auto keyword is not deducing type of string

Question

I've this simple code:

#include <string>
#include <iostream>

using namespace std;

int main() {
    string s1 = "rohit";
    auto len = s1.size();

    cout << len;
}

When I compile this code on Ubuntu 12.04, it shows following error:

test.cc: In function ‘int main()’:
test.cc:8:10: error: ‘len’ does not name a type
     auto len = s1.size();
          ^
test.cc:10:13: error: ‘len’ was not declared in this scope
     cout << len;
             ^

I've got g++ 4.8.1. Is there some changes with the usage of auto keyword in g++ 4.8.1?

Answer 1

The error: ‘len’ does not name a type leads me to believe that you didn't compile in C++11 mode and that it's using the old, C++98 meaning of the keyword auto.