Auto merge of #41773 - frewsxcv:rollup, r=frewsxcv

Rollup of 9 pull requests

- Successful merges: #41064, #41307, #41512, #41582, #41678, #41722, #41734, #41761, #41763
- Failed merges:

src/doc/nomicon

@@ -1 +1 @@
-Subproject commit 616b98444ff4eb5260deee95ee3e090dfd98b947
+Subproject commit 6fa139b1630a9bb95dcd60cfc90aff9c19e54580

src/liballoc/arc.rs

@@ -277,8 +277,7 @@ impl<T> Arc<T> {
         atomic::fence(Acquire);
 
         unsafe {
-            let ptr = *this.ptr;
+            let elem = ptr::read(&this.ptr.as_ref().data);
-            let elem = ptr::read(&(*ptr).data);
 
             // Make a weak pointer to clean up the implicit strong-weak reference
             let _weak = Weak { ptr: this.ptr };
@@ -306,7 +305,7 @@ impl<T> Arc<T> {
     /// ```
     #[stable(feature = "rc_raw", since = "1.17.0")]
     pub fn into_raw(this: Self) -> *const T {
-        let ptr = unsafe { &(**this.ptr).data as *const _ };
+        let ptr: *const T = &*this;
         mem::forget(this);
         ptr
     }
@@ -345,7 +344,7 @@ impl<T> Arc<T> {
         // `data` field from the pointer.
         let ptr = (ptr as *const u8).offset(-offset_of!(ArcInner<T>, data));
         Arc {
-            ptr: Shared::new(ptr as *const _),
+            ptr: Shared::new(ptr as *mut u8 as *mut _),
         }
     }
 }
@@ -452,17 +451,17 @@ impl<T: ?Sized> Arc<T> {
         // `ArcInner` structure itself is `Sync` because the inner data is
         // `Sync` as well, so we're ok loaning out an immutable pointer to these
         // contents.
-        unsafe { &**self.ptr }
+        unsafe { self.ptr.as_ref() }
     }
 
     // Non-inlined part of `drop`.
     #[inline(never)]
     unsafe fn drop_slow(&mut self) {
-        let ptr = self.ptr.as_mut_ptr();
+        let ptr = self.ptr.as_ptr();
 
         // Destroy the data at this time, even though we may not free the box
         // allocation itself (there may still be weak pointers lying around).
-        ptr::drop_in_place(&mut (*ptr).data);
+        ptr::drop_in_place(&mut self.ptr.as_mut().data);
 
         if self.inner().weak.fetch_sub(1, Release) == 1 {
             atomic::fence(Acquire);
@@ -488,9 +487,7 @@ impl<T: ?Sized> Arc<T> {
     /// assert!(!Arc::ptr_eq(&five, &other_five));
     /// ```
     pub fn ptr_eq(this: &Self, other: &Self) -> bool {
-        let this_ptr: *const ArcInner<T> = *this.ptr;
+        this.ptr.as_ptr() == other.ptr.as_ptr()
-        let other_ptr: *const ArcInner<T> = *other.ptr;
-        this_ptr == other_ptr
     }
 }
 
@@ -621,7 +618,7 @@ impl<T: Clone> Arc<T> {
                 // here (due to zeroing) because data is no longer accessed by
                 // other threads (due to there being no more strong refs at this
                 // point).
-                let mut swap = Arc::new(ptr::read(&(**weak.ptr).data));
+                let mut swap = Arc::new(ptr::read(&weak.ptr.as_ref().data));
                 mem::swap(this, &mut swap);
                 mem::forget(swap);
             }
@@ -634,8 +631,7 @@ impl<T: Clone> Arc<T> {
         // As with `get_mut()`, the unsafety is ok because our reference was
         // either unique to begin with, or became one upon cloning the contents.
         unsafe {
-            let inner = &mut *this.ptr.as_mut_ptr();
+            &mut this.ptr.as_mut().data
-            &mut inner.data
         }
     }
 }
@@ -677,8 +673,7 @@ impl<T: ?Sized> Arc<T> {
             // the Arc itself to be `mut`, so we're returning the only possible
             // reference to the inner data.
             unsafe {
-                let inner = &mut *this.ptr.as_mut_ptr();
+                Some(&mut this.ptr.as_mut().data)
-                Some(&mut inner.data)
             }
         } else {
             None
@@ -878,7 +873,7 @@ impl<T: ?Sized> Weak<T> {
     #[inline]
     fn inner(&self) -> &ArcInner<T> {
         // See comments above for why this is "safe"
-        unsafe { &**self.ptr }
+        unsafe { self.ptr.as_ref() }
     }
 }
 
@@ -962,7 +957,7 @@ impl<T: ?Sized> Drop for Weak<T> {
     /// assert!(other_weak_foo.upgrade().is_none());
     /// ```
     fn drop(&mut self) {
-        let ptr = *self.ptr;
+        let ptr = self.ptr.as_ptr();
 
         // If we find out that we were the last weak pointer, then its time to
         // deallocate the data entirely. See the discussion in Arc::drop() about
@@ -1143,7 +1138,7 @@ impl<T: ?Sized + fmt::Debug> fmt::Debug for Arc<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: ?Sized> fmt::Pointer for Arc<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        fmt::Pointer::fmt(&*self.ptr, f)
+        fmt::Pointer::fmt(&self.ptr, f)
     }
 }
 

src/liballoc/boxed.rs

@@ -156,7 +156,7 @@ fn make_place<T>() -> IntermediateBox<T> {
     let align = mem::align_of::<T>();
 
     let p = if size == 0 {
-        heap::EMPTY as *mut u8
+        mem::align_of::<T>() as *mut u8
     } else {
         let p = unsafe { heap::allocate(size, align) };
         if p.is_null() {

src/liballoc/heap.rs

@@ -138,7 +138,9 @@ pub fn usable_size(size: usize, align: usize) -> usize {
 ///
 /// This preserves the non-null invariant for types like `Box<T>`. The address
 /// may overlap with non-zero-size memory allocations.
-pub const EMPTY: *mut () = 0x1 as *mut ();
+#[rustc_deprecated(since = "1.19", reason = "Use Unique/Shared::empty() instead")]
+#[unstable(feature = "heap_api", issue = "27700")]
+pub const EMPTY: *mut () = 1 as *mut ();
 
 /// The allocator for unique pointers.
 // This function must not unwind. If it does, MIR trans will fail.
@@ -147,7 +149,7 @@ pub const EMPTY: *mut () = 0x1 as *mut ();
 #[inline]
 unsafe fn exchange_malloc(size: usize, align: usize) -> *mut u8 {
     if size == 0 {
-        EMPTY as *mut u8
+        align as *mut u8
     } else {
         let ptr = allocate(size, align);
         if ptr.is_null() {

src/liballoc/raw_vec.rs

@@ -22,13 +22,13 @@ use core::cmp;
 /// involved. This type is excellent for building your own data structures like Vec and VecDeque.
 /// In particular:
 ///
-/// * Produces heap::EMPTY on zero-sized types
+/// * Produces Unique::empty() on zero-sized types
-/// * Produces heap::EMPTY on zero-length allocations
+/// * Produces Unique::empty() on zero-length allocations
 /// * Catches all overflows in capacity computations (promotes them to "capacity overflow" panics)
 /// * Guards against 32-bit systems allocating more than isize::MAX bytes
 /// * Guards against overflowing your length
 /// * Aborts on OOM
-/// * Avoids freeing heap::EMPTY
+/// * Avoids freeing Unique::empty()
 /// * Contains a ptr::Unique and thus endows the user with all related benefits
 ///
 /// This type does not in anyway inspect the memory that it manages. When dropped it *will*
@@ -55,15 +55,13 @@ impl<T> RawVec<T> {
     /// it makes a RawVec with capacity `usize::MAX`. Useful for implementing
     /// delayed allocation.
     pub fn new() -> Self {
-        unsafe {
+        // !0 is usize::MAX. This branch should be stripped at compile time.
-            // !0 is usize::MAX. This branch should be stripped at compile time.
+        let cap = if mem::size_of::<T>() == 0 { !0 } else { 0 };
-            let cap = if mem::size_of::<T>() == 0 { !0 } else { 0 };
 
-            // heap::EMPTY doubles as "unallocated" and "zero-sized allocation"
+        // Unique::empty() doubles as "unallocated" and "zero-sized allocation"
-            RawVec {
+        RawVec {
-                ptr: Unique::new(heap::EMPTY as *mut T),
+            ptr: Unique::empty(),
-                cap: cap,
+            cap: cap,
-            }
         }
     }
 
@@ -101,7 +99,7 @@ impl<T> RawVec<T> {
 
             // handles ZSTs and `cap = 0` alike
             let ptr = if alloc_size == 0 {
-                heap::EMPTY as *mut u8
+                mem::align_of::<T>() as *mut u8
             } else {
                 let align = mem::align_of::<T>();
                 let ptr = if zeroed {
@@ -148,10 +146,10 @@ impl<T> RawVec<T> {
 
 impl<T> RawVec<T> {
     /// Gets a raw pointer to the start of the allocation. Note that this is
-    /// heap::EMPTY if `cap = 0` or T is zero-sized. In the former case, you must
+    /// Unique::empty() if `cap = 0` or T is zero-sized. In the former case, you must
     /// be careful.
     pub fn ptr(&self) -> *mut T {
-        *self.ptr
+        self.ptr.as_ptr()
     }
 
     /// Gets the capacity of the allocation.
@@ -563,7 +561,7 @@ unsafe impl<#[may_dangle] T> Drop for RawVec<T> {
 
             let num_bytes = elem_size * self.cap;
             unsafe {
-                heap::deallocate(*self.ptr as *mut _, num_bytes, align);
+                heap::deallocate(self.ptr() as *mut u8, num_bytes, align);
             }
         }
     }

src/liballoc/rc.rs

@@ -230,7 +230,7 @@ use core::cell::Cell;
 use core::cmp::Ordering;
 use core::fmt;
 use core::hash::{Hash, Hasher};
-use core::intrinsics::{abort, assume};
+use core::intrinsics::abort;
 use core::marker;
 use core::marker::Unsize;
 use core::mem::{self, align_of_val, forget, size_of, size_of_val, uninitialized};
@@ -358,7 +358,7 @@ impl<T> Rc<T> {
     /// ```
     #[stable(feature = "rc_raw", since = "1.17.0")]
     pub fn into_raw(this: Self) -> *const T {
-        let ptr = unsafe { &mut (*this.ptr.as_mut_ptr()).value as *const _ };
+        let ptr: *const T = &*this;
         mem::forget(this);
         ptr
     }
@@ -395,7 +395,11 @@ impl<T> Rc<T> {
     pub unsafe fn from_raw(ptr: *const T) -> Self {
         // To find the corresponding pointer to the `RcBox` we need to subtract the offset of the
         // `value` field from the pointer.
-        Rc { ptr: Shared::new((ptr as *const u8).offset(-offset_of!(RcBox<T>, value)) as *const _) }
+
+        let ptr = (ptr as *const u8).offset(-offset_of!(RcBox<T>, value));
+        Rc {
+            ptr: Shared::new(ptr as *mut u8 as *mut _)
+        }
     }
 }
 
@@ -451,7 +455,7 @@ impl<T> Rc<[T]> {
             // Free the original allocation without freeing its (moved) contents.
             box_free(Box::into_raw(value));
 
-            Rc { ptr: Shared::new(ptr as *const _) }
+            Rc { ptr: Shared::new(ptr as *mut _) }
         }
     }
 }
@@ -553,8 +557,9 @@ impl<T: ?Sized> Rc<T> {
     #[stable(feature = "rc_unique", since = "1.4.0")]
     pub fn get_mut(this: &mut Self) -> Option<&mut T> {
         if Rc::is_unique(this) {
-            let inner = unsafe { &mut *this.ptr.as_mut_ptr() };
+            unsafe {
-            Some(&mut inner.value)
+                Some(&mut this.ptr.as_mut().value)
+            }
         } else {
             None
         }
@@ -578,9 +583,7 @@ impl<T: ?Sized> Rc<T> {
     /// assert!(!Rc::ptr_eq(&five, &other_five));
     /// ```
     pub fn ptr_eq(this: &Self, other: &Self) -> bool {
-        let this_ptr: *const RcBox<T> = *this.ptr;
+        this.ptr.as_ptr() == other.ptr.as_ptr()
-        let other_ptr: *const RcBox<T> = *other.ptr;
-        this_ptr == other_ptr
     }
 }
 
@@ -623,7 +626,7 @@ impl<T: Clone> Rc<T> {
         } else if Rc::weak_count(this) != 0 {
             // Can just steal the data, all that's left is Weaks
             unsafe {
-                let mut swap = Rc::new(ptr::read(&(**this.ptr).value));
+                let mut swap = Rc::new(ptr::read(&this.ptr.as_ref().value));
                 mem::swap(this, &mut swap);
                 swap.dec_strong();
                 // Remove implicit strong-weak ref (no need to craft a fake
@@ -637,8 +640,9 @@ impl<T: Clone> Rc<T> {
         // reference count is guaranteed to be 1 at this point, and we required
         // the `Rc<T>` itself to be `mut`, so we're returning the only possible
         // reference to the inner value.
-        let inner = unsafe { &mut *this.ptr.as_mut_ptr() };
+        unsafe {
-        &mut inner.value
+            &mut this.ptr.as_mut().value
+        }
     }
 }
 
@@ -683,12 +687,12 @@ unsafe impl<#[may_dangle] T: ?Sized> Drop for Rc<T> {
     /// ```
     fn drop(&mut self) {
         unsafe {
-            let ptr = self.ptr.as_mut_ptr();
+            let ptr = self.ptr.as_ptr();
 
             self.dec_strong();
             if self.strong() == 0 {
                 // destroy the contained object
-                ptr::drop_in_place(&mut (*ptr).value);
+                ptr::drop_in_place(self.ptr.as_mut());
 
                 // remove the implicit "strong weak" pointer now that we've
                 // destroyed the contents.
@@ -925,7 +929,7 @@ impl<T: ?Sized + fmt::Debug> fmt::Debug for Rc<T> {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<T: ?Sized> fmt::Pointer for Rc<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        fmt::Pointer::fmt(&*self.ptr, f)
+        fmt::Pointer::fmt(&self.ptr, f)
     }
 }
 
@@ -1067,7 +1071,7 @@ impl<T: ?Sized> Drop for Weak<T> {
     /// ```
     fn drop(&mut self) {
         unsafe {
-            let ptr = *self.ptr;
+            let ptr = self.ptr.as_ptr();
 
             self.dec_weak();
             // the weak count starts at 1, and will only go to zero if all
@@ -1175,12 +1179,7 @@ impl<T: ?Sized> RcBoxPtr<T> for Rc<T> {
     #[inline(always)]
     fn inner(&self) -> &RcBox<T> {
         unsafe {
-            // Safe to assume this here, as if it weren't true, we'd be breaking
+            self.ptr.as_ref()
-            // the contract anyway.
-            // This allows the null check to be elided in the destructor if we
-            // manipulated the reference count in the same function.
-            assume(!(*(&self.ptr as *const _ as *const *const ())).is_null());
-            &(**self.ptr)
         }
     }
 }
@@ -1189,12 +1188,7 @@ impl<T: ?Sized> RcBoxPtr<T> for Weak<T> {
     #[inline(always)]
     fn inner(&self) -> &RcBox<T> {
         unsafe {
-            // Safe to assume this here, as if it weren't true, we'd be breaking
+            self.ptr.as_ref()
-            // the contract anyway.
-            // This allows the null check to be elided in the destructor if we
-            // manipulated the reference count in the same function.
-            assume(!(*(&self.ptr as *const _ as *const *const ())).is_null());
-            &(**self.ptr)
         }
     }
 }

src/libarena/lib.rs

@@ -31,7 +31,6 @@
 #![feature(alloc)]
 #![feature(core_intrinsics)]
 #![feature(dropck_eyepatch)]
-#![feature(heap_api)]
 #![feature(generic_param_attrs)]
 #![feature(staged_api)]
 #![cfg_attr(test, feature(test))]
@@ -48,7 +47,6 @@ use std::mem;
 use std::ptr;
 use std::slice;
 
-use alloc::heap;
 use alloc::raw_vec::RawVec;
 
 /// An arena that can hold objects of only one type.
@@ -140,7 +138,7 @@ impl<T> TypedArena<T> {
         unsafe {
             if mem::size_of::<T>() == 0 {
                 self.ptr.set(intrinsics::arith_offset(self.ptr.get() as *mut u8, 1) as *mut T);
-                let ptr = heap::EMPTY as *mut T;
+                let ptr = mem::align_of::<T>() as *mut T;
                 // Don't drop the object. This `write` is equivalent to `forget`.
                 ptr::write(ptr, object);
                 &mut *ptr

src/libcollections/btree/node.rs

@@ -152,12 +152,12 @@ impl<K, V> BoxedNode<K, V> {
     }
 
     unsafe fn from_ptr(ptr: NonZero<*const LeafNode<K, V>>) -> Self {
-        BoxedNode { ptr: Unique::new(*ptr as *mut LeafNode<K, V>) }
+        BoxedNode { ptr: Unique::new(ptr.get() as *mut LeafNode<K, V>) }
     }
 
     fn as_ptr(&self) -> NonZero<*const LeafNode<K, V>> {
         unsafe {
-            NonZero::new(*self.ptr as *const LeafNode<K, V>)
+            NonZero::new(self.ptr.as_ptr())
         }
     }
 }
@@ -241,7 +241,7 @@ impl<K, V> Root<K, V> {
     pub fn pop_level(&mut self) {
         debug_assert!(self.height > 0);
 
-        let top = *self.node.ptr as *mut u8;
+        let top = self.node.ptr.as_ptr() as *mut u8;
 
         self.node = unsafe {
             BoxedNode::from_ptr(self.as_mut()
@@ -308,7 +308,7 @@ unsafe impl<K: Send, V: Send, Type> Send
 impl<BorrowType, K, V> NodeRef<BorrowType, K, V, marker::Internal> {
     fn as_internal(&self) -> &InternalNode<K, V> {
         unsafe {
-            &*(*self.node as *const InternalNode<K, V>)
+            &*(self.node.get() as *const InternalNode<K, V>)
         }
     }
 }
@@ -316,7 +316,7 @@ impl<BorrowType, K, V> NodeRef<BorrowType, K, V, marker::Internal> {
 impl<'a, K, V> NodeRef<marker::Mut<'a>, K, V, marker::Internal> {
     fn as_internal_mut(&mut self) -> &mut InternalNode<K, V> {
         unsafe {
-            &mut *(*self.node as *mut InternalNode<K, V>)
+            &mut *(self.node.get() as *mut InternalNode<K, V>)
         }
     }
 }
@@ -358,7 +358,7 @@ impl<BorrowType, K, V, Type> NodeRef<BorrowType, K, V, Type> {
 
     fn as_leaf(&self) -> &LeafNode<K, V> {
         unsafe {
-            &**self.node
+            &*self.node.get()
         }
     }
 
@@ -510,7 +510,7 @@ impl<'a, K, V, Type> NodeRef<marker::Mut<'a>, K, V, Type> {
 
     fn as_leaf_mut(&mut self) -> &mut LeafNode<K, V> {
         unsafe {
-            &mut *(*self.node as *mut LeafNode<K, V>)
+            &mut *(self.node.get() as *mut LeafNode<K, V>)
         }
     }
 
@@ -1253,13 +1253,13 @@ impl<'a, K, V> Handle<NodeRef<marker::Mut<'a>, K, V, marker::Internal>, marker::
                 }
 
                 heap::deallocate(
-                    *right_node.node as *mut u8,
+                    right_node.node.get() as *mut u8,
                     mem::size_of::<InternalNode<K, V>>(),
                     mem::align_of::<InternalNode<K, V>>()
                 );
             } else {
                 heap::deallocate(
-                    *right_node.node as *mut u8,
+                    right_node.node.get() as *mut u8,
                     mem::size_of::<LeafNode<K, V>>(),
                     mem::align_of::<LeafNode<K, V>>()
                 );

src/libcollections/linked_list.rs

@@ -161,7 +161,7 @@ impl<T> LinkedList<T> {
 
             match self.head {
                 None => self.tail = node,
-                Some(head) => (*head.as_mut_ptr()).prev = node,
+                Some(mut head) => head.as_mut().prev = node,
             }
 
             self.head = node;
@@ -173,12 +173,12 @@ impl<T> LinkedList<T> {
     #[inline]
     fn pop_front_node(&mut self) -> Option<Box<Node<T>>> {
         self.head.map(|node| unsafe {
-            let node = Box::from_raw(node.as_mut_ptr());
+            let node = Box::from_raw(node.as_ptr());
             self.head = node.next;
 
             match self.head {
                 None => self.tail = None,
-                Some(head) => (*head.as_mut_ptr()).prev = None,
+                Some(mut head) => head.as_mut().prev = None,
             }
 
             self.len -= 1;
@@ -196,7 +196,7 @@ impl<T> LinkedList<T> {
 
             match self.tail {
                 None => self.head = node,
-                Some(tail) => (*tail.as_mut_ptr()).next = node,
+                Some(mut tail) => tail.as_mut().next = node,
             }
 
             self.tail = node;
@@ -208,12 +208,12 @@ impl<T> LinkedList<T> {
     #[inline]
     fn pop_back_node(&mut self) -> Option<Box<Node<T>>> {
         self.tail.map(|node| unsafe {
-            let node = Box::from_raw(node.as_mut_ptr());
+            let node = Box::from_raw(node.as_ptr());
             self.tail = node.prev;
 
             match self.tail {
                 None => self.head = None,
-                Some(tail) => (*tail.as_mut_ptr()).next = None,
+                Some(mut tail) => tail.as_mut().next = None,
             }
 
             self.len -= 1;
@@ -285,11 +285,11 @@ impl<T> LinkedList<T> {
     pub fn append(&mut self, other: &mut Self) {
         match self.tail {
             None => mem::swap(self, other),
-            Some(tail) => {
+            Some(mut tail) => {
-                if let Some(other_head) = other.head.take() {
+                if let Some(mut other_head) = other.head.take() {
                     unsafe {
-                        (*tail.as_mut_ptr()).next = Some(other_head);
+                        tail.as_mut().next = Some(other_head);
-                        (*other_head.as_mut_ptr()).prev = Some(tail);
+                        other_head.as_mut().prev = Some(tail);
                     }
 
                     self.tail = other.tail.take();
@@ -477,7 +477,9 @@ impl<T> LinkedList<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn front(&self) -> Option<&T> {
-        self.head.map(|node| unsafe { &(**node).element })
+        unsafe {
+            self.head.as_ref().map(|node| &node.as_ref().element)
+        }
     }
 
