Xcode tip: kill the index

Just now Xcode crashed while in the background. I immediately checked for project.pbxproj corruption but Git showed me that the file was unchanged. Each time I tried to open the project Xcode would beachball for a few seconds and then crash, 100% reproducibly.

The tip is this: Xcode 3 creates a new folder in your SRCROOT named index whose data could possibly become corrupt or unpalatable to Xcode in some mysterious way; if your copy starts crashing it’s worth blowing away that folder and seeing what happens. Cured the crashes instantly.