--work-tree does not work for git-stash

[Allen Li <vianchielfaura@xxxxxxxxx>]

$ git --version
git version 2.14.1.581

This does not work:

$ git --git-dir ~/foo/.git --work-tree ~/foo stash create
fatal: /usr/lib/git-core/git-stash cannot be used without a working tree.

This does:

$ git --git-dir ~/foo/.git --work-tree ~/foo -C ~/foo stash create

I found a description of the bug here:

https://stackoverflow.com/a/5863555