message: dont overuse the wrapper
diff: @@ -51,10 +51,7 @@ impl<'a, 'cfg> BuildContext<'a, 'cfg> {
  units: &'a UnitInterner<'a>,
  extra_compiler_args: HashMap<Unit<'a>, Vec<String>>,
  ) -> CargoResult<BuildContext<'a, 'cfg>> {
  - let mut rustc = config.load_global_rustc(Some(ws))?;
  - if let Some(wrapper) = &build_config.primary_unit_rustc {
  - rustc.set_wrapper(wrapper.clone());
  - }
  + let rustc = config.load_global_rustc(Some(ws))?;
  let host_config = TargetConfig::new(config, &rustc.host)?;
  let target_config = match build_config.requested_target.as_ref() {
  