Enabling OS X 10.9 support on 10.8 (Mountain Lion)? My MacBook Pro is running OS X 10.8 (Mountain Lion) and I have been literally advised by an authorised vendor not to install 10.9 due to its bugs.

(I would appreciate not to be given the advise to upgrade to 10.9 or higher, that would be a major disruption for my system running bug-free for many years. That is not what I am asking and is not helpful in my case.)

However,
 I have noticed the following entries in the System Information under Software/Developer:


SDKs:
  OS X:
  10.8: (12F37)
  10.9: (13C64)


Does this mean, some of the 10.9 functionalities are available on my machine that aren't currently enabled?

Is it possible to enable these, so that some 10.9 software can be used that currently refuses to install based on my OSX?



As an example, I wonder if that could help me install a more recent C++?
Just because some of the SDK is there from 10.9 does not mean that you have enough of it to run 10.9 software.  So unfortunately you can either upgrade to 10.9 or sit it out on 10.8.