1 files changed, 62 insertions, 0 deletions
diff --git a/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp b/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp
new file mode 100644
index 000000000000..eb08a45cde6e
--- /dev/null
+++ b/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.locking/unlock.pass.cpp
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// UNSUPPORTED: libcpp-has-no-threads
+
+// <shared_mutex>
+
+// template <class Mutex> class shared_lock;
+
+// void unlock();
+
+#include <shared_mutex>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+bool unlock_called = false;
+
+struct mutex
+{
+    void lock_shared() {}
+    void unlock_shared() {unlock_called = true;}
+};
+
+mutex m;
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    std::shared_lock<mutex> lk(m);
+    lk.unlock();
+    assert(unlock_called == true);
+    assert(lk.owns_lock() == false);
+    try
+    {
+        lk.unlock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+    lk.release();
+    try
+    {
+        lk.unlock();
+        assert(false);
+    }
+    catch (std::system_error& e)
+    {
+        assert(e.code().value() == EPERM);
+    }
+#endif  // _LIBCPP_STD_VER > 11
+}