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// run
// Copyright 2023 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.
package main
import (
"math"
"reflect"
)
func main() {
for i := 0; i < 100; i++ {
f()
g()
}
}
func f() {
// Allocate map.
m := map[float64]int{}
// Fill to just before a growth trigger.
const N = 13 << 4 // 6.5 * 2 * 2^k
for i := 0; i < N; i++ {
m[math.NaN()] = i
}
// Trigger growth.
m[math.NaN()] = N
// Iterate through map.
i := 0
for range m {
if i == 6 {
// Partway through iteration, clear the map.
clear(m)
} else if i > 6 {
// If we advance to the next iteration, that's a bug.
panic("BAD")
}
i++
}
if len(m) != 0 {
panic("clear did not empty the map")
}
}
func g() {
// Allocate map.
m := map[float64]int{}
// Fill to just before a growth trigger.
const N = 13 << 4 // 6.5 * 2 * 2^k
for i := 0; i < N; i++ {
m[math.NaN()] = i
}
// Trigger growth.
m[math.NaN()] = N
// Iterate through map.
i := 0
v := reflect.ValueOf(m)
iter := v.MapRange()
for iter.Next() {
if i == 6 {
// Partway through iteration, clear the map.
v.Clear()
} else if i > 6 {
// If we advance to the next iteration, that's a bug.
panic("BAD")
}
i++
}
if v.Len() != 0 {
panic("clear did not empty the map")
}
}
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