error[E0381]: used binding `x` isn't initialized --> $DIR/borrowck-block-unint.rs:4:11 | LL | let x: isize; | - binding declared here but left uninitialized LL | force(|| { | ^^ `x` used here but it isn't initialized LL | println!("{}", x); | - borrow occurs due to use in closure | help: consider assigning a value | LL | let x: isize = 0; | +++ error: aborting due to previous error For more information about this error, try `rustc --explain E0381`.