HEAD build failure on win32 mingw

Hello,

HEAD is failed to be built on win32 mingw.
It requires manual 'mkdir man7' or so.

Are there any changes in build process?
Or am I missing something required to build?

----
$ make
/bin/sh.exe: man7/.timestamp: No such file or directory

$ mkdir doc/man7            <- HERE
$ make
(succeeded to build)

$ make install
../config/install-sh: man7/*.7 does not exist.

$ touch doc/man7/dummy.7    <- HERE
$ make install
(succeeded to install)

----

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center