Function zst_ref_out_of_thin_air

crates/vm/src/function/builtin.rs:53–66

(x: T)

}

const fn zst_ref_out_of_thin_air<T: 'static>(x: T) -> &'static T {
    // if T is zero-sized, there's no issue forgetting it - even if it does have a Drop impl, it
    // would never get called anyway if we consider this semantically a Box::leak(Box::new(x))-type
    // operation. if T isn't zero-sized, we don't have to worry about it because we'll fail to compile.
    core::mem::forget(x);
    const {
        if core::mem::size_of::<T>() != 0 {
            panic!("can't use a non-zero-sized type here")
        }
        // SAFETY: we just confirmed that T is zero-sized, so we can
        //         pull a value of it out of thin air.
        unsafe { core::ptr::NonNull::<T>::dangling().as_ref() }
    }
}

/// Get the STATIC_FUNC of the passed function. The same
/// requirements of zero-sized-ness apply, see that documentation for details.