Trying to build Firefox on OSX with LLVM 2.2

Hello, Simon

ld: warning in ../../../dist/host/lib/libhostmar.a, file is not of
required architecture

I can say nothing about FireFox on darwin, but I frequently build
Seamonkey on linux for testing purposes without any problems. It your
case it looks like 32-bit and 64-bit objects are somehow "mixed"
together (thus warning).

I'd suggest you to track, where these symbols should be defined and
check, that they are linked in properly.