// Copyright 2023 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package p type S struct { a [1]int } func _(m map[int]S, key int) { m /* ERROR "cannot assign to m[key].a[0] (neither addressable nor a map index expression)" */ [key].a[0] = 0 }