Just a sample iOS project that reproduces the diamond problem we have when a package with 2 dynamic products that depends each other are embedded in the App producing the following error:
Swift package target 'SPM' is linked as a static library by 'ReallySimpleApp' and 'SPM', but cannot be built dynamically because there is a package product with the same name.
More info:
Go to the target - Build Settings - User Defined and change DISABLE_DIAMOND_PROBLEM_DIAGNOSTIC to YES.