Auto merge of #35006 - Manishearth:rollup, r=Manishearth

Rollup of 7 pull requests

- Successful merges: #34965, #34972, #34975, #34976, #34977, #34988, #34989
- Failed merges:

8 files changed, 73 insertions, 30 deletions

diff --git a/src/libcollections/slice.rs b/src/libcollections/slice.rs
index 2c54dc13c8d..1f8eea56fc6 100644
--- a/src/libcollections/slice.rs
+++ b/src/libcollections/slice.rs
@@ -544,14 +544,21 @@ impl<T> [T] {
     ///
     /// # Example
     ///
-    /// Print the adjacent pairs of a slice (i.e. `[1,2]`, `[2,3]`,
-    /// `[3,4]`):
+    /// ```
+    /// let slice = ['r', 'u', 's', 't'];
+    /// let mut iter = slice.windows(2);
+    /// assert_eq!(iter.next().unwrap(), &['r', 'u']);
+    /// assert_eq!(iter.next().unwrap(), &['u', 's']);
+    /// assert_eq!(iter.next().unwrap(), &['s', 't']);
+    /// assert!(iter.next().is_none());
+    /// ```
     ///
-    /// ```rust
-    /// let v = &[1, 2, 3, 4];
-    /// for win in v.windows(2) {
-    ///     println!("{:?}", win);
-    /// }
+    /// If the slice is shorter than `size`:
+    ///
+    /// ```
+    /// let slice = ['f', 'o', 'o'];
+    /// let mut iter = slice.windows(4);
+    /// assert!(iter.next().is_none());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
diff --git a/src/libcollections/vec.rs b/src/libcollections/vec.rs
index 2d77b38879b..967baccd274 100644
--- a/src/libcollections/vec.rs
+++ b/src/libcollections/vec.rs
@@ -593,11 +593,12 @@ impl<T> Vec<T> {
     /// ```
     ///
     /// In this example, there is a memory leak since the memory locations
-    /// owned by the vector were not freed prior to the `set_len` call:
+    /// owned by the inner vectors were not freed prior to the `set_len` call:
     ///
     /// ```
-    /// let mut vec = vec!['r', 'u', 's', 't'];
-    ///
+    /// let mut vec = vec![vec![1, 0, 0],
+    ///                    vec![0, 1, 0],
+    ///                    vec![0, 0, 1]];
     /// unsafe {
     ///     vec.set_len(0);
     /// }
diff --git a/src/libcore/hash/mod.rs b/src/libcore/hash/mod.rs
index 9e3f7a4a84a..27fdbd38301 100644
--- a/src/libcore/hash/mod.rs
+++ b/src/libcore/hash/mod.rs
@@ -234,6 +234,16 @@ pub trait BuildHasher {
     type Hasher: Hasher;
 
     /// Creates a new hasher.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::hash_map::RandomState;
+    /// use std::hash::BuildHasher;
+    ///
+    /// let s = RandomState::new();
+    /// let new_s = s.build_hasher();
+    /// ```
     #[stable(since = "1.7.0", feature = "build_hasher")]
     fn build_hasher(&self) -> Self::Hasher;
 }
diff --git a/src/librustc_const_eval/eval.rs b/src/librustc_const_eval/eval.rs
index a3c707e82a0..4643686786b 100644
--- a/src/librustc_const_eval/eval.rs
+++ b/src/librustc_const_eval/eval.rs
@@ -1105,11 +1105,25 @@ fn cast_const<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, val: ConstVal, ty: ty::Ty)
         Float(f) => cast_const_float(tcx, f, ty),
         Char(c) => cast_const_int(tcx, Infer(c as u64), ty),
         Function(_) => Err(UnimplementedConstVal("casting fn pointers")),
-        ByteStr(_) => match ty.sty {
+        ByteStr(b) => match ty.sty {
             ty::TyRawPtr(_) => {
                 Err(ErrKind::UnimplementedConstVal("casting a bytestr to a raw ptr"))
             },
-            ty::TyRef(..) => Err(ErrKind::UnimplementedConstVal("casting a bytestr to slice")),
+            ty::TyRef(_, ty::TypeAndMut { ref ty, mutbl: hir::MutImmutable }) => match ty.sty {
+                ty::TyArray(ty, n) if ty == tcx.types.u8 && n == b.len() => Ok(ByteStr(b)),
+                ty::TySlice(_) => {
+                    Err(ErrKind::UnimplementedConstVal("casting a bytestr to slice"))
+                },
+                _ => Err(CannotCast),
+            },
+            _ => Err(CannotCast),
+        },
+        Str(s) => match ty.sty {
+            ty::TyRawPtr(_) => Err(ErrKind::UnimplementedConstVal("casting a str to a raw ptr")),
+            ty::TyRef(_, ty::TypeAndMut { ref ty, mutbl: hir::MutImmutable }) => match ty.sty {
+                ty::TyStr => Ok(Str(s)),
+                _ => Err(CannotCast),
+            },
             _ => Err(CannotCast),
         },
         _ => Err(CannotCast),
diff --git a/src/librustc_unicode/char.rs b/src/librustc_unicode/char.rs
index 7445ff94eb5..1ea0f8d70a8 100644
--- a/src/librustc_unicode/char.rs
+++ b/src/librustc_unicode/char.rs
@@ -392,7 +392,7 @@ impl char {
         C::len_utf16(self)
     }
 
