CC="gcc -B/usr/bin/" ../gcc-4.3.2/configure --prefix=/tools     --with-local-prefix=/tools --disable-nls --disable-shared --disable-libssp     --enable-languages=c --with-gmp=../tools/gmp --with-mpfr=../tools/mpfr

make[2]: Entering directory `/mnt/lfs/gcc-build'
make[3]: Entering directory `/mnt/lfs/gcc-build'
rm -f stage_current
make[3]: Leaving directory `/mnt/lfs/gcc-build'
Comparing stages 2 and 3
warning: ./cc1-checksum.o differs
Bootstrap comparison failure!
./gcc.o differs
make[2]: *** [compare] Error 1
make[2]: Leaving directory `/mnt/lfs/gcc-build'
make[1]: *** [stage3-bubble] Error 2
make[1]: Leaving directory `/mnt/lfs/gcc-build'
make: *** [all] Error 2

sudo make distclean
sudo ./configure

chown -R lfs /mnt/lfs