> In order to combat the problems I've been having with "Profiling timer
> expired" killing off some jobs, I re-supped and figured I'd make myself a
> new kernel, but SYS_sigreturn isn't defined in sys/syscall.h anymore, and
> thus arch/mips/mips/locore.S won't compile anymore.  What gives? 

You got outdated source code.  Most recent locore.S should have $NetBSD$ ID;

/*      $NetBSD: locore.S,v 1.57 1998/10/02 18:44:32 drochner Exp $     */

In that version, SYS_sigreturn was renamed with SYS___sigreturn14.

Tohru Nishimura
Nara Institute of Science and Technology