https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101761
--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> --- http://eel.is/c++draft/atomics#ref.generic.general-3.sentence-2 "While any atomic_ref instances exist that reference the *ptr object, all accesses to that object shall exclusively occur through those atomic_ref instances."