message: Use RealFileName for Session::working_dir as it may also be remapped
diff: @@ -64,7 +64,7 @@ pub(crate) fn new(tcx: TyCtxt<'tcx>, isa: &dyn TargetIsa) -> Self {
  // FIXME: how to get version when building out of tree?
  // Normally this would use option_env!("CFG_VERSION").
  let producer = format!("cg_clif (rustc {})", "unknown version");
  - let comp_dir = tcx.sess.working_dir.0.to_string_lossy().into_owned();
  + let comp_dir = tcx.sess.working_dir.stable_name().to_string_lossy().into_owned();
  let (name, file_info) = match tcx.sess.local_crate_source_file.clone() {
  Some(path) => {
  let name = path.to_string_lossy().into_owned();
  