[multiple changes]

2010-09-10  Robert Dewar  <dewar@adacore.com>

	* gnat_ugn.texi: Add documentation for -gnatw.s/S
	* sem_ch13.adb (Analyze_Attribute_Definition_Clause, case
	Component_Size): Implement warning on overriden size clause.
	(Analyze_Record_Representation_Clause): Implement warning on overriden
	size clause.
	* sem_warn.ads, sem_warn.adb (Warn_On_Overridden_Size): New flag
	(-gnatw.s/S).
	* ug_words: Add entries for -gnatw.s/S.
	* vms_data.ads, usage.adb: Add line for -gnatw.s/-gnatw.S.
	* gcc-interface/Make-lang.in: Update dependencies.

2010-09-10  Vincent Celier  <celier@adacore.com>

	* prj-dect.adb (Parse_Package_Declaration): Allow a package to extend
	a package with the same name from an imported or extended project.
	* prj-proc.adb (Process_Declarative_Items): Process package extensions

2010-09-10  Bob Duff  <duff@adacore.com>

	* exp_ch6.adb (Expand_Call): Do not perform a null_exclusion check on
	'out' parameters.

From-SVN: r164194

gcc/ada/ChangeLog

 2010-09-10  Robert Dewar  <dewar@adacore.com>
 
+	* gnat_ugn.texi: Add documentation for -gnatw.s/S
+	* sem_ch13.adb (Analyze_Attribute_Definition_Clause, case
+	Component_Size): Implement warning on overriden size clause.
+	(Analyze_Record_Representation_Clause): Implement warning on overriden
+	size clause.
+	* sem_warn.ads, sem_warn.adb (Warn_On_Overridden_Size): New flag
+	(-gnatw.s/S).
+	* ug_words: Add entries for -gnatw.s/S.
+	* vms_data.ads, usage.adb: Add line for -gnatw.s/-gnatw.S.
+	* gcc-interface/Make-lang.in: Update dependencies.
+
+2010-09-10  Vincent Celier  <celier@adacore.com>
+
+	* prj-dect.adb (Parse_Package_Declaration): Allow a package to extend
+	a package with the same name from an imported or extended project.
+	* prj-proc.adb (Process_Declarative_Items): Process package extensions
+
+2010-09-10  Bob Duff  <duff@adacore.com>
+
+	* exp_ch6.adb (Expand_Call): Do not perform a null_exclusion check on
+	'out' parameters.
+
+2010-09-10  Robert Dewar  <dewar@adacore.com>
+
 	* sem.adb: Minor reformatting.
 
 2010-09-10  Bob Duff  <duff@adacore.com>

gcc/ada/exp_ch6.adb

@@ -2330,17 +2330,22 @@ package body Exp_Ch6 is
          end if;
 
          --  Perform the check of 4.6(49) that prevents a null value from being
-         --  passed as an actual to an access parameter. Note that the check is
-         --  elided in the common cases of passing an access attribute or
+         --  passed as an actual to an access parameter. Note that the check
+         --  is elided in the common cases of passing an access attribute or
          --  access parameter as an actual. Also, we currently don't enforce
          --  this check for expander-generated actuals and when -gnatdj is set.
 
          if Ada_Version >= Ada_05 then
 
-            --  Ada 2005 (AI-231): Check null-excluding access types
+            --  Ada 2005 (AI-231): Check null-excluding access types. Note that
+            --  the intent of 6.4.1(13) is that null-exclusion checks should
+            --  not be done for 'out' parameters, even though it refers only
+            --  to constraint checks, and a null_exlusion is not a constraint.
+            --  Note that AI05-0196-1 corrects this mistake in the RM.
 
