Rollup of 10 pull requests

src/ci/azure-pipelines/auto.yml

@@ -273,7 +273,7 @@ jobs:
         MSYS_BITS: 32
         RUST_CONFIGURE_ARGS: --build=i686-pc-windows-gnu
         SCRIPT: make ci-subset-1
-        MINGW_URL: https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+        MINGW_URL: https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
         MINGW_ARCHIVE: i686-6.3.0-release-posix-dwarf-rt_v5-rev2.7z
         MINGW_DIR: mingw32
         # FIXME(#59637)
@@ -283,14 +283,14 @@ jobs:
         MSYS_BITS: 32
         RUST_CONFIGURE_ARGS: --build=i686-pc-windows-gnu
         SCRIPT: make ci-subset-2
-        MINGW_URL: https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+        MINGW_URL: https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
         MINGW_ARCHIVE: i686-6.3.0-release-posix-dwarf-rt_v5-rev2.7z
         MINGW_DIR: mingw32
       x86_64-mingw-1:
         MSYS_BITS: 64
         SCRIPT: make ci-subset-1
         RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-gnu
-        MINGW_URL: https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+        MINGW_URL: https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
         MINGW_ARCHIVE: x86_64-6.3.0-release-posix-seh-rt_v5-rev2.7z
         MINGW_DIR: mingw64
         # FIXME(#59637)
@@ -300,7 +300,7 @@ jobs:
         MSYS_BITS: 64
         SCRIPT: make ci-subset-2
         RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-gnu
-        MINGW_URL: https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+        MINGW_URL: https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
         MINGW_ARCHIVE: x86_64-6.3.0-release-posix-seh-rt_v5-rev2.7z
         MINGW_DIR: mingw64
 
@@ -327,7 +327,7 @@ jobs:
         MSYS_BITS: 32
         RUST_CONFIGURE_ARGS: --build=i686-pc-windows-gnu --enable-full-tools --enable-profiler
         SCRIPT: python x.py dist
-        MINGW_URL: https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+        MINGW_URL: https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
         MINGW_ARCHIVE: i686-6.3.0-release-posix-dwarf-rt_v5-rev2.7z
         MINGW_DIR: mingw32
         DIST_REQUIRE_ALL_TOOLS: 1
@@ -336,7 +336,7 @@ jobs:
         MSYS_BITS: 64
         SCRIPT: python x.py dist
         RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-gnu --enable-full-tools --enable-profiler
-        MINGW_URL: https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+        MINGW_URL: https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
         MINGW_ARCHIVE: x86_64-6.3.0-release-posix-seh-rt_v5-rev2.7z
         MINGW_DIR: mingw64
         DIST_REQUIRE_ALL_TOOLS: 1

src/ci/azure-pipelines/steps/install-clang.yml

@@ -36,7 +36,7 @@ steps:
     set -e
     mkdir -p citools
     cd citools
-    curl -f https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/LLVM-7.0.0-win64.tar.gz | tar xzf -
+    curl -f https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/LLVM-7.0.0-win64.tar.gz | tar xzf -
     echo "##vso[task.setvariable variable=RUST_CONFIGURE_ARGS]$RUST_CONFIGURE_ARGS --set llvm.clang-cl=`pwd`/clang-rust/bin/clang-cl.exe"
   condition: and(succeeded(), eq(variables['Agent.OS'], 'Windows_NT'), eq(variables['MINGW_URL'],''))
   displayName: Install clang (Windows)

src/ci/azure-pipelines/steps/install-sccache.yml

@@ -2,14 +2,14 @@ steps:
 
 - bash: |
     set -e
-    curl -fo /usr/local/bin/sccache https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2018-04-02-sccache-x86_64-apple-darwin
+    curl -fo /usr/local/bin/sccache https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2018-04-02-sccache-x86_64-apple-darwin
     chmod +x /usr/local/bin/sccache
   displayName: Install sccache (OSX)
   condition: and(succeeded(), eq(variables['Agent.OS'], 'Darwin'))
 
