message: Fix for trunk. Probably it's temporary if they fix -- operator for arg_iterator in trunk.
diff: @@ -4399,7 +4399,11 @@ bool CWriter::visitBuiltinCall(llvm::CallInst &I, llvm::Intrinsic::ID ID,
  if (I.getParent()->getParent()->arg_empty())
  Out << "vararg_dummy_arg";
  else
  +#if ISPC_LLVM_VERSION <= ISPC_LLVM_4_0
  writeOperand(&*(--I.getParent()->getParent()->arg_end()));
  +#else // LLVM 5.0+
  + writeOperand(&*(I.getParent()->getParent()->arg_end()-1));
  +#endif
  Out << ')';
  return true;
  case llvm::Intrinsic::vaend:
  