mirror of https://github.com/golang/go.git
333 lines
8.3 KiB
Go
333 lines
8.3 KiB
Go
// errorcheck -0 -l -live
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// Copyright 2014 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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func f1() {
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var x *int
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print(&x) // ERROR "live at call to printpointer: x$"
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print(&x) // ERROR "live at call to printpointer: x$"
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}
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func f2(b bool) {
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if b {
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print(0) // nothing live here
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return
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}
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var x *int
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print(&x) // ERROR "live at call to printpointer: x$"
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print(&x) // ERROR "live at call to printpointer: x$"
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}
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func f3(b bool) {
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print(0)
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if b == false {
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print(0) // nothing live here
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return
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}
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if b {
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var x *int
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print(&x) // ERROR "live at call to printpointer: x$"
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print(&x) // ERROR "live at call to printpointer: x$"
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} else {
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var y *int
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print(&y) // ERROR "live at call to printpointer: y$"
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print(&y) // ERROR "live at call to printpointer: y$"
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}
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print(0) // ERROR "live at call to printint: x y$" "x \(type \*int\) is ambiguously live" "y \(type \*int\) is ambiguously live"
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}
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// The old algorithm treated x as live on all code that
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// could flow to a return statement, so it included the
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// function entry and code above the declaration of x
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// but would not include an indirect use of x in an infinite loop.
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// Check that these cases are handled correctly.
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func f4(b1, b2 bool) { // x not live here
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if b2 {
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print(0) // x not live here
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return
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}
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var z **int
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x := new(int)
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*x = 42
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z = &x
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print(**z) // ERROR "live at call to printint: x z$"
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if b2 {
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print(1) // ERROR "live at call to printint: x$"
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return
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}
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for {
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print(**z) // ERROR "live at call to printint: x z$"
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}
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}
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func f5(b1 bool) {
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var z **int
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if b1 {
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x := new(int)
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*x = 42
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z = &x
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} else {
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y := new(int)
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*y = 54
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z = &y
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}
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print(**z) // ERROR "live at call to printint: x y$" "x \(type \*int\) is ambiguously live" "y \(type \*int\) is ambiguously live"
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}
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// confusion about the _ result used to cause spurious "live at entry to f6: _".
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func f6() (_, y string) {
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y = "hello"
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return
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}
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// confusion about addressed results used to cause "live at entry to f7: x".
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func f7() (x string) {
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_ = &x
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x = "hello"
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return
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}
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// ignoring block returns used to cause "live at entry to f8: x, y".
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func f8() (x, y string) {
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return g8()
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}
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func g8() (string, string)
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// ignoring block assignments used to cause "live at entry to f9: x"
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// issue 7205
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var i9 interface{}
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func f9() bool {
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g8()
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x := i9
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return x != 99
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}
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// liveness formerly confused by UNDEF followed by RET,
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// leading to "live at entry to f10: ~r1" (unnamed result).
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func f10() string {
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panic(1)
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}
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// liveness formerly confused by select, thinking runtime.selectgo
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// can return to next instruction; it always jumps elsewhere.
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// note that you have to use at least two cases in the select
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// to get a true select; smaller selects compile to optimized helper functions.
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var c chan *int
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var b bool
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// this used to have a spurious "live at entry to f11a: ~r0"
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func f11a() *int {
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select { // ERROR "live at call to selectgo: autotmp"
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case <-c: // ERROR "live at call to selectrecv: autotmp"
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return nil
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case <-c: // ERROR "live at call to selectrecv: autotmp"
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return nil
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}
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}
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func f11b() *int {
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p := new(int)
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if b {
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// At this point p is dead: the code here cannot
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// get to the bottom of the function.
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// This used to have a spurious "live at call to printint: p".
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print(1) // nothing live here!
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select { // ERROR "live at call to selectgo: autotmp"
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case <-c: // ERROR "live at call to selectrecv: autotmp"
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return nil
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case <-c: // ERROR "live at call to selectrecv: autotmp"
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return nil
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}
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}
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println(*p)
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return nil
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}
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func f11c() *int {
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p := new(int)
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if b {
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// Unlike previous, the cases in this select fall through,
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// so we can get to the println, so p is not dead.
