vendor/libc++/r256633

16 files changed, 633 insertions, 0 deletions

diff --git a/test/std/utilities/time/date.time/ctime.pass.cpp b/test/std/utilities/time/date.time/ctime.pass.cpp
new file mode 100644
index 000000000000..d0a838e0c271
--- /dev/null
+++ b/test/std/utilities/time/date.time/ctime.pass.cpp
@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+#include <ctime>
+#include <type_traits>
+
+#ifndef NULL
+#error NULL not defined
+#endif
+
+#ifndef CLOCKS_PER_SEC
+#error CLOCKS_PER_SEC not defined
+#endif
+
+int main()
+{
+    std::clock_t c = 0;
+    ((void)c); // avoid unused warning
+    std::size_t s = 0;
+    std::time_t t = 0;
+    std::tm tm = {0};
+    char str[3];
+    static_assert((std::is_same<decltype(std::clock()), std::clock_t>::value), "");
+    static_assert((std::is_same<decltype(std::difftime(t,t)), double>::value), "");
+    static_assert((std::is_same<decltype(std::mktime(&tm)), std::time_t>::value), "");
+    static_assert((std::is_same<decltype(std::time(&t)), std::time_t>::value), "");
+#ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
+    static_assert((std::is_same<decltype(std::asctime(&tm)), char*>::value), "");
+    static_assert((std::is_same<decltype(std::ctime(&t)), char*>::value), "");
+    static_assert((std::is_same<decltype(std::gmtime(&t)), std::tm*>::value), "");
+    static_assert((std::is_same<decltype(std::localtime(&t)), std::tm*>::value), "");
+#endif
+    static_assert((std::is_same<decltype(std::strftime(str,s,"",&tm)), std::size_t>::value), "");
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp b/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp
new file mode 100644
index 000000000000..221004c568ce
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.alg/abs.fail.cpp
@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// ceil
+
+// template <class Rep, class Period>
+//   constexpr duration<Rep, Period> abs(duration<Rep, Period> d)
+
+// This function shall not participate in overload resolution unless numeric_limits<Rep>::is_signed is true.
+
+#include <chrono>
+
+typedef std::chrono::duration<unsigned> unsigned_secs;
+
+int main()
+{
+    std::chrono::abs(unsigned_secs(0));
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp b/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp
new file mode 100644
index 000000000000..ec32c37a9423
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.alg/abs.pass.cpp
@@ -0,0 +1,50 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+
+// <chrono>
+
+// abs
+
+// template <class Rep, class Period>
+//   constexpr duration<Rep, Period> abs(duration<Rep, Period> d)
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class Duration>
+void
+test(const Duration& f, const Duration& d)
+{
+    {
+    typedef decltype(std::chrono::abs(f)) R;
+    static_assert((std::is_same<R, Duration>::value), "");
+    assert(std::chrono::abs(f) == d);
+    }
+}
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::milliseconds( 7290000));
+    test(std::chrono::milliseconds(-7290000), std::chrono::milliseconds( 7290000));
+    test(std::chrono::minutes( 122), std::chrono::minutes( 122));
+    test(std::chrono::minutes(-122), std::chrono::minutes( 122));
+    test(std::chrono::hours(0), std::chrono::hours(0));
+
+    {
+//  9000000ms is 2 hours and 30 minutes
+    constexpr std::chrono::hours h1 = std::chrono::abs(std::chrono::hours(-3));
+    static_assert(h1.count() == 3, "");
+    constexpr std::chrono::hours h2 = std::chrono::abs(std::chrono::hours(3));
+    static_assert(h2.count() == 3, "");
+    }
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp b/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp
new file mode 100644
index 000000000000..909e8573247c
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.cast/ceil.fail.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// ceil
+
+// template <class ToDuration, class Rep, class Period>
+//   ToDuration
+//   ceil(const duration<Rep, Period>& d);
+
+// ToDuration shall be an instantiation of duration.
