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-rw-r--r--src/liballoc/binary_heap.rs66
-rw-r--r--src/liballoc/boxed.rs151
-rw-r--r--src/liballoc/lib.rs12
-rw-r--r--src/liballoc/linked_list.rs178
-rw-r--r--src/liballoc/tests/binary_heap.rs20
-rw-r--r--src/liballoc/tests/lib.rs2
-rw-r--r--src/liballoc/tests/vec.rs20
-rw-r--r--src/liballoc/tests/vec_deque.rs22
-rw-r--r--src/liballoc/vec.rs76
-rw-r--r--src/liballoc/vec_deque.rs144
10 files changed, 11 insertions, 680 deletions
diff --git a/src/liballoc/binary_heap.rs b/src/liballoc/binary_heap.rs
index f6a666b599b..668b61c51d8 100644
--- a/src/liballoc/binary_heap.rs
+++ b/src/liballoc/binary_heap.rs
@@ -155,7 +155,7 @@
 #![allow(missing_docs)]
 #![stable(feature = "rust1", since = "1.0.0")]
 
-use core::ops::{Deref, DerefMut, Place, Placer, InPlace};
+use core::ops::{Deref, DerefMut};
 use core::iter::{FromIterator, FusedIterator};
 use core::mem::{swap, size_of};
 use core::ptr;
@@ -1195,67 +1195,3 @@ impl<'a, T: 'a + Ord + Copy> Extend<&'a T> for BinaryHeap<T> {
         self.extend(iter.into_iter().cloned());
     }
 }
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-pub struct BinaryHeapPlace<'a, T: 'a>
-where T: Clone + Ord {
-    heap: *mut BinaryHeap<T>,
-    place: vec::PlaceBack<'a, T>,
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T: Clone + Ord + fmt::Debug> fmt::Debug for BinaryHeapPlace<'a, T> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.debug_tuple("BinaryHeapPlace")
-         .field(&self.place)
-         .finish()
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T: 'a> Placer<T> for &'a mut BinaryHeap<T>
-where T: Clone + Ord {
-    type Place = BinaryHeapPlace<'a, T>;
-
-    fn make_place(self) -> Self::Place {
-        let ptr = self as *mut BinaryHeap<T>;
-        let place = Placer::make_place(self.data.place_back());
-        BinaryHeapPlace {
-            heap: ptr,
-            place,
-        }
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-unsafe impl<'a, T> Place<T> for BinaryHeapPlace<'a, T>
-where T: Clone + Ord {
-    fn pointer(&mut self) -> *mut T {
-        self.place.pointer()
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> InPlace<T> for BinaryHeapPlace<'a, T>
-where T: Clone + Ord {
-    type Owner = &'a T;
-
-    unsafe fn finalize(self) -> &'a T {
-        self.place.finalize();
-
-        let heap: &mut BinaryHeap<T> = &mut *self.heap;
-        let len = heap.len();
-        let i = heap.sift_up(0, len - 1);
-        heap.data.get_unchecked(i)
-    }
-}
diff --git a/src/liballoc/boxed.rs b/src/liballoc/boxed.rs
index e59a6e9fdea..4f9dc61ce19 100644
--- a/src/liballoc/boxed.rs
+++ b/src/liballoc/boxed.rs
@@ -55,7 +55,6 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
-use heap::Heap;
 use raw_vec::RawVec;
 
 use core::any::Any;
@@ -63,47 +62,14 @@ use core::borrow;
 use core::cmp::Ordering;
 use core::fmt;
 use core::hash::{Hash, Hasher};
-use core::heap::{Alloc, Layout};
 use core::iter::FusedIterator;
-use core::marker::{self, Unpin, Unsize};
+use core::marker::{Unpin, Unsize};
 use core::mem::{self, Pin};
 use core::ops::{CoerceUnsized, Deref, DerefMut, Generator, GeneratorState};
-use core::ops::{BoxPlace, Boxed, InPlace, Place, Placer};
 use core::ptr::{self, NonNull, Unique};
 use core::convert::From;
 use str::from_boxed_utf8_unchecked;
 
