error[E0170]: pattern binding `C` is named the same as one of the variants of the type `Foo`
  --> $DIR/issue-88730.rs:11:8
   |
LL | fn foo(C: Foo) {}
   |        ^
   |
   = note: `#[deny(bindings_with_variant_name)]` on by default

error[E0170]: pattern binding `C` is named the same as one of the variants of the type `Foo`
  --> $DIR/issue-88730.rs:14:9
   |
LL |     let C = Foo::D;
   |         ^

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0170`.