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// run
// Copyright 2021 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"
type T [4]int // N.B., [4]int avoids runtime's tiny object allocator
//go:noinline
func g(x []*T) ([]*T, []*T) { return x, x }
func main() {
const Jenny = 8675309
s := [10]*T{{Jenny}}
done := make(chan struct{})
runtime.SetFinalizer(s[0], func(p *T) { close(done) })
var h, _ interface{} = g(s[:])
if wait(done) {
panic("GC'd early")
}
if h.([]*T)[0][0] != Jenny {
panic("lost Jenny's number")
}
if !wait(done) {
panic("never GC'd")
}
}
func wait(done <-chan struct{}) bool {
for i := 0; i < 10; i++ {
runtime.GC()
select {
case <-done:
return true
default:
}
}
return false
}
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