After upgrading to Snow Leopard, Unity can no longer find FileMerge. It's really annoying because the UI to set the merge tool has only a combobox (which in my case is empty) so I can't set the path to FileMerge, which is installed and working. Is there a workaround for this? Where does Unity look for FileMerge? If I knew that I could create a symbolic link.
sudo /usr/bin/xcode-select -switch /Applications/Xcode.app
that should make it work
Try updating your XCode tools to 3.2.X. Snow Leopard wants the newer XCode set with an updated FileMerge. I had this problem on upgrade as well and this was the solution.
XCode - http://developer.apple.com/technologies/tools/xcode.html
Hmm I am on Mountain Lion now and I just installed XCode 4.5 and rebooted to no avail. I can open Xcode and File Merge just fine but Unity does not recognize File Merge.
I am going to reinstall Unity and see if that works.
If any insight would be appreciated.
bmcc