Getting Objective-C 2.0 working

[Laurent Michel]

Dear All,

I develop on MaOS and would love to port my code to Linux. Essentially, I use 
Objective-C 2.0 with clang as a compiler.
I created an Ubuntu 12.04 VM under VMWare and installed GNUStep through that 
channel. I compiled a silly hello world and that worked fine.
My problems started when I tried to compile my own code which makes *heavy* use 
of Objective-C blocks. I always end-up seeing this message:

clang -I/usr/GNUstep/System/Library/Headers  -fblocks -fobjc-nonfragile-abi -c 
CPFactory.m 
In file included from CPFactory.m:27:
In file included from ./CPFactory.h:27:
In file included from 
/usr/GNUstep/System/Library/Headers/Foundation/Foundation.h:30:
/usr/GNUstep/System/Library/Headers/GNUstepBase/GSVersionMacros.h:287:14: fatal 
error: 'objc/blocks_runtime.h' file not found


namely, it cannot find objc/blocks_runtime.h

I started googling around and I found lots of conflicting information on the 
topic as well as reference to Etoile, and ObjectiveC2 (a framework) but it 
seems largely incompatible with GNUStep. I'll looking for some directions to 
get going with a simple code that uses blocks. For instance, a silly test like:

#import <Foundation/NSObject.h>

int foo(int (^b)(int)) {
   return b(5);
}

int main() {

   int y = 10;
   int z = foo(^(int x) {
         return y + x; 
      });
   NSLog(@"result is %d\n",z);
}


Should compile and run when linked against the Foundation framework. 

Any pointer is greatly appreciated.

--
  Laurent