Comment by chowells

I have a small program which uses an undefined behavior. How would you rewrite this so as to not do so, but maintain all existing defined behaviors?

    #include <stdio.h>

    int main() {
        int a, b, c;
        printf("Please enter two numbers: ");
        scanf("%d %d", &a, &b);
        c = a + b;
        printf("The sum of the numbers you entered is %d\n", c);
        return 0;
    }

This is the problem. There is no non-trivial C code that doesn't use some undefined behavior somewhere. And it works just fine, right now. But who says it will on the next version of the compiler?