error: used underscore-prefixed binding
  --> tests/ui/used_underscore_binding.rs:23:5
   |
LL |     _foo + 1
   |     ^^^^
   |
note: binding is defined here
  --> tests/ui/used_underscore_binding.rs:22:22
   |
LL | fn prefix_underscore(_foo: u32) -> u32 {
   |                      ^^^^
   = note: `-D clippy::used-underscore-binding` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::used_underscore_binding)]`

error: used underscore-prefixed binding
  --> tests/ui/used_underscore_binding.rs:29:20
   |
LL |     println!("{}", _foo);
   |                    ^^^^
   |
note: binding is defined here
  --> tests/ui/used_underscore_binding.rs:28:24
   |
LL | fn in_macro_or_desugar(_foo: u32) {
   |                        ^^^^

error: used underscore-prefixed binding
  --> tests/ui/used_underscore_binding.rs:31:16
   |
LL |     assert_eq!(_foo, _foo);
   |                ^^^^
   |
note: binding is defined here
  --> tests/ui/used_underscore_binding.rs:28:24
   |
LL | fn in_macro_or_desugar(_foo: u32) {
   |                        ^^^^

error: used underscore-prefixed binding
  --> tests/ui/used_underscore_binding.rs:31:22
   |
LL |     assert_eq!(_foo, _foo);
   |                      ^^^^
   |
note: binding is defined here
  --> tests/ui/used_underscore_binding.rs:28:24
   |
LL | fn in_macro_or_desugar(_foo: u32) {
   |                        ^^^^

error: used underscore-prefixed binding
  --> tests/ui/used_underscore_binding.rs:46:5
   |
LL |     s._underscore_field += 1;
   |     ^^^^^^^^^^^^^^^^^^^
   |
note: binding is defined here
  --> tests/ui/used_underscore_binding.rs:40:5
   |
LL |     _underscore_field: u32,
   |     ^^^^^^^^^^^^^^^^^^^^^^

error: used underscore-prefixed binding
  --> tests/ui/used_underscore_binding.rs:108:16
   |
LL |         uses_i(_i);
   |                ^^
   |
note: binding is defined here
  --> tests/ui/used_underscore_binding.rs:107:13
   |
LL |         let _i = 5;
   |             ^^

error: aborting due to 6 previous errors