-/// A value that represents the heap. This is the default place that the `box`
-/// keyword allocates into when no place is supplied.
-///
-/// The following two examples are equivalent:
-///
-/// ```
-/// #![feature(box_heap)]
-///
-/// #![feature(box_syntax, placement_in_syntax)]
-/// use std::boxed::HEAP;
-///
-/// fn main() {
-///     let foo: Box<i32> = in HEAP { 5 };
-///     let foo = box 5;
-/// }
-/// ```
-#[unstable(feature = "box_heap",
-           reason = "may be renamed; uncertain about custom allocator design",
-           issue = "27779")]
-pub const HEAP: ExchangeHeapSingleton = ExchangeHeapSingleton { _force_singleton: () };
-
-/// This the singleton type used solely for `boxed::HEAP`.
-#[unstable(feature = "box_heap",
-           reason = "may be renamed; uncertain about custom allocator design",
-           issue = "27779")]
-#[allow(missing_debug_implementations)]
-#[derive(Copy, Clone)]
-pub struct ExchangeHeapSingleton {
-    _force_singleton: (),
-}
-
 /// A pointer type for heap allocation.
 ///
 /// See the [module-level documentation](../../std/boxed/index.html) for more.
@@ -112,121 +78,6 @@ pub struct ExchangeHeapSingleton {
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Box<T: ?Sized>(Unique<T>);
 
-/// `IntermediateBox` represents uninitialized backing storage for `Box`.
-///
-/// FIXME (pnkfelix): Ideally we would just reuse `Box<T>` instead of
-/// introducing a separate `IntermediateBox<T>`; but then you hit
-/// issues when you e.g. attempt to destructure an instance of `Box`,
-/// since it is a lang item and so it gets special handling by the
-/// compiler.  Easier just to make this parallel type for now.
-///
-/// FIXME (pnkfelix): Currently the `box` protocol only supports
-/// creating instances of sized types. This IntermediateBox is
-/// designed to be forward-compatible with a future protocol that
-/// supports creating instances of unsized types; that is why the type
-/// parameter has the `?Sized` generalization marker, and is also why
-/// this carries an explicit size. However, it probably does not need
-/// to carry the explicit alignment; that is just a work-around for
-/// the fact that the `align_of` intrinsic currently requires the
-/// input type to be Sized (which I do not think is strictly
-/// necessary).
-#[unstable(feature = "placement_in",
-           reason = "placement box design is still being worked out.",
-           issue = "27779")]
-#[allow(missing_debug_implementations)]
-pub struct IntermediateBox<T: ?Sized> {
-    ptr: *mut u8,
-    layout: Layout,
-    marker: marker::PhantomData<*mut T>,
-}
-
-#[unstable(feature = "placement_in",
-           reason = "placement box design is still being worked out.",
-           issue = "27779")]
-unsafe impl<T> Place<T> for IntermediateBox<T> {
-    fn pointer(&mut self) -> *mut T {
-        self.ptr as *mut T
-    }
-}
-
-unsafe fn finalize<T>(b: IntermediateBox<T>) -> Box<T> {
-    let p = b.ptr as *mut T;
-    mem::forget(b);
-    Box::from_raw(p)
-}
-
-fn make_place<T>() -> IntermediateBox<T> {
-    let layout = Layout::new::<T>();
-
-    let p = if layout.size() == 0 {
-        mem::align_of::<T>() as *mut u8
-    } else {
-        unsafe {
-            Heap.alloc(layout.clone()).unwrap_or_else(|err| {
-                Heap.oom(err)
-            })
-        }
-    };
-
-    IntermediateBox {
-        ptr: p,
-        layout,
-        marker: marker::PhantomData,
-    }
-}
-
-#[unstable(feature = "placement_in",
-           reason = "placement box design is still being worked out.",
-           issue = "27779")]
-impl<T> BoxPlace<T> for IntermediateBox<T> {
-    fn make_place() -> IntermediateBox<T> {
-        make_place()
-    }
-}
-
-#[unstable(feature = "placement_in",
-           reason = "placement box design is still being worked out.",
-           issue = "27779")]
-impl<T> InPlace<T> for IntermediateBox<T> {
-    type Owner = Box<T>;
-    unsafe fn finalize(self) -> Box<T> {
-        finalize(self)
-    }
-}
-
-#[unstable(feature = "placement_new_protocol", issue = "27779")]
-impl<T> Boxed for Box<T> {
-    type Data = T;
-    type Place = IntermediateBox<T>;
-    unsafe fn finalize(b: IntermediateBox<T>) -> Box<T> {
-        finalize(b)
-    }
-}
-
-#[unstable(feature = "placement_in",
-           reason = "placement box design is still being worked out.",
-           issue = "27779")]
-impl<T> Placer<T> for ExchangeHeapSingleton {
-    type Place = IntermediateBox<T>;
-
-    fn make_place(self) -> IntermediateBox<T> {
-        make_place()
-    }
-}
-
-#[unstable(feature = "placement_in",
-           reason = "placement box design is still being worked out.",
-           issue = "27779")]
-impl<T: ?Sized> Drop for IntermediateBox<T> {
-    fn drop(&mut self) {
-        if self.layout.size() > 0 {
-            unsafe {
-                Heap.dealloc(self.ptr, self.layout.clone())
-            }
-        }
-    }
-}
-
 impl<T> Box<T> {
     /// Allocates memory on the heap and then places `x` into it.
     ///
diff --git a/src/liballoc/lib.rs b/src/liballoc/lib.rs
index e6a311041f5..2fad3b0bad4 100644
--- a/src/liballoc/lib.rs
+++ b/src/liballoc/lib.rs
@@ -76,7 +76,6 @@
 #![deny(missing_debug_implementations)]
 
