (Check_Abstract_Overriding): Remove redundant call to
+	Is_Overriding_Operation.
+	* exp_ch7.adb (Check_Visibly_Controlled): Remove redundant call to
+	Is_Overriding_Operation.
+	* sem_ch7.adb (Declare_Inherited_Private_Subprograms): Remove redundant
+	call to Set_Is_Overriding_Operation.
+	* sem_util.adb (Collect_Primitive_Operations): Replace test on
+	Is_Overriding_Operation by test on the presence of attribute
+	Overridden_Operation.
+	(Original_Corresponding_Operation): Remove redundant call to attribute
+	Is_Overriding_Operation.
+	* sem_ch6.adb (Analyze_Abstract_Subprogram_Declaration): Remove
+	redundant call to Is_Overriding_Operation.
+	(Verify_Overriding_Indicator): Replace several occurrences of test on
+	Is_Overriding_Operation by test on the presence of attribute
+	Overridden_Operation.
+	(Check_Convention): Replace test on Is_Overriding_Operation by test on
+	the presence of Overridden_Operation.
+	(Check_Overriding_Indicator): Add missing decoration of attribute
+	Overridden_Operation. Minor code cleanup.
+	(New_Overloaded_Entity): Replace occurrence of test on
+	Is_Overriding_Operation by test on the presence of attribute
+	Overridden_Operation. Remove redundant setting of attribute
+	Is_Overriding_Operation plus minor code reorganization.
+	Add missing decoration of attribute Overridden_Operation.
+	* sem_elim.adb (Set_Eliminated): Replace test on
+	Is_Overriding_Operation by test on the presence of Overridden_Operation.
+	* sem_ch8.adb (Analyze_Subprogram_Renaming): Replace test on
+	Is_Overriding_Operation by test on the presence of
+	Overridden_Operation. Remove a redundant test on attribute
+	Is_Overriding_Operation. 
+	* lib-xref.adb (Generate_Reference): Replace test on
+	Is_Overriding_Operation by test on the presence of Overridden_Operation.
+	(Output_References): Replace test on Is_Overriding_Operation by test on
+	the presence of Overridden_Operation.
+	* sem_disp.adb (Override_Dispatching_Operation): Replace test on
+	Is_Overriding_Operation by test on the presence of Overridden_Operation.
+	Add missing decoration of attribute Overridden_Operation.
+
+2010-10-26  Robert Dewar  <dewar@adacore.com>
+
+	* sem_ch13.adb (Adjust_Record_For_Reverse_Bit_Order): Properly check
+	RM 13.4.1(10).
+
+2010-10-26  Bob Duff  <duff@adacore.com>
+
+	* sem_res.adb (Resolve_Actuals): In case of certain
+	internally-generated type conversions (created by OK_Convert_To, so the
+	Conversion_OK flag is set), avoid fetching the component type when it's
+	not really an array type, but a private type completed by an array type.
+
 2010-10-26  Ed Schonberg  <schonberg@adacore.com>
 
 	* sem_ch5.adb: Adjust format of error message.
diff --git a/gcc/ada/einfo.adb b/gcc/ada/einfo.adb
index 4c2530a..e7f0b4f 100644
--- a/gcc/ada/einfo.adb
+++ b/gcc/ada/einfo.adb
@@ -283,7 +283,6 @@ package body Einfo is
    --    Referenced_As_LHS               Flag36
    --    Is_Known_Non_Null               Flag37
    --    Can_Never_Be_Null               Flag38
-   --    Is_Overriding_Operation         Flag39
    --    Body_Needed_For_SAL             Flag40
 
    --    Treat_As_Volatile               Flag41
@@ -515,6 +514,7 @@ package body Einfo is
    --    Has_Inheritable_Invariants      Flag248
    --    Has_Predicates                  Flag250
 
+   --    (unused)                        Flag39
    --    (unused)                        Flag151
    --    (unused)                        Flag249
    --    (unused)                        Flag251
@@ -1938,12 +1938,6 @@ package body Einfo is
       return Flag134 (Id);
    end Is_Optional_Parameter;
 