 - script: |
     md sccache
-    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf sccache\sccache.exe https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2018-04-26-sccache-x86_64-pc-windows-msvc"
+    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf sccache\sccache.exe https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2018-04-26-sccache-x86_64-pc-windows-msvc"
     echo ##vso[task.prependpath]%CD%\sccache
   displayName: Install sccache (Windows)
   condition: and(succeeded(), eq(variables['Agent.OS'], 'Windows_NT'))

src/ci/azure-pipelines/steps/install-windows-build-deps.yml

@@ -4,7 +4,7 @@ steps:
 # /~https://github.com/wixtoolset/wix3 originally
 - bash: |
     set -e
-    curl -O https://rust-lang-ci2.s3-us-west-1.amazonaws.com/rust-ci-mirror/wix311-binaries.zip
+    curl -O https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/wix311-binaries.zip
     echo "##vso[task.setvariable variable=WIX]`pwd`/wix"
     mkdir -p wix/bin
     cd wix/bin
@@ -18,7 +18,7 @@ steps:
 # one is MSI installers and one is EXE, but they're not used so frequently at
 # this point anyway so perhaps it's a wash!
 - script: |
-    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf is-install.exe https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2017-08-22-is.exe"
+    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf is-install.exe https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2017-08-22-is.exe"
     is-install.exe /VERYSILENT /SUPPRESSMSGBOXES /NORESTART /SP-
     echo ##vso[task.prependpath]C:\Program Files (x86)\Inno Setup 5
   displayName: Install InnoSetup
@@ -109,7 +109,7 @@ steps:
 # Note that this is originally from the github releases patch of Ninja
 - script: |
     md ninja
-    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf 2017-03-15-ninja-win.zip https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2017-03-15-ninja-win.zip"
+    powershell -Command "$ProgressPreference = 'SilentlyContinue'; iwr -outf 2017-03-15-ninja-win.zip https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2017-03-15-ninja-win.zip"
     7z x -oninja 2017-03-15-ninja-win.zip
     del 2017-03-15-ninja-win.zip
     set RUST_CONFIGURE_ARGS=%RUST_CONFIGURE_ARGS% --enable-ninja

src/ci/docker/armhf-gnu/Dockerfile

@@ -72,7 +72,7 @@ RUN arm-linux-gnueabihf-gcc addentropy.c -o rootfs/addentropy -static
 
 # TODO: What is this?!
 # Source of the file: /~https://github.com/vfdev-5/qemu-rpi2-vexpress/raw/master/vexpress-v2p-ca15-tc1.dtb
-RUN curl -O https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/vexpress-v2p-ca15-tc1.dtb
+RUN curl -O https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/vexpress-v2p-ca15-tc1.dtb
 
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh

src/ci/docker/dist-various-1/install-mips-musl.sh

@@ -5,7 +5,7 @@ mkdir /usr/local/mips-linux-musl
 # originally from
 # https://downloads.openwrt.org/snapshots/trunk/ar71xx/generic/
 # OpenWrt-Toolchain-ar71xx-generic_gcc-5.3.0_musl-1.1.16.Linux-x86_64.tar.bz2
-URL="https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror"
+URL="https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc"
 FILE="OpenWrt-Toolchain-ar71xx-generic_gcc-5.3.0_musl-1.1.16.Linux-x86_64.tar.bz2"
 curl -L "$URL/$FILE" | tar xjf - -C /usr/local/mips-linux-musl --strip-components=2
 

src/ci/docker/dist-various-2/build-wasi-toolchain.sh

@@ -5,7 +5,7 @@
 set -ex
 
 # Originally from https://releases.llvm.org/8.0.0/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04.tar.xz
-curl https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/clang%2Bllvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04.tar.xz | \
+curl https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/clang%2Bllvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04.tar.xz | \
   tar xJf -
 export PATH=`pwd`/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin:$PATH
 

src/ci/docker/dist-x86_64-linux/build-openssl.sh

@@ -4,7 +4,7 @@ set -ex
 source shared.sh
 
 VERSION=1.0.2k
-URL=https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/openssl-$VERSION.tar.gz
+URL=https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/openssl-$VERSION.tar.gz
 
 curl $URL | tar xzf -
 

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

@@ -25,7 +25,7 @@ cd netbsd
 
 mkdir -p /x-tools/x86_64-unknown-netbsd/sysroot
 
-URL=https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror
+URL=https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc
 
