1671   int *nullable;		/* Nullable stack. */  in dfaanalyze()  local
1698   MALLOC(nullable, int, d->depth);  in dfaanalyze()
1699   o_nullable = nullable;  in dfaanalyze()
1723 	*nullable++ = 1;  in dfaanalyze()
1747 	  nullable[-1] = 1;  in dfaanalyze()
1766 	if (nullable[-2])  in dfaanalyze()
1774 	if (nullable[-1])  in dfaanalyze()
1787 	nullable[-2] = nullable[-1] && nullable[-2];  in dfaanalyze()
1788 	--nullable;  in dfaanalyze()
1802 	nullable[-2] = nullable[-1] || nullable[-2];  in dfaanalyze()
1803 	--nullable;  in dfaanalyze()
1812 	*nullable++ = d->tokens[i] == BACKREF;  in dfaanalyze()
1830       fprintf(stderr, nullable[-1] ? " nullable: yes\n" : " nullable: no\n");  in dfaanalyze()