in openCL SDK 1.5 using offline compiler compile CL kernel with -llvm option to generate llvm IR then use llvm-as convert llvm IR -> bitcode will pop error: (llvm version:3.1 svn) llvm-as: hello.ll:39:9: error: expected type define x86_ocl_kernelcc void @hello(i8 addrspace(1)* nocapture %string, i8 addrspace(3)* %pLocalMem, %struct.WorkDim* %pWorkDim, i64* %pWGId, %struct.PaddedDimId* %pBaseGlbId, %struct.PaddedDimId* %pLocalIds, i64* %contextpointer, i64 %iterCount, i8* %pSpecialBuf, i64* %pCurrWI) nounwind { this kernel come from "The openCL programming book" sample code 3-1 http://www.fixstars.com/en/opencl/book/ i've tried some CL kernel, and this error always occurred and their's a bug in offline compiler windows version ,the "save LLVM..." option default file type should be "*.ll" not "*.bc" , the offline compiler generate human readable llvm code.