Re: pax and objc

[Michael Baehr]

On Wed, 23 Jun 2004 17:33:08 -0400, Armando Di Cianno
<adicianno@coresense.com> wrote:
> 
> Hello all, I have a quick question about something I'm kind of in the
> dark about.
> 
> Back story: I'm trying to revitalize GNUstep on Gentoo.  Worked on
> ebuilds/structure for a week or two, submitted something like 16
> yesterday.   Getting good feedback.
> 
> One piece of feedback was that Objective-C doesn't play well with pax.
>    I'm not exactly sure what pax is.  So, if anyone knows:
> - What is the nature of the problem between pax and Objective-C?  (I'm
> assuming it's going to have something to do with the library or the
> runtime, and whatever protection PAX is supposed to offer for
> stack/heap breakage.)
> - The problem is between Objective-C support itself and PAX, yes?
> gnustep-base offers support for libffi which doesn't use mprotect like
> ffcall, which I understand to be a problem. (I'm uploading the newest
> libffi that will work with gnustep-base to bugs.gentoo right now as
> well). I wasn't sure if some were mixing "GNUstep" and "objc" in this
> context.
> 
> Any information on this issue would be greatly appreciated.  I'd
> really like GNUstep on Gentoo to be as solid as it can feasibly be.
> 
> __Armando Di Cianno
> 

I'm glad somebody is working on Gentoo ebuilds; I have had to turn
many of my Gentoo-using friends away from trying GNUstep (sans manual
compilation) due to the outdated state of Gentoo in portage.  So thank
you very much for your work!

As for PaX, it is obviously some sort of stack protection thingamabob.
 That's about the extent of my knowledge about it; is this something
most Gentoo users will have installed/ be building against, or is this
more of a rare case?  Also, I know OpenBSD uses something similar
system-wide, so I'm wondering whether any of the efforts that have
been made to get GNUstep usable on OBSD can be applied in this
situation.

Once again, many thanks :)

-- Mike