error[E0369]: cannot multiply `Bar` by `Bar`
  --> $DIR/borrow-suggestion-109352-2.rs:19:23
   |
LL |     let _ = owned_bar * owned_bar;
   |             --------- ^ --------- Bar
   |             |
   |             Bar
   |
note: an implementation of `Mul` might be missing for `Bar`
  --> $DIR/borrow-suggestion-109352-2.rs:1:1
   |
LL | struct Bar;
   | ^^^^^^^^^^ must implement `Mul`
note: the trait `Mul` must be implemented
  --> $SRC_DIR/core/src/ops/arith.rs:LL:COL

error[E0369]: cannot multiply `&Bar` by `&Bar`
  --> $DIR/borrow-suggestion-109352-2.rs:21:21
   |
LL |     let _ = ref_bar * ref_bar;
   |             ------- ^ ------- &Bar
   |             |
   |             &Bar
   |
   = note: an implementation for `&mut Bar * &mut Bar` exists
help: consider making this expression a mutable borrow
  --> $DIR/borrow-suggestion-109352-2.rs:21:13
   |
LL |     let _ = ref_bar * ref_bar;
   |             ^^^^^^^
help: consider making this expression a mutable borrow
  --> $DIR/borrow-suggestion-109352-2.rs:21:23
   |
LL |     let _ = ref_bar * ref_bar;
   |                       ^^^^^^^

error[E0369]: cannot multiply `&Bar` by `&mut Bar`
  --> $DIR/borrow-suggestion-109352-2.rs:23:21
   |
LL |     let _ = ref_bar * ref_mut_bar;
   |             ------- ^ ----------- &mut Bar
   |             |
   |             &Bar
   |
   = note: an implementation for `&mut Bar * &mut Bar` exists
help: consider making this expression a mutable borrow
  --> $DIR/borrow-suggestion-109352-2.rs:23:13
   |
LL |     let _ = ref_bar * ref_mut_bar;
   |             ^^^^^^^

error[E0308]: mismatched types
  --> $DIR/borrow-suggestion-109352-2.rs:25:27
   |
LL |     let _ = ref_mut_bar * ref_bar;
   |                           ^^^^^^^ types differ in mutability
   |
   = note: expected mutable reference `&mut Bar`
                      found reference `&Bar`

error: aborting due to 4 previous errors

Some errors have detailed explanations: E0308, E0369.
For more information about an error, try `rustc --explain E0308`.