-   function Is_Overriding_Operation (Id : E) return B is
-   begin
-      pragma Assert (Is_Subprogram (Id));
-      return Flag39 (Id);
-   end Is_Overriding_Operation;
-
    function Is_Package_Body_Entity (Id : E) return B is
    begin
       return Flag160 (Id);
@@ -4418,12 +4412,6 @@ package body Einfo is
       Set_Flag134 (Id, V);
    end Set_Is_Optional_Parameter;
 
-   procedure Set_Is_Overriding_Operation (Id : E; V : B := True) is
-   begin
-      pragma Assert (Is_Subprogram (Id));
-      Set_Flag39 (Id, V);
-   end Set_Is_Overriding_Operation;
-
    procedure Set_Is_Package_Body_Entity (Id : E; V : B := True) is
    begin
       Set_Flag160 (Id, V);
@@ -7454,7 +7442,6 @@ package body Einfo is
       W ("Is_Obsolescent",                  Flag153 (Id));
       W ("Is_Only_Out_Parameter",           Flag226 (Id));
       W ("Is_Optional_Parameter",           Flag134 (Id));
-      W ("Is_Overriding_Operation",         Flag39  (Id));
       W ("Is_Package_Body_Entity",          Flag160 (Id));
       W ("Is_Packed",                       Flag51  (Id));
       W ("Is_Packed_Array_Type",            Flag138 (Id));
diff --git a/gcc/ada/einfo.ads b/gcc/ada/einfo.ads
index 3a0b36a..026c1b2 100644
--- a/gcc/ada/einfo.ads
+++ b/gcc/ada/einfo.ads
@@ -2484,10 +2484,6 @@ package Einfo is
 --       Applies to all entities, true for ordinary fixed point types and
 --       subtypes.
 
