#define _CRTDBG_MAP_ALLOC
#include <iostream>
#include<stdlib.h>
#include<crtdbg.h>
int main()
{
cout<<"test"<<endl;
{
int* pInt = new int(10);
cout<<*pInt<<endl;
}
_CrtDumpMemoryLeaks();
system("pause");
return 0;
}
如果不使用 #define _CRTDBG_MAP_ALLOC 语句，内存泄漏的输出是这样的：
Detected memory leaks!
Dumping objects ->
{45} normal block at 0x00441BA0, 2 bytes long.
Data: <AB> 41 42
可是我使用啦#define _CRTDBG_MAP_ALLOC 语句，内存泄漏的输出是一样的 请问是怎么回事呐..
------解决方案--------------------
_CRTDBG_MAP_ALLOC宏对malloc有效， 对new无效
你可以自行添加
- C/C++ code
#define DEBUG_NEW new(_NORMAL_BLOCK, __FILE__, __LINE__)#define new DEBUG_NEW
------解决方案--------------------
会提示 在哪个文件的哪一行呀
调试运行看output窗口
- C/C++ code
#define _CRTDBG_MAP_ALLOC#include <iostream>#include<stdlib.h> #include<crtdbg.h>using namespace std;#define DEBUG_NEW new(_NORMAL_BLOCK, __FILE__, __LINE__)#define new DEBUG_NEWint main(){ cout<<"test"<<endl; { int* pInt = new int(10); cout<<*pInt<<endl; } //double* pDouble = (double*)malloc(10); _CrtDumpMemoryLeaks(); system("pause"); return 0;}
------解决方案--------------------
这里解释了为什么对new无效以及应该怎么做（如同#1楼#3楼所指出）http://support.microsoft.com/kb/140858
<crtdbg.h>里也有描述：
- C/C++ code
#if defined(_CRTDBG_MAP_ALLOC) && defined(_CRTDBG_MAP_ALLOC_NEW)/* We keep these inlines for back compatibility only; * the operator new defined in the debug libraries already calls _malloc_dbg, * thus enabling the debug heap allocation functionalities. * * These inlines do not add any information, due that __FILE__ is expanded * to "crtdbg.h", which is not very helpful to the user. * * The user will need to define _CRTDBG_MAP_ALLOC_NEW in addition to * _CRTDBG_MAP_ALLOC to enable these inlines. */_Ret_bytecap_(_Size) inline void * __CRTDECL operator new(size_t _Size) { return ::operator new(_Size, _NORMAL_BLOCK, __FILE__, __LINE__); }_Ret_bytecap_(_Size) inline void* __CRTDECL operator new[](size_t _Size) { return ::operator new[](_Size, _NORMAL_BLOCK, __FILE__, __LINE__); }#endif /* _CRTDBG_MAP_ALLOC && _CRTDBG_MAP_ALLOC_NEW */
------解决方案--------------------
补充一下
#define _CRTDBG_MAP_ALLOC
#define _CRTDBG_MAP_ALLOC_NEW
为避免重定义，VC编译选项里须开启 /Ob1（内联），同时把/ZI 改成 /Zi，否则与内联冲突
然后就可以发现泄露总被定位到
Detected memory leaks!
Dumping objects ->
×××\Microsoft Visual Studio 9.0\VC\include\crtdbg.h(1203)
这个信息是 not very helpful to the user.
因此不如不定位
------解决方案--------------------
地址丢了不代表内存就被释放了,哥哥.
指针是指针, 内存是内存.
------解决方案--------------------