     /// Provides a mutable reference to the front element, or `None` if the list
@@ -503,7 +505,9 @@ impl<T> LinkedList<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn front_mut(&mut self) -> Option<&mut T> {
-        self.head.map(|node| unsafe { &mut (*node.as_mut_ptr()).element })
+        unsafe {
+            self.head.as_mut().map(|node| &mut node.as_mut().element)
+        }
     }
 
     /// Provides a reference to the back element, or `None` if the list is
@@ -523,7 +527,9 @@ impl<T> LinkedList<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn back(&self) -> Option<&T> {
-        self.tail.map(|node| unsafe { &(**node).element })
+        unsafe {
+            self.tail.as_ref().map(|node| &node.as_ref().element)
+        }
     }
 
     /// Provides a mutable reference to the back element, or `None` if the list
@@ -549,7 +555,9 @@ impl<T> LinkedList<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn back_mut(&mut self) -> Option<&mut T> {
-        self.tail.map(|node| unsafe { &mut (*node.as_mut_ptr()).element })
+        unsafe {
+            self.tail.as_mut().map(|node| &mut node.as_mut().element)
+        }
     }
 
     /// Adds an element first in the list.
@@ -694,9 +702,9 @@ impl<T> LinkedList<T> {
         let second_part_head;
 
         unsafe {
-            second_part_head = (*split_node.unwrap().as_mut_ptr()).next.take();
+            second_part_head = split_node.unwrap().as_mut().next.take();
-            if let Some(head) = second_part_head {
+            if let Some(mut head) = second_part_head {
-                (*head.as_mut_ptr()).prev = None;
+                head.as_mut().prev = None;
             }
         }
 
@@ -788,7 +796,8 @@ impl<'a, T> Iterator for Iter<'a, T> {
             None
         } else {
             self.head.map(|node| unsafe {
-                let node = &**node;
+                // Need an unbound lifetime to get 'a
+                let node = &*node.as_ptr();
                 self.len -= 1;
                 self.head = node.next;
                 &node.element
@@ -810,7 +819,8 @@ impl<'a, T> DoubleEndedIterator for Iter<'a, T> {
             None
         } else {
             self.tail.map(|node| unsafe {
-                let node = &**node;
+                // Need an unbound lifetime to get 'a
+                let node = &*node.as_ptr();
                 self.len -= 1;
                 self.tail = node.prev;
                 &node.element
@@ -835,7 +845,8 @@ impl<'a, T> Iterator for IterMut<'a, T> {
             None
         } else {
             self.head.map(|node| unsafe {
-                let node = &mut *node.as_mut_ptr();
+                // Need an unbound lifetime to get 'a
+                let node = &mut *node.as_ptr();
                 self.len -= 1;
                 self.head = node.next;
                 &mut node.element
@@ -857,7 +868,8 @@ impl<'a, T> DoubleEndedIterator for IterMut<'a, T> {
             None
         } else {
             self.tail.map(|node| unsafe {
-                let node = &mut *node.as_mut_ptr();
+                // Need an unbound lifetime to get 'a
+                let node = &mut *node.as_ptr();
                 self.len -= 1;
                 self.tail = node.prev;
                 &mut node.element
@@ -903,8 +915,8 @@ impl<'a, T> IterMut<'a, T> {
     pub fn insert_next(&mut self, element: T) {
         match self.head {
             None => self.list.push_back(element),
-            Some(head) => unsafe {
+            Some(mut head) => unsafe {
-                let prev = match (**head).prev {
+                let mut prev = match head.as_ref().prev {
                     None => return self.list.push_front(element),
                     Some(prev) => prev,
                 };
@@ -915,8 +927,8 @@ impl<'a, T> IterMut<'a, T> {
                     element: element,
                 })));
 
-                (*prev.as_mut_ptr()).next = node;
+                prev.as_mut().next = node;
-                (*head.as_mut_ptr()).prev = node;
+                head.as_mut().prev = node;
 
                 self.list.len += 1;
             },
@@ -948,7 +960,9 @@ impl<'a, T> IterMut<'a, T> {
         if self.len == 0 {
             None
         } else {
-            self.head.map(|node| unsafe { &mut (*node.as_mut_ptr()).element })
+            unsafe {
+                self.head.as_mut().map(|node| &mut node.as_mut().element)
+            }
         }
     }
 }
@@ -1276,21 +1290,21 @@ mod tests {
                     assert_eq!(0, list.len);
                     return;
                 }
-                Some(node) => node_ptr = &**node,
+                Some(node) => node_ptr = &*node.as_ptr(),
             }
             loop {
                 match (last_ptr, node_ptr.prev) {
                     (None, None) => {}
                     (None, _) => panic!("prev link for head"),
                     (Some(p), Some(pptr)) => {
-                        assert_eq!(p as *const Node<T>, *pptr as *const Node<T>);
+                        assert_eq!(p as *const Node<T>, pptr.as_ptr() as *const Node<T>);
                     }
                     _ => panic!("prev link is none, not good"),
                 }
                 match node_ptr.next {
                     Some(next) => {
                         last_ptr = Some(node_ptr);
-                        node_ptr = &**next;
+                        node_ptr = &*next.as_ptr();
                         len += 1;
                     }
                     None => {

src/libcollections/vec.rs

@@ -67,7 +67,6 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 
 use alloc::boxed::Box;
-use alloc::heap::EMPTY;
 use alloc::raw_vec::RawVec;
 use borrow::ToOwned;
 use borrow::Cow;
@@ -1776,9 +1775,9 @@ impl<T> SpecExtend<T, IntoIter<T>> for Vec<T> {
         // A common case is passing a vector into a function which immediately
         // re-collects into a vector. We can short circuit this if the IntoIter
         // has not been advanced at all.
-        if *iterator.buf == iterator.ptr as *mut T {
+        if iterator.buf.as_ptr() as *const _ == iterator.ptr {
             unsafe {
-                let vec = Vec::from_raw_parts(*iterator.buf as *mut T,
+                let vec = Vec::from_raw_parts(iterator.buf.as_ptr(),
                                               iterator.len(),
                                               iterator.cap);
                 mem::forget(iterator);
@@ -2192,7 +2191,8 @@ impl<T> Iterator for IntoIter<T> {
                     self.ptr = arith_offset(self.ptr as *const i8, 1) as *mut T;
 
                     // Use a non-null pointer value
-                    Some(ptr::read(EMPTY as *mut T))
+                    // (self.ptr might be null because of wrapping)
+                    Some(ptr::read(1 as *mut T))
                 } else {
                     let old = self.ptr;
                     self.ptr = self.ptr.offset(1);
@@ -2231,7 +2231,8 @@ impl<T> DoubleEndedIterator for IntoIter<T> {
                     self.end = arith_offset(self.end as *const i8, -1) as *mut T;
 
                     // Use a non-null pointer value
-                    Some(ptr::read(EMPTY as *mut T))
+                    // (self.end might be null because of wrapping)
+                    Some(ptr::read(1 as *mut T))
                 } else {
                     self.end = self.end.offset(-1);
 
@@ -2269,7 +2270,7 @@ unsafe impl<#[may_dangle] T> Drop for IntoIter<T> {
         for _x in self.by_ref() {}
 
         // RawVec handles deallocation
-        let _ = unsafe { RawVec::from_raw_parts(self.buf.as_mut_ptr(), self.cap) };
+        let _ = unsafe { RawVec::from_raw_parts(self.buf.as_ptr(), self.cap) };
     }
 }
 
@@ -2334,7 +2335,7 @@ impl<'a, T> Drop for Drain<'a, T> {
 
         if self.tail_len > 0 {
             unsafe {
-                let source_vec = &mut *self.vec.as_mut_ptr();
+                let source_vec = self.vec.as_mut();
                 // memmove back untouched tail, update to new length
                 let start = source_vec.len();
                 let tail = self.tail_start;
@@ -2456,8 +2457,7 @@ impl<'a, I: Iterator> Drop for Splice<'a, I> {
 
         unsafe {
             if self.drain.tail_len == 0 {
-                let vec = &mut *self.drain.vec.as_mut_ptr();
+                self.drain.vec.as_mut().extend(self.replace_with.by_ref());
-                vec.extend(self.replace_with.by_ref());
                 return
             }
 
@@ -2498,7 +2498,7 @@ impl<'a, T> Drain<'a, T> {
     /// Fill that range as much as possible with new elements from the `replace_with` iterator.
     /// Return whether we filled the entire range. (`replace_with.next()` didn’t return `None`.)
     unsafe fn fill<I: Iterator<Item=T>>(&mut self, replace_with: &mut I) -> bool {
-        let vec = &mut *self.vec.as_mut_ptr();
+        let vec = self.vec.as_mut();
         let range_start = vec.len;
         let range_end = self.tail_start;
         let range_slice = slice::from_raw_parts_mut(
@@ -2518,7 +2518,7 @@ impl<'a, T> Drain<'a, T> {
 
     /// Make room for inserting more elements before the tail.
     unsafe fn move_tail(&mut self, extra_capacity: usize) {
-        let vec = &mut *self.vec.as_mut_ptr();
+        let vec = self.vec.as_mut();
         let used_capacity = self.tail_start + self.tail_len;
         vec.buf.reserve(used_capacity, extra_capacity);
 

src/libcollections/vec_deque.rs

@@ -2160,7 +2160,7 @@ impl<'a, T: 'a> Drop for Drain<'a, T> {
     fn drop(&mut self) {
         for _ in self.by_ref() {}
 
-        let source_deque = unsafe { &mut *self.deque.as_mut_ptr() };
+        let source_deque = unsafe { self.deque.as_mut() };
 
         // T = source_deque_tail; H = source_deque_head; t = drain_tail; h = drain_head
         //

src/libcore/cell.rs

@@ -132,7 +132,6 @@
 //! use std::cell::Cell;
 //! use std::ptr::Shared;
 //! use std::intrinsics::abort;
-//! use std::intrinsics::assume;
 //!
 //! struct Rc<T: ?Sized> {
 //!     ptr: Shared<RcBox<T>>
@@ -171,8 +170,7 @@
 //! impl<T: ?Sized> RcBoxPtr<T> for Rc<T> {
 //!    fn inner(&self) -> &RcBox<T> {
 //!        unsafe {
-//!            assume(!(*(&self.ptr as *const _ as *const *const ())).is_null());
+//!            self.ptr.as_ref()
-//!            &(**self.ptr)
 //!        }
 //!    }
 //! }

src/libcore/nonzero.rs

@@ -13,7 +13,7 @@
             reason = "needs an RFC to flesh out the design",
             issue = "27730")]
 
-use ops::{CoerceUnsized, Deref};
+use ops::CoerceUnsized;
 
 /// Unsafe trait to indicate what types are usable with the NonZero struct
 pub unsafe trait Zeroable {}
@@ -46,15 +46,10 @@ impl<T: Zeroable> NonZero<T> {
     pub const unsafe fn new(inner: T) -> NonZero<T> {
         NonZero(inner)
     }
-}
 
-impl<T: Zeroable> Deref for NonZero<T> {
+    /// Gets the inner value.
-    type Target = T;
+    pub fn get(self) -> T {
-
+        self.0
-    #[inline]
-    fn deref(&self) -> &T {
-        let NonZero(ref inner) = *self;
-        inner
     }
 }
 

src/libcore/ptr.rs

@@ -17,7 +17,7 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 
 use intrinsics;
-use ops::{CoerceUnsized, Deref};
+use ops::CoerceUnsized;
 use fmt;
 use hash;
 use marker::{PhantomData, Unsize};
@@ -957,13 +957,25 @@ impl<T: ?Sized> PartialOrd for *mut T {
 }
 
 /// A wrapper around a raw non-null `*mut T` that indicates that the possessor
-/// of this wrapper owns the referent. This in turn implies that the
+/// of this wrapper owns the referent. Useful for building abstractions like
-/// `Unique<T>` is `Send`/`Sync` if `T` is `Send`/`Sync`, unlike a raw
+/// `Box<T>`, `Vec<T>`, `String`, and `HashMap<K, V>`.
-/// `*mut T` (which conveys no particular ownership semantics).  It
+///
-/// also implies that the referent of the pointer should not be
+/// Unlike `*mut T`, `Unique<T>` behaves "as if" it were an instance of `T`.
-/// modified without a unique path to the `Unique` reference. Useful
+/// It implements `Send`/`Sync` if `T` is `Send`/`Sync`. It also implies
-/// for building abstractions like `Vec<T>` or `Box<T>`, which
+/// the kind of strong aliasing guarantees an instance of `T` can expect:
-/// internally use raw pointers to manage the memory that they own.
+/// the referent of the pointer should not be modified without a unique path to
+/// its owning Unique.
+///
+/// If you're uncertain of whether it's correct to use `Unique` for your purposes,
+/// consider using `Shared`, which has weaker semantics.
+///
+/// Unlike `*mut T`, the pointer must always be non-null, even if the pointer
+/// is never dereferenced. This is so that enums may use this forbidden value
+/// as a discriminant -- `Option<Unique<T>>` has the same size as `Unique<T>`.
+/// However the pointer may still dangle if it isn't dereferenced.
+///
+/// Unlike `*mut T`, `Unique<T>` is covariant over `T`. This should always be correct
+/// for any type which upholds Unique's aliasing requirements.
 #[allow(missing_debug_implementations)]
 #[unstable(feature = "unique", reason = "needs an RFC to flesh out design",
            issue = "27730")]
@@ -991,6 +1003,20 @@ unsafe impl<T: Send + ?Sized> Send for Unique<T> { }
 #[unstable(feature = "unique", issue = "27730")]
 unsafe impl<T: Sync + ?Sized> Sync for Unique<T> { }
 
+#[unstable(feature = "unique", issue = "27730")]
+impl<T: Sized> Unique<T> {
+    /// Creates a new `Shared` that is dangling, but well-aligned.
+    ///
+    /// This is useful for initializing types which lazily allocate, like
+    /// `Vec::new` does.
+    pub fn empty() -> Self {
+        unsafe {
+            let ptr = mem::align_of::<T>() as *mut T;
+            Unique::new(ptr)
+        }
+    }
+}
+
 #[unstable(feature = "unique", issue = "27730")]
 impl<T: ?Sized> Unique<T> {
     /// Creates a new `Unique`.
@@ -1002,41 +1028,72 @@ impl<T: ?Sized> Unique<T> {
         Unique { pointer: NonZero::new(ptr), _marker: PhantomData }
     }
 
+    /// Acquires the underlying `*mut` pointer.
+    pub fn as_ptr(self) -> *mut T {
+        self.pointer.get() as *mut T
+    }
+
     /// Dereferences the content.
-    pub unsafe fn get(&self) -> &T {
+    ///
-        &**self.pointer
+    /// The resulting lifetime is bound to self so this behaves "as if"
+    /// it were actually an instance of T that is getting borrowed. If a longer
+    /// (unbound) lifetime is needed, use `&*my_ptr.ptr()`.
+    pub unsafe fn as_ref(&self) -> &T {
+        &*self.as_ptr()
     }
 
     /// Mutably dereferences the content.
-    pub unsafe fn get_mut(&mut self) -> &mut T {
+    ///
-        &mut ***self
+    /// The resulting lifetime is bound to self so this behaves "as if"
+    /// it were actually an instance of T that is getting borrowed. If a longer
+    /// (unbound) lifetime is needed, use `&mut *my_ptr.ptr()`.
+    pub unsafe fn as_mut(&mut self) -> &mut T {
+        &mut *self.as_ptr()
     }
 }
 
+#[unstable(feature = "shared", issue = "27730")]
+impl<T: ?Sized> Clone for Unique<T> {
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+#[unstable(feature = "shared", issue = "27730")]
+impl<T: ?Sized> Copy for Unique<T> { }
+
 #[unstable(feature = "unique", issue = "27730")]
 impl<T: ?Sized, U: ?Sized> CoerceUnsized<Unique<U>> for Unique<T> where T: Unsize<U> { }
 
-#[unstable(feature = "unique", issue= "27730")]
-impl<T:?Sized> Deref for Unique<T> {
-    type Target = *mut T;
-
-    #[inline]
-    fn deref(&self) -> &*mut T {
-        unsafe { mem::transmute(&*self.pointer) }
-    }
-}
-
 #[unstable(feature = "unique", issue = "27730")]
-impl<T> fmt::Pointer for Unique<T> {
+impl<T: ?Sized> fmt::Pointer for Unique<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        fmt::Pointer::fmt(&*self.pointer, f)
+        fmt::Pointer::fmt(&self.as_ptr(), f)
     }
 }
 
-/// A wrapper around a raw non-null `*mut T` that indicates that the possessor
+/// A wrapper around a raw `*mut T` that indicates that the possessor
 /// of this wrapper has shared ownership of the referent. Useful for
-/// building abstractions like `Rc<T>` or `Arc<T>`, which internally
+/// building abstractions like `Rc<T>`, `Arc<T>`, or doubly-linked lists, which
-/// use raw pointers to manage the memory that they own.
+/// internally use aliased raw pointers to manage the memory that they own.
+///
+/// This is similar to `Unique`, except that it doesn't make any aliasing
+/// guarantees, and doesn't derive Send and Sync. Note that unlike `&T`,
+/// Shared has no special mutability requirements. Shared may mutate data
+/// aliased by other Shared pointers. More precise rules require Rust to
+/// develop an actual aliasing model.
+///
+/// Unlike `*mut T`, the pointer must always be non-null, even if the pointer
+/// is never dereferenced. This is so that enums may use this forbidden value
+/// as a discriminant -- `Option<Shared<T>>` has the same size as `Shared<T>`.
+/// However the pointer may still dangle if it isn't dereferenced.
+///
+/// Unlike `*mut T`, `Shared<T>` is covariant over `T`. If this is incorrect
+/// for your use case, you should include some PhantomData in your type to
+/// provide invariance, such as `PhantomData<Cell<T>>` or `PhantomData<&'a mut T>`.
+/// Usually this won't be necessary; covariance is correct for Rc, Arc, and LinkedList
+/// because they provide a public API that follows the normal shared XOR mutable
+/// rules of Rust.
 #[allow(missing_debug_implementations)]
 #[unstable(feature = "shared", reason = "needs an RFC to flesh out design",
            issue = "27730")]
@@ -1060,6 +1117,20 @@ impl<T: ?Sized> !Send for Shared<T> { }
 #[unstable(feature = "shared", issue = "27730")]
 impl<T: ?Sized> !Sync for Shared<T> { }
 
+#[unstable(feature = "shared", issue = "27730")]
+impl<T: Sized> Shared<T> {
+    /// Creates a new `Shared` that is dangling, but well-aligned.
+    ///
+    /// This is useful for initializing types which lazily allocate, like
+    /// `Vec::new` does.
+    pub fn empty() -> Self {
+        unsafe {
+            let ptr = mem::align_of::<T>() as *mut T;
+            Shared::new(ptr)
+        }
+    }
+}
+
 #[unstable(feature = "shared", issue = "27730")]
 impl<T: ?Sized> Shared<T> {
     /// Creates a new `Shared`.
@@ -1067,16 +1138,38 @@ impl<T: ?Sized> Shared<T> {
     /// # Safety
     ///
     /// `ptr` must be non-null.
-    pub unsafe fn new(ptr: *const T) -> Self {
+    pub unsafe fn new(ptr: *mut T) -> Self {
         Shared { pointer: NonZero::new(ptr), _marker: PhantomData }
     }
-}
 
-#[unstable(feature = "shared", issue = "27730")]
+    /// Acquires the underlying `*mut` pointer.
-impl<T: ?Sized> Shared<T> {
+    pub fn as_ptr(self) -> *mut T {
+        self.pointer.get() as *mut T
+    }
+
+    /// Dereferences the content.
+    ///
+    /// The resulting lifetime is bound to self so this behaves "as if"
+    /// it were actually an instance of T that is getting borrowed. If a longer
+    /// (unbound) lifetime is needed, use `&*my_ptr.ptr()`.
+    pub unsafe fn as_ref(&self) -> &T {
+        &*self.as_ptr()
+    }
+
+    /// Mutably dereferences the content.
+    ///
+    /// The resulting lifetime is bound to self so this behaves "as if"
+    /// it were actually an instance of T that is getting borrowed. If a longer
+    /// (unbound) lifetime is needed, use `&mut *my_ptr.ptr_mut()`.
+    pub unsafe fn as_mut(&mut self) -> &mut T {
+        &mut *self.as_ptr()
+    }
+
     /// Acquires the underlying pointer as a `*mut` pointer.
+    #[rustc_deprecated(since = "1.19", reason = "renamed to `as_ptr` for ergonomics/consistency")]
+    #[unstable(feature = "shared", issue = "27730")]
     pub unsafe fn as_mut_ptr(&self) -> *mut T {
-        **self as _
+        self.as_ptr()
     }
 }
 
@@ -1094,18 +1187,8 @@ impl<T: ?Sized> Copy for Shared<T> { }
 impl<T: ?Sized, U: ?Sized> CoerceUnsized<Shared<U>> for Shared<T> where T: Unsize<U> { }
 
