I started getting this error from 0.138 for some reason. Not to mention that I'd already built a version of WolfMAME 0.138 before that (without any modification first, so that I don't have to wait so long to compile while working on it, my Windows PC is rather old). So what I did, was simply rename the folder containing the source, and the error disappeared. Just to be sure, I renamed the folder back to what it was, and the error returned. So shortening the name of the folder containing the source might help.