Rollup of 13 pull requests

RELEASES.md

@@ -140,6 +140,29 @@ Compatibility Notes
 [`{Any + Send + Sync}::downcast_ref`]: https://doc.rust-lang.org/std/any/trait.Any.html#method.downcast_ref-2
 [`{Any + Send + Sync}::is`]: https://doc.rust-lang.org/std/any/trait.Any.html#method.is-2
 
+Version 1.27.1 (2018-07-10)
+===========================
+
+Security Notes
+--------------
+
+- rustdoc would execute plugins in the /tmp/rustdoc/plugins directory
+  when running, which enabled executing code as some other user on a
+  given machine. This release fixes that vulnerability; you can read
+  more about this on the [blog][rustdoc-sec]. The associated CVE is [CVE-2018-1000622].
+
+  Thank you to Red Hat for responsibily disclosing this vulnerability to us.
+
+Compatibility Notes
+-------------------
+
+- The borrow checker was fixed to avoid an additional potential unsoundness when using
+  match ergonomics: [#51415][51415], [#49534][49534].
+
+[51415]: https://github.com/rust-lang/rust/issues/51415
+[49534]: https://github.com/rust-lang/rust/issues/49534
+[rustdoc-sec]: https://blog.rust-lang.org/2018/07/06/security-advisory-for-rustdoc.html
+[CVE-2018-1000622]: https://cve.mitre.org/cgi-bin/cvename.cgi?name=%20CVE-2018-1000622
 
 Version 1.27.0 (2018-06-21)
 ==========================

src/bootstrap/lib.rs

@@ -206,7 +206,8 @@ const LLVM_TOOLS: &[&str] = &[
     "llvm-objcopy", // used to transform ELFs into binary format which flashing tools consume
     "llvm-objdump", // used to disassemble programs
     "llvm-profdata", // used to inspect and merge files generated by profiles
-    "llvm-size", // prints the size of the linker sections of a program
+    "llvm-size", // used to prints the size of the linker sections of a program
+    "llvm-strip", // used to discard symbols from binary files to reduce their size
 ];
 
 /// A structure representing a Rust compiler.

src/build_helper/lib.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![deny(bare_trait_objects)]
+
 use std::fs::File;
 use std::path::{Path, PathBuf};
 use std::process::{Command, Stdio};

src/liballoc_jemalloc/lib.rs

@@ -10,6 +10,7 @@
 
 #![no_std]
 #![allow(unused_attributes)]
+#![deny(bare_trait_objects)]
 #![unstable(feature = "alloc_jemalloc",
             reason = "implementation detail of std, does not provide any public API",
             issue = "0")]

src/liballoc_system/lib.rs

@@ -10,6 +10,7 @@
 
 #![no_std]
 #![allow(unused_attributes)]
+#![deny(bare_trait_objects)]
 #![unstable(feature = "alloc_system",
             reason = "this library is unlikely to be stabilized in its current \
                       form or name",

src/libarena/lib.rs

@@ -30,6 +30,7 @@
 #![cfg_attr(test, feature(test))]
 
 #![allow(deprecated)]
+#![deny(bare_trait_objects)]
 
 extern crate alloc;
 extern crate rustc_data_structures;

src/libcore/iter/mod.rs

@@ -787,17 +787,19 @@ where
     #[inline]
     fn spec_next(&mut self) -> Option<Self::Item> {
         self.first_take = false;
-        if !(self.iter.start <= self.iter.end) {
+        if self.iter.is_empty() {
+            self.iter.is_iterating = Some(false);
             return None;
         }
         // add 1 to self.step to get original step size back
         // it was decremented for the general case on construction
         if let Some(n) = self.iter.start.add_usize(self.step+1) {
+            self.iter.is_iterating = Some(n <= self.iter.end);
             let next = mem::replace(&mut self.iter.start, n);
             Some(next)
         } else {
-            let last = self.iter.start.replace_one();
-            self.iter.end.replace_zero();
+            let last = self.iter.start.clone();
+            self.iter.is_iterating = Some(false);
             Some(last)
         }
     }

src/libcore/iter/range.rs

@@ -10,7 +10,7 @@
 
 use convert::TryFrom;
 use mem;
-use ops::{self, Add, Sub, Try};
+use ops::{self, Add, Sub};
 use usize;
 
 use super::{FusedIterator, TrustedLen};
@@ -330,23 +330,23 @@ impl<A: Step> Iterator for ops::RangeInclusive<A> {
 
