--- /dev/null
+++ xnu/xnu-11215.81.4/tests/intrusive_shared_ptr_src/compare.equal.nullptr.cpp
@@ -0,0 +1,62 @@
+//
+// Tests for
+//  template <typename T, typename R>
+//  bool operator==(intrusive_shared_ptr<T, R> const& x, std::nullptr_t);
+//
+//  template <typename T, typename R>
+//  bool operator!=(intrusive_shared_ptr<T, R> const& x, std::nullptr_t);
+//
+//  template <typename T, typename R>
+//  bool operator==(std::nullptr_t, intrusive_shared_ptr<T, R> const& x);
+//
+//  template <typename T, typename R>
+//  bool operator!=(std::nullptr_t, intrusive_shared_ptr<T, R> const& x);
+//
+
+#include <libkern/c++/intrusive_shared_ptr.h>
+#include <darwintest.h>
+#include "test_policy.h"
+
+struct T { int i; };
+
+template <typename T, typename U>
+static void
+check_eq(T t, U u)
+{
+	CHECK(t == u);
+	CHECK(u == t);
+	CHECK(!(t != u));
+	CHECK(!(u != t));
+}
+
+template <typename T, typename U>
+static void
+check_ne(T t, U u)
+{
+	CHECK(!(t == u));
+	CHECK(!(u == t));
+	CHECK(t != u);
+	CHECK(u != t);
+}
+
+template <typename T, typename TQual>
+static void
+tests()
+{
+	T obj{3};
+
+	{
+		test_shared_ptr<TQual> const a(&obj, libkern::no_retain);
+		check_ne(a, nullptr);
+	}
+
+	{
+		test_shared_ptr<TQual> const a = nullptr;
+		check_eq(a, nullptr);
+	}
+}
+
+T_DECL(compare_equal_nullptr, "intrusive_shared_ptr.compare.equal.nullptr", T_META_TAG_VM_PREFERRED) {
+	tests<T, T>();
+	tests<T, T const>();
+}