I want to make an infinity loop with two void functions in c++

Question

I was wondering if there is a way to make an infinity loop the first function will call the second and the second will call the first and so on. Please make a code in C++. Thanks already.

It is possible. The main question is will you be able to have `tail call optimization` on both functions? Otherwise, it will not be infinite. Good luck. — stefaanv, Apr 04 '17 at 13:41
I am interested in why? Also why do you need to two void functions? — CodeCupboard, Apr 04 '17 at 13:55

AlexG · Answer 1 · 2017-04-04T13:50:41.130

3

void foo();
void bar();

void foo(){
    bar();        
    }

void bar(){
    foo();
    }


int main() {
    foo();
    return 1;
    }

Not sure what you're trying to achieve here...? except.. StackOverflow.. ohhh!

edited Apr 04 '17 at 13:50

answered Apr 04 '17 at 13:39

AlexG

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You beat me to it ;-) except that you will need a main entry point? – Shaun Bebbers Apr 04 '17 at 13:40
1

@ShaunBebbers To be honest I'd rather not give any entry point for such a degenerate atrocity, but updated anyway :) – AlexG Apr 04 '17 at 13:43
Does not really work, clang and icc compile this to `int main () {}`. https://godbolt.org/g/7PRTov – Baum mit Augen Apr 04 '17 at 13:45
3

@BaummitAugen right. VS2013 does only compile it in debug, and warns me I'm an idiot in release. :) – AlexG Apr 04 '17 at 13:47
Nobody said the functions had to be empty. Touch a volatile or something. – François Andrieux Apr 04 '17 at 13:50
@AlexG - you need a return value on the `int main()` function so that it grac... oh wait! – Shaun Bebbers Apr 04 '17 at 13:50
2

@ShaunBebbers No you don't, even when the program does terminate. – Baum mit Augen Apr 04 '17 at 13:50
Hm, how to define "infinity"??? According to my definitiion, this solution surely is not infinite, unless one provides an architecture with infinite memory (oh: where to buy such one? I might be interested in...). On the other hand: a simple `for(;;);` won't run infinitely either as at some point far in the future, hardware will certainly fail due to obsolescence... – Aconcagua Apr 04 '17 at 13:56
@BaummitAugen - I know ;-) – Shaun Bebbers Apr 04 '17 at 14:00
Couldn't one also use a `do...while()` or a simples `while()` loop to achieve more or less the same result? – Shaun Bebbers Apr 04 '17 at 14:01
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@Aconcagua Infinite memory isn't required if the compiler does tail-call optimization! – cdhowie Apr 04 '17 at 14:35
You have UB BTW for empty infinite loop. – Jarod42 Apr 04 '17 at 14:47
@cdhowie Good point... – Aconcagua Apr 04 '17 at 14:57

I want to make an infinity loop with two void functions in c++

1 Answers1