             if Is_Access_Type (Etype (Formal))
               and then Can_Never_Be_Null (Etype (Formal))
+              and then Ekind (Formal) /= E_Out_Parameter
               and then Nkind (Prev) /= N_Raise_Constraint_Error
               and then (Known_Null (Prev)
                           or else not Can_Never_Be_Null (Etype (Prev)))
@@ -2424,10 +2429,10 @@ package body Exp_Ch6 is
          --  since this is a left side reference. We only do this for calls
          --  from the source program since we assume that compiler generated
          --  calls explicitly generate any required checks. We also need it
-         --  only if we are doing standard validity checks, since clearly it
-         --  is not needed if validity checks are off, and in subscript
-         --  validity checking mode, all indexed components are checked with
-         --  a call directly from Expand_N_Indexed_Component.
+         --  only if we are doing standard validity checks, since clearly it is
+         --  not needed if validity checks are off, and in subscript validity
+         --  checking mode, all indexed components are checked with a call
+         --  directly from Expand_N_Indexed_Component.
 
          if Comes_From_Source (N)
            and then Ekind (Formal) /= E_In_Parameter
@@ -2593,11 +2598,11 @@ package body Exp_Ch6 is
 
       --  Deals with Dispatch_Call if we still have a call, before expanding
       --  extra actuals since this will be done on the re-analysis of the
-      --  dispatching call. Note that we do not try to shorten the actual
-      --  list for a dispatching call, it would not make sense to do so.
-      --  Expansion of dispatching calls is suppressed when VM_Target, because
-      --  the VM back-ends directly handle the generation of dispatching
-      --  calls and would have to undo any expansion to an indirect call.
+      --  dispatching call. Note that we do not try to shorten the actual list
+      --  for a dispatching call, it would not make sense to do so. Expansion
+      --  of dispatching calls is suppressed when VM_Target, because the VM
+      --  back-ends directly handle the generation of dispatching calls and
+      --  would have to undo any expansion to an indirect call.
 
       if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement)
         and then Present (Controlling_Argument (N))
@@ -2605,8 +2610,8 @@ package body Exp_Ch6 is
          if Tagged_Type_Expansion then
             Expand_Dispatching_Call (N);
 
-            --  The following return is worrisome. Is it really OK to
-            --  skip all remaining processing in this procedure ???
+            --  The following return is worrisome. Is it really OK to skip all
+            --  remaining processing in this procedure ???
 
             return;
 
@@ -2624,8 +2629,8 @@ package body Exp_Ch6 is
 
       --  Similarly, expand calls to RCI subprograms on which pragma
       --  All_Calls_Remote applies. The rewriting will be reanalyzed
-      --  later. Do this only when the call comes from source since we do
-      --  not want such a rewriting to occur in expanded code.
+      --  later. Do this only when the call comes from source since we
+      --  do not want such a rewriting to occur in expanded code.
 
       if Is_All_Remote_Call (N) then
          Expand_All_Calls_Remote_Subprogram_Call (N);
@@ -2650,15 +2655,15 @@ package body Exp_Ch6 is
          end loop;
       end if;
 
-      --  At this point we have all the actuals, so this is the point at
-      --  which the various expansion activities for actuals is carried out.
+      --  At this point we have all the actuals, so this is the point at which
+      --  the various expansion activities for actuals is carried out.
 
       Expand_Actuals (N, Subp);
 
-      --  If the subprogram is a renaming, or if it is inherited, replace it
-      --  in the call with the name of the actual subprogram being called.
-      --  If this is a dispatching call, the run-time decides what to call.
-      --  The Alias attribute does not apply to entries.
+      --  If the subprogram is a renaming, or if it is inherited, replace it in
+      --  the call with the name of the actual subprogram being called. If this
+      --  is a dispatching call, the run-time decides what to call. The Alias
+      --  attribute does not apply to entries.
 
       if Nkind (N) /= N_Entry_Call_Statement
         and then No (Controlling_Argument (N))
@@ -2827,10 +2832,10 @@ package body Exp_Ch6 is
          if Is_Access_Protected_Subprogram_Type
               (Base_Type (Etype (Prefix (Name (N)))))
          then
-            --  If this is a call through an access to protected operation,
-            --  the prefix has the form (object'address, operation'access).
-            --  Rewrite as a for other protected calls: the object is the
-            --  first parameter of the list of actuals.
+            --  If this is a call through an access to protected operation, the
+            --  prefix has the form (object'address, operation'access). Rewrite
+            --  as a for other protected calls: the object is the 1st parameter
+            --  of the list of actuals.
 
