error[E0381]: used binding `w` isn't initialized --> $DIR/borrowck-use-in-index-lvalue.rs:3:5 | LL | let w: &mut [isize]; | - binding declared here but left uninitialized LL | w[5] = 0; | ^^^^ `*w` used here but it isn't initialized | help: consider assigning a value | LL | let w: &mut [isize] = todo!(); | +++++++++ error[E0381]: used binding `w` isn't initialized --> $DIR/borrowck-use-in-index-lvalue.rs:6:5 | LL | let mut w: &mut [isize]; | ----- binding declared here but left uninitialized LL | w[5] = 0; | ^^^^ `*w` used here but it isn't initialized | help: consider assigning a value | LL | let mut w: &mut [isize] = todo!(); | +++++++++ error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0381`.