1 files changed, 23 insertions, 0 deletions
diff --git a/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp
new file mode 100644
index 00000000000..c4714276432
--- /dev/null
+++ b/libcxx/test/std/thread/thread.mutex/thread.once/thread.once.onceflag/assign.fail.cpp
@@ -0,0 +1,23 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <mutex>
+
+// struct once_flag;
+
+// once_flag& operator=(const once_flag&) = delete;
+
+#include <mutex>
+
+int main()
+{
+    std::once_flag f;
+    std::once_flag f2;
+    f2 = f;
+}