Auto merge of #58866 - kennytm:rollup, r=kennytm

Rollup of 14 pull requests

Successful merges:

 - #58730 (Have all methods of Filter and FilterMap use internal iteration)
 - #58780 (ManuallyDrop != MaybeUninit)
 - #58782 (Replace `s` with `self` in docs for str methods taking self.)
 - #58785 (allow specifying attributes for tool lints)
 - #58802 (Ensure `record_layout_for_printing()` is inlined.)
 - #58821 (Fixed a syntax error in the pin docs)
 - #58830 (tidy: deny(rust_2018_idioms))
 - #58832 (Revert switching to GCP on AppVeyor)
 - #58833 (tools/rustbook: deny(rust_2018_idioms))
 - #58835 (tools/remote-test-{client,server}: deny(rust_2018_idioms))
 - #58838 (Fix typo in Vec#resize_with documentation)
 - #58842 (Forbid duplicating Cargo as a dependency)
 - #58852 (Update toolchain to build NetBSD release)
 - #58865 (Fix C-variadic function printing)

Author: bors

appveyor.yml

@@ -5,11 +5,6 @@ environment:
   # server goes down presumably. See #43333 for more info
   CARGO_HTTP_CHECK_REVOKE: false
 
-  # Execute the builds on GCE instead of Hyper-V. Those builders have a 3-4
-  # minute startup overhead, but AppVeyor support recommended this as a
-  # possible solution for #58160 (spurious 259 exit codes)
-  appveyor_build_worker_cloud: gce
-
   matrix:
   # 32/64 bit MSVC tests
   - MSYS_BITS: 64

src/ci/docker/dist-x86_64-netbsd/Dockerfile

@@ -3,23 +3,8 @@ FROM ubuntu:16.04
 COPY scripts/cross-apt-packages.sh /scripts/
 RUN sh /scripts/cross-apt-packages.sh
 
-# Ubuntu 16.04 (this container) ships with make 4, but something in the
-# toolchains we build below chokes on that, so go back to make 3
-COPY scripts/make3.sh /scripts/
-RUN sh /scripts/make3.sh
-
-COPY scripts/crosstool-ng.sh /scripts/
-RUN sh /scripts/crosstool-ng.sh
-
-COPY scripts/rustbuild-setup.sh /scripts/
-RUN sh /scripts/rustbuild-setup.sh
-USER rustbuild
-WORKDIR /tmp
-
 COPY dist-x86_64-netbsd/build-netbsd-toolchain.sh /tmp/
-RUN ./build-netbsd-toolchain.sh
-
-USER root
+RUN /tmp/build-netbsd-toolchain.sh
 
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
@@ -33,6 +18,5 @@ ENV \
 
 ENV HOSTS=x86_64-unknown-netbsd
 
-ENV RUST_CONFIGURE_ARGS --enable-extended --disable-docs \
-  --set llvm.allow-old-toolchain
+ENV RUST_CONFIGURE_ARGS --enable-extended --disable-docs
 ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS

src/ci/docker/dist-x86_64-netbsd/build-netbsd-toolchain.sh

@@ -28,15 +28,15 @@ mkdir -p /x-tools/x86_64-unknown-netbsd/sysroot
 URL=https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror
 
 # Originally from ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-$BSD/source/sets/*.tgz
-curl $URL/2017-03-17-netbsd-src.tgz | tar xzf -
-curl $URL/2017-03-17-netbsd-gnusrc.tgz | tar xzf -
-curl $URL/2017-03-17-netbsd-sharesrc.tgz | tar xzf -
-curl $URL/2017-03-17-netbsd-syssrc.tgz | tar xzf -
+curl $URL/2018-03-01-netbsd-src.tgz | tar xzf -
+curl $URL/2018-03-01-netbsd-gnusrc.tgz | tar xzf -
+curl $URL/2018-03-01-netbsd-sharesrc.tgz | tar xzf -
+curl $URL/2018-03-01-netbsd-syssrc.tgz | tar xzf -
 
