On Tue, Nov 11, 2025 at 12:01:19PM +0900, Gustavo A. R. Silva wrote: > -Wflex-array-member-not-at-end was introduced in GCC-14, and we are > getting ready to enable it, globally. > > Use the new TRAILING_OVERLAP() helper to fix the following warning: > > fs/ocfs2/xattr.c:52:41: warning: structure containing a flexible array member > is not at the end of another structure [-Wflex-array-member-not-at-end] > > This helper creates a union between a flexible-array member (FAM) and a > set of MEMBERS that would otherwise follow it. > > This overlays the trailing MEMBER struct ocfs2_extent_rec er; onto the > FAM struct ocfs2_xattr_value_root::xr_list.l_recs[], while keeping the > FAM and the start of MEMBER aligned. > > The static_assert() ensures this alignment remains, and it's > intentionally placed inmediately after the related structure --no > blank line in between. > > Signed-off-by: Gustavo A. R. Silva <[email protected]>
LGTM. Reviewed-by: Heming Zhao <[email protected]> > --- > fs/ocfs2/xattr.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c > index d70a20d29e3e..09069defd7e1 100644 > --- a/fs/ocfs2/xattr.c > +++ b/fs/ocfs2/xattr.c > @@ -49,9 +49,13 @@ > #include "ocfs2_trace.h" > > struct ocfs2_xattr_def_value_root { > - struct ocfs2_xattr_value_root xv; > - struct ocfs2_extent_rec er; > + /* Must be last as it ends in a flexible-array member. */ > + TRAILING_OVERLAP(struct ocfs2_xattr_value_root, xv, xr_list.l_recs, > + struct ocfs2_extent_rec er; > + ); > }; > +static_assert(offsetof(struct ocfs2_xattr_def_value_root, xv.xr_list.l_recs) > == > + offsetof(struct ocfs2_xattr_def_value_root, er)); > > struct ocfs2_xattr_bucket { > /* The inode these xattrs are associated with */ > -- > 2.43.0 > >
