I probably started skipping past this thread as soon as I saw the the initial response. It failed my 0.25-second test -- sorry.
Julius is right, though. cbfstool is built with your host compiler and the older versions of gcc don't like that patch.
As I am currently stuck on using 14.04 Ubuntu which has an old version
of GCC, I am curious what gcc versions are in use that folks are using
to build coreboot in standalone tree?
Although I wasn't "stuck", I didn't want to risk or take time switching away from 14.04 in the middle of an important project. I moved gcc forward only to 6.5.0 and no longer had the problem. The exact steps I used are long gone out of my history, but I probably used something like described here: https://gist.github.com/application2000/73fd6f4bf1be6600a2cf9f56315a2d91