Christopher M. Punches
5230ac8748
clean removes what the build produced and leaves the configured build system, so a build following it proceeds without reconfiguring. Deleting the build system from clean broke that: the target lives in the Makefile it removes, so nothing in the directory could drive a rebuild afterward. distclean empties the directory, build system included. It is terminal — the next step is `cmake -B <dir>` from outside — and it is what proves a change against a tree carrying no state from earlier runs.
