Re: [PATCH] NetBSD/i386 port

[Hollis Blanchard]

On Dec 1, 2005, at 7:48 AM, Marco Gerards wrote:
> > Files affected: kern/mm.c, normal/misc.c
> >
> > This is probably more a gcc issue (my is gcc version 3.3.3 (NetBSD nb3
> > 20040520)). As of 2.0, NetBSD/i386 uses non-executable mapping of 
> > stack
> > and thus when nested functions are used it generates call to
> > __enable_execute_stack() (which is actually in libgcc) even if 
> > -nostdlib
> > is used. Since I know no way to disable this behavior (but there 
> > might be
> > some) only workaround known to me is providing dumb 
> > __enable_execute_stack()
> > functions where apropriate.
>
> When is this required?  When using grub-emu or any other userland
> utility?  In that case GRUB is linked to the C library.
>
> In the case it is used for GRUB itself, it is useless.  GRUB executes
> within its own environment.  So in that case we should just make sure
> this doesn't show up.  Perhaps by using different compiler flags.

I think this is a problem Peter Jones was telling me about with Fedora 
as well (non-executable stack conflicting with nested functions).

Peter, do you know anything about that __enable_execute_stack()? 
http://gcc.gnu.org/ml/gcc-patches/2004-07/msg01700.html seems to 
indicate it's only for Solaris, NetBSD, FreeBSD/SPARC64 and OSF, but it 
sounds like we need it on Linux as well?

-Hollis