ci: add windows arm64 pre-builds

.github/workflows/ci.yml

@@ -111,6 +111,12 @@ jobs:
             v8_enable_pointer_compression: false
             cargo: cargo
 
+          - os: ${{ github.repository == 'denoland/rusty_v8' && 'windows-11-arm-xl' || 'windows-11-arm' }}
+            target: aarch64-pc-windows-msvc
+            variant: release # Note: we do not support windows debug builds.
+            v8_enable_pointer_compression: false
+            cargo: cargo
+
           - os: ${{ github.repository == 'denoland/rusty_v8' && 'ubuntu-22.04-xl' || 'ubuntu-22.04' }}
             target: aarch64-unknown-linux-gnu
             variant: debug
@@ -208,6 +214,7 @@ jobs:
                "x86_64-unknown-linux-gnu"  = "x86_64-unknown-linux-musl"
                "aarch64-unknown-linux-gnu" = "aarch64-unknown-linux-musl"
                "x86_64-pc-windows-msvc"    = "x86_64-pc-windows-msvc"
+               "aarch64-pc-windows-msvc"    = "aarch64-pc-windows-msvc"
              }['${{ matrix.config.target }}']
           $basename = "sccache-$version-$platform"
           $url = "https://github.com/mozilla/sccache/releases/download/$version/$basename.tar.gz"

build.rs

@@ -189,6 +189,7 @@ fn build_binding() {
   ];
 
   let target_os = env::var("CARGO_CFG_TARGET_OS").unwrap();
+  let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap();
   if target_os == "macos" {
     let output = Command::new("xcrun")
       .args(["--show-sdk-path"])
@@ -214,6 +215,9 @@ fn build_binding() {
     }
   }
 
+  if target_os == "windows" && target_arch == "aarch64" {
+    clang_args.push("--target=aarch64-pc-windows-msvc".to_string());
+  }
   let bindings = bindgen::Builder::default()
     .header("src/binding.hpp")
     .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
@@ -310,10 +314,11 @@ fn build_v8(is_asan: bool) {
   ));
 
   // Fix GN's host_cpu detection when using x86_64 bins on Apple Silicon
-  if cfg!(target_os = "macos") && cfg!(target_arch = "aarch64") {
+  if cfg!(target_arch = "aarch64")
+    && (cfg!(target_os = "macos") || cfg!(target_os = "windows"))
+  {
     gn_args.push("host_cpu=\"arm64\"".to_string());
   }
-
   if env::var_os("DISABLE_CLANG").is_some() {
     gn_args.push("is_clang=false".into());
     // -gline-tables-only is Clang-only
@@ -352,9 +357,11 @@ fn build_v8(is_asan: bool) {
   // cross-compilation setup
   if target_arch == "aarch64" {
     gn_args.push(r#"target_cpu="arm64""#.to_string());
-    gn_args.push("use_sysroot=true".to_string());
-    maybe_install_sysroot("arm64");
-    maybe_install_sysroot("amd64");
+    if target_os == "linux" {
+      gn_args.push("use_sysroot=true".to_string());
+      maybe_install_sysroot("arm64");
+      maybe_install_sysroot("amd64");
+    }
   }
   if target_arch == "arm" {
     gn_args.push(r#"target_cpu="arm""#.to_string());

rust-toolchain.toml

@@ -7,6 +7,7 @@ targets = [
     "x86_64-unknown-linux-gnu",
     "aarch64-unknown-linux-gnu",
     "x86_64-pc-windows-msvc",
+    "aarch64-pc-windows-msvc",
     "aarch64-linux-android",
     "x86_64-linux-android",
 ]

tools/rust_toolchain.py

@@ -29,12 +29,16 @@
     'host_cpu': host_cpu,
 }
 
-dep = deps[DIR]
-obj = next(obj for obj in dep['objects'] if eval(obj['condition'], eval_globals))
-bucket = dep['bucket']
-name = obj['object_name']
-url = f'https://storage.googleapis.com/{bucket}/{name}'
-
+if host_os == 'windows' and host_cpu == 'arm64':
+    nightly_toolchain = 'nightly-2025-12-04'
+    target_triple = 'aarch64-pc-windows-msvc'
+    url = f'https://static.rust-lang.org/dist/{nightly_toolchain}/rust-{nightly_toolchain}-{target_triple}.tar.xz'
+else:
+    dep = deps[DIR]
+    obj = next(obj for obj in dep['objects'] if eval(obj['condition'], eval_globals))
+    bucket = dep['bucket']
+    name = obj['object_name']
+    url = f'https://storage.googleapis.com/{bucket}/{name}'
 
 def EnsureDirExists(path):
     if not os.path.exists(path):