Add test for Amanieu#203

Author: Amanieu

tests/issue_203.rs

@@ -0,0 +1,26 @@
+use parking_lot::RwLock;
+use std::thread;
+
+struct Bar(RwLock<()>);
+
+impl Drop for Bar {
+    fn drop(&mut self) {
+        let _n = self.0.write();
+    }
+}
+
+thread_local! {
+    static B: Bar = Bar(RwLock::new(()));
+}
+
+#[test]
+fn main() {
+    thread::spawn(|| {
+        B.with(|_| ());
+
+        let a = RwLock::new(());
+        let _a = a.read();
+    })
+    .join()
+    .unwrap();
+}