I had a pre-1.10 fork of clojurescript repo, I did a pull to get current latest from official clojurescript repo, and pushed to my fork to get it up-to-date. That didn't push tags by default and the build script started failing at git describe command.
The patch adds a simple check for this situation and continues with REVISION="0" if revision failed to be determined. For user's convenience it also prints a warning with a possible solution.
