1 files changed, 51 insertions, 0 deletions
diff --git a/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp b/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp
new file mode 100644
index 00000000000..fb9ce642299
--- /dev/null
+++ b/libcxx/test/std/utilities/template.bitset/bitset.members/count.pass.cpp
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// test size_t count() const;
+
+#include <bitset>
+#include <cstdlib>
+#include <cassert>
+
+#pragma clang diagnostic ignored "-Wtautological-compare"
+
+template <std::size_t N>
+std::bitset<N>
+make_bitset()
+{
+    std::bitset<N> v;
+    for (std::size_t i = 0; i < N; ++i)
+        v[i] = static_cast<bool>(std::rand() & 1);
+    return v;
+}
+
+template <std::size_t N>
+void test_count()
+{
+    const std::bitset<N> v = make_bitset<N>();
+    std::size_t c1 = v.count();
+    std::size_t c2 = 0;
+    for (std::size_t i = 0; i < N; ++i)
+        if (v[i])
+            ++c2;
+    assert(c1 == c2);
+}
+
+int main()
+{
+    test_count<0>();
+    test_count<1>();
+    test_count<31>();
+    test_count<32>();
+    test_count<33>();
+    test_count<63>();
+    test_count<64>();
+    test_count<65>();
+    test_count<1000>();
+}