===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/cmd.c,v
retrieving revision 1.123
retrieving revision 1.124
diff -c -r1.123 -r1.124
*** src/usr.bin/tmux/cmd.c	2016/10/05 12:32:13	1.123
--- src/usr.bin/tmux/cmd.c	2016/10/13 10:01:49	1.124
***************
*** 1,4 ****
! /* $OpenBSD: cmd.c,v 1.123 2016/10/05 12:32:13 nicm Exp $ */
  
  /*
   * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
--- 1,4 ----
! /* $OpenBSD: cmd.c,v 1.124 2016/10/13 10:01:49 nicm Exp $ */
  
  /*
   * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
***************
*** 456,467 ****
  			current = &parent->state.tflag;
  		else if (c == 's')
  			current = &parent->state.sflag;
! 	} else {
  		error = cmd_find_current(&tmp, cmdq, targetflags);
  		if (error != 0 && ~targetflags & CMD_FIND_QUIET)
  			return (-1);
  		current = &tmp;
  	}
  
  	switch (flag) {
  	case CMD_NONE:
--- 456,470 ----
  			current = &parent->state.tflag;
  		else if (c == 's')
  			current = &parent->state.sflag;
! 	}
! 	if (current == NULL || !cmd_find_valid_state(current)) {
  		error = cmd_find_current(&tmp, cmdq, targetflags);
  		if (error != 0 && ~targetflags & CMD_FIND_QUIET)
  			return (-1);
  		current = &tmp;
  	}
+ 	if (!cmd_find_empty_state(current) && !cmd_find_valid_state(current))
+ 		fatalx("invalid current state");
  
  	switch (flag) {
  	case CMD_NONE:
***************
*** 557,562 ****
--- 560,572 ----
  	error = cmd_prepare_state_flag('s', s, entry->sflag, cmdq, parent);
  	if (error != 0)
  		return (error);
+ 
+ 	if (!cmd_find_empty_state(&state->tflag) &&
+ 	    !cmd_find_valid_state(&state->tflag))
+ 		fatalx("invalid -t state");
+ 	if (!cmd_find_empty_state(&state->sflag) &&
+ 	    !cmd_find_valid_state(&state->sflag))
+ 		fatalx("invalid -s state");
  
  	return (0);
  }