Add new tests.

From-SVN: r127555

gcc/testsuite/gnat.dg/deref1.ads

+package deref1 is
+  type T is tagged limited null record;
+   procedure Op (Obj : in out T);
+end deref1;

gcc/testsuite/gnat.dg/deref2.ads

+with deref1;
+package deref2 is
+   type NT is tagged limited private;
+   
+   function PT_View (Obj : not null access NT)
+     return not null access deref1.T'Class;
+private
+   type PT (Obj : not null access NT) is new deref1.T with null record;
+   
+   type NT is tagged limited record
+      PT_View : aliased PT (NT'Access);
+   end record;
+end;

gcc/testsuite/gnat.dg/deref3.adb

+--  { dg-do compile }
+
+with deref2;
+procedure deref3 is
+   Obj : aliased deref2.NT;
+begin
+   deref2.PT_View (Obj'Access).Op;
+   Obj.PT_View.all.Op;
+   Obj.PT_View.Op;
+end;

gcc/testsuite/gnat.dg/discr_test.adb

+--  { dg-do compile }
+
+procedure Discr_Test is
+  procedure P is begin null; end P;
+
+  task type Tsk1 is
+    entry rvT;
+  end Tsk1;
+
+  task body Tsk1 is
+  begin
+    accept rvT;
+  end Tsk1;
+
+  task type Tsk2 (pS : not null access procedure) is
+    entry rvT;
+  end Tsk2;
+
+  task body Tsk2 is
+    tskT : Tsk1;
+  begin
+    accept rvT do
+      requeue tskT.rvT;
+    end rvT;
+    pS.all;
+  end;
+
+  Obj : Tsk2 (P'access);
+begin
+  Obj.rvT;
+end;

gcc/testsuite/gnat.dg/elim1.adb

+package body elim1 is
+   procedure d (a : t) is
+   begin
+      null;
+   end; 
+end;

gcc/testsuite/gnat.dg/elim1.ads

+pragma Eliminate (p, d);
+package elim1 is
+   type t is tagged null record;
+   procedure d (a : t);       
+end;

gcc/testsuite/gnat.dg/elim2.adb

+--  { dg-do run }
+
+with elim1;
+procedure elim2 is
+begin
+   null;
+end;

gcc/testsuite/gnat.dg/specs/limited1.ads

+--  { dg-do compile }
+
+package limited1 is
+   pragma Pure;
+   
+   type Buffer is limited interface;
+   type Synchronous_Buffer_Type is synchronized interface and Buffer;
+   type Client_Buffer_Type is new Synchronous_Buffer_Type with private;
+
+private
+   type Client_Buffer_Type is new Synchronous_Buffer_Type with null record;
+end limited1;