Function null_mut 

pub fn null_mut<T, O>() -> BitPtr<Mut, T, O>
where
    T: BitStore,
    O: BitOrder,

Available on crate feature evm and non-tarpaulin_include only.

Bit-Pointer Sentinel Value

BitPtr does not permit actual null pointers. Instead, it uses the canonical dangling address as a sentinel for uninitialized, useless, locations.

You should use Option<BitPtr> if you need to track nullability.

Original

ptr::null_mut