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 </pre><pre class="rust"><code><span class="doccomment">//! This module defines an `IdleNotifiedSet`, which is a collection of elements.
 //! Each element is intended to correspond to a task, and the collection will
 //! keep track of which tasks have had their waker notified, and which have not.
 //!
 //! Each entry in the set holds some user-specified value. The value&#39;s type is
 //! specified using the `T` parameter. It will usually be a `JoinHandle` or
 //! similar.

 </span><span class="kw">use </span>std::marker::PhantomPinned;
 <span class="kw">use </span>std::mem::ManuallyDrop;
 <span class="kw">use </span>std::ptr::NonNull;
 <span class="kw">use </span>std::task::{Context, Waker};

 <span class="kw">use </span><span class="kw">crate</span>::loom::cell::UnsafeCell;
 <span class="kw">use </span><span class="kw">crate</span>::loom::sync::{Arc, Mutex};
 <span class="kw">use </span><span class="kw">crate</span>::util::linked_list::{<span class="self">self</span>, Link};
 <span class="kw">use </span><span class="kw">crate</span>::util::{waker_ref, Wake};

 <span class="kw">type </span>LinkedList&lt;T&gt; =
     linked_list::LinkedList&lt;ListEntry&lt;T&gt;, &lt;ListEntry&lt;T&gt; <span class="kw">as </span>linked_list::Link&gt;::Target&gt;;

 <span class="doccomment">/// This is the main handle to the collection.
 </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>IdleNotifiedSet&lt;T&gt; {
     lists: Arc&lt;Lists&lt;T&gt;&gt;,
     length: usize,
 }

 <span class="doccomment">/// A handle to an entry that is guaranteed to be stored in the idle or notified
 /// list of its `IdleNotifiedSet`. This value borrows the `IdleNotifiedSet`
 /// mutably to prevent the entry from being moved to the `Neither` list, which
 /// only the `IdleNotifiedSet` may do.
 ///
 /// The main consequence of being stored in one of the lists is that the `value`
 /// field has not yet been consumed.
 ///
 /// Note: This entry can be moved from the idle to the notified list while this
 /// object exists by waking its waker.
 </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>EntryInOneOfTheLists&lt;<span class="lifetime">&#39;a</span>, T&gt; {
     entry: Arc&lt;ListEntry&lt;T&gt;&gt;,
     set: <span class="kw-2">&amp;</span><span class="lifetime">&#39;a </span><span class="kw-2">mut </span>IdleNotifiedSet&lt;T&gt;,
 }

 <span class="kw">type </span>Lists&lt;T&gt; = Mutex&lt;ListsInner&lt;T&gt;&gt;;

 <span class="doccomment">/// The linked lists hold strong references to the ListEntry items, and the
 /// ListEntry items also hold a strong reference back to the Lists object, but
 /// the destructor of the `IdleNotifiedSet` will clear the two lists, so once
 /// that object is destroyed, no ref-cycles will remain.
 </span><span class="kw">struct </span>ListsInner&lt;T&gt; {
     notified: LinkedList&lt;T&gt;,
     idle: LinkedList&lt;T&gt;,
     <span class="doccomment">/// Whenever an element in the `notified` list is woken, this waker will be
     /// notified and consumed, if it exists.
     </span>waker: <span class="prelude-ty">Option</span>&lt;Waker&gt;,
 }

 <span class="doccomment">/// Which of the two lists in the shared Lists object is this entry stored in?
 ///
 /// If the value is `Idle`, then an entry&#39;s waker may move it to the notified
 /// list. Otherwise, only the `IdleNotifiedSet` may move it.
 ///
 /// If the value is `Neither`, then it is still possible that the entry is in
 /// some third external list (this happens in `drain`).
 </span><span class="attribute">#[derive(Copy, Clone, Eq, PartialEq)]
 </span><span class="kw">enum </span>List {
     Notified,
     Idle,
     Neither,
 }