+
+#include <chrono>
+
+int main()
+{
+    std::chrono::ceil<int>(std::chrono::milliseconds(3));
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.cast/ceil.pass.cpp b/test/std/utilities/time/time.duration/time.duration.cast/ceil.pass.cpp
new file mode 100644
index 000000000000..6fb73b97db17
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.cast/ceil.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.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14
+
+// <chrono>
+
+// ceil
+
+// template <class ToDuration, class Rep, class Period>
+//   constexpr
+//   ToDuration
+//   ceil(const duration<Rep, Period>& d);
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class ToDuration, class FromDuration>
+void
+test(const FromDuration& f, const ToDuration& d)
+{
+    {
+    typedef decltype(std::chrono::ceil<ToDuration>(f)) R;
+    static_assert((std::is_same<R, ToDuration>::value), "");
+    assert(std::chrono::ceil<ToDuration>(f) == d);
+    }
+}
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::hours( 3));
+    test(std::chrono::milliseconds(-7290000), std::chrono::hours(-2));
+    test(std::chrono::milliseconds( 7290000), std::chrono::minutes( 122));
+    test(std::chrono::milliseconds(-7290000), std::chrono::minutes(-121));
+
+    {
+//  9000000ms is 2 hours and 30 minutes
+    constexpr std::chrono::hours h1 = std::chrono::ceil<std::chrono::hours>(std::chrono::milliseconds(9000000));
+    static_assert(h1.count() == 3, "");
+    constexpr std::chrono::hours h2 = std::chrono::ceil<std::chrono::hours>(std::chrono::milliseconds(-9000000));
+    static_assert(h2.count() == -2, "");
+    }
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp b/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp
new file mode 100644
index 000000000000..14d9ca878df8
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.cast/floor.fail.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// floor
+
+// template <class ToDuration, class Rep, class Period>
+//   ToDuration
+//   floor(const duration<Rep, Period>& d);
+
+// ToDuration shall be an instantiation of duration.
+
+#include <chrono>
+
+int main()
+{
+    std::chrono::floor<int>(std::chrono::milliseconds(3));
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp b/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp
new file mode 100644
index 000000000000..57929dd91228
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.cast/floor.pass.cpp
@@ -0,0 +1,50 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// floor
+
+// template <class ToDuration, class Rep, class Period>
+//   constexpr
+//   ToDuration
+//   floor(const duration<Rep, Period>& d);
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class ToDuration, class FromDuration>
+void
+test(const FromDuration& f, const ToDuration& d)
+{
+    {
+    typedef decltype(std::chrono::floor<ToDuration>(f)) R;
+    static_assert((std::is_same<R, ToDuration>::value), "");
+    assert(std::chrono::floor<ToDuration>(f) == d);
+    }
+}
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
+    test(std::chrono::milliseconds(-7290000), std::chrono::hours(-3));
+    test(std::chrono::milliseconds( 7290000), std::chrono::minutes( 121));
+    test(std::chrono::milliseconds(-7290000), std::chrono::minutes(-122));
+
+    {
+//  9000000ms is 2 hours and 30 minutes
+    constexpr std::chrono::hours h1 = std::chrono::floor<std::chrono::hours>(std::chrono::milliseconds(9000000));
+    static_assert(h1.count() == 2, "");
+    constexpr std::chrono::hours h2 = std::chrono::floor<std::chrono::hours>(std::chrono::milliseconds(-9000000));
+    static_assert(h2.count() == -3, "");
+    }
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp b/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp
new file mode 100644
index 000000000000..6f9f5bd29b63
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.cast/round.fail.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// round
+
+// template <class ToDuration, class Rep, class Period>
+//   ToDuration
+//   round(const duration<Rep, Period>& d);
+
+// ToDuration shall be an instantiation of duration.
+
+#include <chrono>
+
+int main()
+{
+    std::chrono::round<int>(std::chrono::milliseconds(3));
+}
diff --git a/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp b/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp
new file mode 100644
index 000000000000..e50b85c991a2
--- /dev/null
+++ b/test/std/utilities/time/time.duration/time.duration.cast/round.pass.cpp
@@ -0,0 +1,50 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// round
+
+// template <class ToDuration, class Rep, class Period>
+//   constexpr
+//   ToDuration
+//   ceil(const duration<Rep, Period>& d);
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class ToDuration, class FromDuration>
+void
+test(const FromDuration& f, const ToDuration& d)
+{
+    {
+    typedef decltype(std::chrono::round<ToDuration>(f)) R;
+    static_assert((std::is_same<R, ToDuration>::value), "");
+    assert(std::chrono::round<ToDuration>(f) == d);
+    }
+}
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
+    test(std::chrono::milliseconds(-7290000), std::chrono::hours(-2));
+    test(std::chrono::milliseconds( 7290000), std::chrono::minutes( 122));
+    test(std::chrono::milliseconds(-7290000), std::chrono::minutes(-122));
+
+    {
+//  9000000ms is 2 hours and 30 minutes
+    constexpr std::chrono::hours h1 = std::chrono::round<std::chrono::hours>(std::chrono::milliseconds(9000000));
+    static_assert(h1.count() == 2, "");
+    constexpr std::chrono::hours h2 = std::chrono::round<std::chrono::hours>(std::chrono::milliseconds(-9000000));
+    static_assert(h2.count() == -2, "");
+    }
+}
diff --git a/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp b/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp
new file mode 100644
index 000000000000..1c92d75b97ca
--- /dev/null
+++ b/test/std/utilities/time/time.point/time.point.cast/ceil.fail.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// ceil
+
+// template <class ToDuration, class Clock, class Duration>
+//   time_point<Clock, ToDuration>
+//   ceil(const time_point<Clock, Duration>& t);
+
+// ToDuration shall be an instantiation of duration.
