This file is indexed.

/usr/share/go-1.8/test/fixedbugs/issue11256.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
// run

// Copyright 2015 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 stack barriers are reset when a goroutine exits without
// returning.

package main

import (
	"runtime"
	"sync/atomic"
	"time"
)

func main() {
	// Let the garbage collector run concurrently.
	runtime.GOMAXPROCS(2)

	var x [100][]byte

	for i := range x {
		var done int32

		go func() {
			// Use enough stack to get stack barriers, but
			// not so much that we go over _FixedStack.
			// There's a very narrow window here on most
			// OSs, so we basically can't do anything (not
			// even a time.Sleep or a channel).
			var buf [1024]byte
			buf[0]++
			for atomic.LoadInt32(&done) == 0 {
				runtime.Gosched()
			}
			atomic.StoreInt32(&done, 0)
			// Exit without unwinding stack barriers.
			runtime.Goexit()
		}()

		// Generate some garbage.
		x[i] = make([]byte, 1024*1024)

		// Give GC some time to install stack barriers in the G.
		time.Sleep(50 * time.Microsecond)
		atomic.StoreInt32(&done, 1)
		for atomic.LoadInt32(&done) == 1 {
			runtime.Gosched()
		}
	}
}