Macro panic_unwind

macro_rules! panic_unwind {
    () => { ... };
    (if { $($p:tt)* } else { $($n:tt)* }) => { ... };
    ($($p:tt)*) => { ... };
}

Indicates that a panic will be unwound, and can be potentially caught.

This macro passes the provided code because #[cfg(panic = "unwind")] is currently active.