This file was ignored by CVS in my last commit for some reason:

Remove pointless initialization of b_spc field, which now no longer
exists.

sys/vm/swap_pager.c

@@ -1334,7 +1334,6 @@ swap_pager_putpages(object, m, count, sync, rtvals)
 			bp->b_flags = B_ASYNC;
 		}
 		bp->b_iocmd = BIO_WRITE;
-		bp->b_spc = NULL;	/* not used, but NULL-out anyway */
 
 		pmap_qenter((vm_offset_t)bp->b_data, &m[i], n);