From patchwork Thu Dec 13 22:04:12 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [2/8] lib/ext2fs/rbtree.h: Fix container_of() undefined behavior Date: Thu, 13 Dec 2012 12:04:12 -0000 From: Sami Liedes X-Patchwork-Id: 206263 Message-Id: <20121213220412.GJ9713@sli.dy.fi> To: linux-ext4@vger.kernel.org The code before the macro definition #undefs and redefines offsetof(). Unfortunately the new definition actually causes undefined behavior. The code checks for __compiler_offsetof() before redefining. However I'm not sure where it is supposed to be defined. Just enclose the redefinition in #ifndef __GNUC__ for now. Caught using clang -fsanitize=undefined. Signed-off-by: Sami Liedes --- lib/ext2fs/rbtree.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/lib/ext2fs/rbtree.h b/lib/ext2fs/rbtree.h index 16defb5..088c352 100644 --- a/lib/ext2fs/rbtree.h +++ b/lib/ext2fs/rbtree.h @@ -96,12 +96,14 @@ static inline struct page * rb_insert_page_cache(struct inode * inode, #include +#ifndef __GNUC__ #undef offsetof #ifdef __compiler_offsetof #define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER) #else #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) #endif +#endif #define container_of(ptr, type, member) ({ \ const __typeof__( ((type *)0)->member ) *__mptr = (ptr); \