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
#if no-windows no-osx
$ mkdir -p xdgconf/hg
$ echo '[ui]' > xdgconf/hg/hgrc
$ echo 'username = foobar' >> xdgconf/hg/hgrc
$ XDG_CONFIG_HOME="`pwd`/xdgconf" ; export XDG_CONFIG_HOME
$ unset HGRCPATH
$ hg config ui.username 2>/dev/null
foobar
#endif