1 // run 2 3 // Copyright 2013 The Go Authors. All rights reserved. 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file. 6 7 package main 8 9 import ( 10 "runtime" 11 "sync" 12 "sync/atomic" 13 "time" 14 ) 15 16 const N = 10 17 var count int64 18 19 func run() error { 20 f1 := func() {} 21 f2 := func() { 22 func() { 23 f1() 24 }() 25 } 26 runtime.SetFinalizer(&f1, func(f *func()) { 27 atomic.AddInt64(&count, -1) 28 }) 29 go f2() 30 return nil 31 } 32 33 func main() { 34 // Does not work on 32-bits, or with gccgo, due to partially 35 // conservative GC. 36 // Try to enable when we have fully precise GC. 37 if runtime.GOARCH != "amd64" || runtime.Compiler == "gccgo" { 38 return 39 } 40 count = N 41 var wg sync.WaitGroup 42 wg.Add(N) 43 for i := 0; i < N; i++ { 44 go func() { 45 run() 46 wg.Done() 47 }() 48 } 49 wg.Wait() 50 for i := 0; i < 2*N; i++ { 51 time.Sleep(10 * time.Millisecond) 52 runtime.GC() 53 } 54 if count != 0 { 55 println(count, "out of", N, "finalizer are not called") 56 panic("not all finalizers are called") 57 } 58 } 59 60
