Patch `std` to be compatible with Rust nightly-2017-12-01

This only fixes things enough so that the project compiles again. More standard library changes from upstream Rust will be pulled in later.

11 files changed, 262 insertions, 508 deletions

diff --git a/ctr-std/src/collections/hash/map.rs b/ctr-std/src/collections/hash/map.rs
index 746e180..7a79a47 100644
--- a/ctr-std/src/collections/hash/map.rs
+++ b/ctr-std/src/collections/hash/map.rs
@@ -20,8 +20,8 @@ use hash::{Hash, Hasher, BuildHasher, SipHasher13};
 use iter::{FromIterator, FusedIterator};
 use mem::{self, replace};
 use ops::{Deref, Index, InPlace, Place, Placer};
-use rand::{self, Rng};
 use ptr;
+use sys;
 
 use super::table::{self, Bucket, EmptyBucket, FullBucket, FullBucketMut, RawTable, SafeHash};
 use super::table::BucketState::{Empty, Full};
@@ -203,7 +203,7 @@ const DISPLACEMENT_THRESHOLD: usize = 128;
 // so we round that up to 128.
 //
 // At a load factor of α, the odds of finding the target bucket after exactly n
-// unsuccesful probes[1] are
+// unsuccessful probes[1] are
 //
 // Pr_α{displacement = n} =
 // (1 - α) / α * ∑_{k≥1} e^(-kα) * (kα)^(k+n) / (k + n)! * (1 - kα / (k + n + 1))
@@ -419,7 +419,7 @@ fn search_hashed<K, V, M, F>(table: M, hash: SafeHash, mut is_match: F) -> Inter
             Empty(bucket) => {
                 // Found a hole!
                 return InternalEntry::Vacant {
-                    hash: hash,
+                    hash,
                     elem: NoElem(bucket, displacement),
                 };
             }
@@ -433,7 +433,7 @@ fn search_hashed<K, V, M, F>(table: M, hash: SafeHash, mut is_match: F) -> Inter
             // We can finish the search early if we hit any bucket
             // with a lower distance to initial bucket than we've probed.
             return InternalEntry::Vacant {
-                hash: hash,
+                hash,
                 elem: NeqElem(full, probe_displacement),
             };
         }
@@ -588,6 +588,9 @@ impl<K, V, S> HashMap<K, V, S>
 impl<K: Hash + Eq, V> HashMap<K, V, RandomState> {
     /// Creates an empty `HashMap`.
     ///
+    /// The hash map is initially created with a capacity of 0, so it will not allocate until it
+    /// is first inserted into.
+    ///
     /// # Examples
     ///
     /// ```
@@ -646,7 +649,7 @@ impl<K, V, S> HashMap<K, V, S>
     #[stable(feature = "hashmap_build_hasher", since = "1.7.0")]
     pub fn with_hasher(hash_builder: S) -> HashMap<K, V, S> {
         HashMap {
-            hash_builder: hash_builder,
+            hash_builder,
             resize_policy: DefaultResizePolicy::new(),
             table: RawTable::new(0),
         }
@@ -679,8 +682,8 @@ impl<K, V, S> HashMap<K, V, S>
         let resize_policy = DefaultResizePolicy::new();
         let raw_cap = resize_policy.raw_capacity(capacity);
         HashMap {
-            hash_builder: hash_builder,
-            resize_policy: resize_policy,
+            hash_builder,
+            resize_policy,
             table: RawTable::new(raw_cap),
         }
     }
@@ -688,6 +691,17 @@ impl<K, V, S> HashMap<K, V, S>
     /// Returns a reference to the map's [`BuildHasher`].
     ///
     /// [`BuildHasher`]: ../../std/hash/trait.BuildHasher.html
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::HashMap;
+    /// use std::collections::hash_map::RandomState;
+    ///
+    /// let hasher = RandomState::new();
+    /// let map: HashMap<isize, isize> = HashMap::with_hasher(hasher);
+    /// let hasher: &RandomState = map.hasher();
+    /// ```
     #[stable(feature = "hashmap_public_hasher", since = "1.9.0")]
     pub fn hasher(&self) -> &S {
         &self.hash_builder
@@ -1099,6 +1113,7 @@ impl<K, V, S> HashMap<K, V, S>
     /// assert_eq!(map.get(&2), None);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[inline]
     pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&V>
         where K: Borrow<Q>,
               Q: Hash + Eq
@@ -1347,7 +1362,7 @@ pub struct Iter<'a, K: 'a, V: 'a> {
     inner: table::Iter<'a, K, V>,
 }
 
-// FIXME(#19839) Remove in favor of `#[derive(Clone)]`
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'a, K, V> Clone for Iter<'a, K, V> {
     fn clone(&self) -> Iter<'a, K, V> {
@@ -1400,7 +1415,7 @@ pub struct Keys<'a, K: 'a, V: 'a> {
     inner: Iter<'a, K, V>,
 }
 
-// FIXME(#19839) Remove in favor of `#[derive(Clone)]`
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'a, K, V> Clone for Keys<'a, K, V> {
     fn clone(&self) -> Keys<'a, K, V> {
@@ -1429,7 +1444,7 @@ pub struct Values<'a, K: 'a, V: 'a> {
     inner: Iter<'a, K, V>,
 }
 
