1 files changed, 39 insertions, 0 deletions
diff --git a/test/tsan/custom_mutex1.cc b/test/tsan/custom_mutex1.cc
new file mode 100644
index 000000000000..06186515f697
--- /dev/null
+++ b/test/tsan/custom_mutex1.cc
@@ -0,0 +1,39 @@
+// RUN: %clangxx_tsan -O1 --std=c++11 %s -o %t && %deflake %run %t 2>&1 | FileCheck %s
+#include "custom_mutex.h"
+
+// Test that failed TryLock does not induce parasitic synchronization.
+
+Mutex mu;
+long data;
+
+void *thr(void *arg) {
+  mu.Lock();
+  data++;
+  mu.Unlock();
+  mu.Lock();
+  barrier_wait(&barrier);
+  barrier_wait(&barrier);
+  mu.Unlock();
+  return 0;
+}
+
+int main() {
+  barrier_init(&barrier, 2);
+  pthread_t th;
+  pthread_create(&th, 0, thr, 0);
+  barrier_wait(&barrier);
+  if (mu.TryLock()) {
+    fprintf(stderr, "TryLock succeeded, should not\n");
+    exit(0);
+  }
+  data++;
+  barrier_wait(&barrier);
+  pthread_join(th, 0);
+  fprintf(stderr, "DONE\n");
+  return 0;
+}
+
+// CHECK: ThreadSanitizer: data race
+// CHECK-NEXT:   Write of size 8 at {{.*}} by main thread:
+// CHECK-NEXT:     #0 main {{.*}}custom_mutex1.cc:29
+// CHECK: DONE