This program's heap grows without bound in the Go 1.4 beta. Keith, can you take a look?

package main

import (
    "runtime"
    "sync"
)

func main() {
    runtime.GOMAXPROCS(4)

    var mu sync.Mutex
    var cond sync.Cond
    cond.L = &mu
    go func() {
        for {
            cond.Signal()
        }
    }()
    mu.Lock()
    for {
        cond.Wait()
    }
}