error: reached the recursion limit while instantiating `rec::<&mut &mut &mut &mut &mut &... &mut &mut &mut &mut &mut Empty>` --> $DIR/issue-67552.rs:28:9 | LL | rec(identity(&mut it)) | ^^^^^^^^^^^^^^^^^^^^^^ | note: `rec` defined here --> $DIR/issue-67552.rs:21:1 | LL | / fn rec(mut it: T) LL | | where LL | | T: Iterator, | |________________^ = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-67552.polonius/issue-67552.long-type.txt' error: aborting due to 1 previous error