             declare
                Call : Node_Id;
@@ -2905,11 +2910,11 @@ package body Exp_Ch6 is
 
       --  In the case where the intrinsic is to be processed by the back end,
       --  the call to Expand_Intrinsic_Call will do nothing, which is fine,
-      --  since the idea in this case is to pass the call unchanged.
-      --  If the intrinsic is an inherited unchecked conversion, and the
-      --  derived type is the target type of the conversion, we must retain
-      --  it as the return type of the expression. Otherwise the expansion
-      --  below, which uses the parent operation, will yield the wrong type.
+      --  since the idea in this case is to pass the call unchanged. If the
+      --  intrinsic is an inherited unchecked conversion, and the derived type
+      --  is the target type of the conversion, we must retain it as the return
+      --  type of the expression. Otherwise the expansion below, which uses the
+      --  parent operation, will yield the wrong type.
 
       if Is_Intrinsic_Subprogram (Subp) then
          Expand_Intrinsic_Call (N, Subp);

gcc/ada/gnat_ugn.texi

@@ -5582,6 +5582,25 @@ To suppress these back end warnings as well, use the switch @option{-w}
 in addition to @option{-gnatws}. Also this switch has no effect on the
 handling of style check messages.
 
+@item -gnatw.s
+@emph{Activate warnings on overridden size clauses.}
+@cindex @option{-gnatw.s} (@command{gcc})
+@cindex Record Representation (component sizes)
+This switch activates warnings on component clauses in record
+representation clauses where the length given overrides that
+specified by an explicit size clause for the component type. A
+warning is similarly given in the array case if a specified
+component size overrides an explicit size clause for the array
+component type.
+Note that @option{-gnatwa} does not affect the setting of this warning option.
+
+@item -gnatw.S
+@emph{Suppress warnings on overriddebn size clauses.}
+@cindex @option{-gnatw.S} (@command{gcc})
+This switch suppresses warnings on component clauses in record
+representation clauses that override size clauses, and similar
+warnings when an array component size overrides a size clause.
+
 @item -gnatwt
 @emph{Activate warnings for tracking of deleted conditional code.}
 @cindex @option{-gnatwt} (@command{gcc})

gcc/ada/prj-dect.adb

@@ -1027,8 +1027,9 @@ package body Prj.Dect is
       First_Attribute        : Attribute_Node_Id := Empty_Attribute;
       Current_Package        : Package_Node_Id   := Empty_Package;
       First_Declarative_Item : Project_Node_Id   := Empty_Node;
-
       Package_Location       : constant Source_Ptr := Token_Ptr;
+      Renaming               : Boolean := False;
+      Extending              : Boolean := False;
 
    begin
       Package_Declaration :=
@@ -1149,13 +1150,20 @@ package body Prj.Dect is
       end if;
 
       if Token = Tok_Renames then
+         Renaming := True;
+      elsif Token = Tok_Extends then
+         Extending := True;
+      end if;
+
+      if Renaming or else Extending then
          if Is_Config_File then
             Error_Msg
               (Flags,
-               "no package renames in configuration projects", Token_Ptr);
+               "no package rename or extension in configuration projects",
+               Token_Ptr);
          end if;
 
-         --  Scan past "renames"
+         --  Scan past "renames" or "extends"
 
          Scan (In_Tree);
 
@@ -1249,7 +1257,9 @@ package body Prj.Dect is
                end if;
             end if;
          end if;
+      end if;
 
+      if Renaming then
          Expect (Tok_Semicolon, "`;`");
          Set_End_Of_Line (Package_Declaration);
          Set_Previous_Line_Node (Package_Declaration);
@@ -1305,7 +1315,7 @@ package body Prj.Dect is
          Remove_Next_End_Node;
 
       else
-         Error_Msg (Flags, "expected IS or RENAMES", Token_Ptr);
+         Error_Msg (Flags, "expected IS", Token_Ptr);
       end if;
 
    end Parse_Package_Declaration;

gcc/ada/prj-proc.adb

@@ -1428,7 +1428,7 @@ package body Prj.Proc is
 
                      if Present (Project_Of_Renamed_Package) then
 
-                        --  Renamed package
+                        --  Renamed or extending package
 
