Operator delete causing heap corruption while operator new working fine

Question

I have got operator new working but as soon as I call delete, it crashes at the free (ptr) line. Can any one tell what I am doing wrong when overloading operator new and delete in this Base class? Hint: I am not asking about design issues.

class Base {
private: 
    int i;

public:  
    Base () : i (10) {
    }

    static void * operator new (size_t size) {  
       if (size = 0) size = 1;  // please read this line carefully! size = 0!
       return malloc (size);  
    }

    static void operator delete (void *ptr, size_t size) {
       if (ptr == NULL) return;
       free (ptr);
    }
};

Answer 1

This works for me:

#include <cstdlib>
using namespace std;
class Base {
public:
    void * operator new(size_t size) {
       if (size == 0) size = 1;
       return malloc (size);
    }

    void operator delete (void *ptr, size_t size) {
       if (ptr == NULL) return;
       free (ptr);
    }
};

int main()
{
    Base* b = new Base;
    delete b;
    return 0;
}

---

hank@tardis:/tmp$ g++ -o test test.cpp 
hank@tardis:/tmp$ ./test 
hank@tardis:/tmp$ valgrind ./test 
==7229== HEAP SUMMARY:
==7229==     in use at exit: 0 bytes in 0 blocks
==7229==   total heap usage: 1 allocs, 1 frees, 1 bytes allocated
==7229== 
==7229== All heap blocks were freed -- no leaks are possible
==7229== 
==7229== For counts of detected and suppressed errors, rerun with: -v
==7229== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 4 from 4)