I have corrected the patch I mentioned above, I have not uploaded it to my github yet though. But that is not what is causing that error. I have used the script on my home machine, work machine, and laptop with no issues. The only thing I am can think of I am doing different is that I use Alien Bob's openjdk-8 package. You have to have java8 for this build or disable java with --disable-java.
http://www.slackware.com/~alien/slackbuilds/openjdk/
You will also need to install gsoap and acpica
EDIT: I uploaded the new build with the corrected patch to github