-    /// Returns an interator over the bytes of this character as UTF-8.
+    /// Returns an iterator over the bytes of this character as UTF-8.
     ///
     /// The returned iterator also has an `as_slice()` method to view the
     /// encoded bytes as a byte slice.
@@ -415,7 +415,7 @@ impl char {
         C::encode_utf8(self)
     }
 
-    /// Returns an interator over the `u16` entries of this character as UTF-16.
+    /// Returns an iterator over the `u16` entries of this character as UTF-16.
     ///
     /// The returned iterator also has an `as_slice()` method to view the
     /// encoded form as a slice.
diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
index a03249e0063..ed5ac3bc0c1 100644
--- a/src/libstd/collections/hash/map.rs
+++ b/src/libstd/collections/hash/map.rs
@@ -1699,6 +1699,17 @@ impl<'a, K, V, S> Extend<(&'a K, &'a V)> for HashMap<K, V, S>
 /// A particular instance `RandomState` will create the same instances of
 /// `Hasher`, but the hashers created by two different `RandomState`
 /// instances are unlikely to produce the same result for the same values.
+///
+/// # Examples
+///
+/// ```
+/// use std::collections::HashMap;
+/// use std::collections::hash_map::RandomState;
+///
+/// let s = RandomState::new();
+/// let mut map = HashMap::with_hasher(s);
+/// map.insert(1, 2);
+/// ```
 #[derive(Clone)]
 #[stable(feature = "hashmap_build_hasher", since = "1.7.0")]
 pub struct RandomState {
@@ -1708,6 +1719,14 @@ pub struct RandomState {
 
 impl RandomState {
     /// Constructs a new `RandomState` that is initialized with random keys.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::collections::hash_map::RandomState;
+    ///
+    /// let s = RandomState::new();
+    /// ```
     #[inline]
     #[allow(deprecated)] // rand
     #[stable(feature = "hashmap_build_hasher", since = "1.7.0")]
diff --git a/src/libsyntax_pos/lib.rs b/src/libsyntax_pos/lib.rs
index 7dfe19452a2..c96be8fec2b 100644
--- a/src/libsyntax_pos/lib.rs
+++ b/src/libsyntax_pos/lib.rs
@@ -193,20 +193,6 @@ impl MultiSpan {
         }
     }
 
-    pub fn from_span(primary_span: Span) -> MultiSpan {
-        MultiSpan {
-            primary_spans: vec![primary_span],
-            span_labels: vec![]
-        }
-    }
-
-    pub fn from_spans(vec: Vec<Span>) -> MultiSpan {
-        MultiSpan {
-            primary_spans: vec,
-            span_labels: vec![]
-        }
-    }
-
     pub fn push_span_label(&mut self, span: Span, label: String) {
         self.span_labels.push((span, label));
     }
@@ -254,7 +240,10 @@ impl MultiSpan {
 
 impl From<Span> for MultiSpan {
     fn from(span: Span) -> MultiSpan {
-        MultiSpan::from_span(span)
+        MultiSpan {
+            primary_spans: vec![span],
+            span_labels: vec![]
+        }
     }
 }
 
diff --git a/src/test/run-pass/const-byte-str-cast.rs b/src/test/run-pass/const-byte-str-cast.rs
index 2f265b9112b..7297c71a6d6 100644
--- a/src/test/run-pass/const-byte-str-cast.rs
+++ b/src/test/run-pass/const-byte-str-cast.rs
@@ -1,4 +1,4 @@
-// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -12,4 +12,7 @@
 
 pub fn main() {
     let _ = b"x" as &[u8];
+    let _ = b"y" as &[u8; 1];
+    let _ = b"z" as *const u8;
+    let _ = "ä" as *const str;
 }