src/test/ui/feature-gate-linkage.stderr

   1 error[E0658]: the `linkage` attribute is experimental and not portable across platforms (see issue #29603)
   2   --> $DIR/feature-gate-linkage.rs:12:5
   3    |
   4 12 |     #[linkage = "extern_weak"] static foo: isize;
   5    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
   6    |
   7    = help: add #![feature(linkage)] to the crate attributes to enable
   8
   9 error: aborting due to previous error
  10