---    Is_Overriding_Operation (Flag39)
---       Present in subprograms. Set if the subprogram is a primitive
---       operation of a derived type, that overrides an inherited operation.
-
 --    Is_Package_Or_Generic_Package (synthesized)
 --       Applies to all entities. True for packages and generic packages.
 --       False for all other entities.
@@ -5167,7 +5163,6 @@ package Einfo is
    --    Is_Instantiated                     (Flag126)  (generic case only)
    --    Is_Intrinsic_Subprogram             (Flag64)
    --    Is_Machine_Code_Subprogram          (Flag137)  (non-generic case only)
-   --    Is_Overriding_Operation             (Flag39)   (non-generic case only)
    --    Is_Primitive                        (Flag218)
    --    Is_Primitive_Wrapper                (Flag195)  (non-generic case only)
    --    Is_Private_Descendant               (Flag53)
@@ -5287,13 +5282,13 @@ package Einfo is
    --    First_Entity                        (Node17)
    --    Alias                               (Node18)
    --    Last_Entity                         (Node20)
+   --    Overridden_Operation                (Node26)
    --    Subprograms_For_Type                (Node29)
    --    Has_Invariants                      (Flag232)
    --    Has_Postconditions                  (Flag240)
    --    Is_Machine_Code_Subprogram          (Flag137)
    --    Is_Pure                             (Flag44)
    --    Is_Intrinsic_Subprogram             (Flag64)
-   --    Is_Overriding_Operation             (Flag39)
    --    Is_Primitive                        (Flag218)
    --    Is_Thunk                            (Flag225)
    --    Default_Expressions_Processed       (Flag108)
@@ -5432,7 +5427,6 @@ package Einfo is
    --    Is_Intrinsic_Subprogram             (Flag64)
    --    Is_Machine_Code_Subprogram          (Flag137)  (non-generic case only)
    --    Is_Null_Init_Proc                   (Flag178)
-   --    Is_Overriding_Operation             (Flag39)   (non-generic case only)
    --    Is_Primitive                        (Flag218)
    --    Is_Primitive_Wrapper                (Flag195)  (non-generic case only)
    --    Is_Private_Descendant               (Flag53)
@@ -6314,7 +6308,6 @@ package Einfo is
    function Is_Object                           (Id : E) return B;
    function Is_Ordinary_Fixed_Point_Type        (Id : E) return B;
    function Is_Overloadable                     (Id : E) return B;
-   function Is_Overriding_Operation             (Id : E) return B;
    function Is_Private_Type                     (Id : E) return B;
    function Is_Protected_Type                   (Id : E) return B;
    function Is_Real_Type                        (Id : E) return B;
@@ -6705,7 +6698,6 @@ package Einfo is
    procedure Set_Is_Obsolescent                  (Id : E; V : B := True);
    procedure Set_Is_Only_Out_Parameter           (Id : E; V : B := True);
    procedure Set_Is_Optional_Parameter           (Id : E; V : B := True);
-   procedure Set_Is_Overriding_Operation         (Id : E; V : B := True);
    procedure Set_Is_Package_Body_Entity          (Id : E; V : B := True);
    procedure Set_Is_Packed                       (Id : E; V : B := True);
    procedure Set_Is_Packed_Array_Type            (Id : E; V : B := True);
@@ -7428,7 +7420,6 @@ package Einfo is
    pragma Inline (Is_Package_Body_Entity);
    pragma Inline (Is_Ordinary_Fixed_Point_Type);
    pragma Inline (Is_Overloadable);
-   pragma Inline (Is_Overriding_Operation);
    pragma Inline (Is_Packed);
    pragma Inline (Is_Packed_Array_Type);
    pragma Inline (Is_Potentially_Use_Visible);
@@ -7832,7 +7823,6 @@ package Einfo is
    pragma Inline (Set_Is_Obsolescent);
    pragma Inline (Set_Is_Only_Out_Parameter);
    pragma Inline (Set_Is_Optional_Parameter);
-   pragma Inline (Set_Is_Overriding_Operation);
    pragma Inline (Set_Is_Package_Body_Entity);
    pragma Inline (Set_Is_Packed);
    pragma Inline (Set_Is_Packed_Array_Type);
diff --git a/gcc/ada/exp_ch7.adb b/gcc/ada/exp_ch7.adb
index ac5ad0f..c590293 100644
--- a/gcc/ada/exp_ch7.adb
+++ b/gcc/ada/exp_ch7.adb
@@ -832,7 +832,7 @@ package body Exp_Ch7 is
    begin
       if Is_Derived_Type (Typ)
         and then Comes_From_Source (E)
-        and then not Is_Overriding_Operation (E)
+        and then not Present (Overridden_Operation (E))
       then
          --  We know that the explicit operation on the type does not override
          --  the inherited operation of the parent, and that the derivation
diff --git a/gcc/ada/lib-xref.adb b/gcc/ada/lib-xref.adb
index dbfbe45..b055304 100644
--- a/gcc/ada/lib-xref.adb
+++ b/gcc/ada/lib-xref.adb
@@ -847,7 +847,7 @@ package body Lib.Xref is
 
          if Typ = 'p'
            and then Is_Subprogram (N)
-           and then Is_Overriding_Operation (N)
+           and then Present (Overridden_Operation (N))
          then
             Xrefs.Table (Indx).Typ := 'P';
          else
@@ -2183,7 +2183,7 @@ package body Lib.Xref is
                      --  on operation that was overridden.
 
                      if Is_Subprogram (XE.Ent)
-                       and then Is_Overriding_Operation (XE.Ent)
+                       and then Present (Overridden_Operation (XE.Ent))
                      then
                         Output_Overridden_Op (Overridden_Operation (XE.Ent));
                      end if;
diff --git a/gcc/ada/sem_ch13.adb b/gcc/ada/sem_ch13.adb
index a46ba87..488a4d7 100644
--- a/gcc/ada/sem_ch13.adb
+++ b/gcc/ada/sem_ch13.adb
@@ -390,62 +390,69 @@ package body Sem_Ch13 is
                   declare
                      Fbit : constant Uint :=
                               Static_Integer (First_Bit (CC));
+                     Lbit : constant Uint :=
+                              Static_Integer (Last_Bit (CC));
 
                   begin
-                     --  Case of component with size > max machine scalar
+                     --  Case of component with last bit >= max machine scalar
 
-                     if Esize (Comp) > Max_Machine_Scalar_Size then
+                     if Lbit >= Max_Machine_Scalar_Size then
 
-                        --  Must begin on byte boundary
+                        --  This is allowed only if first bit is zero, and
+                        --  last bit + 1 is a multiple of storage unit size.
 
