/// even in unsafe code. As a consequence, 0-initializing a variable of reference
/// type causes instantaneous undefined behavior, no matter whether that reference
/// ever gets used to access memory:
-/// ```rust,ignore
+/// ```rust,no_run
/// use std::mem;
///
/// let x: &i32 = mem::zeroed(); // undefined behavior!
/// // Set it to a valid value.
/// x.set(&0);
/// // Extract the initialized data -- this is only allowed *after* properly
-/// initializing `x`!
+/// // initializing `x`!
/// let x = unsafe { x.into_initialized() };
/// ```
/// The compiler then knows to not optimize this code.