Commit 1081 set the value of addrLast to 0w0-0w1 but this causes an arbitrary precision trap in Word.toInt.  Changed to the maximum allocation size in bytes to avoid this.
Commit 1081 set the value of addrLast to 0w0-0w1 but this causes an arbitrary precision trap in Word.toInt.  Changed to the maximum allocation size in bytes to avoid this.

git-svn-id: 98787b36aaefbae4b30fa755be920954cd25e1e4@1099 ae7d391e-3f74-4a2b-a0db-a8776840fd2a

polyml/polyml,dcjm/polyml,dcjm/polyml,polyml/polyml,mn200/polyml,mn200/polyml,polyml/polyml,dcjm/polyml,dcjm/polyml,mn200/polyml,polyml/polyml,mn200/polyml