What is the randomness of the return value of the malloc function?

I found this code snippet in an old and dusty project:

int *p = (int*)malloc(sizeof(p));           // generate random number
free(p);                                    // free up space
int rand = p%3;                             // get random value in between 0-2

Apart from it being bad style and unnecessary as we got srand in the C standard lib, what is the actual randomness of the return value?

While true randomness is not needed in the context it is used, I tested it several times for 99999999 iterations each and for every single test run rand == 0 was less often true than both other cases (rand == 1 and rand == 2).

One example:

• rand == 0: true 27343746 times out of 99999999
• rand == 1: true 36328138 times out of 99999999
• rand == 2: true 36328115 times out of 99999999