In my Windows 10 system running Ruby 2.3.3, irb told me:
So, obviously, your Windows implementation is not using flonums. The most likely reason is that either you are not using YARV (e.g. using JRuby or Rubinius), or you are using YARV, but a 32 bit version.
Note: Object IDs are a private internal implementation detail of the particular Ruby implementation. The version of Ruby you are using is completely irrelevant. What is relevant is which implementation you are using, which version, which commandline options, how you compiled it, what your environment is and so on. It has nothing to do with the language.
Note also: you should never ever rely on the specific value of Object IDs. Object IDs guarantee two things, and only these two things:
Here are some things that are not guaranteed:
false, as you have just discovered), or that it is always related to the object's value in some way (due to the specific way that YARV optimizes
Integers, the Object ID for small integers will always be 2n+1, but that is only true for small integers (where the definition of "small" depends on whether you run a 64 bit or 32 bit version of YARV) and it is only an implementation detail that may change at any moment without notice).