CAN A POINTER BE FREED MORE THAN ONCE IN C? WHAT HAPPENS IF DO SO? OR CAN A POINTER BE FREED TWICE IN C?

1st scenario: After freeing a pointer in a C program, freed memory might be reallocated by some other or same program luckily. In this scenario, freeing the same pointer twice won’t cause any issue.

2nd scenario: We can free a pointer. Then, we can allocate memory for same pointer variable. Then, we can use it and free it again. This is also not an issue.

3rd scenario: If we free the same pointer second time without reallocating memory to that pointer, then what happens? As per ANSI/ISO C standard, this is undefined behaviour. This undefined behaviour may cause anything to the program that we do not expect to happen.