全局变量的析构函数中ctrl-c上的AV

Question

Consider following snippet:

#include "stdafx.h"
#include <cstdlib>
#include <iostream>
#include <Windows.h>

using namespace std;

class A
{
public:
    ~A()
    {
        cout << "I am about to die" << endl;
    }
};

A a;

int _tmain(int argc, _TCHAR* argv[])
{
    while (true)
    {
        cout << "Waiting for ctrlc" << endl;
        Sleep(1000);
    }
}

When I press ctrl-c I get an AV with following callstack:

0:001> kn
 # Child-SP          RetAddr           Call Site
00 000000c0`dcdbf420 000007fe`9244fab9 MSVCP120D!std::locale::locale+0x2e [f:\dd\vctools\crt\crtw32\stdhpp\xlocale @ 324]
01 000000c0`dcdbf450 000007fe`92454e25 MSVCP120D!std::ios_base::getloc+0x29 [f:\dd\vctools\crt\crtw32\stdhpp\xiosbase @ 424]
*** WARNING: Unable to verify checksum for JustPlayC.exe
02 000000c0`dcdbf490 000007f7`524c33c0 MSVCP120D!std::basic_ios<char,std::char_traits<char> >::widen+0x25 [f:\dd\vctools\crt\crtw32\stdhpp\ios @ 127]
03 000000c0`dcdbf4f0 000007fe`9246570e JustPlayC!std::endl<char,std::char_traits<char> >+0x40 [c:\program files (x86)\microsoft visual studio 12.0\vc\include\ostream @ 999]
04 000000c0`dcdbf520 000007f7`524c2cb1 MSVCP120D!std::basic_ostream<char,std::char_traits<char> >::operator<<+0x2e [f:\dd\vctools\crt\crtw32\stdhpp\ostream @ 201]
05 000000c0`dcdbf550 000007f7`524cefb1 JustPlayC!A::~A+0x41
06 000000c0`dcdbf580 000007fd`edd558c3 JustPlayC!`dynamic atexit destructor for 'a''+0x21
07 000000c0`dcdbf5b0 000007fd`edd551b3 MSVCR120D!doexit+0x133 [f:\dd\vctools\crt\crtw32\startup\crt0dat.c @ 628]
08 000000c0`dcdbf620 000007fd`edd55aeb MSVCR120D!_cexit+0x13 [f:\dd\vctools\crt\crtw32\startup\crt0dat.c @ 449]
09 000000c0`dcdbf650 000007fd`edd559c1 MSVCR120D!__CRTDLL_INIT+0x10b [f:\dd\vctools\crt\crtw32\dllstuff\crtlib.c @ 325]
0a 000000c0`dcdbf6a0 000007fe`d916ecef MSVCR120D!_CRTDLL_INIT+0x31 [f:\dd\vctools\crt\crtw32\dllstuff\crtlib.c @ 215]
0b 000000c0`dcdbf6d0 000007fe`d9180f6c ntdll!LdrpCallInitRoutine+0x3f
0c 000000c0`dcdbf720 000007fe`d9180e0c ntdll!LdrShutdownProcess+0x142
0d 000000c0`dcdbf830 000007fe`d612870f ntdll!RtlExitUserProcess+0xac
0e 000000c0`dcdbf870 000007fe`d61286e7 KERNELBASE!DefaultHandler+0xf
0f 000000c0`dcdbf8a0 000007fe`d8841842 KERNELBASE!CtrlRoutine+0x9b
10 000000c0`dcdbf990 000007fe`d9174f45 KERNEL32!BaseThreadInitThunk+0x1a [d:\win8_gdr\base\win32\client\thread.c @ 65]
11 000000c0`dcdbf9c0 00000000`00000000 ntdll!RtlUserThreadStart+0x1d

Can anyone help me understand what is going on? Looks like MSVCP locale gets uninitalized before global variable destructor which relies on locale? What is the proper way to get around this?

Answer 1

From my understanding of the way the runtime works is that the global variable A is created at initialization time of the runtime, before main() is called. It is therefore tied to the locale of the underlying OS rather than the local of the application in this instance. The locale of the application is therefore disposed before the global is destructed. As someone pointed out, if you want the destructor to use the locale of the application, then the best way is to use a handler for ctrl-c. However, if this object was constructed inside of main, then it becomes a true runtime construction and wouldn't suffer this issue.