For example:
class NSNotificationCenter
method deaultCenter
xcode 8.0
OS 10.12
availability macOS (10.12 and later)
BUT
xcode 5.1.1
OS 10.8
availability OS X v10.0 and later
Why? Can I use "deaultCenter" in OS 10.8? And how can I know that some methods have the real "macOS (10.12 and later)" (crash in early OS version) availability?
The current online copy of the defaultCenter
documentation correctly says 10.0+. If Xcode 8 is not agreeing then it's a documentation bug. You can file a report at bugreport.apple.com