Vendor things

third-party/vendor/loom/tests/smoke.rs

@@ -0,0 +1,45 @@
+#![deny(warnings, rust_2018_idioms)]
+
+use loom::sync::atomic::AtomicUsize;
+use loom::thread;
+
+use std::sync::atomic::Ordering::{Acquire, Relaxed, Release};
+use std::sync::Arc;
+
+#[test]
+#[should_panic]
+fn checks_fail() {
+    struct BuggyInc {
+        num: AtomicUsize,
+    }
+
+    impl BuggyInc {
+        fn new() -> BuggyInc {
+            BuggyInc {
+                num: AtomicUsize::new(0),
+            }
+        }
+
+        fn inc(&self) {
+            let curr = self.num.load(Acquire);
+            self.num.store(curr + 1, Release);
+        }
+    }
+
+    loom::model(|| {
+        let buggy_inc = Arc::new(BuggyInc::new());
+
+        let ths: Vec<_> = (0..2)
+            .map(|_| {
+                let buggy_inc = buggy_inc.clone();
+                thread::spawn(move || buggy_inc.inc())
+            })
+            .collect();
+
+        for th in ths {
+            th.join().unwrap();
+        }
+
+        assert_eq!(2, buggy_inc.num.load(Relaxed));
+    });
+}