Is it possible to “constify” a field of `std::pair` without hacks?

Question

In C++, the compiling the following code:

std::pair   x;
static_cast *> (&x);

gi

Answer 1

That's not a cast, but you can do the following:

std::pair  x;
std::pair y( x );

This should work according to §20.2.2/4.