Setup target-specific variables for the compiler and linkers:

export CC="${LFS_TARGET}-gcc"
export CXX="${LFS_TARGET}-g++"
export AR="${LFS_TARGET}-ar"
export AS="${LFS_TARGET}-as"
export RANLIB="${LFS_TARGET}-ranlib"
export LD="${LFS_TARGET}-ld"
export STRIP="${LFS_TARGET}-strip"

Then add the build variables to ~/.bashrc to prevent issues if you stop and come back later:

echo export CC=\""${CC}\"" >> ~/.bashrc
echo export CXX=\""${CXX}\"" >> ~/.bashrc
echo export AR=\""${AR}\"" >> ~/.bashrc
echo export AS=\""${AS}\"" >> ~/.bashrc
echo export RANLIB=\""${RANLIB}\"" >> ~/.bashrc
echo export LD=\""${LD}\"" >> ~/.bashrc
echo export STRIP=\""${STRIP}\"" >> ~/.bashrc