80c80
< system = System(tester = tester, physmem = SimpleMemory())
---
> system = System(tester = tester, physmem = SimpleMemory(null = True))
107,112d106
< #
< # Ruby doesn't need the backing image of memory when running with
< # the tester.
< #
< ruby_port.access_phys_mem = False
<