// errorcheck -0 -l -live // Copyright 2014 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. // liveness tests with inlining disabled. // see also live2.go. package main func f1() { var x *int print(&x) // ERROR "live at call to printpointer: x$" print(&x) // ERROR "live at call to printpointer: x$" } func f2(b bool) { if b { print(0) // nothing live here return } var x *int print(&x) // ERROR "live at call to printpointer: x$" print(&x) // ERROR "live at call to printpointer: x$" } func f3(b bool) { // Because x and y are ambiguously live, they appear // live throughout the function, to avoid being poisoned // in GODEBUG=gcdead=1 mode. print(0) // ERROR "live at call to printint: x y$" if b == false { print(0) // ERROR "live at call to printint: x y$" return } if b { var x *int print(&x) // ERROR "live at call to printpointer: x y$" print(&x) // ERROR "live at call to printpointer: x y$" } else { var y *int print(&y) // ERROR "live at call to printpointer: x y$" print(&y) // ERROR "live at call to printpointer: x y$" } print(0) // ERROR "live at call to printint: x y$" "x \(type \*int\) is ambiguously live" "y \(type \*int\) is ambiguously live" } // The old algorithm treated x as live on all code that // could flow to a return statement, so it included the // function entry and code above the declaration of x // but would not include an indirect use of x in an infinite loop. // Check that these cases are handled correctly. func f4(b1, b2 bool) { // x not live here if b2 { print(0) // x not live here return } var z **int x := new(int) *x = 42 z = &x print(**z) // ERROR "live at call to printint: x z$" if b2 { print(1) // ERROR "live at call to printint: x$" return } for { print(**z) // ERROR "live at call to printint: x z$" } } func f5(b1 bool) { var z **int if b1 { x := new(int) *x = 42 z = &x } else { y := new(int) *y = 54 z = &y } print(**z) // ERROR "live at call to printint: x y$" "x \(type \*int\) is ambiguously live" "y \(type \*int\) is ambiguously live" } // confusion about the _ result used to cause spurious "live at entry to f6: _". func f6() (_, y string) { y = "hello" return } // confusion about addressed results used to cause "live at entry to f7: x". func f7() (x string) { _ = &x x = "hello" return } // ignoring block returns used to cause "live at entry to f8: x, y". func f8() (x, y string) { return g8() } func g8() (string, string) // ignoring block assignments used to cause "live at entry to f9: x" // issue 7205 var i9 interface{} func f9() bool { g8() x := i9 return x != 99 } // liveness formerly confused by UNDEF followed by RET, // leading to "live at entry to f10: ~r1" (unnamed result). func f10() string { panic(1) } // liveness formerly confused by select, thinking runtime.selectgo // can return to next instruction; it always jumps elsewhere. // note that you have to use at least two cases in the select // to get a true select; smaller selects compile to optimized helper functions. var c chan *int var b bool // this used to have a spurious "live at entry to f11a: ~r0" func f11a() *int { select { // ERROR "live at call to newselect: autotmp" "live at call to selectgo: autotmp" case <-c: // ERROR "live at call to selectrecv: autotmp" return nil case <-c: // ERROR "live at call to selectrecv: autotmp" return nil } } func f11b() *int { p := new(int) if b { // At this point p is dead: the code here cannot // get to the bottom of the function. // This used to have a spurious "live at call to printint: p". print(1) // nothing live here! select { // ERROR "live at call to newselect: autotmp" "live at call to selectgo: autotmp" case <-c: // ERROR "live at call to selectrecv: autotmp" return nil case <-c: // ERROR "live at call to selectrecv: autotmp" return nil } } println(*p) return nil } func f11c() *int { p := new(int) if b { // Unlike previous, the cases in this select fall through, // so we can get to the println, so p is not dead. print(1) // ERROR "live at call to printint: p" select { // ERROR "live at call to newselect: autotmp.* p" "live at call to selectgo: autotmp.* p" case <-c: // ERROR "live at call to selectrecv: autotmp.* p" case <-c: // ERROR "live at call to selectrecv: autotmp.* p" } } println(*p) return nil } // similarly, select{} does not fall through. // this used to have a spurious "live at entry to f12: ~r0". func f12() *int { if b { select{} } else { return nil } } // incorrectly placed VARDEF annotations can cause missing liveness annotations. // this used to be missing the fact that s is live during the call to g13 (because it is // needed for the call to h13). func f13() { s := "hello" s = h13(s, g13(s)) // ERROR "live at call to g13: s" } func g13(string) string func h13(string, string) string // more incorrectly placed VARDEF. func f14() { x := g14() print(&x) // ERROR "live at call to printpointer: x" } func g14() string func f15() { var x string _ = &x x = g15() // ERROR "live at call to g15: x" print(x) // ERROR "live at call to printstring: x" } func g15() string // Checking that various temporaries do not persist or cause // ambiguously live values that must be zeroed. // The exact temporary names are inconsequential but we are // trying to check that there is only one at any given site, // and also that none show up in "ambiguously live" messages. var m map[string]int func f16() { if b { delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$" } delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$" delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$" } var m2s map[string]*byte var m2 map[[2]string]*byte var x2 [2]string var bp *byte func f17a() { // value temporary only if b { m2[x2] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+$" } m2[x2] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+$" m2[x2] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+$" } func f17b() { // key temporary only if b { m2s["x"] = bp // ERROR "live at call to mapassign1: autotmp_[0-9]+$" } m2s["x"] = bp // ERROR "live at call to mapassign1: autotmp_[0-9]+$" m2s["x"] = bp // ERROR "live at call to mapassign1: autotmp_[0-9]+$" } func f17c() { // key and value temporaries if b { m2s["x"] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$" } m2s["x"] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$" m2s["x"] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$" } func g18() [2]string func f18() { // key temporary for mapaccess. // temporary introduced by orderexpr. var z *byte if b { z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" } z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" print(z) } var ch chan *byte func f19() { // dest temporary for channel receive. var z *byte if b { z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$" } z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$" z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$" print(z) } func f20() { // src temporary for channel send if b { ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$" } ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$" ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$" } func f21() { // key temporary for mapaccess using array literal key. var z *byte if b { z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" } z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" print(z) } func f23() { // key temporary for two-result map access using array literal key. var z *byte var ok bool if b { z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$" } z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$" z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$" print(z, ok) } func f24() { // key temporary for map access using array literal key. // value temporary too. if b { m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$" } m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$" m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$" } // defer should not cause spurious ambiguously live variables func f25(b bool) { defer g25() if b { return } var x string _ = &x x = g15() // ERROR "live at call to g15: x" print(x) // ERROR "live at call to printstring: x" } // ERROR "live at call to deferreturn: x" func g25() // non-escaping ... slices passed to function call should die on return, // so that the temporaries do not stack and do not cause ambiguously // live variables. func f26(b bool) { if b { print26(1,2,3) // ERROR "live at call to print26: autotmp_[0-9]+$" } print26(4,5,6) // ERROR "live at call to print26: autotmp_[0-9]+$" print26(7,8,9) // ERROR "live at call to print26: autotmp_[0-9]+$" println() } //go:noescape func print26(...interface{}) // non-escaping closures passed to function call should die on return func f27(b bool) { x := 0 if b { call27(func() {x++}) // ERROR "live at call to call27: autotmp_[0-9]+$" } call27(func() {x++}) // ERROR "live at call to call27: autotmp_[0-9]+$" call27(func() {x++}) // ERROR "live at call to call27: autotmp_[0-9]+$" println() } // but defer does escape to later execution in the function func f27defer(b bool) { x := 0 if b { defer call27(func() {x++}) // ERROR "live at call to deferproc: autotmp_[0-9]+$" "live at call to deferreturn: autotmp_[0-9]+$" } defer call27(func() {x++}) // ERROR "live at call to deferproc: autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to deferreturn: autotmp_[0-9]+ autotmp_[0-9]+$" "ambiguously live" println() // ERROR "live at call to printnl: autotmp_[0-9]+ autotmp_[0-9]+$" } // ERROR "live at call to deferreturn: autotmp_[0-9]+ autotmp_[0-9]+$" // and newproc (go) escapes to the heap func f27go(b bool) { x := 0 if b { go call27(func() {x++}) // ERROR "live at call to new: &x" "live at call to newproc: &x$" } go call27(func() {x++}) // ERROR "live at call to new: &x" println() } //go:noescape func call27(func()) // concatstring slice should die on return var s1, s2, s3, s4, s5, s6, s7, s8, s9, s10 string func f28(b bool) { if b { print(s1+s2+s3+s4+s5+s6+s7+s8+s9+s10) // ERROR "live at call to concatstrings: autotmp_[0-9]+$" "live at call to printstring: autotmp_[0-9]+$" } print(s1+s2+s3+s4+s5+s6+s7+s8+s9+s10) // ERROR "live at call to concatstrings: autotmp_[0-9]+$" "live at call to printstring: autotmp_[0-9]+$" print(s1+s2+s3+s4+s5+s6+s7+s8+s9+s10) // ERROR "live at call to concatstrings: autotmp_[0-9]+$" "live at call to printstring: autotmp_[0-9]+$" } // map iterator should die on end of range loop func f29(b bool) { if b { for k := range m { // ERROR "live at call to mapiterinit: autotmp_[0-9]+$" "live at call to mapiternext: autotmp_[0-9]+$" print(k) // ERROR "live at call to printstring: autotmp_[0-9]+$" } } for k := range m { // ERROR "live at call to mapiterinit: autotmp_[0-9]+$" "live at call to mapiternext: autotmp_[0-9]+$" print(k) // ERROR "live at call to printstring: autotmp_[0-9]+$" } for k := range m { // ERROR "live at call to mapiterinit: autotmp_[0-9]+$" "live at call to mapiternext: autotmp_[0-9]+$" print(k) // ERROR "live at call to printstring: autotmp_[0-9]+$" } } // copy of array of pointers should die at end of range loop var ptrarr [10]*int func f30(b bool) { // two live temps during print(p): // the copy of ptrarr and the internal iterator pointer. if b { for _, p := range ptrarr { print(p) // ERROR "live at call to printpointer: autotmp_[0-9]+ autotmp_[0-9]+$" } } for _, p := range ptrarr { print(p) // ERROR "live at call to printpointer: autotmp_[0-9]+ autotmp_[0-9]+$" } for _, p := range ptrarr { print(p) // ERROR "live at call to printpointer: autotmp_[0-9]+ autotmp_[0-9]+$" } } // conversion to interface should not leave temporary behind func f31(b1, b2, b3 bool) { if b1 { g31("a") // ERROR "live at call to convT2E: autotmp_[0-9]+$" "live at call to g31: autotmp_[0-9]+$" } if b2 { h31("b") // ERROR "live at call to new: autotmp_[0-9]+$" "live at call to convT2E: autotmp_[0-9]+ autotmp_[0-9]+$" "live at call to h31: autotmp_[0-9]+$" } if b3 { panic("asdf") // ERROR "live at call to convT2E: autotmp_[0-9]+$" "live at call to panic: autotmp_[0-9]+$" } print(b3) } func g31(interface{}) func h31(...interface{}) // non-escaping partial functions passed to function call should die on return type T32 int func (t *T32) Inc() { // ERROR "live at entry" *t++ } var t32 T32 func f32(b bool) { if b { call32(t32.Inc) // ERROR "live at call to call32: autotmp_[0-9]+$" } call32(t32.Inc) // ERROR "live at call to call32: autotmp_[0-9]+$" call32(t32.Inc) // ERROR "live at call to call32: autotmp_[0-9]+$" } //go:noescape func call32(func()) // temporaries introduced during if conditions and && || expressions // should die once the condition has been acted upon. var m33 map[interface{}]int func f33() { if m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" println() return } else { println() } println() } func f34() { if m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" println() return } println() } func f35() { if m33[nil] == 0 && m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" println() return } println() } func f36() { if m33[nil] == 0 || m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" println() return } println() } func f37() { if (m33[nil] == 0 || m33[nil] == 0) && m33[nil] == 0 { // ERROR "live at call to mapaccess1: autotmp_[0-9]+$" println() return } println() } // select temps should disappear in the case bodies var c38 chan string func fc38() chan string func fi38(int) *string func fb38() *bool func f38(b bool) { // we don't care what temps are printed on the lines with output. // we care that the println lines have no live variables // and therefore no output. if b { select { // ERROR "live at call" case <-fc38(): // ERROR "live at call" println() case fc38() <- *fi38(1): // ERROR "live at call" println() case *fi38(2) = <-fc38(): // ERROR "live at call" println() case *fi38(3), *fb38() = <-fc38(): // ERROR "live at call" println() } println() } println() } // issue 8097: mishandling of x = x during return. func f39() (x []int) { x = []int{1} println() // ERROR "live at call to printnl: x" return x } func f39a() (x []int) { x = []int{1} println() // ERROR "live at call to printnl: x" return } func f39b() (x [10]*int) { x = [10]*int{new(int)} // ERROR "live at call to new: x" println() // ERROR "live at call to printnl: x" return x } func f39c() (x [10]*int) { x = [10]*int{new(int)} // ERROR "live at call to new: x" println() // ERROR "live at call to printnl: x" return } // issue 8142: lost 'addrtaken' bit on inlined variables. // no inlining in this test, so just checking that non-inlined works. type T40 struct { m map[int]int } func newT40() *T40 { ret := T40{ // ERROR "live at call to makemap: &ret" make(map[int]int), } return &ret } func bad40() { t := newT40() println() _ = t } func good40() { ret := T40{ // ERROR "live at call to makemap: ret" make(map[int]int), } t := &ret println() // ERROR "live at call to printnl: ret" _ = t }