我该如何修复zsh：无法识别的修饰符`P'

Question

在Ubuntu 14.04上执行以下操作时：

pek-ygao-d1% bad_pwd="/${(l:16000:: :):-}"
pek-ygao-d1% print ${bad_pwd:P}
zsh: unrecognized modifier `P'
And the version is zsh 5.4.2-dev-0 (x86_64-unknown-linux-gnu).

请告诉我如何才能完成这项工作？