How to use llvm with ghc7?

Hi, I just got ghc7 and compiled with ghc6.12.1 and default configuration. ghc works fine. So I tried to use llvm. I got: ghc -fllvm badge.hs [1 of 1] Compiling Main ( badge.hs, /tmp/Main.o ) opt: Bitcode stream should be a multiple of 4 bytes in length I am using debian 32bit system, llvm 2.6. -- 竹密岂妨流水过 山高哪阻野云飞