That's probably due to the toolchain expecting a different version in GCC. Try and symlink /usr/local/lib/gcc/powerpc-wrs-vxworks/4.7.2 to 4.8.0 to get rid of the version conflict for now. Hopefully this fixes your "24 byte" issue. If that doesn't work, I'd double check to make sure that the link script is functioning properly.
Sorry it's been untested, but I literally posted this as soon as I got word that the patches had made it in. I was excited...
Also, past compile time I can't help you unless someone happened to send me a cRIO

There's several other good people on the forums who can help though. And google.
I also deployed code with a hacked gcc 4.7.1 last year and it worked flawlessly, so it *is* possible to get this working...