Linker Error in iOS (duplicate symbols for architecture x86_64)

Question

I keep on getting the following error:

duplicate symbol _llvm.embedded.module in: /Users/name/Documents/FacebookSDKs-iOS-20150910/FBSDKCoreKit.framework/FBSDKCoreKit(FBSDKApplicationDelegate.o) /Users/name/Documents/FacebookSDKs-iOS-20150910/FBSDKCoreKit.framework/FBSDKCoreKit(FBSDKServerConfiguration.o) ld: 102 duplicate symbols for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) 

I've tried deleting the FBSDK and reinstalling, but that has not work. I also suspect that the fact that I'm bridging the framework into Swift may be the problem. My bridging header contains the following:

#ifndef EggCrush_Bridge_h #define EggCrush_Bridge_h  #import <FBSDKCoreKit/FBSDKCoreKit.h>  #endif 

My AppDelegate.swift file imports FBSDKCoreKit.
There are no other linker flags.
I'm running Xcode 6.3.2 and building a project for iOS 8.3

How to clear this error up?

Answer 1

If not mistaken, you are using the sdk which just released by Facebook at September 10th, 2015 which named as FacebookSDKs-iOS-20150910.zip. Try to use sdk that released at August 13th, 2015 which named as FacebookSDKs-iOS-20150813.zip and report to Facebook about the duplication problem if you can. Thank you.

Answer 2

This thread explains you must compile the Facebook 4.6.0 SDK in Xcode 7 to resolve the issue. After compiling in Xcode 7 it worked for me.

In the Facebook iOS SDK 4.6.0, App Thinning (Bitcode) support has been added and therefore it cannot be complied in Xcode versions lower than Xcode 7.0.