Pierre Lebeaupin on building with third party libs for iOS 6:
Word on the street is that some people have trouble doing so, however; apparently the GM for Xcode 4.5, which Apple mandates be used for submitting apps that use iOS 6 features, has added out of the blue a new architecture variant called ARMv7s, and it’s causing link errors when building this slice for app projects using third-party libraries, as those do not have an ARMv7s slice (bit of the same issue than for ARMv6-only libraries, except more widespread apparently). This is causing a rush to source updated version of these dependencies or even hackish instructions (no link, because too risky) to modify the libraries to craft an ARMv7s slice.
Check his post out for the simple fix in Xcode that will hold you over until your third party dependencies can link with an ARMv7s build. Or, your know, use a lib with the source instead1.
Of course, even if you did build your externals from source, you don’t have the right device to test in on. Yet. :)↩
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