unsigned, with 'verbatim', they will be silently exported
and with 'warn', they will be exported, but you will see a warning.
+-M::
+-C::
+ Perform move and/or copy detection, as described in the
+ linkgit:git-diff[1] manual page, and use it to generate
+ rename and copy commands in the output dump.
++
+Note that earlier versions of this command did not complain and
+produced incorrect results if you gave these options.
+
--export-marks=<file>::
Dumps the internal marks table to <file> when complete.
Marks are written one per line as `:markid SHA-1`. Only marks