When trying to recompile dosemu (0.99.13-5, as found in powertools/6.2), as86 (0.15.0-2) hangs on the file fossil.s, and creates an keeps adding to fossil.s.out until the disk is full. 0.14 didn't have this bug (the build system is still running 0.14 fortunately).
everything seems to work for powertools 7.0 (and dosemu-1.0)...