Fails with IO error if run from a disembodied git repo

Also generates error if run from a folder without a .git directory.

How to create a disembodied git repo:

git clone git://... myrepo
mkdir myclone
cd myclone
git init --other-git-dir=../myrepo/.git
git checkout .

Error output:

$ sudo bmake prod sync                                                                   
**** PRODUCTION APPLICATION ****
install -o www -g www -m 0755 -d /usr/local/g2planet/cisco_ec
install -o www -g www -m 0755 -d /usr/local/g2planet/cisco_ec/data
install -o www -g www -m 0755 -d /usr/local/g2planet/cisco_ec/data/attachments
Checking to make sure the database schema matches...
*** Error code 1 (ignored)
WEB_DIR=/usr/local/www/data/cisco_ec X_DIST_DIR=/usr/local/g2planet/cisco_ec TEMPLATE_REQUEST_CONF=TemplateRequest.ini WEB_USER=www WEB_GROUP=www DRY_RUN=0 G2ENV=prod MakefileSyncCommand
Global make sync tool


WARNING: This directory isn't a git repo, or git experienced an error. (Run git status for more info.) Are you sure you want to continue? (y/N) y

--- SYNCING DIST DIRECTORY ---
rsync: failed to open exclude file .git/info/exclude: Not a directory (20)
rsync error: error in file IO (code 11) at exclude.c(1179) [client=3.1.1]
*** Error code 1

Stop.
bmake: stopped in /home/dchurch/public_html/code/cisco-ec