* Jonas Smedegaard <dr@jones.dk>, 2015-07-23, 21:40:
One mistake boost makes is using ":=" instead of plain "=". Contrary to popular belief, the former almost always causes more evaluation of $(shell) stuff, specially when dh is involved.Could you elaborate on that?
dpkg-buildpackage -B will run debian/rules 4 times: once to determine if build-arch exist, and once for every target: clean, build(-arch), binary-arch.
dh adds even more debian/rules invocations. It runs it once every target (clean, build(-arch), binary-arch), and once for every override.
So your ":=" variable will be evaluated 4 times, or 7+N times if you use dh.
"=" variables will be evaluated only when they are used, which is less than 4 or 7+N in most cases.
-- Jakub Wilk