I have just integrated the MarketingCloudSDK (5.2.1) via CocoaPods to an iOS app and I am facing a duplicate symbol error. Someone already had the same issue posted to the apple forum:
https://forums.developer.apple.com/thread/105532 but never got a reply.
All our pods are statically linked. The App is pure Objective C. We added for the App "Other Linker Flags": -all_load for good reasons (which is actually causing the trouble).
In our app we have "Code coverage" set to "Gather coverage" for all targets. If I turn it off, it is working, but our CI should really run with code coverage.
Is it possible that the sdk was build with CLANG_ENABLE_CODE_COVERAGE? I believe it is the corresponding flag.
Or some other profiling flags, i.e. -fprofile-instr-generate which would be rejected by Apple: https://developer.apple.com/library/archive/qa/qa1964/_index.html