-// FIXME(#19839) Remove in favor of `#[derive(Clone)]`
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'a, K, V> Clone for Values<'a, K, V> {
     fn clone(&self) -> Values<'a, K, V> {
@@ -1496,14 +1511,14 @@ impl<'a, K, V> InternalEntry<K, V, &'a mut RawTable<K, V>> {
             InternalEntry::Occupied { elem } => {
                 Some(Occupied(OccupiedEntry {
                     key: Some(key),
-                    elem: elem,
+                    elem,
                 }))
             }
             InternalEntry::Vacant { hash, elem } => {
                 Some(Vacant(VacantEntry {
-                    hash: hash,
-                    key: key,
-                    elem: elem,
+                    hash,
+                    key,
+                    elem,
                 }))
             }
             InternalEntry::TableIsEmpty => None,
@@ -1618,7 +1633,7 @@ impl<'a, K, V, S> IntoIterator for &'a mut HashMap<K, V, S>
     type Item = (&'a K, &'a mut V);
     type IntoIter = IterMut<'a, K, V>;
 
-    fn into_iter(mut self) -> IterMut<'a, K, V> {
+    fn into_iter(self) -> IterMut<'a, K, V> {
         self.iter_mut()
     }
 }
@@ -1999,6 +2014,68 @@ impl<'a, K, V> Entry<'a, K, V> {
             Vacant(ref entry) => entry.key(),
         }
     }
+
+    /// Provides in-place mutable access to an occupied entry before any
+    /// potential inserts into the map.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(entry_and_modify)]
+    /// use std::collections::HashMap;
+    ///
+    /// let mut map: HashMap<&str, u32> = HashMap::new();
+    ///
+    /// map.entry("poneyland")
+    ///    .and_modify(|e| { *e += 1 })
+    ///    .or_insert(42);
+    /// assert_eq!(map["poneyland"], 42);
+    ///
+    /// map.entry("poneyland")
+    ///    .and_modify(|e| { *e += 1 })
+    ///    .or_insert(42);
+    /// assert_eq!(map["poneyland"], 43);
+    /// ```
+    #[unstable(feature = "entry_and_modify", issue = "44733")]
+    pub fn and_modify<F>(self, mut f: F) -> Self
+        where F: FnMut(&mut V)
+    {
+        match self {
+            Occupied(mut entry) => {
+                f(entry.get_mut());
+                Occupied(entry)
+            },
+            Vacant(entry) => Vacant(entry),
+        }
+    }
+
+}
+
+impl<'a, K, V: Default> Entry<'a, K, V> {
+    #[unstable(feature = "entry_or_default", issue = "44324")]
+    /// Ensures a value is in the entry by inserting the default value if empty,
+    /// and returns a mutable reference to the value in the entry.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(entry_or_default)]
+    /// # fn main() {
+    /// use std::collections::HashMap;
+    ///
+    /// let mut map: HashMap<&str, Option<u32>> = HashMap::new();
+    /// map.entry("poneyland").or_default();
+    ///
+    /// assert_eq!(map["poneyland"], None);
+    /// # }
+    /// ```
+    pub fn or_default(self) -> &'a mut V {
+        match self {
+            Occupied(entry) => entry.into_mut(),
+            Vacant(entry) => entry.insert(Default::default()),
+        }
+    }
+
 }
 
 impl<'a, K, V> OccupiedEntry<'a, K, V> {
@@ -2161,6 +2238,68 @@ impl<'a, K, V> OccupiedEntry<'a, K, V> {
     fn take_key(&mut self) -> Option<K> {
         self.key.take()
     }
+
+    /// Replaces the entry, returning the old key and value. The new key in the hash map will be
+    /// the key used to create this entry.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(map_entry_replace)]
+    /// use std::collections::hash_map::{Entry, HashMap};
+    /// use std::rc::Rc;
+    ///
+    /// let mut map: HashMap<Rc<String>, u32> = HashMap::new();
+    /// map.insert(Rc::new("Stringthing".to_string()), 15);
+    ///
+    /// let my_key = Rc::new("Stringthing".to_string());
+    ///
+    /// if let Entry::Occupied(entry) = map.entry(my_key) {
+    ///     // Also replace the key with a handle to our other key.
+    ///     let (old_key, old_value): (Rc<String>, u32) = entry.replace_entry(16);
+    /// }
+    ///
+    /// ```
+    #[unstable(feature = "map_entry_replace", issue = "44286")]
+    pub fn replace_entry(mut self, value: V) -> (K, V) {
+        let (old_key, old_value) = self.elem.read_mut();
+
+        let old_key = mem::replace(old_key, self.key.unwrap());
+        let old_value = mem::replace(old_value, value);
+
+        (old_key, old_value)
+    }
+
+    /// Replaces the key in the hash map with the key used to create this entry.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(map_entry_replace)]
+    /// use std::collections::hash_map::{Entry, HashMap};
+    /// use std::rc::Rc;
+    ///
+    /// let mut map: HashMap<Rc<String>, u32> = HashMap::new();
+    /// let mut known_strings: Vec<Rc<String>> = Vec::new();
+    ///
+    /// // Initialise known strings, run program, etc.
+    ///
+    /// reclaim_memory(&mut map, &known_strings);
+    ///
+    /// fn reclaim_memory(map: &mut HashMap<Rc<String>, u32>, known_strings: &[Rc<String>] ) {
+    ///     for s in known_strings {
+    ///         if let Entry::Occupied(entry) = map.entry(s.clone()) {
+    ///             // Replaces the entry's key with our version of it in `known_strings`.
+    ///             entry.replace_key();
+    ///         }
+    ///     }
+    /// }
+    /// ```
+    #[unstable(feature = "map_entry_replace", issue = "44286")]
+    pub fn replace_key(mut self) -> K {
+        let (old_key, _) = self.elem.read_mut();
+        mem::replace(old_key, self.key.unwrap())
+    }
 }
 
 impl<'a, K: 'a, V: 'a> VacantEntry<'a, K, V> {
@@ -2354,9 +2493,7 @@ impl RandomState {
         // increment one of the seeds on every RandomState creation, giving
         // every corresponding HashMap a different iteration order.
         thread_local!(static KEYS: Cell<(u64, u64)> = {
-            let r = rand::OsRng::new();
-            let mut r = r.expect("failed to create an OS RNG");
-            Cell::new((r.gen(), r.gen()))
+            Cell::new(sys::hashmap_random_keys())
         });
 
