diff --git a/options-table.c b/options-table.c
index 054b2700..ab61ef79 100644
--- a/options-table.c
+++ b/options-table.c
@@ -891,6 +891,8 @@ options_table_populate_tree(enum options_table_scope scope, struct options *oo)
 	const struct options_table_entry	*oe;
 
 	for (oe = options_table; oe->name != NULL; oe++) {
+		if (oe->scope == OPTIONS_TABLE_NONE)
+			fatalx("no scope for %s", oe->name);
 		if (oe->scope != scope)
 			continue;
 		switch (oe->type) {
diff --git a/tmux.h b/tmux.h
index 6ed3035c..ed2893b6 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1396,6 +1396,7 @@ enum options_table_type {
 	OPTIONS_TABLE_STYLE
 };
 enum options_table_scope {
+	OPTIONS_TABLE_NONE,
 	OPTIONS_TABLE_SERVER,
 	OPTIONS_TABLE_SESSION,
 	OPTIONS_TABLE_WINDOW,