 # Originally from ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-$BSD/source/sets/*.tgz
 curl $URL/2018-03-01-netbsd-src.tgz | tar xzf -

src/ci/docker/scripts/android-sdk-manager.py

@@ -23,8 +23,9 @@
 HOST_OS = "linux"
 
 # Mirroring options
-MIRROR_BUCKET = "rust-lang-ci2"
-MIRROR_BASE_DIR = "rust-ci-mirror/android/"
+MIRROR_BUCKET = "rust-lang-ci-mirrors"
+MIRROR_BUCKET_REGION = "us-west-1"
+MIRROR_BASE_DIR = "rustc/android/"
 
 import argparse
 import hashlib
@@ -144,7 +145,8 @@ def cli_install(args):
     lockfile = Lockfile(args.lockfile)
     for package in lockfile.packages.values():
         # Download the file from the mirror into a temp file
-        url = "https://" + MIRROR_BUCKET + ".s3.amazonaws.com/" + MIRROR_BASE_DIR
+        url = "https://" + MIRROR_BUCKET + ".s3-" + MIRROR_BUCKET_REGION + \
+              ".amazonaws.com/" + MIRROR_BASE_DIR
         downloaded = package.download(url)
         # Extract the file in a temporary directory
         extract_dir = tempfile.mkdtemp()

src/ci/docker/scripts/freebsd-toolchain.sh

@@ -59,7 +59,7 @@ done
 
 # Originally downloaded from:
 # https://download.freebsd.org/ftp/releases/${freebsd_arch}/${freebsd_version}-RELEASE/base.txz
-URL=https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2019-04-04-freebsd-${freebsd_arch}-${freebsd_version}-RELEASE-base.txz
+URL=https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2019-04-04-freebsd-${freebsd_arch}-${freebsd_version}-RELEASE-base.txz
 curl "$URL" | tar xJf - -C "$sysroot" --wildcards "${files_to_extract[@]}"
 
 # Fix up absolute symlinks from the system image.  This can be removed

src/ci/docker/scripts/sccache.sh

@@ -1,6 +1,6 @@
 set -ex
 
 curl -fo /usr/local/bin/sccache \
-  https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2018-04-02-sccache-x86_64-unknown-linux-musl
+  https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2018-04-02-sccache-x86_64-unknown-linux-musl
 
 chmod +x /usr/local/bin/sccache

src/ci/install-awscli.sh

@@ -16,7 +16,7 @@
 set -euo pipefail
 IFS=$'\n\t'
 
-MIRROR="https://rust-lang-ci2.s3.amazonaws.com/rust-ci-mirror/2019-07-27-awscli.tar"
+MIRROR="https://rust-lang-ci-mirrors.s3-us-west-1.amazonaws.com/rustc/2019-07-27-awscli.tar"
 DEPS_DIR="/tmp/awscli-deps"
 
 pip="pip"

src/liballoc/collections/binary_heap.rs

@@ -1163,6 +1163,9 @@ impl<T> FusedIterator for Drain<'_, T> {}
 
 #[stable(feature = "binary_heap_extras_15", since = "1.5.0")]
 impl<T: Ord> From<Vec<T>> for BinaryHeap<T> {
+    /// Converts a `Vec<T>` into a `BinaryHeap<T>`.
+    ///
+    /// This conversion happens in-place, and has `O(n)` time complexity.
     fn from(vec: Vec<T>) -> BinaryHeap<T> {
         let mut heap = BinaryHeap { data: vec };
         heap.rebuild();

src/libcore/ascii.rs

@@ -14,6 +14,7 @@
 use crate::fmt;
 use crate::ops::Range;
 use crate::iter::FusedIterator;
+use crate::str::from_utf8_unchecked;
 
 /// An iterator over the escaped version of a byte.
 ///
@@ -22,6 +23,7 @@ use crate::iter::FusedIterator;
 ///
 /// [`escape_default`]: fn.escape_default.html
 #[stable(feature = "rust1", since = "1.0.0")]
+#[derive(Clone)]
 pub struct EscapeDefault {
     range: Range<usize>,
     data: [u8; 4],
@@ -130,6 +132,13 @@ impl ExactSizeIterator for EscapeDefault {}
 #[stable(feature = "fused", since = "1.26.0")]
 impl FusedIterator for EscapeDefault {}
 