     #[inline]
     fn next(&mut self) -> Option<A> {
-        if self.start <= self.end {
-            if self.start < self.end {
-                let n = self.start.add_one();
-                Some(mem::replace(&mut self.start, n))
-            } else {
-                let last = self.start.replace_one();
-                self.end.replace_zero();
-                Some(last)
-            }
+        if self.is_empty() {
+            self.is_iterating = Some(false);
+            return None;
+        }
+        if self.start < self.end {
+            let n = self.start.add_one();
+            self.is_iterating = Some(true);
+            Some(mem::replace(&mut self.start, n))
         } else {
-            None
+            self.is_iterating = Some(false);
+            Some(self.start.clone())
         }
     }
 
     #[inline]
     fn size_hint(&self) -> (usize, Option<usize>) {
-        if !(self.start <= self.end) {
+        if self.is_empty() {
             return (0, Some(0));
         }
 
@@ -358,25 +358,29 @@ impl<A: Step> Iterator for ops::RangeInclusive<A> {
 
     #[inline]
     fn nth(&mut self, n: usize) -> Option<A> {
+        if self.is_empty() {
+            self.is_iterating = Some(false);
+            return None;
+        }
+
         if let Some(plus_n) = self.start.add_usize(n) {
             use cmp::Ordering::*;
 
             match plus_n.partial_cmp(&self.end) {
                 Some(Less) => {
+                    self.is_iterating = Some(true);
                     self.start = plus_n.add_one();
                     return Some(plus_n)
                 }
                 Some(Equal) => {
-                    self.start.replace_one();
-                    self.end.replace_zero();
+                    self.is_iterating = Some(false);
                     return Some(plus_n)
                 }
                 _ => {}
             }
         }
 
-        self.start.replace_one();
-        self.end.replace_zero();
+        self.is_iterating = Some(false);
         None
     }
 
@@ -394,68 +398,24 @@ impl<A: Step> Iterator for ops::RangeInclusive<A> {
     fn max(mut self) -> Option<A> {
         self.next_back()
     }
-
-    #[inline]
-    fn try_fold<B, F, R>(&mut self, init: B, mut f: F) -> R where
-        Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Ok=B>
-    {
-        let mut accum = init;
-        if self.start <= self.end {
-            loop {
-                let (x, done) =
-                    if self.start < self.end {
-                        let n = self.start.add_one();
-                        (mem::replace(&mut self.start, n), false)
-                    } else {
-                        self.end.replace_zero();
-                        (self.start.replace_one(), true)
-                    };
-                accum = f(accum, x)?;
-                if done { break }
-            }
-        }
-        Try::from_ok(accum)
-    }
 }
 
 #[stable(feature = "inclusive_range", since = "1.26.0")]
 impl<A: Step> DoubleEndedIterator for ops::RangeInclusive<A> {
     #[inline]
     fn next_back(&mut self) -> Option<A> {
-        if self.start <= self.end {
-            if self.start < self.end {
-                let n = self.end.sub_one();
-                Some(mem::replace(&mut self.end, n))
-            } else {
-                let last = self.end.replace_zero();
-                self.start.replace_one();
-                Some(last)
-            }
-        } else {
-            None
+        if self.is_empty() {
+            self.is_iterating = Some(false);
+            return None;
         }
-    }
-
-    #[inline]
-    fn try_rfold<B, F, R>(&mut self, init: B, mut f: F) -> R where
-        Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Ok=B>
-    {
-        let mut accum = init;
-        if self.start <= self.end {
-            loop {
-                let (x, done) =
-                    if self.start < self.end {
-                        let n = self.end.sub_one();
-                        (mem::replace(&mut self.end, n), false)
-                    } else {
-                        self.start.replace_one();
-                        (self.end.replace_zero(), true)
-                    };
-                accum = f(accum, x)?;
-                if done { break }
-            }
+        if self.start < self.end {
+            let n = self.end.sub_one();
+            self.is_iterating = Some(true);
+            Some(mem::replace(&mut self.end, n))
+        } else {
+            self.is_iterating = Some(false);
+            Some(self.end.clone())
         }
-        Try::from_ok(accum)
     }
 }
 

src/libcore/ops/range.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 use fmt;
+use hash::{Hash, Hasher};
 