-                        if Fbit mod SSU /= 0 then
-                           Error_Msg_N
-                             ("illegal first bit value for "
-                              & "reverse bit order",
-                              First_Bit (CC));
-                           Error_Msg_Uint_1 := SSU;
-                           Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
+                        if Fbit = 0 and then (Lbit + 1) mod SSU = 0 then
 
-                           Error_Msg_N
-                             ("\must be a multiple of ^ "
-                              & "if size greater than ^",
-                              First_Bit (CC));
+                           --  This is the case to give a warning if enabled
 
-                           --  Must end on byte boundary
+                           if Warn_On_Reverse_Bit_Order then
+                              Error_Msg_N
+                                ("multi-byte field specified with "
+                                 & "  non-standard Bit_Order?", CC);
+
+                              if Bytes_Big_Endian then
+                                 Error_Msg_N
+                                   ("\bytes are not reversed "
+                                    & "(component is big-endian)?", CC);
+                              else
+                                 Error_Msg_N
+                                   ("\bytes are not reversed "
+                                    & "(component is little-endian)?", CC);
+                              end if;
+                           end if;
 
-                        elsif Esize (Comp) mod SSU /= 0 then
-                           Error_Msg_N
-                             ("illegal last bit value for "
-                              & "reverse bit order",
-                              Last_Bit (CC));
-                           Error_Msg_Uint_1 := SSU;
-                           Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
+                        --  Give error message for RM 13.4.1(10) violation
 
-                           Error_Msg_N
-                             ("\must be a multiple of ^ if size "
-                              & "greater than ^",
-                              Last_Bit (CC));
+                        else
+                           Error_Msg_FE
+                             ("machine scalar rules not followed for&",
+                              First_Bit (CC), Comp);
 
-                           --  OK, give warning if enabled
+                           Error_Msg_Uint_1 := Lbit;
+                           Error_Msg_Uint_2 := Max_Machine_Scalar_Size;
+                           Error_Msg_F
+                             ("\last bit (^) exceeds maximum machine "
+                              & "scalar size (^)",
+                              First_Bit (CC));
 
-                        elsif Warn_On_Reverse_Bit_Order then
-                           Error_Msg_N
-                             ("multi-byte field specified with "
-                              & "  non-standard Bit_Order?", CC);
+                           if (Lbit + 1) mod SSU /= 0 then
+                              Error_Msg_Uint_1 := SSU;
+                              Error_Msg_F
+                                ("\and is not a multiple of Storage_Unit (^) "
+                                 & "('R'M 13.4.1(10))",
+                                 First_Bit (CC));
 
-                           if Bytes_Big_Endian then
-                              Error_Msg_N
-                                ("\bytes are not reversed "
-                                 & "(component is big-endian)?", CC);
                            else
-                              Error_Msg_N
-                                ("\bytes are not reversed "
-                                 & "(component is little-endian)?", CC);
+                              Error_Msg_Uint_1 := Fbit;
+                              Error_Msg_F
+                                ("\and first bit (^) is non-zero "
+                                 & "('R'M 13.4.1(10))",
+                                 First_Bit (CC));
                            end if;
                         end if;
 
-                        --  Case where size is not greater than max machine
-                        --  scalar. For now, we just count these.
+                     --  OK case of machine scalar related component clause,
+                     --  For now, just count them.
 
                      else
                         Num_CC := Num_CC + 1;
@@ -509,17 +516,31 @@ package body Sem_Ch13 is
                --  Start of processing for Sort_CC
 
             begin
-               --  Collect the component clauses
+               --  Collect the machine scalar relevant component clauses
 
