The phobos2 files were pretty much outdated and did not allow for compilation on PowerPC or cross targeting it.
replaced Clong_d which seems a phobos1 relic with __builtin_Clong as used in ldfuncs-darwin.
added the required jmp_buf definitions for ppc to the druntime
added threadasm.o to the makefile and updated the asm to use register indices instead of names, thus not requiring kernel sources or ppc gas specific -mregisters
With these patches I've successfully run the sample under