// Regression: arena stack management under deep nesting with interface returns.

package main

import "fmt"

func nest0(s string) (r string) { r = s; return }

func nest1(s string) (r string) {
	var v fmt.Stringer = nest0(s)
	r = v.String()
	return
}

func nest2(s string) (r string) {
	var v fmt.Stringer = nest1(s)
	r = v.String()
	return
}

func nest3(s string) (r string) {
	var v fmt.Stringer = nest2(s)
	r = v.String()
	return
}

func main() {
	r := nest3("hello")
	println(r)
}