                Num_CC := 0;
                Comp   := First_Component_Or_Discriminant (R);
                while Present (Comp) loop
-                  if Present (Component_Clause (Comp))
-                    and then Esize (Comp) <= Max_Machine_Scalar_Size
-                  then
-                     Num_CC := Num_CC + 1;
-                     Comps (Num_CC) := Comp;
-                  end if;
+                  declare
+                     CC   : constant Node_Id := Component_Clause (Comp);
+
+                  begin
+                     --  Collect only component clauses whose last bit is less
+                     --  than machine scalar size. Any component clause whose
+                     --  last bit exceeds this value does not take part in
+                     --  machine scalar layout considerations. The test for
+                     --  Error_Posted makes sure we exclude component clauses
+                     --  for which we already posted an error.
+
+                     if Present (CC)
+                       and then not Error_Posted (Last_Bit (CC))
+                       and then Static_Integer (Last_Bit (CC)) <
+                                Max_Machine_Scalar_Size
+                     then
+                        Num_CC := Num_CC + 1;
+                        Comps (Num_CC) := Comp;
+                     end if;
+                  end;
 
                   Next_Component_Or_Discriminant (Comp);
                end loop;
diff --git a/gcc/ada/sem_ch3.adb b/gcc/ada/sem_ch3.adb
index 8bdd678..76d60a4 100644
--- a/gcc/ada/sem_ch3.adb
+++ b/gcc/ada/sem_ch3.adb
@@ -8895,7 +8895,6 @@ package body Sem_Ch3 is
          --  primitive marked with pragma Implemented.
 
          if Ada_Version >= Ada_2012
-           and then Is_Overriding_Operation (Subp)
            and then Present (Overridden_Operation (Subp))
            and then Has_Rep_Pragma
                       (Overridden_Operation (Subp), Name_Implemented)
diff --git a/gcc/ada/sem_ch6.adb b/gcc/ada/sem_ch6.adb
index 95ca6e4..920706b 100644
--- a/gcc/ada/sem_ch6.adb
+++ b/gcc/ada/sem_ch6.adb
@@ -374,7 +374,7 @@ package body Sem_Ch6 is
 
       elsif Warn_On_Redundant_Constructs
         and then not Is_Dispatching_Operation (Designator)
-        and then not Is_Overriding_Operation (Designator)
+        and then not Present (Overridden_Operation (Designator))
         and then (not Is_Operator_Symbol_Name (Chars (Designator))
                    or else Scop /= Scope (Etype (First_Formal (Designator))))
       then
@@ -1960,13 +1960,13 @@ package body Sem_Ch6 is
             then
                null;
 
-            elsif not Is_Overriding_Operation (Spec_Id) then
+            elsif not Present (Overridden_Operation (Spec_Id)) then
                Error_Msg_NE
                  ("subprogram& is not overriding", Body_Spec, Spec_Id);
             end if;
 
          elsif Must_Not_Override (Body_Spec) then
-            if Is_Overriding_Operation (Spec_Id) then
+            if Present (Overridden_Operation (Spec_Id)) then
                Error_Msg_NE
                  ("subprogram& overrides inherited operation",
                   Body_Spec, Spec_Id);
@@ -1991,7 +1991,7 @@ package body Sem_Ch6 is
             end if;
 
          elsif Style_Check --  ??? incorrect use of Style_Check!
-           and then Is_Overriding_Operation (Spec_Id)
+           and then Present (Overridden_Operation (Spec_Id))
          then
             pragma Assert (Unit_Declaration_Node (Body_Id) = N);
             Style.Missing_Overriding (N, Body_Id);
@@ -4196,7 +4196,7 @@ package body Sem_Ch6 is
                   Error_Msg_Sloc   := Sloc (Op);
 
                   if Comes_From_Source (Op) or else No (Alias (Op)) then
-                     if not Is_Overriding_Operation (Op) then
+                     if not Present (Overridden_Operation (Op)) then
                         Error_Msg_N ("\\primitive % defined #", Typ);
                      else
                         Error_Msg_N
@@ -4672,7 +4672,7 @@ package body Sem_Ch6 is
             end if;
 
          elsif Is_Subprogram (Subp) then
-            Set_Is_Overriding_Operation (Subp);
+            Set_Overridden_Operation (Subp, Overridden_Subp);
          end if;
 