 #[unstable(feature = "shared", issue = "27730")]
-impl<T: ?Sized> Deref for Shared<T> {
+impl<T: ?Sized> fmt::Pointer for Shared<T> {
-    type Target = *const T;
-
-    #[inline]
-    fn deref(&self) -> &*const T {
-        unsafe { mem::transmute(&*self.pointer) }
-    }
-}
-
-#[unstable(feature = "shared", issue = "27730")]
-impl<T> fmt::Pointer for Shared<T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        fmt::Pointer::fmt(&*self.pointer, f)
+        fmt::Pointer::fmt(&self.as_ptr(), f)
     }
 }

src/libcore/tests/nonzero.rs

@@ -31,12 +31,12 @@ fn test_match_on_nonzero_option() {
         NonZero::new(42)
     });
     match a {
-        Some(val) => assert_eq!(*val, 42),
+        Some(val) => assert_eq!(val.get(), 42),
         None => panic!("unexpected None while matching on Some(NonZero(_))")
     }
 
     match unsafe { Some(NonZero::new(43)) } {
-        Some(val) => assert_eq!(*val, 43),
+        Some(val) => assert_eq!(val.get(), 43),
         None => panic!("unexpected None while matching on Some(NonZero(_))")
     }
 }

src/libcore/tests/ptr.rs

@@ -166,10 +166,10 @@ fn test_set_memory() {
 
 #[test]
 fn test_unsized_unique() {
-    let xs: &mut [i32] = &mut [1, 2, 3];
+    let xs: &[i32] = &[1, 2, 3];
-    let ptr = unsafe { Unique::new(xs as *mut [i32]) };
+    let ptr = unsafe { Unique::new(xs as *const [i32] as *mut [i32]) };
-    let ys = unsafe { &mut **ptr };
+    let ys = unsafe { ptr.as_ref() };
-    let zs: &mut [i32] = &mut [1, 2, 3];
+    let zs: &[i32] = &[1, 2, 3];
     assert!(ys == zs);
 }
 

src/libflate/lib.rs

@@ -62,14 +62,14 @@ pub struct Bytes {
 impl Deref for Bytes {
     type Target = [u8];
     fn deref(&self) -> &[u8] {
-        unsafe { slice::from_raw_parts(*self.ptr, self.len) }
+        unsafe { slice::from_raw_parts(self.ptr.as_ptr(), self.len) }
     }
 }
 
 impl Drop for Bytes {
     fn drop(&mut self) {
         unsafe {
-            libc::free(*self.ptr as *mut _);
+            libc::free(self.ptr.as_ptr() as *mut _);
         }
     }
 }

src/liblibc

@@ -1 +1 @@
-Subproject commit c34a802d1eb037b44c5252078c7270b5472e0f65
+Subproject commit 03562b0cb26a00f49d4eaf18ca3e49608110b0c8

src/librustc/dep_graph/dep_node.rs

@@ -81,6 +81,7 @@ pub enum DepNode<D: Clone + Debug> {
     TransCrateItem(D),
     TransInlinedItem(D),
     TransWriteMetadata,
+    CrateVariances,
 
     // Nodes representing bits of computed IR in the tcx. Each shared
     // table in the tcx (or elsewhere) maps to one of these
@@ -89,6 +90,8 @@ pub enum DepNode<D: Clone + Debug> {
     // predicates for an item wind up in `ItemSignature`).
     AssociatedItems(D),
     ItemSignature(D),
+    ItemVarianceConstraints(D),
+    ItemVariances(D),
     IsForeignItem(D),
     TypeParamPredicates((D, D)),
     SizedConstraint(D),
@@ -180,6 +183,7 @@ impl<D: Clone + Debug> DepNode<D> {
             TransCrateItem,
             AssociatedItems,
             ItemSignature,
+            ItemVariances,
             IsForeignItem,
             AssociatedItemDefIds,
             InherentImpls,
@@ -201,6 +205,7 @@ impl<D: Clone + Debug> DepNode<D> {
             MirKrate => Some(MirKrate),
             TypeckBodiesKrate => Some(TypeckBodiesKrate),
             Coherence => Some(Coherence),
+            CrateVariances => Some(CrateVariances),
             Resolve => Some(Resolve),
             Variance => Some(Variance),
             PrivacyAccessLevels(k) => Some(PrivacyAccessLevels(k)),
@@ -232,6 +237,8 @@ impl<D: Clone + Debug> DepNode<D> {
             TransInlinedItem(ref d) => op(d).map(TransInlinedItem),
             AssociatedItems(ref d) => op(d).map(AssociatedItems),
             ItemSignature(ref d) => op(d).map(ItemSignature),
+            ItemVariances(ref d) => op(d).map(ItemVariances),
+            ItemVarianceConstraints(ref d) => op(d).map(ItemVarianceConstraints),
             IsForeignItem(ref d) => op(d).map(IsForeignItem),
             TypeParamPredicates((ref item, ref param)) => {
                 Some(TypeParamPredicates((try_opt!(op(item)), try_opt!(op(param)))))

src/librustc/dep_graph/mod.rs

@@ -18,7 +18,6 @@ mod raii;
 mod safe;
 mod shadow;
 mod thread;
-mod visit;
 
 pub use self::dep_tracking_map::{DepTrackingMap, DepTrackingMapConfig};
 pub use self::dep_node::DepNode;
@@ -28,5 +27,4 @@ pub use self::graph::WorkProduct;
 pub use self::query::DepGraphQuery;
 pub use self::safe::AssertDepGraphSafe;
 pub use self::safe::DepGraphSafe;
-pub use self::visit::visit_all_item_likes_in_krate;
 pub use self::raii::DepTask;

src/librustc/dep_graph/visit.rs

@@ -1,77 +0,0 @@
-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use hir;
-use hir::def_id::DefId;
-use hir::itemlikevisit::ItemLikeVisitor;
-use ty::TyCtxt;
-
-use super::dep_node::DepNode;
-
-/// Visit all the items in the krate in some order. When visiting a
-/// particular item, first create a dep-node by calling `dep_node_fn`
-/// and push that onto the dep-graph stack of tasks, and also create a
-/// read edge from the corresponding AST node. This is used in
-/// compiler passes to automatically record the item that they are
-/// working on.
-pub fn visit_all_item_likes_in_krate<'a, 'tcx, V, F>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                                     mut dep_node_fn: F,
-                                                     visitor: &mut V)
-    where F: FnMut(DefId) -> DepNode<DefId>, V: ItemLikeVisitor<'tcx>
-{
-    struct TrackingVisitor<'visit, 'tcx: 'visit, F: 'visit, V: 'visit> {
-        tcx: TyCtxt<'visit, 'tcx, 'tcx>,
-        dep_node_fn: &'visit mut F,
-        visitor: &'visit mut V,
-    }
-
-    impl<'visit, 'tcx, F, V> ItemLikeVisitor<'tcx> for TrackingVisitor<'visit, 'tcx, F, V>
-        where F: FnMut(DefId) -> DepNode<DefId>, V: ItemLikeVisitor<'tcx>
-    {
-        fn visit_item(&mut self, i: &'tcx hir::Item) {
-            let item_def_id = self.tcx.hir.local_def_id(i.id);
-            let task_id = (self.dep_node_fn)(item_def_id);
-            let _task = self.tcx.dep_graph.in_task(task_id.clone());
-            debug!("Started task {:?}", task_id);
-            self.tcx.dep_graph.read(DepNode::Hir(item_def_id));
-            self.visitor.visit_item(i);
-            debug!("Ended task {:?}", task_id);
-        }
-
-        fn visit_trait_item(&mut self, i: &'tcx hir::TraitItem) {
-            let trait_item_def_id = self.tcx.hir.local_def_id(i.id);
-            let task_id = (self.dep_node_fn)(trait_item_def_id);
-            let _task = self.tcx.dep_graph.in_task(task_id.clone());
-            debug!("Started task {:?}", task_id);
-            self.tcx.dep_graph.read(DepNode::Hir(trait_item_def_id));
-            self.visitor.visit_trait_item(i);
-            debug!("Ended task {:?}", task_id);
-        }
-
-        fn visit_impl_item(&mut self, i: &'tcx hir::ImplItem) {
-            let impl_item_def_id = self.tcx.hir.local_def_id(i.id);
-            let task_id = (self.dep_node_fn)(impl_item_def_id);
-            let _task = self.tcx.dep_graph.in_task(task_id.clone());
-            debug!("Started task {:?}", task_id);
-            self.tcx.dep_graph.read(DepNode::Hir(impl_item_def_id));
-            self.visitor.visit_impl_item(i);
-            debug!("Ended task {:?}", task_id);
-        }
-    }
-
-    let krate = tcx.dep_graph.with_ignore(|| tcx.hir.krate());
-    let mut tracking_visitor = TrackingVisitor {
-        tcx: tcx,
-        dep_node_fn: &mut dep_node_fn,
-        visitor: visitor,
-    };
-    krate.visit_all_item_likes(&mut tracking_visitor)
-}
-

src/librustc/hir/intravisit.rs

@@ -88,7 +88,7 @@ pub enum NestedVisitorMap<'this, 'tcx: 'this> {
     /// that are inside of an item-like.
     ///
     /// **This is the most common choice.** A very commmon pattern is
-    /// to use `tcx.visit_all_item_likes_in_krate()` as an outer loop,
+    /// to use `visit_all_item_likes()` as an outer loop,
     /// and to have the visitor that visits the contents of each item
     /// using this setting.
     OnlyBodies(&'this Map<'tcx>),

src/librustc/hir/itemlikevisit.rs

@@ -19,9 +19,8 @@ use super::intravisit::Visitor;
 ///
 /// 1. **Shallow visit**: Get a simple callback for every item (or item-like thing) in the HIR.
 ///    - Example: find all items with a `#[foo]` attribute on them.
-///    - How: Implement `ItemLikeVisitor` and call `tcx.visit_all_item_likes_in_krate()`.
+///    - How: Implement `ItemLikeVisitor` and call `tcx.hir.krate().visit_all_item_likes()`.
 ///    - Pro: Efficient; just walks the lists of item-like things, not the nodes themselves.
-///    - Pro: Integrates well into dependency tracking.
 ///    - Con: Don't get information about nesting
 ///    - Con: Don't have methods for specific bits of HIR, like "on
 ///      every expr, do this".
@@ -30,7 +29,7 @@ use super::intravisit::Visitor;
 ///    within one another.
 ///    - Example: Examine each expression to look for its type and do some check or other.
 ///    - How: Implement `intravisit::Visitor` and use
-///      `tcx.visit_all_item_likes_in_krate(visitor.as_deep_visitor())`. Within
+///      `tcx.hir.krate().visit_all_item_likes(visitor.as_deep_visitor())`. Within
 ///      your `intravisit::Visitor` impl, implement methods like
 ///      `visit_expr()`; don't forget to invoke
 ///      `intravisit::walk_visit_expr()` to keep walking the subparts.

src/librustc/ty/context.rs

@@ -470,9 +470,6 @@ pub struct GlobalCtxt<'tcx> {
 
     pub lang_items: middle::lang_items::LanguageItems,
 
-    /// True if the variance has been computed yet; false otherwise.
-    pub variance_computed: Cell<bool>,
-
     /// Set of used unsafe nodes (functions or blocks). Unsafe nodes not
     /// present in this set can be warned about.
     pub used_unsafe: RefCell<NodeSet>,
@@ -744,7 +741,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             dep_graph: dep_graph.clone(),
             types: common_types,
             named_region_map: named_region_map,
-            variance_computed: Cell::new(false),
             trait_map: resolutions.trait_map,
             export_map: resolutions.export_map,
             fulfilled_predicates: RefCell::new(fulfilled_predicates),

src/librustc/ty/maps.rs

@@ -266,6 +266,12 @@ impl<'tcx> QueryDescription for queries::crate_inherent_impls_overlap_check<'tcx
     }
 }
 
+impl<'tcx> QueryDescription for queries::crate_variances<'tcx> {
+    fn describe(_tcx: TyCtxt, _: CrateNum) -> String {
+        format!("computing the variances for items in this crate")
+    }
+}
+
 impl<'tcx> QueryDescription for queries::mir_shims<'tcx> {
     fn describe(tcx: TyCtxt, def: ty::InstanceDef<'tcx>) -> String {
         format!("generating MIR shim for `{}`",
@@ -549,18 +555,6 @@ macro_rules! define_map_struct {
         }
     };
 
-    // Detect things with the `pub` modifier
-    (tcx: $tcx:tt,
-     input: (([pub $($other_modifiers:tt)*] $attrs:tt $name:tt) $($input:tt)*),
-     output: $output:tt) => {
-        define_map_struct! {
-            tcx: $tcx,
-            ready: ([pub] $attrs $name),
-            input: ($($input)*),
-            output: $output
-        }
-    };
-
     // No modifiers left? This is a private item.
     (tcx: $tcx:tt,
      input: (([] $attrs:tt $name:tt) $($input:tt)*),
@@ -687,9 +681,13 @@ define_maps! { <'tcx>
     /// True if this is a foreign item (i.e., linked via `extern { ... }`).
     [] is_foreign_item: IsForeignItem(DefId) -> bool,
 
+    /// Get a map with the variance of every item; use `item_variance`
+    /// instead.
+    [] crate_variances: crate_variances(CrateNum) -> Rc<ty::CrateVariancesMap>,
+
     /// Maps from def-id of a type or region parameter to its
     /// (inferred) variance.
-    [pub] variances_of: ItemSignature(DefId) -> Rc<Vec<ty::Variance>>,
+    [] variances_of: ItemVariances(DefId) -> Rc<Vec<ty::Variance>>,
 
     /// Maps from an impl/trait def-id to a list of the def-ids of its items
     [] associated_item_def_ids: AssociatedItemDefIds(DefId) -> Rc<Vec<DefId>>,
@@ -825,3 +823,7 @@ fn const_eval_dep_node((def_id, _): (DefId, &Substs)) -> DepNode<DefId> {
 fn mir_keys(_: CrateNum) -> DepNode<DefId> {
     DepNode::MirKeys
 }
+
+fn crate_variances(_: CrateNum) -> DepNode<DefId> {
+    DepNode::CrateVariances
+}

src/librustc/ty/mod.rs

@@ -15,7 +15,7 @@ pub use self::IntVarValue::*;
 pub use self::LvaluePreference::*;
 pub use self::fold::TypeFoldable;
 
-use dep_graph::{self, DepNode};
+use dep_graph::DepNode;
 use hir::{map as hir_map, FreevarMap, TraitMap};
 use hir::def::{Def, CtorKind, ExportMap};
 use hir::def_id::{CrateNum, DefId, DefIndex, CRATE_DEF_INDEX, LOCAL_CRATE};
@@ -55,9 +55,9 @@ use rustc_const_math::ConstInt;
 use rustc_data_structures::accumulate_vec::IntoIter as AccIntoIter;
 use rustc_data_structures::stable_hasher::{StableHasher, StableHasherResult,
                                            HashStable};
+use rustc_data_structures::transitive_relation::TransitiveRelation;
 
 use hir;
-use hir::itemlikevisit::ItemLikeVisitor;
 
 pub use self::sty::{Binder, DebruijnIndex};
 pub use self::sty::{FnSig, PolyFnSig};
@@ -309,6 +309,27 @@ pub enum Variance {
     Bivariant,      // T<A> <: T<B>            -- e.g., unused type parameter
 }
 
+/// The crate variances map is computed during typeck and contains the
+/// variance of every item in the local crate. You should not use it
+/// directly, because to do so will make your pass dependent on the
+/// HIR of every item in the local crate. Instead, use
+/// `tcx.variances_of()` to get the variance for a *particular*
+/// item.
+pub struct CrateVariancesMap {
+    /// This relation tracks the dependencies between the variance of
+    /// various items. In particular, if `a < b`, then the variance of
+    /// `a` depends on the sources of `b`.
+    pub dependencies: TransitiveRelation<DefId>,
+
+    /// For each item with generics, maps to a vector of the variance
+    /// of its generics.  If an item has no generics, it will have no
+    /// entry.
+    pub variances: FxHashMap<DefId, Rc<Vec<ty::Variance>>>,
+
+    /// An empty vector, useful for cloning.
+    pub empty_variance: Rc<Vec<ty::Variance>>,
+}
+
 #[derive(Clone, Copy, Debug, RustcDecodable, RustcEncodable)]
 pub struct MethodCallee<'tcx> {
     /// Impl method ID, for inherent methods, or trait method ID, otherwise.
@@ -2543,14 +2564,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         self.mk_region(ty::ReScope(self.node_extent(id)))
     }
 
-    pub fn visit_all_item_likes_in_krate<V,F>(self,
-                                              dep_node_fn: F,
-                                              visitor: &mut V)
-        where F: FnMut(DefId) -> DepNode<DefId>, V: ItemLikeVisitor<'gcx>
-    {
-        dep_graph::visit_all_item_likes_in_krate(self.global_tcx(), dep_node_fn, visitor);
-    }
-
     /// Looks up the span of `impl_did` if the impl is local; otherwise returns `Err`
     /// with the name of the crate containing the impl.
     pub fn span_of_impl(self, impl_did: DefId) -> Result<Span, Symbol> {

src/librustc/ty/relate.rs

@@ -124,14 +124,8 @@ fn relate_item_substs<'a, 'gcx, 'tcx, R>(relation: &mut R,
            a_subst,
            b_subst);
 
-    let variances;
+    let opt_variances = relation.tcx().variances_of(item_def_id);
-    let opt_variances = if relation.tcx().variance_computed.get() {
+    relate_substs(relation, Some(&opt_variances), a_subst, b_subst)
-        variances = relation.tcx().variances_of(item_def_id);
-        Some(&*variances)
-    } else {
-        None
-    };
-    relate_substs(relation, opt_variances, a_subst, b_subst)
 }
 
 pub fn relate_substs<'a, 'gcx, 'tcx, R>(relation: &mut R,

src/librustc/ty/subst.rs

@@ -72,7 +72,7 @@ impl<'tcx> From<ty::Region<'tcx>> for Kind<'tcx> {
 impl<'tcx> Kind<'tcx> {
     #[inline]
     unsafe fn downcast<T>(self, tag: usize) -> Option<&'tcx T> {
-        let ptr = *self.ptr;
+        let ptr = self.ptr.get();
         if ptr & TAG_MASK == tag {
             Some(&*((ptr & !TAG_MASK) as *const _))
         } else {
@@ -102,7 +102,7 @@ impl<'tcx> fmt::Debug for Kind<'tcx> {
         } else if let Some(r) = self.as_region() {
             write!(f, "{:?}", r)
         } else {
-            write!(f, "<unknwon @ {:p}>", *self.ptr as *const ())
+            write!(f, "<unknwon @ {:p}>", self.ptr.get() as *const ())
         }
     }
 }

src/librustc_borrowck/borrowck/mir/gather_moves.rs

@@ -43,7 +43,7 @@ mod indexes {
                     unsafe { $Index(NonZero::new(idx + 1)) }
                 }
                 fn index(self) -> usize {
-                    *self.0 - 1
+                    self.0.get() - 1
                 }
             }
 

src/librustc_data_structures/array_vec.rs

@@ -255,7 +255,7 @@ impl<'a, A: Array> Drop for Drain<'a, A> {
 
         if self.tail_len > 0 {
             unsafe {
-                let source_array_vec = &mut *self.array_vec.as_mut_ptr();
+                let source_array_vec = self.array_vec.as_mut();
                 // memmove back untouched tail, update to new length
                 let start = source_array_vec.len();
                 let tail = self.tail_start;

src/librustc_data_structures/obligation_forest/node_index.rs

@@ -23,6 +23,6 @@ impl NodeIndex {
     }
 
     pub fn get(self) -> usize {
-        (*self.index - 1) as usize
+        (self.index.get() - 1) as usize
     }
 }

src/librustc_data_structures/transitive_relation.rs

@@ -9,21 +9,23 @@
 // except according to those terms.
 
 use bitvec::BitMatrix;
-use stable_hasher::{HashStable, StableHasher, StableHasherResult};
+use fx::FxHashMap;
 use rustc_serialize::{Encodable, Encoder, Decodable, Decoder};
+use stable_hasher::{HashStable, StableHasher, StableHasherResult};
 use std::cell::RefCell;
 use std::fmt::Debug;
+use std::hash::Hash;
 use std::mem;
 
 
-
 #[derive(Clone)]
-pub struct TransitiveRelation<T: Debug + PartialEq> {
+pub struct TransitiveRelation<T: Clone + Debug + Eq + Hash + Clone> {
-    // List of elements. This is used to map from a T to a usize.  We
+    // List of elements. This is used to map from a T to a usize.
-    // expect domain to be small so just use a linear list versus a
-    // hashmap or something.
     elements: Vec<T>,
 
+    // Maps each element to an index.
+    map: FxHashMap<T, Index>,
+
     // List of base edges in the graph. Require to compute transitive
     // closure.
     edges: Vec<Edge>,
@@ -40,19 +42,20 @@ pub struct TransitiveRelation<T: Debug + PartialEq> {
     closure: RefCell<Option<BitMatrix>>,
 }
 
-#[derive(Clone, PartialEq, PartialOrd, RustcEncodable, RustcDecodable)]
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable)]
 struct Index(usize);
 
-#[derive(Clone, PartialEq, RustcEncodable, RustcDecodable)]
+#[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable)]
 struct Edge {
     source: Index,
     target: Index,
 }
 
-impl<T: Debug + PartialEq> TransitiveRelation<T> {
+impl<T: Clone + Debug + Eq + Hash + Clone> TransitiveRelation<T> {
     pub fn new() -> TransitiveRelation<T> {
         TransitiveRelation {
             elements: vec![],
+            map: FxHashMap(),
             edges: vec![],
             closure: RefCell::new(None),
         }
@@ -63,21 +66,27 @@ impl<T: Debug + PartialEq> TransitiveRelation<T> {
     }
 
     fn index(&self, a: &T) -> Option<Index> {
-        self.elements.iter().position(|e| *e == *a).map(Index)
+        self.map.get(a).cloned()
     }
 
     fn add_index(&mut self, a: T) -> Index {
-        match self.index(&a) {
+        let &mut TransitiveRelation {
-            Some(i) => i,
+            ref mut elements,
-            None => {
+            ref closure,
-                self.elements.push(a);
+            ref mut map,
+            ..
+        } = self;
 
-                // if we changed the dimensions, clear the cache
+        map.entry(a.clone())
-                *self.closure.borrow_mut() = None;
+           .or_insert_with(|| {
+               elements.push(a);
 
-                Index(self.elements.len() - 1)
+               // if we changed the dimensions, clear the cache
-            }
+               *closure.borrow_mut() = None;
-        }
+
+               Index(elements.len() - 1)
+           })
+           .clone()
     }
 
