Auto merge of #73563 - Manishearth:rollup-oowgwwm, r=Manishearth

Rollup of 9 pull requests

Successful merges:

 - #72456 (Try to suggest dereferences on trait selection failed)
 - #72788 (Projection bound validation)
 - #72790 (core/time: Add Duration methods for zero)
 - #73227 (Allow multiple `asm!` options groups and report an error on duplicate options)
 - #73287 (lint: normalize projections using opaque types)
 - #73291 (Pre-compute `LocalDefId` <-> `HirId` mappings and remove `NodeId` <-> `HirId` conversion APIs)
 - #73378 (Remove use of specialization from librustc_arena)
 - #73411 (Update bootstrap to rustc 1.45.0-beta.2 (1dc0f6d 2020-06-15))
 - #73443 (ci: allow gating GHA on everything but macOS)

Failed merges:

r? @ghost

Author: bors

Diff for: .github/workflows/ci.yml

@@ -369,35 +369,6 @@ jobs:
             env:
               DEPLOY_TOOLSTATES_JSON: toolstates-linux.json
             os: ubuntu-latest-xl
-          - name: dist-x86_64-apple
-            env:
-              SCRIPT: "./x.py dist"
-              RUST_CONFIGURE_ARGS: "--target=aarch64-apple-ios,x86_64-apple-ios --enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc"
-              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
-              MACOSX_DEPLOYMENT_TARGET: 10.7
-              NO_LLVM_ASSERTIONS: 1
-              NO_DEBUG_ASSERTIONS: 1
-              DIST_REQUIRE_ALL_TOOLS: 1
-            os: macos-latest
-          - name: dist-x86_64-apple-alt
-            env:
-              SCRIPT: "./x.py dist"
-              RUST_CONFIGURE_ARGS: "--enable-extended --enable-profiler --set rust.jemalloc"
-              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
-              MACOSX_DEPLOYMENT_TARGET: 10.7
-              NO_LLVM_ASSERTIONS: 1
-              NO_DEBUG_ASSERTIONS: 1
-            os: macos-latest
-          - name: x86_64-apple
-            env:
-              SCRIPT: "./x.py test"
-              RUST_CONFIGURE_ARGS: "--build=x86_64-apple-darwin --enable-sanitizers --enable-profiler --set rust.jemalloc"
-              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
-              MACOSX_DEPLOYMENT_TARGET: 10.8
-              MACOSX_STD_DEPLOYMENT_TARGET: 10.7
-              NO_LLVM_ASSERTIONS: 1
-              NO_DEBUG_ASSERTIONS: 1
-            os: macos-latest
           - name: x86_64-msvc-1
             env:
               RUST_CONFIGURE_ARGS: "--build=x86_64-pc-windows-msvc --enable-profiler"
@@ -580,6 +551,135 @@ jobs:
           AWS_ACCESS_KEY_ID: "${{ env.ARTIFACTS_AWS_ACCESS_KEY_ID }}"
           AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.ARTIFACTS_AWS_ACCESS_KEY_ID)] }}"
         if: "success() && !env.SKIP_JOB && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')"
+  auto-fallible:
+    name: auto-fallible
+    env:
+      CI_JOB_NAME: "${{ matrix.name }}"
+      SCCACHE_BUCKET: rust-lang-gha-caches
+      DEPLOY_BUCKET: rust-lang-gha
+      TOOLSTATE_REPO: "https://github.com/pietroalbini/rust-toolstate"
+      TOOLSTATE_ISSUES_API_URL: "https://api.github.com/repos/pietroalbini/rust-toolstate/issues"
+      TOOLSTATE_PUBLISH: 1
+      CACHES_AWS_ACCESS_KEY_ID: AKIA46X5W6CZOMUQATD5
+      ARTIFACTS_AWS_ACCESS_KEY_ID: AKIA46X5W6CZH5AYXDVF
+      CACHE_DOMAIN: ci-caches-gha.rust-lang.org
+    if: "github.event_name == 'push' && github.ref == 'refs/heads/auto' && github.repository == 'rust-lang-ci/rust'"
+    strategy:
+      matrix:
+        include:
+          - name: dist-x86_64-apple
+            env:
+              SCRIPT: "./x.py dist"
+              RUST_CONFIGURE_ARGS: "--target=aarch64-apple-ios,x86_64-apple-ios --enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc"
+              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+              MACOSX_DEPLOYMENT_TARGET: 10.7
+              NO_LLVM_ASSERTIONS: 1
+              NO_DEBUG_ASSERTIONS: 1
+              DIST_REQUIRE_ALL_TOOLS: 1
+            os: macos-latest
+          - name: dist-x86_64-apple-alt
+            env:
+              SCRIPT: "./x.py dist"
+              RUST_CONFIGURE_ARGS: "--enable-extended --enable-profiler --set rust.jemalloc"
+              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+              MACOSX_DEPLOYMENT_TARGET: 10.7
+              NO_LLVM_ASSERTIONS: 1
+              NO_DEBUG_ASSERTIONS: 1
+            os: macos-latest
+          - name: x86_64-apple
+            env:
+              SCRIPT: "./x.py test"
+              RUST_CONFIGURE_ARGS: "--build=x86_64-apple-darwin --enable-sanitizers --enable-profiler --set rust.jemalloc"
+              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+              MACOSX_DEPLOYMENT_TARGET: 10.8
+              MACOSX_STD_DEPLOYMENT_TARGET: 10.7
+              NO_LLVM_ASSERTIONS: 1
+              NO_DEBUG_ASSERTIONS: 1
+            os: macos-latest
+    timeout-minutes: 600
+    runs-on: "${{ matrix.os }}"
+    steps:
+      - name: disable git crlf conversion
+        run: git config --global core.autocrlf false
+        shell: bash
+      - name: checkout the source code
+        uses: actions/checkout@v1
+        with:
+          fetch-depth: 2
+      - name: configure GitHub Actions to kill the build when outdated
+        uses: rust-lang/simpleinfra/github-actions/cancel-outdated-builds@master
+        with:
+          github_token: "${{ secrets.github_token }}"
+        if: "success() && !env.SKIP_JOB && github.ref != 'refs/heads/try'"
+      - name: add extra environment variables
+        run: src/ci/scripts/setup-environment.sh
+        env:
+          EXTRA_VARIABLES: "${{ toJson(matrix.env) }}"
+        if: success() && !env.SKIP_JOB
+      - name: decide whether to skip this job
+        run: src/ci/scripts/should-skip-this.sh
+        if: success() && !env.SKIP_JOB
+      - name: collect CPU statistics
+        run: src/ci/scripts/collect-cpu-stats.sh
+        if: success() && !env.SKIP_JOB
+      - name: show the current environment
+        run: src/ci/scripts/dump-environment.sh
+        if: success() && !env.SKIP_JOB
+      - name: install awscli
+        run: src/ci/scripts/install-awscli.sh
+        if: success() && !env.SKIP_JOB
+      - name: install sccache
+        run: src/ci/scripts/install-sccache.sh
+        if: success() && !env.SKIP_JOB
+      - name: install clang
+        run: src/ci/scripts/install-clang.sh
+        if: success() && !env.SKIP_JOB
+      - name: install WIX
+        run: src/ci/scripts/install-wix.sh
+        if: success() && !env.SKIP_JOB
+      - name: install InnoSetup
+        run: src/ci/scripts/install-innosetup.sh
+        if: success() && !env.SKIP_JOB
+      - name: ensure the build happens on a partition with enough space
+        run: src/ci/scripts/symlink-build-dir.sh
+        if: success() && !env.SKIP_JOB
+      - name: disable git crlf conversion
+        run: src/ci/scripts/disable-git-crlf-conversion.sh
+        if: success() && !env.SKIP_JOB
+      - name: install MSYS2
+        run: src/ci/scripts/install-msys2.sh
+        if: success() && !env.SKIP_JOB
+      - name: install MinGW
+        run: src/ci/scripts/install-mingw.sh
+        if: success() && !env.SKIP_JOB
+      - name: install ninja
+        run: src/ci/scripts/install-ninja.sh
+        if: success() && !env.SKIP_JOB
+      - name: enable ipv6 on Docker
+        run: src/ci/scripts/enable-docker-ipv6.sh
+        if: success() && !env.SKIP_JOB
+      - name: disable git crlf conversion
+        run: src/ci/scripts/disable-git-crlf-conversion.sh
+        if: success() && !env.SKIP_JOB
+      - name: checkout submodules
+        run: src/ci/scripts/checkout-submodules.sh
+        if: success() && !env.SKIP_JOB
+      - name: ensure line endings are correct
+        run: src/ci/scripts/verify-line-endings.sh
+        if: success() && !env.SKIP_JOB
+      - name: run the build
+        run: src/ci/scripts/run-build-from-ci.sh
+        env:
+          AWS_ACCESS_KEY_ID: "${{ env.CACHES_AWS_ACCESS_KEY_ID }}"
+          AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.CACHES_AWS_ACCESS_KEY_ID)] }}"
+          TOOLSTATE_REPO_ACCESS_TOKEN: "${{ secrets.TOOLSTATE_REPO_ACCESS_TOKEN }}"
+        if: success() && !env.SKIP_JOB
+      - name: upload artifacts to S3
+        run: src/ci/scripts/upload-artifacts.sh
+        env:
+          AWS_ACCESS_KEY_ID: "${{ env.ARTIFACTS_AWS_ACCESS_KEY_ID }}"
+          AWS_SECRET_ACCESS_KEY: "${{ secrets[format('AWS_SECRET_ACCESS_KEY_{0}', env.ARTIFACTS_AWS_ACCESS_KEY_ID)] }}"
+        if: "success() && !env.SKIP_JOB && (github.event_name == 'push' || env.DEPLOY == '1' || env.DEPLOY_ALT == '1')"
   master:
     name: master
     runs-on: ubuntu-latest

Diff for: src/ci/github-actions/ci.yml

@@ -414,42 +414,6 @@ jobs:
               DEPLOY_TOOLSTATES_JSON: toolstates-linux.json
             <<: *job-linux-xl
 
-          ####################
-          #  macOS Builders  #
-          ####################
-
-          - name: dist-x86_64-apple
-            env:
-              SCRIPT: ./x.py dist
-              RUST_CONFIGURE_ARGS: --target=aarch64-apple-ios,x86_64-apple-ios --enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc
-              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
-              MACOSX_DEPLOYMENT_TARGET: 10.7
-              NO_LLVM_ASSERTIONS: 1
-              NO_DEBUG_ASSERTIONS: 1
-              DIST_REQUIRE_ALL_TOOLS: 1
-            <<: *job-macos-xl
-
-          - name: dist-x86_64-apple-alt
-            env:
-              SCRIPT: ./x.py dist
-              RUST_CONFIGURE_ARGS: --enable-extended --enable-profiler --set rust.jemalloc
-              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
-              MACOSX_DEPLOYMENT_TARGET: 10.7
-              NO_LLVM_ASSERTIONS: 1
-              NO_DEBUG_ASSERTIONS: 1
-            <<: *job-macos-xl
-
-          - name: x86_64-apple
-            env:
-              SCRIPT: ./x.py test
-              RUST_CONFIGURE_ARGS: --build=x86_64-apple-darwin --enable-sanitizers --enable-profiler --set rust.jemalloc
-              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
-              MACOSX_DEPLOYMENT_TARGET: 10.8
-              MACOSX_STD_DEPLOYMENT_TARGET: 10.7
-              NO_LLVM_ASSERTIONS: 1
-              NO_DEBUG_ASSERTIONS: 1
-            <<: *job-macos-xl
-
           ######################
           #  Windows Builders  #
           ######################
@@ -595,6 +559,51 @@ jobs:
               SCRIPT: python x.py dist
             <<: *job-windows-xl
 
+  auto-fallible:
+    <<: *base-ci-job
+    name: auto-fallible
+    env:
+      <<: [*shared-ci-variables, *prod-variables]
+    if: github.event_name == 'push' && github.ref == 'refs/heads/auto' && github.repository == 'rust-lang-ci/rust'
+    strategy:
+      matrix:
+        include:
+          ####################
+          #  macOS Builders  #
+          ####################
+
+          - name: dist-x86_64-apple
+            env:
+              SCRIPT: ./x.py dist
+              RUST_CONFIGURE_ARGS: --target=aarch64-apple-ios,x86_64-apple-ios --enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc
+              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+              MACOSX_DEPLOYMENT_TARGET: 10.7
+              NO_LLVM_ASSERTIONS: 1
+              NO_DEBUG_ASSERTIONS: 1
+              DIST_REQUIRE_ALL_TOOLS: 1
+            <<: *job-macos-xl
+
+          - name: dist-x86_64-apple-alt
+            env:
+              SCRIPT: ./x.py dist
+              RUST_CONFIGURE_ARGS: --enable-extended --enable-profiler --set rust.jemalloc
+              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+              MACOSX_DEPLOYMENT_TARGET: 10.7
+              NO_LLVM_ASSERTIONS: 1
+              NO_DEBUG_ASSERTIONS: 1
+            <<: *job-macos-xl
+
+          - name: x86_64-apple
+            env:
+              SCRIPT: ./x.py test
+              RUST_CONFIGURE_ARGS: --build=x86_64-apple-darwin --enable-sanitizers --enable-profiler --set rust.jemalloc
+              RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+              MACOSX_DEPLOYMENT_TARGET: 10.8
+              MACOSX_STD_DEPLOYMENT_TARGET: 10.7
+              NO_LLVM_ASSERTIONS: 1
+              NO_DEBUG_ASSERTIONS: 1
+            <<: *job-macos-xl
+
   master:
     name: master
     runs-on: ubuntu-latest

Diff for: src/libcore/result.rs

@@ -1155,6 +1155,7 @@ impl<T: Deref, E> Result<T, E> {
     /// # Examples
     ///
     /// ```
+    /// #![feature(inner_deref)]
     /// let x: Result<String, u32> = Ok("hello".to_string());
     /// let y: Result<&str, &u32> = Ok("hello");
     /// assert_eq!(x.as_deref(), y);
@@ -1189,12 +1190,15 @@ impl<T: DerefMut, E> Result<T, E> {
     /// # Examples
     ///
     /// ```
+    /// #![feature(inner_deref)]
+    /// let mut s = "HELLO".to_string();
     /// let mut x: Result<String, u32> = Ok("hello".to_string());
-    /// let y: Result<&mut str, &mut u32> = Ok("HELLO");
+    /// let y: Result<&mut str, &mut u32> = Ok(&mut s);
     /// assert_eq!(x.as_deref_mut().map(|x| { x.make_ascii_uppercase(); x }), y);
     ///
+    /// let mut i = 42;
     /// let mut x: Result<String, u32> = Err(42);
-    /// let y: Result<&mut str, &mut u32> = Err(&42);
+    /// let y: Result<&mut str, &mut u32> = Err(&mut i);
     /// assert_eq!(x.as_deref_mut().map(|x| { x.make_ascii_uppercase(); x }), y);
     /// ```
     pub fn as_deref_mut(&mut self) -> Result<&mut T::Target, &mut E> {

Diff for: src/libcore/time.rs

@@ -31,7 +31,7 @@ const MICROS_PER_SEC: u64 = 1_000_000;
 /// the number of nanoseconds.
 ///
 /// `Duration`s implement many common traits, including [`Add`], [`Sub`], and other
-/// [`ops`] traits.
+/// [`ops`] traits. It implements `Default` by returning a zero-length `Duration`.
 ///
 /// [`Add`]: ../../std/ops/trait.Add.html
 /// [`Sub`]: ../../std/ops/trait.Sub.html
@@ -138,6 +138,24 @@ impl Duration {
         Duration { secs, nanos }
     }
 
+    /// Creates a new `Duration` that spans no time.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(duration_zero)]
+    /// use std::time::Duration;
+    ///
+    /// let duration = Duration::zero();
+    /// assert!(duration.is_zero());
+    /// assert_eq!(duration.as_nanos(), 0);
+    /// ```
+    #[unstable(feature = "duration_zero", issue = "73544")]
+    #[inline]
+    pub const fn zero() -> Duration {
+        Duration { secs: 0, nanos: 0 }
+    }
+
     /// Creates a new `Duration` from the specified number of whole seconds.
     ///
     /// # Examples
@@ -223,6 +241,29 @@ impl Duration {
         }
     }
 
+    /// Returns true if this `Duration` spans no time.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(duration_zero)]
+    /// use std::time::Duration;
+    ///
+    /// assert!(Duration::zero().is_zero());
+    /// assert!(Duration::new(0, 0).is_zero());
+    /// assert!(Duration::from_nanos(0).is_zero());
+    /// assert!(Duration::from_secs(0).is_zero());
+    ///
+    /// assert!(!Duration::new(1, 1).is_zero());
+    /// assert!(!Duration::from_nanos(1).is_zero());
+    /// assert!(!Duration::from_secs(1).is_zero());
+    /// ```
+    #[unstable(feature = "duration_zero", issue = "73544")]
+    #[inline]
+    pub const fn is_zero(&self) -> bool {
+        self.secs == 0 && self.nanos == 0
+    }
+
     /// Returns the number of _whole_ seconds contained by this `Duration`.
     ///
     /// The returned value does not include the fractional (nanosecond) part of the