Objective-C 2 on GNUstep?

[Kevin Horton]

I'm working through an Objective-C 2 text, and plan to eventually write 
a couple of small apps that I will use on iOS, OS X and GNUstep.  I'll 
do most of the app writing on OS X, but I hope to use a Linux netbook to 
work through this text while travelling.

I've found a bit of general info on what I need to compile and run 
Objective-C code that uses some "Objective-C 2" features, but no 
specific info has leapt to my eye.  Is there any detailed info available 
on what I need to build, and how to build it, to be able to compile and 
run Objective-C 2 code?

Thanks,
--

Kevin Horton
Ottawa, Canada