https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114564
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Status|UNCONFIRMED |NEW Keywords| |rejects-valid Known to fail| |4.1.2 Last reconfirmed| |2024-04-02 --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Confirmed. Simple workaround if needed is to place `typename` before `Derived::Base` . GCC is thinking `Derived::Base` is not a type for some reason ...