DragonFlyBSD

On DragonFly master, for a previous recent build, if one does

make upgrade REMOVE_OPENSSL_FILES=yes

then updates to the latest master source, then

cd /usr/obj
mv usr usr.old
cd /usr/src
make buildworld

there seems a good chance one will encounter an error, really fast, such as:

===> bin/cpdup (bootstrap-tools)
/usr/obj/usr/src/btools_x86_64/usr/src/bin/cpdup created for /usr/src/bin/cpdup
rm -f .depend

.depend

mkdep -f .depend -a -std=gnu99 /usr/src/bin/cpdup/cpdup.c /usr/src/bin/cpdup/hcproto.c /usr/src/bin/cpdup/hclink.c /usr/src/bin/cpdup/misc.c /usr/src/bin/cpdup/fsmid.c /usr/src/bin/cpdup/md5.c
In file included from /usr/include/md5.h:41:0,
from /usr/src/bin/cpdup/cpdup.h:28,
from /usr/src/bin/cpdup/cpdup.c:58:
/usr/include/sys/md5.h:45:25: fatal error: openssl/md5.h: No such file or directory
compilation terminated.

It seems to me that cpdup.c includes "cpdup.h" which in turn includes <md5.h> if NOMD5 is undefined,
which in turn includes <sys/md5.h>, which in turn includes <openssl/md5.h>,
which after make upgrade REMOVE_OPENSSL_FILES doesn't exist anymore.