procedure A is
begin

   --  Raise Program_Error and catch it.
   begin
      raise Program_Error;
   exception
      when others =>
         null;
   end;

   --  Raise Constraint_Error and catch it.
   Begin
      raise Constraint_Error;
   Exception
      when others =>
         null;
   End;

   --  Cause an exception to be raised, and do not handle it.
   declare
      Var : Natural := 10;
   begin
      Var := - Var;
   end;

end A;