If you are deploying to 32-bit then build and test on 32-bit.

If you build on 64-bit then test on 32-bit before you deploy.

If you build and test on 64-bit then expect the unexpected problems when you deploy to 32-bit. And expect you will not be able to troubleshoot these problems on a 64-bit OS.

There are just too many differences in the software stack between a 32-bit and 64-bit OS to expect that a build and test on 64-bit will work as expected when deployed to 32-bit. The same applies if you build and test on 32-bit and deploy on 64-bit. At least, that is what we have found where I work.