How does std::numeric_limits<unsigned int>::max() work

Question

I recently learnt that:

The correct way to get the largest possible value of a numeric type on your system is to use std::numeric_limits. In particular, we can use std::numeric_limits<unsigned int>::max() etc.

When reading the documentation of std::numeric_limits, I found that std::numeric_limits is a class template. My question is: How does std::numeric_limits find the type-/system-dependent largest/smallest value? I mean, how is that class template implemented?

In certain cases, I have seen that cppreference has a section labeled "Possible implementation" but, in the case of std::numeric_limits there is no such section.

I know that it will vary across platforms, but I just want to see one possible case to get an idea of how it is working and if is there a way to find the maximum/minimum value for a given type/system manually.

Answer 1

How does std::numeric_limits find the type-/system-dependent largest/smallest value? I mean, how is that class template implemented?

Nothing is "found". std::numeric_limits is simply instantiated differently for different types. Have a look at its instantiation for int, within the GNU implementation of the C++ standard library.

The instantiation values are such that, on the target platform, they are valid.