Unexpected behavior when closing io.PipeReader

[spongehah]

The code provided below is a minimal reproduction of this issue.

package main

import (
	"fmt"
	"io"
	"time"
)

func main() {
	reader, writer := io.Pipe()

	go func() {
		println("goroutine start")
		_, err := writer.Write([]byte("hello"))
		if err != nil {
			fmt.Println(err)
			writer.Close()
		}
		println("goroutine end")
	}()

	//c.Usleep(2 * 1000 * 1000)
	time.Sleep(2 * time.Second)
	reader.Close()
	//c.Usleep(2 * 1000 * 1000)
	time.Sleep(2 * time.Second)
}

Unexpected output: (llgo)

llgo run .
goroutine start

Expected output(go):

go run .
goroutine start
io: read/write on closed pipe
goroutine end