From: Paul Kranenburg <pk@cs.few.eur.nl>
   Date: Thu, 13 Jun 1996 02:37:18 +0200 (MET DST)

   I guess I'm going to turn that macro in a no-op for the
   sparc. Maybe this particular trap can actually be handled without
   much fuss in kernel mode, but I'm slowly beginning to dread these
   presumptuous ``__builtin_*''s.

No need to no-op it, just make a special path of execution within
locore for the from-kernel case of "ta 3".  You do nwindows saves and
restores unconditionally.  __builtin_return_address(x) is a very
useful debugging feature in the kernel.

Later,
David S. Miller
dm@sgi.com