warning: function cannot return without recursing --> $DIR/issue-83150.rs:12:1 | LL | fn func>(iter: &mut T) { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot return without recursing LL | func(&mut iter.map(|x| x + 1)) | ------------------------------ recursive call site | = help: a `loop` may express intention better if this is on purpose = note: `#[warn(unconditional_recursion)]` on by default error[E0275]: overflow evaluating the requirement `Map<&mut std::ops::Range, [closure@$DIR/issue-83150.rs:13:24: 13:27]>: Iterator` | = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_83150`) = note: required for `&mut Map<&mut std::ops::Range, [closure@$DIR/issue-83150.rs:13:24: 13:27]>` to implement `Iterator` = note: 65 redundant requirements hidden = note: required for `&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<..., ...>, ...>, ...>, ...>, ...>, ...>, ...>` to implement `Iterator` = note: the full type name has been written to '$TEST_BUILD_DIR/recursion/issue-83150/issue-83150.long-type-hash.txt' error: aborting due to previous error; 1 warning emitted For more information about this error, try `rustc --explain E0275`.