Bootstrap broken on Cygwin

[Angelo Graziosi <angelo.graziosi@alice.it>]

After recent changes [*] to 'strftime', the bootstrap of trunk is broken 
on Cygwin. For example, with rev. 102432:

[...]
gcc -c  -Demacs -DHAVE_CONFIG_H  -I. -I/tmp/emacs/src   -D_REENTRANT 
-I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/include/atk-1.0 
-I/usr/include/cairo -I/usr/include/pango-1.0 
-I/usr/include/gio-unix-2.0/ -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include -I/usr/include/pixman-1 
-I/usr/include/freetype2 -I/usr/include/libpng12 
-I/usr/include/freetype2     -D_REENTRANT -I/usr/include/librsvg-2 
-I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include 
-I/usr/include/gtk-2.0 -I/usr/include/cairo -I/usr/include/pixman-1 
-I/usr/include/freetype2 -I/usr/include/libpng12   -fopenmp 
-I/usr/include/ImageMagick   -I/usr/include/libxml2 
-I/usr/include/dbus-1.0 -I/usr/lib/dbus-1.0/include   -DORBIT2=1 
-D_REENTRANT -I/usr/include/gconf/2 -I/usr/include/orbit-2.0 
-I/usr/include/dbus-1.0 -I/usr/lib/dbus-1.0/include 
-I/usr/include/glib-2.0 -I/usr/lib/glib-2.0/include       -MMD -MF 
deps/strftime.d   -Wimplicit-function-declaration -Wold-style-definition 
-Wdeclaration-after-statement -Wno-pointer-sign  -g -O2 
/tmp/emacs/src/strftime.c
/tmp/emacs/src/strftime.c:58: warning: ‘_tzname’ redeclared without 
dllimport attribute: previous dllimport ignored
/tmp/emacs/src/strftime.c: In function ‘nstrftime’:
/tmp/emacs/src/strftime.c:469: warning: implicit declaration of function 
‘_strftime_copytm’
/tmp/emacs/src/strftime.c: At top level:
/tmp/emacs/src/strftime.c:483: error: conflicting types for 
‘_strftime_copytm’
/tmp/emacs/src/strftime.c:469: error: previous implicit declaration of 
‘_strftime_copytm’ was here
make[1]: *** [strftime.o] Error 1
make[1]: Leaving directory `/tmp/emacs/Work/src'
make: *** [src] Error 2

Ciao,
Angelo.

---
[*]
2010-11-16  Dan Nicolaescu  <dann@ics.uci.edu>

         * strftime.c (LOCALE_PARAM_DECL): Update for standard C.
           [...]