 <span class="doccomment">/// An entry in the list.
 ///
 /// # Safety
 ///
 /// The `my_list` field must only be accessed while holding the mutex in
 /// `parent`. It is an invariant that the value of `my_list` corresponds to
 /// which linked list in the `parent` holds this entry. Once this field takes
 /// the value `Neither`, then it may never be modified again.
 ///
 /// If the value of `my_list` is `Notified` or `Idle`, then the `pointers` field
 /// must only be accessed while holding the mutex. If the value of `my_list` is
 /// `Neither`, then the `pointers` field may be accessed by the
 /// `IdleNotifiedSet` (this happens inside `drain`).
 ///
 /// The `value` field is owned by the `IdleNotifiedSet` and may only be accessed
 /// by the `IdleNotifiedSet`. The operation that sets the value of `my_list` to
 /// `Neither` assumes ownership of the `value`, and it must either drop it or
 /// move it out from this entry to prevent it from getting leaked. (Since the
 /// two linked lists are emptied in the destructor of `IdleNotifiedSet`, the
 /// value should not be leaked.)
 </span><span class="kw">struct </span>ListEntry&lt;T&gt; {
     <span class="doccomment">/// The linked list pointers of the list this entry is in.
     </span>pointers: linked_list::Pointers&lt;ListEntry&lt;T&gt;&gt;,
     <span class="doccomment">/// Pointer to the shared `Lists` struct.
     </span>parent: Arc&lt;Lists&lt;T&gt;&gt;,
     <span class="doccomment">/// The value stored in this entry.
     </span>value: UnsafeCell&lt;ManuallyDrop&lt;T&gt;&gt;,
     <span class="doccomment">/// Used to remember which list this entry is in.
     </span>my_list: UnsafeCell&lt;List&gt;,
     <span class="doccomment">/// Required by the `linked_list::Pointers` field.
     </span>_pin: PhantomPinned,
 }

 <span class="macro">generate_addr_of_methods! </span>{
     <span class="kw">impl</span>&lt;T&gt; ListEntry&lt;T&gt; {
         <span class="kw">unsafe fn </span>addr_of_pointers(<span class="self">self</span>: NonNull&lt;<span class="self">Self</span>&gt;) -&gt; NonNull&lt;linked_list::Pointers&lt;ListEntry&lt;T&gt;&gt;&gt; {
             <span class="kw-2">&amp;</span><span class="self">self</span>.pointers
         }
     }
 }

 <span class="comment">// With mutable access to the `IdleNotifiedSet`, you can get mutable access to
 // the values.
 </span><span class="kw">unsafe impl</span>&lt;T: Send&gt; Send <span class="kw">for </span>IdleNotifiedSet&lt;T&gt; {}
 <span class="comment">// With the current API we strictly speaking don&#39;t even need `T: Sync`, but we
 // require it anyway to support adding &amp;self APIs that access the values in the
 // future.
 </span><span class="kw">unsafe impl</span>&lt;T: Sync&gt; Sync <span class="kw">for </span>IdleNotifiedSet&lt;T&gt; {}

 <span class="comment">// These impls control when it is safe to create a Waker. Since the waker does
 // not allow access to the value in any way (including its destructor), it is
 // not necessary for `T` to be Send or Sync.
 </span><span class="kw">unsafe impl</span>&lt;T&gt; Send <span class="kw">for </span>ListEntry&lt;T&gt; {}
 <span class="kw">unsafe impl</span>&lt;T&gt; Sync <span class="kw">for </span>ListEntry&lt;T&gt; {}

 <span class="kw">impl</span>&lt;T&gt; IdleNotifiedSet&lt;T&gt; {
     <span class="doccomment">/// Create a new IdleNotifiedSet.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new() -&gt; <span class="self">Self </span>{
         <span class="kw">let </span>lists = Mutex::new(ListsInner {
             notified: LinkedList::new(),
             idle: LinkedList::new(),
             waker: <span class="prelude-val">None</span>,
         });

         IdleNotifiedSet {
             lists: Arc::new(lists),
             length: <span class="number">0</span>,
         }
     }

     <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>len(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; usize {
         <span class="self">self</span>.length
     }

     <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>is_empty(<span class="kw-2">&amp;</span><span class="self">self</span>) -&gt; bool {
         <span class="self">self</span>.length == <span class="number">0
     </span>}

     <span class="doccomment">/// Insert the given value into the `idle` list.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>insert_idle(<span class="kw-2">&amp;mut </span><span class="self">self</span>, value: T) -&gt; EntryInOneOfTheLists&lt;<span class="lifetime">&#39;_</span>, T&gt; {
         <span class="self">self</span>.length += <span class="number">1</span>;

