Mesa (master): util: fix list_is_singular()

[Timothy Arceri]

Module: Mesa
Branch: master
Commit: 0252ba26c545a9752b158470cb66741df0f222ce
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=0252ba26c545a9752b158470cb66741df0f222ce

Author: Timothy Arceri <timothy.arceri at collabora.com>
Date:   Wed Jan 11 15:13:35 2017 +1100

util: fix list_is_singular()

Currently its dependant on the user calling and checking the result
of list_empty() before using the result of list_is_singular().

Cc: "13.0" <mesa-stable at lists.freedesktop.org>
Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>

---

 src/util/list.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/list.h b/src/util/list.h
index e8a99ac..07eb9f3 100644
--- a/src/util/list.h
+++ b/src/util/list.h
@@ -110,7 +110,7 @@ static inline bool list_empty(struct list_head *list)
  */
 static inline bool list_is_singular(const struct list_head *list)
 {
-   return list->next != NULL && list->next->next == list;
+   return list->next != NULL && list->next != list && list->next->next == list;
 }
 
 static inline unsigned list_length(struct list_head *list)