+
+#include <chrono>
+
+int main()
+{
+    std::chrono::ceil<int>(std::chrono::system_clock::now());
+}
diff --git a/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp b/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp
new file mode 100644
index 000000000000..379929c7f2d8
--- /dev/null
+++ b/test/std/utilities/time/time.point/time.point.cast/ceil.pass.cpp
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// ceil
+
+// template <class ToDuration, class Clock, class Duration>
+//   time_point<Clock, ToDuration>
+//   ceil(const time_point<Clock, Duration>& t);
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class FromDuration, class ToDuration>
+void
+test(const FromDuration& df, const ToDuration& d)
+{
+    typedef std::chrono::system_clock Clock;
+    typedef std::chrono::time_point<Clock, FromDuration> FromTimePoint;
+    typedef std::chrono::time_point<Clock, ToDuration> ToTimePoint;
+    {
+    FromTimePoint f(df);
+    ToTimePoint t(d);
+    typedef decltype(std::chrono::ceil<ToDuration>(f)) R;
+    static_assert((std::is_same<R, ToTimePoint>::value), "");
+    assert(std::chrono::ceil<ToDuration>(f) == t);
+    }
+}
+
+template<class FromDuration, long long From, class ToDuration, long long To>
+void test_constexpr ()
+{
+    typedef std::chrono::system_clock Clock;
+    typedef std::chrono::time_point<Clock, FromDuration> FromTimePoint;
+    typedef std::chrono::time_point<Clock, ToDuration> ToTimePoint;
+    {
+    constexpr FromTimePoint f{FromDuration{From}};
+    constexpr ToTimePoint   t{ToDuration{To}};
+    static_assert(std::chrono::ceil<ToDuration>(f) == t, "");
+    }
+}
+
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::hours( 3));
+    test(std::chrono::milliseconds(-7290000), std::chrono::hours(-2));
+    test(std::chrono::milliseconds( 7290000), std::chrono::minutes( 122));
+    test(std::chrono::milliseconds(-7290000), std::chrono::minutes(-121));
+
+//  9000000ms is 2 hours and 30 minutes
+    test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::hours,    3> ();
+    test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::hours,   -2> ();
+    test_constexpr<std::chrono::milliseconds, 9000001, std::chrono::minutes, 151> ();
+    test_constexpr<std::chrono::milliseconds,-9000001, std::chrono::minutes,-150> ();
+
+    test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::seconds, 9000> ();
+    test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::seconds,-9000> ();
+}
diff --git a/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp b/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp
new file mode 100644
index 000000000000..ea48e1219e34
--- /dev/null
+++ b/test/std/utilities/time/time.point/time.point.cast/floor.fail.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// floor
+
+// template <class ToDuration, class Clock, class Duration>
+//   time_point<Clock, ToDuration>
+//   floor(const time_point<Clock, Duration>& t);
+
+// ToDuration shall be an instantiation of duration.
+
+#include <chrono>
+
+int main()
+{
+    std::chrono::floor<int>(std::chrono::system_clock::now());
+}
diff --git a/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp b/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp
new file mode 100644
index 000000000000..d0a908fa932a
--- /dev/null
+++ b/test/std/utilities/time/time.point/time.point.cast/floor.pass.cpp
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// floor
+
+// template <class ToDuration, class Clock, class Duration>
+//   time_point<Clock, ToDuration>
+//   floor(const time_point<Clock, Duration>& t);
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class FromDuration, class ToDuration>
+void
+test(const FromDuration& df, const ToDuration& d)
+{
+    typedef std::chrono::system_clock Clock;
+    typedef std::chrono::time_point<Clock, FromDuration> FromTimePoint;
+    typedef std::chrono::time_point<Clock, ToDuration> ToTimePoint;
+    {
+    FromTimePoint f(df);
+    ToTimePoint t(d);
+    typedef decltype(std::chrono::floor<ToDuration>(f)) R;
+    static_assert((std::is_same<R, ToTimePoint>::value), "");
+    assert(std::chrono::floor<ToDuration>(f) == t);
+    }
+}
+
+template<class FromDuration, long long From, class ToDuration, long long To>
+void test_constexpr ()
+{
+    typedef std::chrono::system_clock Clock;
+    typedef std::chrono::time_point<Clock, FromDuration> FromTimePoint;
+    typedef std::chrono::time_point<Clock, ToDuration> ToTimePoint;
+    {
+    constexpr FromTimePoint f{FromDuration{From}};
+    constexpr ToTimePoint   t{ToDuration{To}};
+    static_assert(std::chrono::floor<ToDuration>(f) == t, "");
+    }
+}
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
+    test(std::chrono::milliseconds(-7290000), std::chrono::hours(-3));
+    test(std::chrono::milliseconds( 7290000), std::chrono::minutes( 121));
+    test(std::chrono::milliseconds(-7290000), std::chrono::minutes(-122));
+
+//  9000000ms is 2 hours and 30 minutes
+    test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::hours,    2> ();
+    test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::hours,   -3> ();
+    test_constexpr<std::chrono::milliseconds, 9000001, std::chrono::minutes, 150> ();
+    test_constexpr<std::chrono::milliseconds,-9000001, std::chrono::minutes,-151> ();
+
+    test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::seconds, 9000> ();
+    test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::seconds,-9000> ();
+}
diff --git a/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp b/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp
new file mode 100644
index 000000000000..53c14f47de69
--- /dev/null
+++ b/test/std/utilities/time/time.point/time.point.cast/round.fail.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// round
+
+// template <class ToDuration, class Clock, class Duration>
+//   time_point<Clock, ToDuration>
+//   round(const time_point<Clock, Duration>& t);
+
+// ToDuration shall be an instantiation of duration.
