PREV
ep = PREV(first_invalid);
MEVENT *prev = PREV(eventp);
prev = PREV(prev);
prev = PREV(event, ev_link);
for (mf = LAST(mntfs, qhead); mf != HEAD(mntfs, qhead); mf = PREV(mntfs, mf)) {
for (mf = LAST(mntfs, qhead); mf != HEAD(mntfs, qhead); mf = PREV(mntfs, mf)) {
| PREV
%token <data> QSTR STR PREV BITLAB
| PREV NL {} /* Lines containing only whitespace. */