New build system - cannot clean from the command line

xcodebuild -configuration Release clean
xcodebuild -configuration Release clean
note: Using new build system
error: Could not delete / because it was not created by the build system.
error: Could not delete / because it was not created by the build system.
error: Could not delete / because it was not created by the build system.
error: Could not delete / because it was not created by the build system.

I wonder if this is a problem for anyone else?

I’m seeing the same thing here. The error message displays the absolute path to the Builds/MacOSX/build folder inside my project folder.

We were seeing this as well, but it seems that updating Xcode → Preferences → Locations → Advanced → Build Locations to “Unique” solves it.

I’m also seeing the problem when I try to clean Projucer.xcodeproj.
Build Locations were already set to “Unique” and I don’t have any problem cleaning my plugin projects…