 #![cfg_attr(test, allow(deprecated))] // rand
-#![cfg_attr(test, feature(placement_in))]
 #![cfg_attr(not(test), feature(core_float))]
 #![cfg_attr(not(test), feature(exact_size_is_empty))]
 #![cfg_attr(not(test), feature(generator_trait))]
@@ -108,8 +107,6 @@
 #![feature(optin_builtin_traits)]
 #![feature(pattern)]
 #![feature(pin)]
-#![feature(placement_in_syntax)]
-#![feature(placement_new_protocol)]
 #![feature(ptr_internals)]
 #![feature(rustc_attrs)]
 #![feature(slice_get_slice)]
@@ -128,8 +125,8 @@
 #![feature(pointer_methods)]
 #![feature(inclusive_range_fields)]
 
-#![cfg_attr(not(test), feature(fn_traits, placement_new_protocol, swap_with_slice, i128))]
-#![cfg_attr(test, feature(test, box_heap))]
+#![cfg_attr(not(test), feature(fn_traits, swap_with_slice, i128))]
+#![cfg_attr(test, feature(test))]
 
 // Allow testing this library
 
@@ -159,13 +156,12 @@ pub mod heap;
 
 // Need to conditionally define the mod from `boxed.rs` to avoid
 // duplicating the lang-items when building in test cfg; but also need
-// to allow code to have `use boxed::HEAP;`
-// and `use boxed::Box;` declarations.
+// to allow code to have `use boxed::Box;` declarations.
 #[cfg(not(test))]
 pub mod boxed;
 #[cfg(test)]
 mod boxed {
-    pub use std::boxed::{Box, IntermediateBox, HEAP};
+    pub use std::boxed::Box;
 }
 #[cfg(test)]
 mod boxed_test;
diff --git a/src/liballoc/linked_list.rs b/src/liballoc/linked_list.rs
index 097d2e414f5..129b3bc6764 100644
--- a/src/liballoc/linked_list.rs
+++ b/src/liballoc/linked_list.rs
@@ -28,10 +28,9 @@ use core::hash::{Hasher, Hash};
 use core::iter::{FromIterator, FusedIterator};
 use core::marker::PhantomData;
 use core::mem;
-use core::ops::{BoxPlace, InPlace, Place, Placer};
-use core::ptr::{self, NonNull};
+use core::ptr::NonNull;
 
-use boxed::{Box, IntermediateBox};
+use boxed::Box;
 use super::SpecExtend;
 
