error[E0658]: `catch` expression is experimental (see issue #31436)
  --> $DIR/feature-gate-catch_expr.rs:12:24
   |
LL |       let catch_result = do catch { //~ ERROR `catch` expression is experimental
   |  ________________________^
LL | |         let x = 5;
LL | |         x
LL | |     };
   | |_____^
   |
   = help: add #![feature(catch_expr)] to the crate attributes to enable

error: aborting due to previous error

For more information about this error, try `rustc --explain E0658`.