Rollup of 19 pull requests

src/bootstrap/doc.rs

@@ -697,9 +697,6 @@ impl Step for Rustc {
             return;
         }
 
-        // Build libstd docs so that we generate relative links.
-        builder.ensure(Std { stage, target });
-
         // Build rustc.
         builder.ensure(compile::Rustc { compiler, target });
 
@@ -718,12 +715,16 @@ impl Step for Rustc {
 
         // Find dependencies for top level crates.
         let mut compiler_crates = HashSet::new();
-        for root_crate in &["rustc", "rustc_driver", "rustc_codegen_llvm"] {
+        for root_crate in &["rustc_driver", "rustc_codegen_llvm", "rustc_codegen_ssa"] {
             let interned_root_crate = INTERNER.intern_str(root_crate);
             find_compiler_crates(builder, &interned_root_crate, &mut compiler_crates);
         }
 
         for krate in &compiler_crates {
+            // Create all crate output directories first to make sure rustdoc uses
+            // relative links.
+            // FIXME: Cargo should probably do this itself.
+            t!(fs::create_dir_all(out_dir.join(krate)));
             cargo.arg("-p").arg(krate);
         }
 
@@ -797,8 +798,8 @@ impl Step for Rustdoc {
             return;
         }
 
-        // Build libstd docs so that we generate relative links.
-        builder.ensure(Std { stage, target });
+        // Build rustc docs so that we generate relative links.
+        builder.ensure(Rustc { stage, target });
 
         // Build rustdoc.
         builder.ensure(tool::Rustdoc { host: compiler.host });
@@ -822,6 +823,10 @@ impl Step for Rustdoc {
             &[]
         );
 
+        // Only include compiler crates, no dependencies of those, such as `libc`.
+        cargo.arg("--no-deps");
+        cargo.arg("-p").arg("rustdoc");
+
         cargo.env("RUSTDOCFLAGS", "--document-private-items");
         builder.run(&mut cargo);
     }

src/liballoc/rc.rs

@@ -1187,8 +1187,9 @@ impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Weak<U>> for Weak<T> {}
 
 impl<T> Weak<T> {
     /// Constructs a new `Weak<T>`, without allocating any memory.
-    /// Calling [`upgrade`][Weak::upgrade] on the return value always gives [`None`].
+    /// Calling [`upgrade`] on the return value always gives [`None`].
     ///
+    /// [`upgrade`]: #method.upgrade
     /// [`None`]: ../../std/option/enum.Option.html
     ///
     /// # Examples
@@ -1260,6 +1261,52 @@ impl<T: ?Sized> Weak<T> {
             Some(unsafe { self.ptr.as_ref() })
         }
     }
+
+    /// Returns true if the two `Weak`s point to the same value (not just values
+    /// that compare as equal).
+    ///
+    /// # Notes
+    ///
+    /// Since this compares pointers it means that `Weak::new()` will equal each
+    /// other, even though they don't point to any value.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(weak_ptr_eq)]
+    /// use std::rc::{Rc, Weak};
+    ///
+    /// let first_rc = Rc::new(5);
+    /// let first = Rc::downgrade(&first_rc);
+    /// let second = Rc::downgrade(&first_rc);
+    ///
+    /// assert!(Weak::ptr_eq(&first, &second));
+    ///
+    /// let third_rc = Rc::new(5);
+    /// let third = Rc::downgrade(&third_rc);
+    ///
+    /// assert!(!Weak::ptr_eq(&first, &third));
+    /// ```
+    ///
+    /// Comparing `Weak::new`.
+    ///
+    /// ```
+    /// #![feature(weak_ptr_eq)]
+    /// use std::rc::{Rc, Weak};
+    ///
+    /// let first = Weak::new();
+    /// let second = Weak::new();
+    /// assert!(Weak::ptr_eq(&first, &second));
+    ///
+    /// let third_rc = Rc::new(());
+    /// let third = Rc::downgrade(&third_rc);
+    /// assert!(!Weak::ptr_eq(&first, &third));
+    /// ```
+    #[inline]
+    #[unstable(feature = "weak_ptr_eq", issue = "55981")]
+    pub fn ptr_eq(this: &Self, other: &Self) -> bool {
+        this.ptr.as_ptr() == other.ptr.as_ptr()
+    }
 }
 
