A quick update. Despite probably not having all the “bits” I continued to try a compilation of Xen 4.0.0 on Darwin. The result of a “make world”, after linking “darwin.mk” to “FreeBSD.mk” was an assembler syntax error in a file called “reloc.c” (copyright Citrix). Will check into that at the next session. Xen expects to be compiled on one of 10 architectures. Darwin is not one of them :-).