+
+#include <chrono>
+
+int main()
+{
+    std::chrono::round<int>(std::chrono::system_clock::now());
+}
diff --git a/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp b/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp
new file mode 100644
index 000000000000..ab8bf3a75e79
--- /dev/null
+++ b/test/std/utilities/time/time.point/time.point.cast/round.pass.cpp
@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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: c++03, c++11, c++14
+// <chrono>
+
+// round
+
+// template <class ToDuration, class Clock, class Duration>
+//   time_point<Clock, ToDuration>
+//   round(const time_point<Clock, Duration>& t);
+
+#include <chrono>
+#include <type_traits>
+#include <cassert>
+
+template <class FromDuration, class ToDuration>
+void
+test(const FromDuration& df, const ToDuration& d)
+{
+    typedef std::chrono::system_clock Clock;
+    typedef std::chrono::time_point<Clock, FromDuration> FromTimePoint;
+    typedef std::chrono::time_point<Clock, ToDuration> ToTimePoint;
+    {
+    FromTimePoint f(df);
+    ToTimePoint t(d);
+    typedef decltype(std::chrono::round<ToDuration>(f)) R;
+    static_assert((std::is_same<R, ToTimePoint>::value), "");
+    assert(std::chrono::round<ToDuration>(f) == t);
+    }
+}
+
+template<class FromDuration, long long From, class ToDuration, long long To>
+void test_constexpr ()
+{
+    typedef std::chrono::system_clock Clock;
+    typedef std::chrono::time_point<Clock, FromDuration> FromTimePoint;
+    typedef std::chrono::time_point<Clock, ToDuration> ToTimePoint;
+    {
+    constexpr FromTimePoint f{FromDuration{From}};
+    constexpr ToTimePoint   t{ToDuration{To}};
+    static_assert(std::chrono::round<ToDuration>(f) == t, "");
+    }
+}
+
+int main()
+{
+//  7290000ms is 2 hours, 1 minute, and 30 seconds
+    test(std::chrono::milliseconds( 7290000), std::chrono::hours( 2));
+    test(std::chrono::milliseconds(-7290000), std::chrono::hours(-2));
+    test(std::chrono::milliseconds( 7290000), std::chrono::minutes( 122));
+    test(std::chrono::milliseconds(-7290000), std::chrono::minutes(-122));
+
+//  9000000ms is 2 hours and 30 minutes
+    test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::hours,    2> ();
+    test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::hours,   -2> ();
+    test_constexpr<std::chrono::milliseconds, 9000001, std::chrono::minutes, 150> ();
+    test_constexpr<std::chrono::milliseconds,-9000001, std::chrono::minutes,-150> ();
+
+    test_constexpr<std::chrono::milliseconds, 9000000, std::chrono::seconds, 9000> ();
+    test_constexpr<std::chrono::milliseconds,-9000000, std::chrono::seconds,-9000> ();
+}
diff --git a/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp b/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp
index c32350faa83b..f9ddc87a7a14 100644
--- a/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp
+++ b/test/std/utilities/time/time.traits/time.traits.is_fp/treat_as_floating_point.pass.cpp
@@ -20,6 +20,10 @@ test()
 {
     static_assert((std::is_base_of<std::is_floating_point<T>,
                                    std::chrono::treat_as_floating_point<T> >::value), "");
+#if TEST_STD_VER > 14
+    static_assert((std::is_base_of<std::is_floating_point<T>,
+                                   std::chrono::treat_as_floating_point_v<T> >), "");
+#endif
 }
 
 struct A {};