https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86013
Jonathan Wakely <redi at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID --- Comment #12 from Jonathan Wakely <redi at gcc dot gnu.org> --- That page says "a user-provided non-member function with the same signature defined anywhere in the program, in any source file, replaces the default version. Its declaration does not need to be visible." There's no bug here, I don't think this can be done sensibly.