Hi all!
I have trouble with building GCC-4.7.2 with latest mingw-w64 from trunk.
My configure line is:
configure --host=i686-w64-mingw32 --build=i686-w64-mingw32 --target=i686-w64-mingw32 --prefix=/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix --with-sysroot=/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix --enable-shared --enable-static --enable-targets=all --enable-multilib --enable-languages=c,c++,fortran,lto --enable-libstdcxx-time=yes --enable-threads=posix --enable-libgomp --enable-lto --enable-graphite --enable-cloog-backend=isl --enable-checking=release --enable-fully-dynamic-string --enable-version-specific-runtime-libs --enable-sjlj-exceptions --disable-ppl-version-check --disable-cloog-version-check --disable-libstdcxx-pch --disable-libstdcxx-debug --disable-bootstrap --disable-rpath --disable-win32-registry --disable-nls --disable-werror --disable-symvers --with-gnu-as --with-gnu-ld --with-arch-32=i686 --with-arch-64=nocona --with-tune-32=generic --with-tune-64=core2 --with-host-libstdcxx=-static -lstdc++ --with-libiconv --with-system-zlib --with-gmp=/temp/mingw-prereq/i686-w64-mingw32-static --with-mpfr=/temp/mingw-prereq/i686-w64-mingw32-static --with-mpc=/temp/mingw-prereq/i686-w64-mingw32-static --with-ppl=/temp/mingw-prereq/i686-w64-mingw32-static --with-cloog=/temp/mingw-prereq/i686-w64-mingw32-static CFLAGS=-O2 -pipe -fomit-frame-pointer -I/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/include -I/temp/x32-4.7.2-release-posix-sjlj-rev5/libs/include -I/temp/mingw-prereq/i686-w64-mingw32-static/include CXXFLAGS=-O2 -pipe -fomit-frame-pointer CPPFLAGS= LDFLAGS=-pipe -L/temp/x32-4.7.2-release-posix-sjlj-rev5/libs/lib -L/temp/mingw-prereq/i686-w64-mingw32-static/lib -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/lib -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/opt/lib

During build I have next error:

libtool: compile:  /temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/xgcc -shared-libgcc -B/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc -nostdinc++ -L/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/src -L/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/src/.libs -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/lib -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/include -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/bin/ -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib/ -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/sys-include -I/temp/mingw-sources/gcc-4.7.2/libstdc++-v3/../libgcc -I/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/include/i686-w64-mingw32 -I/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/include -I/temp/mingw-sources/gcc-4.7.2/libstdc++-v3/libsupc++ -fno-implicit-templates -Wall -Wextra -Wwrite-strings -Wcast-qual -Wabi -fdiagnostics-show-location=once -ffunction-sections -fdata-sections -frandom-seed=math_stubs_float.lo -g -O2 -pipe -fomit-frame-pointer -c ../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc -o math_stubs_float.o
../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc: In function 'float fabsf(float)':
../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc:35:3: error: redefinition of 'float fabsf(float)'
In file included from C:/gccbuild/msys/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/include/cmath:46:0,
                 from ../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc:25:
C:/gccbuild/msys/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include/math.h:163:30: error: 'float fabsf(float)' previously defined here
../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc: In function 'float expf(float)':
../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc:99:3: error: redefinition of 'float expf(float)'
In file included from C:/gccbuild/msys/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/include/cmath:46:0,
                 from ../../../../../../../mingw-sources/gcc-4.7.2/libstdc++-v3/src/c++98/math_stubs_float.cc:25:
C:/gccbuild/msys/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include/math.h:588:22: error: 'float expf(float)' previously defined here
libtool: compile:  /temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/xgcc -B/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/ -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/lib -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/include -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/bin/ -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib/ -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/sys-include -DHAVE_CONFIG_H -I. -I../../../../../mingw-sources/gcc-4.7.2/libgfortran -iquote../../../../../mingw-sources/gcc-4.7.2/libgfortran/io -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../gcc -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../gcc/config -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../libquadmath -I../.././gcc -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../libgcc -I../libgcc -std=gnu99 -Wall -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -Wextra -Wwrite-strings -fcx-fortran-rules -ffunction-sections -fdata-sections -g -O2 -pipe -fomit-frame-pointer -I/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/include -I/temp/x32-4.7.2-release-posix-sjlj-rev5/libs/include -I/temp/mingw-prereq/i686-w64-mingw32-static/include -MT maxloc0_8_i8.lo -MD -MP -MF .deps/maxloc0_8_i8.Tpo -c ../../../../../mingw-sources/gcc-4.7.2/libgfortran/generated/maxloc0_8_i8.c  -DDLL_EXPORT -DPIC -o .libs/maxloc0_8_i8.o
libtool: compile:  /temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/xgcc -B/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/ -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/lib -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/include -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/bin/ -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib/ -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/sys-include -DHAVE_CONFIG_H -I. -I../../../../../mingw-sources/gcc-4.7.2/libgfortran -iquote../../../../../mingw-sources/gcc-4.7.2/libgfortran/io -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../gcc -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../gcc/config -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../libquadmath -I../.././gcc -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../libgcc -I../libgcc -std=gnu99 -Wall -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -Wextra -Wwrite-strings -fcx-fortran-rules -ffunction-sections -fdata-sections -g -O2 -pipe -fomit-frame-pointer -I/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/include -I/temp/x32-4.7.2-release-posix-sjlj-rev5/libs/include -I/temp/mingw-prereq/i686-w64-mingw32-static/include -MT maxloc0_16_i8.lo -MD -MP -MF .deps/maxloc0_16_i8.Tpo -c ../../../../../mingw-sources/gcc-4.7.2/libgfortran/generated/maxloc0_16_i8.c  -DDLL_EXPORT -DPIC -o .libs/maxloc0_16_i8.o
libtool: compile:  /temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/xgcc -B/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/./gcc/ -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib -L/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/lib -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/mingw/include -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/bin/ -B/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/lib/ -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/include -isystem /temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/i686-w64-mingw32/sys-include -DHAVE_CONFIG_H -I. -I../../../../../mingw-sources/gcc-4.7.2/libgfortran -iquote../../../../../mingw-sources/gcc-4.7.2/libgfortran/io -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../gcc -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../gcc/config -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../libquadmath -I../.././gcc -I../../../../../mingw-sources/gcc-4.7.2/libgfortran/../libgcc -I../libgcc -std=gnu99 -Wall -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition -Wextra -Wwrite-strings -fcx-fortran-rules -ffunction-sections -fdata-sections -g -O2 -pipe -fomit-frame-pointer -I/temp/x32-4.7.2-release-posix-sjlj-rev5/prefix/include -I/temp/x32-4.7.2-release-posix-sjlj-rev5/libs/include -I/temp/mingw-prereq/i686-w64-mingw32-static/include -MT maxloc0_16_i8.lo -MD -MP -MF .deps/maxloc0_16_i8.Tpo -c ../../../../../mingw-sources/gcc-4.7.2/libgfortran/generated/maxloc0_16_i8.c -o maxloc0_16_i8.o >/dev/null 2>&1
make[5]: *** [math_stubs_float.lo] Error 1
make[5]: Leaving directory `/temp/x32-4.7.2-release-posix-sjlj-rev5/build/gcc-4.7.2/i686-w64-mingw32/libstdc++-v3/src/c++98'

Is it bug of mingw-w64 or it my missed configuration line?