Auto merge of #57087 - Centril:rollup, r=Centril

Rollup of 14 pull requests

Successful merges:

 - #56188 (enum type instead of variant suggestion unification )
 - #56342 (Improve docs for collecting into `Option`s)
 - #56916 (Fix mutable references in `static mut`)
 - #56917 (Simplify MIR generation for logical operations)
 - #56939 (Pin stabilization)
 - #56953 (Mark tuple structs as live if their constructors are used)
 - #56964 (Remove `TokenStream::JointTree`.)
 - #56966 (Correct strings for raw pointer deref and array access suggestions)
 - #57020 (Point to cause of `fn` expected return type)
 - #57032 (fix deprecation warnings in liballoc benches)
 - #57053 (Fix alignment for array indexing)
 - #57062 (Fix a comment)
 - #57067 (Stabilize min_const_unsafe_fn in 1.33)
 - #57078 (Ignore two tests on s390x)

Failed merges:

r? @ghost

Author: bors

Cargo.lock

@@ -18,6 +18,7 @@ dependencies = [
  "compiler_builtins 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_xorshift 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]

src/liballoc/Cargo.toml

@@ -15,6 +15,7 @@ compiler_builtins = { version = "0.1.0", features = ['rustc-dep-of-std'] }
 
 [dev-dependencies]
 rand = "0.6"
+rand_xorshift = "0.1"
 
 [[test]]
 name = "collectionstests"

src/liballoc/benches/btree/map.rs

@@ -12,7 +12,7 @@
 use std::iter::Iterator;
 use std::vec::Vec;
 use std::collections::BTreeMap;
-use rand::{Rng, thread_rng};
+use rand::{Rng, seq::SliceRandom, thread_rng};
 use test::{Bencher, black_box};
 
 macro_rules! map_insert_rand_bench {
@@ -78,7 +78,7 @@ macro_rules! map_find_rand_bench {
                 map.insert(k, k);
             }
 
-            rng.shuffle(&mut keys);
+            keys.shuffle(&mut rng);
 
             // measure
             let mut i = 0;

src/liballoc/benches/lib.rs

@@ -13,6 +13,7 @@
 #![feature(test)]
 
 extern crate rand;
+extern crate rand_xorshift;
 extern crate test;
 
 mod btree;

src/liballoc/benches/slice.rs

@@ -12,8 +12,9 @@ use rand::{thread_rng};
 use std::mem;
 use std::ptr;
 
-use rand::{Rng, SeedableRng, XorShiftRng};
+use rand::{Rng, SeedableRng};
 use rand::distributions::{Standard, Alphanumeric};
+use rand_xorshift::XorShiftRng;
 use test::{Bencher, black_box};
 
 #[bench]

src/liballoc/benches/str.rs

@@ -274,11 +274,11 @@ make_test!(split_a_str, s, s.split("a").count());
 make_test!(trim_ascii_char, s, {
     s.trim_matches(|c: char| c.is_ascii())
 });
-make_test!(trim_left_ascii_char, s, {
-    s.trim_left_matches(|c: char| c.is_ascii())
+make_test!(trim_start_ascii_char, s, {
+    s.trim_start_matches(|c: char| c.is_ascii())
 });
-make_test!(trim_right_ascii_char, s, {
-    s.trim_right_matches(|c: char| c.is_ascii())
+make_test!(trim_end_ascii_char, s, {
+    s.trim_end_matches(|c: char| c.is_ascii())
 });
 
 make_test!(find_underscore_char, s, s.find('_'));

src/liballoc/boxed.rs

@@ -111,9 +111,11 @@ impl<T> Box<T> {
         box x
     }
 
-    #[unstable(feature = "pin", issue = "49150")]
+    /// Constructs a new `Pin<Box<T>>`. If `T` does not implement `Unpin`, then
+    /// `x` will be pinned in memory and unable to be moved.
+    #[stable(feature = "pin", since = "1.33.0")]
     #[inline(always)]
-    pub fn pinned(x: T) -> Pin<Box<T>> {
+    pub fn pin(x: T) -> Pin<Box<T>> {
         (box x).into()
     }
 }
@@ -446,7 +448,7 @@ impl<T> From<T> for Box<T> {
     }
 }
 
