>> No need to no-op it, just make a special path of execution within
>> locore for the from-kernel case of "ta 3".
> I know.  But I just wish that these goodies were implemented in, say,
> libgcc whenever possible.

But __builtin_return_address _can't_ be implemented in libgcc.  libgcc
doesn't - can't - know how many windows the machine has; it _has_ to
push this one off to the kernel.  And indeed, it asks the kernel for as
little as possible - just a window-flush; the rest _is_ done by gcc.

					der Mouse

			    mouse@collatz.mcrcim.mcgill.edu