 # Originally from ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-$BSD/amd64/binary/sets/*.tgz
-curl $URL/2017-03-17-netbsd-base.tgz | \
+curl $URL/2018-03-01-netbsd-base.tgz | \
   tar xzf - -C /x-tools/x86_64-unknown-netbsd/sysroot ./usr/include ./usr/lib ./lib
-curl $URL/2017-03-17-netbsd-comp.tgz | \
+curl $URL/2018-03-01-netbsd-comp.tgz | \
   tar xzf - -C /x-tools/x86_64-unknown-netbsd/sysroot ./usr/include ./usr/lib
 
 cd usr/src

src/liballoc/vec.rs

@@ -1260,7 +1260,7 @@ impl<T> Vec<T> {
     /// This method uses a closure to create new values on every push. If
     /// you'd rather [`Clone`] a given value, use [`resize`]. If you want
     /// to use the [`Default`] trait to generate values, you can pass
-    /// [`Default::default()`] as the second argument..
+    /// [`Default::default()`] as the second argument.
     ///
     /// # Examples
     ///

src/libcore/benches/iter.rs

@@ -185,13 +185,13 @@ bench_sums! {
 bench_sums! {
     bench_filter_sum,
     bench_filter_ref_sum,
-    (0i64..1000000).filter(|x| x % 2 == 0)
+    (0i64..1000000).filter(|x| x % 3 == 0)
 }
 
 bench_sums! {
     bench_filter_chain_sum,
     bench_filter_chain_ref_sum,
-    (0i64..1000000).chain(0..1000000).filter(|x| x % 2 == 0)
+    (0i64..1000000).chain(0..1000000).filter(|x| x % 3 == 0)
 }
 
 bench_sums! {
@@ -306,3 +306,31 @@ fn bench_skip_then_zip(b: &mut Bencher) {
         assert_eq!(s, 2009900);
     });
 }
+
+#[bench]
+fn bench_filter_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).map(black_box).filter(|x| x % 3 == 0).count()
+    })
+}
+
+#[bench]
+fn bench_filter_ref_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).map(black_box).by_ref().filter(|x| x % 3 == 0).count()
+    })
+}
+
+#[bench]
+fn bench_filter_chain_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).chain(0..1000000).map(black_box).filter(|x| x % 3 == 0).count()
+    })
+}
+
+#[bench]
+fn bench_filter_chain_ref_count(b: &mut Bencher) {
+    b.iter(|| {
+        (0i64..1000000).chain(0..1000000).map(black_box).by_ref().filter(|x| x % 3 == 0).count()
+    })
+}

src/libcore/iter/adapters/mod.rs

@@ -681,12 +681,7 @@ impl<I: Iterator, P> Iterator for Filter<I, P> where P: FnMut(&I::Item) -> bool
 
     #[inline]
     fn next(&mut self) -> Option<I::Item> {
-        for x in &mut self.iter {
-            if (self.predicate)(&x) {
-                return Some(x);
-            }
-        }
-        None
+        self.try_for_each(Err).err()
     }
 
     #[inline]
@@ -707,12 +702,9 @@ impl<I: Iterator, P> Iterator for Filter<I, P> where P: FnMut(&I::Item) -> bool
     // Using the branchless version will also simplify the LLVM byte code, thus
     // leaving more budget for LLVM optimizations.
     #[inline]
-    fn count(mut self) -> usize {
-        let mut count = 0;
-        for x in &mut self.iter {
-            count += (self.predicate)(&x) as usize;
-        }
-        count
+    fn count(self) -> usize {
+        let mut predicate = self.predicate;
+        self.iter.map(|x| predicate(&x) as usize).sum()
     }
 
     #[inline]
@@ -746,12 +738,7 @@ impl<I: DoubleEndedIterator, P> DoubleEndedIterator for Filter<I, P>
 {
     #[inline]
     fn next_back(&mut self) -> Option<I::Item> {
-        for x in self.iter.by_ref().rev() {
-            if (self.predicate)(&x) {
-                return Some(x);
-            }
-        }
-        None
+        self.try_rfold((), |_, x| Err(x)).err()
     }
 
     #[inline]
@@ -820,12 +807,7 @@ impl<B, I: Iterator, F> Iterator for FilterMap<I, F>
 
     #[inline]
     fn next(&mut self) -> Option<B> {
-        for x in self.iter.by_ref() {
-            if let Some(y) = (self.f)(x) {
-                return Some(y);
-            }
-        }
-        None
+        self.try_for_each(Err).err()
     }
 
     #[inline]
@@ -863,12 +845,7 @@ impl<B, I: DoubleEndedIterator, F> DoubleEndedIterator for FilterMap<I, F>
 {
     #[inline]
     fn next_back(&mut self) -> Option<B> {
-        for x in self.iter.by_ref().rev() {
-            if let Some(y) = (self.f)(x) {
-                return Some(y);
-            }
-        }
-        None
+        self.try_rfold((), |_, x| Err(x)).err()
     }
 
