Fix Windows backend import condition to match cfg_if! logic

.github/workflows/test.yml

@@ -386,3 +386,25 @@ jobs:
           echo "${{ runner.tool_cache }}/wasmtime-v24.0.0-x86_64-linux" >> $GITHUB_PATH
           echo "CARGO_TARGET_WASM32_WASIP1_RUNNER=wasmtime run --" >> $GITHUB_ENV
       - run: cargo test --target wasm32-wasip1 --all -- --nocapture
+
+  miri-test:
+    name: Test stacker with Miri on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install Rust nightly with Miri
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: nightly
+          profile: minimal
+          components: miri
+          default: true
+      - name: Setup Miri
+        run: cargo miri setup
+      - name: Test with Miri
+        run: cargo miri test -- --nocapture

src/lib.rs

@@ -169,12 +169,12 @@ psm_stack_manipulation! {
     }
 
     no {
-        #[cfg(not(windows))]
+        #[cfg(not(all(windows, not(miri))))]
         fn _grow(stack_size: usize, callback: &mut dyn FnMut()) {
             let _ = stack_size;
             callback();
         }
-        #[cfg(windows)]
+        #[cfg(all(windows, not(miri)))]
         use backends::windows::_grow;
     }
 }

tests/simple.rs

@@ -18,6 +18,7 @@ fn recurse(n: usize) {
 }
 
 #[test]
+#[cfg_attr(miri, ignore)] // Too slow under Miri's interpreter
 fn foo() {
     let limit = if cfg!(target_arch = "wasm32") {
         2000

tests/smoke.rs

@@ -21,7 +21,7 @@ fn deep() {
         }
     }
 
-    let limit = if cfg!(target_arch = "wasm32") {
+    let limit = if cfg!(target_arch = "wasm32") || cfg!(miri) {
         2000
     } else {
         256 * 1024
@@ -31,6 +31,7 @@ fn deep() {
 
 #[test]
 #[cfg_attr(target_arch = "wasm32", ignore)]
+#[cfg_attr(miri, ignore)] // Too slow under Miri's interpreter
 fn panic() {
     fn foo(n: usize, s: &mut [u8]) {
         __stacker_black_box(s.as_ptr());