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// run
// Copyright 2017 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 to make sure RHS is evaluated before map insert is started.
// The RHS panics in all of these cases.
package main
import "fmt"
func main() {
for i, f := range []func(map[int]int){
f0, f1, f2, f3, f4, f5, f6, f7, f8,
} {
m := map[int]int{}
func() { // wrapper to scope the defer.
defer func() {
recover()
}()
f(m) // Will panic. Shouldn't modify m.
fmt.Printf("RHS didn't panic, case f%d\n", i)
}()
if len(m) != 0 {
fmt.Printf("map insert happened, case f%d\n", i)
}
}
// Append slice.
for i, f := range []func(map[int][]int){
fa0, fa1, fa2, fa3,
} {
m := map[int][]int{}
func() { // wrapper to scope the defer.
defer func() {
recover()
}()
f(m) // Will panic. Shouldn't modify m.
fmt.Printf("RHS didn't panic, case fa%d\n", i)
}()
if len(m) != 0 {
fmt.Printf("map insert happened, case fa%d\n", i)
}
}
}
func f0(m map[int]int) {
var p *int
m[0] = *p
}
func f1(m map[int]int) {
var p *int
m[0] += *p
}
func f2(m map[int]int) {
var p *int
sink, m[0] = sink, *p
}
func f3(m map[int]int) {
var p *chan int
m[0], sink = <-(*p)
}
func f4(m map[int]int) {
var p *interface{}
m[0], sink = (*p).(int)
}
func f5(m map[int]int) {
var p *map[int]int
m[0], sink = (*p)[0]
}
func f6(m map[int]int) {
var z int
m[0] /= z
}
func f7(m map[int]int) {
var a []int
m[0] = a[0]
}
func f8(m map[int]int) {
var z int
m[0] %= z
}
func fa0(m map[int][]int) {
var p *int
m[0] = append(m[0], *p)
}
func fa1(m map[int][]int) {
var p *int
sink, m[0] = !sink, append(m[0], *p)
}
func fa2(m map[int][]int) {
var p *int
m[0], _ = append(m[0], 0), *p
}
func fa3(m map[int][]int) {
// OSLICE has similar in-place-reassignment
// optimizations as OAPPEND, but we need to make sure
// to *not* optimize them, because we can't guarantee
// the slice indices are within bounds.
m[0] = m[0][:1]
}
var sink bool
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