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print(1) // ERROR "live at call to printint: p"
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select { // ERROR "live at call to newselect: p" "live at call to selectgo: autotmp.* p"
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case <-c: // ERROR "live at call to selectrecv: autotmp.* p"
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case <-c: // ERROR "live at call to selectrecv: autotmp.* p"
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}
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}
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println(*p)
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return nil
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}
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// similarly, select{} does not fall through.
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// this used to have a spurious "live at entry to f12: ~r0".
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func f12() *int {
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if b {
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select{}
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} else {
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return nil
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}
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}
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// incorrectly placed VARDEF annotations can cause missing liveness annotations.
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// this used to be missing the fact that s is live during the call to g13 (because it is
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// needed for the call to h13).
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func f13() {
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s := "hello"
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s = h13(s, g13(s)) // ERROR "live at call to g13: s"
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}
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func g13(string) string
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func h13(string, string) string
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// more incorrectly placed VARDEF.
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func f14() {
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x := g14()
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print(&x) // ERROR "live at call to printpointer: x"
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}
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func g14() string
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func f15() {
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var x string
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_ = &x
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x = g15() // ERROR "live at call to g15: x"
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print(x) // ERROR "live at call to printstring: x"
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}
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func g15() string
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// Checking that various temporaries do not persist or cause
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// ambiguously live values that must be zeroed.
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// The exact temporary names are inconsequential but we are
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// trying to check that there is only one at any given site,
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// and also that none show up in "ambiguously live" messages.
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var m map[string]int
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func f16() {
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if b {
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delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$"
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}
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delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$"
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delete(m, "hi") // ERROR "live at call to mapdelete: autotmp_[0-9]+$"
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}
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var m2s map[string]*byte
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var m2 map[[2]string]*byte
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var x2 [2]string
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var bp *byte
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func f17a() {
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// value temporary only
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if b {
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m2[x2] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+$"
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}
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m2[x2] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+$"
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m2[x2] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+$"
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}
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func f17b() {
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// key temporary only
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if b {
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m2s["x"] = bp // ERROR "live at call to mapassign1: autotmp_[0-9]+$"
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}
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m2s["x"] = bp // ERROR "live at call to mapassign1: autotmp_[0-9]+$"
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m2s["x"] = bp // ERROR "live at call to mapassign1: autotmp_[0-9]+$"
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}
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func f17c() {
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// key and value temporaries
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if b {
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m2s["x"] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$"
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}
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m2s["x"] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$"
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m2s["x"] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$"
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}
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func g18() [2]string
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func f18() {
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// key temporary for mapaccess.
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// temporary introduced by orderexpr.
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var z *byte
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if b {
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z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
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}
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z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
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z = m2[g18()] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
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print(z)
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}
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var ch chan *byte
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func f19() {
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// dest temporary for channel receive.
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var z *byte
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if b {
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z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$"
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}
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z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$"
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z = <-ch // ERROR "live at call to chanrecv1: autotmp_[0-9]+$"
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print(z)
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}
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func f20() {
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// src temporary for channel send
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if b {
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ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$"
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}
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ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$"
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ch <- nil // ERROR "live at call to chansend1: autotmp_[0-9]+$"
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}
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func f21() {
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// key temporary for mapaccess using array literal key.
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var z *byte
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if b {
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z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
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}
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z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
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z = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess1: autotmp_[0-9]+$"
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print(z)
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}
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func f23() {
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// key temporary for two-result map access using array literal key.
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var z *byte
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var ok bool
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if b {
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z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$"
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}
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z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$"
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z, ok = m2[[2]string{"x", "y"}] // ERROR "live at call to mapaccess2: autotmp_[0-9]+$"
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print(z, ok)
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}
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func f24() {
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// key temporary for map access using array literal key.
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// value temporary too.
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if b {
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m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$"
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}
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m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$"
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m2[[2]string{"x", "y"}] = nil // ERROR "live at call to mapassign1: autotmp_[0-9]+ autotmp_[0-9]+$"
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}
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