     /// Applies the (partial) function to each edge and returns a new
@@ -85,7 +94,7 @@ impl<T: Debug + PartialEq> TransitiveRelation<T> {
     /// `None`.
     pub fn maybe_map<F, U>(&self, mut f: F) -> Option<TransitiveRelation<U>>
         where F: FnMut(&T) -> Option<U>,
-              U: Debug + PartialEq,
+              U: Clone + Debug + Eq + Hash + Clone,
     {
         let mut result = TransitiveRelation::new();
         for edge in &self.edges {
@@ -125,6 +134,20 @@ impl<T: Debug + PartialEq> TransitiveRelation<T> {
         }
     }
 
+    /// Returns a vector of all things less than `a`.
+    ///
+    /// Really this probably ought to be `impl Iterator<Item=&T>`, but
+    /// I'm too lazy to make that work, and -- given the caching
+    /// strategy -- it'd be a touch tricky anyhow.
+    pub fn less_than(&self, a: &T) -> Vec<&T> {
+        match self.index(a) {
+            Some(a) => self.with_closure(|closure| {
+                closure.iter(a.0).map(|i| &self.elements[i]).collect()
+            }),
+            None => vec![],
+        }
+    }
+
     /// Picks what I am referring to as the "postdominating"
     /// upper-bound for `a` and `b`. This is usually the least upper
     /// bound, but in cases where there is no single least upper
@@ -335,7 +358,7 @@ fn pare_down(candidates: &mut Vec<usize>, closure: &BitMatrix) {
 }
 
 impl<T> Encodable for TransitiveRelation<T>
-    where T: Encodable + Debug + PartialEq
+    where T: Clone + Encodable + Debug + Eq + Hash + Clone
 {
     fn encode<E: Encoder>(&self, s: &mut E) -> Result<(), E::Error> {
         s.emit_struct("TransitiveRelation", 2, |s| {
@@ -347,19 +370,23 @@ impl<T> Encodable for TransitiveRelation<T>
 }
 
 impl<T> Decodable for TransitiveRelation<T>
-    where T: Decodable + Debug + PartialEq
+    where T: Clone + Decodable + Debug + Eq + Hash + Clone
 {
     fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
         d.read_struct("TransitiveRelation", 2, |d| {
-            let elements = d.read_struct_field("elements", 0, |d| Decodable::decode(d))?;
+            let elements: Vec<T> = d.read_struct_field("elements", 0, |d| Decodable::decode(d))?;
             let edges = d.read_struct_field("edges", 1, |d| Decodable::decode(d))?;
-            Ok(TransitiveRelation { elements, edges, closure: RefCell::new(None) })
+            let map = elements.iter()
+                              .enumerate()
+                              .map(|(index, elem)| (elem.clone(), Index(index)))
+                              .collect();
+            Ok(TransitiveRelation { elements, edges, map, closure: RefCell::new(None) })
         })
     }
 }
 
 impl<CTX, T> HashStable<CTX> for TransitiveRelation<T>
-    where T: HashStable<CTX> + PartialEq + Debug
+    where T: HashStable<CTX> + Eq + Debug + Clone + Hash
 {
     fn hash_stable<W: StableHasherResult>(&self,
                                           hcx: &mut CTX,
@@ -369,6 +396,8 @@ impl<CTX, T> HashStable<CTX> for TransitiveRelation<T>
         let TransitiveRelation {
             ref elements,
             ref edges,
+            // "map" is just a copy of elements vec
+            map: _,
             // "closure" is just a copy of the data above
             closure: _
         } = *self;

src/librustc_incremental/assert_dep_graph.rs

@@ -51,7 +51,7 @@ use rustc::ty::TyCtxt;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::graph::{Direction, INCOMING, OUTGOING, NodeIndex};
 use rustc::hir;
-use rustc::hir::itemlikevisit::ItemLikeVisitor;
+use rustc::hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc::ich::{ATTR_IF_THIS_CHANGED, ATTR_THEN_THIS_WOULD_NEED};
 use graphviz::IntoCow;
 use std::env;
@@ -80,7 +80,7 @@ pub fn assert_dep_graph<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
                                           if_this_changed: vec![],
                                           then_this_would_need: vec![] };
         visitor.process_attrs(ast::CRATE_NODE_ID, &tcx.hir.krate().attrs);
-        tcx.hir.krate().visit_all_item_likes(&mut visitor);
+        tcx.hir.krate().visit_all_item_likes(&mut visitor.as_deep_visitor());
         (visitor.if_this_changed, visitor.then_this_would_need)
     };
 
@@ -166,17 +166,29 @@ impl<'a, 'tcx> IfThisChanged<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> ItemLikeVisitor<'tcx> for IfThisChanged<'a, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for IfThisChanged<'a, 'tcx> {
+    fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
+        NestedVisitorMap::OnlyBodies(&self.tcx.hir)
+    }
+
     fn visit_item(&mut self, item: &'tcx hir::Item) {
         self.process_attrs(item.id, &item.attrs);
+        intravisit::walk_item(self, item);
     }
 
     fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
         self.process_attrs(trait_item.id, &trait_item.attrs);
+        intravisit::walk_trait_item(self, trait_item);
     }
 
     fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem) {
         self.process_attrs(impl_item.id, &impl_item.attrs);
+        intravisit::walk_impl_item(self, impl_item);
+    }
+
+    fn visit_struct_field(&mut self, s: &'tcx hir::StructField) {
+        self.process_attrs(s.id, &s.attrs);
+        intravisit::walk_struct_field(self, s);
     }
 }
 

src/librustc_metadata/encoder.rs

@@ -240,8 +240,8 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
 }
 
 impl<'a, 'b: 'a, 'tcx: 'b> EntryBuilder<'a, 'b, 'tcx> {
-    fn encode_item_variances(&mut self, def_id: DefId) -> LazySeq<ty::Variance> {
+    fn encode_variances_of(&mut self, def_id: DefId) -> LazySeq<ty::Variance> {
-        debug!("EntryBuilder::encode_item_variances({:?})", def_id);
+        debug!("EntryBuilder::encode_variances_of({:?})", def_id);
         let tcx = self.tcx;
         self.lazy_seq_from_slice(&tcx.variances_of(def_id))
     }
@@ -824,7 +824,7 @@ impl<'a, 'b: 'a, 'tcx: 'b> EntryBuilder<'a, 'b, 'tcx> {
                 hir::ItemEnum(..) |
                 hir::ItemStruct(..) |
                 hir::ItemUnion(..) |
-                hir::ItemTrait(..) => self.encode_item_variances(def_id),
+                hir::ItemTrait(..) => self.encode_variances_of(def_id),
                 _ => LazySeq::empty(),
             },
             generics: match item.node {

src/librustc_typeck/lib.rs

@@ -293,6 +293,7 @@ pub fn provide(providers: &mut Providers) {
     collect::provide(providers);
     coherence::provide(providers);
     check::provide(providers);
+    variance::provide(providers);
 }
 
 pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>)
@@ -307,9 +308,6 @@ pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>)
 
     })?;
 
-    time(time_passes, "variance inference", ||
-         variance::infer_variance(tcx));
-
     tcx.sess.track_errors(|| {
         time(time_passes, "impl wf inference", ||
              impl_wf_check::impl_wf_check(tcx));
@@ -320,6 +318,11 @@ pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>)
           coherence::check_coherence(tcx));
     })?;
 
+    tcx.sess.track_errors(|| {
+        time(time_passes, "variance testing", ||
+             variance::test::test_variance(tcx));
+    })?;
+
     time(time_passes, "wf checking", || check::check_wf_new(tcx))?;
 
     time(time_passes, "item-types checking", || check::check_item_types(tcx))?;

src/librustc_typeck/variance/README.md

@@ -97,51 +97,29 @@ types involved before considering variance.
 
 #### Dependency graph management
 
-Because variance works in two phases, if we are not careful, we wind
+Because variance is a whole-crate inference, its dependency graph
-up with a muddled mess of a dep-graph. Basically, when gathering up
+can become quite muddled if we are not careful. To resolve this, we refactor
-the constraints, things are fairly well-structured, but then we do a
+into two queries:
-fixed-point iteration and write the results back where they
-belong. You can't give this fixed-point iteration a single task
-because it reads from (and writes to) the variance of all types in the
-crate. In principle, we *could* switch the "current task" in a very
-fine-grained way while propagating constraints in the fixed-point
-iteration and everything would be automatically tracked, but that
-would add some overhead and isn't really necessary anyway.
 
-Instead what we do is to add edges into the dependency graph as we
+- `crate_variances` computes the variance for all items in the current crate.
-construct the constraint set: so, if computing the constraints for
+- `variances_of` accesses the variance for an individual reading; it
-node `X` requires loading the inference variables from node `Y`, then
+  works by requesting `crate_variances` and extracting the relevant data.
-we can add an edge `Y -> X`, since the variance we ultimately infer
+  
-for `Y` will affect the variance we ultimately infer for `X`.
+If you limit yourself to reading `variances_of`, your code will only
+depend then on the inference inferred for that particular item.
 
-At this point, we've basically mirrored the inference graph in the
+Eventually, the goal is to rely on the red-green dependency management
-dependency graph. This means we can just completely ignore the
+algorithm. At the moment, however, we rely instead on a hack, where
-fixed-point iteration, since it is just shuffling values along this
+`variances_of` ignores the dependencies of accessing
-graph. In other words, if we added the fine-grained switching of tasks
+`crate_variances` and instead computes the *correct* dependencies
-I described earlier, all it would show is that we repeatedly read the
+itself. To this end, when we build up the constraints in the system,
-values described by the constraints, but those edges were already
+we also built up a transitive `dependencies` relation as part of the
-added when building the constraints in the first place.
+crate map. A `(X, Y)` pair is added to the map each time we have a
-
+constraint that the variance of some inferred for the item `X` depends
-Here is how this is implemented (at least as of the time of this
+on the variance of some element of `Y`. This is to some extent a
-writing). The associated `DepNode` for the variance map is (at least
+mirroring of the inference graph in the dependency graph. This means
-presently) `Signature(DefId)`. This means that, in `constraints.rs`,
+we can just completely ignore the fixed-point iteration, since it is
-when we visit an item to load up its constraints, we set
+just shuffling values along this graph.
-`Signature(DefId)` as the current task (the "memoization" pattern
-described in the `dep-graph` README). Then whenever we find an
-embedded type or trait, we add a synthetic read of `Signature(DefId)`,
-which covers the variances we will compute for all of its
-parameters. This read is synthetic (i.e., we call
-`variance_map.read()`) because, in fact, the final variance is not yet
-computed -- the read *will* occur (repeatedly) during the fixed-point
-iteration phase.
-
-In fact, we don't really *need* this synthetic read. That's because we
-do wind up looking up the `TypeScheme` or `TraitDef` for all
-references types/traits, and those reads add an edge from
-`Signature(DefId)` (that is, they share the same dep node as
-variance). However, I've kept the synthetic reads in place anyway,
-just for future-proofing (in case we change the dep-nodes in the
-future), and because it makes the intention a bit clearer I think.
 
 ### Addendum: Variance on traits
 

src/librustc_typeck/variance/constraints.rs

@@ -15,6 +15,7 @@
 
 use hir::def_id::DefId;
 use middle::resolve_lifetime as rl;
+use rustc::dep_graph::{AssertDepGraphSafe, DepNode};
 use rustc::ty::subst::Substs;
 use rustc::ty::{self, Ty, TyCtxt};
 use rustc::hir::map as hir_map;
@@ -22,12 +23,12 @@ use syntax::ast;
 use rustc::hir;
 use rustc::hir::itemlikevisit::ItemLikeVisitor;
 
+use rustc_data_structures::transitive_relation::TransitiveRelation;
+
 use super::terms::*;
 use super::terms::VarianceTerm::*;
 use super::xform::*;
 
-use dep_graph::DepNode::ItemSignature as VarianceDepNode;
-
 pub struct ConstraintContext<'a, 'tcx: 'a> {
     pub terms_cx: TermsContext<'a, 'tcx>,
 
@@ -38,6 +39,11 @@ pub struct ConstraintContext<'a, 'tcx: 'a> {
     bivariant: VarianceTermPtr<'a>,
 
     pub constraints: Vec<Constraint<'a>>,
+
+    /// This relation tracks the dependencies between the variance of
+    /// various items. In particular, if `a < b`, then the variance of
+    /// `a` depends on the sources of `b`.
+    pub dependencies: TransitiveRelation<DefId>,
 }
 
 /// Declares that the variable `decl_id` appears in a location with
@@ -48,6 +54,20 @@ pub struct Constraint<'a> {
     pub variance: &'a VarianceTerm<'a>,
 }
 
+/// To build constriants, we visit one item (type, trait) at a time
+/// and look at its contents. So e.g. if we have
+///
+///     struct Foo<T> {
+///         b: Bar<T>
+///     }
+///
+/// then while we are visiting `Bar<T>`, the `CurrentItem` would have
+/// the def-id and generics of `Foo`.
+pub struct CurrentItem<'a> {
+    def_id: DefId,
+    generics: &'a ty::Generics,
+}
+
 pub fn add_constraints_from_crate<'a, 'tcx>(terms_cx: TermsContext<'a, 'tcx>)
                                             -> ConstraintContext<'a, 'tcx> {
     let tcx = terms_cx.tcx;
@@ -62,10 +82,10 @@ pub fn add_constraints_from_crate<'a, 'tcx>(terms_cx: TermsContext<'a, 'tcx>)
         invariant: invariant,
         bivariant: bivariant,
         constraints: Vec::new(),
+        dependencies: TransitiveRelation::new(),
     };
 
-    // See README.md for a discussion on dep-graph management.
+    tcx.hir.krate().visit_all_item_likes(&mut constraint_cx);
-    tcx.visit_all_item_likes_in_krate(VarianceDepNode, &mut constraint_cx);
 
     constraint_cx
 }
@@ -73,50 +93,32 @@ pub fn add_constraints_from_crate<'a, 'tcx>(terms_cx: TermsContext<'a, 'tcx>)
 impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for ConstraintContext<'a, 'tcx> {
     fn visit_item(&mut self, item: &hir::Item) {
         let tcx = self.terms_cx.tcx;
-        let did = tcx.hir.local_def_id(item.id);
+        let def_id = tcx.hir.local_def_id(item.id);
-
-        debug!("visit_item item={}", tcx.hir.node_to_string(item.id));
 
+        // Encapsulate constructing the constraints into a task we can
+        // reference later. This can go away once the red-green
+        // algorithm is in place.
+        //
+        // See README.md for a detailed discussion
+        // on dep-graph management.
         match item.node {
             hir::ItemEnum(..) |
             hir::ItemStruct(..) |
             hir::ItemUnion(..) => {
-                let generics = tcx.generics_of(did);
+                tcx.dep_graph.with_task(DepNode::ItemVarianceConstraints(def_id),
-
+                                        AssertDepGraphSafe(self),
-                // Not entirely obvious: constraints on structs/enums do not
+                                        def_id,
-                // affect the variance of their type parameters. See discussion
+                                        visit_item_task);
-                // in comment at top of module.
-                //
-                // self.add_constraints_from_generics(generics);
-
-                for field in tcx.adt_def(did).all_fields() {
-                    self.add_constraints_from_ty(generics,
-                                                 tcx.type_of(field.did),
-                                                 self.covariant);
-                }
             }
-            hir::ItemTrait(..) => {
+            _ => {
-                let generics = tcx.generics_of(did);
+                // Nothing to do here, skip the task.
-                let trait_ref = ty::TraitRef {
-                    def_id: did,
-                    substs: Substs::identity_for_item(tcx, did)
-                };
-                self.add_constraints_from_trait_ref(generics,
-                                                    trait_ref,
-                                                    self.invariant);
             }
+        }
 
-            hir::ItemExternCrate(_) |
+        fn visit_item_task<'a, 'tcx>(ccx: AssertDepGraphSafe<&mut ConstraintContext<'a, 'tcx>>,
-            hir::ItemUse(..) |
+                                     def_id: DefId)
-            hir::ItemStatic(..) |
+        {
-            hir::ItemConst(..) |
+            ccx.0.build_constraints_for_item(def_id);
-            hir::ItemFn(..) |
-            hir::ItemMod(..) |
-            hir::ItemForeignMod(..) |
-            hir::ItemGlobalAsm(..) |
-            hir::ItemTy(..) |
-            hir::ItemImpl(..) |
-            hir::ItemDefaultImpl(..) => {}
         }
     }
 
@@ -140,16 +142,64 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
         self.terms_cx.tcx
     }
 
-    fn inferred_index(&self, param_id: ast::NodeId) -> InferredIndex {
+    fn build_constraints_for_item(&mut self, def_id: DefId) {
-        match self.terms_cx.inferred_map.get(&param_id) {
+        let tcx = self.tcx();
-            Some(&index) => index,
+        let id = self.tcx().hir.as_local_node_id(def_id).unwrap();
-            None => {
+        let item = tcx.hir.expect_item(id);
-                bug!("no inferred index entry for {}",
+        debug!("visit_item item={}", tcx.hir.node_to_string(item.id));
-                     self.tcx().hir.node_to_string(param_id));
+
+        match item.node {
+            hir::ItemEnum(..) |
+            hir::ItemStruct(..) |
+            hir::ItemUnion(..) => {
+                let generics = tcx.generics_of(def_id);
+                let current_item = &CurrentItem { def_id, generics };
+
+                // Not entirely obvious: constraints on structs/enums do not
+                // affect the variance of their type parameters. See discussion
+                // in comment at top of module.
+                //
+                // self.add_constraints_from_generics(generics);
+
+                for field in tcx.adt_def(def_id).all_fields() {
+                    self.add_constraints_from_ty(current_item,
+                                                 tcx.type_of(field.did),
+                                                 self.covariant);
+                }
+            }
+
+            hir::ItemTrait(..) |
+            hir::ItemExternCrate(_) |
+            hir::ItemUse(..) |
+            hir::ItemStatic(..) |
+            hir::ItemConst(..) |
+            hir::ItemFn(..) |
+            hir::ItemMod(..) |
+            hir::ItemForeignMod(..) |
+            hir::ItemGlobalAsm(..) |
+            hir::ItemTy(..) |
+            hir::ItemImpl(..) |
+            hir::ItemDefaultImpl(..) => {
+                span_bug!(item.span, "`build_constraints_for_item` invoked for non-type-def");
             }
         }
     }
 
+    /// Load the generics for another item, adding a corresponding
+    /// relation into the dependencies to indicate that the variance
+    /// for `current` relies on `def_id`.
+    fn read_generics(&mut self, current: &CurrentItem, def_id: DefId) -> &'tcx ty::Generics {
+        let generics = self.tcx().generics_of(def_id);
+        if self.tcx().dep_graph.is_fully_enabled() {
+            self.dependencies.add(current.def_id, def_id);
+        }
+        generics
+    }
+
+    fn opt_inferred_index(&self, param_id: ast::NodeId) -> Option<&InferredIndex> {
+        self.terms_cx.inferred_map.get(&param_id)
+    }
+
     fn find_binding_for_lifetime(&self, param_id: ast::NodeId) -> ast::NodeId {
         let tcx = self.terms_cx.tcx;
         assert!(is_lifetime(&tcx.hir, param_id));
@@ -228,8 +278,27 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
             // Parameter on an item defined within current crate:
             // variance not yet inferred, so return a symbolic
             // variance.
-            let InferredIndex(index) = self.inferred_index(param_node_id);
+            if let Some(&InferredIndex(index)) = self.opt_inferred_index(param_node_id) {
-            self.terms_cx.inferred_infos[index].term
+                self.terms_cx.inferred_infos[index].term
+            } else {
+                // If there is no inferred entry for a type parameter,
+                // it must be declared on a (locally defiend) trait -- they don't
+                // get inferreds because they are always invariant.
+                if cfg!(debug_assertions) {
+                    let item_node_id = self.tcx().hir.as_local_node_id(item_def_id).unwrap();
+                    let item = self.tcx().hir.expect_item(item_node_id);
+                    let success = match item.node {
+                        hir::ItemTrait(..) => true,
+                        _ => false,
+                    };
+                    if !success {
+                        bug!("parameter {:?} has no inferred, but declared on non-trait: {:?}",
+                             item_def_id,
+                             item);
+                    }
+                }
+                self.invariant
+            }
         } else {
             // Parameter on an item defined within another crate:
             // variance already inferred, just look it up.
@@ -279,7 +348,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
     }
 
     fn add_constraints_from_trait_ref(&mut self,
-                                      generics: &ty::Generics,
+                                      current: &CurrentItem,
                                       trait_ref: ty::TraitRef<'tcx>,
                                       variance: VarianceTermPtr<'a>) {
         debug!("add_constraints_from_trait_ref: trait_ref={:?} variance={:?}",
@@ -288,12 +357,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
 
         let trait_generics = self.tcx().generics_of(trait_ref.def_id);
 
-        // This edge is actually implied by the call to
+        self.add_constraints_from_substs(current,
-        // `trait_def`, but I'm trying to be future-proof. See
-        // README.md for a discussion on dep-graph management.
-        self.tcx().dep_graph.read(VarianceDepNode(trait_ref.def_id));
-
-        self.add_constraints_from_substs(generics,
                                          trait_ref.def_id,
                                          &trait_generics.types,
                                          &trait_generics.regions,
@@ -305,7 +369,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
     /// in a context with the generics defined in `generics` and
     /// ambient variance `variance`
     fn add_constraints_from_ty(&mut self,
-                               generics: &ty::Generics,
+                               current: &CurrentItem,
                                ty: Ty<'tcx>,
                                variance: VarianceTermPtr<'a>) {
         debug!("add_constraints_from_ty(ty={:?}, variance={:?})",
@@ -325,34 +389,29 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
 
             ty::TyRef(region, ref mt) => {
                 let contra = self.contravariant(variance);
-                self.add_constraints_from_region(generics, region, contra);
+                self.add_constraints_from_region(current, region, contra);
-                self.add_constraints_from_mt(generics, mt, variance);
+                self.add_constraints_from_mt(current, mt, variance);
             }
 
             ty::TyArray(typ, _) |
             ty::TySlice(typ) => {
-                self.add_constraints_from_ty(generics, typ, variance);
+                self.add_constraints_from_ty(current, typ, variance);
             }
 
             ty::TyRawPtr(ref mt) => {
-                self.add_constraints_from_mt(generics, mt, variance);
+                self.add_constraints_from_mt(current, mt, variance);
             }
 
             ty::TyTuple(subtys, _) => {
                 for &subty in subtys {
-                    self.add_constraints_from_ty(generics, subty, variance);
+                    self.add_constraints_from_ty(current, subty, variance);
                 }
             }
 
             ty::TyAdt(def, substs) => {
-                let adt_generics = self.tcx().generics_of(def.did);
+                let adt_generics = self.read_generics(current, def.did);
 
