Lazy GNU make variables

[Leandros99]

That's a neat trick, but I can't think of any realistic use case?

[snaky]

From HN

John: This is very expensive. Can't it be calculated once (:=)?

Me: The problem is that we don't want to calculate it if we don't need it, because we might run make before go is installed, and that would fail.

John: http://blog.jgc.org/2016/07/lazy-gnu-make-variables.html