buildworld failing

Is anybody else seeing this?  If not, any hint on what's wrong?
I've re-cvsup'd a couple of times with no effect.
I last built -current on 5/7 with no trouble.

cc -O -pipe -march=pentiumpro -DLIBC_SCCS -I/usr/src/lib/libkvm  -c /usr/src/lib/libkvm/kvm_proc.c -o kvm_proc.o
/usr/src/lib/libkvm/kvm_proc.c: In function `kvm_proclist':
/usr/src/lib/libkvm/kvm_proc.c:103: storage size of `procsig' isn't known
/usr/src/lib/libkvm/kvm_proc.c:195: structure has no member named `p_procsig'
/usr/src/lib/libkvm/kvm_proc.c:196: structure has no member named `p_procsig'
/usr/src/lib/libkvm/kvm_proc.c:198: structure has no member named `p_procsig'
*** Error code 1

Apparently sigset_t is not defined.
 
Thanks,
Barney