1// run
2
3// Copyright 2018 The Go Authors. All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7// Verify that we don't consider a Go'd function's
8// arguments as pointers when they aren't.
9
10package main
11
12import (
13	"unsafe"
14)
15
16var badPtr uintptr
17
18var sink []byte
19
20func init() {
21	// Allocate large enough to use largeAlloc.
22	b := make([]byte, 1<<16-1)
23	sink = b // force heap allocation
24	//  Any space between the object and the end of page is invalid to point to.
25	badPtr = uintptr(unsafe.Pointer(&b[len(b)-1])) + 1
26}
27
28var throttle = make(chan struct{}, 10)
29
30func noPointerArgs(a, b, c, d uintptr) {
31	sink = make([]byte, 4096)
32	<-throttle
33}
34
35func main() {
36	const N = 1000
37	for i := 0; i < N; i++ {
38		throttle <- struct{}{}
39		go noPointerArgs(badPtr, badPtr, badPtr, badPtr)
40		sink = make([]byte, 4096)
41	}
42}
43