> On Nov 13, 2025, at 13:38, Joseph Myers <[email protected]> wrote: > > On Thu, 13 Nov 2025, Qing Zhao wrote: > >>> Maybe this suggests that, as in other cases, an anonymous structure or >>> union involving counted_by should actually be required to be valid without >>> reference to the containing struct or union after all - >> >> So, you mean, we should not support the following case: (requested by >> PR122495 and PR122496): >> >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122495 >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122496 >> >> struct fam_in_union { >> int count; >> union { >> char a; >> char fam[] __counted_by(count); >> }; >> }; >> >> Since the “counted_by” field, “count”, that is referenced inside the >> anonymous union is declared >> in the outer containing structure. >> ?? > > Indeed. That would be consistent with how anonymous structs and unions > work in other cases, but I don't know if you have use cases that want this > example to work.
PR122495 and PR122496 were reported by Gustavo. Gustavo and Kees, do you have known cases in the current applications (for example, Linux Kernel) that require this feature? Thanks a lot. Qing > > -- > Joseph S. Myers > [email protected]
