| // run |
| |
| // Copyright 2022 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 main |
| |
| import "runtime" |
| |
| func main() { |
| if wait() { |
| panic("GC'd early") |
| } |
| m = nil |
| if !wait() { |
| panic("never GC'd") |
| } |
| } |
| |
| var m = New[int]().M |
| |
| func New[X any]() *T[X] { |
| p := new(T[X]) |
| runtime.SetFinalizer(p, func(*T[X]) { close(done) }) |
| return p |
| } |
| |
| type T[X any] [4]int // N.B., [4]int avoids runtime's tiny object allocator |
| |
| func (*T[X]) M() {} |
| |
| var done = make(chan int) |
| |
| func wait() bool { |
| for i := 0; i < 10; i++ { |
| runtime.GC() |
| select { |
| case <-done: |
| return true |
| default: |
| } |
| } |
| return false |
| } |
