1 files changed, 29 insertions, 0 deletions
diff --git a/lib/tsan/lit_tests/atomic_stack.cc b/lib/tsan/lit_tests/atomic_stack.cc
new file mode 100644
index 0000000000000..50f6a8a889ca8
--- /dev/null
+++ b/lib/tsan/lit_tests/atomic_stack.cc
@@ -0,0 +1,29 @@
+// RUN: %clangxx_tsan -O1 %s -o %t && %t 2>&1 | FileCheck %s
+#include <pthread.h>
+#include <unistd.h>
+
+int Global;
+
+void *Thread1(void *x) {
+  sleep(1);
+  __atomic_fetch_add(&Global, 1, __ATOMIC_RELAXED);
+  return NULL;
+}
+
+void *Thread2(void *x) {
+  Global++;
+  return NULL;
+}
+
+int main() {
+  pthread_t t[2];
+  pthread_create(&t[0], NULL, Thread1, NULL);
+  pthread_create(&t[1], NULL, Thread2, NULL);
+  pthread_join(t[0], NULL);
+  pthread_join(t[1], NULL);
+}
+
+// CHECK: WARNING: ThreadSanitizer: data race
+// CHECK:   Atomic write of size 4
+// CHECK:     #0 __tsan_atomic32_fetch_add
+// CHECK:     #1 Thread1