-                // This edge is actually implied by the call to
+                self.add_constraints_from_substs(current,
-                // `trait_def`, but I'm trying to be future-proof. See
-                // README.md for a discussion on dep-graph management.
-                self.tcx().dep_graph.read(VarianceDepNode(def.did));
-
-                self.add_constraints_from_substs(generics,
                                                  def.did,
                                                  &adt_generics.types,
                                                  &adt_generics.regions,
@@ -364,12 +423,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
                 let trait_ref = &data.trait_ref;
                 let trait_generics = self.tcx().generics_of(trait_ref.def_id);
 
-                // This edge is actually implied by the call to
+                self.add_constraints_from_substs(current,
-                // `trait_def`, but I'm trying to be future-proof. See
-                // README.md for a discussion on dep-graph management.
-                self.tcx().dep_graph.read(VarianceDepNode(trait_ref.def_id));
-
-                self.add_constraints_from_substs(generics,
                                                  trait_ref.def_id,
                                                  &trait_generics.types,
                                                  &trait_generics.regions,
@@ -380,25 +434,25 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
             ty::TyDynamic(ref data, r) => {
                 // The type `Foo<T+'a>` is contravariant w/r/t `'a`:
                 let contra = self.contravariant(variance);
-                self.add_constraints_from_region(generics, r, contra);
+                self.add_constraints_from_region(current, r, contra);
 
                 if let Some(p) = data.principal() {
                     let poly_trait_ref = p.with_self_ty(self.tcx(), self.tcx().types.err);
-                    self.add_constraints_from_trait_ref(generics, poly_trait_ref.0, variance);
+                    self.add_constraints_from_trait_ref(current, poly_trait_ref.0, variance);
                 }
 
                 for projection in data.projection_bounds() {
-                    self.add_constraints_from_ty(generics, projection.0.ty, self.invariant);
+                    self.add_constraints_from_ty(current, projection.0.ty, self.invariant);
                 }
             }
 
             ty::TyParam(ref data) => {
-                assert_eq!(generics.parent, None);
+                assert_eq!(current.generics.parent, None);
                 let mut i = data.idx as usize;
-                if !generics.has_self || i > 0 {
+                if !current.generics.has_self || i > 0 {
-                    i -= generics.regions.len();
+                    i -= current.generics.regions.len();
                 }
-                let def_id = generics.types[i].def_id;
+                let def_id = current.generics.types[i].def_id;
                 let node_id = self.tcx().hir.as_local_node_id(def_id).unwrap();
                 match self.terms_cx.inferred_map.get(&node_id) {
                     Some(&index) => {
@@ -414,7 +468,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
 
             ty::TyFnDef(.., sig) |
             ty::TyFnPtr(sig) => {
-                self.add_constraints_from_sig(generics, sig, variance);
+                self.add_constraints_from_sig(current, sig, variance);
             }
 
             ty::TyError => {
@@ -433,7 +487,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
     /// Adds constraints appropriate for a nominal type (enum, struct,
     /// object, etc) appearing in a context with ambient variance `variance`
     fn add_constraints_from_substs(&mut self,
-                                   generics: &ty::Generics,
+                                   current: &CurrentItem,
                                    def_id: DefId,
                                    type_param_defs: &[ty::TypeParameterDef],
                                    region_param_defs: &[ty::RegionParameterDef],
@@ -451,44 +505,44 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
             debug!("add_constraints_from_substs: variance_decl={:?} variance_i={:?}",
                    variance_decl,
                    variance_i);
-            self.add_constraints_from_ty(generics, substs_ty, variance_i);
+            self.add_constraints_from_ty(current, substs_ty, variance_i);
         }
 
         for p in region_param_defs {
             let variance_decl = self.declared_variance(p.def_id, def_id, p.index as usize);
             let variance_i = self.xform(variance, variance_decl);
             let substs_r = substs.region_for_def(p);
-            self.add_constraints_from_region(generics, substs_r, variance_i);
+            self.add_constraints_from_region(current, substs_r, variance_i);
         }
     }
 
     /// Adds constraints appropriate for a function with signature
     /// `sig` appearing in a context with ambient variance `variance`
     fn add_constraints_from_sig(&mut self,
-                                generics: &ty::Generics,
+                                current: &CurrentItem,
                                 sig: ty::PolyFnSig<'tcx>,
                                 variance: VarianceTermPtr<'a>) {
         let contra = self.contravariant(variance);
         for &input in sig.0.inputs() {
-            self.add_constraints_from_ty(generics, input, contra);
+            self.add_constraints_from_ty(current, input, contra);
         }
-        self.add_constraints_from_ty(generics, sig.0.output(), variance);
+        self.add_constraints_from_ty(current, sig.0.output(), variance);
     }
 
     /// Adds constraints appropriate for a region appearing in a
     /// context with ambient variance `variance`
     fn add_constraints_from_region(&mut self,
-                                   generics: &ty::Generics,
+                                   current: &CurrentItem,
                                    region: ty::Region<'tcx>,
                                    variance: VarianceTermPtr<'a>) {
         match *region {
             ty::ReEarlyBound(ref data) => {
-                assert_eq!(generics.parent, None);
+                assert_eq!(current.generics.parent, None);
-                let i = data.index as usize - generics.has_self as usize;
+                let i = data.index as usize - current.generics.has_self as usize;
-                let def_id = generics.regions[i].def_id;
+                let def_id = current.generics.regions[i].def_id;
                 let node_id = self.tcx().hir.as_local_node_id(def_id).unwrap();
                 if self.is_to_be_inferred(node_id) {
-                    let index = self.inferred_index(node_id);
+                    let &index = self.opt_inferred_index(node_id).unwrap();
                     self.add_constraint(index, variance);
                 }
             }
@@ -518,17 +572,17 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
     /// Adds constraints appropriate for a mutability-type pair
     /// appearing in a context with ambient variance `variance`
     fn add_constraints_from_mt(&mut self,
-                               generics: &ty::Generics,
+                               current: &CurrentItem,
                                mt: &ty::TypeAndMut<'tcx>,
                                variance: VarianceTermPtr<'a>) {
         match mt.mutbl {
             hir::MutMutable => {
                 let invar = self.invariant(variance);
-                self.add_constraints_from_ty(generics, mt.ty, invar);
+                self.add_constraints_from_ty(current, mt.ty, invar);
             }
 
             hir::MutImmutable => {
-                self.add_constraints_from_ty(generics, mt.ty, variance);
+                self.add_constraints_from_ty(current, mt.ty, variance);
             }
         }
     }

src/librustc_typeck/variance/mod.rs

@@ -12,7 +12,12 @@
 //! parameters. See README.md for details.
 
 use arena;
-use rustc::ty::TyCtxt;
+use rustc::dep_graph::DepNode;
+use rustc::hir;
+use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
+use rustc::ty::{self, CrateVariancesMap, TyCtxt};
+use rustc::ty::maps::Providers;
+use std::rc::Rc;
 
 /// Defines the `TermsContext` basically houses an arena where we can
 /// allocate terms.
@@ -24,13 +29,67 @@ mod constraints;
 /// Code to solve constraints and write out the results.
 mod solve;
 
+/// Code to write unit tests of variance.
+pub mod test;
+
 /// Code for transforming variances.
 mod xform;
 
-pub fn infer_variance<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
+pub fn provide(providers: &mut Providers) {
+    *providers = Providers {
+        variances_of,
+        crate_variances,
+        ..*providers
+    };
+}
+
+fn crate_variances<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, crate_num: CrateNum)
+                             -> Rc<CrateVariancesMap> {
+    assert_eq!(crate_num, LOCAL_CRATE);
     let mut arena = arena::TypedArena::new();
     let terms_cx = terms::determine_parameters_to_be_inferred(tcx, &mut arena);
     let constraints_cx = constraints::add_constraints_from_crate(terms_cx);
-    solve::solve_constraints(constraints_cx);
+    Rc::new(solve::solve_constraints(constraints_cx))
-    tcx.variance_computed.set(true);
 }
+
+fn variances_of<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, item_def_id: DefId)
+                            -> Rc<Vec<ty::Variance>> {
+    let item_id = tcx.hir.as_local_node_id(item_def_id).expect("expected local def-id");
+    let item = tcx.hir.expect_item(item_id);
+    match item.node {
+        hir::ItemTrait(..) => {
+            // Traits are always invariant.
+            let generics = tcx.generics_of(item_def_id);
+            assert!(generics.parent.is_none());
+            Rc::new(vec![ty::Variance::Invariant; generics.count()])
+        }
+
+        hir::ItemEnum(..) |
+        hir::ItemStruct(..) |
+        hir::ItemUnion(..) => {
+            // Everything else must be inferred.
+
+            // Lacking red/green, we read the variances for all items here
+            // but ignore the dependencies, then re-synthesize the ones we need.
+            let crate_map = tcx.dep_graph.with_ignore(|| tcx.crate_variances(LOCAL_CRATE));
+            tcx.dep_graph.read(DepNode::ItemVarianceConstraints(item_def_id));
+            for &dep_def_id in crate_map.dependencies.less_than(&item_def_id) {
+                if dep_def_id.is_local() {
+                    tcx.dep_graph.read(DepNode::ItemVarianceConstraints(dep_def_id));
+                } else {
+                    tcx.dep_graph.read(DepNode::ItemVariances(dep_def_id));
+                }
+            }
+
+            crate_map.variances.get(&item_def_id)
+                               .unwrap_or(&crate_map.empty_variance)
+                               .clone()
+        }
+
+        _ => {
+            // Variance not relevant.
+            span_bug!(item.span, "asked to compute variance for wrong kind of item")
+        }
+    }
+}
+

src/librustc_typeck/variance/solve.rs

@@ -15,7 +15,9 @@
 //! optimal solution to the constraints. The final variance for each
 //! inferred is then written into the `variance_map` in the tcx.
 
+use rustc::hir::def_id::DefId;
 use rustc::ty;
+use rustc_data_structures::fx::FxHashMap;
 use std::rc::Rc;
 
 use super::constraints::*;
@@ -31,8 +33,8 @@ struct SolveContext<'a, 'tcx: 'a> {
     solutions: Vec<ty::Variance>,
 }
 
-pub fn solve_constraints(constraints_cx: ConstraintContext) {
+pub fn solve_constraints(constraints_cx: ConstraintContext) -> ty::CrateVariancesMap {
-    let ConstraintContext { terms_cx, constraints, .. } = constraints_cx;
+    let ConstraintContext { terms_cx, dependencies, constraints, .. } = constraints_cx;
 
     let solutions = terms_cx.inferred_infos
         .iter()
@@ -45,7 +47,10 @@ pub fn solve_constraints(constraints_cx: ConstraintContext) {
         solutions: solutions,
     };
     solutions_cx.solve();
-    solutions_cx.write();
+    let variances = solutions_cx.create_map();
+    let empty_variance = Rc::new(Vec::new());
+
+    ty::CrateVariancesMap { dependencies, variances, empty_variance }
 }
 
 impl<'a, 'tcx> SolveContext<'a, 'tcx> {
@@ -83,7 +88,7 @@ impl<'a, 'tcx> SolveContext<'a, 'tcx> {
         }
     }
 
-    fn write(&self) {
+    fn create_map(&self) -> FxHashMap<DefId, Rc<Vec<ty::Variance>>> {
         // Collect all the variances for a particular item and stick
         // them into the variance map. We rely on the fact that we
         // generate all the inferreds for a particular item
@@ -95,11 +100,7 @@ impl<'a, 'tcx> SolveContext<'a, 'tcx> {
 
         let tcx = self.terms_cx.tcx;
 
-        // Ignore the writes here because the relevant edges were
+        let mut map = FxHashMap();
-        // already accounted for in `constraints.rs`. See the section
-        // on dependency graph management in README.md for more
-        // information.
-        let _ignore = tcx.dep_graph.in_ignore();
 
         let solutions = &self.solutions;
         let inferred_infos = &self.terms_cx.inferred_infos;
@@ -127,19 +128,10 @@ impl<'a, 'tcx> SolveContext<'a, 'tcx> {
 
             let item_def_id = tcx.hir.local_def_id(item_id);
 
-            // For unit testing: check for a special "rustc_variance"
+            map.insert(item_def_id, Rc::new(item_variances));
-            // attribute and report an error with various results if found.
-            if tcx.has_attr(item_def_id, "rustc_variance") {
-                span_err!(tcx.sess,
-                          tcx.hir.span(item_id),
-                          E0208,
-                          "{:?}",
-                          item_variances);
-            }
-
-            tcx.maps.variances_of.borrow_mut()
-               .insert(item_def_id, Rc::new(item_variances));
         }
+
+        map
     }
 
     fn evaluate(&self, term: VarianceTermPtr<'a>) -> ty::Variance {

src/librustc_typeck/variance/terms.rs

@@ -32,8 +32,6 @@ use self::VarianceTerm::*;
 
 pub type VarianceTermPtr<'a> = &'a VarianceTerm<'a>;
 
-use dep_graph::DepNode::ItemSignature as VarianceDepNode;
-
 #[derive(Copy, Clone, Debug)]
 pub struct InferredIndex(pub usize);
 
@@ -109,7 +107,7 @@ pub fn determine_parameters_to_be_inferred<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>
     };
 
     // See README.md for a discussion on dep-graph management.
-    tcx.visit_all_item_likes_in_krate(|def_id| VarianceDepNode(def_id), &mut terms_cx);
+    tcx.hir.krate().visit_all_item_likes(&mut terms_cx);
 
     terms_cx
 }
@@ -139,7 +137,6 @@ fn lang_items(tcx: TyCtxt) -> Vec<(ast::NodeId, Vec<ty::Variance>)> {
 impl<'a, 'tcx> TermsContext<'a, 'tcx> {
     fn add_inferreds_for_item(&mut self,
                               item_id: ast::NodeId,
-                              has_self: bool,
                               generics: &hir::Generics) {
         //! Add "inferreds" for the generic parameters declared on this
         //! item. This has a lot of annoying parameters because we are
@@ -149,38 +146,17 @@ impl<'a, 'tcx> TermsContext<'a, 'tcx> {
         //!
 
         // NB: In the code below for writing the results back into the
-        // tcx, we rely on the fact that all inferreds for a particular
+        // `CrateVariancesMap`, we rely on the fact that all inferreds
-        // item are assigned continuous indices.
+        // for a particular item are assigned continuous indices.
 
-        let inferreds_on_entry = self.num_inferred();
+        for (p, i) in generics.lifetimes.iter().zip(0..) {
-
-        if has_self {
-            self.add_inferred(item_id, 0, item_id);
-        }
-
-        for (i, p) in generics.lifetimes.iter().enumerate() {
             let id = p.lifetime.id;
-            let i = has_self as usize + i;
             self.add_inferred(item_id, i, id);
         }
 
-        for (i, p) in generics.ty_params.iter().enumerate() {
+        for (p, i) in generics.ty_params.iter().zip(generics.lifetimes.len()..) {
-            let i = has_self as usize + generics.lifetimes.len() + i;
             self.add_inferred(item_id, i, p.id);
         }
-
-        // If this item has no type or lifetime parameters,
-        // then there are no variances to infer, so just
-        // insert an empty entry into the variance map.
-        // Arguably we could just leave the map empty in this
-        // case but it seems cleaner to be able to distinguish
-        // "invalid item id" from "item id with no
-        // parameters".
-        if self.num_inferred() == inferreds_on_entry {
-            let item_def_id = self.tcx.hir.local_def_id(item_id);
-            self.tcx.maps.variances_of.borrow_mut()
-                .insert(item_def_id, self.empty_variances.clone());
-        }
     }
 
     fn add_inferred(&mut self, item_id: ast::NodeId, index: usize, param_id: ast::NodeId) {
@@ -232,15 +208,10 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for TermsContext<'a, 'tcx> {
             hir::ItemEnum(_, ref generics) |
             hir::ItemStruct(_, ref generics) |
             hir::ItemUnion(_, ref generics) => {
-                self.add_inferreds_for_item(item.id, false, generics);
+                self.add_inferreds_for_item(item.id, generics);
-            }
-            hir::ItemTrait(_, ref generics, ..) => {
-                // Note: all inputs for traits are ultimately
-                // constrained to be invariant. See `visit_item` in
-                // the impl for `ConstraintContext` in `constraints.rs`.
-                self.add_inferreds_for_item(item.id, true, generics);
             }
 
+            hir::ItemTrait(..) |
             hir::ItemExternCrate(_) |
             hir::ItemUse(..) |
             hir::ItemDefaultImpl(..) |

src/librustc_typeck/variance/test.rs

@@ -0,0 +1,41 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use rustc::hir;
+use rustc::hir::itemlikevisit::ItemLikeVisitor;
+use rustc::ty::TyCtxt;
+
+pub fn test_variance<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) {
+    tcx.hir.krate().visit_all_item_likes(&mut VarianceTest { tcx });
+}
+
+struct VarianceTest<'a, 'tcx: 'a> {
+    tcx: TyCtxt<'a, 'tcx, 'tcx>
+}
+
+impl<'a, 'tcx> ItemLikeVisitor<'tcx> for VarianceTest<'a, 'tcx> {
+    fn visit_item(&mut self, item: &'tcx hir::Item) {
+        let item_def_id = self.tcx.hir.local_def_id(item.id);
+
+        // For unit testing: check for a special "rustc_variance"
+        // attribute and report an error with various results if found.
+        if self.tcx.has_attr(item_def_id, "rustc_variance") {
+            let variances_of = self.tcx.variances_of(item_def_id);
+            span_err!(self.tcx.sess,
+                      item.span,
+                      E0208,
+                      "{:?}",
+                      variances_of);
+        }
+    }
+
+    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem) { }
+    fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) { }
+}

src/librustdoc/core.rs

@@ -104,7 +104,8 @@ pub fn run_core(search_paths: SearchPaths,
                 externs: config::Externs,
                 input: Input,
                 triple: Option<String>,
-                maybe_sysroot: Option<PathBuf>) -> (clean::Crate, RenderInfo)
+                maybe_sysroot: Option<PathBuf>,
+                allow_warnings: bool) -> (clean::Crate, RenderInfo)
 {
     // Parse, resolve, and typecheck the given crate.
 
@@ -119,7 +120,7 @@ pub fn run_core(search_paths: SearchPaths,
         maybe_sysroot: maybe_sysroot,
         search_paths: search_paths,
         crate_types: vec![config::CrateTypeRlib],
-        lint_opts: vec![(warning_lint, lint::Allow)],
+        lint_opts: if !allow_warnings { vec![(warning_lint, lint::Allow)] } else { vec![] },
         lint_cap: Some(lint::Allow),
         externs: externs,
         target_triple: triple.unwrap_or(config::host_triple().to_string()),

src/librustdoc/html/layout.rs

@@ -137,7 +137,6 @@ r##"<!DOCTYPE html>
         window.rootPath = "{root_path}";
         window.currentCrate = "{krate}";
     </script>
-    <script src="{root_path}jquery.js"></script>
     <script src="{root_path}main.js"></script>
     <script defer src="{root_path}search-index.js"></script>
 </body>

src/librustdoc/html/render.rs

@@ -660,8 +660,6 @@ fn write_shared(cx: &Context,
     // Add all the static files. These may already exist, but we just
     // overwrite them anyway to make sure that they're fresh and up-to-date.
 
-    write(cx.dst.join("jquery.js"),
-          include_bytes!("static/jquery-2.1.4.min.js"))?;
     write(cx.dst.join("main.js"),
           include_bytes!("static/main.js"))?;
     write(cx.dst.join("rustdoc.css"),

src/librustdoc/html/static/COPYRIGHT.txt

@@ -27,11 +27,6 @@ included, and carry their own copyright notices and license terms:
     Licensed under the SIL Open Font License, Version 1.1.
     See Heuristica-LICENSE.txt.
 
