Hello Quinn I run into the same problem but above solution doesnt fixe the issue for me. I have other code which links to this static library and makes use of these categories and can not find the code and fails at runtime like this: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSTaggedPointerString intergerValueSupportingHex]: unrecognized selector sent to instance 0xa6bf563335312a11' in this case intergerValueSupportingHex is the category I defined in the universal library (ulib) which I use from another library. This is not a problem when building with dynamic libraries, only with static ones. And given the categories are code which is linked to the project, that code should have been found and corresponding symbols should be exported. Hence the supression of the warning will not solve the problem. The issue is not that we have a warning, the issue is that we have code which is not being found at runtime and thats very puzzling.