         KEYS.with(|keys| {
@@ -2448,6 +2585,7 @@ impl<K, S, Q: ?Sized> super::Recover<Q> for HashMap<K, (), S>
 {
     type Key = K;
 
+    #[inline]
     fn get(&self, key: &Q) -> Option<&K> {
         self.search(key).into_occupied_bucket().map(|bucket| bucket.into_refs().0)
     }
@@ -2460,6 +2598,7 @@ impl<K, S, Q: ?Sized> super::Recover<Q> for HashMap<K, (), S>
         self.search_mut(key).into_occupied_bucket().map(|bucket| pop_internal(bucket).0)
     }
 
+    #[inline]
     fn replace(&mut self, key: K) -> Option<K> {
         self.reserve(1);
 
diff --git a/ctr-std/src/collections/hash/set.rs b/ctr-std/src/collections/hash/set.rs
index d80df5f..51698ce 100644
--- a/ctr-std/src/collections/hash/set.rs
+++ b/ctr-std/src/collections/hash/set.rs
@@ -123,13 +123,16 @@ pub struct HashSet<T, S = RandomState> {
 }
 
 impl<T: Hash + Eq> HashSet<T, RandomState> {
-    /// Creates an empty HashSet.
+    /// Creates an empty `HashSet`.
+    ///
+    /// The hash set is initially created with a capacity of 0, so it will not allocate until it
+    /// is first inserted into.
     ///
     /// # Examples
     ///
     /// ```
     /// use std::collections::HashSet;
-    /// let mut set: HashSet<i32> = HashSet::new();
+    /// let set: HashSet<i32> = HashSet::new();
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -146,7 +149,8 @@ impl<T: Hash + Eq> HashSet<T, RandomState> {
     ///
     /// ```
     /// use std::collections::HashSet;
-    /// let mut set: HashSet<i32> = HashSet::with_capacity(10);
+    /// let set: HashSet<i32> = HashSet::with_capacity(10);
+    /// assert!(set.capacity() >= 10);
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -215,6 +219,17 @@ impl<T, S> HashSet<T, S>
     /// Returns a reference to the set's [`BuildHasher`].
     ///
     /// [`BuildHasher`]: ../../std/hash/trait.BuildHasher.html
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::HashSet;
+    /// use std::collections::hash_map::RandomState;
+    ///
+    /// let hasher = RandomState::new();
+    /// let set: HashSet<i32> = HashSet::with_hasher(hasher);
+    /// let hasher: &RandomState = set.hasher();
+    /// ```
     #[stable(feature = "hashmap_public_hasher", since = "1.9.0")]
     pub fn hasher(&self) -> &S {
         self.map.hasher()
@@ -249,6 +264,7 @@ impl<T, S> HashSet<T, S>
     /// use std::collections::HashSet;
     /// let mut set: HashSet<i32> = HashSet::new();
     /// set.reserve(10);
+    /// assert!(set.capacity() >= 10);
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn reserve(&mut self, additional: usize) {
@@ -312,19 +328,19 @@ impl<T, S> HashSet<T, S>
     ///     println!("{}", x); // Print 1
     /// }
     ///
-    /// let diff: HashSet<_> = a.difference(&b).cloned().collect();
-    /// assert_eq!(diff, [1].iter().cloned().collect());
+    /// let diff: HashSet<_> = a.difference(&b).collect();
+    /// assert_eq!(diff, [1].iter().collect());
     ///
     /// // Note that difference is not symmetric,
     /// // and `b - a` means something else:
-    /// let diff: HashSet<_> = b.difference(&a).cloned().collect();
-    /// assert_eq!(diff, [4].iter().cloned().collect());
+    /// let diff: HashSet<_> = b.difference(&a).collect();
+    /// assert_eq!(diff, [4].iter().collect());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn difference<'a>(&'a self, other: &'a HashSet<T, S>) -> Difference<'a, T, S> {
         Difference {
             iter: self.iter(),
-            other: other,
+            other,
         }
     }
 
@@ -343,11 +359,11 @@ impl<T, S> HashSet<T, S>
     ///     println!("{}", x);
     /// }
     ///
-    /// let diff1: HashSet<_> = a.symmetric_difference(&b).cloned().collect();
-    /// let diff2: HashSet<_> = b.symmetric_difference(&a).cloned().collect();
+    /// let diff1: HashSet<_> = a.symmetric_difference(&b).collect();
+    /// let diff2: HashSet<_> = b.symmetric_difference(&a).collect();
     ///
     /// assert_eq!(diff1, diff2);
-    /// assert_eq!(diff1, [1, 4].iter().cloned().collect());
+    /// assert_eq!(diff1, [1, 4].iter().collect());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn symmetric_difference<'a>(&'a self,
@@ -371,14 +387,14 @@ impl<T, S> HashSet<T, S>
     ///     println!("{}", x);
     /// }
     ///
-    /// let intersection: HashSet<_> = a.intersection(&b).cloned().collect();
-    /// assert_eq!(intersection, [2, 3].iter().cloned().collect());
+    /// let intersection: HashSet<_> = a.intersection(&b).collect();
+    /// assert_eq!(intersection, [2, 3].iter().collect());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn intersection<'a>(&'a self, other: &'a HashSet<T, S>) -> Intersection<'a, T, S> {
         Intersection {
             iter: self.iter(),
-            other: other,
+            other,
         }
     }
 
