/usr/share/go-1.8/test/deferfin.go is in golang-1.8-src 1.8.3-2ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 | // run
// Copyright 2013 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.
// Test that defers do not prevent garbage collection.
package main
import (
"runtime"
"sync"
"sync/atomic"
"time"
)
var sink func()
func main() {
// Does not work on 32-bits due to partially conservative GC.
// Try to enable when we have fully precise GC.
if runtime.GOARCH != "amd64" {
return
}
// Likewise for gccgo.
if runtime.Compiler == "gccgo" {
return
}
N := 10
count := int32(N)
var wg sync.WaitGroup
wg.Add(N)
for i := 0; i < N; i++ {
go func() {
defer wg.Done()
v := new(string)
f := func() {
if *v != "" {
panic("oops")
}
}
if *v != "" {
// let the compiler think f escapes
sink = f
}
runtime.SetFinalizer(v, func(p *string) {
atomic.AddInt32(&count, -1)
})
defer f()
}()
}
wg.Wait()
for i := 0; i < 3; i++ {
time.Sleep(10 * time.Millisecond)
runtime.GC()
}
if count != 0 {
println(count, "out of", N, "finalizer are not called")
panic("not all finalizers are called")
}
}
|