 /// A doubly-linked list with owned nodes.
@@ -786,62 +785,6 @@ impl<T> LinkedList<T> {
             old_len: old_len,
         }
     }
-
-    /// Returns a place for insertion at the front of the list.
-    ///
-    /// Using this method with placement syntax is equivalent to
-    /// [`push_front`](#method.push_front), but may be more efficient.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(collection_placement)]
-    /// #![feature(placement_in_syntax)]
-    ///
-    /// use std::collections::LinkedList;
-    ///
-    /// let mut list = LinkedList::new();
-    /// list.front_place() <- 2;
-    /// list.front_place() <- 4;
-    /// assert!(list.iter().eq(&[4, 2]));
-    /// ```
-    #[unstable(feature = "collection_placement",
-               reason = "method name and placement protocol are subject to change",
-               issue = "30172")]
-    pub fn front_place(&mut self) -> FrontPlace<T> {
-        FrontPlace {
-            list: self,
-            node: IntermediateBox::make_place(),
-        }
-    }
-
-    /// Returns a place for insertion at the back of the list.
-    ///
-    /// Using this method with placement syntax is equivalent to [`push_back`](#method.push_back),
-    /// but may be more efficient.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(collection_placement)]
-    /// #![feature(placement_in_syntax)]
-    ///
-    /// use std::collections::LinkedList;
-    ///
-    /// let mut list = LinkedList::new();
-    /// list.back_place() <- 2;
-    /// list.back_place() <- 4;
-    /// assert!(list.iter().eq(&[2, 4]));
-    /// ```
-    #[unstable(feature = "collection_placement",
-               reason = "method name and placement protocol are subject to change",
-               issue = "30172")]
-    pub fn back_place(&mut self) -> BackPlace<T> {
-        BackPlace {
-            list: self,
-            node: IntermediateBox::make_place(),
-        }
-    }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -1242,123 +1185,6 @@ impl<T: Hash> Hash for LinkedList<T> {
     }
 }
 
-unsafe fn finalize<T>(node: IntermediateBox<Node<T>>) -> Box<Node<T>> {
-    let mut node = node.finalize();
-    ptr::write(&mut node.next, None);
-    ptr::write(&mut node.prev, None);
-    node
-}
-
-/// A place for insertion at the front of a `LinkedList`.
-///
-/// See [`LinkedList::front_place`](struct.LinkedList.html#method.front_place) for details.
-#[must_use = "places do nothing unless written to with `<-` syntax"]
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-pub struct FrontPlace<'a, T: 'a> {
-    list: &'a mut LinkedList<T>,
-    node: IntermediateBox<Node<T>>,
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-impl<'a, T: 'a + fmt::Debug> fmt::Debug for FrontPlace<'a, T> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.debug_tuple("FrontPlace")
-         .field(&self.list)
-         .finish()
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> Placer<T> for FrontPlace<'a, T> {
-    type Place = Self;
-
-    fn make_place(self) -> Self {
-        self
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-unsafe impl<'a, T> Place<T> for FrontPlace<'a, T> {
-    fn pointer(&mut self) -> *mut T {
-        unsafe { &mut (*self.node.pointer()).element }
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> InPlace<T> for FrontPlace<'a, T> {
-    type Owner = ();
-
-    unsafe fn finalize(self) {
-        let FrontPlace { list, node } = self;
-        list.push_front_node(finalize(node));
-    }
-}
-
-/// A place for insertion at the back of a `LinkedList`.
-///
-/// See [`LinkedList::back_place`](struct.LinkedList.html#method.back_place) for details.
-#[must_use = "places do nothing unless written to with `<-` syntax"]
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-pub struct BackPlace<'a, T: 'a> {
-    list: &'a mut LinkedList<T>,
-    node: IntermediateBox<Node<T>>,
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-impl<'a, T: 'a + fmt::Debug> fmt::Debug for BackPlace<'a, T> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.debug_tuple("BackPlace")
-         .field(&self.list)
-         .finish()
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> Placer<T> for BackPlace<'a, T> {
-    type Place = Self;
-
-    fn make_place(self) -> Self {
-        self
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-unsafe impl<'a, T> Place<T> for BackPlace<'a, T> {
-    fn pointer(&mut self) -> *mut T {
-        unsafe { &mut (*self.node.pointer()).element }
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> InPlace<T> for BackPlace<'a, T> {
-    type Owner = ();
-
-    unsafe fn finalize(self) {
-        let BackPlace { list, node } = self;
-        list.push_back_node(finalize(node));
-    }
-}
-
 // Ensure that `LinkedList` and its read-only iterators are covariant in their type parameters.
 #[allow(dead_code)]
 fn assert_covariance() {
diff --git a/src/liballoc/tests/binary_heap.rs b/src/liballoc/tests/binary_heap.rs
index 5c979d82e55..8494463463c 100644
--- a/src/liballoc/tests/binary_heap.rs
+++ b/src/liballoc/tests/binary_heap.rs
@@ -278,26 +278,6 @@ fn test_extend_specialization() {
     assert_eq!(a.into_sorted_vec(), [-20, -10, 1, 2, 3, 3, 5, 43]);
 }
 
