Go: Why does os.Getwd() sometimes fail with EOF

package main
import "os"
import "fmt"

func main() {
    _, err := os.Getwd()
    if err != nil {
        fmt.Println(err)
    }
}

This sometimes prints an error of EOF. Does anyone know why? There's usually some os.Chdir happening before, but that doesn't error out.

GOARCH="amd64"
GOBIN=""
GOCHAR="6"
GOEXE=""
GOGCCFLAGS="-g -O2 -fPIC -m64 -pthread -fno-common"
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"

go version go1.0.3

This is a bug in os.Getwd that causes it to return EOF as error when the working directory no longer exists, on platforms that don't support the getwd syscall. Here is a repeatable test case on OS X.

package main
import "os"
import "fmt"

const DIR = "/tmp/somedir"

func main() {
    os.Remove(DIR)
    if err := os.Mkdir(DIR, 0755); err != nil {
      fmt.Println(err)
      return
    }
    if err := os.Chdir(DIR); err != nil {
      fmt.Println(err)
      return
    }
    if err := os.Remove(DIR); err != nil {
      fmt.Println(err)
      return
    }
    wd, err := os.Getwd()
    fmt.Println("err:", err)
    fmt.Println("wd:", wd)
}

Output:

err: EOF
wd: