std: Stabilize APIs for the 1.10 release

This commit applies the FCP decisions made by the libs team for the 1.10 cycle,
including both new stabilizations and deprecations. Specifically, the list of
APIs is:

Stabilized:

* `os::windows::fs::OpenOptionsExt::access_mode`
* `os::windows::fs::OpenOptionsExt::share_mode`
* `os::windows::fs::OpenOptionsExt::custom_flags`
* `os::windows::fs::OpenOptionsExt::attributes`
* `os::windows::fs::OpenOptionsExt::security_qos_flags`
* `os::unix::fs::OpenOptionsExt::custom_flags`
* `sync::Weak::new`
* `Default for sync::Weak`
* `panic::set_hook`
* `panic::take_hook`
* `panic::PanicInfo`
* `panic::PanicInfo::payload`
* `panic::PanicInfo::location`
* `panic::Location`
* `panic::Location::file`
* `panic::Location::line`
* `ffi::CStr::from_bytes_with_nul`
* `ffi::CStr::from_bytes_with_nul_unchecked`
* `ffi::FromBytesWithNulError`
* `fs::Metadata::modified`
* `fs::Metadata::accessed`
* `fs::Metadata::created`
* `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange`
* `sync::atomic::Atomic{Usize,Isize,Bool,Ptr}::compare_exchange_weak`
* `collections::{btree,hash}_map::{Occupied,Vacant,}Entry::key`
* `os::unix::net::{UnixStream, UnixListener, UnixDatagram, SocketAddr}`
* `SocketAddr::is_unnamed`
* `SocketAddr::as_pathname`
* `UnixStream::connect`
* `UnixStream::pair`
* `UnixStream::try_clone`
* `UnixStream::local_addr`
* `UnixStream::peer_addr`
* `UnixStream::set_read_timeout`
* `UnixStream::set_write_timeout`
* `UnixStream::read_timeout`
* `UnixStream::write_Timeout`
* `UnixStream::set_nonblocking`
* `UnixStream::take_error`
* `UnixStream::shutdown`
* Read/Write/RawFd impls for `UnixStream`
* `UnixListener::bind`
* `UnixListener::accept`
* `UnixListener::try_clone`
* `UnixListener::local_addr`
* `UnixListener::set_nonblocking`
* `UnixListener::take_error`
* `UnixListener::incoming`
* RawFd impls for `UnixListener`
* `UnixDatagram::bind`
* `UnixDatagram::unbound`
* `UnixDatagram::pair`
* `UnixDatagram::connect`
* `UnixDatagram::try_clone`
* `UnixDatagram::local_addr`
* `UnixDatagram::peer_addr`
* `UnixDatagram::recv_from`
* `UnixDatagram::recv`
* `UnixDatagram::send_to`
* `UnixDatagram::send`
* `UnixDatagram::set_read_timeout`
* `UnixDatagram::set_write_timeout`
* `UnixDatagram::read_timeout`
* `UnixDatagram::write_timeout`
* `UnixDatagram::set_nonblocking`
* `UnixDatagram::take_error`
* `UnixDatagram::shutdown`
* RawFd impls for `UnixDatagram`
* `{BTree,Hash}Map::values_mut`
* `<[_]>::binary_search_by_key`

Deprecated:

* `StaticCondvar` - this, and all other static synchronization primitives
                    below, are usable today through the lazy-static crate on
                    stable Rust today. Additionally, we'd like the non-static
                    versions to be directly usable in a static context one day,
                    so they're unlikely to be the final forms of the APIs in any
                    case.
* `CONDVAR_INIT`
* `StaticMutex`
* `MUTEX_INIT`
* `StaticRwLock`
* `RWLOCK_INIT`
* `iter::Peekable::is_empty`

Closes #27717
Closes #27720
cc #27784 (but encode methods still exist)
Closes #30014
Closes #30425
Closes #30449
Closes #31190
Closes #31399
Closes #31767
Closes #32111
Closes #32281
Closes #32312
Closes #32551
Closes #33018

3 files changed, 63 insertions, 58 deletions

diff --git a/src/liballoc/arc.rs b/src/liballoc/arc.rs
index 4aba567fa1c..d0a51e320cc 100644
--- a/src/liballoc/arc.rs
+++ b/src/liballoc/arc.rs
@@ -592,6 +592,31 @@ impl<T: ?Sized> Drop for Arc<T> {
     }
 }
 
