error[E0133]: call to unsafe function `X::with` is unsafe and requires unsafe function or block --> $DIR/issue-3080.rs:10:5 | LL | X(()).with(); | ^^^^^^^^^^^^ call to unsafe function | = note: consult the function's documentation for information on how to avoid undefined behavior error: aborting due to previous error For more information about this error, try `rustc --explain E0133`.