[multiple changes]

2011-08-05  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch12.adb (Analyze_Formal_Package_Declaration): reject a formal
	package whose name is the same as that of the generic unit, or its
	ultimate prefix.

2011-08-05  Bob Duff  <duff@adacore.com>

	* a-fihema.adb, a-fihema.ads: Minor comment improvements.
	* sem_ch3.adb, exp_ch5.adb, exp_ch7.adb, exp_ch7.ads, exp_util.adb:
	Minor comment fixes.

From-SVN: r177438

gcc/ada/ChangeLog

+2011-08-05  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_ch12.adb (Analyze_Formal_Package_Declaration): reject a formal
+	package whose name is the same as that of the generic unit, or its
+	ultimate prefix.
+
+2011-08-05  Bob Duff  <duff@adacore.com>
+
+	* a-fihema.adb, a-fihema.ads: Minor comment improvements.
+	* sem_ch3.adb, exp_ch5.adb, exp_ch7.adb, exp_ch7.ads, exp_util.adb:
+	Minor comment fixes.
+
 2011-08-05  Arnaud Charlet  <charlet@adacore.com>
 
 	* make.adb (Linking_Phase): No longer need to set source search path

gcc/ada/a-fihema.adb

@@ -43,8 +43,13 @@ with System.Storage_Pools;    use System.Storage_Pools;
 package body Ada.Finalization.Heap_Management is
 
    Header_Size   : constant Storage_Count  := Node'Size / Storage_Unit;
+   --  Size of the header in bytes. Added to Storage_Size requested by
+   --  Allocate/Deallocate to determine the Storage_Size passed to the
+   --  underlying pool.
+
    Header_Offset : constant Storage_Offset := Header_Size;
-   --  Comments needed???
+   --  Offset from the header to the actual object. Used to get from the
+   --  address of a header to the address of the actual object, and vice-versa.
 
    function Address_To_Node_Ptr is
      new Ada.Unchecked_Conversion (Address, Node_Ptr);
@@ -81,7 +86,7 @@ package body Ada.Finalization.Heap_Management is
       Needs_Header : Boolean := True)
    is
    begin
-      --  Allocation of a controlled object
+      --  Allocation of an object with controlled parts
 
       if Needs_Header then
 
@@ -99,7 +104,8 @@ package body Ada.Finalization.Heap_Management is
          begin
             --  Use the underlying pool to allocate enough space for the object
             --  and the list header. The returned address points to the list
-            --  header.
+            --  header. If locking is necessary, it will be done by the
+            --  underlying pool.
 
             Allocate
               (Collection.Base_Pool.all,
@@ -174,7 +180,7 @@ package body Ada.Finalization.Heap_Management is
       Has_Header   : Boolean := True)
    is
    begin
-      --  Deallocation of a controlled object
+      --  Deallocation of an object with controlled parts
 
       if Has_Header then
          declare
@@ -246,7 +252,7 @@ package body Ada.Finalization.Heap_Management is
      (Collection : in out Finalization_Collection)
    is
       function Head (L : Node_Ptr) return Node_Ptr;
-      --  Return the node which comes after the dummy head
+      --  Return the node that comes after the dummy head
 
       function Is_Dummy_Head (N : Node_Ptr) return Boolean;
       --  Determine whether a node acts as a dummy head. Such nodes do not
@@ -310,9 +316,10 @@ package body Ada.Finalization.Heap_Management is
    --  Start of processing for Finalize
 
    begin
-      --  Lock the collection to prevent any allocations while the objects are
-      --  being finalized. The collection remains locked because the associated
-      --  access type is about to go out of scope.
+      --  Set Finalization_Started to prevent any allocations of objects with
+      --  controlled parts during finalization. The associated access type is
+      --  about to go out of scope; Finalization_Started is never again
+      --  modified.
 
       Collection.Finalization_Started := True;
 
@@ -457,8 +464,8 @@ package body Ada.Finalization.Heap_Management is
             end if;
          end if;
 
-         --  The current element points back to null. This should never happen
-         --  since the list is circular.
+         --  The current element is null. This should never happen since the
+         --  list is circular.
 
          if N_Ptr.Prev = null then
             Put_Line ("null (ERROR)");
@@ -468,7 +475,7 @@ package body Ada.Finalization.Heap_Management is
          elsif N_Ptr.Prev.Next = N_Ptr then
             Put_Line ("^");
 
-         --  The current element points back to an erroneous element
+         --  The current element points to an erroneous element
 
          else
             Put_Line ("? (ERROR)");

gcc/ada/a-fihema.ads

@@ -69,8 +69,8 @@ package Ada.Finalization.Heap_Management is
       Needs_Header : Boolean := True);
    --  Allocate a chunk of memory described by Storage_Size and Alignment on
    --  Collection's underlying storage pool. Return the address of the chunk.
-   --  The routine creates a list header which precedes the chunk of memory is
-   --  flag Needs_Header is set. If allocated, the header is attached to the
+   --  The routine creates a list header which precedes the chunk of memory if
+   --  Needs_Header is True. If allocated, the header is attached to the
    --  Collection's objects. The interface to this routine is provided by
    --  Build_Allocate_Deallocate_Proc.
 
