Re: Building on OSX

[David Chisnall]

On 23 Jan 2009, at 11:56, Wolfgang Lux wrote:

> Giuseppe Luigi Punzi wrote:
>
> > > If you use gnustep-startup, they are compiled to be stand-alone  
> > > (i.e. separate from Cocoa). FYI, GNUstep will compile on 10.5, but  
> > > it won't work, AFAIK.
> > DOH! If don't work, then I don't need this. Obviosly, the idea is  
> > share code between
> > my Windows <-> OSX machines.
>
> It is possible to get up a working GNUstep system on OS X, but doing  
> this is non-trivial. The issue on OS X is that we have two  
> conflicting Objective C runtimes, the GNUstep one and the Apple one.  
> Having both linked with your program almost instantly leads to a  
> crash. Unfortunately, since OS X 10.4 Apple's CoreFoundation library  
> uses Apple's Objective C runtime and a lot of open source projects  
> nowadays make use of Apple specific features on OS X, which  
> (directly or indirectly) use CoreFoundation.

The easiest way of running GNUstep on OS X at the moment is in a VM.   
Since GNUstep and Cocoa implement the same APIs, there isn't much  
interest in making sure GNUstep runs well on OS X - unless you are  
doing any deep hacking with the runtime the code will be the same on  
both.

> Maybe somebody will have a look at making GNUstep work with Apple's  
> Objective C runtime (i.e., an apple-gnu-gnu combo), but until then,  
> you'll have to be brave (and a bit masochist :-) in order to find  
> out all GNUstep dependencies that use CoreFoundation on OS X and  
> either disable them during GNUstep's configuration or recompile them  
> in a way such that they don't use Apple specific features.

Fairly high up my to-do list is implementing the API exposed by  
Apple's runtime on 10.5 on top of the GNU runtime.  This is a really  
nice, clean, API and should make supporting multiple runtimes much  
easier in future.

David