+#[stable(feature = "ascii_escape_display", since = "1.39.0")]
+impl fmt::Display for EscapeDefault {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str(unsafe { from_utf8_unchecked(&self.data[self.range.clone()]) })
+    }
+}
+
 #[stable(feature = "std_debug", since = "1.16.0")]
 impl fmt::Debug for EscapeDefault {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

src/libcore/hash/mod.rs

@@ -553,8 +553,6 @@ impl<H> PartialEq for BuildHasherDefault<H> {
 #[stable(since = "1.29.0", feature = "build_hasher_eq")]
 impl<H> Eq for BuildHasherDefault<H> {}
 
-//////////////////////////////////////////////////////////////////////////////
-
 mod impls {
     use crate::mem;
     use crate::slice;

src/librustc_errors/diagnostic.rs

@@ -120,6 +120,9 @@ impl Diagnostic {
     }
 
     /// Adds a span/label to be included in the resulting snippet.
+    /// This label will be shown together with the original span/label used when creating the
+    /// diagnostic, *not* a span added by one of the `span_*` methods.
+    ///
     /// This is pushed onto the `MultiSpan` that was created when the
     /// diagnostic was first built. If you don't call this function at
     /// all, and you just supplied a `Span` to create the diagnostic,
@@ -196,6 +199,7 @@ impl Diagnostic {
         self
     }
 
+    /// Prints the span with a note above it.
     pub fn span_note<S: Into<MultiSpan>>(&mut self,
                                          sp: S,
                                          msg: &str)
@@ -209,6 +213,7 @@ impl Diagnostic {
         self
     }
 
+    /// Prints the span with a warn above it.
     pub fn span_warn<S: Into<MultiSpan>>(&mut self,
                                          sp: S,
                                          msg: &str)
@@ -222,6 +227,7 @@ impl Diagnostic {
         self
     }
 
+    /// Prints the span with some help above it.
     pub fn span_help<S: Into<MultiSpan>>(&mut self,
                                          sp: S,
                                          msg: &str)

src/librustc_mir/const_eval.rs

@@ -540,6 +540,12 @@ pub fn error_to_const_error<'mir, 'tcx>(
     ConstEvalErr { error: error.kind, stacktrace, span: ecx.tcx.span }
 }
 
+pub fn note_on_undefined_behavior_error() -> &'static str {
+    "The rules on what exactly is undefined behavior aren't clear, \
+    so this check might be overzealous. Please open an issue on the rust compiler \
+    repository if you believe it should not be considered undefined behavior"
+}
+
 fn validate_and_turn_into_const<'tcx>(
     tcx: TyCtxt<'tcx>,
     constant: RawConst<'tcx>,
@@ -579,10 +585,7 @@ fn validate_and_turn_into_const<'tcx>(
         let err = error_to_const_error(&ecx, error);
         match err.struct_error(ecx.tcx, "it is undefined behavior to use this value") {
             Ok(mut diag) => {
-                diag.note("The rules on what exactly is undefined behavior aren't clear, \
-                    so this check might be overzealous. Please open an issue on the rust compiler \
-                    repository if you believe it should not be considered undefined behavior",
-                );
+                diag.note(note_on_undefined_behavior_error());
                 diag.emit();
                 ErrorHandled::Reported
             }

src/librustc_mir/interpret/intern.rs

@@ -296,11 +296,7 @@ pub fn intern_const_alloc_recursive(
                 let err = crate::const_eval::error_to_const_error(&ecx, error);
                 match err.struct_error(ecx.tcx, "it is undefined behavior to use this value") {
                     Ok(mut diag) => {
-                        diag.note("The rules on what exactly is undefined behavior aren't clear, \
-                            so this check might be overzealous. Please open an issue on the rust \
-                            compiler repository if you believe it should not be considered \
-                            undefined behavior",
-                        );
+                        diag.note(crate::const_eval::note_on_undefined_behavior_error());
                         diag.emit();
                     }
                     Err(ErrorHandled::TooGeneric) |