Since installing XCode 6 GM, it has been freezing and locking, showing the spinning wheel of death while I attempt to edit code that has syntax errors. Has anyone else seen
You should look if you have any imports missing in your bridging header file. Sometimes even commented out imports will cause this behaviour. For me it was commented out Pixate Freestyle Cocoa Pod. I had to remove pod completely from my project to stop SourceKitService from crashing.
https://stackoverflow.com/a/25173389/527539