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cmemory-leakscrt

Using _crtBreakAlloc to find memory leaks - identifier "_crtBreakAlloc" is unidentified

I am trying to use _crtBreakAlloc in the Watch window as suggested in this link, but the value line says that 'identifier "_crtBreakAlloc" is unidentified' and it simply does not work.

What am I doing wrong? I'm using Visual Studio by the way.

An example of code:

#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>

#include <malloc.h>


int main()
{
    int *arr = (int*)malloc(10 * sizeof(int)); //breakpoint here
    free(arr);
    return 0;
}

I then write _crtBreakAlloc into the Name field of the Watch window and hit enter when encountering the breakpoint.

Solution

  • _crtBreakAlloc is a macro under VS2015 that is replaced by a call to a function returning a pointer to an int. Tracking a variable in the watch window doesn't seem an option.
    Better insert in your (debug) code something like this: 

    _crtBreakAlloc = 18;