Don't know why anyone's modded you down. I was thinking that either the interpreter, e.g. ruby, or the script itself already returned a non-zero exit status an

Don't know why anyone's modded you down. I was thinking that either the interpreter, e.g. ruby, or the script itself already returned a non-zero exit status and the makefile detected that. That doesn't cause make to remove the target. $ make foo false >foo make: *** [foo] Error 1 $ make foo make: `foo' is up to date. $ I suppose they could do "cmd foo >bar || rm bar" instead of the mv I suggested. But that causes no bar to exist whereas the mv leaves the pre-build one behind.