在程序的最后一行省略释放内存是完全可以接受的，因为释放它不会对任何事情产生影响，因为程序再也不需要内存了。

看来你对“内存泄漏”的定义是“我自己不清理的内存”。所有现代操作系统都会在程序退出时释放它。然而，由于这是一个c++问题，您可以简单地将所讨论的内存包装在适当的std::auto_ptr中，当它超出作用域时将调用delete。

在这类问题中，语境就是一切。就我个人而言，我不能忍受漏洞，在我的代码中，如果它们突然出现，我就会竭尽全力去修复它们，但修复漏洞并不总是值得的，当人们按小时支付我的报酬时，我有时会告诉他们，我的费用不值得我修复他们代码中的漏洞。让我给你们举个例子:

I was triaging a project, doing some perf work and fixing a lot of bugs. There was a leak during the applications initialization that I tracked down, and fully understood. Fixing it properly would have required a day or so refactoring a piece of otherwise functional code. I could have done something hacky (like stuffing the value into a global and grabbing it some point I know it was no longer in use to free), but that would have just caused more confusion to the next guy who had to touch the code.

就我个人而言，我一开始就不会以这种方式编写代码，但我们大多数人并不总是在设计良好的原始代码库上工作，有时你必须务实地看待这些事情。修复150字节泄漏所花费的时间可以用来改进算法，从而减少兆字节的内存。

最终，我决定为一个使用大约1g内存并运行在专用机器上的应用程序泄露150个字节不值得修复，所以我写了一条评论说它被泄露了，为了修复它需要改变什么，以及为什么当时不值得。

如果分配内存并一直使用到程序的最后一行，这就不是泄漏。如果您分配内存并忘记它，即使内存数量没有增长，这也是一个问题。已分配但未使用的内存可能导致其他程序运行速度变慢或根本不运行。

I'm going to give the unpopular but practical answer that it's always wrong to free memory unless doing so will reduce the memory usage of your program. For instance a program that makes a single allocation or series of allocations to load the dataset it will use for its entire lifetime has no need to free anything. In the more common case of a large program with very dynamic memory requirements (think of a web browser), you should obviously free memory you're no longer using as soon as you can (for instance closing a tab/document/etc.), but there's no reason to free anything when the user selects clicks "exit", and doing so is actually harmful to the user experience.

为什么?释放内存需要接触内存。即使您的系统的malloc实现碰巧没有在分配的内存块附近存储元数据，您也可能会遍历递归结构，只是为了找到所有需要释放的指针。

Now, suppose your program has worked with a large volume of data, but hasn't touched most of it for a while (again, web browser is a great example). If the user is running a lot of apps, a good portion of that data has likely been swapped to disk. If you just exit(0) or return from main, it exits instantly. Great user experience. If you go to the trouble of trying to free everything, you may spend 5 seconds or more swapping all the data back in, only to throw it away immediately after that. Waste of user's time. Waste of laptop's battery life. Waste of wear on the hard disk.

这不仅仅是理论上的。每当我发现自己加载了太多的应用程序，磁盘开始抖动时，我甚至不会考虑点击“退出”。我以最快的速度到达一个终端，输入killall -9…因为我知道"退出"只会让情况更糟。

即使您确定“已知的”内存泄漏不会造成严重破坏，也不要这样做。在最好的情况下，它会为你在不同的时间和地点犯下类似的、可能更严重的错误铺平道路。

对我来说，问这个问题就像问“我可以在凌晨3点没有人的时候闯红灯吗?”当然，在那个时候它可能不会造成任何麻烦，但它将为你在高峰时间做同样的事情提供一个杠杆!