          --  If primitive flag is set or this is a protected operation, then
@@ -4728,10 +4728,9 @@ package body Sem_Ch6 is
                end if;
 
             elsif Must_Override (Spec) then
-               if Is_Overriding_Operation (Subp) then
-                  null;
-
-               elsif not Can_Override then
+               if No (Overridden_Operation (Subp))
+                 and then not Can_Override
+               then
                   Error_Msg_NE ("subprogram & is not overriding", Spec, Subp);
                end if;
 
@@ -4742,8 +4741,6 @@ package body Sem_Ch6 is
                 not Is_Predefined_File_Name
                       (Unit_File_Name (Get_Source_Unit (Subp)))
             then
-               Set_Is_Overriding_Operation (Subp);
-
                --  If style checks are enabled, indicate that the indicator is
                --  missing. However, at the point of declaration, the type of
                --  which this is a primitive operation may be private, in which
@@ -7860,7 +7857,7 @@ package body Sem_Ch6 is
             if Ada_Version >= Ada_2012
               and then No (Overridden_Subp)
               and then Is_Dispatching_Operation (S)
-              and then Is_Overriding_Operation (S)
+              and then Present (Overridden_Operation (S))
             then
                Overridden_Subp := Overridden_Operation (S);
             end if;
@@ -7982,22 +7979,18 @@ package body Sem_Ch6 is
                      Check_Operation_From_Private_View (S, E);
                   end if;
 
-                  --  In any case the implicit operation remains hidden by
-                  --  the existing declaration, which is overriding.
+                  --  In any case the implicit operation remains hidden by the
+                  --  existing declaration, which is overriding. Indicate that
+                  --  E overrides the operation from which S is inherited.
 
-                  Set_Is_Overriding_Operation (E);
+                  if Present (Alias (S)) then
+                     Set_Overridden_Operation (E, Alias (S));
+                  else
+                     Set_Overridden_Operation (E, S);
+                  end if;
 
                   if Comes_From_Source (E) then
                      Check_Overriding_Indicator (E, S, Is_Primitive => False);
-
-                     --  Indicate that E overrides the operation from which
-                     --  S is inherited.
-
-                     if Present (Alias (S)) then
-                        Set_Overridden_Operation (E, Alias (S));
-                     else
-                        Set_Overridden_Operation (E, S);
-                     end if;
                   end if;
 
                   return;
@@ -8145,22 +8138,17 @@ package body Sem_Ch6 is
                            if No (Next_Entity (Prev)) then
                               Set_Last_Entity (Current_Scope, Prev);
                            end if;
-
                         end if;
                      end if;
 
                      Enter_Overloaded_Entity (S);
-                     Set_Is_Overriding_Operation (S);
+                     Set_Overridden_Operation (S, E);
                      Check_Overriding_Indicator (S, E, Is_Primitive => True);
 
                      --  If S is a user-defined subprogram or a null procedure
                      --  expanded to override an inherited null procedure, or a
                      --  predefined dispatching primitive then indicate that E
-                     --  overrides the operation from which S is inherited. It
-                     --  seems odd that Overridden_Operation isn't set in all
-                     --  cases where Is_Overriding_Operation is true, but doing
-                     --  so causes infinite loops in the compiler for implicit
-                     --  overriding subprograms. ???
+                     --  overrides the operation from which S is inherited.
 
                      if Comes_From_Source (S)
                        or else
@@ -8176,8 +8164,6 @@ package body Sem_Ch6 is
                      then
                         if Present (Alias (E)) then
                            Set_Overridden_Operation (S, Alias (E));
-                        else
-                           Set_Overridden_Operation (S, E);
                         end if;
                      end if;
 
diff --git a/gcc/ada/sem_ch7.adb b/gcc/ada/sem_ch7.adb
index 9b72558..ce6184f 100644
--- a/gcc/ada/sem_ch7.adb
+++ b/gcc/ada/sem_ch7.adb
@@ -1537,7 +1537,6 @@ package body Sem_Ch7 is
                            New_Op := Node (Op_Elmt_2);
                            Replace_Elmt (Op_Elmt, New_Op);
                            Remove_Elmt  (Op_List, Op_Elmt_2);
-                           Set_Is_Overriding_Operation (New_Op);
                            Set_Overridden_Operation (New_Op, Parent_Subp);
 
