Data race condition

The value of the shared data will be determined by the interleaving of thread execution. Thread shared data is accessed without holding an appropriate lock, possibly causing a race condition
/src/mongo/util/clock_source.cpp:66: MISSING_LOCK 115026 Accessing "alarmInfo->cv" without holding lock "mongo::ClockSource::waitForConditionUntil(mongo::stdx::condition_variable &, mongo::BasicLockableAdapter, mongo::Date_t, mongo::Waitable *)::AlarmInfo.mutex". Elsewhere, "_ZZN5mongo11ClockSource21waitForConditionUntilERNS_4stdx18condition_variableENS_20BasicLockableAdapterENS_6Date_tEPNS_8WaitableEE9AlarmInfo.cv" is accessed with "mongo::ClockSource::waitForConditionUntil(mongo::stdx::condition_variable &, mongo::BasicLockableAdapter, mongo::Date_t, mongo::Waitable *)::AlarmInfo.mutex" held 1 out of 2 times (1 of these accesses strongly imply that it is necessary).