gcc/testsuite/gnat.dg/interface5.ads

   1 package interface5 is
   2    type B is tagged null record;
   3
   4    type I is interface;
   5    function F (Object : I) return access I is abstract;
   6
   7    type Child is new B and I with null record;
   8    function F (Object : Child) return access Child;
   9 end interface5;