I believe the warning is related to this paragraph in the Xcode 11.4 Release Notes: "Xcode now validates the deployment target of test bundle targets, and skips running any tests that are incompatible with the selected run destination. Some targets may require a change to their minimum deployment target build setting to continue to run on older run destinations. (39775813)" https://developer.apple.com/documentation/xcode-release-notes/xcode-11_4-release-notes As soon as I changed the Deployment Target on the *XCode project* file, the warning disappeared.