                            --  We don't need to inherit its dispatching slot.
diff --git a/gcc/ada/sem_ch8.adb b/gcc/ada/sem_ch8.adb
index 9785348..0fbd49a 100644
--- a/gcc/ada/sem_ch8.adb
+++ b/gcc/ada/sem_ch8.adb
@@ -1968,7 +1968,7 @@ package body Sem_Ch8 is
 
          --  Ada 2005: check overriding indicator
 
-         if Is_Overriding_Operation (Rename_Spec) then
+         if Present (Overridden_Operation (Rename_Spec)) then
             if Must_Not_Override (Specification (N)) then
                Error_Msg_NE
                  ("subprogram& overrides inherited operation",
@@ -2110,7 +2110,7 @@ package body Sem_Ch8 is
            and then No (DTC_Entity (Old_S))
            and then Present (Alias (Old_S))
            and then not Is_Abstract_Subprogram (Alias (Old_S))
-           and then Is_Overriding_Operation (Alias (Old_S))
+           and then Present (Overridden_Operation (Alias (Old_S)))
          then
             Old_S := Alias (Old_S);
          end if;
diff --git a/gcc/ada/sem_disp.adb b/gcc/ada/sem_disp.adb
index 774c2af..9312192 100644
--- a/gcc/ada/sem_disp.adb
+++ b/gcc/ada/sem_disp.adb
@@ -889,7 +889,7 @@ package body Sem_Disp is
          --     New_Stream_Subprogram)
 
          if Present (Old_Subp)
-           and then Is_Overriding_Operation (Subp)
+           and then Present (Overridden_Operation (Subp))
            and then Is_Dispatching_Operation (Old_Subp)
          then
             pragma Assert
@@ -1117,7 +1117,7 @@ package body Sem_Disp is
            and then Is_Controlled (Tagged_Type)
            and then not Is_Visibly_Controlled (Tagged_Type)
          then
-            Set_Is_Overriding_Operation (Subp, False);
+            Set_Overridden_Operation (Subp, Empty);
 
             --  If the subprogram specification carries an overriding
             --  indicator, no need for the warning: it is either redundant,
@@ -1139,7 +1139,6 @@ package body Sem_Disp is
 
          else
             Override_Dispatching_Operation (Tagged_Type, Ovr_Subp, Subp);
-            Set_Is_Overriding_Operation (Subp);
 
             --  Ada 2005 (AI-251): In case of late overriding of a primitive
             --  that covers abstract interface subprograms we must register it
diff --git a/gcc/ada/sem_elim.adb b/gcc/ada/sem_elim.adb
index c160c8e..9f6374e 100644
--- a/gcc/ada/sem_elim.adb
+++ b/gcc/ada/sem_elim.adb
@@ -267,7 +267,7 @@ package body Sem_Elim is
                   --  If an overriding dispatching primitive is eliminated then
                   --  its parent must have been eliminated.
 
-                  if Is_Overriding_Operation (E)
+                  if Present (Overridden_Operation (E))
                     and then not Is_Eliminated (Overridden_Operation (E))
                   then
                      Error_Msg_Name_1 := Chars (E);
diff --git a/gcc/ada/sem_res.adb b/gcc/ada/sem_res.adb
index cf71046..784f6bd 100644
--- a/gcc/ada/sem_res.adb
+++ b/gcc/ada/sem_res.adb
@@ -3334,45 +3334,55 @@ package body Sem_Res is
                if Ekind (F) = E_In_Out_Parameter
                  and then Is_Array_Type (Etype (F))
                then
-                  if Has_Aliased_Components (Etype (Expression (A)))
-                    /= Has_Aliased_Components (Etype (F))
-                  then
-
-                     --  In a view conversion, the conversion must be legal in
-                     --  both directions, and thus both component types must be
-                     --  aliased, or neither (4.6 (8)).
+                  --  In a view conversion, the conversion must be legal in
+                  --  both directions, and thus both component types must be
+                  --  aliased, or neither (4.6 (8)).
 
