summaryrefslogtreecommitdiff
path: root/test/escape_slice.go
blob: 7f94a755b99efc5e02d6fbda84705aa1c793e7cf (plain)
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
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
// errorcheck -0 -m -l

// 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 escape analysis for slices.

package escape

import (
	"os"
	"strings"
)

var sink interface{}

func slice0() {
	var s []*int
	// BAD: i should not escape
	i := 0 // ERROR "moved to heap: i"
	s = append(s, &i)
	_ = s
}

func slice1() *int {
	var s []*int
	i := 0 // ERROR "moved to heap: i"
	s = append(s, &i)
	return s[0]
}

func slice2() []*int {
	var s []*int
	i := 0 // ERROR "moved to heap: i"
	s = append(s, &i)
	return s
}

func slice3() *int {
	var s []*int
	i := 0 // ERROR "moved to heap: i"
	s = append(s, &i)
	for _, p := range s {
		return p
	}
	return nil
}

func slice4(s []*int) { // ERROR "s does not escape"
	i := 0 // ERROR "moved to heap: i"
	s[0] = &i
}

func slice5(s []*int) { // ERROR "s does not escape"
	if s != nil {
		s = make([]*int, 10) // ERROR "make\(\[\]\*int, 10\) does not escape"
	}
	i := 0 // ERROR "moved to heap: i"
	s[0] = &i
}

func slice6() {
	s := make([]*int, 10) // ERROR "make\(\[\]\*int, 10\) does not escape"
	// BAD: i should not escape
	i := 0 // ERROR "moved to heap: i"
	s[0] = &i
	_ = s
}

func slice7() *int {
	s := make([]*int, 10) // ERROR "make\(\[\]\*int, 10\) does not escape"
	i := 0                // ERROR "moved to heap: i"
	s[0] = &i
	return s[0]
}

func slice8() {
	i := 0
	s := []*int{&i} // ERROR "\[\]\*int{...} does not escape"
	_ = s
}

func slice9() *int {
	i := 0          // ERROR "moved to heap: i"
	s := []*int{&i} // ERROR "\[\]\*int{...} does not escape"
	return s[0]
}

func slice10() []*int {
	i := 0          // ERROR "moved to heap: i"
	s := []*int{&i} // ERROR "\[\]\*int{...} escapes to heap"
	return s
}

func slice11() {
	i := 2
	s := make([]int, 2, 3) // ERROR "make\(\[\]int, 2, 3\) does not escape"
	s = make([]int, i, 3)  // ERROR "make\(\[\]int, i, 3\) does not escape"
	s = make([]int, i, 1)  // ERROR "make\(\[\]int, i, 1\) does not escape"
	_ = s
}

func slice12(x []int) *[1]int { // ERROR "leaking param: x to result ~r0 level=0$"
	return (*[1]int)(x)
}

func slice13(x []*int) [1]*int { // ERROR "leaking param: x to result ~r0 level=1$"
	return [1]*int(x)
}

func envForDir(dir string) []string { // ERROR "dir does not escape"
	env := os.Environ()
	return mergeEnvLists([]string{"PWD=" + dir}, env) // ERROR ".PWD=. \+ dir escapes to heap" "\[\]string{...} does not escape"
}

func mergeEnvLists(in, out []string) []string { // ERROR "leaking param content: in" "leaking param content: out" "leaking param: out to result ~r0 level=0"
NextVar:
	for _, inkv := range in {
		k := strings.SplitAfterN(inkv, "=", 2)[0]
		for i, outkv := range out {
			if strings.HasPrefix(outkv, k) {
				out[i] = inkv
				continue NextVar
			}
		}
		out = append(out, inkv)
	}
	return out
}

const (
	IPv4len = 4
	IPv6len = 16
)

var v4InV6Prefix = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff}

func IPv4(a, b, c, d byte) IP {
	p := make(IP, IPv6len) // ERROR "make\(IP, IPv6len\) escapes to heap"
	copy(p, v4InV6Prefix)
	p[12] = a
	p[13] = b
	p[14] = c
	p[15] = d
	return p
}

type IP []byte

type IPAddr struct {
	IP   IP
	Zone string // IPv6 scoped addressing zone
}

type resolveIPAddrTest struct {
	network       string
	litAddrOrName string
	addr          *IPAddr
	err           error
}

var resolveIPAddrTests = []resolveIPAddrTest{
	{"ip", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
	{"ip4", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
	{"ip4:icmp", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
}

func setupTestData() {
	resolveIPAddrTests = append(resolveIPAddrTests,
		[]resolveIPAddrTest{ // ERROR "\[\]resolveIPAddrTest{...} does not escape"
			{"ip",
				"localhost",
				&IPAddr{IP: IPv4(127, 0, 0, 1)}, // ERROR "&IPAddr{...} escapes to heap"
				nil},
			{"ip4",
				"localhost",
				&IPAddr{IP: IPv4(127, 0, 0, 1)}, // ERROR "&IPAddr{...} escapes to heap"
				nil},
		}...)
}