[PATCH] PR23799 - sprint_ustack() always returns empty string values

[Yichun Zhang]

Hello!

On Fri, Oct 19, 2018 at 3:05 PM Yichun Zhang (agentzh)
<yichun@openresty.com> wrote:
>
> The tapset function sprint_ustack() forgot to actually return
> the computed string value. Alas.

Just committed to master with the approval of fche.

Best,
Yichun