--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2013-01-16  Paul Eggert  <eggert@cs.ucla.edu>
 
+	unistd: port to recent mingw
+	* lib/unistd.in.h: Remove special invocation convention for mingw,
+	which breaks for the latest mingw version.  See John W. Eaton in
+	<http://lists.gnu.org/archive/html/bug-gnulib/2013-01/msg00100.html>.
+
 	largefile: port better to Mac OS X 10.5
 	This patch is backported from Autoconf git.
 	* m4/largefile.m4 (AC_SYS_LARGEFILE): Use AC_DEFINE, not

--- a/lib/unistd.in.h
+++ b/lib/unistd.in.h
@@ -14,29 +14,13 @@
    You should have received a copy of the GNU General Public License
    along with this program; if not, see <http://www.gnu.org/licenses/>.  */
 
+#ifndef _@GUARD_PREFIX@_UNISTD_H
+
 #if __GNUC__ >= 3
 @PRAGMA_SYSTEM_HEADER@
 #endif
 @PRAGMA_COLUMNS@
 
-/* Special invocation convention:
-   - On mingw, several headers, including <winsock2.h>, include <unistd.h>,
-     but we need to ensure that both the system <unistd.h> and <winsock2.h>
-     are completely included before we replace gethostname.  */
-#if @GNULIB_GETHOSTNAME@ && @UNISTD_H_HAVE_WINSOCK2_H@ \
-  && !defined _GL_WINSOCK2_H_WITNESS && defined _WINSOCK2_H
-/* <unistd.h> is being indirectly included for the first time from
-   <winsock2.h>; avoid declaring any overrides.  */
-# if @HAVE_UNISTD_H@
-#  @INCLUDE_NEXT@ @NEXT_UNISTD_H@
-# else
-#  error unexpected; report this to bug-gnulib@gnu.org
-# endif
-# define _GL_WINSOCK2_H_WITNESS
-
-/* Normal invocation.  */
-#elif !defined _@GUARD_PREFIX@_UNISTD_H
-
 /* The include_next requires a split double-inclusion guard.  */
 #if @HAVE_UNISTD_H@
 # @INCLUDE_NEXT@ @NEXT_UNISTD_H@