aarch64 windows: Use windows-bindgen to avoid windows-sys dependency.

Cargo.toml

@@ -172,8 +172,8 @@ libc = { version = "0.2.172", default-features = false }
 [target.'cfg(all(all(target_arch = "aarch64", target_endian = "little"), target_vendor = "apple", any(target_os = "ios", target_os = "macos", target_os = "tvos", target_os = "visionos", target_os = "watchos")))'.dependencies]
 libc = { version = "0.2.172", default-features = false }
 
-[target.'cfg(all(all(target_arch = "aarch64", target_endian = "little"), target_os = "windows"))'.dependencies]
-windows-sys = { version = "0.61.2", features = ["Win32_Foundation", "Win32_System_Threading"] }
+[target.'cfg(all(target_arch = "aarch64", target_os = "windows"))'.dependencies]
+windows-link = { version = "0.2.1" }
 
 [target.'cfg(all(target_arch = "wasm32", target_os = "unknown"))'.dev-dependencies]
 wasm-bindgen-test = { version = "0.3.64", default-features = false, features = ["std"] }
@@ -236,10 +236,13 @@ overflow-checks = true
 
 [workspace]
 members = [
-    # intentionally not a default member so that `cargo test` doesn't cause criterion.rs and all its
+    # Not a default member so that `cargo test` doesn't cause criterion.rs and all its
     # dependencies to get built.
     "bench",
 
+    # Not a defailt member as we regenerate bindings manually.
+    "build/bindgen",
+
     "cavp",
 ]
 default-members = [

build/bindgen/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "ring-bindgen"
+edition = "2024"
+publish = false
+version = "0.1.0"
+
+[[bin]]
+name = "bindgen"
+
+[dependencies]
+windows-bindgen = "0.66"

build/bindgen/src/bin/bindgen.rs

@@ -0,0 +1,14 @@
+// Run `cargo run -p ring-bindgen` in the Cargo workspace root directory.
+
+fn main() {
+    windows_bindgen::bindgen([
+        "--out",
+        "src/polyfill/aarch64_windows.rs",
+        "--sys",
+        "--no-deps",
+        "--filter",
+        "IsProcessorFeaturePresent",
+        "PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE",
+    ])
+    .unwrap()
+}

src/cpu/aarch64/windows.rs

@@ -13,7 +13,7 @@
 // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 use super::{Aes, CAPS_STATIC, Neon, PMull, Sha256};
-use windows_sys::Win32::System::Threading::{
+use crate::polyfill::aarch64_windows::Windows::Win32::System::Threading::{
     IsProcessorFeaturePresent, PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE,
 };
 

src/polyfill/aarch64_windows.rs

@@ -0,0 +1,22 @@
+// Bindings generated by `windows-bindgen` 0.66.0
+
+#![allow(
+    non_snake_case,
+    non_upper_case_globals,
+    non_camel_case_types,
+    dead_code,
+    clippy::all
+)]
+
+pub type BOOL = i32;
+pub mod Windows {
+    pub mod Win32 {
+        pub mod System {
+            pub mod Threading {
+                windows_link::link!("kernel32.dll" "system" fn IsProcessorFeaturePresent(processorfeature : PROCESSOR_FEATURE_ID) -> super::super::super::super::BOOL);
+                pub const PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE: PROCESSOR_FEATURE_ID = 30u32;
+                pub type PROCESSOR_FEATURE_ID = u32;
+            }
+        }
+    }
+}

src/polyfill/mod.rs

@@ -91,6 +91,9 @@ mod test;
 pub(crate) mod uninit;
 mod uninit_slice;
 
+#[cfg(all(target_arch = "aarch64", target_os = "windows"))]
+pub(crate) mod aarch64_windows;
+
 pub use self::{array_flat_map::ArrayFlatMap, array_split_map::ArraySplitMap, notsend::NotSend};
 
 #[allow(unused_imports)]