In the absence of synchronization, if one thread writes to a variable and another thread reads that same variable, the reading thread could see stale, or out-of-date, data.

没有同步时，如果一个线程读取另外一个线程正在写的变量，读的线程将看到过时的数据。

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In the absence of synchronization, if one thread writes to a variable and another thread reads that same variable, the reading thread could see stale, or out-of-date, data.

没有同步时，如果一个线程读取另外一个线程正在写的变量，读的线程将看到过时的数据。

youdao