[Mesa-dev] [PATCH 2/5] util/list: fix member access within null pointer

[Bartosz Tomczyk]

---
 configure.ac    | 3 +++
 src/util/list.h | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/configure.ac b/configure.ac
index a6ceee95a3..87f635c1a3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -415,6 +415,9 @@ AC_C_BIGENDIAN(
    little_endian=no
 )
 
+dnl Chek for typeof support 
+AC_C_TYPEOF()
+
 dnl Check for POWER8 Architecture
 PWR8_CFLAGS="-mpower8-vector"
 have_pwr8_intrinsics=no
diff --git a/src/util/list.h b/src/util/list.h
index 07eb9f3e6a..eaaac43fec 100644
--- a/src/util/list.h
+++ b/src/util/list.h
@@ -171,10 +171,19 @@ static inline void list_validate(struct list_head *list)
  * 'sample' MUST be initialized, or else the result is undefined!
  */
 #ifndef container_of
+#if HAVE_TYPEOF
+#define container_of_typed(ptr, type, member) ({			\
+	const __typeof__( ((type *)0)->member ) *__mptr = (ptr);	\
+	(type *)( (char *)__mptr - offsetof(type,member) );})
+
+#define container_of(ptr, sample, member) \
+	container_of_typed(ptr, __typeof__(*sample), member)
+#else
 #define container_of(ptr, sample, member)				\
     (void *)((char *)(ptr)						\
 	     - ((char *)&(sample)->member - (char *)(sample)))
 #endif
+#endif
 
 #define list_first_entry(ptr, type, member) \
         LIST_ENTRY(type, (ptr)->next, member)
-- 
2.11.1