Rebuilding gcc on Fedora 18 - Howto build i686 packages on a x86_64 machine

[Jon Miller]

Hello,

Hoping this is the correct place to ask this type of question & also hope
it's an easy / quick one. I'll gladly ask elsewhere if not.

We have ran into a compiler issue with gcc and I was looking to apply a small
patch[1] and I've done so via pulling down the gcc src.rpm on my updated
Fedora 18 machine, added the necessary %patch additions to the gcc.spec file
and it has compiled 38 x86_64 packages.

I am also using Spacewalk and in order to ensure these packages were
installed, I bumped up the gcc_release within the gcc.spec file. The problem
is now that when I attempt to update the packages, I get an error about
protected multilib versions[2]. I can not seem to get the rpmbuild process to
produce any i686 versions of the packages. I have tried prefixing my rpmbuild
command with a "setarch i686" but it did not work (sorry, didn't capture my
error).

How do the experts build the i686 & x86_64 packages? (I did notice the "Build
Host" varies between the two, so I'm wondering if I need to build a 32bit
Fedora 18 instance to repeat this build process?)

Thank you,
-- 
Jon Miller