Re: git clean --exclude broken?

Todd Rinaldo [off-list ref] writes:

I think I have found a new bug in 1.7.5:

My quick check indicates 1.7.3 behaves the same way, and 1.7.2.5 didn't
have --exclude option, so this does not seem to be anything particularly
new in the 1.7.5 release.

# The problem (Why is foo/ removed?)
$>git clean -dXf --exclude=/foo
Removing bar/
Removing foo/

Why is this command line giving -X that tells us not to use the ignore
rules, and --exclude option at the same time?