[PATCH 1/3] container_of: apply typeof_member() to container_of()

[Vincent Mailhol]

container_of() uses the construct below:

	((type *)0)->member

to retrieve the type of the structure's member and then ensure that it
matches the type of the given pointer.

This construct being rather difficult to understand, the typeof_member()
macro was created to encapsulate it and give it a descriptive name.

Apply typeof_member() to container_of() to make it easier to read and
understand what this macro does.

Signed-off-by: Vincent Mailhol <mailhol@xxxxxxxxxx>
---
 include/linux/container_of.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/container_of.h b/include/linux/container_of.h
index 1f6ebf27d962..28500a62ab7e 100644
--- a/include/linux/container_of.h
+++ b/include/linux/container_of.h
@@ -18,7 +18,7 @@
  */
 #define container_of(ptr, type, member) ({				\
 	void *__mptr = (void *)(ptr);					\
-	static_assert(__same_type(*(ptr), ((type *)0)->member) ||	\
+	static_assert(__same_type(*(ptr), typeof_member(type, member)) || \
 		      __same_type(*(ptr), void),			\
 		      "pointer type mismatch in container_of()");	\
 	((type *)(__mptr - offsetof(type, member))); })

-- 
2.54.0