I\'m using Facebook SDK for iOS 4.6.0 and just today above error encountered after updating cocoapods to 0.38.2. I\'m not sure this error has anything to do with cocoapods.
I had the same issue. The problem appeared because, I was connecting both "ParseFacebookUtils" (which was loading "Facebook-iOS-SDK" (which is the deprecated version) and "FBSDKCoreKit" separately.
"Facebook-iOS-SDK" and "FBSDKCoreKit" both have "FBSDKMacros.h" which has different declarations of "FBSDK_NOT_DESIGNATED_INITIALIZER" and that is why message in XCode appear.
What I suggest, if "ParseFacebookUtils" is not in your podfile list, check which cocoaPod loading "Facebook-iOS-SDK" and try to update it with the newer version of that framework.
If "ParseFacebookUtils" is your case than easily change it to 'ParseFacebookUtilsV4'
And surely don't forget to run 'pod update' to make all changes active
Hope this helps.