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl<T> From<Box<T>> for Pin<Box<T>> {
     fn from(boxed: Box<T>) -> Self {
         // It's not possible to move or replace the insides of a `Pin<Box<T>>`
@@ -813,7 +815,7 @@ impl<T: ?Sized> AsMut<T> for Box<T> {
  *  implementation of `Unpin` (where `T: Unpin`) would be valid/safe, and
  *  could have a method to project a Pin<T> from it.
  */
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl<T: ?Sized> Unpin for Box<T> { }
 
 #[unstable(feature = "generator_trait", issue = "43122")]

src/liballoc/lib.rs

@@ -102,7 +102,6 @@
 #![feature(nll)]
 #![feature(optin_builtin_traits)]
 #![feature(pattern)]
-#![feature(pin)]
 #![feature(ptr_internals)]
 #![feature(ptr_offset_from)]
 #![feature(rustc_attrs)]

src/liballoc/rc.rs

@@ -325,8 +325,10 @@ impl<T> Rc<T> {
         }
     }
 
-    #[unstable(feature = "pin", issue = "49150")]
-    pub fn pinned(value: T) -> Pin<Rc<T>> {
+    /// Constructs a new `Pin<Rc<T>>`. If `T` does not implement `Unpin`, then
+    /// `value` will be pinned in memory and unable to be moved.
+    #[stable(feature = "pin", since = "1.33.0")]
+    pub fn pin(value: T) -> Pin<Rc<T>> {
         unsafe { Pin::new_unchecked(Rc::new(value)) }
     }
 
@@ -1934,5 +1936,5 @@ impl<T: ?Sized> AsRef<T> for Rc<T> {
     }
 }
 
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl<T: ?Sized> Unpin for Rc<T> { }

src/liballoc/sync.rs

@@ -303,8 +303,10 @@ impl<T> Arc<T> {
         Arc { ptr: Box::into_raw_non_null(x), phantom: PhantomData }
     }
 
-    #[unstable(feature = "pin", issue = "49150")]
-    pub fn pinned(data: T) -> Pin<Arc<T>> {
+    /// Constructs a new `Pin<Arc<T>>`. If `T` does not implement `Unpin`, then
+    /// `data` will be pinned in memory and unable to be moved.
+    #[stable(feature = "pin", since = "1.33.0")]
+    pub fn pin(data: T) -> Pin<Arc<T>> {
         unsafe { Pin::new_unchecked(Arc::new(data)) }
     }
 
@@ -2050,5 +2052,5 @@ impl<T: ?Sized> AsRef<T> for Arc<T> {
     }
 }
 
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl<T: ?Sized> Unpin for Arc<T> { }

src/libcore/future/future.rs

@@ -120,7 +120,7 @@ impl<'a, F: ?Sized + Future + Unpin> Future for &'a mut F {
 
 impl<P> Future for Pin<P>
 where
-    P: ops::DerefMut,
+    P: Unpin + ops::DerefMut,
     P::Target: Future,
 {
     type Output = <<P as ops::Deref>::Target as Future>::Output;

src/libcore/marker.rs

@@ -621,7 +621,6 @@ unsafe impl<T: ?Sized> Freeze for &mut T {}
 /// So this, for example, can only be done on types implementing `Unpin`:
 ///
 /// ```rust
-/// #![feature(pin)]
 /// use std::mem::replace;
 /// use std::pin::Pin;
 ///
@@ -637,23 +636,23 @@ unsafe impl<T: ?Sized> Freeze for &mut T {}
 /// [`replace`]: ../../std/mem/fn.replace.html
 /// [`Pin`]: ../pin/struct.Pin.html
 /// [`pin module`]: ../../std/pin/index.html
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 pub auto trait Unpin {}
 
