我今天读微软的DLL的官方文档的时候，看到了这样一句话：

"When handling DLL_PROCESS_DETACH, a DLL should free resources such as heap memory only if the DLL is being unloaded dynamically (the lpvReserved parameter is NULL). "

特别强调：only if！！！

该页面同时还有这样一句话：
＂If your DLL is linked with the C run-time library (CRT), the entry point provided by the CRT calls the constructors and destructors for global and static C++ objects. Therefore, these restrictions for DllMain also apply to constructors and destructors and any code that is called from them.＂

举个例子解释一下：假如你有一个ｕｎｉｑｕｅ＿ｐｔｒ是一个ｇｌｏｂａｌ ｖａｒｉａｂｌｅ．那么，你需要在Dllmain里面视情况把这个ｕｎｉｑｕｅ＿ｐｔｒ给ｒｅｌｅａｓｅ掉，以防止它的析构函数被调用。不然在某些情况下会ｃｒａｓｈ．
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修改:snnn FROM 112.85.242.*
FROM 115.231.225.*

> 稍微好一点的处理，是退进程时，先把所有的线程都停掉（包括码农自己开的线程，和OS API内部开的线程），只剩下主线程。

我说的不是线程的问题。是DLL的退出顺序的问题。
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FROM 112.85.242.*