说明，我使用的ide是vs2008
1. 工程设置为debug
内存泄露的检测一般在debug模式下进行
2.在需要检查内存泄露的cpp头部加上
[cpp]
#ifdef _DEBUG
#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>
#define new new(_NORMAL_BLOCK, __FILE__, __LINE__)
#endif
3.代码中插入这么一句话
EnableMemLeakCheck();
[cpp]
inline void EnableMemLeakCheck()
{
_CrtSetDbgFlag(_CrtSetDbgFlag(_CRTDBG_REPORT_FLAG) | _CRTDBG_LEAK_CHECK_DF);
}
4.然后就可以在输出中看泄露情况了
举个例子，例子中我用newEx表示的上述宏定义中的new
[cpp]
int _tmain(int argc, _TCHAR* argv[])
{
EnableMemLeakCheck();
int num = 10;
byte **p = newEx byte *[num];
for (int i = 0; i < num; i ++)
{
Sleep(1);
*p = newEx byte[i];
}
long *pl = newEx long[100];
while(1)
{
Sleep(100);
}
return 0;
}
输出中显示的内容（debug下运行程序，然后点叉叉关闭程序）
memory leaks!
Dumping objects ->
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(101) : {124} normal block at 0x00295CB8, 400 bytes long.
Data: < > CD CD CD CD CD CD CD CD CD CD CD CD CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {122} normal block at 0x00294C30, 9 bytes long.
Data: < > CD CD CD CD CD CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {121} normal block at 0x00294BE8, 8 bytes long.
Data: < > CD CD CD CD CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {120} normal block at 0x00299F88, 7 bytes long.
Data: < > CD CD CD CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {119} normal block at 0x00299F40, 6 bytes long.
Data: < > CD CD CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {118} normal block at 0x00299EF8, 5 bytes long.
Data: < > CD CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {117} normal block at 0x00299EB8, 4 bytes long.
Data: < > CD CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {116} normal block at 0x00299E78, 3 bytes long.
Data: < > CD CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {115} normal block at 0x00299E38, 2 bytes long.
Data: < > CD CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {114} normal block at 0x00299DF8, 1 bytes long.
Data: < > CD
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(92) : {113} normal block at 0x00299DB8, 0 bytes long.
Data: <> 励p
e:\project\test\test_mem_leak\test_mem_leak\test_mem_leak.cpp(88) : {112} normal block at 0x00299D50, 40 bytes long.
Data: <0L) > 30 4C 29 00 CD CD CD CD CD CD CD CD CD CD CD CD
Object dump complete.
有文件名和行号，先申请的后释放。
扩展：
实际上是使用了另外的new，在dbgnew.cpp中，列一个例子说明：
[cpp]
void *__CRTDECL operator new[](
size_t cb,
int nBlockUse,
const char * szFileName,
int nLine
)
_THROW1(_STD bad_alloc)
{
void *res = operator new(cb, nBlockUse, szFileName, nLine );
RTCCALLBACK(_RTC_Allocate_hook, (res, cb, 0));
return res;
}
注意，const char *szFileName可以使用__file__也可以使用自定义的类，经过重载为char*（感谢老马提供代码）
例如：
[cpp]
char new_index_recorder_file_name[1024 * 1024][256];
class new_index_recorder{
public:
new_index_recorder(char* file, int line) : file(file), line(line){
}
operator char*(){
static unsigned int index;
sprintf(new_index_recorder_file_name[index], "%s(%d) : %d ", file, line, index++);
return new_index_recorder_file_name[index];
}
private:
char* file;
int line;
};
当然，也可以用函数来返回char*指针
[cpp]
int g_count = 0;
class OperNew
{
public:
OperNew()
{
g_count ++;
pC = new char[20];
memset(pC, 0, 10);
sprintf(pC, "No.%d", g_count);
}
char* GetChar()
{
return pC;
}
private:
char * pC ;
};
