string::c_str query

Question

Where does the pointer returned by calling string::c_str() point to ? In the following code snippet, I thought I will give get a segmentation fault but it gives me the corre

Answer 1

What would you expect this to print out?

#include 
#include 

int main()
{
  int* test = new int[20];
  test[15] = 5;
  std::cout << test[15] << "\n";
  delete[] test;
  std::cout << test[15] << "\n";
  return 0;
}

In release mode on VS 2010, I get this result:

5
5

Deallocated memory doesn't necessarily throw an exception when you try to access it. The value doesn't necessarily get re-written, either. (Interestingly enough, if I change the compile to debug mode, the compiler overwrites the value with -572662307).

What happens when you try to access it is undefined by the standard. That means the compiler can do whatever it feels like doing, or choose to do nothing. (Or crash your program, or blow up the universe...)