                         declare
                            Project_Name : constant Name_Id :=
@@ -1466,8 +1466,6 @@ package body Prj.Proc is
                               In_Tree    => In_Tree);
                         end;
 
-                     --  Standard package declaration, not renaming
-
                      else
                         --  Set the default values of the attributes
 
@@ -1482,19 +1480,22 @@ package body Prj.Proc is
                                 (Current_Item, From_Project_Node_Tree)),
                            Project_Level => False);
 
-                        --  And process declarative items of the new package
-
-                        Process_Declarative_Items
-                          (Project                => Project,
-                           In_Tree                => In_Tree,
-                           Flags                  => Flags,
-                           From_Project_Node      => From_Project_Node,
-                           From_Project_Node_Tree => From_Project_Node_Tree,
-                           Pkg                    => New_Pkg,
-                           Item                   =>
-                             First_Declarative_Item_Of
-                               (Current_Item, From_Project_Node_Tree));
                      end if;
+
+                     --  Process declarative items (nothing to do when the
+                     --  package is renaming, as the first declarative item is
+                     --  null).
+
+                     Process_Declarative_Items
+                       (Project                => Project,
+                        In_Tree                => In_Tree,
+                        Flags                  => Flags,
+                        From_Project_Node      => From_Project_Node,
+                        From_Project_Node_Tree => From_Project_Node_Tree,
+                        Pkg                    => New_Pkg,
+                        Item                   =>
+                          First_Declarative_Item_Of
+                            (Current_Item, From_Project_Node_Tree));
                   end;
                end if;
 

gcc/ada/sem_ch13.adb

@@ -1283,6 +1283,7 @@ package body Sem_Ch13 is
 
          when Attribute_Component_Size => Component_Size_Case : declare
             Csize    : constant Uint := Static_Integer (Expr);
+            Ctyp     : Entity_Id;
             Btype    : Entity_Id;
             Biased   : Boolean;
             New_Ctyp : Entity_Id;
@@ -1295,13 +1296,14 @@ package body Sem_Ch13 is
             end if;
 
             Btype := Base_Type (U_Ent);
+            Ctyp := Component_Type (Btype);
 
             if Has_Component_Size_Clause (Btype) then
                Error_Msg_N
                  ("component size clause for& previously given", Nam);
 
             elsif Csize /= No_Uint then
-               Check_Size (Expr, Component_Type (Btype), Csize, Biased);
+               Check_Size (Expr, Ctyp, Csize, Biased);
 
                if Has_Aliased_Components (Btype)
                  and then Csize < 32
@@ -1367,6 +1369,17 @@ package body Sem_Ch13 is
                   end if;
                end if;
 
+               --  Deal with warning on overridden size
+
+               if Warn_On_Overridden_Size
+                 and then Has_Size_Clause (Ctyp)
+                 and then RM_Size (Ctyp) /= Csize
+               then
+                  Error_Msg_NE
+                    ("?component size overrides size clause for&",
+                     N, Ctyp);
+               end if;
+
                Set_Has_Component_Size_Clause (Btype, True);
                Set_Has_Non_Standard_Rep      (Btype, True);
             end if;
@@ -2749,6 +2762,15 @@ package body Sem_Ch13 is
                         Set_Normalized_First_Bit (Comp, Fbit mod SSU);
                         Set_Normalized_Position  (Comp, Fbit / SSU);
 
+                        if Warn_On_Overridden_Size
+                          and then Has_Size_Clause (Etype (Comp))
+                          and then RM_Size (Etype (Comp)) /= Esize (Comp)
+                        then
+                           Error_Msg_NE
+                             ("?component size overrides size clause for&",
+                              Component_Name (CC), Etype (Comp));
+                        end if;
+
                         --  This information is also set in the corresponding
                         --  component of the base type, found by accessing the
                         --  Original_Record_Component link if it is present.

