Error: Void value not ignored as it ought to be in C programming

Question

I am writing a C program which has two functions. One function is the usual main function and the other is a pointer void function. When I try to compile my program in a Linux

Answer 1

This:

void function_1(int *num1, int *num2)

returns nothing. void is kind of a "nothing" type, in an expression, it means to ignore the result, as a return type, it means nothing is returned. Assigning the (non-existent) return value of a void function doesn't make sense.