@@ -92,12 +92,12 @@ package Ada.Finalization.Heap_Management is
 
    overriding procedure Finalize
      (Collection : in out Finalization_Collection);
-   --  Traverse the objects of Collection, invoking Finalize_Address on eanch
-   --  of them. In the end, the routine destroys its dummy head and tail.
+   --  Traverse the objects of Collection, invoking Finalize_Address on each of
+   --  them. In the end, the routine destroys its dummy head and tail.
 
    overriding procedure Initialize
      (Collection : in out Finalization_Collection);
-   --  Create a new Collection by allocating a dummy head and tal
+   --  Create a new Collection by allocating a dummy head and tail
 
    procedure Set_Finalize_Address_Ptr
      (Collection : in out Finalization_Collection;
@@ -125,22 +125,25 @@ private
      new Ada.Finalization.Limited_Controlled with
    record
       Base_Pool : Any_Storage_Pool_Ptr;
-      --  All objects and node headers are allocated on this underlying pool,
+      --  All objects and node headers are allocated on this underlying pool;
       --  the collection is simply a wrapper around it.
 
       Objects : Node_Ptr;
       --  The head of a doubly linked list
 
       Finalize_Address : Finalize_Address_Ptr;
-      --  A reference to a routine which finalizes an object denoted by its
+      --  A reference to a routine that finalizes an object denoted by its
       --  address. The collection must be homogeneous since the same routine
       --  will be invoked for every allocated object when the pool is
       --  finalized.
 
       Finalization_Started : Boolean := False;
-      --  When the finalization of a collection takes place, any allocations on
-      --  the same collection are prohibited and the action must raise Program_
-      --  Error.
+      pragma Atomic (Finalization_Started);
+      --  When the finalization of a collection takes place, any allocations of
+      --  objects with controlled or protected parts on the same collection are
+      --  prohibited and the action must raise Program_Error. This needs to be
+      --  atomic, because it is accessed without Lock_Task/Unlock_Task. See
+      --  RM-4.8(10.2/2).
    end record;
 
    procedure pcol (Collection : Finalization_Collection);

gcc/ada/exp_ch5.adb

@@ -2923,7 +2923,7 @@ package body Exp_Ch5 is
                   --    declare
                   --       Id : Element_Type := Pack.Element (Cursor);
                   --    begin
-                  --       <original loop statments>
+                  --       <original loop statements>
                   --    end;
 
                   Stats := New_List (

gcc/ada/exp_ch7.adb

@@ -1138,7 +1138,7 @@ package body Exp_Ch7 is
 
       Jump_Alts : List_Id := No_List;
       --  Jump block alternatives. Depending on the value of the state counter,
-      --  the control flow jumps to a sequence of finalization statments. This
+      --  the control flow jumps to a sequence of finalization statements. This
       --  list contains the following:
       --
       --     when <counter value> =>
@@ -4623,6 +4623,8 @@ package body Exp_Ch7 is
      (Obj_Ref : Node_Id;
       Ptr_Typ : Entity_Id) return Node_Id
    is
+      pragma Assert (VM_Target /= No_VM);
+
       Loc : constant Source_Ptr := Sloc (Obj_Ref);
    begin
       return

gcc/ada/exp_ch7.ads

@@ -122,10 +122,11 @@ package Exp_Ch7 is
      (Obj_Ref : Node_Id;
       Ptr_Typ : Entity_Id) return Node_Id;
    --  Create a call to prepend an object to a finalization collection. Obj_Ref
-   --  is the object, Ptr_Typ is the access type that owns the collection.
+   --  is the object, Ptr_Typ is the access type that owns the collection. This
+   --  is used only for .NET/JVM, that is, when VM_Target /= No_VM.
    --  Generate the following:
    --
-   --    Ada.Finalization.Heap_Managment.Attach
+   --    Ada.Finalization.Heap_Management.Attach
    --      (<Ptr_Typ>FC,
    --       System.Finalization_Root.Root_Controlled_Ptr (Obj_Ref));
 

gcc/ada/exp_util.adb

@@ -418,7 +418,7 @@ package body Exp_Util is
       if not Needs_Finalization (Desig_Typ) then
          return;
 
-      --  The allocator or free statmenet has already been expanded and already
+      --  The allocator or free statement has already been expanded and already
       --  has a custom Allocate / Deallocate routine.
 
       elsif Nkind (Expr) = N_Allocator

gcc/ada/sem_ch12.adb

@@ -2124,7 +2124,7 @@ package body Sem_Ch12 is
          return Pack_Decl;
       end Build_Local_Package;
 
-   --  Start of processing for Analyze_Formal_Package
+   --  Start of processing for Analyze_Formal_Package_Declaration
 
    begin
       Text_IO_Kludge (Gen_Id);
@@ -2182,6 +2182,25 @@ package body Sem_Ch12 is
          end if;
       end if;
 
+      --  Check that name of formal package does not hide name of generic,
+      --  or its leading prefix. This check must be done separately because
+      --  the name of the generic has already been analyzed.
+
+      declare
+         Gen_Name : Entity_Id;
+
+      begin
+         Gen_Name := Gen_Id;
+         while Nkind (Gen_Name) = N_Expanded_Name loop
+            Gen_Name := Prefix (Gen_Name);
+         end loop;
+         if Chars (Gen_Name) = Chars (Pack_Id) then
+            Error_Msg_NE
+             ("& is hidden within declaration of formal package",
+               Gen_Id, Gen_Name);
+         end if;
+      end;
+
       if Box_Present (N)
         or else No (Generic_Associations (N))
         or else Nkind (First (Generic_Associations (N))) = N_Others_Choice

gcc/ada/sem_ch3.adb

@@ -17382,7 +17382,8 @@ package body Sem_Ch3 is
 
          --  GNAT allow its own definition of Limited_Controlled to disobey
          --  this rule in order in ease the implementation. This test is safe
-         --  because Root_Controlled is defined in a private system child.
+         --  because Root_Controlled is defined in a child of System that
+         --  normal programs are not supposed to use.
 
          elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
             Set_Is_Limited_Composite (Full_T);