gcc/ada/sem_warn.adb

@@ -3085,6 +3085,7 @@ package body Sem_Warn is
             Warn_On_Object_Renames_Function     := True;
             Warn_On_Obsolescent_Feature         := True;
             Warn_On_Overlap                     := True;
+            Warn_On_Overridden_Size             := True;
             Warn_On_Parameter_Order             := True;
             Warn_On_Questionable_Missing_Parens := True;
             Warn_On_Record_Holes                := True;
@@ -3135,6 +3136,12 @@ package body Sem_Warn is
          when 'R' =>
             Warn_On_Object_Renames_Function     := False;
 
+         when 's' =>
+            Warn_On_Overridden_Size             := True;
+
+         when 'S' =>
+            Warn_On_Overridden_Size             := False;
+
          when 'u' =>
             Warn_On_Unordered_Enumeration_Type  := True;
 
@@ -3268,6 +3275,7 @@ package body Sem_Warn is
             Warn_On_Object_Renames_Function     := False;
             Warn_On_Obsolescent_Feature         := False;
             Warn_On_Overlap                     := False;
+            Warn_On_Overridden_Size             := False;
             Warn_On_Parameter_Order             := False;
             Warn_On_Record_Holes                := False;
             Warn_On_Questionable_Missing_Parens := False;

gcc/ada/sem_warn.ads

@@ -47,6 +47,12 @@ package Sem_Warn is
    --  Warn when explicit record component clauses leave uncovered holes (gaps)
    --  in a record layout. Off by default, set by -gnatw.h (but not -gnatwa).
 
+   Warn_On_Overridden_Size : Boolean := False;
+   --  Warn when explicit record component clause or array component_size
+   --  clause specifies a size that overrides a size for the typen which was
+   --  set with an explicit size clause. Off by default, set by -gnatw.sn (but
+   --  not -gnatwa).
+
    ------------------------
    -- Warnings Off Table --
    ------------------------

gcc/ada/ug_words

@@ -161,6 +161,8 @@ gcc -c          ^ GNAT COMPILE
 -gnatwP         ^ /WARNINGS=NOINEFFECTIVE_INLINE
 -gnatw.p        ^ /WARNINGS=PARAMETER_ORDER
 -gnatw.P        ^ /WARNINGS=NO_PARAMETER_ORDER
+-gnatw.h        ^ /WARNINGS=OVERRIDING_SIZE
+-gnatw.H        ^ /WARNINGS=NOOVERRIDING_SIZE
 -gnatwq         ^ /WARNINGS=MISSING_PARENS
 -gnatwQ         ^ /WARNINGS=NOMISSING_PARENS
 -gnatwr         ^ /WARNINGS=REDUNDANT

gcc/ada/usage.adb

@@ -468,6 +468,8 @@ begin
    Write_Line ("        .r+  turn on warnings for object renaming function");
    Write_Line ("        .R*  turn off warnings for object renaming function");
    Write_Line ("        s    suppress all info/warnings");
+   Write_Line ("        .s   turn on warnings for overridden size clause");
+   Write_Line ("        .S*  turn off warnings for overridden size clause");
    Write_Line ("        t    turn on warnings for tracking deleted code");
    Write_Line ("        T*   turn off warnings for tracking deleted code");
    Write_Line ("        u+   turn on warnings for unused entity");

gcc/ada/vms_data.ads

@@ -3011,6 +3011,10 @@ package VMS_Data is
                                                "-gnatw.R "                 &
                                             "SUPPRESS "                    &
                                                "-gnatws "                  &
+                                            "OVERRIDING_SIZE "             &
+                                               "-gnatw.s "                 &
+                                            "NOOVERRIDING_SIZE "           &
+                                               "-gnatw.S "                 &
                                             "DELETED_CODE "                &
                                                "-gnatwt "                  &
                                             "NODELETED_CODE "              &