Why do you specify the size when using malloc in C?

Question

Take the following code :

int *p = malloc(2 * sizeof *p);

p[0] = 10;  //Using the two spaces I
p[1] = 20;  //allocated with malloc before.

p[2] = 30;  //U         


        

Answer 1

C kindly let you shoot yourself in the head. You have just used random memory on the heap. With unforeseeable consequences.

Disclaimer: My last real C programing was done some 15 years ago.