Failure building current 4.5 snapshot on Cygwin

[Angelo Graziosi <angelo dot graziosi at alice dot it>]

I want to flag the following failure I have seen on Cygwin 1.5 trying to 
build current 4.5-20090625 gcc snapshot:

-------------------------------------------
[...]
make[2]: Entering directory `/tmp/build'
Configuring stage 2 in ./intl
Configuring stage 2 in ./libiberty
Configuring stage 2 in ./libdecnumber
configure: creating cache ./config.cache
configure: creating cache ./config.cache
checking whether to enable maintainer-specific portions of Makefiles... no
checking for makeinfo... makeinfo --split-size=5000000 --split-size=5000000
checking whether make sets $(MAKE)... checking for perl... perl
yes
checking for a BSD-compatible install... /usr/bin/install -c
checking whether NLS is requested... yes
checking build system type... checking for msgfmt... configure: creating 
cache ./config.cache
/usr/bin/msgfmt
checking for gmsgfmt... /usr/bin/msgfmt
checking for xgettext... i686-pc-cygwin
checking whether make sets $(MAKE)... /usr/bin/xgettext
checking for msgmerge... checking host system type... /usr/bin/msgmerge
yes
checking for i686-pc-cygwin-gcc...  /tmp/build/./prev-gcc/xgcc 
-B/tmp/build/./prev-gcc/ -B/usr/local/gfortran/i686-pc-cygwin/bin/ 
-B/usr/local/gfortran/i686-pc-cygwin/bin/ 
-B/usr/local/gfortran/i686-pc-cygwin/lib/ -isystem 
/usr/local/gfortran/i686-pc-cygwin/include -isystem 
/usr/local/gfortran/i686-pc-cygwin/sys-include
checking for i686-pc-cygwin-gcc...  /tmp/build/./prev-gcc/xgcc 
-B/tmp/build/./prev-gcc/ -B/usr/local/gfortran/i686-pc-cygwin/bin/ 
-B/usr/local/gfortran/i686-pc-cygwin/bin/ 
-B/usr/local/gfortran/i686-pc-cygwin/lib/ -isystem 
/usr/local/gfortran/i686-pc-cygwin/include -isystem 
/usr/local/gfortran/i686-pc-cygwin/sys-include
i686-pc-cygwin
checking for i686-pc-cygwin-ar... ar
checking for i686-pc-cygwin-ranlib... ranlib
checking for i686-pc-cygwin-gcc...  /tmp/build/./prev-gcc/xgcc 
-B/tmp/build/./prev-gcc/ -B/usr/local/gfortran/i686-pc-cygwin/bin/ 
-B/usr/local/gfortran/i686-pc-cygwin/bin/ 
-B/usr/local/gfortran/i686-pc-cygwin/lib/ -isystem 
/usr/local/gfortran/i686-pc-cygwin/include -isystem 
/usr/local/gfortran/i686-pc-cygwin/sys-include
checking for C compiler default output file name... checking for C 
compiler default output file name... a.exe
checking whether the C compiler works... a.exe
checking whether the C compiler works... configure: error: in 
`/tmp/build/intl':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.
See `config.log' for more details.
checking for C compiler default output file name... configure: error: in 
`/tmp/build/libdecnumber':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.
See `config.log' for more details.
make[2]: *** [configure-stage2-libdecnumber] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: *** [configure-stage2-intl] Error 1
a.exe
checking whether the C compiler works... configure: error: in 
`/tmp/build/libiberty':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.
See `config.log' for more details.
make[2]: *** [configure-stage2-libiberty] Error 1
make[2]: Leaving directory `/tmp/build'
make[1]: *** [stage2-bubble] Error 2
make[1]: Leaving directory `/tmp/build'
make: *** [all] Error 2
-------------------------------------------

I have configured with:

===================================
CC='gcc-4' CXX='g++-4' CPP='cpp-4' ${gcc_dir}/configure 
--prefix="${prefix_dir}" \
        --exec-prefix="${eprefix_dir}" \
	--sysconfdir="${sysconf_dir}" \
	--libdir="${lib_dir}" \
	--libexecdir="${libexec_dir}" \
	--mandir="${man_dir}" \
	--infodir="${info_dir}" \
	--program-suffix="${suffix}" \
	--enable-languages=c,c++,fortran \
	--enable-bootstrap \
	--enable-decimal-float=bid \
	--enable-libgomp \
	--enable-threads \
	--enable-sjlj-exceptions \
	--enable-version-specific-runtime-libs \
	--enable-nls \
	--enable-checking=release \
	--disable-fixed-point \
	--disable-libmudflap \
	--disable-shared \
	--disable-win32-registry \
	--with-arch=i686 \
	--with-system-zlib \
	--with-tune=generic \
        --without-included-gettext \
	--without-x || return 1
===================================

The source comes from the following files:

gcc-core-4.5-20090625.tar.bz2
gcc-fortran-4.5-20090625.tar.bz2
gcc-g++-4.5-20090625.tar.bz2


I have tried using 'make -j2[or -j4]'


Cheers,
Angelo.