go/test/gcstring.go

49 строки
872 B
Go

// run
// Copyright 2014 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 s[len(s):] - which can point past the end of the allocated block -
// does not confuse the garbage collector.
package main
import (
"runtime"
"time"
)
type T struct {
ptr **int
pad [120]byte
}
var things []interface{}
func main() {
setup()
runtime.GC()
runtime.GC()
time.Sleep(10*time.Millisecond)
runtime.GC()
runtime.GC()
time.Sleep(10*time.Millisecond)
}
func setup() {
var Ts []interface{}
buf := make([]byte, 128)
for i := 0; i < 10000; i++ {
s := string(buf)
t := &T{ptr: new(*int)}
runtime.SetFinalizer(t.ptr, func(**int) { panic("*int freed too early") })
Ts = append(Ts, t)
things = append(things, s[len(s):])
}
things = append(things, Ts...)
}