-* jQuery (jquery-2.1.4.min.js):
-
-    Copyright 2005, 2015 jQuery Foundation, Inc.
-    Licensed under the MIT license (see LICENSE-MIT.txt).
-
 * rustdoc.css, main.js, and playpen.js:
 
     Copyright 2015 The Rust Developers.

src/librustdoc/html/static/main.js

@@ -37,10 +37,63 @@
                      "associatedconstant",
                      "union"];
 
+    function hasClass(elem, className) {
+        if (elem && className && elem.className) {
+            var elemClass = elem.className;
+            var start = elemClass.indexOf(className);
+            if (start == -1) {
+                return false;
+            } else if (elemClass.length == className.length) {
+                return true;
+            } else {
+                if (start > 0 && elemClass[start - 1] != ' ') {
+                    return false;
+                }
+                var end = start + className.length;
+                if (end < elemClass.length && elemClass[end] != ' ') {
+                    return false;
+                }
+                return true;
+            }
+        }
+        return false;
+    }
+
+    function addClass(elem, className) {
+        if (elem && className && !hasClass(elem, className)) {
+            if (elem.className && elem.className.length > 0) {
+                elem.className += ' ' + className;
+            } else {
+                elem.className = className;
+            }
+        }
+    }
+
+    function removeClass(elem, className) {
+        if (elem && className && elem.className) {
+            elem.className = (" " + elem.className + " ").replace(" " + className + " ", " ")
+                                                         .trim();
+        }
+    }
+
+    function onEach(arr, func) {
+        if (arr && arr.length > 0 && func) {
+            for (var i = 0; i < arr.length; i++) {
+                func(arr[i]);
+            }
+        }
+    }
+
+    function isHidden(elem) {
+        return (elem.offsetParent === null)
+    }
+
     // used for special search precedence
     var TY_PRIMITIVE = itemTypes.indexOf("primitive");
 
-    $('.js-only').removeClass('js-only');
+    onEach(document.getElementsByClassName('js-only'), function(e) {
+        removeClass(e, 'js-only');
+    });
 
     function getQueryStringParams() {
         var params = {};
@@ -65,18 +118,28 @@
             from = parseInt(match[1], 10);
             to = Math.min(50000, parseInt(match[2] || match[1], 10));
             from = Math.min(from, to);
-            if ($('#' + from).length === 0) {
+            var elem = document.getElementById(from);
+            if (!elem) {
                 return;
             }
-            if (ev === null) { $('#' + from)[0].scrollIntoView(); };
+            if (ev === null) {
-            $('.line-numbers span').removeClass('line-highlighted');
+                var x = document.getElementById(from);
+                if (x) {
+                    x.scrollIntoView();
+                }
+            };
+            onEach(document.getElementsByClassName('line-numbers'), function(e) {
+                onEach(e.getElementsByTagName('span'), function(i_e) {
+                    removeClass(i_e, 'line-highlighted');
+                });
+            })
             for (i = from; i <= to; ++i) {
-                $('#' + i).addClass('line-highlighted');
+                addClass(document.getElementById(i), 'line-highlighted');
             }
         }
     }
     highlightSourceLines(null);
-    $(window).on('hashchange', highlightSourceLines);
+    window.onhashchange = highlightSourceLines;
 
     // Gets the human-readable string for the virtual-key code of the
     // given KeyboardEvent, ev.
@@ -99,23 +162,25 @@
     }
 
     function handleShortcut(ev) {
-        if (document.activeElement.tagName == "INPUT")
+        if (document.activeElement.tagName === "INPUT")
             return;
 
         // Don't interfere with browser shortcuts
         if (ev.ctrlKey || ev.altKey || ev.metaKey)
             return;
 
+        var help = document.getElementById("help");
         switch (getVirtualKey(ev)) {
         case "Escape":
-            if (!$("#help").hasClass("hidden")) {
+            var search = document.getElementById("search");
+            if (!hasClass(help, "hidden")) {
                 ev.preventDefault();
-                $("#help").addClass("hidden");
+                addClass(help, "hidden");
-                $("body").removeClass("blur");
+                removeClass(document.body, "blur");
-            } else if (!$("#search").hasClass("hidden")) {
+            } else if (!hasClass(search, "hidden")) {
                 ev.preventDefault();
-                $("#search").addClass("hidden");
+                addClass(search, "hidden");
-                $("#main").removeClass("hidden");
+                removeClass(document.getElementById("main"), "hidden");
             }
             break;
 
@@ -131,42 +196,76 @@
             break;
 
         case "?":
-            if (ev.shiftKey && $("#help").hasClass("hidden")) {
+            if (ev.shiftKey && hasClass(help, "hidden")) {
                 ev.preventDefault();
-                $("#help").removeClass("hidden");
+                removeClass(help, "hidden");
-                $("body").addClass("blur");
+                addClass(document.body, "blur");
             }
             break;
         }
     }
 
-    $(document).on("keypress", handleShortcut);
+    document.onkeypress = handleShortcut;
-    $(document).on("keydown", handleShortcut);
+    document.onkeydown = handleShortcut;
-    $(document).on("click", function(ev) {
+    document.onclick = function(ev) {
-        if (!$(ev.target).closest("#help > div").length) {
+        if (hasClass(ev.target, 'collapse-toggle')) {
-            $("#help").addClass("hidden");
+            collapseDocs(ev.target);
-            $("body").removeClass("blur");
+        } else if (hasClass(ev.target.parentNode, 'collapse-toggle')) {
-        }
+            collapseDocs(ev.target.parentNode);
-    });
+        } else if (ev.target.tagName === 'SPAN' && hasClass(ev.target.parentNode, 'line-numbers')) {
+            var prev_id = 0;
 
-    $('.version-selector').on('change', function() {
+            function set_fragment(name) {
-        var i, match,
+                if (browserSupportsHistoryApi()) {
-            url = document.location.href,
+                    history.replaceState(null, null, '#' + name);
-            stripped = '',
+                    window.hashchange();
-            len = rootPath.match(/\.\.\//g).length + 1;
+                } else {
-
+                    location.replace('#' + name);
-        for (i = 0; i < len; ++i) {
+                }
-            match = url.match(/\/[^\/]*$/);
-            if (i < len - 1) {
-                stripped = match[0] + stripped;
             }
-            url = url.substring(0, url.length - match[0].length);
+
+            var cur_id = parseInt(ev.target.id, 10);
+
+            if (ev.shiftKey && prev_id) {
+                if (prev_id > cur_id) {
+                    var tmp = prev_id;
+                    prev_id = cur_id;
+                    cur_id = tmp;
+                }
+
+                set_fragment(prev_id + '-' + cur_id);
+            } else {
+                prev_id = cur_id;
+
+                set_fragment(cur_id);
+            }
+        } else if (!hasClass(document.getElementById("help"), "hidden")) {
+            addClass(document.getElementById("help"), "hidden");
+            removeClass(document.body, "blur");
         }
+    };
 
-        url += '/' + $('.version-selector').val() + stripped;
+    var x = document.getElementsByClassName('version-selector');
+    if (x.length > 0) {
+        x[0].onchange = function() {
+            var i, match,
+                url = document.location.href,
+                stripped = '',
+                len = rootPath.match(/\.\.\//g).length + 1;
 
-        document.location.href = url;
+            for (i = 0; i < len; ++i) {
-    });
+                match = url.match(/\/[^\/]*$/);
+                if (i < len - 1) {
+                    stripped = match[0] + stripped;
+                }
+                url = url.substring(0, url.length - match[0].length);
+            }
+
+            url += '/' + document.getElementsByClassName('version-selector')[0].value + stripped;
+
+            document.location.href = url;
+        };
+    }
 
     /**
      * A function to compute the Levenshtein distance between two strings
@@ -214,8 +313,8 @@
         // but only if the input bar is empty. This avoid the obnoxious issue
         // where you start trying to do a search, and the index loads, and
         // suddenly your search is gone!
-        if ($(".search-input")[0].value === "") {
+        if (document.getElementsByClassName("search-input")[0].value === "") {
-            $(".search-input")[0].value = params.search || '';
+            document.getElementsByClassName("search-input")[0].value = params.search || '';
         }
 
         /**
@@ -484,7 +583,8 @@
         }
 
         function getQuery() {
-            var matches, type, query, raw = $('.search-input').val();
+            var matches, type, query, raw =
+                document.getElementsByClassName('search-input')[0].value;
             query = raw;
 
             matches = query.match(/^(fn|mod|struct|enum|trait|type|const|macro)\s*:\s*/i);
@@ -502,54 +602,92 @@
         }
 
         function initSearchNav() {
-            var hoverTimeout, $results = $('.search-results .result');
+            var hoverTimeout;
 
-            $results.on('click', function() {
+            var click_func = function(e) {
-                var dst = $(this).find('a')[0];
+                var el = e.target;
+                // to retrieve the real "owner" of the event.
+                while (el.tagName !== 'TR') {
+                    el = el.parentNode;
+                }
+                var dst = e.target.getElementsByTagName('a');
+                if (dst.length < 1) {
+                    return;
+                }
+                dst = dst[0];
                 if (window.location.pathname === dst.pathname) {
-                    $('#search').addClass('hidden');
+                    addClass(document.getElementById('search'), 'hidden');
-                    $('#main').removeClass('hidden');
+                    removeClass(document.getElementById('main'), 'hidden');
                     document.location.href = dst.href;
                 }
-            }).on('mouseover', function() {
+            };
-                var $el = $(this);
+            var mouseover_func = function(e) {
+                var el = e.target;
+                // to retrieve the real "owner" of the event.
+                while (el.tagName !== 'TR') {
+                    el = el.parentNode;
+                }
                 clearTimeout(hoverTimeout);
                 hoverTimeout = setTimeout(function() {
-                    $results.removeClass('highlighted');
+                    onEach(document.getElementsByClassName('search-results'), function(e) {
-                    $el.addClass('highlighted');
+                        onEach(e.getElementsByClassName('result'), function(i_e) {
+                            removeClass(i_e, 'highlighted');
+                        });
+                    });
+                    addClass(el, 'highlighted');
                 }, 20);
+            };
+            onEach(document.getElementsByClassName('search-results'), function(e) {
+                onEach(e.getElementsByClassName('result'), function(i_e) {
+                    i_e.onclick = click_func;
+                    i_e.onmouseover = mouseover_func;
+                });
             });
 
-            $(document).off('keydown.searchnav');
+            var search_input = document.getElementsByClassName('search-input')[0];
-            $(document).on('keydown.searchnav', function(e) {
+            search_input.onkeydown = null;
-                var $active = $results.filter('.highlighted');
+            search_input.onkeydown = function(e) {
+                var actives = [];
+                onEach(document.getElementsByClassName('search-results'), function(e) {
+                    onEach(document.getElementsByClassName('highlighted'), function(e) {
+                        actives.push(e);
+                    });
+                });
 
                 if (e.which === 38) { // up
-                    if (!$active.length || !$active.prev()) {
+                    if (!actives.length || !actives[0].previousElementSibling) {
                         return;
                     }
 
-                    $active.prev().addClass('highlighted');
+                    addClass(actives[0].previousElementSibling, 'highlighted');
-                    $active.removeClass('highlighted');
+                    removeClass(actives[0], 'highlighted');
                 } else if (e.which === 40) { // down
-                    if (!$active.length) {
+                    if (!actives.length) {
-                        $results.first().addClass('highlighted');
+                        var results = document.getElementsByClassName('search-results');
-                    } else if ($active.next().length) {
+                        if (results.length > 0) {
-                        $active.next().addClass('highlighted');
+                            var res = results[0].getElementsByClassName('result');
-                        $active.removeClass('highlighted');
+                            if (res.length > 0) {
+                                addClass(res[0], 'highlighted');
+                            }
+                        }
+                    } else if (actives[0].nextElementSibling) {
+                        addClass(actives[0].nextElementSibling, 'highlighted');
+                        removeClass(actives[0], 'highlighted');
                     }
                 } else if (e.which === 13) { // return
-                    if ($active.length) {
+                    if (actives.length) {
-                        document.location.href = $active.find('a').prop('href');
+                        document.location.href = actives[0].getElementsByTagName('a')[0].href;
                     }
-                } else {
+                } else if (actives.length > 0) {
-                  $active.removeClass('highlighted');
+                    removeClass(actives[0], 'highlighted');
                 }
-            });
+            };
         }
 
         function escape(content) {
-            return $('<h1/>').text(content).html();
+            let h1 = document.createElement('h1');
+            h1.textContent = content;
+            return h1.innerHTML;
         }
 
         function showResults(results) {
@@ -619,10 +757,19 @@
             }
 
             output += "</p>";
-            $('#main.content').addClass('hidden');
+            addClass(document.getElementById('main'), 'hidden');
-            $('#search.content').removeClass('hidden').html(output);
+            var search = document.getElementById('search');
-            $('#search .desc').width($('#search').width() - 40 -
+            removeClass(search, 'hidden');
-                $('#search td:first-child').first().width());
+            search.innerHTML = output;
+            var tds = search.getElementsByTagName('td');
+            var td_width = 0;
+            if (tds.length > 0) {
+                td_width = tds[0].offsetWidth;
+            }
+            var width = search.offsetWidth - 40 - td_width;
+            onEach(search.getElementsByClassName('desc'), function(e) {
+                e.style.width = width + 'px';
+            });
             initSearchNav();
         }
 
@@ -645,17 +792,15 @@
             }
 
             // Update document title to maintain a meaningful browser history
-            $(document).prop("title", "Results for " + query.query + " - Rust");
+            document.title = "Results for " + query.query + " - Rust";
 
             // Because searching is incremental by character, only the most
             // recent search query is added to the browser history.
             if (browserSupportsHistoryApi()) {
                 if (!history.state && !params.search) {
-                    history.pushState(query, "", "?search=" +
+                    history.pushState(query, "", "?search=" + encodeURIComponent(query.raw));
-                                                encodeURIComponent(query.raw));
                 } else {
-                    history.replaceState(query, "", "?search=" +
+                    history.replaceState(query, "", "?search=" + encodeURIComponent(query.raw));
-                                                encodeURIComponent(query.raw));
                 }
             }
 
@@ -744,49 +889,68 @@
 
         function startSearch() {
             var searchTimeout;
-            $(".search-input").on("keyup input",function() {
+            var callback = function() {
+                var search_input = document.getElementsByClassName('search-input');
+                if (search_input.length < 1) { return; }
+                search_input = search_input[0];
                 clearTimeout(searchTimeout);
-                if ($(this).val().length === 0) {
+                if (search_input.value.length === 0) {
                     if (browserSupportsHistoryApi()) {
                         history.replaceState("", "std - Rust", "?search=");
                     }
-                    $('#main.content').removeClass('hidden');
+                    var main = document.getElementById('main');
-                    $('#search.content').addClass('hidden');
+                    if (hasClass(main, 'content')) {
+                        removeClass(main, 'hidden');
+                    }
+                    var search_c = document.getElementById('search');
+                    if (hasClass(search_c, 'content')) {
+                        addClass(search_c, 'hidden');
+                    }
                 } else {
                     searchTimeout = setTimeout(search, 500);
                 }
-            });
+            };
-            $('.search-form').on('submit', function(e){
+            var search_input = document.getElementsByClassName("search-input")[0];
+            search_input.onkeyup = callback;
+            search_input.oninput = callback;
+            document.getElementsByClassName("search-form")[0].onsubmit = function(e){
                 e.preventDefault();
                 clearTimeout(searchTimeout);
                 search();
-            });
+            };
-            $('.search-input').on('change paste', function(e) {
+            search_input.onchange = function(e) {
                 // Do NOT e.preventDefault() here. It will prevent pasting.
                 clearTimeout(searchTimeout);
                 // zero-timeout necessary here because at the time of event handler execution the
                 // pasted content is not in the input field yet. Shouldn’t make any difference for
                 // change, though.
                 setTimeout(search, 0);
-            });
+            };
+            search_input.onpaste = search_input.onchange;
 
             // Push and pop states are used to add search results to the browser
             // history.
             if (browserSupportsHistoryApi()) {
                 // Store the previous <title> so we can revert back to it later.
-                var previousTitle = $(document).prop("title");
+                var previousTitle = document.title;
 
-                $(window).on('popstate', function(e) {
+                window.onpopstate = function(e) {
                     var params = getQueryStringParams();
                     // When browsing back from search results the main page
                     // visibility must be reset.
                     if (!params.search) {
-                        $('#main.content').removeClass('hidden');
+                        var main = document.getElementById('main');
-                        $('#search.content').addClass('hidden');
+                        if (hasClass(main, 'content')) {
+                            removeClass(main, 'hidden');
+                        }
+                        var search = document.getElementById('search');
+                        if (hasClass(main, 'content')) {
+                            addClass(main, 'hidden');
+                        }
                     }
                     // Revert to the previous title manually since the History
                     // API ignores the title parameter.
-                    $(document).prop("title", previousTitle);
+                    document.title = previousTitle;
                     // When browsing forward to search results the previous
                     // search will be repeated, so the currentResults are
                     // cleared to ensure the search is successful.
@@ -795,14 +959,14 @@
                     // perform the search. This will empty the bar if there's
                     // nothing there, which lets you really go back to a
                     // previous state with nothing in the bar.
-                    $('.search-input').val(params.search);
+                    document.getElementsByClassName('search-input')[0].value = params.search;
                     // Some browsers fire 'onpopstate' for every page load
                     // (Chrome), while others fire the event only when actually
                     // popping a state (Firefox), which is why search() is
                     // called both here and at the end of the startSearch()
                     // function.
                     search();
-                });
+                };
             }
             search();
         }
@@ -812,10 +976,12 @@
 
         // Draw a convenient sidebar of known crates if we have a listing
         if (rootPath === '../') {
-            var sidebar = $('.sidebar');
+            var sidebar = document.getElementsByClassName('sidebar')[0];
-            var div = $('<div>').attr('class', 'block crate');
+            var div = document.createElement('div');
-            div.append($('<h3>').text('Crates'));
+            div.className = 'block crate';
-            var ul = $('<ul>').appendTo(div);
+            div.innerHTML = '<h3>Crates</h3>';
+            var ul = document.createElement('ul');
+            div.appendChild(ul);
 
             var crates = [];
             for (var crate in rawSearchIndex) {
@@ -828,12 +994,17 @@
                 if (crates[i] === window.currentCrate) {
                     klass += ' current';
                 }
-                var link = $('<a>', {'href': '../' + crates[i] + '/index.html',
+                var link = document.createElement('a');
-                                     'title': rawSearchIndex[crates[i]].doc,
+                link.href = '../' + crates[i] + '/index.html';
-                                     'class': klass}).text(crates[i]);
+                link.title = rawSearchIndex[crates[i]].doc;
-                ul.append($('<li>').append(link));
+                link.className = klass;
+                link.textContent = crates[i];
+
+                var li = document.createElement('li');
+                li.appendChild(link);
+                ul.appendChild(li);
             }
-            sidebar.append(div);
+            sidebar.appendChild(div);
         }
     }
 
@@ -841,16 +1012,19 @@
 
     // delayed sidebar rendering.
     function initSidebarItems(items) {
-        var sidebar = $('.sidebar');
+        var sidebar = document.getElementsByClassName('sidebar')[0];
         var current = window.sidebarCurrent;
 
         function block(shortty, longty) {
             var filtered = items[shortty];
             if (!filtered) { return; }
 
-            var div = $('<div>').attr('class', 'block ' + shortty);
+            var div = document.createElement('div');
-            div.append($('<h3>').text(longty));
+            div.className = 'block ' + shortty;
-            var ul = $('<ul>').appendTo(div);
+            var h3 = document.createElement('h3');
+            h3.textContent = longty;
+            div.appendChild(h3);
+            var ul = document.createElement('ul');
 
             for (var i = 0; i < filtered.length; ++i) {
                 var item = filtered[i];
@@ -867,12 +1041,17 @@
                 } else {
                     path = shortty + '.' + name + '.html';
                 }
-                var link = $('<a>', {'href': current.relpath + path,
+                var link = document.createElement('a');
-                                     'title': desc,
+                link.href = current.relpath + path;
-                                     'class': klass}).text(name);
+                link.title = desc;
-                ul.append($('<li>').append(link));
+                link.className = klass;
+                link.textContent = name;
+                var li = document.createElement('li');
+                li.appendChild(link);
+                ul.appendChild(li);
             }
-            sidebar.append(div);
+            div.appendChild(ul);
+            sidebar.appendChild(div);
         }
 
         block("primitive", "Primitive Types");
@@ -890,21 +1069,25 @@
     window.initSidebarItems = initSidebarItems;
 
     window.register_implementors = function(imp) {
-        var list = $('#implementors-list');
+        var list = document.getElementById('implementors-list');
         var libs = Object.getOwnPropertyNames(imp);
         for (var i = 0; i < libs.length; ++i) {
             if (libs[i] === currentCrate) { continue; }
             var structs = imp[libs[i]];
             for (var j = 0; j < structs.length; ++j) {
-                var code = $('<code>').append(structs[j]);
+                var code = document.createElement('code');
-                $.each(code.find('a'), function(idx, a) {
+                code.innerHTML = structs[j];
-                    var href = $(a).attr('href');
+
+                var x = code.getElementsByTagName('a');
+                for (var i = 0; i < x.length; i++) {
+                    var href = x[i].href;
                     if (href && href.indexOf('http') !== 0) {
-                        $(a).attr('href', rootPath + href);
+                        x[i].href = rootPath + href;
                     }
-                });
+                }
-                var li = $('<li>').append(code);
+                var li = document.createElement('li');
-                list.append(li);
+                li.appendChild(code);
+                list.appendChild(li);
             }
         }
     };
@@ -922,146 +1105,186 @@
         return "\u2212"; // "\u2212" is '−' minus sign
     }
 
-    function toggleAllDocs() {
+    function onEveryMatchingChild(elem, className, func) {
-        var toggle = $("#toggle-all-docs");
+        if (elem && className && func) {
-        if (toggle.hasClass("will-expand")) {
+            for (var i = 0; i < elem.childNodes.length; i++) {
-            toggle.removeClass("will-expand");
+                if (hasClass(elem.childNodes[i], className)) {
-            toggle.children(".inner").text(labelForToggleButton(false));
+                    func(elem.childNodes[i]);
-            toggle.attr("title", "collapse all docs");
-            $(".docblock").show();
-            $(".toggle-label").hide();
-            $(".toggle-wrapper").removeClass("collapsed");
-            $(".collapse-toggle").children(".inner").text(labelForToggleButton(false));
-        } else {
-            toggle.addClass("will-expand");
-            toggle.children(".inner").text(labelForToggleButton(true));
-            toggle.attr("title", "expand all docs");
-            $(".docblock").hide();
-            $(".toggle-label").show();
-            $(".toggle-wrapper").addClass("collapsed");
-            $(".collapse-toggle").children(".inner").text(labelForToggleButton(true));
-        }
-    }
-
-    function collapseDocs(toggle, animate) {
-        var relatedDoc = toggle.parent().next();
-        if (relatedDoc.is(".stability")) {
-            relatedDoc = relatedDoc.next();
-        }
-        if (relatedDoc.is(".docblock")) {
-            if (relatedDoc.is(":visible")) {
-                if (animate === true) {
-                    relatedDoc.slideUp({
-                        duration: 'fast',
-                        easing: 'linear',
-                        complete: function() {
-                            toggle.children(".toggle-label").fadeIn();
-                            toggle.parent(".toggle-wrapper").addClass("collapsed");
-                            toggle.children(".inner").text(labelForToggleButton(true));
-                        },
-                    });
                 } else {
-                    relatedDoc.hide();
+                    onEveryMatchingChild(elem.childNodes[i], className, func);
-                    toggle.children(".toggle-label").show();
-                    toggle.parent(".toggle-wrapper").addClass("collapsed");
-                    toggle.children(".inner").text(labelForToggleButton(true));
                 }
-            } else {
-                relatedDoc.slideDown({duration: 'fast', easing: 'linear'});
-                toggle.parent(".toggle-wrapper").removeClass("collapsed");
-                toggle.children(".inner").text(labelForToggleButton(false));
-                toggle.children(".toggle-label").hide();
             }
         }
     }
 
