New in version 3.10.

Specify a list of text labels associated with a directory and all of its subdirectories. This is equivalent to setting the LABELS target property and the LABELS test property on all targets and tests in the current directory and subdirectories. Note: Launchers must enabled to propagate labels to targets.

The CMAKE_DIRECTORY_LABELS variable can be used to initialize this property.

The list is reported in dashboard submissions.