error[E0307]: invalid `self` type: &SomeType
  --> $DIR/issue-27522.rs:16:22
   |
16 |     fn handler(self: &SomeType);
   |                      ^^^^^^^^^
   |
   = note: type must be `Self` or a type that dereferences to it`
   = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`

error: arbitrary `self` types are unstable (see issue #44874)
  --> $DIR/issue-27522.rs:16:22
   |
16 |     fn handler(self: &SomeType);
   |                      ^^^^^^^^^
   |
   = help: add #![feature(arbitrary_self_types)] to the crate attributes to enable
   = help: consider changing to `self`, `&self`, `&mut self`, or `self: Box<Self>`

error: aborting due to 2 previous errors