Rust error E0381: used binding `x` isn't initialized

What rustc prints

error[E0381]: used binding `x` isn't initialized
 --> main.rs:3:13
  |
2 |     let x: i32;
  |         - binding declared here but left uninitialized
3 |     let y = x; // error, use of possibly-uninitialized variable
  |             ^ `x` used here but it isn't initialized
  |
help: consider assigning a value
  |
2 |     let x: i32 = 42;
  |                ++++

Real output of rustc 1.99.0 compiling the official example below (2021 edition). Your names and line numbers will differ; the first line is the part to match.

fn main() {
    let x: i32;
    let y = x; // error, use of possibly-uninitialized variable
}

fn main() {
    let x: i32 = 0;
    let y = x; // ok!
}

Related errors

• E0004non-exhaustive patterns
• E0023this pattern has 1 field, but the corresponding tuple variant has 2 fields
• E0164expected tuple struct or tuple variant, found associated function `A::new`
• E0510cannot assign `x` in match guard
• E0527pattern requires 2 elements but array has 4

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