-    $("#toggle-all-docs").on("click", toggleAllDocs);
+    function toggleAllDocs() {
+        var toggle = document.getElementById("toggle-all-docs");
+        if (hasClass(toggle, "will-expand")) {
+            removeClass(toggle, "will-expand");
+            onEveryMatchingChild(toggle, "inner", function(e) {
+                e.innerHTML = labelForToggleButton(false);
+            });
+            toggle.title = "collapse all docs";
+            onEach(document.getElementsByClassName("docblock"), function(e) {
+                e.style.display = 'block';
+            });
+            onEach(document.getElementsByClassName("toggle-label"), function(e) {
+                e.style.display = 'none';
+            });
+            onEach(document.getElementsByClassName("toggle-wrapper"), function(e) {
+                removeClass(e, "collapsed");
+            });
+            onEach(document.getElementsByClassName("collapse-toggle"), function(e) {
+                onEveryMatchingChild(e, "inner", function(i_e) {
+                    i_e.innerHTML = labelForToggleButton(false);
+                });
+            });
+        } else {
+            addClass(toggle, "will-expand");
+            onEveryMatchingChild(toggle, "inner", function(e) {
+                e.innerHTML = labelForToggleButton(true);
+            });
+            toggle.title = "expand all docs";
+            onEach(document.getElementsByClassName("docblock"), function(e) {
+                e.style.display = 'none';
+            });
+            onEach(document.getElementsByClassName("toggle-label"), function(e) {
+                e.style.display = 'inline-block';
+            });
+            onEach(document.getElementsByClassName("toggle-wrapper"), function(e) {
+                addClass(e, "collapsed");
+            });
+            onEach(document.getElementsByClassName("collapse-toggle"), function(e) {
+                onEveryMatchingChild(e, "inner", function(i_e) {
+                    i_e.innerHTML = labelForToggleButton(true);
+                });
+            });
+        }
+    }
 
-    $(document).on("click", ".collapse-toggle", function() {
+    function collapseDocs(toggle) {
-        collapseDocs($(this), true)
+        if (!toggle || !toggle.parentNode) {
-    });
+            return;
-
+        }
-    $(function() {
+        var relatedDoc = toggle.parentNode.nextElementSibling;
-        var toggle = $("<a/>", {'href': 'javascript:void(0)', 'class': 'collapse-toggle'})
+        if (hasClass(relatedDoc, "stability")) {
-            .html("[<span class='inner'></span>]");
+            relatedDoc = relatedDoc.nextElementSibling;
-        toggle.children(".inner").text(labelForToggleButton(false));
+        }
-
+        if (hasClass(relatedDoc, "docblock")) {
-        $(".method, .impl-items > .associatedconstant").each(function() {
+            if (!isHidden(relatedDoc)) {
-            if ($(this).next().is(".docblock") ||
+                relatedDoc.style.display = 'none';
-                ($(this).next().is(".stability") && $(this).next().next().is(".docblock"))) {
+                onEach(toggle.childNodes, function(e) {
-                    $(this).children().last().after(toggle.clone());
+                    if (hasClass(e, 'toggle-label')) {
-            }
+                        e.style.display = 'inline-block';
-        });
+                    }
-
+                    if (hasClass(e, 'inner')) {
-        var mainToggle =
+                        e.innerHTML = labelForToggleButton(true);
-            $(toggle.clone()).append(
+                    }
-                $('<span/>', {'class': 'toggle-label'})
+                });
-                    .css('display', 'none')
+                addClass(toggle.parentNode, 'collapsed');
-                    .html('&nbsp;Expand&nbsp;description'));
-        var wrapper = $("<div class='toggle-wrapper'>").append(mainToggle);
-        $("#main > .docblock").before(wrapper);
-
-        $(".docblock.autohide").each(function() {
-            var wrap = $(this).prev();
-            if (wrap.is(".toggle-wrapper")) {
-                var toggle = wrap.children().first();
-                if ($(this).children().first().is("h3")) {
-                    toggle.children(".toggle-label")
-                          .text(" Show " + $(this).children().first().text());
-                }
-                $(this).hide();
-                wrap.addClass("collapsed");
-                toggle.children(".inner").text(labelForToggleButton(true));
-                toggle.children(".toggle-label").show();
-            }
-        });
-
-        var mainToggle =
-            $(toggle).append(
-                $('<span/>', {'class': 'toggle-label'})
-                    .css('display', 'none')
-                    .html('&nbsp;Expand&nbsp;attributes'));
-        var wrapper = $("<div class='toggle-wrapper toggle-attributes'>").append(mainToggle);
-        $("#main > pre > .attributes").each(function() {
-            $(this).before(wrapper);
-            collapseDocs($($(this).prev().children()[0]), false);
-        });
-    });
-
-    $('pre.line-numbers').on('click', 'span', function() {
-        var prev_id = 0;
-
-        function set_fragment(name) {
-            if (browserSupportsHistoryApi()) {
-                history.replaceState(null, null, '#' + name);
-                $(window).trigger('hashchange');
             } else {
-                location.replace('#' + name);
+                relatedDoc.style.display = 'block';
+                removeClass(toggle.parentNode, 'collapsed');
+                onEach(toggle.childNodes, function(e) {
+                    if (hasClass(e, 'toggle-label')) {
+                        e.style.display = 'none';
+                    }
+                    if (hasClass(e, 'inner')) {
+                        e.innerHTML = labelForToggleButton(false);
+                    }
+                });
             }
         }
+    }
 
-        return function(ev) {
+    var x = document.getElementById('toggle-all-docs');
-            var cur_id = parseInt(ev.target.id, 10);
+    if (x) {
+        x.onclick = toggleAllDocs;
+    }
 
-            if (ev.shiftKey && prev_id) {
+    function insertAfter(newNode, referenceNode) {
-                if (prev_id > cur_id) {
+        referenceNode.parentNode.insertBefore(newNode, referenceNode.nextSibling);
-                    var tmp = prev_id;
+    }
-                    prev_id = cur_id;
+
-                    cur_id = tmp;
+    var toggle = document.createElement('a');
+    toggle.href = 'javascript:void(0)';
+    toggle.className = 'collapse-toggle';
+    toggle.innerHTML = "[<span class='inner'>"+labelForToggleButton(false)+"</span>]";
+
+    var func = function(e) {
+        var next = e.nextElementSibling;
+        if (!next) {
+            return;
+        }
+        if (hasClass(next, 'docblock') ||
+            (hasClass(next, 'stability') &&
+             hasClass(next.nextElementSibling, 'docblock'))) {
+            insertAfter(toggle.cloneNode(true), e.childNodes[e.childNodes.length - 1]);
+        }
+    }
+    onEach(document.getElementsByClassName('method'), func);
+    onEach(document.getElementsByClassName('impl-items'), function(e) {
+        onEach(e.getElementsByClassName('associatedconstant'), func);
+    });
+
+    var span = document.createElement('span');
+    span.className = 'toggle-label';
+    span.style.display = 'none';
+    span.innerHTML = '&nbsp;Expand&nbsp;description';
+
+    var mainToggle = toggle.cloneNode(true);
+    mainToggle.appendChild(span);
+
+    var wrapper = document.createElement('div');
+    wrapper.className = 'toggle-wrapper';
+    wrapper.appendChild(mainToggle);
+
+    onEach(document.getElementById('main').getElementsByClassName('docblock'), function(e) {
+        if (e.parentNode.id === "main") {
+            e.parentNode.insertBefore(wrapper, e);
+        }
+    });
+
+    onEach(document.getElementsByClassName('docblock'), function(e) {
+        if (hasClass(e, 'autohide')) {
+            var wrap = e.previousElementSibling;
+            if (wrap && hasClass(wrap, 'toggle-wrapper')) {
+                var toggle = wrap.childNodes[0];
+                if (e.childNodes[0].tagName === 'H3') {
+                    onEach(toggle.getElementsByClassName('toggle-label'), function(i_e) {
+                        i_e.innerHTML = " Show " + e.childNodes[0].innerHTML;
+                    });
                 }
-
+                e.style.display = 'none';
-                set_fragment(prev_id + '-' + cur_id);
+                addClass(wrap, 'collapsed');
-            } else {
+                onEach(toggle.getElementsByClassName('inner'), function(e) {
-                prev_id = cur_id;
+                    e.innerHTML = labelForToggleButton(true);
-
+                });
-                set_fragment(cur_id);
+                onEach(toggle.getElementsByClassName('toggle-label'), function(e) {
+                    e.style.display = 'block';
+                });
             }
-        };
+        }
-    }());
+    })
 
+    var span = document.createElement('span');
+    span.className = 'toggle-label';
+    span.style.display = 'none';
+    span.innerHTML = '&nbsp;Expand&nbsp;attributes';
+    toggle.appendChild(span);
+
+    var wrapper = document.createElement('div');
+    wrapper.className = 'toggle-wrapper toggle-attributes';
+    wrapper.appendChild(toggle);
+    onEach(document.getElementById('main').getElementsByTagName('pre'), function(e) {
+        onEach(e.getElementsByClassName('attributes'), function(i_e) {
+            i_e.parentNode.insertBefore(wrapper, i_e);
+            collapseDocs(i_e.previousSibling.childNodes[0]);
+        });
+    });
 }());
 
 // Sets the focus on the search bar at the top of the page
 function focusSearchBar() {
-    $('.search-input').focus();
+    document.getElementsByClassName('search-input')[0].focus();
 }

src/librustdoc/lib.rs

@@ -173,6 +173,7 @@ pub fn opts() -> Vec<RustcOptGroup> {
                          or `#![doc(html_playground_url=...)]`",
                         "URL")),
         unstable(optflag("", "enable-commonmark", "to enable commonmark doc rendering/testing")),
+        unstable(optflag("", "display-warnings", "to print code warnings when testing doc")),
     ]
 }
 
@@ -280,14 +281,16 @@ pub fn main_args(args: &[String]) -> isize {
     let crate_name = matches.opt_str("crate-name");
     let playground_url = matches.opt_str("playground-url");
     let maybe_sysroot = matches.opt_str("sysroot").map(PathBuf::from);
+    let display_warnings = matches.opt_present("display-warnings");
 
     match (should_test, markdown_input) {
         (true, true) => {
-            return markdown::test(input, cfgs, libs, externs, test_args, maybe_sysroot, render_type)
+            return markdown::test(input, cfgs, libs, externs, test_args, maybe_sysroot, render_type,
+                                  display_warnings)
         }
         (true, false) => {
             return test::run(input, cfgs, libs, externs, test_args, crate_name, maybe_sysroot,
-                             render_type)
+                             render_type, display_warnings)
         }
         (false, true) => return markdown::render(input,
                                                  output.unwrap_or(PathBuf::from("doc")),
@@ -389,13 +392,15 @@ where R: 'static + Send, F: 'static + Send + FnOnce(Output) -> R {
 
     let cr = PathBuf::from(cratefile);
     info!("starting to run rustc");
+    let display_warnings = matches.opt_present("display-warnings");
 
     let (tx, rx) = channel();
     rustc_driver::monitor(move || {
         use rustc::session::config::Input;
 
         let (mut krate, renderinfo) =
-            core::run_core(paths, cfgs, externs, Input::File(cr), triple, maybe_sysroot);
+            core::run_core(paths, cfgs, externs, Input::File(cr), triple, maybe_sysroot,
+                           display_warnings);
 
         info!("finished with rustc");
 

src/librustdoc/markdown.rs

@@ -150,7 +150,7 @@ pub fn render(input: &str, mut output: PathBuf, matches: &getopts::Matches,
 /// Run any tests/code examples in the markdown file `input`.
 pub fn test(input: &str, cfgs: Vec<String>, libs: SearchPaths, externs: Externs,
             mut test_args: Vec<String>, maybe_sysroot: Option<PathBuf>,
-            render_type: RenderType) -> isize {
+            render_type: RenderType, display_warnings: bool) -> isize {
     let input_str = match load_string(input) {
         Ok(s) => s,
         Err(LoadStringError::ReadFail) => return 1,
@@ -166,6 +166,7 @@ pub fn test(input: &str, cfgs: Vec<String>, libs: SearchPaths, externs: Externs,
     old_find_testable_code(&input_str, &mut collector, DUMMY_SP);
     find_testable_code(&input_str, &mut collector, DUMMY_SP);
     test_args.insert(0, "rustdoctest".to_string());
-    testing::test_main(&test_args, collector.tests);
+    testing::test_main(&test_args, collector.tests,
+                       testing::Options::new().display_output(display_warnings));
     0
 }

src/librustdoc/test.rs

@@ -58,7 +58,8 @@ pub fn run(input: &str,
            mut test_args: Vec<String>,
            crate_name: Option<String>,
            maybe_sysroot: Option<PathBuf>,
-           render_type: RenderType)
+           render_type: RenderType,
+           display_warnings: bool)
            -> isize {
     let input_path = PathBuf::from(input);
     let input = config::Input::File(input_path.clone());
@@ -127,7 +128,8 @@ pub fn run(input: &str,
     test_args.insert(0, "rustdoctest".to_string());
 
     testing::test_main(&test_args,
-                       collector.tests.into_iter().collect());
+                       collector.tests.into_iter().collect(),
+                       testing::Options::new().display_output(display_warnings));
     0
 }
 

src/libstd/build.rs

@@ -43,11 +43,16 @@ fn main() {
         println!("cargo:rustc-link-lib=pthread");
     } else if target.contains("apple-darwin") {
         println!("cargo:rustc-link-lib=System");
+
+        // res_init and friends require -lresolv on macOS/iOS.
+        // See #41582 and http://blog.achernya.com/2013/03/os-x-has-silly-libsystem.html
+        println!("cargo:rustc-link-lib=resolv");
     } else if target.contains("apple-ios") {
         println!("cargo:rustc-link-lib=System");
         println!("cargo:rustc-link-lib=objc");
         println!("cargo:rustc-link-lib=framework=Security");
         println!("cargo:rustc-link-lib=framework=Foundation");
+        println!("cargo:rustc-link-lib=resolv");
     } else if target.contains("windows") {
         println!("cargo:rustc-link-lib=advapi32");
         println!("cargo:rustc-link-lib=ws2_32");

src/libstd/collections/hash/table.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use alloc::heap::{EMPTY, allocate, deallocate};
+use alloc::heap::{allocate, deallocate};
 
 use cmp;
 use hash::{BuildHasher, Hash, Hasher};
@@ -33,6 +33,7 @@ use self::BucketState::*;
 type HashUint = usize;
 
 const EMPTY_BUCKET: HashUint = 0;
+const EMPTY: usize = 1;
 
 /// Special `Unique<HashUint>` that uses the lower bit of the pointer
 /// to expose a boolean tag.
@@ -49,24 +50,25 @@ impl TaggedHashUintPtr {
 
     #[inline]
     fn set_tag(&mut self, value: bool) {
-        let usize_ptr = &*self.0 as *const *mut HashUint as *mut usize;
+        let mut usize_ptr = self.0.as_ptr() as usize;
         unsafe {
             if value {
-                *usize_ptr |= 1;
+                usize_ptr |= 1;
             } else {
-                *usize_ptr &= !1;
+                usize_ptr &= !1;
             }
+            self.0 = Unique::new(usize_ptr as *mut HashUint)
         }
     }
 
     #[inline]
     fn tag(&self) -> bool {
-        (*self.0 as usize) & 1 == 1
+        (self.0.as_ptr() as usize) & 1 == 1
     }
 
     #[inline]
     fn ptr(&self) -> *mut HashUint {
-        (*self.0 as usize & !1) as *mut HashUint
+        (self.0.as_ptr() as usize & !1) as *mut HashUint
     }
 }
 
@@ -1112,10 +1114,12 @@ impl<'a, K, V> Iterator for Drain<'a, K, V> {
 
     #[inline]
     fn next(&mut self) -> Option<(SafeHash, K, V)> {
-        self.iter.next().map(|raw| unsafe {
+        self.iter.next().map(|raw| {
-            (*self.table.as_mut_ptr()).size -= 1;
+            unsafe {
-            let (k, v) = ptr::read(raw.pair());
+                self.table.as_mut().size -= 1;
-            (SafeHash { hash: ptr::replace(&mut *raw.hash(), EMPTY_BUCKET) }, k, v)
+                let (k, v) = ptr::read(raw.pair());
+                (SafeHash { hash: ptr::replace(&mut *raw.hash(), EMPTY_BUCKET) }, k, v)
+            }
         })
     }
 

src/libstd/sys/unix/thread_local.rs

@@ -38,3 +38,8 @@ pub unsafe fn destroy(key: Key) {
     let r = libc::pthread_key_delete(key);
     debug_assert_eq!(r, 0);
 }
+
+#[inline]
+pub fn requires_synchronized_create() -> bool {
+    false
+}

src/libstd/sys/windows/c.rs

@@ -935,7 +935,6 @@ extern "system" {
                           args: *const c_void)
                           -> DWORD;
     pub fn TlsAlloc() -> DWORD;
-    pub fn TlsFree(dwTlsIndex: DWORD) -> BOOL;
     pub fn TlsGetValue(dwTlsIndex: DWORD) -> LPVOID;
     pub fn TlsSetValue(dwTlsIndex: DWORD, lpTlsvalue: LPVOID) -> BOOL;
     pub fn GetLastError() -> DWORD;

src/libstd/sys/windows/thread_local.rs

@@ -8,10 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use mem;
 use ptr;
+use sync::atomic::AtomicPtr;
+use sync::atomic::Ordering::SeqCst;
 use sys::c;
-use sys_common::mutex::Mutex;
-use sys_common;
 
 pub type Key = c::DWORD;
 pub type Dtor = unsafe extern fn(*mut u8);
@@ -34,8 +35,6 @@ pub type Dtor = unsafe extern fn(*mut u8);
 // * All TLS destructors are tracked by *us*, not the windows runtime. This
 //   means that we have a global list of destructors for each TLS key that
 //   we know about.
-// * When a TLS key is destroyed, we're sure to remove it from the dtor list
-//   if it's in there.
 // * When a thread exits, we run over the entire list and run dtors for all
 //   non-null keys. This attempts to match Unix semantics in this regard.
 //
@@ -50,13 +49,6 @@ pub type Dtor = unsafe extern fn(*mut u8);
 // [2]: https://github.com/ChromiumWebApps/chromium/blob/master/base
 //                        /threading/thread_local_storage_win.cc#L42
 
-// NB these are specifically not types from `std::sync` as they currently rely
-// on poisoning and this module needs to operate at a lower level than requiring
-// the thread infrastructure to be in place (useful on the borders of
-// initialization/destruction).
-static DTOR_LOCK: Mutex = Mutex::new();
-static mut DTORS: *mut Vec<(Key, Dtor)> = ptr::null_mut();
-
 // -------------------------------------------------------------------------
 // Native bindings
 //
@@ -85,81 +77,64 @@ pub unsafe fn get(key: Key) -> *mut u8 {
 }
 
 #[inline]
-pub unsafe fn destroy(key: Key) {
+pub unsafe fn destroy(_key: Key) {
-    if unregister_dtor(key) {
+    rtabort!("can't destroy tls keys on windows")
-        // FIXME: Currently if a key has a destructor associated with it we
+}
-        // can't actually ever unregister it. If we were to
+
-        // unregister it, then any key destruction would have to be
+#[inline]
-        // serialized with respect to actually running destructors.
+pub fn requires_synchronized_create() -> bool {
-        //
+    true
-        // We want to avoid a race where right before run_dtors runs
-        // some destructors TlsFree is called. Allowing the call to
-        // TlsFree would imply that the caller understands that *all
-        // known threads* are not exiting, which is quite a difficult
-        // thing to know!
-        //
-        // For now we just leak all keys with dtors to "fix" this.
-        // Note that source [2] above shows precedent for this sort
-        // of strategy.
-    } else {
-        let r = c::TlsFree(key);
-        debug_assert!(r != 0);
-    }
 }
 
 // -------------------------------------------------------------------------
 // Dtor registration
 //
-// These functions are associated with registering and unregistering
+// Windows has no native support for running destructors so we manage our own
-// destructors. They're pretty simple, they just push onto a vector and scan
+// list of destructors to keep track of how to destroy keys. We then install a
-// a vector currently.
+// callback later to get invoked whenever a thread exits, running all
+// appropriate destructors.
 //
-// FIXME: This could probably be at least a little faster with a BTree.
+// Currently unregistration from this list is not supported. A destructor can be
+// registered but cannot be unregistered. There's various simplifying reasons
+// for doing this, the big ones being:
+//
+// 1. Currently we don't even support deallocating TLS keys, so normal operation
+//    doesn't need to deallocate a destructor.
+// 2. There is no point in time where we know we can unregister a destructor
+//    because it could always be getting run by some remote thread.
+//
+// Typically processes have a statically known set of TLS keys which is pretty
+// small, and we'd want to keep this memory alive for the whole process anyway
+// really.
+//
+// Perhaps one day we can fold the `Box` here into a static allocation,
+// expanding the `StaticKey` structure to contain not only a slot for the TLS
+// key but also a slot for the destructor queue on windows. An optimization for
+// another day!
 