         <span class="kw">let </span>entry = Arc::new(ListEntry {
             parent: <span class="self">self</span>.lists.clone(),
             value: UnsafeCell::new(ManuallyDrop::new(value)),
             my_list: UnsafeCell::new(List::Idle),
             pointers: linked_list::Pointers::new(),
             _pin: PhantomPinned,
         });

         {
             <span class="kw">let </span><span class="kw-2">mut </span>lock = <span class="self">self</span>.lists.lock();
             lock.idle.push_front(entry.clone());
         }

         <span class="comment">// Safety: We just put the entry in the idle list, so it is in one of the lists.
         </span>EntryInOneOfTheLists { entry, set: <span class="self">self </span>}
     }

     <span class="doccomment">/// Pop an entry from the notified list to poll it. The entry is moved to
     /// the idle list atomically.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>pop_notified(<span class="kw-2">&amp;mut </span><span class="self">self</span>, waker: <span class="kw-2">&amp;</span>Waker) -&gt; <span class="prelude-ty">Option</span>&lt;EntryInOneOfTheLists&lt;<span class="lifetime">&#39;_</span>, T&gt;&gt; {
         <span class="comment">// We don&#39;t decrement the length because this call moves the entry to
         // the idle list rather than removing it.
         </span><span class="kw">if </span><span class="self">self</span>.length == <span class="number">0 </span>{
             <span class="comment">// Fast path.
             </span><span class="kw">return </span><span class="prelude-val">None</span>;
         }

         <span class="kw">let </span><span class="kw-2">mut </span>lock = <span class="self">self</span>.lists.lock();

         <span class="kw">let </span>should_update_waker = <span class="kw">match </span>lock.waker.as_mut() {
             <span class="prelude-val">Some</span>(cur_waker) =&gt; !waker.will_wake(cur_waker),
             <span class="prelude-val">None </span>=&gt; <span class="bool-val">true</span>,
         };
         <span class="kw">if </span>should_update_waker {
             lock.waker = <span class="prelude-val">Some</span>(waker.clone());
         }

         <span class="comment">// Pop the entry, returning None if empty.
         </span><span class="kw">let </span>entry = lock.notified.pop_back()<span class="question-mark">?</span>;

         lock.idle.push_front(entry.clone());

         <span class="comment">// Safety: We are holding the lock.
         </span>entry.my_list.with_mut(|ptr| <span class="kw">unsafe </span>{
             <span class="kw-2">*</span>ptr = List::Idle;
         });

         drop(lock);

         <span class="comment">// Safety: We just put the entry in the idle list, so it is in one of the lists.
         </span><span class="prelude-val">Some</span>(EntryInOneOfTheLists { entry, set: <span class="self">self </span>})
     }

     <span class="doccomment">/// Call a function on every element in this list.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>for_each&lt;F: FnMut(<span class="kw-2">&amp;mut </span>T)&gt;(<span class="kw-2">&amp;mut </span><span class="self">self</span>, <span class="kw-2">mut </span>func: F) {
         <span class="kw">fn </span>get_ptrs&lt;T&gt;(list: <span class="kw-2">&amp;mut </span>LinkedList&lt;T&gt;, ptrs: <span class="kw-2">&amp;mut </span>Vec&lt;<span class="kw-2">*mut </span>T&gt;) {
             <span class="kw">let </span><span class="kw-2">mut </span>node = list.last();

             <span class="kw">while let </span><span class="prelude-val">Some</span>(entry) = node {
                 ptrs.push(entry.value.with_mut(|ptr| {
                     <span class="kw">let </span>ptr: <span class="kw-2">*mut </span>ManuallyDrop&lt;T&gt; = ptr;
                     <span class="kw">let </span>ptr: <span class="kw-2">*mut </span>T = ptr.cast();
                     ptr
                 }));

                 <span class="kw">let </span>prev = entry.pointers.get_prev();
                 node = prev.map(|prev| <span class="kw">unsafe </span>{ <span class="kw-2">&amp;*</span>prev.as_ptr() });
             }
         }