@@ -397,8 +413,8 @@ impl<T, S> HashSet<T, S>
     ///     println!("{}", x);
     /// }
     ///
-    /// let union: HashSet<_> = a.union(&b).cloned().collect();
-    /// assert_eq!(union, [1, 2, 3, 4].iter().cloned().collect());
+    /// let union: HashSet<_> = a.union(&b).collect();
+    /// assert_eq!(union, [1, 2, 3, 4].iter().collect());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn union<'a>(&'a self, other: &'a HashSet<T, S>) -> Union<'a, T, S> {
@@ -440,6 +456,22 @@ impl<T, S> HashSet<T, S>
     }
 
     /// Clears the set, returning all elements in an iterator.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::HashSet;
+    ///
+    /// let mut set: HashSet<_> = [1, 2, 3].iter().cloned().collect();
+    /// assert!(!set.is_empty());
+    ///
+    /// // print 1, 2, 3 in an arbitrary order
+    /// for i in set.drain() {
+    ///     println!("{}", i);
+    /// }
+    ///
+    /// assert!(set.is_empty());
+    /// ```
     #[inline]
     #[stable(feature = "drain", since = "1.6.0")]
     pub fn drain(&mut self) -> Drain<T> {
diff --git a/ctr-std/src/collections/hash/table.rs b/ctr-std/src/collections/hash/table.rs
index 3844690..7e623a0 100644
--- a/ctr-std/src/collections/hash/table.rs
+++ b/ctr-std/src/collections/hash/table.rs
@@ -353,14 +353,14 @@ impl<K, V, M: Deref<Target = RawTable<K, V>>> Bucket<K, V, M> {
         let ib_index = ib_index & table.capacity_mask;
         Bucket {
             raw: table.raw_bucket_at(ib_index),
-            table: table,
+            table,
         }
     }
 
     pub fn first(table: M) -> Bucket<K, V, M> {
         Bucket {
             raw: table.raw_bucket_at(0),
-            table: table,
+            table,
         }
     }
 
@@ -455,7 +455,7 @@ impl<K, V, M: Deref<Target = RawTable<K, V>>> EmptyBucket<K, V, M> {
         match self.next().peek() {
             Full(bucket) => {
                 Ok(GapThenFull {
-                    gap: gap,
+                    gap,
                     full: bucket,
                 })
             }
@@ -563,7 +563,7 @@ impl<'t, K, V> FullBucket<K, V, &'t mut RawTable<K, V>> {
     ///
     /// This works similarly to `put`, building an `EmptyBucket` out of the
     /// taken bucket.
-    pub fn take(mut self) -> (EmptyBucket<K, V, &'t mut RawTable<K, V>>, K, V) {
+    pub fn take(self) -> (EmptyBucket<K, V, &'t mut RawTable<K, V>>, K, V) {
         self.table.size -= 1;
 
         unsafe {
@@ -717,26 +717,25 @@ fn calculate_offsets(hashes_size: usize,
     (pairs_offset, end_of_pairs, oflo)
 }
 
-// Returns a tuple of (minimum required malloc alignment, hash_offset,
+// Returns a tuple of (minimum required malloc alignment,
 // array_size), from the start of a mallocated array.
 fn calculate_allocation(hash_size: usize,
                         hash_align: usize,
                         pairs_size: usize,
                         pairs_align: usize)
-                        -> (usize, usize, usize, bool) {
-    let hash_offset = 0;
+                        -> (usize, usize, bool) {
     let (_, end_of_pairs, oflo) = calculate_offsets(hash_size, pairs_size, pairs_align);
 
     let align = cmp::max(hash_align, pairs_align);
 
-    (align, hash_offset, end_of_pairs, oflo)
+    (align, end_of_pairs, oflo)
 }
 
 #[test]
 fn test_offset_calculation() {
-    assert_eq!(calculate_allocation(128, 8, 16, 8), (8, 0, 144, false));
-    assert_eq!(calculate_allocation(3, 1, 2, 1), (1, 0, 5, false));
-    assert_eq!(calculate_allocation(6, 2, 12, 4), (4, 0, 20, false));
+    assert_eq!(calculate_allocation(128, 8, 16, 8), (8, 144, false));
+    assert_eq!(calculate_allocation(3, 1, 2, 1), (1, 5, false));
+    assert_eq!(calculate_allocation(6, 2, 12, 4), (4, 20, false));
     assert_eq!(calculate_offsets(128, 15, 4), (128, 143, false));
     assert_eq!(calculate_offsets(3, 2, 4), (4, 6, false));
     assert_eq!(calculate_offsets(6, 12, 4), (8, 20, false));
@@ -768,10 +767,10 @@ impl<K, V> RawTable<K, V> {
         // This is great in theory, but in practice getting the alignment
         // right is a little subtle. Therefore, calculating offsets has been
         // factored out into a different function.
-        let (alignment, hash_offset, size, oflo) = calculate_allocation(hashes_size,
-                                                                        align_of::<HashUint>(),
-                                                                        pairs_size,
-                                                                        align_of::<(K, V)>());
+        let (alignment, size, oflo) = calculate_allocation(hashes_size,
+                                                           align_of::<HashUint>(),
+                                                           pairs_size,
+                                                           align_of::<(K, V)>());
         assert!(!oflo, "capacity overflow");
 
         // One check for overflow that covers calculation and rounding of size.
@@ -784,7 +783,7 @@ impl<K, V> RawTable<K, V> {
         let buffer = Heap.alloc(Layout::from_size_align(size, alignment).unwrap())
             .unwrap_or_else(|e| Heap.oom(e));
 
-        let hashes = buffer.offset(hash_offset as isize) as *mut HashUint;
+        let hashes = buffer as *mut HashUint;
 
