Trying to use GNUstep and libdispatch in an ARC based objective-C program

[Mathias Bauer]

Hi,

I've set up a build environment with the lastest trunk versions of 
GNUstep, clang and libobjc2 on Ubuntu 12.04.

In my program (compiled with ARC) I tried to dispatch a block with

>    dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 
> 0), ^ ...

This crashes immediately when the dispatch_get_global_queue call 
returns. The stack shows that the compiler executes a "retain" call on 
the returned object, but libdispatch does not seem to be compiled with 
objc support at all, so I assume that the returned object just is a c 
struct.

I used

./configure --enable-debug-by-default --enable-objc-nonfragile-abi 
--with-layout=gnustep

for the GNUstep make build and

./configure --disable-mixedabi

for building GNUstep base.

For libdispatch I used the configure provided by the repository at

https://github.com/nickhutchinson/libdispatch.git

I assume that the culprit is in the libdispatch build. I manually 
patched the generated config.h file to support OBJC, but this obviously 
isn't enough.

From reading posts from this list I concluded that there are people 
here that used GNUstep with libdispatch and ARC successfully, so perhaps 
someone can give me a hint how I can solve my problem.

Thanks in advance,
Mathias