def __init__(self):
        vstruct.VStruct.__init__(self)
        self.EnabledFeatures = v_uint64()
        self.EnabledVolatileFeatures = v_uint64()
        self.Size = v_uint32()
        self.OptimizedSave = v_uint32()
        self.Features = vstruct.VArray([ XSTATE_FEATURE() for i in xrange(64) ])