 #[stable(feature = "rc_weak", since = "1.4.0")]

src/liballoc/sync.rs

@@ -1130,6 +1130,53 @@ impl<T: ?Sized> Weak<T> {
             Some(unsafe { self.ptr.as_ref() })
         }
     }
+
+    /// Returns true if the two `Weak`s point to the same value (not just values
+    /// that compare as equal).
+    ///
+    /// # Notes
+    ///
+    /// Since this compares pointers it means that `Weak::new()` will equal each
+    /// other, even though they don't point to any value.
+    ///
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(weak_ptr_eq)]
+    /// use std::sync::{Arc, Weak};
+    ///
+    /// let first_rc = Arc::new(5);
+    /// let first = Arc::downgrade(&first_rc);
+    /// let second = Arc::downgrade(&first_rc);
+    ///
+    /// assert!(Weak::ptr_eq(&first, &second));
+    ///
+    /// let third_rc = Arc::new(5);
+    /// let third = Arc::downgrade(&third_rc);
+    ///
+    /// assert!(!Weak::ptr_eq(&first, &third));
+    /// ```
+    ///
+    /// Comparing `Weak::new`.
+    ///
+    /// ```
+    /// #![feature(weak_ptr_eq)]
+    /// use std::sync::{Arc, Weak};
+    ///
+    /// let first = Weak::new();
+    /// let second = Weak::new();
+    /// assert!(Weak::ptr_eq(&first, &second));
+    ///
+    /// let third_rc = Arc::new(());
+    /// let third = Arc::downgrade(&third_rc);
+    /// assert!(!Weak::ptr_eq(&first, &third));
+    /// ```
+    #[inline]
+    #[unstable(feature = "weak_ptr_eq", issue = "55981")]
+    pub fn ptr_eq(this: &Self, other: &Self) -> bool {
+        this.ptr.as_ptr() == other.ptr.as_ptr()
+    }
 }
 
 #[stable(feature = "arc_weak", since = "1.4.0")]

src/libcore/macros.rs

@@ -238,6 +238,10 @@ macro_rules! debug_assert_ne {
 /// with converting downstream errors.
 ///
 /// The `?` operator was added to replace `try!` and should be used instead.
+/// Furthermore, `try` is a reserved word in Rust 2018, so if you must use
+/// it, you will need to use the [raw-identifier syntax][ris]: `r#try`.
+///
+/// [ris]: https://doc.rust-lang.org/nightly/rust-by-example/compatibility/raw_identifiers.html
 ///
 /// `try!` matches the given [`Result`]. In case of the `Ok` variant, the
 /// expression has the value of the wrapped value.

src/libcore/ptr.rs

@@ -2516,6 +2516,36 @@ pub fn eq<T: ?Sized>(a: *const T, b: *const T) -> bool {
     a == b
 }
 
+/// Hash the raw pointer address behind a reference, rather than the value
+/// it points to.
+///
+/// # Examples
+///
+/// ```
+/// #![feature(ptr_hash)]
+/// use std::collections::hash_map::DefaultHasher;
+/// use std::hash::{Hash, Hasher};
+/// use std::ptr;
+///
+/// let five = 5;
+/// let five_ref = &five;
+///
+/// let mut hasher = DefaultHasher::new();
+/// ptr::hash(five_ref, &mut hasher);
+/// let actual = hasher.finish();
+///
+/// let mut hasher = DefaultHasher::new();
+/// (five_ref as *const i32).hash(&mut hasher);
+/// let expected = hasher.finish();
+///
+/// assert_eq!(actual, expected);
+/// ```
+#[unstable(feature = "ptr_hash", reason = "newly added", issue = "56286")]
+pub fn hash<T, S: hash::Hasher>(hashee: *const T, into: &mut S) {
+    use hash::Hash;
+    hashee.hash(into);
+}
+
 // Impls for function pointers
 macro_rules! fnptr_impls_safety_abi {
     ($FnTy: ty, $($Arg: ident),*) => {

