Auto merge of #49642 - kennytm:rollup, r=kennytm

Rollup of 25 pull requests

Successful merges:

 - #49179 (Handle future deprecation annotations )
 - #49512 (Add support for variant and types fields for intra links)
 - #49515 (fix targetted value background)
 - #49516 (Add missing anchor for union type fields)
 - #49532 (Add test for rustdoc ignore test)
 - #49533 (Add #[must_use] to a few standard library methods)
 - #49540 (Fix miri Discriminant() for non-ADT)
 - #49559 (Introduce Vec::resize_with method (see #41758))
 - #49570 (avoid IdxSets containing garbage above the universe length)
 - #49577 (Stabilize String::replace_range)
 - #49599 (Fix typo)
 - #49603 (Fix url for intra link provided method)
 - #49607 (Stabilize iterator methods in 1.27)
 - #49609 (run-pass/attr-stmt-expr: expand test cases)
 - #49612 (Fix "since" version for getpid feature.)
 - #49618 (Fix build error when compiling libcore for 16bit targets)
 - #49619 (tweak core::fmt docs)
 - #49637 (Stabilize parent_id())
 - #49639 (Update Cargo)
 - #49628 (Re-write the documentation index)
 - #49594 (Add some performance guidance to std::fs and std::io docs)
 - #49625 (miri: add public alloc_kind accessor)
 - #49634 (Add a test for the fix to issue #43058)
 - #49641 (Regression test for #46314)
 - #49547 (Unignore borrowck test)

Failed merges:

6 files changed, 14 insertions, 26 deletions

diff --git a/src/libcore/clone.rs b/src/libcore/clone.rs
index f8e8c69621a..58a8439162c 100644
--- a/src/libcore/clone.rs
+++ b/src/libcore/clone.rs
@@ -117,6 +117,7 @@ pub trait Clone : Sized {
     /// assert_eq!("Hello", hello.clone());
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use = "cloning is often expensive and is not expected to have side effects"]
     fn clone(&self) -> Self;
 
     /// Performs copy-assignment from `source`.
diff --git a/src/libcore/fmt/mod.rs b/src/libcore/fmt/mod.rs
index 62994ed15cc..d55219d7226 100644
--- a/src/libcore/fmt/mod.rs
+++ b/src/libcore/fmt/mod.rs
@@ -401,10 +401,9 @@ impl<'a> Arguments<'a> {
 /// safely be done, so no constructors are given and the fields are private
 /// to prevent modification.
 ///
-/// The [`format_args!`] macro will safely create an instance of this structure
-/// and pass it to a function or closure, passed as the first argument. The
-/// macro validates the format string at compile-time so usage of the [`write`]
-/// and [`format`] functions can be safely performed.
+/// The [`format_args!`] macro will safely create an instance of this structure.
+/// The macro validates the format string at compile-time so usage of the
+/// [`write`] and [`format`] functions can be safely performed.
 ///
 /// You can use the `Arguments<'a>` that [`format_args!`] returns in `Debug`
 /// and `Display` contexts as seen below. The example also shows that `Debug`
@@ -412,8 +411,8 @@ impl<'a> Arguments<'a> {
 /// in `format_args!`.
 ///
 /// ```rust
-/// let display = format!("{:?}", format_args!("{} foo {:?}", 1, 2));
-/// let debug = format!("{}", format_args!("{} foo {:?}", 1, 2));
+/// let debug = format!("{:?}", format_args!("{} foo {:?}", 1, 2));
+/// let display = format!("{}", format_args!("{} foo {:?}", 1, 2));
 /// assert_eq!("1 foo 2", display);
 /// assert_eq!(display, debug);
 /// ```
diff --git a/src/libcore/iter/iterator.rs b/src/libcore/iter/iterator.rs
index f039d1730eb..4ccf446aa63 100644
--- a/src/libcore/iter/iterator.rs
+++ b/src/libcore/iter/iterator.rs
@@ -1368,6 +1368,7 @@ pub trait Iterator {
     /// [`Result`]: ../../std/result/enum.Result.html
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[must_use = "if you really need to exhaust the iterator, consider `.for_each(drop)` instead"]
     fn collect<B: FromIterator<Self::Item>>(self) -> B where Self: Sized {
         FromIterator::from_iter(self)
     }
@@ -1446,7 +1447,6 @@ pub trait Iterator {
     /// Basic usage:
     ///
     /// ```
-    /// #![feature(iterator_try_fold)]
     /// let a = [1, 2, 3];
     ///
     /// // the checked sum of all of the elements of the array
@@ -1458,7 +1458,6 @@ pub trait Iterator {
     /// Short-circuiting:
     ///
     /// ```
-    /// #![feature(iterator_try_fold)]
     /// let a = [10, 20, 30, 100, 40, 50];
     /// let mut it = a.iter();
     ///
@@ -1472,7 +1471,7 @@ pub trait Iterator {
     /// assert_eq!(it.next(), Some(&40));
     /// ```
     #[inline]
-    #[unstable(feature = "iterator_try_fold", issue = "45594")]
+    #[stable(feature = "iterator_try_fold", since = "1.27.0")]
     fn try_fold<B, F, R>(&mut self, init: B, mut f: F) -> R where
         Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Ok=B>
     {
@@ -1495,7 +1494,6 @@ pub trait Iterator {
     /// # Examples
     ///
     /// ```
-    /// #![feature(iterator_try_fold)]
     /// use std::fs::rename;
     /// use std::io::{stdout, Write};
     /// use std::path::Path;
@@ -1512,7 +1510,7 @@ pub trait Iterator {
     /// assert_eq!(it.next(), Some("stale_bread.json"));
     /// ```
     #[inline]
-    #[unstable(feature = "iterator_try_fold", issue = "45594")]
+    #[stable(feature = "iterator_try_fold", since = "1.27.0")]
     fn try_for_each<F, R>(&mut self, mut f: F) -> R where
         Self: Sized, F: FnMut(Self::Item) -> R, R: Try<Ok=()>
     {
diff --git a/src/libcore/iter/range.rs b/src/libcore/iter/range.rs
index 72b48b56571..5d57207763e 100644
--- a/src/libcore/iter/range.rs
+++ b/src/libcore/iter/range.rs
@@ -488,6 +488,7 @@ macro_rules! try_from_unbounded {
 }
 
