Undefined symbols for architecture arm64

I solved this problem by setting that:

ARCHS = armv7 armv7s

VALID_ARCHS = armv6 armv7 armv7s arm64

The issue is that the cocoapods have not been built for arm64 architecture yet thus they cannot be linked when you build them. Likely you cannot use those packages until they are updated and use that architecture. You can fix the linker error by going to project -> target (your project name) -> build settings and change architectures to standard architectures (armv7, armv7s), and valid architectures to armv7, armv7s.

Note though, this means you won't get the full power of the 64 bit processor. You said you are building for the 5s, so there may be some reason you need this. If you for some reason absolutely need that power (perhaps you are building a game), and desperately need those files, you could submit a pull request and then recompile the project to arm64 by setting those same fields to arm64 in the files you pulled from the open source projects. But, unless you really need these files to be 64 bit compatible, that seems like a bit of overkill for now.

EDIT: Some people also reported that setting Build For Active Architectures to YES was also necessary to solve this problem.

As of 2014-04-28 the setting should look something like this:

I ran into the same/similar issue implementing AVPictureInPictureController and the issue was that I wasn't linking the AVKit framework in my project.

The error message was:

Undefined symbols for architecture armv7:
   "_OBJC_CLASS_$_AVPictureInPictureController", referenced from:
       objc-class-ref in yourTarget.a(yourObject.o)
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

The Solution:

1. Go to your Project
2. Select your Target
3. Then, go to Build Phases
4. Open Link Binary With Libraries
5. Finally, just add + the AVKit framework / any other framework.

Hopefully this helps someone else running into a similar issue I had.

If your Architectures and Valid Architectures are all right, you may check whether you have added $(inherited) , which will add linker flags generated in pods, to Other Linker Flags as below: