std::mem::POST_DROP_U64

pub const POST_DROP_U64: u64 = ((((POST_DROP_U8 as u32) << 24 | (POST_DROP_U8 as u32) << 16 |
       (POST_DROP_U8 as u32) << 8 | (POST_DROP_U8 as u32)) as u64) << 32 |
     (((POST_DROP_U8 as u32) << 24 | (POST_DROP_U8 as u32) << 16 |
           (POST_DROP_U8 as u32) << 8 | (POST_DROP_U8 as u32)) as u64))

Unstable