Well, this would break a lot of already set up automatic builds unexpectedly.  Obviously without having read this and actually doing the following "do not forgot to put actual tar.xz  in thirdparty/src while testing", it fails on all 4 of the computers I ran it on (just for verification purposes).  I did update "bld.sh" to mention the need to update nasm and cmake if needed on older computers and added that to the Manual to be checked in.  I finally updated nasm on Ubuntu16 and Fedora32 and seen how wasy it is if you just go to the releases directory of each, download the version you want, and compile it as provided in the instructions.