The backtrace in https://github.com/facebook/facebook-ios-sdk/issues/1374 https://github.com/facebook/facebook-ios-sdk/issues/1374 makes it sound like they pass

The backtrace in https://github.com/facebook/facebook-ios-sdk/issues/1374 https://github.com/facebook/facebook-ios-sdk/issues/1374 makes it sound like they passed a nil pointer to NSOrderedSet's initWithSet method, from inside FBSDKServerConfigurationManager's processLoadRequestResponse method. That makes it sound like a new version of the data provided by the server didn't have some field that old versions of the SDK expected, and the old code didn't catch that exception.