+impl<T> Weak<T> {
+    /// Constructs a new `Weak<T>` without an accompanying instance of T.
+    ///
+    /// This allocates memory for T, but does not initialize it. Calling
+    /// Weak<T>::upgrade() on the return value always gives None.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::sync::Weak;
+    ///
+    /// let empty: Weak<i64> = Weak::new();
+    /// ```
+    #[stable(feature = "downgraded_weak", since = "1.10.0")]
+    pub fn new() -> Weak<T> {
+        unsafe {
+            Weak { ptr: Shared::new(Box::into_raw(box ArcInner {
+                strong: atomic::AtomicUsize::new(0),
+                weak: atomic::AtomicUsize::new(1),
+                data: uninitialized(),
+            }))}
+        }
+    }
+}
+
 impl<T: ?Sized> Weak<T> {
     /// Upgrades a weak reference to a strong reference.
     ///
@@ -682,6 +707,13 @@ impl<T: ?Sized> Clone for Weak<T> {
     }
 }
 
+#[stable(feature = "downgraded_weak", since = "1.10.0")]
+impl<T> Default for Weak<T> {
+    fn default() -> Weak<T> {
+        Weak::new()
+    }
+}
+
 #[stable(feature = "arc_weak", since = "1.4.0")]
 impl<T: ?Sized> Drop for Weak<T> {
     /// Drops the `Weak<T>`.
@@ -907,35 +939,6 @@ impl<T> From<T> for Arc<T> {
     }
 }
 
-impl<T> Weak<T> {
-    /// Constructs a new `Weak<T>` without an accompanying instance of T.
-    ///
-    /// This allocates memory for T, but does not initialize it. Calling
-    /// Weak<T>::upgrade() on the return value always gives None.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(downgraded_weak)]
-    ///
-    /// use std::sync::Weak;
-    ///
-    /// let empty: Weak<i64> = Weak::new();
-    /// ```
-    #[unstable(feature = "downgraded_weak",
-               reason = "recently added",
-               issue = "30425")]
-    pub fn new() -> Weak<T> {
-        unsafe {
-            Weak { ptr: Shared::new(Box::into_raw(box ArcInner {
-                strong: atomic::AtomicUsize::new(0),
-                weak: atomic::AtomicUsize::new(1),
-                data: uninitialized(),
-            }))}
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use std::clone::Clone;
diff --git a/src/liballoc/lib.rs b/src/liballoc/lib.rs
index c2dad9a1ae4..0293d5402c4 100644
--- a/src/liballoc/lib.rs
+++ b/src/liballoc/lib.rs
@@ -90,7 +90,6 @@
 #![feature(unique)]
 #![feature(unsafe_no_drop_flag, filling_drop)]
 #![feature(unsize)]
-#![feature(extended_compare_and_swap)]
 
 #![cfg_attr(not(test), feature(raw, fn_traits, placement_new_protocol))]
 #![cfg_attr(test, feature(test, box_heap))]
diff --git a/src/liballoc/rc.rs b/src/liballoc/rc.rs
index c2f0a961327..b92f5af05e3 100644
--- a/src/liballoc/rc.rs
+++ b/src/liballoc/rc.rs
@@ -720,6 +720,33 @@ impl<T: ?Sized> !marker::Sync for Weak<T> {}
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Weak<U>> for Weak<T> {}
 
+impl<T> Weak<T> {
+    /// Constructs a new `Weak<T>` without an accompanying instance of T.
+    ///
+    /// This allocates memory for T, but does not initialize it. Calling
+    /// Weak<T>::upgrade() on the return value always gives None.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::rc::Weak;
+    ///
+    /// let empty: Weak<i64> = Weak::new();
+    /// ```
+    #[stable(feature = "downgraded_weak", since = "1.10.0")]
+    pub fn new() -> Weak<T> {
+        unsafe {
+            Weak {
+                ptr: Shared::new(Box::into_raw(box RcBox {
+                    strong: Cell::new(0),
+                    weak: Cell::new(1),
+                    value: uninitialized(),
+                })),
+            }
+        }
+    }
+}
+
 impl<T: ?Sized> Weak<T> {
     /// Upgrades a weak reference to a strong reference.
     ///
@@ -823,34 +850,10 @@ impl<T: ?Sized + fmt::Debug> fmt::Debug for Weak<T> {
     }
 }
 
-impl<T> Weak<T> {
-    /// Constructs a new `Weak<T>` without an accompanying instance of T.
-    ///
-    /// This allocates memory for T, but does not initialize it. Calling
-    /// Weak<T>::upgrade() on the return value always gives None.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(downgraded_weak)]
-    ///
-    /// use std::rc::Weak;
-    ///
-    /// let empty: Weak<i64> = Weak::new();
-    /// ```
-    #[unstable(feature = "downgraded_weak",
-               reason = "recently added",
-               issue="30425")]
-    pub fn new() -> Weak<T> {
-        unsafe {
-            Weak {
-                ptr: Shared::new(Box::into_raw(box RcBox {
-                    strong: Cell::new(0),
-                    weak: Cell::new(1),
-                    value: uninitialized(),
-                })),
-            }
-        }
+#[stable(feature = "downgraded_weak", since = "1.10.0")]
+impl<T> Default for Weak<T> {
+    fn default() -> Weak<T> {
+        Weak::new()
     }
 }