For anyone stumbling over this and having trouble to build it, I had to figure out two things: 1. When building on x86_64 Debian, I had to install linux-libc-dev:i386 to get /usr/include/i386-linux-gnu/asm/unistd.h. I also had to adapt the include path to have it actually found. 2. If you see a segfault when running the executable, you likely need to remove -Wl,-Ttext,0 from the build command. At least on my system, it fixes the segfaults and now jonesforth runs as expected.