-                     --  The additional rule 4.6 (24.9.2) seems unduly
-                     --  restrictive: the privacy requirement should not apply
-                     --  to generic types, and should be checked in an
-                     --  instance. ARG query is in order ???
+                  --  The extra rule in 4.6 (24.9.2) seems unduly restrictive:
+                  --  the privacy requirement should not apply to generic
+                  --  types, and should be checked in an instance. ARG query
+                  --  is in order ???
 
+                  if Has_Aliased_Components (Etype (Expression (A))) /=
+                     Has_Aliased_Components (Etype (F))
+                  then
                      Error_Msg_N
                        ("both component types in a view conversion must be"
                          & " aliased, or neither", A);
 
+                  --  Comment here??? what set of cases???
+
                   elsif
                      not Same_Ancestor (Etype (F), Etype (Expression (A)))
                   then
+                     --  Check view conv between unrelated by ref array types
+
                      if Is_By_Reference_Type (Etype (F))
                         or else Is_By_Reference_Type (Etype (Expression (A)))
                      then
                         Error_Msg_N
                           ("view conversion between unrelated by reference " &
                            "array types not allowed (\'A'I-00246)", A);
-                     else
+
+                     --  In Ada 2005 mode, check view conversion component
+                     --  type cannot be private, tagged, or volatile. Note
+                     --  that we only apply this to source conversions. The
+                     --  generated code can contain conversions which are
+                     --  not subject to this test, and we cannot extract the
+                     --  component type in such cases since it is not present.
+
+                     elsif Comes_From_Source (A)
+                       and then Ada_Version >= Ada_2005
+                     then
                         declare
                            Comp_Type : constant Entity_Id :=
                                          Component_Type
                                            (Etype (Expression (A)));
                         begin
-                           if Comes_From_Source (A)
-                             and then Ada_Version >= Ada_2005
-                             and then
-                               ((Is_Private_Type (Comp_Type)
-                                   and then not Is_Generic_Type (Comp_Type))
-                                 or else Is_Tagged_Type (Comp_Type)
-                                 or else Is_Volatile (Comp_Type))
+                           if (Is_Private_Type (Comp_Type)
+                                 and then not Is_Generic_Type (Comp_Type))
+                             or else Is_Tagged_Type (Comp_Type)
+                             or else Is_Volatile (Comp_Type)
                            then
                               Error_Msg_N
                                 ("component type of a view conversion cannot"
@@ -3385,8 +3395,10 @@ package body Sem_Res is
                   end if;
                end if;
 
+               --  Resolve expression if conversion is all OK
+
                if (Conversion_OK (A)
-                     or else Valid_Conversion (A, Etype (A), Expression (A)))
+                    or else Valid_Conversion (A, Etype (A), Expression (A)))
                  and then not Is_Ref_To_Bit_Packed_Array (Expression (A))
                then
                   Resolve (Expression (A));
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 58691c4..29826c0 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -1890,7 +1890,7 @@ package body Sem_Util is
                   if Chars (Id) = Name_Op_Eq
                     and then Is_Dispatching_Operation (Id)
                     and then Present (Alias (Id))
-                    and then Is_Overriding_Operation (Alias (Id))
+                    and then Present (Overridden_Operation (Alias (Id)))
                     and then Base_Type (Etype (First_Entity (Id))) =
                                Base_Type (Etype (First_Entity (Alias (Id))))
                   then
@@ -9957,9 +9957,7 @@ package body Sem_Util is
       --  If S overrides an inherted subprogram S2 the original corresponding
       --  operation of S is the original corresponding operation of S2
 
-      elsif Is_Overriding_Operation (S)
-        and then Present (Overridden_Operation (S))
-      then
+      elsif Present (Overridden_Operation (S)) then
          return Original_Corresponding_Operation (Overridden_Operation (S));
 
       --  otherwise it is S itself