modernc.org/gc@v1.0.1-0.20240304020402-f0dba7c97c2b/testdata/errchk/test/escape_closure.go (about) 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 closure arguments. 8 9 package escape 10 11 var sink interface{} 12 13 func ClosureCallArgs0() { 14 x := 0 // ERROR "moved to heap: x" 15 func(p *int) { // ERROR "p does not escape" "func literal does not escape" 16 *p = 1 17 // BAD: x should not escape to heap here 18 }(&x) // ERROR "&x escapes to heap" 19 } 20 21 func ClosureCallArgs1() { 22 x := 0 // ERROR "moved to heap: x" 23 for { 24 func(p *int) { // ERROR "p does not escape" "func literal does not escape" 25 *p = 1 26 // BAD: x should not escape to heap here 27 }(&x) // ERROR "&x escapes to heap" 28 } 29 } 30 31 func ClosureCallArgs2() { 32 for { 33 // BAD: x should not escape here 34 x := 0 // ERROR "moved to heap: x" 35 func(p *int) { // ERROR "p does not escape" "func literal does not escape" 36 *p = 1 37 }(&x) // ERROR "&x escapes to heap" 38 } 39 } 40 41 func ClosureCallArgs3() { 42 x := 0 // ERROR "moved to heap: x" 43 func(p *int) { // ERROR "leaking param: p" "func literal does not escape" 44 sink = p // ERROR "p escapes to heap" 45 }(&x) // ERROR "&x escapes to heap" 46 } 47 48 func ClosureCallArgs4() { 49 // BAD: x should not leak here 50 x := 0 // ERROR "moved to heap: x" 51 _ = func(p *int) *int { // ERROR "leaking param: p to result ~r1" "func literal does not escape" 52 return p 53 }(&x) // ERROR "&x escapes to heap" 54 } 55 56 func ClosureCallArgs5() { 57 x := 0 // ERROR "moved to heap: x" 58 sink = func(p *int) *int { // ERROR "leaking param: p to result ~r1" "func literal does not escape" "\(func literal\)\(&x\) escapes to heap" 59 return p 60 }(&x) // ERROR "&x escapes to heap" 61 } 62 63 func ClosureCallArgs6() { 64 x := 0 // ERROR "moved to heap: x" 65 func(p *int) { // ERROR "moved to heap: p" "func literal does not escape" 66 sink = &p // ERROR "&p escapes to heap" 67 }(&x) // ERROR "&x escapes to heap" 68 } 69 70 func ClosureCallArgs7() { 71 var pp *int 72 for { 73 x := 0 // ERROR "moved to heap: x" 74 func(p *int) { // ERROR "leaking param: p" "func literal does not escape" 75 pp = p 76 }(&x) // ERROR "&x escapes to heap" 77 } 78 _ = pp 79 } 80 81 func ClosureCallArgs8() { 82 x := 0 // ERROR "moved to heap: x" 83 defer func(p *int) { // ERROR "p does not escape" "func literal does not escape" 84 *p = 1 85 // BAD: x should not escape to heap here 86 }(&x) // ERROR "&x escapes to heap" 87 } 88 89 func ClosureCallArgs9() { 90 // BAD: x should not leak 91 x := 0 // ERROR "moved to heap: x" 92 for { 93 defer func(p *int) { // ERROR "func literal escapes to heap" "p does not escape" 94 *p = 1 95 }(&x) // ERROR "&x escapes to heap" 96 } 97 } 98 99 func ClosureCallArgs10() { 100 for { 101 x := 0 // ERROR "moved to heap: x" 102 defer func(p *int) { // ERROR "func literal escapes to heap" "p does not escape" 103 *p = 1 104 }(&x) // ERROR "&x escapes to heap" 105 } 106 } 107 108 func ClosureCallArgs11() { 109 x := 0 // ERROR "moved to heap: x" 110 defer func(p *int) { // ERROR "leaking param: p" "func literal does not escape" 111 sink = p // ERROR "p escapes to heap" 112 }(&x) // ERROR "&x escapes to heap" 113 } 114 115 func ClosureCallArgs12() { 116 // BAD: x should not leak 117 x := 0 // ERROR "moved to heap: x" 118 defer func(p *int) *int { // ERROR "leaking param: p to result ~r1" "func literal does not escape" 119 return p 120 }(&x) // ERROR "&x escapes to heap" 121 } 122 123 func ClosureCallArgs13() { 124 x := 0 // ERROR "moved to heap: x" 125 defer func(p *int) { // ERROR "moved to heap: p" "func literal does not escape" 126 sink = &p // ERROR "&p escapes to heap" 127 }(&x) // ERROR "&x escapes to heap" 128 } 129 130 func ClosureCallArgs14() { 131 x := 0 // ERROR "moved to heap: x" 132 // BAD: &x should not escape here 133 p := &x // ERROR "moved to heap: p" "&x escapes to heap" 134 _ = func(p **int) *int { // ERROR "leaking param: p to result ~r1 level=1" "func literal does not escape" 135 return *p 136 // BAD: p should not escape here 137 }(&p) // ERROR "&p escapes to heap" 138 } 139 140 func ClosureCallArgs15() { 141 x := 0 // ERROR "moved to heap: x" 142 p := &x // ERROR "moved to heap: p" "&x escapes to heap" 143 sink = func(p **int) *int { // ERROR "leaking param: p to result ~r1 level=1" "func literal does not escape" "\(func literal\)\(&p\) escapes to heap" 144 return *p 145 // BAD: p should not escape here 146 }(&p) // ERROR "&p escapes to heap" 147 } 148 149 func ClosureLeak1(s string) string { // ERROR "ClosureLeak1 s does not escape" 150 t := s + "YYYY" // ERROR "escapes to heap" 151 return ClosureLeak1a(t) // ERROR "ClosureLeak1 ... argument does not escape" 152 } 153 154 // See #14409 -- returning part of captured var leaks it. 155 func ClosureLeak1a(a ...string) string { // ERROR "leaking param: a to result ~r1 level=1" 156 return func() string { // ERROR "ClosureLeak1a func literal does not escape" 157 return a[0] 158 }() 159 } 160 161 func ClosureLeak2(s string) string { // ERROR "ClosureLeak2 s does not escape" 162 t := s + "YYYY" // ERROR "escapes to heap" 163 c := ClosureLeak2a(t) // ERROR "ClosureLeak2 ... argument does not escape" 164 return c 165 } 166 func ClosureLeak2a(a ...string) string { // ERROR "leaking param: a to result ~r1 level=1" 167 return ClosureLeak2b(func() string { // ERROR "ClosureLeak2a func literal does not escape" 168 return a[0] 169 }) 170 } 171 func ClosureLeak2b(f func() string) string { // ERROR "leaking param: f to result ~r1 level=1" 172 return f() 173 }