Template reference argument deduction failure in C++

Why following code doesn't compile in C++14 compiler? If I use

const int i = 10;
int n = fun(i);

The compiler gives an error.

But, If I use

int n = fun(10);

instead of above statements, it's working fine.

Example:

template<typename T>
int fun(const T&&)
{
    cout<<"fun"<<endl;
}

int main()
{
 // int i = 10;         // Not work
    const int i = 10;   // Not work
    int n = fun(i);  
 // int n = fun(10);    // Working fine
}