Weird error from pkg-fallout

[Montgomery-Smith, Stephen]

I am getting messages from pkg-fallout saying that the port cad/gmsh
does not build.  See here:

http://beefy3.nyi.freebsd.org/data/head-i386-default/p416942_s301941/logs/gmsh-2.12.0.log

The main error it seems to report is this:
*** Bad machine code: Using an undefined physical register ***

Does this mean that cad/gmsh does not build on FreeBSD-CURRENT?  Or is
this error some strange mismatch created by a jailed environment?