 /// A marker type which does not implement `Unpin`.
 ///
 /// If a type contains a `PhantomPinned`, it will not implement `Unpin` by default.
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
 pub struct PhantomPinned;
 
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl !Unpin for PhantomPinned {}
 
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl<'a, T: ?Sized + 'a> Unpin for &'a T {}
 
-#[unstable(feature = "pin", issue = "49150")]
+#[stable(feature = "pin", since = "1.33.0")]
 impl<'a, T: ?Sized + 'a> Unpin for &'a mut T {}
 
 /// Implementations of `Copy` for primitive types.

src/libcore/option.rs

@@ -273,7 +273,7 @@ impl<T> Option<T> {
 
     /// Converts from `Pin<&Option<T>>` to `Option<Pin<&T>>`
     #[inline]
-    #[unstable(feature = "pin", issue = "49150")]
+    #[stable(feature = "pin", since = "1.33.0")]
     pub fn as_pin_ref<'a>(self: Pin<&'a Option<T>>) -> Option<Pin<&'a T>> {
         unsafe {
             Pin::get_ref(self).as_ref().map(|x| Pin::new_unchecked(x))
@@ -282,10 +282,10 @@ impl<T> Option<T> {
 
     /// Converts from `Pin<&mut Option<T>>` to `Option<Pin<&mut T>>`
     #[inline]
-    #[unstable(feature = "pin", issue = "49150")]
+    #[stable(feature = "pin", since = "1.33.0")]
     pub fn as_pin_mut<'a>(self: Pin<&'a mut Option<T>>) -> Option<Pin<&'a mut T>> {
         unsafe {
-            Pin::get_mut_unchecked(self).as_mut().map(|x| Pin::new_unchecked(x))
+            Pin::get_unchecked_mut(self).as_mut().map(|x| Pin::new_unchecked(x))
         }
     }
 
@@ -1253,20 +1253,42 @@ impl<A, V: FromIterator<A>> FromIterator<Option<A>> for Option<V> {
     /// returned. Should no [`None`][Option::None] occur, a container with the
     /// values of each [`Option`] is returned.
     ///
-    /// Here is an example which increments every integer in a vector,
-    /// checking for overflow:
+    /// # Examples
+    ///
+    /// Here is an example which increments every integer in a vector.
+    /// `We use the checked variant of `add` that returns `None` when the
+    /// calculation would result in an overflow.
     ///
     /// ```
-    /// use std::u16;
+    /// let items = vec![0_u16, 1, 2];
+    ///
+    /// let res: Option<Vec<u16>> = items
+    ///     .iter()
+    ///     .map(|x| x.checked_add(1))
+    ///     .collect();
     ///
-    /// let v = vec![1, 2];
-    /// let res: Option<Vec<u16>> = v.iter().map(|&x: &u16|
-    ///     if x == u16::MAX { None }
-    ///     else { Some(x + 1) }
-    /// ).collect();
-    /// assert!(res == Some(vec![2, 3]));
+    /// assert_eq!(res, Some(vec![1, 2, 3]));
     /// ```
     ///
+    /// As you can see, this will return the expected, valid items.
+    ///
+    /// Here is another example that tries to subtract one from another list
+    /// of integers, this time checking for underflow:
+    ///
+    /// ```
+    /// let items = vec![2_u16, 1, 0];
+    ///
+    /// let res: Option<Vec<u16>> = items
+    ///     .iter()
+    ///     .map(|x| x.checked_sub(1))
+    ///     .collect();
+    ///
+    /// assert_eq!(res, None);
+    /// ```
+    ///
+    /// Since the last element is zero, it would underflow. Thus, the resulting
+    /// value is `None`.
+    ///
     /// [`Iterator`]: ../iter/trait.Iterator.html
     #[inline]
     fn from_iter<I: IntoIterator<Item=Option<A>>>(iter: I) -> Option<V> {