XCode: Undefined symbols for architecture arm64 error

Question

In my XCode 5 project I use RestKit for REST communication. Everything works fine with the simulators, but generating the ipa file, I get the following error:

Answer 1

This worked for me:

ios sdk 9.3

into your build setting of app.xcodeproj valid architecture: armv7 armv7s Build Active architecture : No

Clean and build , worked for me.