| error: captured variable cannot escape `FnMut` closure body |
| --> $DIR/issue-40510-1.rs:7:9 |
| | |
| LL | let mut x: Box<()> = Box::new(()); |
| | ----- variable defined here |
| LL | |
| LL | || { |
| | - inferred to be a `FnMut` closure |
| LL | &mut x |
| | ^^^^^- |
| | | | |
| | | variable captured here |
| | returns a reference to a captured variable which escapes the closure body |
| | |
| = note: `FnMut` closures only have access to their captured variables while they are executing... |
| = note: ...therefore, they cannot allow references to captured variables to escape |
| |
| error: aborting due to 1 previous error |
| |
