问题描述
我在使用Visual Studio 2008。
I'm using Visual Studio 2008.
我知道std :: vector已经使用at（）函数进行了边界检查，并且有未定义的行为，如果你尝试使用运算符[]不正确（超出范围）访问某些内容。
I'm aware that std::vector has bounds checking with the at() function and has undefined behaviour if you try to access something using the operator [] incorrectly (out of range).
我很好奇，如果可以使用bounds检查来编译我的程序。这样，运算符[]将使用at（）函数，并且每当某个值超出范围时，都会抛出一个std :: out_of_range。
I'm curious if it's possible to compile my program with the bounds checking. This way the operator[] would use the at() function and throw a std::out_of_range whenever something is out of bounds.
检查运算符[]，所以性能不会降低。
The release mode would be compiled without bounds checking for operator[], so the performance doesn't degrade.
我想到了这个，因为我正在迁移一个应用程序使用Borland C ++写的Visual Studio和在一小部分代码中我有这个（i = 0，j = 1）：
I came into thinking about this because I'm migrating an app that was written using Borland C++ to Visual Studio and in a small part of the code I have this (with i=0, j=1):
v[i][j]; //v is a std::vector<std::vector<int> >
向量'v'的大小为[0] [1]向量只有一个元素）。这是未定义的行为，我知道，但Borland在这里返回0，VS是崩溃。我喜欢崩溃比返回0，所以如果我可以通过std :: out_of_range异常抛出更多的崩溃，迁移将完成更快（所以它会暴露更多的错误，Borland隐藏）。
The size of the vector 'v' is [0][1] (so element 0 of the vector has only one element). This is undefined behaviour, I know, but Borland is returning 0 here, VS is crashing. I like the crash better than returning 0, so if I can get more 'crashes' by the std::out_of_range exception being thrown, the migration would be completed faster (so it would expose more bugs that Borland was hiding).
推荐答案
Visual Studio 2005和2008已经对 operator [] 默认情况下，在 调试和发布版本。
Visual Studio 2005 and 2008 already do bounds-checking on operator[] by default, in both debug and release builds.
控制此行为的宏是。
The macro to control this behavior is _SECURE_SCL. Set it to 0 to disable bounds-checking.
它们在VS2010中的当前计划是在发布版本中默认禁用边界检查，但在调试中保持开启。 （宏也被重命名为 _ITERATOR_DEBUG_LEVEL 。我不知道是否有任何正式文档可用，但它已经提到和）
Their current plan in VS2010 is to disable bounds-checking by default in release builds, but keep it on in debug. (The macro is also getting renamed to _ITERATOR_DEBUG_LEVEL. I don't know if there's any formal documentation available on it yet, but it has been mentioned here and here)
这篇关于如何使std :: vector的运算符[]编译做边界检查DEBUG但不是在RELEASE的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！