avoiding multiple free calls on dynamically allocated memory

[sdkumar00]

How can we avoid/detect multiple free calls for a dynamically allocated memory.

void example() {
  int *a;
  a = (int *)malloc(10);
  free(a);
  free(a); //how can we detect/avoid multiple free calls
}

[hype261]

I don't believe there is a way to tell if a piece of memory has already been freed or not. It is up to the programmer to exercise good memory management.

[weaknessforcats]

Set the deleted pointer to 0.

Calling free() with a zero pointer is OK.

However, if you have another pointer containing the same address, then all bets are off unles tyou implement reference checking. Very hard in C but in C++ you can use a Handle class.

The best thing is to run a profiler on your code after you think its working.