lambdas: this capture ignores constness (vs std::bind)

I have a little example here below that has two functions (getFoo1...2) that returns a std::function.

• In both cases the getters are const.
• getFoo1 generates the return type by using a lambda with a this capture.
• getFoo2 generates the return type by using std::bind.
• In both cases the real function is non-const.
• The lambda case compiles fine (therefore constness lost...).
• The binder complains about constness of this (as expected, as the member function pointer is non const and requires a non const T to bind on).

I'm concerned with regards to the lambda behaviour (I EXPECTED IT TO NOT COMPILE, AS WITH getFoo2). Any insights would be welcome.

Note: Compiler used GCC 4.8.*.

#include <iostream>
#include <functional>

struct X
{
    void foo(){ std::cout << " non const !!!! foo called" << std::endl;}

    std::function<void()> getFoo1() const
    {
        //Compiles, even though "non const" this required...
        return [this]{foo();};
    }

    std::function<void()> getFoo2() const
    {
        //Fails to compiler due to non const this required
        return std::bind(&X::foo, this);
    }
};

int main() 
{

    X().getFoo1()();
    X().getFoo2()();
    return 0;
}

Kind regards,

Werner