 /// An unbounded range (`..`).
 ///
@@ -326,15 +327,56 @@ impl<Idx: PartialOrd<Idx>> RangeTo<Idx> {
 /// assert_eq!(arr[1..=2], [  1,2  ]);  // RangeInclusive
 /// ```
 #[doc(alias = "..=")]
-#[derive(Clone, PartialEq, Eq, Hash)]  // not Copy -- see #27186
+#[derive(Clone)]  // not Copy -- see #27186
 #[stable(feature = "inclusive_range", since = "1.26.0")]
 pub struct RangeInclusive<Idx> {
-    // FIXME: The current representation follows RFC 1980,
-    // but it is known that LLVM is not able to optimize loops following that RFC.
-    // Consider adding an extra `bool` field to indicate emptiness of the range.
-    // See #45222 for performance test cases.
     pub(crate) start: Idx,
     pub(crate) end: Idx,
+    pub(crate) is_iterating: Option<bool>,
+    // This field is:
+    //  - `None` when next() or next_back() was never called
+    //  - `Some(true)` when `start <= end` assuming no overflow
+    //  - `Some(false)` otherwise
+    // The field cannot be a simple `bool` because the `..=` constructor can
+    // accept non-PartialOrd types, also we want the constructor to be const.
+}
+
+trait RangeInclusiveEquality: Sized {
+    fn canonicalized_is_empty(range: &RangeInclusive<Self>) -> bool;
+}
+impl<T> RangeInclusiveEquality for T {
+    #[inline]
+    default fn canonicalized_is_empty(range: &RangeInclusive<Self>) -> bool {
+        !range.is_iterating.unwrap_or(false)
+    }
+}
+impl<T: PartialOrd> RangeInclusiveEquality for T {
+    #[inline]
+    fn canonicalized_is_empty(range: &RangeInclusive<Self>) -> bool {
+        range.is_empty()
+    }
+}
+
+#[stable(feature = "inclusive_range", since = "1.26.0")]
+impl<Idx: PartialEq> PartialEq for RangeInclusive<Idx> {
+    #[inline]
+    fn eq(&self, other: &Self) -> bool {
+        self.start == other.start && self.end == other.end
+            && RangeInclusiveEquality::canonicalized_is_empty(self)
+                == RangeInclusiveEquality::canonicalized_is_empty(other)
+    }
+}
+
+#[stable(feature = "inclusive_range", since = "1.26.0")]
+impl<Idx: Eq> Eq for RangeInclusive<Idx> {}
+
+#[stable(feature = "inclusive_range", since = "1.26.0")]
+impl<Idx: Hash> Hash for RangeInclusive<Idx> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.start.hash(state);
+        self.end.hash(state);
+        RangeInclusiveEquality::canonicalized_is_empty(self).hash(state);
+    }
 }
 
 impl<Idx> RangeInclusive<Idx> {
@@ -350,7 +392,7 @@ impl<Idx> RangeInclusive<Idx> {
     #[stable(feature = "inclusive_range_methods", since = "1.27.0")]
     #[inline]
     pub const fn new(start: Idx, end: Idx) -> Self {
-        Self { start, end }
+        Self { start, end, is_iterating: None }
     }
 
     /// Returns the lower bound of the range (inclusive).
@@ -492,8 +534,9 @@ impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
     /// assert!(r.is_empty());
     /// ```
     #[unstable(feature = "range_is_empty", reason = "recently added", issue = "48111")]
+    #[inline]
     pub fn is_empty(&self) -> bool {
-        !(self.start <= self.end)
+        !self.is_iterating.unwrap_or_else(|| self.start <= self.end)
     }
 }
 

src/libcore/option.rs

@@ -845,6 +845,33 @@ impl<T> Option<T> {
     pub fn take(&mut self) -> Option<T> {
         mem::replace(self, None)
     }
+
+    /// Replaces the actual value in the option by the value given in parameter,
+    /// returning the old value if present,
+    /// leaving a [`Some`] in its place without deinitializing either one.
+    ///
+    /// [`Some`]: #variant.Some
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(option_replace)]
+    ///
+    /// let mut x = Some(2);
+    /// let old = x.replace(5);
+    /// assert_eq!(x, Some(5));
+    /// assert_eq!(old, Some(2));
+    ///
+    /// let mut x = None;
+    /// let old = x.replace(3);
+    /// assert_eq!(x, Some(3));
+    /// assert_eq!(old, None);
+    /// ```
+    #[inline]
+    #[unstable(feature = "option_replace", issue = "51998")]
+    pub fn replace(&mut self, value: T) -> Option<T> {
+        mem::replace(self, Some(value))
+    }
 }
 
 impl<'a, T: Clone> Option<&'a T> {