Merge pull request #54 from michaelcontento/patch-1

Use ONCE.call_once instead of the old ONCE.doit

Author: alexcrichton

src/lib.rs

@@ -226,7 +226,7 @@ pub fn precise_time_ns() -> u64 {
                                                                                    denom: 0 };
         static ONCE: std::sync::Once = std::sync::ONCE_INIT;
         unsafe {
-            ONCE.doit(|| {
+            ONCE.call_once(|| {
                 imp::mach_timebase_info(&mut TIMEBASE);
             });
             let time = imp::mach_absolute_time();