-#[test]
-fn test_placement() {
-    let mut a = BinaryHeap::new();
-    &mut a <- 2;
-    &mut a <- 4;
-    &mut a <- 3;
-    assert_eq!(a.peek(), Some(&4));
-    assert_eq!(a.len(), 3);
-    &mut a <- 1;
-    assert_eq!(a.into_sorted_vec(), vec![1, 2, 3, 4]);
-}
-
-#[test]
-fn test_placement_panic() {
-    let mut heap = BinaryHeap::from(vec![1, 2, 3]);
-    fn mkpanic() -> usize { panic!() }
-    let _ = panic::catch_unwind(panic::AssertUnwindSafe(|| { &mut heap <- mkpanic(); }));
-    assert_eq!(heap.len(), 3);
-}
-
 #[allow(dead_code)]
 fn assert_covariance() {
     fn drain<'new>(d: Drain<'static, &'static str>) -> Drain<'new, &'new str> {
diff --git a/src/liballoc/tests/lib.rs b/src/liballoc/tests/lib.rs
index 0a7e9a8be94..1a49fb9964a 100644
--- a/src/liballoc/tests/lib.rs
+++ b/src/liballoc/tests/lib.rs
@@ -15,13 +15,11 @@
 #![feature(attr_literals)]
 #![feature(box_syntax)]
 #![cfg_attr(stage0, feature(inclusive_range_syntax))]
-#![feature(collection_placement)]
 #![feature(const_fn)]
 #![feature(drain_filter)]
 #![feature(exact_size_is_empty)]
 #![feature(iterator_step_by)]
 #![feature(pattern)]
-#![feature(placement_in_syntax)]
 #![feature(rand)]
 #![feature(slice_sort_by_cached_key)]
 #![feature(splice)]
diff --git a/src/liballoc/tests/vec.rs b/src/liballoc/tests/vec.rs
index 3c17a401bba..2895c53009d 100644
--- a/src/liballoc/tests/vec.rs
+++ b/src/liballoc/tests/vec.rs
@@ -10,7 +10,7 @@
 
 use std::borrow::Cow;
 use std::mem::size_of;
-use std::{usize, isize, panic};
+use std::{usize, isize};
 use std::vec::{Drain, IntoIter};
 use std::collections::CollectionAllocErr::*;
 
@@ -754,24 +754,6 @@ fn assert_covariance() {
 }
 
 #[test]
-fn test_placement() {
-    let mut vec = vec![1];
-    assert_eq!(vec.place_back() <- 2, &2);
-    assert_eq!(vec.len(), 2);
-    assert_eq!(vec.place_back() <- 3, &3);
-    assert_eq!(vec.len(), 3);
-    assert_eq!(&vec, &[1, 2, 3]);
-}
-
-#[test]
-fn test_placement_panic() {
-    let mut vec = vec![1, 2, 3];
-    fn mkpanic() -> usize { panic!() }
-    let _ = panic::catch_unwind(panic::AssertUnwindSafe(|| { vec.place_back() <- mkpanic(); }));
-    assert_eq!(vec.len(), 3);
-}
-
-#[test]
 fn from_into_inner() {
     let vec = vec![1, 2, 3];
     let ptr = vec.as_ptr();
diff --git a/src/liballoc/tests/vec_deque.rs b/src/liballoc/tests/vec_deque.rs
index fc1a0b624a5..75d3f01f8b6 100644
--- a/src/liballoc/tests/vec_deque.rs
+++ b/src/liballoc/tests/vec_deque.rs
@@ -1005,28 +1005,6 @@ fn test_is_empty() {
 }
 
 #[test]
-fn test_placement_in() {
-    let mut buf: VecDeque<isize> = VecDeque::new();
-    buf.place_back() <- 1;
-    buf.place_back() <- 2;
-    assert_eq!(buf, [1,2]);
-
-    buf.place_front() <- 3;
-    buf.place_front() <- 4;
-    assert_eq!(buf, [4,3,1,2]);
-
-    {
-        let ptr_head = buf.place_front() <- 5;
-        assert_eq!(*ptr_head, 5);
-    }
-    {
-        let ptr_tail = buf.place_back() <- 6;
-        assert_eq!(*ptr_tail, 6);
-    }
-    assert_eq!(buf, [5,4,3,1,2,6]);
-}
-
-#[test]
 fn test_reserve_exact_2() {
     // This is all the same as test_reserve
 
diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs
index 2eedb964f88..47c92028b14 100644
--- a/src/liballoc/vec.rs
+++ b/src/liballoc/vec.rs
@@ -76,7 +76,7 @@ use core::mem;
 #[cfg(not(test))]
 use core::num::Float;
 use core::ops::Bound::{Excluded, Included, Unbounded};
-use core::ops::{InPlace, Index, IndexMut, Place, Placer, RangeBounds};
+use core::ops::{Index, IndexMut, RangeBounds};
 use core::ops;
 use core::ptr;
 use core::ptr::NonNull;
@@ -1065,29 +1065,6 @@ impl<T> Vec<T> {
         }
     }
 
-    /// Returns a place for insertion at the back of the `Vec`.
-    ///
-    /// Using this method with placement syntax is equivalent to [`push`](#method.push),
-    /// but may be more efficient.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(collection_placement)]
-    /// #![feature(placement_in_syntax)]
-    ///
-    /// let mut vec = vec![1, 2];
-    /// vec.place_back() <- 3;
-    /// vec.place_back() <- 4;
-    /// assert_eq!(&vec, &[1, 2, 3, 4]);
-    /// ```
-    #[unstable(feature = "collection_placement",
-               reason = "placement protocol is subject to change",
-               issue = "30172")]
-    pub fn place_back(&mut self) -> PlaceBack<T> {
-        PlaceBack { vec: self }
-    }
-
     /// Removes the last element from a vector and returns it, or [`None`] if it
     /// is empty.
     ///
@@ -2492,57 +2469,6 @@ impl<'a, T> ExactSizeIterator for Drain<'a, T> {
 #[stable(feature = "fused", since = "1.26.0")]
 impl<'a, T> FusedIterator for Drain<'a, T> {}
 
-/// A place for insertion at the back of a `Vec`.
-///
-/// See [`Vec::place_back`](struct.Vec.html#method.place_back) for details.
-#[must_use = "places do nothing unless written to with `<-` syntax"]
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-#[derive(Debug)]
-pub struct PlaceBack<'a, T: 'a> {
-    vec: &'a mut Vec<T>,
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> Placer<T> for PlaceBack<'a, T> {
-    type Place = PlaceBack<'a, T>;
-
-    fn make_place(self) -> Self {
-        // This will panic or abort if we would allocate > isize::MAX bytes
-        // or if the length increment would overflow for zero-sized types.
-        if self.vec.len == self.vec.buf.cap() {
-            self.vec.buf.double();
-        }
-        self
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-unsafe impl<'a, T> Place<T> for PlaceBack<'a, T> {
-    fn pointer(&mut self) -> *mut T {
-        unsafe { self.vec.as_mut_ptr().offset(self.vec.len as isize) }
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> InPlace<T> for PlaceBack<'a, T> {
-    type Owner = &'a mut T;
-
-    unsafe fn finalize(mut self) -> &'a mut T {
-        let ptr = self.pointer();
-        self.vec.len += 1;
-        &mut *ptr
-    }
-}
-
-
 /// A splicing iterator for `Vec`.
 ///
 /// This struct is created by the [`splice()`] method on [`Vec`]. See its
diff --git a/src/liballoc/vec_deque.rs b/src/liballoc/vec_deque.rs
index 94d042a45aa..f28c8e38996 100644
--- a/src/liballoc/vec_deque.rs
+++ b/src/liballoc/vec_deque.rs
@@ -22,7 +22,7 @@ use core::fmt;
 use core::iter::{repeat, FromIterator, FusedIterator};
 use core::mem;
 use core::ops::Bound::{Excluded, Included, Unbounded};
-use core::ops::{Index, IndexMut, Place, Placer, InPlace, RangeBounds};
+use core::ops::{Index, IndexMut, RangeBounds};
 use core::ptr;
 use core::ptr::NonNull;
 use core::slice;
@@ -1885,56 +1885,6 @@ impl<T> VecDeque<T> {
             debug_assert!(!self.is_full());
         }
     }
-
-    /// Returns a place for insertion at the back of the `VecDeque`.
-    ///
-    /// Using this method with placement syntax is equivalent to [`push_back`](#method.push_back),
-    /// but may be more efficient.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(collection_placement)]
-    /// #![feature(placement_in_syntax)]
-    ///
-    /// use std::collections::VecDeque;
-    ///
-    /// let mut buf = VecDeque::new();
-    /// buf.place_back() <- 3;
-    /// buf.place_back() <- 4;
-    /// assert_eq!(&buf, &[3, 4]);
-    /// ```
-    #[unstable(feature = "collection_placement",
-               reason = "placement protocol is subject to change",
-               issue = "30172")]
-    pub fn place_back(&mut self) -> PlaceBack<T> {
-        PlaceBack { vec_deque: self }
-    }
-
-    /// Returns a place for insertion at the front of the `VecDeque`.
-    ///
-    /// Using this method with placement syntax is equivalent to [`push_front`](#method.push_front),
-    /// but may be more efficient.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// #![feature(collection_placement)]
-    /// #![feature(placement_in_syntax)]
-    ///
-    /// use std::collections::VecDeque;
-    ///
-    /// let mut buf = VecDeque::new();
-    /// buf.place_front() <- 3;
-    /// buf.place_front() <- 4;
-    /// assert_eq!(&buf, &[4, 3]);
-    /// ```
-    #[unstable(feature = "collection_placement",
-               reason = "placement protocol is subject to change",
-               issue = "30172")]
-    pub fn place_front(&mut self) -> PlaceFront<T> {
-        PlaceFront { vec_deque: self }
-    }
 }
 
