// 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 "literal does not escape" _ = s } func slice9() *int { i := 0 // ERROR "moved to heap: i" s := []*int{&i} // ERROR "literal does not escape" return s[0] } func slice10() []*int { i := 0 // ERROR "moved to heap: i" s := []*int{&i} // ERROR "literal 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 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 literal does not escape" } func mergeEnvLists(in, out []string) []string { // ERROR "leaking param content: in" "leaking param content: out" "leaking param: out to result ~r2 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 literal does not escape" {"ip", "localhost", &IPAddr{IP: IPv4(127, 0, 0, 1)}, // ERROR "&IPAddr literal escapes to heap" nil}, {"ip4", "localhost", &IPAddr{IP: IPv4(127, 0, 0, 1)}, // ERROR "&IPAddr literal escapes to heap" nil}, }...) }