Trait rustc_ap_rustc_data_structures::stable_hasher::HashStable

pub trait HashStable<CTX> {
    fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher);
}

Something that implements HashStable<CTX> can be hashed in a way that is stable across multiple compilation sessions.

Note that HashStable imposes rather more strict requirements than usual hash functions:

• Stable hashes are sometimes used as identifiers. Therefore they must conform to the corresponding PartialEq implementations:

  • x == y implies hash_stable(x) == hash_stable(y), and
  • x != y implies hash_stable(x) != hash_stable(y).

  That second condition is usually not required for hash functions (e.g. Hash). In practice this means that hash_stable must feed any information into the hasher that a PartialEq comparison takes into account. See #49300 for an example where violating this invariant has caused trouble in the past.

• hash_stable() must be independent of the current compilation session. E.g. they must not hash memory addresses or other things that are “randomly” assigned per compilation session.

• hash_stable() must be independent of the host architecture. The StableHasher takes care of endianness and isize/usize platform differences.

Required methods

fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher)

Implementations on Foreign Types

impl<CTX> HashStable<CTX> for i8

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for i16

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for i32

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for i64

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for isize

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for u8

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for u16

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for u32

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for u64

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for usize

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for u128

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for i128

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for char

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for ()

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for NonZeroU32

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for NonZeroUsize

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for f32

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for f64

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for Ordering

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T1: HashStable<CTX>, CTX> HashStable<CTX> for (T1,)

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T1: HashStable<CTX>, T2: HashStable<CTX>, CTX> HashStable<CTX> for (T1, T2)

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T1, T2, T3, CTX> HashStable<CTX> for (T1, T2, T3) where
    T1: HashStable<CTX>,
    T2: HashStable<CTX>,
    T3: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T1, T2, T3, T4, CTX> HashStable<CTX> for (T1, T2, T3, T4) where
    T1: HashStable<CTX>,
    T2: HashStable<CTX>,
    T3: HashStable<CTX>,
    T4: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T: HashStable<CTX>, CTX> HashStable<CTX> for [T]

default fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T: HashStable<CTX>, CTX> HashStable<CTX> for Vec<T>

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<K, V, R, CTX> HashStable<CTX> for IndexMap<K, V, R> where
    K: HashStable<CTX> + Eq + Hash,
    V: HashStable<CTX>,
    R: BuildHasher, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<K, R, CTX> HashStable<CTX> for IndexSet<K, R> where
    K: HashStable<CTX> + Eq + Hash,
    R: BuildHasher, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<A, CTX> HashStable<CTX> for SmallVec<[A; 1]> where
    A: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T: ?Sized + HashStable<CTX>, CTX> HashStable<CTX> for Box<T>

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T: ?Sized + HashStable<CTX>, CTX> HashStable<CTX> for Arc<T>

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for str

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for String

fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for bool

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T, CTX> HashStable<CTX> for Option<T> where
    T: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T1, T2, CTX> HashStable<CTX> for Result<T1, T2> where
    T1: HashStable<CTX>,
    T2: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<'a, T: ?Sized, CTX> HashStable<CTX> for &'a T where
    T: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T, CTX> HashStable<CTX> for Discriminant<T>

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<T, CTX> HashStable<CTX> for RangeInclusive<T> where
    T: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<I: Idx, T, CTX> HashStable<CTX> for IndexVec<I, T> where
    T: HashStable<CTX>, 

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<I: Idx, CTX> HashStable<CTX> for BitSet<I>

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<R: Idx, C: Idx, CTX> HashStable<CTX> for BitMatrix<R, C>

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)

impl<T, CTX> HashStable<CTX> for FiniteBitSet<T> where
    T: HashStable<CTX> + FiniteBitSetTy, 

fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for Path

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX> HashStable<CTX> for PathBuf

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<K, V, R, HCX> HashStable<HCX> for HashMap<K, V, R> where
    K: ToStableHashKey<HCX> + Eq,
    V: HashStable<HCX>,
    R: BuildHasher, 

fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

impl<K, R, HCX> HashStable<HCX> for HashSet<K, R> where
    K: ToStableHashKey<HCX> + Eq,
    R: BuildHasher, 

fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

impl<K, V, HCX> HashStable<HCX> for BTreeMap<K, V> where
    K: ToStableHashKey<HCX>,
    V: HashStable<HCX>, 

fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

impl<K, HCX> HashStable<HCX> for BTreeSet<K> where
    K: ToStableHashKey<HCX>, 

fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

Implementors

impl<CTX> HashStable<CTX> for Fingerprint

fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher)

impl<CTX, T: HashStable<CTX>> HashStable<CTX> for Steal<T>

fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher)

impl<I: Idx, K, V, C> HashStable<C> for SortedIndexMultiMap<I, K, V> where
    K: HashStable<C>,
    V: HashStable<C>, 

fn hash_stable(&self, ctx: &mut C, hasher: &mut StableHasher)

impl<P, T, HCX, const COMPARE_PACKED: bool> HashStable<HCX> for CopyTaggedPtr<P, T, COMPARE_PACKED> where
    P: Pointer + HashStable<HCX>,
    T: Tag + HashStable<HCX>, 

fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

impl<P, T, HCX, const COMPARE_PACKED: bool> HashStable<HCX> for TaggedPtr<P, T, COMPARE_PACKED> where
    P: Pointer + HashStable<HCX>,
    T: Tag + HashStable<HCX>, 

fn hash_stable(&self, hcx: &mut HCX, hasher: &mut StableHasher)

impl<T> HashStable<T> for Svh

fn hash_stable(&self, ctx: &mut T, hasher: &mut StableHasher)

impl<T: HashStable<CTX>, CTX> HashStable<CTX> for ThinVec<T>

fn hash_stable(&self, hcx: &mut CTX, hasher: &mut StableHasher)

impl<T: ?Sized + HashStable<CTX>, CTX> HashStable<CTX> for Rc<T>

fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher)