===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/cmd.c,v
retrieving revision 1.123
retrieving revision 1.124
diff -u -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 +1,4 @@
-/* $OpenBSD: cmd.c,v 1.123 2016/10/05 12:32:13 nicm Exp $ */
+/* $OpenBSD: cmd.c,v 1.124 2016/10/13 10:01:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -456,12 +456,15 @@
 			current = &parent->state.tflag;
 		else if (c == 's')
 			current = &parent->state.sflag;
-	} else {
+	}
+	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:
@@ -557,6 +560,13 @@
 	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);
 }