Re: signal SIGSEGV, Segmentation fault

[Josh Freeman]

Hi Andreas,

On May 3, 2018, at 2:45 PM, Andreas Höschler wrote:

> Segmentation fault
> ...
> while accessing one of its instance variables, actually in the
>
>       NSLog(@"routeVisible: %d", _routeVisible);
>
> line. When I comment this line out I get the same error in the next  
> line while accessing _routePath and so on. I am clueless how to fix  
> this. The code works on MacOSX and also with on an ancient GNUstep/ 
> Debian/Kubuntu setup. Any idea what might cause this trouble on  
> Ubuntu 16.04 with the latest GNUstep or how to further track this  
> down?


   Currently, libobjc2's non-fragile ABI can cause segfaults on  
Debian-based distros (& perhaps other Linux distros) when directly  
accessing some class' instance variables.

   There's a few workarounds for Ubuntu:

* The Ubuntu install script on the wiki has a workaround (it checks  
out an old version of GNUstep-make that builds using the fragile ABI):
http://wiki.gnustep.org/index.php/GNUstep_under_Ubuntu_Linux

* If you need the non-fragile ABI, there's a script + objc2-patch  
attached to this list message:
http://lists.gnu.org/archive/html/discuss-gnustep/2017-12/msg00129.html

* David is working on a new ABI, and you can try his experimental  
builds:
http://lists.gnu.org/archive/html/gnustep-dev/2018-04/msg00051.html

Cheers,

Josh