Why won't card.io build for running on an iPad Air?

Question

I fought this for a while today and wanted to post this hoping it might help someone else too.

I implemented the latest card.io SDK, 3.4.0 into an iOS 7 project. It builds fine for running on the simulator (which defeats the purpose) but will not build for my iPad Air. I keep getting 27 build errors like:

Undefined symbols for architecture arm64:
  "___cxa_end_catch", referenced from:
      icvReadSeq(CvFileStorage*, CvFileNode*) in libCardIO.a(persistence.o)
      std::__1::deque<char, std::__1::allocator<char> >::__add_back_capacity() in libCardIO.a(persistence.o)

I have followed their instructions to a tee yet cannot build.

Answer 1

All I had to do was add libstdc++.dylib as a "Linked Framework and Library" for my project then it worked great.

Answer 2

Dave from card.io here.

Please double-check that in your project's Build Settings (in the TARGETS section, not the PROJECTS section), your Other Linker Flags include -lc++.

[ETA: sorry, didn't see that you'd already posted your own solution!]