It turns out the cling issue also means things like hist2workspace don’t work. I think it would be useful to have a warning about using ROOT with GCC 11 until this is fixed.
We discussed the issue with @Axel , our intention is to fix the problems with gcc 11 asap.
(in the meanwhile, the promised updated to the GetResultPtr docs: [DF][NFC][skip-ci] Clarify semantics of ActionHelper::GetResultPtr by eguiraud · Pull Request #8241 · root-project/root · GitHub)
@Axel just merged a fix for the gcc11 issue in master (future v6.26) and in the 6.24 patches branch (future 6.24.02, coming soon).