diff --git a/libcxx/src/chrono.cpp b/libcxx/src/chrono.cpp
--- a/libcxx/src/chrono.cpp
+++ b/libcxx/src/chrono.cpp
@@ -114,14 +114,14 @@
 
 #if defined(__APPLE__)
 
-// Darwin libc versions >= 1133 provide ns precision via CLOCK_UPTIME_RAW
-#if defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_UPTIME_RAW)
+// Darwin libc versions >= 1133 provide ns precision via CLOCK_MONOTONIC_RAW
+#if defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC_RAW)
 steady_clock::time_point
 steady_clock::now() _NOEXCEPT
 {
     struct timespec tp;
-    if (0 != clock_gettime(CLOCK_UPTIME_RAW, &tp))
-        __throw_system_error(errno, "clock_gettime(CLOCK_UPTIME_RAW) failed");
+    if (0 != clock_gettime(CLOCK_MONOTONIC_RAW, &tp))
+        __throw_system_error(errno, "clock_gettime(CLOCK_MONOTONIC_RAW) failed");
     return time_point(seconds(tp.tv_sec) + nanoseconds(tp.tv_nsec));
 }
 
@@ -177,7 +177,7 @@
     static FP fp = init_steady_clock();
     return time_point(duration(fp()));
 }
-#endif // defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_UPTIME_RAW)
+#endif // defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC_RAW)
 
 #elif defined(_LIBCPP_WIN32API)
 
@@ -206,9 +206,9 @@
 
 #elif defined(CLOCK_MONOTONIC)
 
-// On Apple platforms only CLOCK_UPTIME_RAW or mach_absolute_time are able to
-// time functions in the nanosecond range. Thus, they are the only acceptable
-// implementations of steady_clock.
+// On Apple platforms only CLOCK_UPTIME_RAW, CLOCK_MONOTONIC_RAW or
+// mach_absolute_time are able to time functions in the nanosecond range.
+// Thus, they are the only acceptable implementations of steady_clock.
 #ifdef __APPLE__
 #error "Never use CLOCK_MONOTONIC for steady_clock::now on Apple platforms"
 #endif