diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 84c4b3a..8778a7d 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -20,7 +20,7 @@ jobs:
         uses: KyleMayes/install-llvm-action@v2
         if: matrix.platform == 'windows-latest'
         with:
-          version: 21.1.2
+          version: 20.1.8
           directory: ${{ runner.temp }}/llvm
       - name: Set LIBCLANG_PATH
         run: echo "LIBCLANG_PATH=$((gcm clang).source -replace "clang.exe")" >> $env:GITHUB_ENV
diff --git a/src/lib.rs b/src/lib.rs
index a725a1c..88281f2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -62,7 +62,7 @@ mod bindings {
         pub type c_ushort = u16;
         pub type c_uint = u32;
         pub type c_int = i32;
-        pub type c_ulong = u64;
+        pub type c_ulong = usize;
     }
     #[cfg(feature = "std")]
     mod types {