Apparently it can be built only on FreeBSD 12 amd64.

11.3-i386: LLVM ERROR: out of memory
12.0-i386: parity-4c44772188702cce.parity.e8wnuwsj-cgu.11.rcgu.o: file not recognized: File format not recognized
11.3-amd64: parity-1a336ac89c32de09.parity.5withm3d-cgu.11.rcgu.o: file not recognized: File format not recognized