> Hmm, I am using -current with the new toolchain and lots kde
> apps core dump.  I have rebuilt everything with -O and the
> same problem occurs.  Has anyone else seen this?

Yes.  And the Problem is (surprise, surprise) -- threads.
Clean up everything from the ground up:

# pkg_delete -r ptl
# pkg_delete -r pth

In my case, I also cleaned up low-level color management and
rendering, unlimit (I use zsh(1)-ed root), and rebuilt kde2.
Should be fine thereafter.  Except kdeinit, of course, which
coredumps every time you logoff.  In my case, I forced myself
to play with it for a few days, but came back to fvwm2.  You
just cannot replace that beast...

-Evgeni

PS Oh, all that if you're sitting on i386, of course, --evb