Heap corruption detected error when attempting to free pointer

Posted by AndyGeek on Stack Overflow See other posts from Stack Overflow or by AndyGeek
Published on 2010-12-24T19:49:31Z Indexed on 2010/12/24 19:54 UTC
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c++

|

memory-management

Hi,

I'm pretty new to C++ and have run into a problem which I have not been able to solve. I'm trying to convert a System::String to a wchar_t pointer that I can keep for longer than the scope of the function. Once I'm finished with it, I want to clean it up properly. Here is my code:

static wchar_t* g_msg;

int TestConvert()
{
    pin_ptr<const wchar_t> wchptr = PtrToStringChars("Test");
    g_msg = (wchar_t*)realloc(g_msg, wcslen(wchptr) + 1);
    wcscpy(g_msg, wchptr);

    free (g_msg); // Will be called from a different method
}

When the free is called, I'm getting "HEAP CORRUPTION DETECTED: after Normal block (#137) at 0x02198F90."

Why would I be getting this error?

Andrew L

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