Thanks @Etresoft... Everything is static in my project. Before XCFrameworks, the prev dev had managed to get a plain (static) framework to work with the cocoapods static lib dependencies by placing their header info in the Headers folder of the framework (the binary being fulfilled by cocoapods I guess). I'm not entirely sure why that worked... Is there no way to have static frameworks depending on other static frameworks?

I get the same thing after a build script that makes an xcframework action. But the build and framework create actions complete fine. This error just comes at the end. The file exists and perms are normal. Maybe an xcode bug?

Using use_frameworks! in the podfile does the trick!