Definition of native toolchain, support for -m32?

[Alex J Lennon <ajlennon@dynamicdevices.co.uk>]

Hi,

I'm having some trouble building chromium which I think is due to a
definition in chromium.inc which uses the host compiler rather than the
Yocto native compile toolchain

CC_host="${BUILD_CC}" export CC_host
CXX_host="${BUILD_CXX}" export CXX_host

This seems to map to the gcc/g++ on my host system which is surely
incorrect?

Am I right in thinking that the correct way to define the Yocto native
toolchain is using something more like this from native.bbclass?

CC_host="${CCACHE}${HOST_PREFIX}gcc ${HOST_CC_ARCH}" export CC_host
CXX_host="${CCACHE}${HOST_PREFIX}g++ ${HOST_CC_ARCH}" export CXX_host

If I do this to eliminate the external dependency I run into a problem
that -m32 is not accepted by the Yocto compiler toolchain (which is
built/running on an x64 Ubuntu 14.04).

Could anybody advise on what steps I might take to have the Yocto native
compile toolchain accepting -m32?

Thanks,

Alex