1 // errorcheck -0 -m -l 2 3 // Copyright 2015 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 // Test escape analysis for slices. 8 9 package escape 10 11 import ( 12 "os" 13 "strings" 14 ) 15 16 var sink interface{} 17 18 func slice0() { 19 var s []*int 20 // BAD: i should not escape 21 i := 0 // ERROR "moved to heap: i" 22 s = append(s, &i) // ERROR "&i escapes to heap" 23 _ = s 24 } 25 26 func slice1() *int { 27 var s []*int 28 i := 0 // ERROR "moved to heap: i" 29 s = append(s, &i) // ERROR "&i escapes to heap" 30 return s[0] 31 } 32 33 func slice2() []*int { 34 var s []*int 35 i := 0 // ERROR "moved to heap: i" 36 s = append(s, &i) // ERROR "&i escapes to heap" 37 return s 38 } 39 40 func slice3() *int { 41 var s []*int 42 i := 0 // ERROR "moved to heap: i" 43 s = append(s, &i) // ERROR "&i escapes to heap" 44 for _, p := range s { 45 return p 46 } 47 return nil 48 } 49 50 func slice4(s []*int) { // ERROR "s does not escape" 51 i := 0 // ERROR "moved to heap: i" 52 s[0] = &i // ERROR "&i escapes to heap" 53 } 54 55 func slice5(s []*int) { // ERROR "s does not escape" 56 if s != nil { 57 s = make([]*int, 10) // ERROR "make\(\[\]\*int, 10\) does not escape" 58 } 59 i := 0 // ERROR "moved to heap: i" 60 s[0] = &i // ERROR "&i escapes to heap" 61 } 62 63 func slice6() { 64 s := make([]*int, 10) // ERROR "make\(\[\]\*int, 10\) does not escape" 65 // BAD: i should not escape 66 i := 0 // ERROR "moved to heap: i" 67 s[0] = &i // ERROR "&i escapes to heap" 68 _ = s 69 } 70 71 func slice7() *int { 72 s := make([]*int, 10) // ERROR "make\(\[\]\*int, 10\) does not escape" 73 i := 0 // ERROR "moved to heap: i" 74 s[0] = &i // ERROR "&i escapes to heap" 75 return s[0] 76 } 77 78 func slice8() { 79 i := 0 80 s := []*int{&i} // ERROR "&i does not escape" "literal does not escape" 81 _ = s 82 } 83 84 func slice9() *int { 85 i := 0 // ERROR "moved to heap: i" 86 s := []*int{&i} // ERROR "&i escapes to heap" "literal does not escape" 87 return s[0] 88 } 89 90 func slice10() []*int { 91 i := 0 // ERROR "moved to heap: i" 92 s := []*int{&i} // ERROR "&i escapes to heap" "literal escapes to heap" 93 return s 94 } 95 96 func envForDir(dir string) []string { // ERROR "dir does not escape" 97 env := os.Environ() 98 return mergeEnvLists([]string{"PWD=" + dir}, env) // ERROR ".PWD=. \+ dir escapes to heap" "\[\]string literal does not escape" 99 } 100 101 func mergeEnvLists(in, out []string) []string { // ERROR "leaking param content: in" "leaking param content: out" "leaking param: out to result ~r2 level=0" 102 NextVar: 103 for _, inkv := range in { 104 k := strings.SplitAfterN(inkv, "=", 2)[0] 105 for i, outkv := range out { 106 if strings.HasPrefix(outkv, k) { 107 out[i] = inkv 108 continue NextVar 109 } 110 } 111 out = append(out, inkv) 112 } 113 return out 114 } 115 116 const ( 117 IPv4len = 4 118 IPv6len = 16 119 ) 120 121 var v4InV6Prefix = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff} 122 123 func IPv4(a, b, c, d byte) IP { 124 p := make(IP, IPv6len) // ERROR "make\(IP, IPv6len\) escapes to heap" 125 copy(p, v4InV6Prefix) 126 p[12] = a 127 p[13] = b 128 p[14] = c 129 p[15] = d 130 return p 131 } 132 133 type IP []byte 134 135 type IPAddr struct { 136 IP IP 137 Zone string // IPv6 scoped addressing zone 138 } 139 140 type resolveIPAddrTest struct { 141 network string 142 litAddrOrName string 143 addr *IPAddr 144 err error 145 } 146 147 var resolveIPAddrTests = []resolveIPAddrTest{ 148 {"ip", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil}, 149 {"ip4", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil}, 150 {"ip4:icmp", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil}, 151 } 152 153 func setupTestData() { 154 resolveIPAddrTests = append(resolveIPAddrTests, 155 []resolveIPAddrTest{ // ERROR "\[\]resolveIPAddrTest literal does not escape" 156 {"ip", 157 "localhost", 158 &IPAddr{IP: IPv4(127, 0, 0, 1)}, // ERROR "&IPAddr literal escapes to heap" 159 nil}, 160 {"ip4", 161 "localhost", 162 &IPAddr{IP: IPv4(127, 0, 0, 1)}, // ERROR "&IPAddr literal escapes to heap" 163 nil}, 164 }...) 165 } 166