         <span class="comment">// Atomically get a raw pointer to the value of every entry.
         //
         // Since this only locks the mutex once, it is not possible for a value
         // to get moved from the idle list to the notified list during the
         // operation, which would otherwise result in some value being listed
         // twice.
         </span><span class="kw">let </span><span class="kw-2">mut </span>ptrs = Vec::with_capacity(<span class="self">self</span>.len());
         {
             <span class="kw">let </span><span class="kw-2">mut </span>lock = <span class="self">self</span>.lists.lock();

             get_ptrs(<span class="kw-2">&amp;mut </span>lock.idle, <span class="kw-2">&amp;mut </span>ptrs);
             get_ptrs(<span class="kw-2">&amp;mut </span>lock.notified, <span class="kw-2">&amp;mut </span>ptrs);
         }
         <span class="macro">debug_assert_eq!</span>(ptrs.len(), ptrs.capacity());

         <span class="kw">for </span>ptr <span class="kw">in </span>ptrs {
             <span class="comment">// Safety: When we grabbed the pointers, the entries were in one of
             // the two lists. This means that their value was valid at the time,
             // and it must still be valid because we are the IdleNotifiedSet,
             // and only we can remove an entry from the two lists. (It&#39;s
             // possible that an entry is moved from one list to the other during
             // this loop, but that is ok.)
             </span>func(<span class="kw">unsafe </span>{ <span class="kw-2">&amp;mut *</span>ptr });
         }
     }

     <span class="doccomment">/// Remove all entries in both lists, applying some function to each element.
     ///
     /// The closure is called on all elements even if it panics. Having it panic
     /// twice is a double-panic, and will abort the application.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>drain&lt;F: FnMut(T)&gt;(<span class="kw-2">&amp;mut </span><span class="self">self</span>, func: F) {
         <span class="kw">if </span><span class="self">self</span>.length == <span class="number">0 </span>{
             <span class="comment">// Fast path.
             </span><span class="kw">return</span>;
         }
         <span class="self">self</span>.length = <span class="number">0</span>;

         <span class="comment">// The LinkedList is not cleared on panic, so we use a bomb to clear it.
         //
         // This value has the invariant that any entry in its `all_entries` list
         // has `my_list` set to `Neither` and that the value has not yet been
         // dropped.
         </span><span class="kw">struct </span>AllEntries&lt;T, F: FnMut(T)&gt; {
             all_entries: LinkedList&lt;T&gt;,
             func: F,
         }

         <span class="kw">impl</span>&lt;T, F: FnMut(T)&gt; AllEntries&lt;T, F&gt; {
             <span class="kw">fn </span>pop_next(<span class="kw-2">&amp;mut </span><span class="self">self</span>) -&gt; bool {
                 <span class="kw">if let </span><span class="prelude-val">Some</span>(entry) = <span class="self">self</span>.all_entries.pop_back() {
                     <span class="comment">// Safety: We just took this value from the list, so we can
                     // destroy the value in the entry.
                     </span>entry
                         .value
                         .with_mut(|ptr| <span class="kw">unsafe </span>{ (<span class="self">self</span>.func)(ManuallyDrop::take(<span class="kw-2">&amp;mut *</span>ptr)) });
                     <span class="bool-val">true
                 </span>} <span class="kw">else </span>{
                     <span class="bool-val">false
                 </span>}
             }
         }

         <span class="kw">impl</span>&lt;T, F: FnMut(T)&gt; Drop <span class="kw">for </span>AllEntries&lt;T, F&gt; {
             <span class="kw">fn </span>drop(<span class="kw-2">&amp;mut </span><span class="self">self</span>) {
                 <span class="kw">while </span><span class="self">self</span>.pop_next() {}
             }
         }

         <span class="kw">let </span><span class="kw-2">mut </span>all_entries = AllEntries {
             all_entries: LinkedList::new(),
             func,
         };

         <span class="comment">// Atomically move all entries to the new linked list in the AllEntries
         // object.
         </span>{
             <span class="kw">let </span><span class="kw-2">mut </span>lock = <span class="self">self</span>.lists.lock();
             <span class="kw">unsafe </span>{
                 <span class="comment">// Safety: We are holding the lock and `all_entries` is a new
                 // LinkedList.
                 </span>move_to_new_list(<span class="kw-2">&amp;mut </span>lock.idle, <span class="kw-2">&amp;mut </span>all_entries.all_entries);
                 move_to_new_list(<span class="kw-2">&amp;mut </span>lock.notified, <span class="kw-2">&amp;mut </span>all_entries.all_entries);
             }
         }

