I just created one new cordova ios project via CLI, and i opened that project in Xcode 7.1 and while running on simulator am getting some error on mainViewController.xib, if
I'm in Xcode 7.3 and had the same issue after opening file in xCode 8.0. This worked for me:
Made a product/clean in Xcode, then quit Xcode and clean out all the content in ~/Library/Developer/Xcode/DerivedData manually.