bdiff: avoid pointer arithmetic on void*
MSVC 2008 complains:
mercurial/cext/bdiff.c(106) : error C2036: 'void *' : unknown size
mercurial/cext/bdiff.c(107) : error C2036: 'void *' : unknown size
Maybe it's a gcc extension?
https://stackoverflow.com/questions/
37460579/error-c2036-void-unknown-size
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