IPhone : IOS: No idea what is linkage message created from Xcode

I have a problem compiling and running the IOS application from Xcode. I received a message like this about linking files.

> Ld /Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Intermediates/Photo\ Collage.build/Debug-iphonesimulator/Photo\ Collage.build/Objects-normal/i386/Photo\ Collage\ -\ for\ Facebook normal i386
    cd "/Users/Simon/Desktop/Project/Projects/Photo Collage"
    export IPHONEOS_DEPLOYMENT_TARGET=4.3
    export PATH="/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
    /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
-arch i386 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator8.1.sdk
-L/Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Products/Debug-iphonesimulator
-F/Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Products/Debug-iphonesimulator
-F/Users/Simon/Desktop/Project/Tools/GoogleMobileAdsSdkiOS-7.0.0 -F/Users/Simon/Desktop/FacebookSDK -F/Users/Simon/Documents/FacebookSDK -filelist /Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Intermediates/Photo\ Collage.build/Debug-iphonesimulator/Photo\ Collage.build/Objects-normal/i386/Photo\ Collage\ -\ for\ Facebook.LinkFileList -Xlinker -objc_abi_version -Xlinker 2 -ObjC
-lsqlite3.0 -fobjc-link-runtime -Xlinker -no_implicit_dylibs -mios-simulator-version-min=4.3 -Xlinker -sectcreate -Xlinker __TEXT -Xlinker __entitlements -Xlinker /Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Intermediates/Photo\ Collage.build/Debug-iphonesimulator/Photo\ Collage.build/Photo\ Collage\ -\ for\ Facebook.app.xcent -framework FacebookSDK -framework AVFoundation -framework CoreTelephony -framework EventKit -framework EventKitUI -framework AudioToolbox -framework CoreGraphics -framework MessageUI -framework StoreKit -framework SystemConfiguration
-framework GoogleMobileAds -ledit.3.0 -weak_framework Accounts -weak_framework AdSupport -framework AssetsLibrary -framework CoreData -framework CoreLocation -framework iAd -framework MapKit -framework QuartzCore -weak_framework Social -framework UIKit -framework Foundation -Xlinker -dependency_info -Xlinker /Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Intermediates/Photo\ Collage.build/Debug-iphonesimulator/Photo\ Collage.build/Objects-normal/i386/Photo\ Collage\ -\ for\ Facebook_dependency_info.dat -o /Users/Simon/Library/Developer/Xcode/DerivedData/TopicShow-cemeiotytpxtvoblfwxyiihrfjqz/Build/Intermediates/Photo\ Collage.build/Debug-iphonesimulator/Photo\ Collage.build/Objects-normal/i386/Photo\ Collage\ -\ for\ Facebook

Undefined symbols for architecture i386:   "_OBJC_CLASS_$_GAI", referenced from:
      objc-class-ref in AppDelegate.o
      objc-class-ref in RootViewController.o   "_OBJC_CLASS_$_GAITrackedViewController", referenced from:
      _OBJC_CLASS_$_CategoryViewController in CategoryViewController.o
      _OBJC_CLASS_$_ImageViewController in ImageViewController.o
      _OBJC_CLASS_$_RootViewController in RootViewController.o   "_OBJC_METACLASS_$_GAITrackedViewController", referenced from:
      _OBJC_METACLASS_$_CategoryViewController in CategoryViewController.o
      _OBJC_METACLASS_$_ImageViewController in ImageViewController.o
      _OBJC_METACLASS_$_RootViewController in RootViewController.o ld: symbol(s) not found for architecture i386 clang: error: linker command failed with exit code 1 (use -v to see invocation)

Sorry i no the Question maybe confusing but i have no idea what these error related to only know it was a linking problem.

Please help