         RawTable {
             capacity_mask: capacity.wrapping_sub(1),
@@ -860,8 +859,8 @@ impl<K, V> RawTable<K, V> {
         // Replace the marker regardless of lifetime bounds on parameters.
         IntoIter {
             iter: RawBuckets {
-                raw: raw,
-                elems_left: elems_left,
+                raw,
+                elems_left,
                 marker: marker::PhantomData,
             },
             table: self,
@@ -873,8 +872,8 @@ impl<K, V> RawTable<K, V> {
         // Replace the marker regardless of lifetime bounds on parameters.
         Drain {
             iter: RawBuckets {
-                raw: raw,
-                elems_left: elems_left,
+                raw,
+                elems_left,
                 marker: marker::PhantomData,
             },
             table: Shared::from(self),
@@ -925,7 +924,7 @@ struct RawBuckets<'a, K, V> {
     marker: marker::PhantomData<&'a ()>,
 }
 
-// FIXME(#19839) Remove in favor of `#[derive(Clone)]`
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 impl<'a, K, V> Clone for RawBuckets<'a, K, V> {
     fn clone(&self) -> RawBuckets<'a, K, V> {
         RawBuckets {
@@ -976,7 +975,7 @@ pub struct Iter<'a, K: 'a, V: 'a> {
 unsafe impl<'a, K: Sync, V: Sync> Sync for Iter<'a, K, V> {}
 unsafe impl<'a, K: Sync, V: Sync> Send for Iter<'a, K, V> {}
 
-// FIXME(#19839) Remove in favor of `#[derive(Clone)]`
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
 impl<'a, K, V> Clone for Iter<'a, K, V> {
     fn clone(&self) -> Iter<'a, K, V> {
         Iter {
@@ -1157,6 +1156,7 @@ impl<K: Clone, V: Clone> Clone for RawTable<K, V> {
             }
 
             new_ht.size = self.size();
+            new_ht.set_tag(self.tag());
 
             new_ht
         }
@@ -1183,10 +1183,10 @@ unsafe impl<#[may_dangle] K, #[may_dangle] V> Drop for RawTable<K, V> {
 
         let hashes_size = self.capacity() * size_of::<HashUint>();
         let pairs_size = self.capacity() * size_of::<(K, V)>();
-        let (align, _, size, oflo) = calculate_allocation(hashes_size,
-                                                          align_of::<HashUint>(),
-                                                          pairs_size,
-                                                          align_of::<(K, V)>());
+        let (align, size, oflo) = calculate_allocation(hashes_size,
+                                                       align_of::<HashUint>(),
+                                                       pairs_size,
+                                                       align_of::<(K, V)>());
 
         debug_assert!(!oflo, "should be impossible");
 
diff --git a/ctr-std/src/lib.rs b/ctr-std/src/lib.rs
index 28ab259..4c08fe2 100644
--- a/ctr-std/src/lib.rs
+++ b/ctr-std/src/lib.rs
@@ -64,8 +64,6 @@ use prelude::v1::*;
                  debug_assert_ne, unreachable, unimplemented, write, writeln, try)]
 extern crate core as __core;
 
-#[allow(deprecated)] extern crate rand as core_rand;
-
 #[macro_use]
 #[macro_reexport(vec, format)]
 extern crate alloc;
@@ -184,20 +182,8 @@ mod sys;
 
 // Private support modules
 mod panicking;
-mod rand;
 mod memchr;
 
 // The runtime entry point and a few unstable public functions used by the
 // compiler
 pub mod rt;
-
-// Some external utilities of the standard library rely on randomness (aka
-// rustc_back::TempDir and tests) and need a way to get at the OS rng we've got
-// here. This module is not at all intended for stabilization as-is, however,
-// but it may be stabilized long-term. As a result we're exposing a hidden,
-// unstable module so we can get our build working.
-#[doc(hidden)]
-#[unstable(feature = "rand", issue = "0")]
-pub mod __rand {
-    pub use rand::{thread_rng, ThreadRng, Rng};
-}
diff --git a/ctr-std/src/panic.rs b/ctr-std/src/panic.rs
index 58356bc..e73e0a6 100644
--- a/ctr-std/src/panic.rs
+++ b/ctr-std/src/panic.rs
@@ -11,6 +11,7 @@
 //! Panic support in the standard library
 
 #![stable(feature = "std_panic", since = "1.9.0")]
+#![allow(auto_impl)]
 
