fn = *(*unsafe.Pointer)(v.ptr)
	} else {
		fn = v.ptr
	}

	if fn == nil {
		panic("reflect.Value.Call: call of nil function")
	}

	isSlice := op == "CallSlice"
	n := t.NumIn()
	isVariadic := t.IsVariadic()
	if isSlice {
		if !isVariadic {
			panic("reflect: CallSlice of non-variadic function")
		}
		if len(in) < n {
			panic("reflect: CallSlice with too few input arguments")