-unsafe fn init_dtors() {
+static DTORS: AtomicPtr<Node> = AtomicPtr::new(ptr::null_mut());
-    if !DTORS.is_null() { return }
 
-    let dtors = box Vec::<(Key, Dtor)>::new();
+struct Node {
-
+    dtor: Dtor,
-    let res = sys_common::at_exit(move|| {
+    key: Key,
-        DTOR_LOCK.lock();
+    next: *mut Node,
-        let dtors = DTORS;
-        DTORS = 1 as *mut _;
-        Box::from_raw(dtors);
-        assert!(DTORS as usize == 1); // can't re-init after destructing
-        DTOR_LOCK.unlock();
-    });
-    if res.is_ok() {
-        DTORS = Box::into_raw(dtors);
-    } else {
-        DTORS = 1 as *mut _;
-    }
 }
 
 unsafe fn register_dtor(key: Key, dtor: Dtor) {
-    DTOR_LOCK.lock();
+    let mut node = Box::new(Node {
-    init_dtors();
+        key: key,
-    assert!(DTORS as usize != 0);
+        dtor: dtor,
-    assert!(DTORS as usize != 1,
+        next: ptr::null_mut(),
-            "cannot create new TLS keys after the main thread has exited");
+    });
-    (*DTORS).push((key, dtor));
-    DTOR_LOCK.unlock();
-}
 
-unsafe fn unregister_dtor(key: Key) -> bool {
+    let mut head = DTORS.load(SeqCst);
-    DTOR_LOCK.lock();
+    loop {
-    init_dtors();
+        node.next = head;
-    assert!(DTORS as usize != 0);
+        match DTORS.compare_exchange(head, &mut *node, SeqCst, SeqCst) {
-    assert!(DTORS as usize != 1,
+            Ok(_) => return mem::forget(node),
-            "cannot unregister destructors after the main thread has exited");
+            Err(cur) => head = cur,
-    let ret = {
+        }
-        let dtors = &mut *DTORS;
+    }
-        let before = dtors.len();
-        dtors.retain(|&(k, _)| k != key);
-        dtors.len() != before
-    };
-    DTOR_LOCK.unlock();
-    ret
 }
 
 // -------------------------------------------------------------------------
@@ -196,16 +171,12 @@ unsafe fn unregister_dtor(key: Key) -> bool {
 // # Ok, what's up with running all these destructors?
 //
 // This will likely need to be improved over time, but this function
-// attempts a "poor man's" destructor callback system. To do this we clone a
+// attempts a "poor man's" destructor callback system. Once we've got a list
-// local copy of the dtor list to start out with. This is our fudgy attempt
+// of what to run, we iterate over all keys, check their values, and then run
-// to not hold the lock while destructors run and not worry about the list
+// destructors if the values turn out to be non null (setting them to null just
-// changing while we're looking at it.
+// beforehand). We do this a few times in a loop to basically match Unix
-//
+// semantics. If we don't reach a fixed point after a short while then we just
-// Once we've got a list of what to run, we iterate over all keys, check
+// inevitably leak something most likely.
-// their values, and then run destructors if the values turn out to be non
-// null (setting them to null just beforehand). We do this a few times in a
-// loop to basically match Unix semantics. If we don't reach a fixed point
-// after a short while then we just inevitably leak something most likely.
 //
 // # The article mentions weird stuff about "/INCLUDE"?
 //
@@ -259,25 +230,21 @@ unsafe extern "system" fn on_tls_callback(h: c::LPVOID,
 unsafe fn run_dtors() {
     let mut any_run = true;
     for _ in 0..5 {
-        if !any_run { break }
+        if !any_run {
+            break
+        }
         any_run = false;
-        let dtors = {
+        let mut cur = DTORS.load(SeqCst);
-            DTOR_LOCK.lock();
+        while !cur.is_null() {
-            let ret = if DTORS as usize <= 1 {
+            let ptr = c::TlsGetValue((*cur).key);
-                Vec::new()
+
-            } else {
-                (*DTORS).iter().map(|s| *s).collect()
-            };
-            DTOR_LOCK.unlock();
-            ret
-        };
-        for &(key, dtor) in &dtors {
-            let ptr = c::TlsGetValue(key);
             if !ptr.is_null() {
-                c::TlsSetValue(key, ptr::null_mut());
+                c::TlsSetValue((*cur).key, ptr::null_mut());
-                dtor(ptr as *mut _);
+                ((*cur).dtor)(ptr as *mut _);
                 any_run = true;
             }
+
+            cur = (*cur).next;
         }
     }
 }

src/libstd/sys_common/net.rs

@@ -177,9 +177,22 @@ pub fn lookup_host(host: &str) -> io::Result<LookupHost> {
     };
     let mut res = ptr::null_mut();
     unsafe {
-        cvt_gai(c::getaddrinfo(c_host.as_ptr(), ptr::null(), &hints,
+        match cvt_gai(c::getaddrinfo(c_host.as_ptr(), ptr::null(), &hints, &mut res)) {
-                               &mut res))?;
+            Ok(_) => {
-        Ok(LookupHost { original: res, cur: res })
+                Ok(LookupHost { original: res, cur: res })
+            },
+            #[cfg(unix)]
+            Err(e) => {
+                // The lookup failure could be caused by using a stale /etc/resolv.conf.
+                // See https://github.com/rust-lang/rust/issues/41570.
+                // We therefore force a reload of the nameserver information.
+                c::res_init();
+                Err(e)
+            },
+            // the cfg is needed here to avoid an "unreachable pattern" warning
+            #[cfg(not(unix))]
+            Err(e) => Err(e),
+        }
     }
 }
 

src/libstd/sys_common/thread_local.rs

@@ -61,6 +61,7 @@
 use sync::atomic::{self, AtomicUsize, Ordering};
 
 use sys::thread_local as imp;
+use sys_common::mutex::Mutex;
 
 /// A type for TLS keys that are statically allocated.
 ///
@@ -145,20 +146,6 @@ impl StaticKey {
     #[inline]
     pub unsafe fn set(&self, val: *mut u8) { imp::set(self.key(), val) }
 
-    /// Deallocates this OS TLS key.
-    ///
-    /// This function is unsafe as there is no guarantee that the key is not
-    /// currently in use by other threads or will not ever be used again.
-    ///
-    /// Note that this does *not* run the user-provided destructor if one was
-    /// specified at definition time. Doing so must be done manually.
-    pub unsafe fn destroy(&self) {
-        match self.key.swap(0, Ordering::SeqCst) {
-            0 => {}
-            n => { imp::destroy(n as imp::Key) }
-        }
-    }
-
     #[inline]
     unsafe fn key(&self) -> imp::Key {
         match self.key.load(Ordering::Relaxed) {
@@ -168,6 +155,24 @@ impl StaticKey {
     }
 
     unsafe fn lazy_init(&self) -> usize {
+        // Currently the Windows implementation of TLS is pretty hairy, and
+        // it greatly simplifies creation if we just synchronize everything.
+        //
+        // Additionally a 0-index of a tls key hasn't been seen on windows, so
+        // we just simplify the whole branch.
+        if imp::requires_synchronized_create() {
+            static INIT_LOCK: Mutex = Mutex::new();
+            INIT_LOCK.lock();
+            let mut key = self.key.load(Ordering::SeqCst);
+            if key == 0 {
+                key = imp::create(self.dtor) as usize;
+                self.key.store(key, Ordering::SeqCst);
+            }
+            INIT_LOCK.unlock();
+            assert!(key != 0);
+            return key
+        }
+
         // POSIX allows the key created here to be 0, but the compare_and_swap
         // below relies on using 0 as a sentinel value to check who won the
         // race to set the shared TLS key. As far as I know, there is no
@@ -227,7 +232,9 @@ impl Key {
 
 impl Drop for Key {
     fn drop(&mut self) {
-        unsafe { imp::destroy(self.key) }
+        // Right now Windows doesn't support TLS key destruction, but this also
+        // isn't used anywhere other than tests, so just leak the TLS key.
+        // unsafe { imp::destroy(self.key) }
     }
 }
 

src/libstd_unicode/tables.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// NOTE: The following code was generated by "src/etc/unicode.py", do not edit directly
+// NOTE: The following code was generated by "./unicode.py", do not edit directly
 
 #![allow(missing_docs, non_upper_case_globals, non_snake_case)]
 

src/libstd_unicode/unicode.py

@@ -35,7 +35,7 @@ preamble = '''// Copyright 2012-2016 The Rust Project Developers. See the COPYRI
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// NOTE: The following code was generated by "src/etc/unicode.py", do not edit directly
+// NOTE: The following code was generated by "./unicode.py", do not edit directly
 
 #![allow(missing_docs, non_upper_case_globals, non_snake_case)]
 '''

src/libsyntax/parse/parser.rs

@@ -2700,6 +2700,19 @@ impl<'a> Parser<'a> {
                 let (span, e) = self.interpolated_or_expr_span(e)?;
                 (span, self.mk_unary(UnOp::Not, e))
             }
+            // Suggest `!` for bitwise negation when encountering a `~`
+            token::Tilde => {
+                self.bump();
+                let e = self.parse_prefix_expr(None);
+                let (span, e) = self.interpolated_or_expr_span(e)?;
+                let span_of_tilde = lo;
+                let mut err = self.diagnostic().struct_span_err(span_of_tilde,
+                        "`~` can not be used as an unary operator");
+                err.span_label(span_of_tilde, &"did you mean `!`?");
+                err.help("use `!` instead of `~` if you meant to perform bitwise negation");
+                err.emit();
+                (span, self.mk_unary(UnOp::Not, e))
+            }
             token::BinOp(token::Minus) => {
                 self.bump();
                 let e = self.parse_prefix_expr(None);

src/libsyntax/test.rs

@@ -442,7 +442,7 @@ We're going to be building a module that looks more or less like:
 mod __test {
   extern crate test (name = "test", vers = "...");
   fn main() {
-    test::test_main_static(&::os::args()[], tests)
+    test::test_main_static(&::os::args()[], tests, test::Options::new())
   }
 
   static tests : &'static [test::TestDescAndFn] = &[
@@ -478,7 +478,7 @@ fn mk_main(cx: &mut TestCtxt) -> P<ast::Item> {
     //        pub fn main() {
     //            #![main]
     //            use std::slice::AsSlice;
-    //            test::test_main_static(::std::os::args().as_slice(), TESTS);
+    //            test::test_main_static(::std::os::args().as_slice(), TESTS, test::Options::new());
     //        }
 
     let sp = ignored_span(cx, DUMMY_SP);

src/libtest/lib.rs

@@ -76,7 +76,7 @@ pub mod test {
     pub use {Bencher, TestName, TestResult, TestDesc, TestDescAndFn, TestOpts, TrFailed,
              TrFailedMsg, TrIgnored, TrOk, Metric, MetricMap, StaticTestFn, StaticTestName,
              DynTestName, DynTestFn, run_test, test_main, test_main_static, filter_tests,
-             parse_opts, StaticBenchFn, ShouldPanic};
+             parse_opts, StaticBenchFn, ShouldPanic, Options};
 }
 
 pub mod stats;
@@ -252,14 +252,34 @@ impl Clone for MetricMap {
     }
 }
 
+/// In case we want to add other options as well, just add them in this struct.
+#[derive(Copy, Clone, Debug)]
+pub struct Options {
+    display_output: bool,
+}
+
+impl Options {
+    pub fn new() -> Options {
+        Options {
+            display_output: false,
+        }
+    }
+
+    pub fn display_output(mut self, display_output: bool) -> Options {
+        self.display_output = display_output;
+        self
+    }
+}
+
 // The default console test runner. It accepts the command line
 // arguments and a vector of test_descs.
-pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>) {
+pub fn test_main(args: &[String], tests: Vec<TestDescAndFn>, options: Options) {
-    let opts = match parse_opts(args) {
+    let mut opts = match parse_opts(args) {
         Some(Ok(o)) => o,
         Some(Err(msg)) => panic!("{:?}", msg),
         None => return,
     };
+    opts.options = options;
     if opts.list {
         if let Err(e) = list_tests_console(&opts, tests) {
             panic!("io error when listing tests: {:?}", e);
@@ -301,16 +321,17 @@ pub fn test_main_static(tests: &[TestDescAndFn]) {
                                }
                            })
                            .collect();
-    test_main(&args, owned_tests)
+    test_main(&args, owned_tests, Options::new())
 }
 
-#[derive(Copy, Clone)]
+#[derive(Copy, Clone, Debug)]
 pub enum ColorConfig {
     AutoColor,
     AlwaysColor,
     NeverColor,
 }
 
+#[derive(Debug)]
 pub struct TestOpts {
     pub list: bool,
     pub filter: Option<String>,
@@ -324,6 +345,7 @@ pub struct TestOpts {
     pub quiet: bool,
     pub test_threads: Option<usize>,
     pub skip: Vec<String>,
+    pub options: Options,
 }
 
 impl TestOpts {
@@ -342,6 +364,7 @@ impl TestOpts {
             quiet: false,
             test_threads: None,
             skip: vec![],
+            options: Options::new(),
         }
     }
 }
@@ -481,6 +504,7 @@ pub fn parse_opts(args: &[String]) -> Option<OptRes> {
         quiet: quiet,
         test_threads: test_threads,
         skip: matches.opt_strs("skip"),
+        options: Options::new(),
     };
 
     Some(Ok(test_opts))
@@ -521,7 +545,9 @@ struct ConsoleTestState<T> {
     measured: usize,
     metrics: MetricMap,
     failures: Vec<(TestDesc, Vec<u8>)>,
+    not_failures: Vec<(TestDesc, Vec<u8>)>,
     max_name_len: usize, // number of columns to fill when aligning names
+    options: Options,
 }
 
 impl<T: Write> ConsoleTestState<T> {
@@ -547,7 +573,9 @@ impl<T: Write> ConsoleTestState<T> {
             measured: 0,
             metrics: MetricMap::new(),
             failures: Vec::new(),
+            not_failures: Vec::new(),
             max_name_len: 0,
+            options: opts.options,
         })
     }
 
@@ -703,9 +731,38 @@ impl<T: Write> ConsoleTestState<T> {
         Ok(())
     }
 
+    pub fn write_outputs(&mut self) -> io::Result<()> {
+        self.write_plain("\nsuccesses:\n")?;
+        let mut successes = Vec::new();
+        let mut stdouts = String::new();
+        for &(ref f, ref stdout) in &self.not_failures {
+            successes.push(f.name.to_string());
+            if !stdout.is_empty() {
+                stdouts.push_str(&format!("---- {} stdout ----\n\t", f.name));
+                let output = String::from_utf8_lossy(stdout);
+                stdouts.push_str(&output);
+                stdouts.push_str("\n");
+            }
+        }
+        if !stdouts.is_empty() {
+            self.write_plain("\n")?;
+            self.write_plain(&stdouts)?;
+        }
+
+        self.write_plain("\nsuccesses:\n")?;
+        successes.sort();
+        for name in &successes {
+            self.write_plain(&format!("    {}\n", name))?;
+        }
+        Ok(())
+    }
+
     pub fn write_run_finish(&mut self) -> io::Result<bool> {
         assert!(self.passed + self.failed + self.ignored + self.measured == self.total);
 
+        if self.options.display_output {
+            self.write_outputs()?;
+        }
         let success = self.failed == 0;
         if !success {
             self.write_failures()?;
@@ -824,7 +881,10 @@ pub fn run_tests_console(opts: &TestOpts, tests: Vec<TestDescAndFn>) -> io::Resu
                 st.write_log_result(&test, &result)?;
                 st.write_result(&result)?;
                 match result {
-                    TrOk => st.passed += 1,
+                    TrOk => {
+                        st.passed += 1;
+                        st.not_failures.push((test, stdout));
+                    }
                     TrIgnored => st.ignored += 1,
                     TrMetrics(mm) => {
                         let tname = test.name;
@@ -901,6 +961,8 @@ fn should_sort_failures_before_printing_them() {
         max_name_len: 10,
         metrics: MetricMap::new(),
         failures: vec![(test_b, Vec::new()), (test_a, Vec::new())],
+        options: Options::new(),
+        not_failures: Vec::new(),
     };
 
     st.write_failures().unwrap();

src/test/compile-fail/dep-graph-struct-signature.rs

@@ -58,13 +58,15 @@ mod signatures {
         fn method(&self, x: u32) { }
     }
 
-    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
     struct WillChanges {
+        #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
         x: WillChange,
+        #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
         y: WillChange
     }
 
-    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+    // The fields change, not the type itself.
+    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR no path
     fn indirect(x: WillChanges) { }
 }
 

src/test/compile-fail/dep-graph-type-alias.rs

@@ -23,15 +23,21 @@ fn main() { }
 #[rustc_if_this_changed]
 type TypeAlias = u32;
 
-#[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+// The type alias directly affects the type of the field,
+// not the enclosing struct:
+#[rustc_then_this_would_need(ItemSignature)] //~ ERROR no path
 struct Struct {
+    #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
     x: TypeAlias,
     y: u32
 }
 
-#[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+#[rustc_then_this_would_need(ItemSignature)] //~ ERROR no path
 enum Enum {
-    Variant1(TypeAlias),
+    Variant1 {
+        #[rustc_then_this_would_need(ItemSignature)] //~ ERROR OK
+        t: TypeAlias
+    },
     Variant2(i32)
 }
 

src/test/compile-fail/dep-graph-variance-alias.rs

@@ -0,0 +1,32 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Test that changing what a `type` points to does not go unnoticed
+// by the variance analysis.
+
+// compile-flags: -Z query-dep-graph
+
+#![feature(rustc_attrs)]
+#![allow(dead_code)]
+#![allow(unused_variables)]
+
+fn main() { }
+
+struct Foo<T> {
+    f: T
+}
+
+#[rustc_if_this_changed]
+type TypeAlias<T> = Foo<T>;
+
+#[rustc_then_this_would_need(ItemVariances)] //~ ERROR OK
+struct Use<T> {
+    x: TypeAlias<T>
+}

src/test/compile-fail/variance-regions-direct.rs

@@ -60,7 +60,6 @@ struct Test6<'a, 'b:'a> { //~ ERROR [-, o]
 
 #[rustc_variance]
 struct Test7<'a> { //~ ERROR [*]
-    //~^ ERROR parameter `'a` is never used
     x: isize
 }
 

src/test/compile-fail/variance-regions-indirect.rs

@@ -16,7 +16,6 @@
 
 #[rustc_variance]
 enum Base<'a, 'b, 'c:'b, 'd> { //~ ERROR [+, -, o, *]
-    //~^ ERROR parameter `'d` is never used
     Test8A(extern "Rust" fn(&'a isize)),
     Test8B(&'b [isize]),
     Test8C(&'b mut &'c str),
@@ -24,19 +23,16 @@ enum Base<'a, 'b, 'c:'b, 'd> { //~ ERROR [+, -, o, *]
 
 #[rustc_variance]
 struct Derived1<'w, 'x:'y, 'y, 'z> { //~ ERROR [*, o, -, +]
-    //~^ ERROR parameter `'w` is never used
     f: Base<'z, 'y, 'x, 'w>
 }
 
 #[rustc_variance] // Combine - and + to yield o
 struct Derived2<'a, 'b:'a, 'c> { //~ ERROR [o, o, *]
-    //~^ ERROR parameter `'c` is never used
     f: Base<'a, 'a, 'b, 'c>
 }
 
 #[rustc_variance] // Combine + and o to yield o (just pay attention to 'a here)
 struct Derived3<'a:'b, 'b, 'c> { //~ ERROR [o, -, *]
-    //~^ ERROR parameter `'c` is never used
     f: Base<'a, 'b, 'a, 'c>
 }
 

src/test/compile-fail/variance-trait-bounds.rs

@@ -30,8 +30,7 @@ struct TestStruct<U,T:Setter<U>> { //~ ERROR [+, +]
 }
 
 #[rustc_variance]
-enum TestEnum<U,T:Setter<U>> {//~ ERROR [*, +]
+enum TestEnum<U,T:Setter<U>> { //~ ERROR [*, +]
-    //~^ ERROR parameter `U` is never used
     Foo(T)
 }
 
@@ -51,13 +50,11 @@ trait TestTrait3<U> { //~ ERROR [o, o]
 
 #[rustc_variance]
 struct TestContraStruct<U,T:Setter<U>> { //~ ERROR [*, +]
-    //~^ ERROR parameter `U` is never used
     t: T
 }
 
 #[rustc_variance]
 struct TestBox<U,T:Getter<U>+Setter<U>> { //~ ERROR [*, +]
-    //~^ ERROR parameter `U` is never used
     t: T
 }
 

src/test/run-make/tools.mk

@@ -72,6 +72,7 @@ else
 endif
 else
 ifeq ($(UNAME),Darwin)
+	EXTRACFLAGS := -lresolv
 else
 ifeq ($(UNAME),FreeBSD)
 	EXTRACFLAGS := -lm -lpthread -lgcc_s

src/test/run-pass-fulldeps/auxiliary/issue_24106.rs

@@ -0,0 +1,23 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![crate_type="lib"]
+
+enum E { E0 = 0, E1 = 1 }
+const E0_U8: u8 = E::E0 as u8;
+const E1_U8: u8 = E::E1 as u8;
+
+pub fn go<T>() {
+    match 0 {
+        E0_U8 => (),
+        E1_U8 => (),
+        _ => (),
+    }
+}

src/test/run-pass-fulldeps/issue_24106.rs

@@ -0,0 +1,17 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:issue_24106.rs
+
+extern crate issue_24106;
+
+fn main() {
+    issue_24106::go::<()>();
+}

src/test/ui/did_you_mean/issue-41679.rs

@@ -0,0 +1,13 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+fn main() {
+    let x = ~1;
+}

src/test/ui/did_you_mean/issue-41679.stderr

@@ -0,0 +1,10 @@
+error: `~` can not be used as an unary operator
+  --> $DIR/issue-41679.rs:12:13
+   |
+12 |     let x = ~1;
+   |             ^ did you mean `!`?
+   |
+   = help: use `!` instead of `~` if you meant to perform bitwise negation
+
+error: aborting due to previous error
+

src/tools/compiletest/src/main.rs

@@ -336,6 +336,7 @@ pub fn test_opts(config: &Config) -> test::TestOpts {
         test_threads: None,
         skip: vec![],
         list: false,
+        options: test::Options::new(),
     }
 }
 

src/tools/tidy/src/style.rs

@@ -101,7 +101,7 @@ pub fn check(path: &Path, bad: &mut bool) {
            filename.starts_with(".#") {
             return
         }
-        if filename == "miniz.c" || filename.contains("jquery") {
+        if filename == "miniz.c" {
             return
         }