 use any::Any;
 use cell::UnsafeCell;
diff --git a/ctr-std/src/path.rs b/ctr-std/src/path.rs
index d13baea..2435efd 100644
--- a/ctr-std/src/path.rs
+++ b/ctr-std/src/path.rs
@@ -106,7 +106,6 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
-use ascii::*;
 use borrow::{Borrow, Cow};
 use cmp;
 use error::Error;
diff --git a/ctr-std/src/rand/mod.rs b/ctr-std/src/rand/mod.rs
deleted file mode 100644
index b853e83..0000000
--- a/ctr-std/src/rand/mod.rs
+++ /dev/null
@@ -1,286 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-//! Utilities for random number generation
-//!
-//! The key functions are `random()` and `Rng::gen()`. These are polymorphic
-//! and so can be used to generate any type that implements `Rand`. Type inference
-//! means that often a simple call to `rand::random()` or `rng.gen()` will
-//! suffice, but sometimes an annotation is required, e.g. `rand::random::<f64>()`.
-//!
-//! See the `distributions` submodule for sampling random numbers from
-//! distributions like normal and exponential.
-//!
-//! # Thread-local RNG
-//!
-//! There is built-in support for a RNG associated with each thread stored
-//! in thread-local storage. This RNG can be accessed via `thread_rng`, or
-//! used implicitly via `random`. This RNG is normally randomly seeded
-//! from an operating-system source of randomness, e.g. `/dev/urandom` on
-//! Unix systems, and will automatically reseed itself from this source
-//! after generating 32 KiB of random data.
-//!
-//! # Cryptographic security
-//!
-//! An application that requires an entropy source for cryptographic purposes
-//! must use `OsRng`, which reads randomness from the source that the operating
-//! system provides (e.g. `/dev/urandom` on Unixes or `CryptGenRandom()` on Windows).
-//! The other random number generators provided by this module are not suitable
-//! for such purposes.
-//!
-//! *Note*: many Unix systems provide `/dev/random` as well as `/dev/urandom`.
-//! This module uses `/dev/urandom` for the following reasons:
-//!
-//! -   On Linux, `/dev/random` may block if entropy pool is empty; `/dev/urandom` will not block.
-//!     This does not mean that `/dev/random` provides better output than
-//!     `/dev/urandom`; the kernel internally runs a cryptographically secure pseudorandom
-//!     number generator (CSPRNG) based on entropy pool for random number generation,
-//!     so the "quality" of `/dev/random` is not better than `/dev/urandom` in most cases.
-//!     However, this means that `/dev/urandom` can yield somewhat predictable randomness
-//!     if the entropy pool is very small, such as immediately after first booting.
-//!     Linux 3.17 added the `getrandom(2)` system call which solves the issue: it blocks if entropy
-//!     pool is not initialized yet, but it does not block once initialized.
-//!     `getrandom(2)` was based on `getentropy(2)`, an existing system call in OpenBSD.
-//!     `OsRng` tries to use `getrandom(2)` if available, and use `/dev/urandom` fallback if not.
-//!     If an application does not have `getrandom` and likely to be run soon after first booting,
-//!     or on a system with very few entropy sources, one should consider using `/dev/random` via
-//!     `ReaderRng`.
-//! -   On some systems (e.g. FreeBSD, OpenBSD and Mac OS X) there is no difference
-//!     between the two sources. (Also note that, on some systems e.g. FreeBSD, both `/dev/random`
-//!     and `/dev/urandom` may block once if the CSPRNG has not seeded yet.)
-
-#![unstable(feature = "rand", issue = "0")]
-
-use cell::RefCell;
-use fmt;
-use io;
-use mem;
-use rc::Rc;
-use sys;
-
-#[cfg(target_pointer_width = "32")]
-use core_rand::IsaacRng as IsaacWordRng;
-#[cfg(target_pointer_width = "64")]
-use core_rand::Isaac64Rng as IsaacWordRng;
-
-pub use core_rand::{Rand, Rng, SeedableRng};
-pub use core_rand::{XorShiftRng, IsaacRng, Isaac64Rng};
-pub use core_rand::reseeding;
-
-pub mod reader;
-
-/// The standard RNG. This is designed to be efficient on the current
-/// platform.
-#[derive(Copy, Clone)]
-pub struct StdRng {
-    rng: IsaacWordRng,
-}
-
-impl StdRng {
-    /// Create a randomly seeded instance of `StdRng`.
-    ///
-    /// This is a very expensive operation as it has to read
-    /// randomness from the operating system and use this in an
-    /// expensive seeding operation. If one is only generating a small
-    /// number of random numbers, or doesn't need the utmost speed for
-    /// generating each number, `thread_rng` and/or `random` may be more
-    /// appropriate.
-    ///
-    /// Reading the randomness from the OS may fail, and any error is
-    /// propagated via the `io::Result` return value.
-    pub fn new() -> io::Result<StdRng> {
-        OsRng::new().map(|mut r| StdRng { rng: r.gen() })
-    }
-}
-
-impl Rng for StdRng {
-    #[inline]
-    fn next_u32(&mut self) -> u32 {
-        self.rng.next_u32()
-    }
-
-    #[inline]
-    fn next_u64(&mut self) -> u64 {
-        self.rng.next_u64()
-    }
-}
-
-impl<'a> SeedableRng<&'a [usize]> for StdRng {
-    fn reseed(&mut self, seed: &'a [usize]) {
-        // the internal RNG can just be seeded from the above
-        // randomness.
-        self.rng.reseed(unsafe {mem::transmute(seed)})
-    }
-
-    fn from_seed(seed: &'a [usize]) -> StdRng {
-        StdRng { rng: SeedableRng::from_seed(unsafe {mem::transmute(seed)}) }
-    }
-}
-
-/// Controls how the thread-local RNG is reseeded.
-struct ThreadRngReseeder;
-
-impl reseeding::Reseeder<StdRng> for ThreadRngReseeder {
-    fn reseed(&mut self, rng: &mut StdRng) {
-        *rng = match StdRng::new() {
-            Ok(r) => r,
-            Err(e) => panic!("could not reseed thread_rng: {}", e)
-        }
-    }
-}
-const THREAD_RNG_RESEED_THRESHOLD: usize = 32_768;
-type ThreadRngInner = reseeding::ReseedingRng<StdRng, ThreadRngReseeder>;
-
-/// The thread-local RNG.
-#[derive(Clone)]
-pub struct ThreadRng {
-    rng: Rc<RefCell<ThreadRngInner>>,
-}
-
-impl fmt::Debug for ThreadRng {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.pad("ThreadRng { .. }")
-    }
-}
-
-/// Retrieve the lazily-initialized thread-local random number
-/// generator, seeded by the system. Intended to be used in method
-/// chaining style, e.g. `thread_rng().gen::<isize>()`.
-///
-/// The RNG provided will reseed itself from the operating system
-/// after generating a certain amount of randomness.
-///
-/// The internal RNG used is platform and architecture dependent, even
-/// if the operating system random number generator is rigged to give
-/// the same sequence always. If absolute consistency is required,
-/// explicitly select an RNG, e.g. `IsaacRng` or `Isaac64Rng`.
-pub fn thread_rng() -> ThreadRng {
-    // used to make space in TLS for a random number generator
