rust-lang / rust-lang/rust

Borrowcheck error with `break` blames trailing expression for borrowing

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A-diagnostics T-compiler
Dominant language
Rust
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Description

Code
#![allow(unreachable_code)]

pub fn foo() {
    let _x = 'a: {
        if true {
           break 'a &1;
        }
        let temp = 1;
        break 'a &temp;
        panic!()
    };
}
Current output
error[E0597]: `temp` does not live long enough
  --> src/lib.rs:9:18
   |
 8 |         let temp = 1;
   |             ---- binding `temp` declared here
 9 |         break 'a &temp;
   |                  ^^^^^ borrowed value does not live long enough
10 |         panic!()
   |         -------- borrow later used here
11 |     };
   |     - `temp` dropped here while still borrowed

For more information about this error, try `rustc --explain E0597`.
error: could not compile `playground` (lib) due to 1 previous error
Desired output
Don't point to the panic.
Rationale and extra context

No response

Other cases

Rust Version
Reproducible on the playground with version 1.91.0-nightly (2025-08-16 2e2642e641a941f0a140)
Anything else?

No response

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First steps

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Research direction

Reproduce the borrow-checker diagnostic from the provided Rust snippet on the playground with Rust 1.91.0-nightly (2025-08-16). Compare the current and desired diagnostics, with completion indicated when the trailing panic!() is no longer identified as the later borrow use.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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