error[E0599]: no variant or associated item named `Baz` found for enum `Foo` in the current scope
  --> $DIR/issue-28971.rs:7:18
   |
LL | enum Foo {
   | -------- variant or associated item `Baz` not found for this enum
...
LL |             Foo::Baz(..) => (),
   |                  ^^^ variant or associated item not found in `Foo`
   |
help: there is a variant with a similar name
   |
LL |             Foo::Bar(..) => (),
   |                  ~~~

error[E0596]: cannot borrow `f` as mutable, as it is not declared as mutable
  --> $DIR/issue-28971.rs:15:5
   |
LL |     f();
   |     ^ cannot borrow as mutable
   |
help: consider changing this to be mutable
   |
LL | fn foo<F>(mut f: F) where F: FnMut() {
   |           +++

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0596, E0599.
For more information about an error, try `rustc --explain E0596`.