About the changes in [9ef38b6b6d]:

At least the <tt>VAR != shell command</tt> is documented in BSD make, but the <tt>VAR :sh = shell command</tt> sure doesn't seem to be (although it does seem to work with BSD make).  In addition, neither syntax works with GNU make.  To get the equivalent with GNU make the syntax is <tt>VAR = $(shell shell command)</tt> instead.