/usr/share/go-1.6/test/fixedbugs/issue13471.go is in golang-1.6-src 1.6.1-0ubuntu1.
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 | // errorcheck
// 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.
// Tests for golang.org/issue/13471
package main
func main() {
	const _ int64 = 1e646456992 // ERROR "1e\+646456992 overflows integer"
	const _ int32 = 1e64645699  // ERROR "1e\+64645699 overflows integer"
	const _ int16 = 1e6464569   // ERROR "1e\+6464569 overflows integer"
	const _ int8 = 1e646456     // ERROR "1e\+646456 overflows integer"
	const _ int = 1e64645       // ERROR "1e\+64645 overflows integer"
	const _ uint64 = 1e646456992 // ERROR "1e\+646456992 overflows integer"
	const _ uint32 = 1e64645699  // ERROR "1e\+64645699 overflows integer"
	const _ uint16 = 1e6464569   // ERROR "1e\+6464569 overflows integer"
	const _ uint8 = 1e646456     // ERROR "1e\+646456 overflows integer"
	const _ uint = 1e64645       // ERROR "1e\+64645 overflows integer"
	const _ rune = 1e64645 // ERROR "1e\+64645 overflows integer"
}
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