 impl<T: Clone> VecDeque<T> {
@@ -2662,98 +2612,6 @@ impl<T> From<VecDeque<T>> for Vec<T> {
     }
 }
 
-/// A place for insertion at the back of a `VecDeque`.
-///
-/// See [`VecDeque::place_back`](struct.VecDeque.html#method.place_back) for details.
-#[must_use = "places do nothing unless written to with `<-` syntax"]
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-#[derive(Debug)]
-pub struct PlaceBack<'a, T: 'a> {
-    vec_deque: &'a mut VecDeque<T>,
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> Placer<T> for PlaceBack<'a, T> {
-    type Place = PlaceBack<'a, T>;
-
-    fn make_place(self) -> Self {
-        self.vec_deque.grow_if_necessary();
-        self
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-unsafe impl<'a, T> Place<T> for PlaceBack<'a, T> {
-    fn pointer(&mut self) -> *mut T {
-        unsafe { self.vec_deque.ptr().offset(self.vec_deque.head as isize) }
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> InPlace<T> for PlaceBack<'a, T> {
-    type Owner = &'a mut T;
-
-    unsafe fn finalize(self) -> &'a mut T {
-        let head = self.vec_deque.head;
-        self.vec_deque.head = self.vec_deque.wrap_add(head, 1);
-        &mut *(self.vec_deque.ptr().offset(head as isize))
-    }
-}
-
-/// A place for insertion at the front of a `VecDeque`.
-///
-/// See [`VecDeque::place_front`](struct.VecDeque.html#method.place_front) for details.
-#[must_use = "places do nothing unless written to with `<-` syntax"]
-#[unstable(feature = "collection_placement",
-           reason = "struct name and placement protocol are subject to change",
-           issue = "30172")]
-#[derive(Debug)]
-pub struct PlaceFront<'a, T: 'a> {
-    vec_deque: &'a mut VecDeque<T>,
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> Placer<T> for PlaceFront<'a, T> {
-    type Place = PlaceFront<'a, T>;
-
-    fn make_place(self) -> Self {
-        self.vec_deque.grow_if_necessary();
-        self
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-unsafe impl<'a, T> Place<T> for PlaceFront<'a, T> {
-    fn pointer(&mut self) -> *mut T {
-        let tail = self.vec_deque.wrap_sub(self.vec_deque.tail, 1);
-        unsafe { self.vec_deque.ptr().offset(tail as isize) }
-    }
-}
-
-#[unstable(feature = "collection_placement",
-           reason = "placement protocol is subject to change",
-           issue = "30172")]
-impl<'a, T> InPlace<T> for PlaceFront<'a, T> {
-    type Owner = &'a mut T;
-
-    unsafe fn finalize(self) -> &'a mut T {
-        self.vec_deque.tail = self.vec_deque.wrap_sub(self.vec_deque.tail, 1);
-        &mut *(self.vec_deque.ptr().offset(self.vec_deque.tail as isize))
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use test;
generated by cgit-pink 1.4.1-3-g733a5 (git 2.37.1) at 2026-03-18 13:36:42 +0000