问题:

I seem to have hit a bug because everytime I open my project it tries to index the files but never gets done. When indexing I can see swift and SourceKitService high up in the Activity Monitor.

回答1:

There is a bug in the Swift compiler / indexer. Some line or lines in your code is giving it difficulty. You will have to edit your code with some other text editor to comment out the offending line(s) before you will be able to open that project with Xcode. If you have no clue what the problem is, comment out all your code. Once you have the project open, you can start bringing back code little by little until the rise in CPU activity tells you that you've found the problem.

回答2:

I had same issue with Xcode 6. The system got hang every time when I open the Xcode. Finally I removed the Xcode from Application and reinstalled, that fixed my problem.To uninstall Xcode 4.3 and later, all you need to do is go to /Applications/ and delete the Xcode Application.