-    thread_local!(static THREAD_RNG_KEY: Rc<RefCell<ThreadRngInner>> = {
-        let r = match StdRng::new() {
-            Ok(r) => r,
-            Err(e) => panic!("could not initialize thread_rng: {}", e)
-        };
-        let rng = reseeding::ReseedingRng::new(r,
-                                               THREAD_RNG_RESEED_THRESHOLD,
-                                               ThreadRngReseeder);
-        Rc::new(RefCell::new(rng))
-    });
-
-    ThreadRng { rng: THREAD_RNG_KEY.with(|t| t.clone()) }
-}
-
-impl Rng for ThreadRng {
-    fn next_u32(&mut self) -> u32 {
-        self.rng.borrow_mut().next_u32()
-    }
-
-    fn next_u64(&mut self) -> u64 {
-        self.rng.borrow_mut().next_u64()
-    }
-
-    #[inline]
-    fn fill_bytes(&mut self, bytes: &mut [u8]) {
-        self.rng.borrow_mut().fill_bytes(bytes)
-    }
-}
-
-/// A random number generator that retrieves randomness straight from
-/// the operating system. Platform sources:
-///
-/// - Unix-like systems (Linux, Android, Mac OSX): read directly from
-///   `/dev/urandom`, or from `getrandom(2)` system call if available.
-/// - Windows: calls `CryptGenRandom`, using the default cryptographic
-///   service provider with the `PROV_RSA_FULL` type.
-/// - iOS: calls SecRandomCopyBytes as /dev/(u)random is sandboxed.
-/// - OpenBSD: uses the `getentropy(2)` system call.
-///
-/// This does not block.
-pub struct OsRng(sys::rand::OsRng);
-
-impl OsRng {
-    /// Create a new `OsRng`.
-    pub fn new() -> io::Result<OsRng> {
-        sys::rand::OsRng::new().map(OsRng)
-    }
-}
-
-impl Rng for OsRng {
-    #[inline]
-    fn next_u32(&mut self) -> u32 {
-        self.0.next_u32()
-    }
-
-    #[inline]
-    fn next_u64(&mut self) -> u64 {
-        self.0.next_u64()
-    }
-
-    #[inline]
-    fn fill_bytes(&mut self, bytes: &mut [u8]) {
-        self.0.fill_bytes(bytes)
-    }
-}
-
-
-#[cfg(test)]
-mod tests {
-    use sync::mpsc::channel;
-    use rand::Rng;
-    use super::OsRng;
-    use thread;
-
-    #[test]
-    fn test_os_rng() {
-        let mut r = OsRng::new().unwrap();
-
-        r.next_u32();
-        r.next_u64();
-
-        let mut v = [0; 1000];
-        r.fill_bytes(&mut v);
-    }
-
-    #[test]
-    #[cfg_attr(target_os = "emscripten", ignore)]
-    fn test_os_rng_tasks() {
-
-        let mut txs = vec![];
-        for _ in 0..20 {
-            let (tx, rx) = channel();
-            txs.push(tx);
-
-            thread::spawn(move|| {
-                // wait until all the threads are ready to go.
-                rx.recv().unwrap();
-
-                // deschedule to attempt to interleave things as much
-                // as possible (XXX: is this a good test?)
-                let mut r = OsRng::new().unwrap();
-                thread::yield_now();
-                let mut v = [0; 1000];
-
-                for _ in 0..100 {
-                    r.next_u32();
-                    thread::yield_now();
-                    r.next_u64();
-                    thread::yield_now();
-                    r.fill_bytes(&mut v);
-                    thread::yield_now();
-                }
-            });
-        }
-
-        // start all the threads
-        for tx in &txs {
-            tx.send(()).unwrap();
-        }
-    }
-}
diff --git a/ctr-std/src/rand/reader.rs b/ctr-std/src/rand/reader.rs
deleted file mode 100644
index 08bc809..0000000
--- a/ctr-std/src/rand/reader.rs
+++ /dev/null
@@ -1,108 +0,0 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-//! A wrapper around any Read to treat it as an RNG.
-
-#![allow(dead_code)]
-
-use io::prelude::*;
-use rand::Rng;
-
-/// An RNG that reads random bytes straight from a `Read`. This will
-/// work best with an infinite reader, but this is not required.
-///
-/// # Panics
-///
-/// It will panic if it there is insufficient data to fulfill a request.
-pub struct ReaderRng<R> {
-    reader: R
-}
-
-impl<R: Read> ReaderRng<R> {
-    /// Create a new `ReaderRng` from a `Read`.
-    pub fn new(r: R) -> ReaderRng<R> {
-        ReaderRng {
-            reader: r
-        }
-    }
-}
-
-impl<R: Read> Rng for ReaderRng<R> {
-    fn next_u32(&mut self) -> u32 {
-        // This is designed for speed: reading a LE integer on a LE
-        // platform just involves blitting the bytes into the memory
-        // of the u32, similarly for BE on BE; avoiding byteswapping.
-        let mut bytes = [0; 4];
-        self.fill_bytes(&mut bytes);
-        unsafe { *(bytes.as_ptr() as *const u32) }
-    }
-    fn next_u64(&mut self) -> u64 {
-        // see above for explanation.
-        let mut bytes = [0; 8];
-        self.fill_bytes(&mut bytes);
-        unsafe { *(bytes.as_ptr() as *const u64) }
-    }
-    fn fill_bytes(&mut self, mut v: &mut [u8]) {
-        while !v.is_empty() {
-            let t = v;
-            match self.reader.read(t) {
-                Ok(0) => panic!("ReaderRng.fill_bytes: EOF reached"),
-                Ok(n) => v = t.split_at_mut(n).1,
-                Err(e) => panic!("ReaderRng.fill_bytes: {}", e),
-            }
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::ReaderRng;
-    use rand::Rng;
-
-    #[test]
-    fn test_reader_rng_u64() {
-        // transmute from the target to avoid endianness concerns.
-        let v = &[0, 0, 0, 0, 0, 0, 0, 1,
-                  0, 0, 0, 0, 0, 0, 0, 2,
-                  0, 0, 0, 0, 0, 0, 0, 3][..];
-        let mut rng = ReaderRng::new(v);
-
-        assert_eq!(rng.next_u64(), 1u64.to_be());
-        assert_eq!(rng.next_u64(), 2u64.to_be());
-        assert_eq!(rng.next_u64(), 3u64.to_be());
-    }
-    #[test]
-    fn test_reader_rng_u32() {
-        let v = &[0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 3][..];
-        let mut rng = ReaderRng::new(v);
-
-        assert_eq!(rng.next_u32(), 1u32.to_be());
-        assert_eq!(rng.next_u32(), 2u32.to_be());
-        assert_eq!(rng.next_u32(), 3u32.to_be());
-    }
-    #[test]
-    fn test_reader_rng_fill_bytes() {
-        let v = [1, 2, 3, 4, 5, 6, 7, 8];
-        let mut w = [0; 8];
-
-        let mut rng = ReaderRng::new(&v[..]);
-        rng.fill_bytes(&mut w);
-
-        assert!(v == w);
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_reader_rng_insufficient_bytes() {
-        let mut rng = ReaderRng::new(&[][..]);
-        let mut v = [0; 3];
-        rng.fill_bytes(&mut v);
-    }
-}
diff --git a/ctr-std/src/sync/once.rs b/ctr-std/src/sync/once.rs
index 1e7394c..c449315 100644
--- a/ctr-std/src/sync/once.rs
+++ b/ctr-std/src/sync/once.rs
@@ -248,7 +248,7 @@ impl Once {
     #[cold]
     fn call_inner(&'static self,
                   ignore_poisoning: bool,
-                  mut init: &mut FnMut(bool)) {
+                  init: &mut FnMut(bool)) {
         let mut state = self.state.load(Ordering::SeqCst);
 