         <span class="comment">// Keep destroying entries in the list until it is empty.
         //
         // If the closure panics, then the destructor of the `AllEntries` bomb
         // ensures that we keep running the destructor on the remaining values.
         // A second panic will abort the program.
         </span><span class="kw">while </span>all_entries.pop_next() {}
     }
 }

 <span class="doccomment">/// # Safety
 ///
 /// The mutex for the entries must be held, and the target list must be such
 /// that setting `my_list` to `Neither` is ok.
 </span><span class="kw">unsafe fn </span>move_to_new_list&lt;T&gt;(from: <span class="kw-2">&amp;mut </span>LinkedList&lt;T&gt;, to: <span class="kw-2">&amp;mut </span>LinkedList&lt;T&gt;) {
     <span class="kw">while let </span><span class="prelude-val">Some</span>(entry) = from.pop_back() {
         entry.my_list.with_mut(|ptr| {
             <span class="kw-2">*</span>ptr = List::Neither;
         });
         to.push_front(entry);
     }
 }

 <span class="kw">impl</span>&lt;<span class="lifetime">&#39;a</span>, T&gt; EntryInOneOfTheLists&lt;<span class="lifetime">&#39;a</span>, T&gt; {
     <span class="doccomment">/// Remove this entry from the list it is in, returning the value associated
     /// with the entry.
     ///
     /// This consumes the value, since it is no longer guaranteed to be in a
     /// list.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>remove(<span class="self">self</span>) -&gt; T {
         <span class="self">self</span>.set.length -= <span class="number">1</span>;

         {
             <span class="kw">let </span><span class="kw-2">mut </span>lock = <span class="self">self</span>.set.lists.lock();

             <span class="comment">// Safety: We are holding the lock so there is no race, and we will
             // remove the entry afterwards to uphold invariants.
             </span><span class="kw">let </span>old_my_list = <span class="self">self</span>.entry.my_list.with_mut(|ptr| <span class="kw">unsafe </span>{
                 <span class="kw">let </span>old_my_list = <span class="kw-2">*</span>ptr;
                 <span class="kw-2">*</span>ptr = List::Neither;
                 old_my_list
             });

             <span class="kw">let </span>list = <span class="kw">match </span>old_my_list {
                 List::Idle =&gt; <span class="kw-2">&amp;mut </span>lock.idle,
                 List::Notified =&gt; <span class="kw-2">&amp;mut </span>lock.notified,
                 <span class="comment">// An entry in one of the lists is in one of the lists.
                 </span>List::Neither =&gt; <span class="macro">unreachable!</span>(),
             };

             <span class="kw">unsafe </span>{
                 <span class="comment">// Safety: We just checked that the entry is in this particular
                 // list.
                 </span>list.remove(ListEntry::as_raw(<span class="kw-2">&amp;</span><span class="self">self</span>.entry)).unwrap();
             }
         }

         <span class="comment">// By setting `my_list` to `Neither`, we have taken ownership of the
         // value. We return it to the caller.
         //
         // Safety: We have a mutable reference to the `IdleNotifiedSet` that
         // owns this entry, so we can use its permission to access the value.
         </span><span class="self">self</span>.entry
             .value
             .with_mut(|ptr| <span class="kw">unsafe </span>{ ManuallyDrop::take(<span class="kw-2">&amp;mut *</span>ptr) })
     }

     <span class="doccomment">/// Access the value in this entry together with a context for its waker.
     </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>with_value_and_context&lt;F, U&gt;(<span class="kw-2">&amp;mut </span><span class="self">self</span>, func: F) -&gt; U
     <span class="kw">where
         </span>F: FnOnce(<span class="kw-2">&amp;mut </span>T, <span class="kw-2">&amp;mut </span>Context&lt;<span class="lifetime">&#39;_</span>&gt;) -&gt; U,
         T: <span class="lifetime">&#39;static</span>,
     {
         <span class="kw">let </span>waker = waker_ref(<span class="kw-2">&amp;</span><span class="self">self</span>.entry);

         <span class="kw">let </span><span class="kw-2">mut </span>context = Context::from_waker(<span class="kw-2">&amp;</span>waker);

         <span class="comment">// Safety: We have a mutable reference to the `IdleNotifiedSet` that
         // owns this entry, so we can use its permission to access the value.
         </span><span class="self">self</span>.entry
             .value
             .with_mut(|ptr| <span class="kw">unsafe </span>{ func(<span class="kw-2">&amp;mut *</span>ptr, <span class="kw-2">&amp;mut </span>context) })
     }
 }

