error[E0133]: call to unsafe function is unsafe and requires unsafe function or block --> $DIR/foreign-unsafe-fn-called.rs:11:5 | LL | test::free(); | ^^^^^^^^^^^^ call to unsafe function | = note: consult the function's documentation for information on how to avoid undefined behavior error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0133`.