5.3.2.4 Unconfigured Subdirectories

A subdirectory you wish not to configure in must appear in neither DIST_SUBDIRS nor SUBDIRS, regardless of how these variables are defined. If you need the subdirectory to be distributed, you must arrange for this to happen. For example:

• Always run ‘make dist’ in a configuration where all directories are known to appear in DIST_SUBDIRS
• Writing a dist-hook target to distribute these directories).

In a few packages, unconfigured directories are not even expected to be distributed.