 // unsigned to signed (only positive bound)
+#[cfg(any(target_pointer_width = "32", target_pointer_width = "64"))]
 macro_rules! try_from_upper_bounded {
     ($($target:ty),*) => {$(
         impl PrivateTryFromUsize for $target {
diff --git a/src/libcore/iter/traits.rs b/src/libcore/iter/traits.rs
index c3aebc4fb23..ddbb5998942 100644
--- a/src/libcore/iter/traits.rs
+++ b/src/libcore/iter/traits.rs
@@ -427,7 +427,6 @@ pub trait DoubleEndedIterator: Iterator {
     /// Basic usage:
     ///
     /// ```
-    /// #![feature(iterator_try_fold)]
     /// let a = ["1", "2", "3"];
     /// let sum = a.iter()
     ///     .map(|&s| s.parse::<i32>())
@@ -438,7 +437,6 @@ pub trait DoubleEndedIterator: Iterator {
     /// Short-circuiting:
     ///
     /// ```
-    /// #![feature(iterator_try_fold)]
     /// let a = ["1", "rust", "3"];
     /// let mut it = a.iter();
     /// let sum = it
@@ -452,7 +450,7 @@ pub trait DoubleEndedIterator: Iterator {
     /// assert_eq!(it.next_back(), Some(&"1"));
     /// ```
     #[inline]
-    #[unstable(feature = "iterator_try_fold", issue = "45594")]
+    #[stable(feature = "iterator_try_fold", since = "1.27.0")]
     fn try_rfold<B, F, R>(&mut self, init: B, mut f: F) -> R where
         Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Ok=B>
     {
@@ -491,7 +489,6 @@ pub trait DoubleEndedIterator: Iterator {
     /// Basic usage:
     ///
     /// ```
-    /// #![feature(iter_rfold)]
     /// let a = [1, 2, 3];
     ///
     /// // the sum of all of the elements of a
@@ -505,7 +502,6 @@ pub trait DoubleEndedIterator: Iterator {
     /// and continuing with each element from the back until the front:
     ///
     /// ```
-    /// #![feature(iter_rfold)]
     /// let numbers = [1, 2, 3, 4, 5];
     ///
     /// let zero = "0".to_string();
@@ -517,14 +513,14 @@ pub trait DoubleEndedIterator: Iterator {
     /// assert_eq!(result, "(1 + (2 + (3 + (4 + (5 + 0)))))");
     /// ```
     #[inline]
-    #[unstable(feature = "iter_rfold", issue = "44705")]
+    #[stable(feature = "iter_rfold", since = "1.27.0")]
     fn rfold<B, F>(mut self, accum: B, mut f: F) -> B where
         Self: Sized, F: FnMut(B, Self::Item) -> B,
     {
         self.try_rfold(accum, move |acc, x| AlwaysOk(f(acc, x))).0
     }
 
-    /// Searches for an element of an iterator from the right that satisfies a predicate.
+    /// Searches for an element of an iterator from the back that satisfies a predicate.
     ///
     /// `rfind()` takes a closure that returns `true` or `false`. It applies
     /// this closure to each element of the iterator, starting at the end, and if any
@@ -547,8 +543,6 @@ pub trait DoubleEndedIterator: Iterator {
     /// Basic usage:
     ///
     /// ```
-    /// #![feature(iter_rfind)]
-    ///
     /// let a = [1, 2, 3];
     ///
     /// assert_eq!(a.iter().rfind(|&&x| x == 2), Some(&2));
@@ -559,8 +553,6 @@ pub trait DoubleEndedIterator: Iterator {
     /// Stopping at the first `true`:
     ///
     /// ```
-    /// #![feature(iter_rfind)]
-    ///
     /// let a = [1, 2, 3];
     ///
     /// let mut iter = a.iter();
@@ -571,7 +563,7 @@ pub trait DoubleEndedIterator: Iterator {
     /// assert_eq!(iter.next_back(), Some(&1));
     /// ```
     #[inline]
-    #[unstable(feature = "iter_rfind", issue = "39480")]
+    #[stable(feature = "iter_rfind", since = "1.27.0")]
     fn rfind<P>(&mut self, mut predicate: P) -> Option<Self::Item> where
         Self: Sized,
         P: FnMut(&Self::Item) -> bool
diff --git a/src/libcore/tests/lib.rs b/src/libcore/tests/lib.rs
index 6f6105553d4..de7211e718c 100644
--- a/src/libcore/tests/lib.rs
+++ b/src/libcore/tests/lib.rs
@@ -25,11 +25,8 @@
 #![feature(iterator_step_by)]
 #![cfg_attr(stage0, feature(i128_type))]
 #![cfg_attr(stage0, feature(inclusive_range_syntax))]
-#![feature(iterator_try_fold)]
 #![feature(iterator_flatten)]
 #![cfg_attr(stage0, feature(conservative_impl_trait))]
-#![feature(iter_rfind)]
-#![feature(iter_rfold)]
 #![feature(iterator_repeat_with)]
 #![feature(nonzero)]
 #![feature(pattern)]