Value stored when istream read fails

Question

Sample code:

#include 

int main()
{
    int x = 5;
    std::cin >> x;
    std::cout << x << \'\\n\';
}

On on

Answer 1

Yes, this is the correct behaviour since C++11.

• istream behavior change in C++ upon failure

The difference in what you're seeing is that a zero is written "when extraction fails", but extraction is not even attempted if EOF is already set on the stream… so nothing happens.