     #[inline]

src/libcore/mem.rs

@@ -900,10 +900,16 @@ pub fn discriminant<T>(v: &T) -> Discriminant<T> {
     }
 }
 
+// FIXME: Reference `MaybeUninit` from these docs, once that is stable.
 /// A wrapper to inhibit compiler from automatically calling `T`’s destructor.
 ///
 /// This wrapper is 0-cost.
 ///
+/// `ManuallyDrop<T>` is subject to the same layout optimizations as `T`.
+/// As a consequence, it has *no effect* on the assumptions that the compiler makes
+/// about all values being initialized at their type.  In particular, initializing
+/// a `ManuallyDrop<&mut T>` with [`mem::zeroed`] is undefined behavior.
+///
 /// # Examples
 ///
 /// This wrapper helps with explicitly documenting the drop order dependencies between fields of
@@ -935,6 +941,8 @@ pub fn discriminant<T>(v: &T) -> Discriminant<T> {
 ///     }
 /// }
 /// ```
+///
+/// [`mem::zeroed`]: fn.zeroed.html
 #[stable(feature = "manually_drop", since = "1.20.0")]
 #[lang = "manually_drop"]
 #[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]

src/libcore/pin.rs

@@ -215,7 +215,7 @@
 //!     had a method `fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut T>`.
 //!     Then we could do the following:
 //!     ```compile_fail
-//!     fn exploit_ref_cell<T>(rc: Pin<&mut RefCell<T>) {
+//!     fn exploit_ref_cell<T>(rc: Pin<&mut RefCell<T>>) {
 //!         { let p = rc.as_mut().get_pin_mut(); } // Here we get pinned access to the `T`.
 //!         let rc_shr: &RefCell<T> = rc.into_ref().get_ref();
 //!         let b = rc_shr.borrow_mut();

src/libcore/str/mod.rs

@@ -3965,7 +3965,7 @@ impl str {
         me.make_ascii_lowercase()
     }
 
-    /// Return an iterator that escapes each char in `s` with [`char::escape_debug`].
+    /// Return an iterator that escapes each char in `self` with [`char::escape_debug`].
     ///
     /// Note: only extended grapheme codepoints that begin the string will be
     /// escaped.
@@ -4013,7 +4013,7 @@ impl str {
         }
     }
 
-    /// Return an iterator that escapes each char in `s` with [`char::escape_default`].
+    /// Return an iterator that escapes each char in `self` with [`char::escape_default`].
     ///
     /// [`char::escape_default`]: ../std/primitive.char.html#method.escape_default
     ///
@@ -4051,7 +4051,7 @@ impl str {
         EscapeDefault { inner: self.chars().flat_map(CharEscapeDefault) }
     }
 
-    /// Return an iterator that escapes each char in `s` with [`char::escape_unicode`].
+    /// Return an iterator that escapes each char in `self` with [`char::escape_unicode`].
     ///
     /// [`char::escape_unicode`]: ../std/primitive.char.html#method.escape_unicode
     ///

src/librustc/lint/mod.rs

@@ -132,14 +132,22 @@ macro_rules! declare_lint {
 
 #[macro_export]
 macro_rules! declare_tool_lint {
-    ($vis: vis $tool: ident ::$NAME: ident, $Level: ident, $desc: expr) => (
-        declare_tool_lint!{$vis $tool::$NAME, $Level, $desc, false}
+    (
+        $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level: ident, $desc: expr
+    ) => (
+        declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, false}
     );
-    ($vis: vis $tool: ident ::$NAME: ident, $Level: ident, $desc: expr,
-     report_in_external_macro: $rep: expr) => (
-         declare_tool_lint!{$vis $tool::$NAME, $Level, $desc, $rep}
+    (
+        $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
+        report_in_external_macro: $rep:expr
+    ) => (
+         declare_tool_lint!{$(#[$attr])* $vis $tool::$NAME, $Level, $desc, $rep}
     );
-    ($vis: vis $tool: ident ::$NAME: ident, $Level: ident, $desc: expr, $external: expr) => (
+    (
+        $(#[$attr:meta])* $vis:vis $tool:ident ::$NAME:ident, $Level:ident, $desc:expr,
+        $external:expr
+    ) => (
+        $(#[$attr])*
         $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
             name: &concat!(stringify!($tool), "::", stringify!($NAME)),
             default_level: $crate::lint::$Level,