Вышла версия cmake 3.9.2. А в Changelog'е написано про сабжевый баг:
* On macOS, the default application bundle ``Info.plist`` file no longer
enables Hi-DPI support as it did in 3.9.0 and 3.9.1. The change had
to be reverted because it broke iOS applications.
* The Xcode generator no longer adds "outputPaths" to custom script
build phases as it did in 3.9.0 and 3.9.1. This was added in an
attempt to support Xcode 9's new build system, but broke incremental
rebuilds for both the old and new Xcode build systems.