 <span class="kw">impl</span>&lt;T&gt; Drop <span class="kw">for </span>IdleNotifiedSet&lt;T&gt; {
     <span class="kw">fn </span>drop(<span class="kw-2">&amp;mut </span><span class="self">self</span>) {
         <span class="comment">// Clear both lists.
         </span><span class="self">self</span>.drain(drop);

         <span class="attribute">#[cfg(debug_assertions)]
         </span><span class="kw">if </span>!std::thread::panicking() {
             <span class="kw">let </span>lock = <span class="self">self</span>.lists.lock();
             <span class="macro">assert!</span>(lock.idle.is_empty());
             <span class="macro">assert!</span>(lock.notified.is_empty());
         }
     }
 }

 <span class="kw">impl</span>&lt;T: <span class="lifetime">&#39;static</span>&gt; Wake <span class="kw">for </span>ListEntry&lt;T&gt; {
     <span class="kw">fn </span>wake_by_ref(me: <span class="kw-2">&amp;</span>Arc&lt;<span class="self">Self</span>&gt;) {
         <span class="kw">let </span><span class="kw-2">mut </span>lock = me.parent.lock();

         <span class="comment">// Safety: We are holding the lock and we will update the lists to
         // maintain invariants.
         </span><span class="kw">let </span>old_my_list = me.my_list.with_mut(|ptr| <span class="kw">unsafe </span>{
             <span class="kw">let </span>old_my_list = <span class="kw-2">*</span>ptr;
             <span class="kw">if </span>old_my_list == List::Idle {
                 <span class="kw-2">*</span>ptr = List::Notified;
             }
             old_my_list
         });

         <span class="kw">if </span>old_my_list == List::Idle {
             <span class="comment">// We move ourself to the notified list.
             </span><span class="kw">let </span>me = <span class="kw">unsafe </span>{
                 <span class="comment">// Safety: We just checked that we are in this particular list.
                 </span>lock.idle.remove(NonNull::from(<span class="kw-2">&amp;**</span>me)).unwrap()
             };
             lock.notified.push_front(me);

             <span class="kw">if let </span><span class="prelude-val">Some</span>(waker) = lock.waker.take() {
                 drop(lock);
                 waker.wake();
             }
         }
     }

     <span class="kw">fn </span>wake(me: Arc&lt;<span class="self">Self</span>&gt;) {
         <span class="self">Self</span>::wake_by_ref(<span class="kw-2">&amp;</span>me)
     }
 }

 <span class="doccomment">/// # Safety
 ///
 /// `ListEntry` is forced to be !Unpin.
 </span><span class="kw">unsafe impl</span>&lt;T&gt; linked_list::Link <span class="kw">for </span>ListEntry&lt;T&gt; {
     <span class="kw">type </span>Handle = Arc&lt;ListEntry&lt;T&gt;&gt;;
     <span class="kw">type </span>Target = ListEntry&lt;T&gt;;

     <span class="kw">fn </span>as_raw(handle: <span class="kw-2">&amp;</span><span class="self">Self</span>::Handle) -&gt; NonNull&lt;ListEntry&lt;T&gt;&gt; {
         <span class="kw">let </span>ptr: <span class="kw-2">*const </span>ListEntry&lt;T&gt; = Arc::as_ptr(handle);
         <span class="comment">// Safety: We can&#39;t get a null pointer from `Arc::as_ptr`.
         </span><span class="kw">unsafe </span>{ NonNull::new_unchecked(ptr <span class="kw">as </span><span class="kw-2">*mut </span>ListEntry&lt;T&gt;) }
     }

     <span class="kw">unsafe fn </span>from_raw(ptr: NonNull&lt;ListEntry&lt;T&gt;&gt;) -&gt; Arc&lt;ListEntry&lt;T&gt;&gt; {
         Arc::from_raw(ptr.as_ptr())
     }

     <span class="kw">unsafe fn </span>pointers(
         target: NonNull&lt;ListEntry&lt;T&gt;&gt;,
     ) -&gt; NonNull&lt;linked_list::Pointers&lt;ListEntry&lt;T&gt;&gt;&gt; {
         ListEntry::addr_of_pointers(target)
     }
 }
 </code></pre></div>
 </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="tokio" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html>