Support building rustup for Windows arm64

.github/workflows/windows-builds-on-master.yaml

@@ -21,6 +21,7 @@ jobs:
       matrix:
         target:
           - x86_64-pc-windows-msvc
+          - aarch64-pc-windows-msvc # skip-pr skip-stable
           - x86_64-pc-windows-gnu # skip-pr
         include:
           - target: x86_64-pc-windows-gnu
@@ -29,6 +30,8 @@ jobs:
           - target: i686-pc-windows-gnu
             mingwdir: mingw32
             mingw: https://ci-mirrors.rust-lang.org/rustc/i686-6.3.0-release-posix-dwarf-rt_v5-rev2.7z
+          - target: aarch64-pc-windows-msvc # skip-pr skip-stable
+            skip_tests: yes # skip-pr skip-stable
     steps:
       - uses: actions/checkout@v2
         # v2 defaults to a shallow checkout, but we need at least to the previous tag
@@ -62,7 +65,7 @@ jobs:
         run: |
           echo "%USERPROFILE%\.cargo\bin" | Out-File -Append -FilePath $env:GITHUB_PATH -Encoding utf8
           echo "TARGET=${{ matrix.target }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
-          echo "SKIP_TESTS=" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
+          echo "SKIP_TESTS=${{ matrix.skip_tests }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
       - name: Cache cargo registry and git trees
         uses: actions/cache@v2
         with:

.github/workflows/windows-builds-on-pr.yaml

@@ -59,7 +59,7 @@ jobs:
         run: |
           echo "%USERPROFILE%\.cargo\bin" | Out-File -Append -FilePath $env:GITHUB_PATH -Encoding utf8
           echo "TARGET=${{ matrix.target }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
-          echo "SKIP_TESTS=" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
+          echo "SKIP_TESTS=${{ matrix.skip_tests }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
       - name: Cache cargo registry and git trees
         uses: actions/cache@v2
         with:

.github/workflows/windows-builds-on-stable.yaml

@@ -62,7 +62,7 @@ jobs:
         run: |
           echo "%USERPROFILE%\.cargo\bin" | Out-File -Append -FilePath $env:GITHUB_PATH -Encoding utf8
           echo "TARGET=${{ matrix.target }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
-          echo "SKIP_TESTS=" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
+          echo "SKIP_TESTS=${{ matrix.skip_tests }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
       - name: Cache cargo registry and git trees
         uses: actions/cache@v2
         with:

ci/actions-templates/README.md

@@ -67,6 +67,7 @@ system.
 | x86_64-pc-windows-gnu         | No         | One   | No     | Yes        |
 | i686-pc-windows-msvc          | No         | One   | No     | No         |
 | i686-pc-windows-gnu           | No         | One   | No     | No         |
+| aarch64-pc-windows-msvc       | Yes        | Two   | No     | Yes        |
 
 We also have a clippy/shellcheck target which runs on x86_64 linux and is
 run in all cases. It does a `cargo fmt` check, a `cargo clippy` check on the

ci/actions-templates/windows-builds-template.yaml

@@ -28,6 +28,7 @@ jobs:
         target:
           - x86_64-pc-windows-msvc
           - i686-pc-windows-msvc # skip-pr skip-master
+          - aarch64-pc-windows-msvc # skip-pr skip-stable
           - x86_64-pc-windows-gnu # skip-pr
           - i686-pc-windows-gnu # skip-pr skip-master
         include:
@@ -37,6 +38,8 @@ jobs:
           - target: i686-pc-windows-gnu
             mingwdir: mingw32
             mingw: https://ci-mirrors.rust-lang.org/rustc/i686-6.3.0-release-posix-dwarf-rt_v5-rev2.7z
+          - target: aarch64-pc-windows-msvc # skip-pr skip-stable
+            skip_tests: yes # skip-pr skip-stable
     steps:
       - uses: actions/checkout@v2
         # v2 defaults to a shallow checkout, but we need at least to the previous tag
@@ -70,7 +73,7 @@ jobs:
         run: |
           echo "%USERPROFILE%\.cargo\bin" | Out-File -Append -FilePath $env:GITHUB_PATH -Encoding utf8
           echo "TARGET=${{ matrix.target }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
-          echo "SKIP_TESTS=" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
+          echo "SKIP_TESTS=${{ matrix.skip_tests }}" | Out-File -Append -FilePath $env:GITHUB_ENV -Encoding utf8
       - name: Cache cargo registry and git trees
         uses: actions/cache@v2
         with:

ci/run.bash

@@ -20,6 +20,7 @@ case "$TARGET" in
   mips* ) ;;
   riscv* ) ;;
   s390x* ) ;;
+  aarch64-pc-windows-msvc ) ;;
   # default case, build with rustls enabled
   * ) FEATURES+=('--features' 'reqwest-rustls-tls') ;;
 esac

doc/src/installation/windows.md

@@ -16,7 +16,7 @@ tools" and "Windows 10 SDK" option. No additional software installation is
 necessary for basic use of the GNU build.
 
 By default `rustup` on Windows configures Rust to target the MSVC ABI, that is
-a target triple of either `i686-pc-windows-msvc` or `x86_64-pc-windows-msvc`
+a target triple of either `i686-pc-windows-msvc`, `x86_64-pc-windows-msvc`, or `aarch64-pc-windows-msvc`
 depending on the CPU architecture of the host Windows OS. The toolchains that
 `rustup` chooses to install, unless told otherwise through the [toolchain
 specification], will be compiled to run on that target triple host and will

src/dist/dist.rs

@@ -234,6 +234,7 @@ impl TargetTriple {
             // First detect architecture
             const PROCESSOR_ARCHITECTURE_AMD64: u16 = 9;
             const PROCESSOR_ARCHITECTURE_INTEL: u16 = 0;
+            const PROCESSOR_ARCHITECTURE_ARM64: u16 = 12;
 
             let mut sys_info;
             unsafe {
@@ -244,6 +245,7 @@ impl TargetTriple {
             let arch = match unsafe { sys_info.u.s() }.wProcessorArchitecture {
                 PROCESSOR_ARCHITECTURE_AMD64 => "x86_64",
                 PROCESSOR_ARCHITECTURE_INTEL => "i686",
+                PROCESSOR_ARCHITECTURE_ARM64 => "aarch64",
                 _ => return None,
             };