src/libcore/str/mod.rs

@@ -536,10 +536,9 @@ fn next_code_point_reverse<'a, I>(bytes: &mut I) -> Option<u32>
     where I: DoubleEndedIterator<Item = &'a u8>,
 {
     // Decode UTF-8
-    let w = match bytes.next_back() {
-        None => return None,
-        Some(&next_byte) if next_byte < 128 => return Some(next_byte as u32),
-        Some(&back_byte) => back_byte,
+    let w = match *bytes.next_back()? {
+        next_byte if next_byte < 128 => return Some(next_byte as u32),
+        back_byte => back_byte,
     };
 
     // Multibyte case follows

src/librustc/middle/dead.rs

@@ -166,6 +166,7 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
                     hir::ItemKind::Fn(..)
                     | hir::ItemKind::Ty(..)
                     | hir::ItemKind::Static(..)
+                    | hir::ItemKind::Existential(..)
                     | hir::ItemKind::Const(..) => {
                         intravisit::walk_item(self, &item);
                     }

src/librustc/middle/region.rs

@@ -592,10 +592,7 @@ impl<'tcx> ScopeTree {
                 return Some(scope.item_local_id());
             }
 
-            match self.opt_encl_scope(scope) {
-                None => return None,
-                Some(parent) => scope = parent,
-            }
+            scope = self.opt_encl_scope(scope)?;
         }
     }
 

src/librustc/session/search_paths.rs

@@ -67,14 +67,13 @@ impl<'a> Iterator for Iter<'a> {
 
     fn next(&mut self) -> Option<(&'a Path, PathKind)> {
         loop {
-            match self.iter.next() {
-                Some(&(kind, ref p)) if self.kind == PathKind::All ||
-                                        kind == PathKind::All ||
-                                        kind == self.kind => {
+            match *self.iter.next()? {
+                (kind, ref p) if self.kind == PathKind::All ||
+                                  kind == PathKind::All ||
+                                  kind == self.kind => {
                     return Some((p, kind))
                 }
-                Some(..) => {}
-                None => return None,
+                _ => {}
             }
         }
     }

src/librustc_borrowck/borrowck/check_loans.rs

@@ -615,7 +615,7 @@ impl<'a, 'tcx> CheckLoanCtxt<'a, 'tcx> {
                     let new_loan_str = &new_loan.kind.to_user_str();
                     self.bccx.cannot_reborrow_already_uniquely_borrowed(
                         new_loan.span, "closure", &nl, &new_loan_msg, new_loan_str,
-                        old_loan.span, &old_loan_msg, previous_end_span, Origin::Ast)
+                        old_loan.span, &old_loan_msg, previous_end_span, "", Origin::Ast)
                 }
                 (..) =>
                     self.bccx.cannot_reborrow_already_borrowed(

src/librustc_data_structures/lib.rs

@@ -81,7 +81,6 @@ pub mod sync;
 pub mod tiny_list;
 pub mod thin_vec;
 pub mod transitive_relation;
-pub mod tuple_slice;
 pub use ena::unify;
 pub mod vec_linked_list;
 pub mod work_queue;

src/librustc_incremental/persist/work_product.rs

@@ -29,7 +29,7 @@ pub fn copy_cgu_workproducts_to_incr_comp_cache_dir(
         return None
     }
 
-    let saved_files: Option<Vec<_>> =
+    let saved_files =
         files.iter()
              .map(|&(kind, ref path)| {
                  let extension = match kind {
@@ -51,11 +51,7 @@ pub fn copy_cgu_workproducts_to_incr_comp_cache_dir(
                      }
                  }
              })
-             .collect();
-    let saved_files = match saved_files {
-        None => return None,
-        Some(v) => v,
-    };
+             .collect::<Option<Vec<_>>>()?;
 
     let work_product = WorkProduct {
         cgu_name: cgu_name.to_string(),