我使用的编译器是Visual VC++ 2013。下面这个最简单的程序会导致一些内存泄漏。
为什么?如何修复?
#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>
#include <cstdlib>
#include <iostream>
#include <locale>
using namespace std;
int main()
{
_CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF|_CRTDBG_LEAK_CHECK_DF);
cout.imbue(locale("")); // If this statement is commented, then OK.
}
调试窗口输出如下:
Detected memory leaks!
Dumping objects ->
{387} normal block at 0x004FF8C8, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{379} normal block at 0x004FF678, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{352} normal block at 0x004FE6E8, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{344} normal block at 0x004FE498, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{318} normal block at 0x004FD5C8, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{308} normal block at 0x004F8860, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
Object dump complete.
Detected memory leaks!
Dumping objects ->
{387} normal block at 0x004FF8C8, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{379} normal block at 0x004FF678, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{352} normal block at 0x004FE6E8, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{344} normal block at 0x004FE498, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{318} normal block at 0x004FD5C8, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
{308} normal block at 0x004F8860, 12 bytes long.
Data: <z h - C N > 7A 00 68 00 2D 00 43 00 4E 00 00 00
Object dump complete.
The program '[0x5B44] cpptest.exe' has exited with code 0 (0x0).
cout
析构函数之前或之后它会被调用:允许在第一次使用cout
之前延迟其初始化,并且使用atexit
注册的函数在调用atexit
时运行,在已经序列化初始化的静态持续时间对象的析构函数之前运行(C++11 §3.6.3 ¶3)。由于第一次使用cout
在atexit
之后,因此无法确定在lambda运行时cout
的析构函数是否已经被调用。C++中全局变量的规则非常疯狂。 - Matteo Italiaint main() { _CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF|_CRTDBG_LEAK_CHECK_DF); std::cout.imbue(std::locale(""));}
问题是一样的。 - xmllmx