RE: cygwin issues

["Boehm, Hans" <hans_boehm at hp dot com>]

> From: Tom Tromey [mailto:tromey@redhat.com]
> Bryce> As for libgcjdata, this was a hack so that the GC could find
> Bryce> data_start if I recall. Is there anything that still needs
> Bryce> that? Can we stamp it out?
> 
> There's a patch from AG that addresses this for native builds.
> That doesn't help Windows though.  I think we still need it on a
> couple of Linux platforms.
> 
Unless its needed for some embedded platforms, we might consider getting rid
of that in the trunk, or for some later version.  Recent versions of the GC
under Linux should

1) Look for __data_start, and if that fails
2) Look for data_start, and if that fails
3) Look for _end, and walk backwards until they encounter an unwritable
address

I claim at least the 3rd step should work everywhere, though it's suboptimal
in several respects.

I also believe that we're finally in a state in which either the current CVS
glibc or the current linker script arranges to define __data_start
(preferred! - may even be used everywhere now) or data_start on all Linux
platforms.  Unfortunately, that wasn't true for past distributions that are
still out there.

Hans