But, when comparing [1] to [2], the rules file has a nice test that says "if DEB_HOST_ARCH is armhf, set the LLVM_HOST_TRIPLE to armv6k..." which seems to confirm a build configuration change.
[1] http://raspbian.raspberrypi.org/raspbian/pool/main/l/llvm-to...
[2] http://raspbian.raspberrypi.org/raspbian/pool/main/l/llvm-to...