error: cfg attributes not allowed on this item
  --> $DIR/module_cfg_fn.rs:11:5
   |
11 |     #[cfg(not(feature = "foo"))]
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error[E0433]: failed to resolve: use of undeclared type or module `test_module`
  --> $DIR/module_cfg_fn.rs:22:8
   |
22 |     if test_module::test_fn(n) {
   |        ^^^^^^^^^^^ use of undeclared type or module `test_module`