Hi,

In my testing on several targets, I noticed that GDB isn't
building on x86 OpenBSD 4.3, due to the fact that struct
switchframe got its sf_ppl member removed, and GDB is trying
to access it.

I can't claim I know a think about this, but,

The patch that seems to have removed it, shows that is was always
0 just before removal:

 http://archive.netbsd.se/?ml=openbsd-tech&a=2007-09&m=5239543

And I can see it being set to != 0 in that files' history at:
 http://opengrok.creo.hu/openbsd/history/src/sys/arch/i386/i386/vm_machdep.c

So, I guess that the attached is the best to do, and I didn't
notice any breakage.  Of course, I don't even know what
triggers this code path.  :-)

Mark, perhaps you have a better fix in your local trees?

OK?

-- 
Pedro Alves