         'outer: loop {
diff --git a/ctr-std/src/sys/unix/mod.rs b/ctr-std/src/sys/unix/mod.rs
index cd583b5..c0e4eb4 100644
--- a/ctr-std/src/sys/unix/mod.rs
+++ b/ctr-std/src/sys/unix/mod.rs
@@ -13,6 +13,8 @@
 use io::{self, ErrorKind};
 use libc;
 
+pub use self::rand::hashmap_random_keys;
+
 pub mod condvar;
 pub mod ext;
 pub mod fast_thread_local;
diff --git a/ctr-std/src/sys/unix/rand.rs b/ctr-std/src/sys/unix/rand.rs
index 39c967a..4500c9d 100644
--- a/ctr-std/src/sys/unix/rand.rs
+++ b/ctr-std/src/sys/unix/rand.rs
@@ -8,47 +8,36 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use io::{self, Error, ErrorKind};
 use mem;
-use rand::Rng;
-
-use libctru::{sslcInit, sslcExit, sslcGenerateRandomData};
-
-pub struct OsRng(());
-
-impl OsRng {
-    pub fn new() -> io::Result<OsRng> {
-        unsafe { 
-            let r = sslcInit(0); 
-            if r < 0 {
-                Err(Error::new(ErrorKind::Other, "Unable to initialize the RNG"))
-            } else {
-                Ok(OsRng(()))
-            }
-        }
-    }
-}
-
-impl Rng for OsRng {
-    fn next_u32(&mut self) -> u32 {
-        let mut v = [0; 4];
-        self.fill_bytes(&mut v);
-        unsafe { mem::transmute(v) }
-    }
-
-    fn next_u64(&mut self) -> u64 {
-        let mut v = [0; 8];
-        self.fill_bytes(&mut v);
-        unsafe { mem::transmute(v) }
-    }
-
-    fn fill_bytes(&mut self, v: &mut [u8]) {
-        unsafe { sslcGenerateRandomData(v.as_ptr() as _, v.len() as u32); }
+use slice;
+
+pub fn hashmap_random_keys() -> (u64, u64) {
+    let mut v = (0, 0);
+    unsafe {
+        let view = slice::from_raw_parts_mut(&mut v as *mut _ as *mut u8,
+                                             mem::size_of_val(&v));
+        imp::fill_bytes(view);
     }
+    return v
 }
 
-impl Drop for OsRng {
-    fn drop(&mut self) {
-        unsafe { sslcExit() }
+mod imp {
+    use libctru;
+
+    pub fn fill_bytes(v: &mut [u8]) {
+        unsafe {
+            // Initializing and de-initializing the sslC subsystem every time
+            // we initialize a hashmap is pretty dumb, but I can't think of a
+            // better method at the moment.
+            //
+            // lazy_static won't work because
+            // destructors (for closing the subsystem on exit) won't run.
+            //
+            // Perhaps overriding __appInit() and __appExit() will work,
+            // but that's an experiment for another time.
+            libctru::sslcInit(0);
+            libctru::sslcGenerateRandomData(v.as_ptr() as _, v.len() as u32);
+            libctru::sslcExit();
+        }
     }
 }