https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116016
--- Comment #29 from qinzhao at gcc dot gnu.org --- (In reply to Jakub Jelinek from comment #28) > It would need to be a FE keyword where __builtin_get_counted_by would return > some pointer, either e.g. (void *)0 if it doesn't have a count, or a pointer > to the count (with type of the pointer dependent on what type the count has). So, a RID_BUILTIN (i.e, FE keyword) like the following: (void *) __builtin_get_counted_by (ptr) Then the user source code becomes the following: If (__builtin_get_counted_by (P->FAM)) *__builtin_get_counted_by (P->FAM) = COUNT; > > Speaking of counted_by, I see support for it in c-family/ and c/, but not in > cp/ at all, what is the attribute supposed to do in C++? The initial plan is to support it in both C and C++ (since C++ can use flexible array member too through GCC extension), but I didn't implement it in C++ in the initial patch. > If it isn't supported, it should be documented that it doesn't apply to C++ > and should be rejected in C++. If it is to be supported, the support > (including support for templates) needs to be there before GCC 15. I will try to support it in C++ too in GCC15. If not, I will update the documentation to indicate this limitation.
