The other day Xcode was trying to tell me that it had “no rule to process a file”. It was a simple readme file that I had created on GitHub and subsequently pulled into my working copy.
Even though the project compiled fine, if there is a warning we can eliminate, we definitely should. Turns out it’s easy fix this problem.
Click on your project in the Project Navigator (the blue item on the left where you see all your project files), then head over to Build Phases. You’ll find a section called Compiled Sources. Expand it to see a selection of files.
Select the one Xcode is complaining about and remove it by clicking the little minus sign at the bottom.
Build the project again and see that warning disappear for good.