[uClibc]Shared libraries support on MMU-less ARM

[David McCullough]

Jivin Erik Andersen lays it down ...
> On Mon Jul 08, 2002 at 06:52:58PM -0700, Jason Huang wrote:
> > Hello list members,
> > 
> > I got the news that RidgeRun who completed the shared libraries work
> > (and yet to release to uClibc) ceased its operation last week. I am
> > wondering if the work results will ever be put back into the uClibc
> > base. Or, is there any other way I can get the shared libraries support
> > on MMU-less ARM platform? 
> 
> Hmm.  Hadn't heard that about RidgeRun -- bummer.  In addition

Yeah,  I just found out yesterday while reading the PicoGUI homepage.
Wasn't expecting that one.

> to RidgeRun's work, there is a separate implementation of
> mmu-less shared libraries that was done by SnapGear.

We currently have an implementation for m68k that is available in the
current 2.4 uClinux kernel and the current m68k-elf-tools.

The only doc is the source and you would need the uClinux-dist that
Greg Ungerer (gerg at snapgear.com) releases to see examples of how to setup
the user/lib part of the build (the 3com/Xcopilot target does it).
Check the uClinux-dev list,  a new version went up yesterday and was
announced on the list.

As I said,  it's only m68k based,  but the compiler changes needed
shouldn't be too hard to do for ARM.  In it's simplest explanation yet,
the code that loads the GOT entries just needs a double indirect rather
than a single indirect when the shared library options are in use.

> Thus far,
> neither has submitted any work to me for inclusion in uClibc...

At this point we have only done it for uC-libc,  but it should not be hard
to make uClibc work,  we just haven't had the time/motivation to do it yet.
When we do we will make it available :-)

Cheers,
Davidm

-- 
David McCullough:    Ph: +61 7 3435 2815  http://www.SnapGear.com
davidm at snapgear.com  Fx: +61 7 3891 3630  825 Stanley St., W'gabba QLD 4102, Oz