Question

Possible Duplicate:
What is a stack overflow error?

look the code below.

#include <iostream>
using namespace std;

void leave(double as){
    cout<<as;
    leave(as);
}


int main(){
    double x=1234.5;
    leave(x);
    cout<<"hellow";
}

When this code executes their is no way to stop. it should print the value x over and over again. But practically, this works for about 20 secs and close automatically. It doesn’t print the line hellow. What is the reason for it? In windows task manager I can realize that the memory used with the application will increase. but I have allocated memory for x within the main function only, so will the function allocate memory for x over and over again. Is this type of situation called a memory leak? if its so what lines should be added to prevent it?

If I change the code as below it shows the word hellow without going through the function over and over again:

 void leave(){
     leave();
  }

  int main(){
      leave();
      cout<<"hellow";
  }

How to explain these situations?

Answer 1

Every call to leave() results in adding a little information to the stack. When you call it recursively, the stack grows until it runs out of space, and the operating system terminates the application. In the second example, presumably the compiler optimized out the function that did nothing.