1 files changed, 81 insertions, 0 deletions
diff --git a/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp b/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp
new file mode 100644
index 0000000000000..c8a0287314bfd
--- /dev/null
+++ b/test/std/thread/thread.mutex/thread.lock/thread.lock.shared/thread.lock.shared.cons/mutex.pass.cpp
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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;
+
+// explicit shared_lock(mutex_type& m);
+
+#include <shared_mutex>
+#include <thread>
+#include <vector>
+#include <cstdlib>
+#include <cassert>
+
+#if _LIBCPP_STD_VER > 11
+
+std::shared_timed_mutex m;
+
+typedef std::chrono::system_clock Clock;
+typedef Clock::time_point time_point;
+typedef Clock::duration duration;
+typedef std::chrono::milliseconds ms;
+typedef std::chrono::nanoseconds ns;
+
+void f()
+{
+    time_point t0 = Clock::now();
+    time_point t1;
+    {
+    std::shared_lock<std::shared_timed_mutex> ul(m);
+    t1 = Clock::now();
+    }
+    ns d = t1 - t0 - ms(250);
+    assert(d < ms(50));  // within 50ms
+}
+
+void g()
+{
+    time_point t0 = Clock::now();
+    time_point t1;
+    {
+    std::shared_lock<std::shared_timed_mutex> ul(m);
+    t1 = Clock::now();
+    }
+    ns d = t1 - t0;
+    assert(d < ms(50));  // within 50ms
+}
+
+#endif  // _LIBCPP_STD_VER > 11
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    m.lock();
+    std::vector<std::thread> v;
+    for (int i = 0; i < 5; ++i)
+        v.push_back(std::thread(f));
+    std::this_thread::sleep_for(ms(250));
+    m.unlock();
+    for (auto& t : v)
+        t.join();
+    m.lock_shared();
+    for (auto& t : v)
+        t = std::thread(g);
+    std::thread q(f);
+    std::this_thread::sleep_for(ms(250));
+    m.unlock_shared();
+    for (auto& t : v)
+        t.join();
+    q.join();
+#endif  // _LIBCPP_STD_VER > 11
+}